The roentgenologic diagnosis of chronic bronchitis: a reassessment with emphasis on parahilar bronchi seen end-on.

In an attempt to reassess the accuracy of the roentgenologic diagnosis of chronic bronchitis, we have studied the chest radiographs of approximately 300 men comprising roughly equal numbers of normal subjects and patients with chronic obstructive pulmonary disease (COPD). Emphasis has been placed on the thickness of bronchial walls visualized end-on in the parahilar zones, identified in roughly 80% of both groups. Step-wise discriminant analysis of six variables showed that the median estimate of bronchial wall thickness was of some value in discrimination.


Cerebral angiotomography.

This study was undertaken with two main objectives: (a) to ascertain in the practicability of two simple types of apparatus and (b) to evaluate the clinical situations in which the procedure was most likely to be helpful. Aneurysms, arteriovenous malformations, vascular diseases, tumors, including pituitary tumors, and head injuries were studied. The technique was found to be most useful in aneurysms, arteriovenous malformations and pituitary tumors.


Traumatic lung and paramediastinal pneumatoceles.

Traumatic pulmonary and paramediastinal pneumatoceles are definite, acutely formed, primary structural manifestations incident to nonpenetrating chest trauma. They are not secondary lesions, i.e., cavities or pneumatoceles resulting from the resolution of a pulmonary hematoma. Awareness of this fact will explain the not uncommon finding of a cavitary lesion, often containing an air-fluid level, on initial emergency room radiographs of patients who have sustained closed chest trauma. This will avoid unnecessary and unpleasant diagnostic procedures, including thoracotomy, for traumatic pneumatoceles are self-limiting, benign abnormalities which usually require no therapy other than observation.


Interhemispheric infarction. Neuroradiological and clinical manifestations.

Evidence of infarction along the interhemispheric fissure was found in 3 clinically dissimilar patients. The neuroradiographic features appear to be sufficiently diagnostic when the appropriate examinations are utilized.


Spinal subdural hematoma.

The authors report a case of subacute spinal subdural hematoma in a patient with ankylosing spondylitis. Only 18 such cases have been reported in the nonradiological literature. Early diagnosis is imperative in order to minimize neurological sequelae.


Duplication of the straight sinus. An angiographic study.

Duplication of the straight sinus is often noted in the venous phase of carotid angiograms. Since this vascular anomaly is rarely described in the literature, the authors present its incidence in a series of 700 cases, and consider its embryological origins and clinical significance.


Contiguous internal carotid arteries in empty sella syndrome.

The cavernous portions of the right and left internal carotid arteries were seen to be nearly contiguous in a patient with empty sella syndrome. On the basis of previous reports, in which specific measurements of the cavernous portions of the internal carotid arteries are given, the authors believe that this case is unique. Carotid angiography may be used to diagnose this syndrome in the presence of a large sella turcica.


Skeletal uptake of 99mTc-diphosphonate in relation to local bone blood flow.

The right/left ratios of tibial uptake of 99mTc-diphosphonate (EHDP) and relative blood flow (based on microsphere distribution) were determined in control rats and rats with a ligated right femoral artery or a healing right tibial fracture. Correlation between 99mTc-EHDP uptake and relative blood flow was highly significant (r=0.917; P less than 0.0001) for relative flow ratios less than 1.7. When the ratio was greater than 1.7, there was little further increase in 99mTc-EHDP uptake. Ligation of the femoral artery in rats with healing fractures resulted in a more marked reduction of blood flow than of 99mTc-EHDP uptake. These results suggest that regional bone blood flow is a major determinant of 99mTc-EHDP uptake, though changes in regional tracer extraction efficiency are also important.


Efficacy of emergency radionuclide perfusion lung studies.

Over a one-year period, 206 patients with suspected pulmonary embolism received gamma camera perfusion lung images on an emergency 24 hr. basis. Clinical diagnosis listed pulmonary embolism in 37 of 39 patients whose images showed a high probability of it, in 28 of 69 whose images were abnormal but rated uncertain probability, and 5 of 98 with normal images. Retrospective clinical evaluation indicated 89 of the emergency images to be considered important, 95 contributory, and 22 not helpful in clinical management. As a result of the images, 80 patients were placed on heparin therapy of 198 considered for it, and 22 of 29 patients referred for hospital admission were placed on an outpatient basis. Delay in obtaining lung images creates the possibility of diagnostic uncertainty in interpreting the image.


Gallium-67 myocardial imaging for the detection of bacterial endocarditis.

Eleven patients with a clinical diagnosis of bacterial endocarditis underwent scintillation scanning of the precordial region 2-7 days after the intravenous administration of 3 mCi of gallium-67 citrate. Seven had positive scans, 3 of which were confirmed by postmortem imaging at autopsy. Serial images revealed the scans to be frequently negative at 48 hours and positive from 3 to 8 days following injection. Uptake was not seen in the region of the myocardium 48 hours or longer after the injection of 15 patients without endocarditis used as controls.


The relationship between radiographic findings and asymmetrical radioactivity in the shoulder.

A prospective study was performed to compare asymmetrical radioactivity in the shoulder on 99mTc bone scans with the conventional radiographic findings of 100 right-handed and 8 left-handed patients. Of the 100 right-handed patients, 30 had increased radioactivity in the right shoulder; 5 showed increased radioactivity on the left. Clinical history, shoulder physical examination, and site of injection did not influence the frequency of asymmetrical radioactivity; only dominant handedness correlated with this finding.


The medial pneumothorax.

The intrapleural air of a pneumothorax may largely collect medial to the anterior aspect of the lung in supine infants. The mechanical basis for this phenomenon is presented with supporting experimental evidence. This distribution of intrapleural air poses problems in recognition of the pneumothorax radiographically, in differentiation of the pneumothorax from pneumomediastinum, in estimation of the true volume of intrapleural air, and in the proper placement of drainage tubes. The importance of horizontal-beam lateral radiographs and of careful attention to the position of intrapleural tubes is emphasized, especially in supine, immobile newborns.


Radiological quiz.

The authors report a case of Letterer-Siwe syndrome presenting primarily as a mediastinal mass erroneously diagnosed as cystic thymoma. Although thymic involvement in Letterer-Siwe syndrome is common, only 2 previous cases have involved a mediastinal mass.


Ultrasound assisted amniocentesis in prenatal genetic counseling.

Pre-amniocentesis ultrasonic placental localization and fetal age determination have greatly facilitated genetic counseling by helping to reduce the morbidity of the procedure and by providing an accurate gestational age. The indications for amniocentesis, a technique to indicate the best site for the procedure, and results in 33 patients are discussed.


Ultrasonic visualization of an umbilical vein.

A patent umbilical vein was demonstrated via ultrasound in a patient with portal hypertension. Ultrasonographic differential diagnosis of intra- and juxta-hepatic veins is given, with emphasis on real time ultrasonography.


Multiple lymphangiomas of the neck, axilla, mediastinum, and bones in an adult.

Whereas lymphangiomas of the neck, axilla, or mediastinum are not uncommon in children, they are rarely found in the adult, and primary lymphangioma of bone is very rare. The authors report a case of multiple lymphangiomas of the neck, axilla, mediastinum, and bones in a 34-year-old man, which they believe to be only the second such case reported thus far.


Unilateral pulmonary edema. An unusual complication of nitrogen mustard therapy.

Unilateral pulmonary edema developed in a 48-year-old woman following intrapleural nitrogen mustard instillation. Despite progressive infiltration, the patient's symptoms resolved spontaneously.


Visual complications following irradiation for pituitary adenomas and craniopharyngiomas.

Of 55 patients with pituitary adenomas or craniopharyngiomas treated with irradiation, a retrospective study revealed that 5 sustained a visual loss compatible with radiation damage to the optic nerve. No patient who received less than 250 rads/day fractions showed such visual loss. Within the range of total dosages used in this series, total dose was not an important determinant of this complication. The time to occurrence of visual disturbance ranged from 5 to 34 months following therapy.


Performance evaluation and quality assurance of computed tomography scanners, with illustrations from the EMI, ACTA, and Delta scanners.

Performance evaluation of equipment for computed tomography (CT) involves the integration of: (a) establishing performance criteria; (b) designing and implementing test procedures; and (c) reconciling test results in terms of desired performance. Precision (noise), contrast scale, linearity, accuracy, spatial independence, spatial resolution, artifacts, reproducible performance, and patient exposure are several parameters discussed, as are problems of measurement with regard to non-water bath scanners. Performance and quality control tests for the ACTA, Delta, and EMI scanners are outlined. Guidance for the prospective purchaser of CT equipment is presented as a summary of the ideas discussed.


Comparative modulation transfer functions of the EMI and Delta scanners.

Spatial resolution of the EMI and Delta computed tomographic scanners has been measured by recording the response to a nylon and water sunburst phantom (Siemens star) and calculating the modulation transfer function at radii corresponding to various spatial frequencies. The resolution appears to be related primarily to the size of the matrix element, and exhibits an upper cut-off frequency somewhat in excess of 3 cycles/cm.


The retrotracheal space.

The retrotracheal space may be abnormal when a frontal chest radiograph is normal. Common abnormalities, seen usually on the lateral view, are widening of the anterior soft tissue stripe separating the tracheal air column from the clear space behind it, and a mass density overlying the space. A barium esophagram generally facilitates the diagnosis.


Tissue chemical analysis with muonic x rays.

The stopped muon channel at the Clinton P. Anderson Meson Physics Facility was used as a source of muons for studying the elemental composition of tissue via muonic x rays. The x-ray spectra from several types of tissue were used to determine the amounts of carbon, nitrogen, and oxygen present. These determinations agree with the results of more conventional chemical analysis. Muonic x rays offer a noninvasive technique for determining the amounts of the more abundant elements in selected regions of the body.


Minute mucosal patterns in gastric carcinoma. Magnification radiography of resected gastric specimens.

Magnification radiographs of 32 resected gastric specimens were used for analysis of minute gastric mucosal patterns according to the size and shape of the gastric areas and the appearances of the sulci between them. The mucosal patterns of 92 portions of stomachs were divided into 5 types and observed for correlation with their macroscopic appearances and histology. Destruction of the gastric areas and the sulci was predominant in the carcinomatous mucosa. However, among the patterns of noncarcinomatous mucosa, 18% of those with marked mucosal atrophy had abnormal mucosal patterns impossible to distinguish from carcinomatous mucosa.


Clinical evaluation of electron radiography. Current status.

Details of a 4-phase evaluation of electron radiography are reported. The experimental equipment now uses liquid toners which result in less edge contrast and latitude than in powder-cloud exposures. Use of a bias technique during development prevents deposition except to areas where voltage exceeds the bias voltage. Quality radiographs with decreased doses and expense result.


Post-lymphographic percutaneous fine needle biopsy of lymph nodes guided by fluoroscopy.

Fine needle, percutaneous aspiration of suspect lymph nodes was carried out in 29 patients during fluoroscopy. The correct positioning of the needle was assured if the node moved with the tip of the needle. In 29 patients, there were 65 successful aspirations and 29 failures. Anesthesia is recommended but care should be taken that the anesthetic does not reach the lymph node itself as this can cause distortion of the cells.


Peripheral angiograph enhancement by long leg pneumatic boots.

In patients with arterial occlusive disease it is virtually impossible to predict the speed of blood flow due to the presence of stenoses, occlusions, and collaterals. Repeated exposures and injections can be avoided by the use of pneumatic boots which increase peripheral blood flow by reactive hyperemia, are well tolerated by patients, and decreases the pain associated with injection of contrast material.


Effects of negative pi mesons on mouse bone marrow cells.

Mouse bone marrow cells exposed in vitro to graded doses of negative pi mesons at 3.5-6.0 rads/min. gave Do values of 160 rads in the plateau (0.6 and 12.0 cm), and 130 rads in the peak (16.5 and 18.4 cm). Survival curve shoulders were narrow, with Dq values of 25 and 15 rads for plateau and peak positions. Gamma rays from 60Co at 4.5 rads/min. produced a curve with wider shoulder but steeper slope such that the RBE was essentially 1 for single doses between 100-400 rads.


Feasibility of coronal views in computed scanning of the head.

With some models of computerized scanners, it is possible to obtain not only axial, but also coronal tomograms. This is feasible because a water bag is not used and limited tilting capacity is built into the gantry. The head is extended and the central ray directed perpendicularly to the base of the skull. The resulting views, orthogonal to the conventional axial views, furnish important complementary information.


Computed coronal tomography.

A method for obtaining coronal scans of the cranium is described in which a scanner with a tilting gantry is used. Computed coronal tomography is especially useful in the high convexity area and in the suprasellar and foramen magnum regions.


Pulmonary manifestations of blastomycosis. Radiological support of a new concept.

The pulmonary manifestations of blastomycosis were observed in 51 patients and correlated with their location in the lungs and the clinical appearance of the patient. Blastomycosis is primarily an airbone infection that occurs in both acute and chronic forms and follows a specific pathway within the lungs. It must be strongly considered in the differential diagnosis of pulmonary lesions in geographical areas endemic to the disease.


Intrapulmonary effusion. Effect of expiration on the pseudodiaphragmatic contour.

The pseudodiaphragmatic contour of infrapulmonary effusion may differ from the contour of an elevated hemidiaphragm in the frontal view in that its medial portion is straight and shows a gradual inclination upward and laterally from the cardiac shadow, so that its apex is located more laterally. Previous studies have indicated that this configuration is seen only in about 50% of cases of infrapulmonary effusion. Using expiration radiographs, it is possible to routinely demonstrate this characteristic pseudodiaphragmatic contour. This study provides an additional sign of infrapulmonary effusion and aids in the explanation of the pseudodiaphragmatic contour.


Right colonic adhesions.

Adhesive bands may cause narrowing of the colon. The radiographic appearance may show evidence of a sharp, localized narrowing and smooth mucosal contour. Adhesions involving the ascending colon may also precipitate acute colonic obstruction due to formation of a cecal bascule. The nature of the adhesive bands and their relationship to prior surgery, to anomalies of mesenteric fixation, and to appendices epiploicae are discussed.


The biliary and urinary excretion of iopanoic acid: pharmacokinetics, influence of bile salts, and choleretic effect. An experimental study in bile-fistula dogs.

The biliary and urinary excretion and the choleretic effect of iopanoic acid (Telepaque) were studied in nonanesthetized bile-fistula dogs using a stepwise increase of infusion rates of iopanoic acid and a constant infusion of sodium taurocholate at a rate of either 0.5 or 2.0 mumoles/min./kg. The maximum rate of bile excretion (0.671 mumoles/min./kg) when taurocholate was infused at the lower rate nearly doubled (1.325 mumoles/min./kg) when given at the higher rate. Maximum biliary concentrations of iopanoic acid at both rates of taurocholate infusion (70-77 mumoles/ml) were almost double the maximum concentration previously determined for iodipamide (Cholografin) (42 mumoles/ml).


A new, simple test for thrombogenicity.

A simple technique is described to test thrombogenicity in dogs. Materials to be tested are introduced percutaneously into the femoral arteries of dogs in the form of a No. 5 catheter which is advanced to the aortic bifurcation. Another catheter can be introduced into the contralateral femoral artery in order to test two different materials in the same animal at the same time. After the catheter has been exposed to arterial blood for one hour, it is removed with a large-bore retrieval system, and all fibrin deposits are collected in a plastic basket. Significant thrombus formation was almost uniformly present in over 100 control studies. The technique has the advantage of being relatively noninvasive, allowing the testing of several materials in the same animal and yielding consistent results.


Localized amyloidosis of the ureter.

A case of localized amyloidosis of the distal ureter in a 51-year-old man is described. Pertinent features of previously reported cases are described, and the difficulty of distinguishing this entity from primary carcinoma of the ureter is discussed.


Reticular neovascularity in malignant and inflammatory renal masses.

Experienced angiographers were asked to differentiate malignancy from inflammatory disease on arteriograms of 37 renal masses containing fine reticular neovascularity, as opposed to the coarser, more irregular vessels typical of hypernephroma. The rate of accuracy was only 58%. Distribution of vessels chiefly around the periphery of the mass was associated with a diagnosis of inflammatory disease in all 6 patients with this finding; this was the sole criterion which proved to be helpful in making the distinction. The authors feel that when arteriography reveals reticular neovascularity, differentiation between malignant and inflammatory renal masses may be difficult or impossible and that the term "tumor vascularity" should be avoided in such situations.


Resorption of the undersurface of the distal clavicle in rheumatoid arthritis.

An elongated erosion on the undersurface of the distal clavicle, adjacent to the coracoid process, may be seen in the shoulder of a patient with rheumatoid arthritis. This finding is apparently related to inflammatory changes in the coracoclavicular ligament. Such an erosion may occur with or without additional radiographic alterations and, although not entirely specific, suggests rheumatoid arthritis.


Lisfranc's tarsometatarsal fracture-dislocation.

Lisfranc's fracture-dislocation is an injury at the tarsometatarsal joints. Usually the metatarsals dislocate dorsally and laterally. These frectures can be subtle, and a knowledge of the normal relationships is essential. Review of foot radiographs indicated that the most constant normal relationship of the tarsometatarsal joints is the alignment of the second tarsometatarsal joint, which, fortunately, is involved in most Lisfranc's dislocations. There is more variation in normal alignment of the other tarsometatarsal joints, but gross abnormalities are detectable, and the presence of associated chip fractures and clinical correlation will usually clarify more subtle cases.


Eosinophilic gastritis. Radiologic-pathologic correlation (RPC) from the Armed Forces Institute of Pathology (AFIP).

Eosinophilic gastroenteritis may involve the gastrointestinal tract locally ofr diffusely. When localized to the stomach, the preferred terminology is "eosinophilic gastritis". Pathologically, this entity is characterized by a high eosinophil count (which closely follows the symptomatology) and diffuse infiltration of the antral wall by eosinophils. Typical roentgenographic manifestations include gastric antral rigidity, thickened folds, and mucosal nodules. The differential diagnosis is discussed. Correct diagnosis is vital because of the benign nature of the disease and good response to conservative therapy.


Pneumatosis coli secondary to acute appendicitis. Case report.

An unusual case of pneumatosis coli is presented. The patient had acute inflammatory disease with gangrene of the appendix associated with air within the wall of the contiguous right colon.


The cervicothoracic continuum.

The anatomic communications between the neck and the mediastinum are described. Anatomic sections and drawing are used to demonstrate the normal compartments, their fascial envelopes, their contained structures, and their interrelationships. Selected cases are used to illustrate the spread of pathologic processes within the cervicothoracic region.


The radiology of the superior intercostal veins.

The superior intercostal veins define the pleural reflections of the caudad extent of the posterior junction line. They are paired structures which drain the first three intercostal spaces and join the azygous on the right and the accessory hemiazygous on the left. Because of their location posterior and lateral to the esophagus and trachea, their pleural reflections may be altered early in the course of a focal nodal disease of the posterior mediastinum.


Radiological features of mixed connective tissue disease and scleroderma--systemic lupus erythematosus overlap.

The radiological, clinical, and laboratory features found in seven patients with scleroderma-SLE overlap, including three with mixed connective tissue disease (MCTD), are described. There were no distinctive roentgenographic features which differentiated those with MCTD from the others with a clinical overlap syndrome of scleroderma and SLE. When features of both coexist in a single patient the radiologist may be the first to suggest the correct diagnosis of overlap syndrome of MCTD.


Radiographic distribution of intrathoracic disease in previously untreated patients with Hodgkin's disease and non-Hodgkin's lymphoma.

An analysis was made of the incidence of various intrathoracic abnormalities noted on plain chest radiographs and tomograms in a consecutive series of 300 patients with untreated Hodgkin's disease and nonHodgkin's lymphoma. Those with Hodgkin's disease have a higher incidence of intrathoracic disease at presentation than those with non-Hodgkin's lymphoma (67% vs. 43%). Bulky superior mediastinal lymphadenopathy is the hallmark of Hodgkin's disease. Lung involvement was more common in Hodgkin's disease (11.6% vs. 3.7%) and was always accompanied by mediastinal and/or hilar lymphadenopathy.


Intrathoracic manifestations of amyloid disease.

Nine cases of intrathoracic amyloid disease have been reviewed. A brief summary of historical material is presented along with detailed descriptions of the more pertinent cases. Observations suggest that a classification of the radiographic manifestations is needed with stress on massive calcific lymph node enlargement and a pulmonary lesion characterized by aggregations of small nodules.


Roentgen recognition of enlarged hilar lymph nodes: an anatomical review.

A new anatomical classification of the hilar lymph nodes, and their usual roentgen distribution, is presented, along with the most appropriate radiographic techniques for their demonstration. The characteristic roentgen appearances of enlarged hilar lymph nodes in various locations are correlated with the differential diagnoses. The appearance of a rounded lobulated mass is the typical radiographic finding of total hilar enlargement. The diagnosis of hilar nodal enlargement is best made from lateral body section radiographs.


The evaluation of pathologic alterations of juxtaosseous soft tissue by xeroradiography.

Xeroradiography proved extremely helpful in (a) evaluation of soft-tissue masses of both the axial and appendicular skeleton; (b) quantifying soft-tissue changes in advanced rheumatoid arthritis; (c) evaluation of bony involvement by an adjacent soft-tissue tumor or infection; (d) evaluation of rib lesions or rib integrity; and (e) assessment of bones in casted extremities. The technique was not helpful in the following conditions: early soft-tissue changes of rheumatoid arthritis; detection of minimal skeletal trauma; arthrography of the knee; evaluation of any portion of the vertebral column; evaluation of submandibular neck masses; or assessment of abdominal films for visceral structures.


Use of substrate-coated barium sulfate tablets in the evaluation of digestive enzyme deficiency.

In vitro and in vivo studies determined the effect of digestive enzymes on substrate-coated barium sulfate tablets. Fragmentation of the barium tablet core was detected radiographically after enzymatic digestion of the substrate material occurred. Preliminary studies in humans suggest that such tablets may be used in the diagnosis of pancreatic exocrine insufficiency.


Double tracking in the sigmoid colon.

Double tracking of barium in the sigmoid colon has been associated with granulomatous colitis by some; others consider it a sign of peridiverticulitis. Patients who showed no evidence of inflammatory disease elsewhere in the large intestine were analysed. The pathological diagnosis was diverticulitis in 29 of 35 cases, and granulomatous diverticulitis in only 1. In 5 the underlying process was perforated carcinoma of the sigmoid colon. In those with paracolonic sinus tracts due to peridiverticulitis, pathological study demonstrated tracts extrinsic to the muscularis and usually traceable to a perforated diverticulum. Long-term follow-up disclosed no evidence of subsequent inflammatory bowel disease.


Fatal aspiration of thick barium.

The authors report a case of fatal aspiration of thick barium during esophagography in a 75-year-old woman. Apparently the patient held much of the barium in her mouth and then aspirated it as she tried to swallow. The authors suggest that thick barium be avoided when fluoroscopy shows that the patient has difficulty in swallowing thin barium and that a suction machine equipped with a large-bore catheter be readily available during esophagography, particularly in the elderly or obtunded patient.


Hodgkin's disease of the rectum.

In a rare case of Hodgkin's disease of the rectum, plain films of the abdomen revealed splenomegaly, and fluoroscopy demonstrated anterior displacement of the stomach and duodenum, believed to be secondary to enlarged lymph nodes. Fluoroscopic examination of the colon showed a large, annular constricting lesion with nodular-appearing mucosa.


Hepatic lymphatics as opacified by percutaneous intrahepatic injection of contrast medium. Analysis of hepatic lymphograms in 125 cases.

Hepatic lymph vessels were opacified in 125 patients with various hepatobiliary diseases during percutaneous transhepatic cholangiography or portography. Contrast medium deposited in the parenchyma flowed relatively quickly in winding channels, usually toward the hepatic hilus. No correlation was demonstrated between the locus of the intraparenchymal deposit and the direction of the flow. Contrast medium also opacified the lymphatics near the hepatic hilus and abdominal aorta. Neither jaundice nor liver disorder were prerequisite for the visualization of the hepatic lymphatics. The intrahepatic injection of contrast medium provides a safe and useful method for the study of hepatic lymph and its pathways.


Malignant giant cell tumor of the soft tissue: angiographic manifestations.

Two cases of malignant giant cell tumor originating within the soft tissues of the thigh are reported. In both instances, angiography demonstrated hypervascular masses with arterial and venous abnormalities indicative of an aggressive malignancy. The histopathologic appearance of the lesions was similar to that of osseous giant cell tumors. The clinical and radiographic features of this rare entity are briefly reviewed.


Observations of radionuclide imaging in hypertrophic pulmonary osteoarthropathy.

99mTc pyrophosphate was employed in the study of patients with hypertrophic pulmonary osteoarthropathy. Several facts emerge when comparing the radionuclide, radiographic and clinical findings. Radionuclide imaging reveals the presence and extent of subperiosteal activity with greater clarity than does radiography. Synovitis associated with the syndrome is readily disclosed, and the regression of the skeletal manifestions following excision of the pulmonary lesion can be documented.


Manifestations of hypertrophic pulmonary osteoarthropathy in patients with carcinoma of the lung. Demonstration by 99mTc-pyrophosphate bone scans.

Two patients with carcinoma of the lung were studied with 99mTc-stannous pyrophosphate. Resolution of scintigraphic activity was observed postoperatively in one patient, while the second patient showed an asymmetric pattern of radionuclide uptake and radiographic changes as well as clinical findings of hypertrophic pulmonary osteoarthropathy.


Bronchial adenoma causing unilateral absence of pulmonary perfusion.

This case of bronchial adenoma is used as a clinical model demonstrating absence of pulmonary perfusion by 131I-MAA scanning secondary to bronchial obstruction. Radiographic and radionuclide studies are correlated and other causes of pulmonary hypoperfusion discussed. The literature and related cases are reviewed.


Mesenteric vasculature masquerading as a kidney at renal imaging.

A case is described in which mesenteric vasculature simulated a perfused left kidney during the dynamic renal imaging of a patient who had undergone a prior left nephrectomy. Confirmation was provided by abdominal angiography.


Malposition of the colon in left renal agenesis and ectopia.

The anatomic splenic flexure of the colon occupies the renal fossa in patients with left renal agenesis or ectopia and presents a characteristic appearance on radiographs and contrast enema studies. If excretory urography fails to reveal the left kidney, demonstration of the normal colon will exclude renal agenesis or ectopia. The colon remains in normal position in patients with left renal dysplasia or after left nephrectomy.


Retention cysts of Cowper's duct.

Retention cysts arising from obstructed Cowper's ducts are rare lesions of the anterior urethra. Five cases are reported, 3 in male infacts and 2 in young boys. In children and adults the cysts may cause dysuria, urinary frequency, or urinary retention. The etiology of Cowper's duct cysts remains uncertain, but both congenital and acquired cysts have been described. The radiographic findings are characteristic: a smooth, rounded filling defect is seen on the ventral wall of the proximal bulbous urethra during voiding cystourethrography. After fulguration of the cyst, urethrography may reveal reflux into a dilated Cowper's duct.


Gray-scale ultrasonography of the thyroid.

Gray-scale ultrasonography of the thyroid was performed in 33 patients, utilizing a commercially available scanning unit and an aqueous gel coupling medium. Solid and cystic lesions could readily be differentiated, but it was impossible to tell benign lesions from malignant tumors. The ultrasound appearance of thyroid cysts, adenoma, goiter, and carcinoma is illustrated.


New technique for ultrasound imaging.

A new system of ultrasonic imaging has been developed which utilizes optical interferometry. This system has a broad frequency range, wide angular response, and good resolution. Operation of the system and the results of experimental imaging are described. Application of this technique to the evaluation of in vitro tissue specimens demonstrates its capability for characterization of ultrasonic tissue properties.


Approaches to optimization of dose in radiation therapy of cervix carcinoma.

A treatment planning approach to radiation therapy for carcinoma of the cervix which attempts to maximize tumor dose and minimize the effect on normal tissue must include additonal dose reference points besides the standard ones (Manchester points A and B, mg-hrs.) A variety of loading configurations can be used to treat the tumor volume to a specified dose. In order to avoid inappropriate loading arrangements, dose at the tumor and at the vault must be carried to required therapeutic levels.


Control of dose administered once a week and three times a day according to schedules calculated by the CRE formula, using skin reaction as a biological parameter.

Patients with breast cancer were irradiated postoperatively to bilateral parasternal fields. The validity of the Cumulative Radiation Effect (CRE) formula for treatment once a week and three times a day was analyzed, and both schedules were compared with treatment once a day (five times a week). The biological radiation effect on normal tissue was studied by reflectance spectrophotometry of skin erythema and pigmentation. Early skin reactions were identical after irradiation daily and once a week, respectively, but were found to be significantly more pronounced after irradiation three times a day than after treatment once a day, corresponding to an overexposure of 7-10%.


Performance specifications for diagnostic x-ray equipment.

The specification of performance characteristics for diagnostic x-ray equipment involves an interplay between purchaser and supplier which often results in inadequate understanding of imaging requirements by the supplier, and unfulfilled expectations by the purchaser. A statement of performance specifications has been prepared and accompanies requests for bids distributed to suppliers. The statement is described in its general form; modifications bay be needed to adapt it to a specific radiographic system.


The modification of gastrointestinal tolerance and responses to abdominal irradiation by chemotherapeutic agents.

Groups of male DBA/2 mice were irradiated with partial abdominal exposures of x radiation ranging from 100 to 1,600 rads. Concomitant with radiation exposure and at 1 or 4 hours prior to, and at 1, 6, 24, or 48 hours after irradiation, various chemotherapeutic agents were administered, i.e., methotrexate, Cytoxan, adriamycin and BCNU. The results suggest that excessive gastrointestinal toxicity may result if aggressive chemotherapy is closely spaced with radiation exposure for the treatment of abdominal neoplasms. However, adjustment of dose and time patterns based on the proliferative responses of the mucosa may circumvent such toxicity to a large extent.


Image characteristics of liquid developed electron radiographs.

This paper presents electron radiograph studies using the new Xonics liquid development system described only briefly previously. Results indicate: (a) higher contrast images with reduced but useful edge enhancement; (b) adjustable contrast; (c) reduced exposure vs. aerosol development; (d) sharp, low artifact images to densities greater than 2.5; and (e) possibility of nongrid scatter control in some situations.


Percutaneous antecubital transvenous cholangiography. A modified technique using a flexible needle.

A percutaneous antecubital transvenous cholangiography technique using a flexible 20 gauge needle is described. The porcedure was successful in 6 patients with obstructive jaundice but failed in 2 patients without bile duct dilatation. The authors feel that this technique is easier and safer than present transvenous methods. Modifications for the femoral approach and use of the technique in pediatric patients are described.


Portal vein visualization during intravenous cholangiography.

The portal vein (PV) was frequently visualized during infusion intravenous cholangiography with tomography. Although visualization was usually faint, the PV was occasionally seen as well as or better than the common duct (CD). Occasionally, there is sufficient periportal fat to enable PV visualization without contrast material, but PV visualization is probably usually due to a combination of faint venous opacification and surrounding periportal and omental fat. If unrecognized, the opacified portal vein may occasionally be mistaken for a dilated common duct.


Breast cancer screening. Benefit and risk for the first annual screening.

Of 96 cancers which have been detected as a result of the first annual screening of 10,470 volunteers, 46 have been clinically occult. Forty-one of these have been Stage 1 or less carcinoma, and 26 of these 41 have been minimal cancer. For the radiographic parameters used, the benefit of detecting these cancers vs. the risk of induced cancer is estimated as 103:1 and 65:1, respectively.


Gated blood pool imaging following 99mTc stannous pyrophosphate imaging.

Cardiac patients who have undergone 99mTc-stannous pyrophosphate (99mTc-PYP) myocardial imaging can be injected 24 hours later with 99mTc-pertechnetate (99mTc04) to assess left ventricular function. Reduction of 99mTc04 by tin remaining in the blood following the stannous pyrophosphate injection causes labeling of the red cells by 99mTc04 and the creation of a vascular tracer suitable for electrocardiographically gated imaging.


Shaping of isodose curves in intracavitary irradiation using the afterloading method. A feasibility study involving mathematical simulation.

The possibility of adjusting the irradiation scheme to shape the isodose curve around an intracavitary source arrangement was studied mathematically. The total number of millicurie hours of irradiation for each source position was derived by a linear programming approach, taking into account the shape of the tumor in three different cases. The practical isodose curves obtainable with the source arrangement chosen were compared with the shape desired.


The relative biological effectiveness (RBE) and oxygen enhancement ratio (OER) of neon ions for the EMT6 tumor system.

EMT6 tumors were exposed to neon ions in vivo and in vitro in the plateau and spread-out Bragg peak regions of the beam. The RBE in vivo was 1.7-2.1 in the plateau region and 2.6-2.9 in the Bragg peak; the OER was 2.0 and 1.4, respectively. Neon ions have great potential in the radiotherapy of tumors because of their decreased OER and excellent depth-dose distribution in tissue.


Is this radiograph really necessary?

While agreeing that overutilization of radiological diagnosis creates an unnecessary increase in both medical costs and patient exposure, the author calls for a more sensible and economical approach to the number of radiographs taken as part of any given study, noting that in many cases the number could be cut in half without any loss of diagnostic efficiency. By limiting the number of views per study, the radiologist would be able to remain in a safe medico-legal situation without reducing his ability to function as a diagnostician.


The incidence of hiatal hernia in infants and children. Results of a survey of members of the Society for Pediatric Radiology.

A questionaire regarding the incidence of hiatal hernia in infacts and children was sent to the 50 largest departments of pediatric radiology in the United States and Canada. The 36 returned revealed that the larger departments see an average of 3.2 hiatal hernias per year or about 0.62 per cent of their upper gastrointestinal studies.


Correlation between release of free arachidonic acid and prostaglandin formation in brain cortex and cerebellum.

Levels of free arachidonic acid and of prostaglandin F2alpha and E2 have been measured in both brain cortex and cerebellum of rats killed by focussed microwave irradiation, and after decapitation followed by ischemia. The same parameters were studied during incubation assays. It was found that: a) after ischemia levels of both free arachidonic acid and of prostaglandins in cerebellum are lower than in brain cortex, b) formation of prostaglandins from endogenous precursor in incubated cortex is higher than in cerebellum, c) release of free arachidonic acid occurs mainly during the time interval between the sacrifice of the animals and the beginning of the incubation, whereas prostaglandins are formed mainly during the incubation assay. The correlation between release of free arachidonic acid and prostaglandin formation is discussed.


Effects of hypoxia on the hemodynamic actions of prostaglandin E1.

The effect of prostaglandin E1 (PGE1) on central and peripheral hemodynamics was studied in seven conscious dogs under conditions of normoxia and hypobaric hypoxia to ascertain if hypoxia attenuated the cardiovascular actions of PGE1. Silastic catheters were chronically implanted in the pulmonary artery, left atrium, and aorta. Acute hypoxia was produced in a hypobaric chamber maintained at 446 mmHg pressure (14,000 feet). PGE1 at sea level (normoxia) resulted in significant increases in heart rate, cardiac output, left ventricular stroke work and pulmonary blood volume as well as significant decreases in aortic, pulmonary arterial, and left atrial pressures. During hypobaric hypoxia, PGE1 produced essentially identical effects on all hemodynamic parameters except pulmonary blood volume and pulmonary arterial pressure where marked attenuation of PGE1 action occurred.


Enteropooling assay: a test for diarrhea produced by prostaglandins.

An assay (enteropooling assay) to test the diarrheogenic property of prostaglandins is described. Fasted rats are given a prostaglandins either orally or subcutaneously, and are killed 30 min later. The entire small intestine is removed and its contents collected into a test tube. The greater the volume of this intestinal fluid, the more diarrheogenic is the prostaglandin. The assay is simple, rapid, quantitative, and predictive of diarrhea. It can be used to grade the relative diarrhoegenic activity of prostaglandins as well as to test agents that may block this effect. The accumulation of fluid into the small intestine is called "enteropooling". It is the sum of (a) the fluid being excreted from the blood into the lumen, and (b) to a lesser extent, the portion of fluid already into the lumen but whose absorption is inhibited by the prostaglandin. The degree of enteropooling depends also on how much fluid flows from the small to the large intestine. Our results support the hypothesis that the diarrhea observed after administration of high doses of prostaglandins is due to accumulation of abundant fluid into the small intestine, and not intestinal hypermotility. This fluid is then carried into the large intestine and eventually expelled as diarrhea. Agents other than prostaglandins were tested for enteropooling activity. Laxatives such as castor oil, hypertonic solutions and bile salts caused enteropooling.


Inhibitory actions of polyphloretin phosphate and related compounds on the response to prostaglandin in the smooth muscle of guinea-pig stomach.

The inhibitory actions of polyphloretin phosphate (PPP) and related compounds, di-4-phloretin phosphate (DPP), PHLORETIN AND TRIHYDROXY PROPIOPHENONE (THPP) on the contractile responses to prostaglandin (PG) and acetylcholine (ACh) in longitudinal smooth muscle of guinea-pig stomach were studied. Of the four inhibitors PPP and DPP showed relatively selective antagonism for PGE1. DPP gave the highest pW2 value against PGE1. These results indicate that DPP is a useful antagonist of PG in smooth muscle, although it slightly inhibits responses to ACh, 5-HT or histamine, and the Ca-induced contracture in K depolarized preparation.


Experience with 276 intra-amniotic prostaglandin F2alpha induced midtrimester abortions.

Induction of midtrimester abortion using 40 mg intra-amniotic prostaglandin F2alpha was performed on 276 patients. Gestational age and fetal status had no effect on injection-to-abortion time while multiparity and the concomitant use of laminaria appeared to decrease the abortion time. The side effect and complication rates were acceptable and the results compare favorably with those of other midtrimester abortion techniques.


Labour induction using buccal prostaglandin e2.

Prostaglandins may remain in the circulation for some two hours after oral therapy and any resultant hypertonus may be difficult to treat in these circumstances. Buccal administration based on the concept that tablets could be discarded should this occur, has been evaluated in 30 patients. Effective uterine stimulation occurred in 90% of subjects receiving a dose of 1mg hourly. No hypertonus occurred but two patients had a prolonged contraction on a single occasion during labour. The fact that the tablets dissolve rapidly and in addition produce an unpleasant buccal prostaglandins do not have advantages over alternative methods of oxytocic administration.


Temporal changes in circulating steroids during prostaglandin  F2alpha induced abortion in the rat and rabbit.

The serum levels of progesterone (delta4P), 20alpha-dihydroxyprogesterone (20alpha-DHP), pregnenolone (delta5P) and estrogens at different time intervals during Silastic-PVP-PGF2alpha tube induced midterm abortion were measured by radioimmunoassay in the rat and rabbit. The concentrations of delta4P and delta5P were significantly reduced but that of 20alpha-DHP was increased significantly as early as 20 hours after PGF2alpha treatment. Estrogen levels showed slight reduction in the rat but remained unchanged in the rabbit. The ratio of delta4P/20alpha-DHP recorded were 2.15 and 16.86 (pretreatment) and dropped to 0.08 and 0.37 (60 hours after insertion of Silastic-PVP-PGF2alpha tube) in the rat and rabbit, respectively. These findings suggest that the suppression of circulating delta4P by PGF2alpha might be the result of a reduced precursor (delta5P) pool size as well as changes in the enzymic systems responsible for the formation and conversion of delta4P. It is still to be determined if changes in estrogen levels in the rat have any bearing on abortion induced by PGF2alpha.


Plasma levels of the methyl ester of 15-methyl PGF2alpha in connection with intravenous and vaginal administration to the human.

After intravenous injection of the methyl ester of 15-methyl-PGF2alpha the drug initially disappeared faster than the corresponding free acid, but still after one hour, about 1% of the active drug is circulating in plasma. Vaginal administration of single suppositories containing 1 mg of 15-methyl-PGF2alpha methyl ester and determination of plasma levels using gas chromatography-mass spectrometry demonstrated that the highest plasma levels were reached after 1.5-3 hours. Vaginal suppositories were administered according to different dose schedules for induction of abortion and plasma levels of 15-methyl-PGF2alpha and it's ester were determined. There seemed to be a gross correlation between given doses and obtained plasma level. The data will serve as basis for further development of vaginal delivery devices.


Prostaglandins, indomethacin and dysmenorrhea.

Uterine contractility was recorded during the period of menstruation in six dysmenorrheic women. A variable high tonus was observed in each case. Uterine recordings were repeated during the subsequent menstruation following pre-treatment with indomethacin at an oral dose of 75 mg or 200 mg per day beginning one day before the expected onset of menstruation. A lower uterine tonus was found in all indomethacin-treated cycles. Complete alleviation of spasmodic pain was obtained in the six subjects. The endogenous concentration of 15-keto-13, 14-dihydro PGF2alpha was determined by the gas chromatography-mass spectrometry method and observed to be relatively high in women with dysmenorrhea.


Serum hormone levels in women undergoing abortion with intra-amniotic, extra-amniotic or intra-muscular administration of 15(S) 15-methyl-prostaglandin F2alpha.

The serum levels of estradiol-17beta, progesterone and HPL have been estimated by specific radioimmunoassay in thirty women undergoing abortion with 15-methyl-PGF2alpha given by intra-amniotic, extra-amniotic or intra-muscular route. A significant decline in the levels of these hormones was observed in 27 cases in which the pregnancy was terminated. However, in the remaining three cases, 15-methyl-PGF2alpha was found to be unsuccessful, and no significant change in the hormone levels was evident. The decline in these hormones was more marked by intra-muscular route, than that observed by the other routes. The pattern of estradiol-17beta decline was more consistent when compared with progesterone and HPL. The levels of progesterone and HPL, in a few cases, rather showed an increase in the initial hours of 15-methyl-PGF2alpha administration before the decline began and this pattern was more prominent on extra-amniotic administration. In general, the decline in the hormone levels was slower in cases which took longer time for abortion than cases with shorter induction-abortion time (IAT). The decline in estradiol-17beta levels was about 65% at six hour of intra-muscular administration of 15-methyl-PGF2alpha, whereas the corresponding fall with intra-amniotic and extra-amniotic routes was 29 and 22%, respectively. However, the net drop in its levels during IAT was not significantly different (range 70 to 80%) by the three routes. About 38% fall in progesterone levels was observed at six hour of intra-muscular administration whereas, by intra-amniotic the fall was 19%. The net decline in progesterone levels, during IAT, was in the range of 46 to 60% by the three routes. Similarly, intra-muscular 15-methyl-PGF2alpha evoked a sharper decline in HPL levels as compared with other routes. The total decline during IAT was 58 to 66%. The results, thus indicated that the abortion with 15-methyl-PGF2alpha was associated with a fall in the serum hormone levels, which could be resultant effect of alterations in the hormone production by the foeto-placental unit. This along with the uterine contractions may play a significant role in the abortifacient action of 15-methyl-PGF2alpha.


Midtrimester prostaglandin-induced abortion: gross and light microscopic findings in the placenta.

A systematic gross and light microscopic study was done of 60 placentas, spontaneously delivered following induction by intra-amniotic PGF2alpha administration. The main findings were: high incidence of marginal and basal decidual hemorrhage, widespread degenerative changes in the decidua and chorionic villi, intervillous congestion and thrombosis and significant underfilling of the fetal vasculature. These changes are discussed in terms of the possible factors underlying the mechanism of prostaglandin-induced abortion.


Prostaglandins in the circulation of the fetal lamb.

Prostaglandin E and PGF have been measured in the plasma of chronically catheterized fetal lambs throughout the last 20-35 days (0.73 onwards) of gestation. The mean concentration of PGE was higher than that of PGF. There was a significant increase in the concentration of PGE but little change in the concentration of PGF in samples of fetal plasma taken within 24 h of parturition. In contrast, at this time in maternal utero-ovarian venous plasma, there was a large increase in PGF, but relatively little change in PGE. There was a significant decrease in the concentration of PGE and PGF in the plasma of lambs within 12 h after birth compared to the levels found in the same animals as fetuses a few hours previously. The physiological importance of these changes is discussed.


Prostaglandin E2: a factor in the pathogenesis of cholera.

Injection of cholera toxin in vivo into loops of intestine in rats caused the production of an exudate. This was found to contain prostaglandin E2 by assay on the rat stomach strip and by thin-layer chromatography. The amounts found ranged from 20 to 40 ng per loop of intestine. Introduction of 30 ng of prostaglandin E2 into intestinal loops caused the production of an exudate similar in volume to that found after the introduction of cholera toxin. These results indicate that the exudate in cholera is caused by the action of prostaglandin liberated by the enterotoxin. It is suggested that an inhibitor of prostaglandin release could be added to the solutions used in treatment for the restoration of fluids and electrolytes, with the object of blocking the action of toxin still present in the intestinal lumen, thereby achieving a more rapid therapeutic result.


Fatty acid and prostaglandin composition of left ventricular myocardium from dexamethasone-treated dogs with severe low output syndrome (LOS).

The effects of dexamethasone (DEX) administration on the left ventricular myocardial content of fatty acids and prostaglandins E1, E2 and F2alpha were studied. Following a complete right and left cardiac catheterization, either DEX (8 mg/kg) or an equivalent volume of its vehicle was given intravenously 30 minutes prior to low output syndrome (LOS induction, and supplemental doses of DEX (4 mg/kg) or vehicle administered at 15 and 75 minutes post-LOS induction. Low output syndrome was induced by intravenous administration of a myocardial depressor protein (MDP) which has been isolated from the venom of the Western diamondback rattlesnake, Crotalus atrox. Neither DEX nor its vehicle had a significant effect during the entire experiment, that is, in the normal or low cardiac output state in most of the hemodynamic parameters investigated. The three hour mortality rate for the DEX-treated animals was 22% (n=10) while that of the control group was 41% (n=26) indicating that the beneficial effects of this corticosteroid are not really apparent from hemodynamic evaluation alone. Since DEX only had a significant post-LOS induction effect in maintaining a lower left ventricular end-diastolic and pulmonary capillary wedge pressures, a higher arterio-venous oxygen saturation difference, and a more efficient contractile state of myocardial fibers (Vmax), an indirect correlation to coronary arterial blood flow at the subcellular level was sought. To this effect, prostaglandins and specific lipid classes of left ventricular myocardium (LVM) from control and LOS animals receiving either vehicle or DEX were analyzed. Low output state induction alone raised myocardial PG levels above those of sham-catheterized animals; on the other hand, dexamethasone induced a significant decrease in the three prostaglandins studied when administered to control (no LOS) animals. In the presence of LOS, however, dexamethasone overrode in part the increase in PGE1 and PGE2 brought about by LOS while in the case of PGF2alpha the LOS effect was totally prevented and its concentration was not significantly higher than in control animals receiving dexamathasone. LOS induction led to an increase in myristic and arachidonic acids and a decrease in palmitic and linolenic acids. Dexamethasone administration to control animals increased the concentration of stearic acid above all the other groups but decreased the concentration of linolenic acid when compared to DEX-treated animals with LOS or sham-catheterized animals. There were no significant differences in the total myocardial lipid among the four groups of animals studied. It is suggested that the potentially beneficial effects of corticosteroid administration to animals with low output syndrome are related to their effects on fatty acid and prostaglandin content of myocardium.


The behaviour of the pulmonary metabolites of prostaglandins in several simple thin-layer chromatography and bioassay systems.

The behaviour of the pulmonary metabolites of prostaglanding E1, E2 and F2alpha were examined in several thin-layer chromatography (TLC) systems commonly used to differentiate parent prostaglandins. Although the systems chosen readily distinguished between a prostaglandin and its own metabolites, they often did not differentiate between a parent prostaglandin and the metabolites of another. In particular, 13, 14-dihydro-PGF2alpha was virtually indistinguishable from PGE2 and 13, 14-dihydro-PGE2 was similarly indistinguishable from PGE1, in all systems investigated. These pairs of prostaglandins could not be distinguished by bioassay on the rat stomach strip alone. Although distinction could be made by parallel assay on the rat stomach strip, chick rectum and rat colon, the differential assay obtained would not be enough to allow identification of these prostaglandins and metabolites in samples containing their mixtures. The 13, 14-dihydro-prostaglandin metabolites were also active in contracting the isolated rat uterus. The findings indicate that TLC and bioassay together may not permit identification of prostaglandins in biological fluids.


A comparison of the bronchodilator activity of (+/-) 11-deoxy prostaglandin E1 with its 15-methyl analogue, (doxaprost).

The bronchodilator activity of (+/-) 11-deoxy prostaglandin E1 was compared to the activity of its (+/-) 15-methyl analogue, (doxaprost). Both compounds inhibited histamine-induced bronchoconstriction in the anesthetized guinea pig where changes in tracheal pressure were measured. Doxaprost was 73 and 32 times more potent that (+/-) 11-deoxy PGE1 by the aerosol and i.v. routes, respectively. Doxaprost also demonstrated a longer duration of effect. Both compounds decreased pulmonary resistance in the 5HT tonal cat. There was no difference in the potency of the two compounds. However, doxaprost had a longer duration of effect. Both compounds caused a fall in mean arterial blood pressure after i.v. administration in the guinea pig but not after aerosol administration in the guinea pig and cat. Both compounds caused relaxation of the isolated guinea pig tracheal strip when tone was induced with carbachol. There was no difference in the potency of the two compounds. The increased activity in vivo but not in vitro of the 15-methyl analogue doxaprost is consistent with a lack of enzyme inactivation.


Glass capillary columns applied to prostaglandins measurement: a useful tool for gas-chromatography mass spectrometry analysis.

The difficulties to analyse prostaglandins (PG) by gas-liquid chromatography are mainly due to the lack of sensitivity of the gas-chromatograph itself (higher than 200 ng) and to the poor resolution of the packed columns. Therefore the use of glass capillary columns which has been applied with success for other biological compounds was tempting. We describe a comparison of the preparation of the columns and their use for PG analysis of standards and of human semen. A complete resolution of PG-1 from PG-2 series was achieved. The sensitivity was multiplied 100 fold with a flame ionisation detector when compared to packed columns and was equal to the one obtained with electron capture detectors without the inconveniences of this technique. The successful coupling of glass capillary columns to a mass spectrometer leads to promising results and allows profile studies of primary PG and their metabolites as seen with human semen.


[Pre-systolic deflexion in pressure recordings of the right ventricle and pulmonary artery (author's transl)].

The authors demonstrated experimentally that the origin of the pre-systolic deflexion, previously observed by many investigators in pressure recordings of the right ventricle and the pulmonary artery, is due to the effective atrial contraction, which, besides the pressure change, produces a blood flow from the ventricle towards the artery. This flow must possibly exert an important role in the maintenance of the cardiac output when a failure of the right ventricle is established.


[Mathematical formula for calculating ventricular ejection volume by changes in intracardiac electric conductivity (author's transl)].

In the present paper a formula appropiate to stroke volume estimation in the experimental animal is presented. Based in the indicator concentration difference during the two diastoles which follows the indicator injection on the ventricle chamber, the electric conductivity through impedance recording indicates these concentration. Appropiate procedures and a calibrating scale are used in order to obtain these two concentrations. From the stroke volume which appears as changes in impedance measured between a pair of electrodes located at the apex and base of the ventricle and the data obtained through the formula, the cardiac output and ventricular volume can be calculated.


[Dispersion pattern of saline indicator on canine left ventricle (author's transl)].

The cardiac output evaluation is usually realized through indicator dilution techniques and this principle was applied to ventricular volume measurements. However this approach has been criticized by several workers. Based on the recently developed association of indicator dilution method with intraventricular impedance recording to cardiac output determinations, the present investigation was designed to analize the dipersion pattern of saline solution within the ventricle. Three bipolar eletrodes were placed in different positions on the left ventricle in order to record the duration in seconds, for the saline to reach these positions. The detection of the saline was done through conductibility changes at the eletrodes ends. The results indicate a time duration smaller to the indicator dispersion than those of the diastole duration, simultaneously measured.


[Differentiation of foetal and prepuberty leydig cell in electron microscope (author's transl)].

A morphometric study of intra-uterine and extra-uterine Leydig cell differentiation was carried out by the Weibel's technique which was adapted for morphometry on electronmicrography. The results obtained in rats, the animals studied in this investigation, were: a) Testis of intra-uterine life as well as those of extra-uterine life displayed Leydig cells with lipid droplets. b) The percentage of Leydig cells varied from one testis to another. c) This percentage increased at 20th day of intra-uterine life and between 60th and 90th day of extra-uterine life. d) The percentage of lipid droplets within cytoplasm of Leydig cell increased at 20th day of intra-uterine life, at 15th day of extra-uterine life and at the proximity of puberty. e) The percentages of mitochondria are at inverse ratio of percentage of lipid droplets until the 40th day of life.


[Effects of bilateral common carotid arteries occlusion on vagal activity (author's transl)].

The effects of carotid occlusion on parasympathetic activity were studied in anesthetized dogs, submitted to beta adrenergic blockade. Modifications of the heart rate, before and after administration of atropine, were utilized for assessment of vagal changes. When vagal activity was intact there was elevation of the heart rate. After parasympathetic blockade carotid occlusion did not cause heart rate modifications. The data suggest that carotid occlusion produced vagal inhibition.


Apgar score and blood coagulation factors.

Blood coagulation tests were performed in 93 newborn infants with different Apgar score at the 1st and 5th minutes of life. The laboratorial determinations were periodically performed at 0, 24 and 48 hours of life. The following tests were performed: bleeding time, whole blood clotting time, prothrombin time, kaolin-cephalin clotting time, thrombin time, dosage of factors I, V, VIII and X, clot retraction, platelet count, englobulin lysis time and the tourniquet test. Immediately after birth, the mean values of the blood coagulation factors were significantly different among the groups, with the exception of the whole blood clotting time and the platelet count. Those differences were due to the presence of the more depressed neonates. Although these results could indicate some degree of hepatic damage, it was apparent that an activation of the blood coagulation mechanisms took place, leading to a consumption coagulopathy. The infants who died (10) presented clinical and laboratorial data suggestive of disseminated intravascular coagulation (DIC). Necroscopic findings of microthrombosis in the liver and in the central nervous system were diagnosed in two infants.


[Right ventricle--pulmonary artery diastolic blood flow (author's transl)].

The authors show the possibility of the establishment of blood flow from the right ventricle to the pulmonary artery during the period of ventricular diastole, through experimental models mimetizing hemodynamic patterns described in the literature for certain cardiopathies. These models consisted of experimental hypodiastoly, associated or not with right ventricle hyposystoly. The detection of the existence or not of blood flow in the several phases of the cardiac cycle, was made recording the variations of the electrical impedance of the blood.


[Simplified techniques for toxoplasmosis studies (author's transl)].

Some improvements on laboratory technics for Toxoplasmosis are presented: 1--the use of serum from guinea-pigs as accessory factor (AF) on the dye-test; 2--the use of filter-paper discs for collecting and storing blood of children and small animals for the dye test; 3--conservation of Toxoplasma gondii at various media and temperatures. 1--the pool of serum from 14 guinea-pigs gave good results when diluted in 1/5 Alsever solution at the proportion of 6/10; 2--the blood from digital puncture usually could be collected on filter-paper discs of 15 mm of diameter and stored at the freezer to -23 degrees C for 3-4 weeks, protected with alumen-paper. The dilution with saline 8.5% could be made 1/2 hour before starting the procedure; 3--the Toxoplasma gondii (cysts and trophozoites) could be stored at LIT medium or saline 8.5% at refrigator a +4 degrees C for 15-22 days, with some reduction in virulence.


[Immunological and oxidase measurement of ceruloplasmin in pregnant women and newborn (author's transl)].

Ceruloplasmin measurements were made by oxidase and immunochemical methods in serum from three groups of people, normal, pregnant women and their newborns. Whatever the method ceruloplasmin showed a decrease in the newborns and an increase in pregnant women as compared with the normal controls. The three groups showed a significant correlation between both measurement. The correlation ratio between the two methods of measurement in the newborns is significantly different from the pregnant and the normal groups. It appears that ceruloplasmin in the newborns' serum has a lower oxidase activity per molecule than that from adult's serum.


[Effect of somatostatin on renin secretion in the isolated perfused rat kidney (author's transl)].

The effects of tetradecapeptide somatostatin on renin secretion has been studied in the isolated perfused kidney of the rat. The stimulation mediated by isoproterenol (7 X 10(-9) M), theophylline (10(-4) M) and PGE2 (10 ng/ml) was not inhibited by somatostatin (75 ng/ml).


[Constancy of total protein contents in various regions of the feline central nervous system (author's transl)].

A striking constancy of total protein content was shown in 45 regions of the feline CNS, recognized as markedly heterogeneous. The hypophysis differed from these tissues, due perhaps to its high blood element content. Synaptosomal fractions prepared from 17 regions of the CNS did not exhibit this constancy.


The serum ferroxidase system and the effect of estrogen on plasma iron.

Estrogen effects on plasma iron and ferroxidase activity in some mammals and domestic fowl are studied, to investigate a possible estrogen mechanism on iron through its action on the ferroxidase system. Although estrogen generally induces ceruloplasmin, iron mobilization, characterized by a rise in plasma iron, was evident only in rats and chickens. Gonadotrophin treatment confirmed these results. A decreasing affect on plasma iron was noted in rabbits and guinea-pigs, substantiated by some bibliographical data. Ferroxidase activity increased and a copper-dependent factor was evident in copper injected species. Iron mobilization, however, was produced only in rats and chickens. D-penicillamine treatment considerably lowered ferroxidase activity in rats and suppressed the estradiol increasing plasma iron effect. This response to the copper-chelating drug did not take place in the other species. This phenomenon could be explained by the presence of two copper-dependent ferroxidases (ferroxidase I or ceruloplasmin and ferroxidase II) in rat plasma, as recently published.


[Effect of vagal denervation on the alkaline phosphatases of the jejunal mucosa of the rat (author's transl)].

The results of experiments conducted on the qualitative (histochemical) and quantitative (biochemical) determination of alkaline phosphatase present in rat yeyunum mucosa. Normal and vagal denervated animals were used. Results indicate that there are no significant enzymatical changes after vagal extirpation.


Presence of urea in rat brain.

This paper reports the presence of urea in rat brain and the evidence that it does not come from blood contamination. The amount of urea is higher during the first 4 days after birth, and it decreases thereon as the brain develops. Urea concentration in brain remains constant from the age of 9 days to 1 year. A possible mechanism of brain urea formation is discussed.


[L-alanine: 2-ketoglutarate aminotransferase from maize embryo with complex kinetic properties for l-alanine (author's transl)].

The activity of L-Alanine: 2-oxoglutarate aminotransferase (E.C. 2.6.1.2) has been studied in maize (Zea mays) embryo. Crude extracts were fractioned with ammoniun sulfate to obtain low activity preparations of other aminotransferases present in crude extracts. The enzyme shows normal hyperbolic saturation curves for the substrasts: Pyruvate (Km 1 mM), 2-oxoglutarate (Km 0.4 mM) and L-Glutamate (Km 0.07 mM). However, it shows complex kinetics properties for the substrate L-Alanine, giving sigmoid saturation curves for L-Alanine at low but not at high fixed 2-oxoglutarate concentrations. These last results point to a regulation of the of L-Alanine degradation, which takes place during the germination of maize. Together with L-Glutamate and L-Alanine, the enzyme only seems to use L-Serine and L-Cysteine and their cetoacids.


[Effect of a beta-adrenergic blocking agent on erythropoietin production in the mouse (author's transl)].

The effects of the beta-adrenergic blocking agent (propranolol) on erythropoietin production in carbon monoxide intoxicated mice were studied. The raise in plasma erythropoietin after a 4 hour intoxication with carbon monoxide was 47% less in the propranolol treated group. A decrease of 65% in the endogenous erythropoietic response after 75 minutes of carbon monoxide intoxication was found in policithemic treated mice, as against the untreated ones. The tissue oxygen tension was reduced in the propranolol treated group. No changes was found in the hemoglobin oxygen affinity.


Protection by GABA and succinic semialdehyde of seed germination and some enzymatic activities against high concentration of hydroxylamine.

Hydroxylamine was found to stimulate germination of Lupinus albus at concentrations inferior to 10 mM and to inhibit it greatly at 20 mM concentration. This inhibition was partially restored by GABA or succinic semialdehyde. Hydroxylamine, at high concentrations, behaved as inhibitor in vivo on GABA 2-oxyglutarate amino-transferase and succinic semialdehyde dehydrogenase NAD-dependent, whereas it behaved as activator on succinic semialdehyde dehydrogenase NADP-dependent. No effects were observed on the enzymatic activities and the inhibited germination was partially restored, after GABA and succinic semialdehyde had been added to a growth medium with a 20 mM hydroxylamine concentration. A possible protection mechanism of GABA and succinic semialdehyde against hydroxylamine action is discussed.


[Determination of lecithin: cholesterol acyltransferase activity by a radioisotopic assay (author's transl)].

A method for determining Lecithin: Cholesterol Acyltransferase (LCAT) activity is presented. Trace amounts of labelled cholesterol are added to innactivated homologous substrate from a pool of normal serum. LCAT activity is determined measuring the cholesterol esterification, and is expressed as micrograms of cholesterol esters formed per milliliter plasma per hour. LCAT time-course, reproducibility, activity after serum storage at 4 degrees C, and normal values from 20 healthy subjects are studied.


Effect of insulin on plasma triglyceride concentration in hepatectomized geese.

The effect of insulin on the removal of plasma triglycerides was tested in hepatectomized geese. In this preparation plasma triglyceride concentration decreases exponentially following hepatectomy. Infusion of insulin (0.001 U/kg/min. for 60 minutes) had no significant effect on the rate of disappearance of plasma triglycerides in the hepatectomized animals. The conclusion is, therefore, reached that insulin does not affect the removal of plasma triglycerides by the extrahepatic tissues in the goose.


Imipramine enhancement of pentobarbital toxicity in rats.

The toxicity of pentobarbital was examined in male Wistar rats pretreated with a non-toxic dose of imipramine (10 mg/kg, po). Pentobarbital (70 mg/kg, ip) lethality was enhanced up to 6 hr after imipramine administration, and pentobarbital (45 mg/kg, ip) sleeping time was prolonged up to 12 hr after imipramine. Physiological measurements showed that imipramine pretreatment 2 hr prior to pentobarbital (70 mg/kg, ip) enhanced barbiturate depression in mean blood pressure, oxygen consumption and respiration rate, but not in heart rate or back skin temperature. Analysis of brain radioactivity after [14C] pentobarbital indicated that these effects of imipramine were not solely the result of inhibition of liver metabolism.


Fenfluramine-induced hyperthermia and stimulation in the rabbit.

Fenfluramine produces dose-related hyperthermia and behavioral stimulation in rabbits following intravenous administration. Both responses were antagonized by pretreatment with cinanserin, cyproheptadine, or fluxetine. Methergoline likewise abolished the stimulatory effect of fenfluramine and produced a partial blockade of the hyperthermia. Haloperidol was ineffective as a fenfluramine antagonist. This study demonstrates that fenfluramine-induced hyperthermia and stimulation in the rabbit result from an indirect action upon serotonergic receptors.


Myocardial function during hypoxia in the presence of different buffers.

Electrically driven rabbit left atria were exposed to 20 min periods of either hypoxia or anoxia in the presence of a bicarbonate-phosphate buffer, a Tris buffer [tris (hydroxymethyl) aminomethane hydrochloride] or combination of both. The bicarbonate-phosphate buffer system was shown to be important for tissue survival during hypoxia or anoxia whereas recovery was diminished in the presence of Tris only. Stimulus threshold and arrhythmias were shown to increase for atria in Tris. Oxygen consumption determinations on both spontaneously beating right atria and quiescent left atria showed no difference between pre- and post-hypoxia or between different buffers. Tris was shown to elicit a positive inotropic effect without an increase in O2 consumption.


Absorption and first-pass metabolism of 14C-gamma-hydroxybutyric acid.

The recovery of radioactivity from plasma, urine and feces was determined in rats after administration of oral and intravenous doses (200 mg/kg) of 14C-labeled sodium gamma-hydroxybutyric acid. Very small portions of the radioactive dose were recovered in the urine (5.5%, oral; 7.1%, intravenous) and feces (1.5% oral; 0.6%, intravenous) collected between 0-48 hours after drug administration. Considerable levels of radioactivity were found in the plasma after oral dosing. The area under the plasma radioactivity time curve after an oral dose was found to be 65% of that observed after an equivalent intravenous dose. This value is much larger than the relative area value (8%) calculated on the basis of free gamma-hydroxybutyric acid. Results of this study strongly indicate that first-pass metabolism, rather than lack of absorption, is responsible for the apparently poor oral bioavailability of gamma-hydroxybutyric acid.


Metabolism of 2,5-diphenyloxazole (PPO) by trout liver microsomal mixed function monooxygenase.

Metabolism of 2,5-diphenyloxazole (PPO) has been characterized in trout liver microsomes. Trout liver microsomes have been found to metabolize PPO into at least one NaOH extractable flourescing metabolite having a strong excitation peak at 345 nm and an emission peak at about 510 nm. As the metabolite(s) has (have) not been characterized, Vmax has not been determined, however in arbitary fluorescent units (FU) Vmax is several fold higher in the trout than in the male rat hepatic microsomes. Km is 12.7 M, being about twice as high as reported for mouse (Cantrell et al. 1975). Optimum assay conditions have been established for the metabolism of PPO by trout liver microsomes. NADPH generating system is essential and the metabolism was strongly inhibited by alpha-naphthoflavone, but much less markedly by SKF 525 A or metyrapone.


Inhalation of tobacco and marijuana in dog over a period of 30 months: effect on body weight, food intake and organ weight.

The measures of body weight and food intake in marijuana or tobacco smoking dogs and a non-smoking control group show no significant change after 27 months of inhalation; except a slowing of weight gain during 9 months, in spite of increased food consumption at 3 months. During this period, the tobacco smokers ate much less and at the 9 th month only a significant slowing in weight gain was noted. At the end of the experiment, the organ weight/total weight ratio of these 3 groupes of dogs presented no significant difference.


Benzene and lead inhibition of rabbit reticulocyte heme and protein synthesis: evidence for additive toxicity of these two components of commercial gasoline.

Both benzene and lead are known hematopoietic toxins. These compounds are components of commercial gasoline, and therefore pose an environmental risk. The present study demonstrates that benzene and lead individually inhibit both intact reticulocyte heme and protein synthesis in the presence or absence of iron-transferrin. When these two compounds are present in the same incubation, their effects are additive. These in vitro results suggest that further evaluation of the combined risks of benzene and lead is indicated. Furthermore, the data shows the potential for additive interaction by chemically unrelated environmental compounds.


Theophylline radioimmunoassay: synthesis of antigen and characterization of antiserum.

Antisera to theophylline (T) have been obtained by immunizing rabbits with a conjugate of 8-(3-carboxypropyl)-1,3-dimethylxanthine and bovine serum albumin. Comparison of 50% displacement values indicated good selectivity for T vs. a number of other xanthine derivatives. An analytical procedure using this antiserum can measure 200 pg of T and direct analysis of 0.1 mug/ml in plasma or 0.02 mug/ml in saliva is feasible.


In vitro testing of surface thrombogenicity using the thrombelastograph.

Synthetic surfaces can be assessed for their ability to promote or inhibit whole blood coagulation with improved accuracy using a new protocol developed for the Thrombelastograph instrument. Results obtained from the analysis of the hydrodynamic state of blood clotting in Thrombelastograph chambers have enabled a quantitative interpretation of the output of this instrument to be made. The thrombogenic properties of a segmented polyurethane and a polydimethyl siloxane are compared with a preparation of reconstituted elastin. It is seen that a four-fold delay in clotting time is exhibited by reconstituted elastin when it is compared with other biomedical synthetic materials tested.


Drug induction and experimental cholestasis.

The occlusion of bile duct reduced the microsomal cytochrome P-450 activity in the liver of rats. However, the effects of the inducer drug, phenobarbital, were not abolished.


Studies concerning the hypercholesterolemia of pregnancy: cholesterol catabolism and excretion during late pregnancy in the rat.

To investigate the mechanism of hypercholesterolemia noted in pregnancy, cholesterol catabolism and excretion was investigated during late pregnancy in the rat. Pregnancy was associated with an increase in plasma cholesterol and a decrease in the concentration of both cholesterol and bile acids in bile (with no difference in bile flows). The appearance of injected 4-C14-cholesterol in the bile of pregnant females was less than that of virgin females with a significant decrease in the bile acid fraction. The cholic/chenodeoxycholic acid ratio of newly formed C14 bile acids in pregnant rat bile was lower than in the bile of virgin female rats. Surprisingly, cholesterol balance studies failed to reveal any difference in the fecal excretion of neutral sterols or bile acids between virgin and pregnant female rats. The hypercholesterolemia of pregnancy could be partially due to the decrease in biliary cholesterol and bile acid excretion. The lack of difference in fecal cholesterol excretion is perhaps due to the operation of compensatory absorption mechanisms in the intestine which needs further investigation.


Demethylation in rats chronically treated with cocaine.

Norcocaine was prepared from cocaine utilizing diethyl azodicarboxylate. The rate of demethylation of 14C-cocaine in rats receiving either chronic or acute dosages of the drug was investigated. No significant difference in the rate of 14CO2 exhalation from the two groups was observed.


Effect of anti-inflammatory drugs on lipase in vitro.

Mefenamic acid, and to a lesser extent, flufenamic acid have a significant inhibitory effect on lipolysis as determined by the action of mouse pancreas lipase on the dilauric (didodecanoic) acid ester of fluorescein. Ibuprofen, fenoprofen calcium, phenylbutazone, oxyphenbutazone and alclofenac had comparatively little effect.


Cardiovascular toxicity of dihydroxytryptamines.

A comparison of the acute toxicity and a histological examination of the toxic effects in mouse of 4,7-; 5,6-; 5,7- and 6,7-dihydroxytryptamines and related compounds are present. A time and dose dependent induction of subepicardial lesions by 5,6-dihydroxytryptamine is demonstrated. The development of ischemic necrosis of the vaculature of the tail following 6,7-dihydroxytryptamine is described. The toxic effects of these tryptamines are discussed with regard to the phenomena of specific neurodegeneration induced by 5,6- and 5,7-dihydroxytryptamines.


Penetration of phenylacetic acid across the blood-cerebrospinal fluid barrier.

Labeled phenylacetic acid (14C-PAA) penetrates blood-cerebrospinal fluid (CSF) barrier in cats only under a high gradient of concentration; under these conditions the administration of large doses of either PAA or probenecid decreases the plasma:CSF 14C-PAA ratio. 14C-PAA is quickly removed from the CSF and blood and is excreted into urine; this excretion is blocked by probenecid. It appears, therefore, that PAA crosses the blood-CSF barrier with difficulty and that is secreted by the kidney.


Effect of an adenosine deaminase inhibitor on the uptake and metabolism of arabinosyl adenine (Vidarabine) by intact human erythrocytes.

Tritium-labeled vidarabine was incubated with fresh citrated human blood in the absence and presence of an adenosine deaminase inhibitor, co-vidarabine was rapidly deaminated to form ara-Hx with minimal incorporation into the erythrocytes. Ara-HxMP was identified as the major component in the erythrocytic nucleotide pool, together with small amounts of IMP, adenosine nucleotides and traces of arabinosyl nucleotides. Addition of the inhibitor completely protected vidarabine from enzymatic deamination and resulted in much greater accumulation of vidarabine 5'-mono-, di-, and triphosphates in the erythrocytes.


Long-retained metabolites of delta9- and delta8-tetrahydrocannabinols identified as novel fatty acid conjugates.

Long-retained metabolites of delta9-tetrahydrocannabinol (delta9-THC) and delta8-tetrahydrocannabinol (delta8-THC) previously detected in the liver, spleen, fat, and bone marrow of the rat after I.V. or I.P. injections of 14C-delta8-THC or 14C-delta9-THC, have been identified as fatty acid conjugates of 11-hydroxy-delta9-THC and 11-hydroxy-delta8-THC. Characterization of the metabolites was facilitated by their large-scale in vitro production from 11-hydroxy-delta9-THC and 11-hydroxy-delta8-THC with a rat-liver microsomal enzyme system. Conjugation of long-chain fatty acids to drugs or their hydroxylated metabolites may have considerable biological significance.


Effect of isoproterenol on uptake of calcium-45 by pregnant human and rat myometrium.

Rat and human myometria contract is response to substitution of external Na+ with Li+. This contraction was accompanied by elevation of 45Ca uptake in rat but not human uterus. The lanthanum technique failed to demonstrate elevation of cellular 45Ca in human myometrium by Li+ substitution. It also failed to demonstrate reduction of Li-elevated 45Ca uptake by isoproterenol or drugs considered to inhibit calcium influx, in rat myometrium although these drugs prevented Li-induced contraction. In human myometrium, isoproterenol increased 45Ca uptake. This probably represents increased extracellular calcium binding. Isoproterenol relaxed depolarized human myometrium provided that the external calcium had been removed for 15 minutes.


Retardation of symptoms of dystrophy in genetically dystrophic chickens by chemotherapy.

Chickens homozygous for muscular dystrophy were treated twice-daily with the serotonin antagonist, methysergide. Development of the dystrophic state was monitored by a test of skeletal muscle weakness, and by the characteristic marked evaluation of creatine phosphokinase (CPK) in the serum. The drug treatment prevented the onset of muscle weakness for 45 days ex ovo in all of the test animals, and for more than 60 days in 80% of them, in contrast to the untreated dystrophic animals. The CPK elevation in serum was also markedly reduced in the treated animals. A serotonin-mediated vascular effect or a direct action of serotonin on the muscle, is suggested to be involved in the development of muscle weakness in this form of dystrophy, and to be an appropriate target for chemotherapeutic control.


CC14 administration to strain A/J mice or rats and the arachidonic acid content of their liver microsomal prospholipids.

CC14 administration of Sprague-Dawley male rats causes a significant decrease in the arachidonic acid content of their liver microsomal phospholipids. On the contrary, its administration to strain A/J male mice does not modify the concentration during periods of intoxication up to 24 hr. Since this strain of mice is more susceptible to CC14-induced injury than the rat, results indicate that lipid peroxidation can not be the key event in damage induced by this haloalkane.


Tolerance development to cadmium-induced alteration of drug action.

Cadmium administration potentiates the duration of hexobarbital-induced hypnosis and inhibits the rate of hepatic microsomal metabolism of this drug in the male rat. The threshold dose of cadmium required to produce these alterations in drug action is 0.84 mg Ck/kg. If subthreshold doses of cadmium (0.21 or 0.42 mg Cd/kg) are administered prior to the 0.84 mg Cd/kg dose, the cadmium-induced alterations in drug action are no longer observed.


Effects of chronic administration of delta9-tetrahydrocannabinol on the heart rate of mongrel dogs.

Chronic administration of delta9-tetrahydrocannabinol (delta9-THC) 1 mg/kg, s.c. twice a day for 7 days failed to produce any significant alterations in the peripheral autonomic transmission to the heart of mongrel dogs anesthetized with sodium pentobarbital. Prior to anesthesia, heart rate of the treated dogs was slightly greater than that of the placebo group. However, under pentobarbital anesthesia, heart rate of the delta9-THC treated animals was significantly lower than that of the placebo group. The data suggested that chronic delta9-THC may have an inhibitory effect on the central vagal structures and in addition, this agent antagonizes the ability of pentobarbital to elevate heart rate in dogs.


The importance of angiotensin II formation in the CNS in angiostensin I - elicited thirst.

The drinking response produced by direct injection of angiotensin I and II into the brain of the rat, was studied, using the angiotensin blocking agents SQ-20,881 (SQ) and P-113 (Saralasin). SQ inhibits angiotensin converting enzyme, preventing formation of angiotensin II, while P-113 is an analogue and competitive inhibitor of angiotensin II. SQ blocked central angiotensin I drinking, but only when the enzyme inhibitor was injected into the ventricle. Angiotensin II induced thirst was not blocked by SQ. P-113 inhibited angiotensin I and II drinking responses in both the preoptic area of the hypothalamus and the lateral ventricle. These data indicate that conversion of angiotensin I to angiotensin II is important in angiotensin-induced drinking, although an independent action of angiotensin I on drinking can not be ruled out at this time.


Disenecioyl dehydroretronecine--synthesis and acute hepatic toxicity of a pyrrolizidine alkaloid pyrrole analog.

Disenecioyl dehydroretronecine (DSDR), a semi-synthetic analog of the highly reactive pyrrole metabolites of the pyrrolizidine alkaloids, has been synthesized from disenecioyl retronecine. Rats which received 40 mg DSDR/kg body weight via the mesenteric vein showed multiple depressed areas (less than 2 mm in diameter) on the surface of the median lobe of the liver. Microscopically these areas consisted of hepatic venous occlusion, necrosis, and proliferation of fibroblasts and bile ducts in and around the portal triad. These hepatic lesions were similar to those produced by dehydroretrorcine.


The distribution of halofenate in plasma: a comparative analysis using Scatchard vs. stepwise association constants.

The distribution of Halofenate between the free and albumin bound forms was calculated by the use of two computer programs using both Scatchard association constants for a 3,3,7 model, and six stepwise equilbrium constants over a range of drug concentrations reported in man. The calculations, using either set of constants, showed that only 0.3 to 0.5% of the drug would be free. Using Scatchard association constants, it was estimated that 92 to 95% of the drug would be bound by the high affinity set of sites, and lesser amounts by sites of lesser affinity. A more complex pattern of distribution was obtained with the stepwise equilibrium constants. At low concentrations of Halofenate the complex with one mole of drug/mole of protein was most abundant and at the highest concentration studied the complex with two moles of drug/mole of protein was most abundant.


Specificity of the digoxin radioimmunoassay with respect to dihydrodigoxin.

An investigation was conducted to determine the specificity of the digoxin antibody provided in a commercially available radioimmunoassay kit with respect to dihydrodigoxin. Over the concentration range of 0.5 to 8.0 ng./ml. dihydrodigoxin displaced the 125I digoxin derivative from the antibody to a degree that could be significant at clinically observed serum and urine digoxin concentrations.


Determination of ftorafur and 5-fluorouracil levels in plasma and urine.

A gas chromatographic method was developed for ftorafur (Ft) detection in plasma and urine with a sensitivity of 1 mug/ml. Specific determination of its metabolite 5-fluorouracil (FU) with a sensitivity of 1 ng/ml was achieved by column chromatographic separation from Ft and subsequent gas chromatography-mass spectrometry of bis-silyl-FU in the selected ion mode (GC-MS-SIM) using bis-15N-FU as internal standard. Intravenous injections of 2-14C-Ft and 2',5'-14C-Ft were given to rats and rabbits respectively, and plasma and urine were analyzed for Ft, and 14C activity. Unchanged Ft accounted for most of the 14C activity in plasma, while FU concentrations were below 0.15% and 0.4% relative to Ft concentrations in the rabbit and the rat, respectively. 30-60% of the urinary 14C activity was unchanged Ft and less than 0.2% FU. The significance or low FU levels is discussed in view of the hypothesis that Ft acts as a transport form of its metabolite FU.


Experimental infection of poultry with Salmonella infantis.

Six-month-old cockerels and point-of-lay pullets were infected orally with S infantis (1 X 10(10). The cockerels were slaughtered at intervals up to 42 days, and the pullets slaughtered 20 weeks, after infection. Infection produced no clinical disease and minimal changes were observed at autopsy. Serological responses were transient, frequently absent three to six weeks after infection, no response at all being recorded in some birds. Faecal excretion was observed most frequently during the early stages of infection. There was no evidence of egg transmission.


The presence of erythritol in the fetal fluids of fallow deer (Dama dama).

Gas liquid chromatography has been used to compare the levels of erythritol in fetal fluids from fallow deer with those in fetal fluids from cows and small laboratory animals. The relationship between the relatively high levels of erythritol found in allantoic and amniotic fluid from fallow deer and the possible susceptibility of this species to brucellosis is discussed. An interesting accessory finding was the high concentration of calcium phosphate in the allantoic fluid from these deer.


Role of pentose-phosphate pathway in haemolytic crisis of chronic copper toxicity of sheep.

Although the rise in blood copper is associated with onset of the acute haemolytic crisis of chronic copper poisoning in sheep, the sudden fall in erythrocyte glutathione is apparently not due to a direct action of the copper. Moreover the reduced glutathione of the red cells is converted to some form that is not capable of regeneration by the pentose-phosphate mechanism. Only negligible inhibition of the pentose-phosphate enzymes occurs. As the haemolysis proceeds, there is a rapid recovery of erythrocyte glutathione levels, and a marked increase in pentose-phosphate enzyme activity, consistent with influx of young red cells. It seems that the release of copper into blood from liver at the haemolytic crisis is associated with an increase of the oxidative state of the blood, possibly by simultaneous release of other components from the liver.


Pathogenicity of certain Mycoplasma species in the bovine mammary gland.

Strains of three of the species of mycoplasmas isolated from pneumonic calf lungs, Mycoplasma dispar, Mycoplasma bovirhinis and Acholeplasma laidlawii, were inoculated into the bovine mammary gland. Pathogenicity of the species was monitored by counting the inflammatory cells and mycoplasmas in milk. Six of the seven M dispar strains produced clinical mastitis, but the seventh strain, Vic12, was apparently avirulent. The four strains of M bovirhinis caused subclinical mastitis. None of the four strains of A laidlawii multiplied and they produced only a transient cell response in the milk.


Neuropathological changes associated with the neonatal maladjustment syndrome in the thoroughbred foal.

A neuropathological investigation was carried out on the brains of 18 foals suffering from the neonatal maladjustment syndrome and results were compared with those obtained from the brains of nine foals dying from other causes. Necrosis of the cerebral cortex of an ischaemic nature was found in nine of the neonatal maladjustment foals, frequently accompanied by local haemorrhage. In three of this group of foals there was also necrosis in the diencephalon and brain stem. In the brains of the nine other affected foals there was haemorrhage in the cerebrum and sometimes in the brain stem and cerebellum; in four animals there was also brain swelling or oedema. In the control gorup, significant haemorrhage in the brain was the only finding in two foals, one premature and one stillborn apart from minimal ischaemic damage in the latter. The nature of the CNS damage in the neonatal maladjustment syndrome is considered in the light of recent experimental evidence. Although the cause is unknown it may be related to circulatory disturbances induced in the foal at the time of birth.


Biological and ecological investigations on thiamineless dwarf-colony variants of Staphylococcus aureus of bovine udder origin.

Thiamineless dwarf-colony variants of Staphylococcus aureus (D strains) were compared with their homologous normal-colony variants and with normal S aureus. The majority of D strains tested in vitro exhibited biological features typical of S aureus. D strains, however, produced lower titres of alpha-haemolysin and this toxin was also produced by a smaller proportion of these strains. D strains and S aureus strains were equally susceptible to disinfectants used in dairy farming and were isolated with similar frequency from the skin of the udders of infected cows. Attempts at inducing and selecting D strains from normal S aureus by exposing the latter to antibiotics in vitro and in vivo have so far failed.


Studies on the pathogenicity of thiamineless dwarf-colony variants of Staphylococcus aureus isolated from the bovine udder.

The pathogenic characteristics of thiamineless dwarf-colony variants of Staphylococcus aureus (D strains) were compared with those of normal S aureus isolated from the bovine udder. Intravenous injection of D strains into embryonated hen's eggs and intracranial inoculations into mice produced similar results to those with normal S aureus. Intramammary infusion of D strains into normal cows resulted in mastitis which was indistinguishable from the type produced by infusion of S aureus. Intramuscular injection of thiamine HCl into cows with chronic mastitis due to D strains did not alter the course of the disease, although normal sized S aureus colonies were isolated several days after thiamine injection.