Malignant melanoma in Nigeria-pathological studies.

Pathological features of twenty-one cases of malignant melanoma studied in the University of Nigeria Teaching Hospital, Enugu during the period January, 1974 to December, 1975 are presented. Malignant melanoma accounted for 2.4% of all tumours and 4.5% of all malignant tumours, greatest age incidence being in the fifth to seventh decades. The male to female sex ratio was 2:1. 73.2% of cases were of the nodular variety. 81% melanomas occurred on the sole of feet validating the hypothesis that the pigmented skin in Africans is resistant to malignant melanoma. Melanoma in Nigerians would appear essentially to be arising from epidermal melanocytes and not from preexisting naevus cells. Hence we do not feel prophylactic removal of plantar moles as suggested by Onuigbo (1975) is desirable. Histologically, there was no clear association between the cell types and the kind of melanoma or invasion of the tumour. The difference in behaviour and natural history of malignant melanoma would appear to have a bearing on the local tissue and also general immune mechanisms of the host.


Case report. Subacute sclerosing panencephalitis (SSPE).

A case report of SSPE (Subacute Sclerosing pan encephalitis) is presented to demonstrate some of the characteristic clinical, pathological, electroencephalographic, and laboratory features of the disease.


Some helminthozoonotic infections in Zambia.

Parasitic infections constitute an important group of zoonoses. Stool examination of inpatients, medical examinees and out-patients in a sub-tropical environment established that Inermicapsifer madagascariensis and Schistosoma mattheei are occasionally anthropozoonotic in Zambia. Strongyloides fülleborni, a species normally parasitic in primates is not uncommon in man; whether it is anthropozoonotic or a parasite well adapted to man in this part of Africa needs further investigation. The finding of unidentified spiruroid ova was considered to be due to a spurious infection. The need for the differentiation of such organisms from those commonly infecting man is emphasized especially since the literature on such a subject is so sparse in the country and on the continent.


Analysis of 1089 cases of head injury.

1089 patients treated for head injuries at the Unversity of Nigeria Teaching Hospital, Enugu, are analysed. Seventy-two percent of them were males. The age group 20-30 years was most vulnerable, accounting for 32% of the total. Road traffic accidents were responsible for a staggering 80% of the total. Most of the children in this group were pedestrians hit by vehicles on the roads. About 42% of the head injuries were complicated, but the incidence of intracranial haematoma was only 1.3%. The mortality rate was 9% and most of the deaths (83%) occurred few hours after the accident. Road traffic accident was responsible for 97% of the deaths. Bronchopneumonea and brain oedema was the cause of death in 70.6% of the inpatient deaths from head injury.


Road traffic accidents: the doctor's point of view.

One-hundred and thirty-five road traffic accident admissions (38.8% of all accidents analysed) were studied with respect to their age, sex, and distribution of injuries. It was found that the adolescent and young adult males were mostly affected. The bed utilization rate in the wards where these accident victims were admitted was found to be lower than for other wards. Ways by which the services in hospitals--both specialist and general--can be organized for a more economic and efficient care of road traffic accident casualties are discussed.


Infantile cortical hyperostosis (Caffey's disease).

A case of infantile cortical hyperostosis (Caffey's disease) is presented with its usual clinical and radiological manifestations. The accompanying anaemia and thrombocytopenia as seen in our case is discussed. The possibility of autoantibodies secondary to an immunological defect is put forward to explain the cause of the anaemia and thrombocytopenia. This may be a new feature of the disease or a modification of the current concept.


Variations in the soluble alpha-crystallin proteins from human cataractous lenses.

Human cataractous lenses from subjects aged 20-91 years were extracted in tris/glycine buffer and fractionated on Sephadex G-75 column. Four fractions, F1, F2, F3 and F4 identified as alpha-, beta1-, beta2- and gamma-crystallin were obtained. Gel electrophoresis of alpha-crystallin in polyacrylamide containing 6M urea revealed changes in polypeptide composition, colouration; variation in band pattern and mean mobility. The relative mobilities of the protein bands were used to calculate coefficient of similarity within the same age group and among different age groups.


Histopathological studies of carcinoma of cervix uteri in Ibadan.

Carcinoma of the cervix is by far the commonest gynecologic malignancy in Ibadan. In a histopathologic study of the disease, 93.9% of all the cases were found to be of the squamous cell carcinoma variety while 6.1% were of the adenocarcinoma group. It was found that most patients with the well differentiated squamous cell carcinoma were above the age of 45 years in contrast to the undifferentiated carcinoma. Even though the difference was not statistically significant, it was speculated that cervical cancer manifesting itself before the age of 45 years may be more aggressive than that occurring in older women. Similarly, it was shown that increasing age, more frequent marriages and parity may augment the possibilities, at least in the negro population, of a woman developing adenocarcinoma of the cervix.


Diagnosis of extracerebral fluid collections by computed tomography.

The computed tomography scans of 90 patients with extracerebral fluid collections were reviewed. Epidural hematomas, acute, subacute, and chronic subdural hematomas, convexity subarachnoid hemorrhages, subdural hygromas, and one epidural empyema were seen. The CT findings were analyzed and correlated with the time elapsed since injury (when known) and the results of radionuclide scans (when available). The overall accuracy of CT in detecting extracerebral fluid was 90% with no acute hemorrhages missed. In subacute and chronic subdural collections, six CT scans were false negative in whole or in part. Three false positive interpretations were made and are discussed.


Computed tomography in ocular neoplastic disease.

The computed tomographic findings of four patients with neoplastic disease of the global rim are discussed. All four patients demonstrated eccentric thickening of the scleraluveal rim with extension into the globe. Possible ways of differentiating these lesions from other orbital conditions are discussed. Window widths below 100 EMI units are best to visualize neoplasms of the global rim. For evaluation of the orbits, multiple window widths with varying window levels should be used.


External anatomic landmarks of the abdomen related to vertebral segments: applications in cross-sectional imaging.

Palpable external anatomic landmarks including the xyphoid tip, ends of the eleventh ribs, umbilicus, iliac crests, anterior superior iliac spines, and symphysis pubis were studied in relation to vertebral segments posterior to these landmarks. Results of CT and ultrasound studies, localized according to external abdominal landmarks, can thus be correlated with other radiologic studies in which abnormalities are localized by vertebral level.


Buckling of the innominate artery simulating a right apical lung mass.

A tortuous retroflexed innominate artery can simulate a right apical mass. Four cases are presented to illustrate the four fairly distinct appearances which can result. When the innominate artery buckles posteriorly and laterally, it occasionally impresses deeply into the lung and becomes almost completely surrounded by air. The artery will then look like a pulmonary mass on frontal radiographs. The lower margin of the mass is always more crisply defined than the upper margin, and the appearance on the lateral film is fairly characteristic. Aortography is recommended when the radiographic picture is equivocal. In a survey of 200 randomly selected patients over 50 years old, only one had an innominate artery that presented as an apparent pulmonary mass.


External iliac artery fibrodysplasia.

Clinical and arteriographic features of 12 patients with external iliac artery fibrodysplasia are reviewed. These lesions usually occur in patients having arterial fibrodysplasia elsewhere, attesting to the fact that they represent a generalized arteriopathy. Occasionally they occur in association with severe atherosclerosis. External iliac artery fibrodysplasia exhibits the classic corrugated "string-of-beads" angiographic appearance in the majority of patients. The pattern of aneurysmal dilatation of the external iliac arteries in one patient and the aorta and common iliac and internal iliac arteries in another with diffuse arterial fibrodysplasia has not been previously reported. Three patients had symptoms directly referable to external iliac artery fibrodysplasia. The lesions may be symptomatic when the arterial lumen is sufficiently compromised to reduce blood flow or when superimposed thrombosis and/or embolization occurs.


Comparison of arachnoiditis produced by meglumine iocarmate and metrizamide myelography in an animal model.

Myelography in monkeys was performed with either meglumine iocarmate or metrizamide. The severity of resultant arachnoiditis in each animal 12 weeks later was evaluated by repeat myelography and by histologic study of the arachnoid. Three of the four animals examined with meglumine iocarmate had severe arachnoiditis; none of the four animals examined with metrizamide had as severe changes. The difference between the two groups was statistically significant (P less than .05).


Proximal tibiofibular joint: anatomic-pathologic-radiographic correlation.

An anatomic-pathologic-radiographic study of the proximal tibiofibular joint was undertaken. This synovial articulation between the proximal tibia and fibula may communicate with the knee joint in 10% of adults. Radiography of the normal proximal tibiofibular articulation outlines a consistent relationship between the proximal portions of the tibia and fibula. Disruption of this normal relationship is indicative of anterolateral or posteromedial subluxation or dislocation. Articular disorders of this joint include reheumatoid arthritis and septic arthritis. In the latter, initial alterations of the knee joint may subsequently extend to involve the proximal tibiofibular joint, illustrating the potential communication between these two articulations.


Gastrointestinal angiographic findings in systemic amyloidosis.

Amyloidosis is a multisystem disease process of unknown cause in which characteristically staining protein-polysaccharide material is deposited in body tissues. Although gastrointestinal involvement is usually asymptomatic, amyloid infiltration of mesenteric and submucosal vessel walls may be associated with acute or recurrent gastrointestinal hemorrhage in patients with the diagnosis of amyloidosis. Angiography in such cases may demonstrate arterial and venous changes as a result of these vascular wall deposits. Two patients with proven amyloidosis and gastrointestinal hemorrhage are presented, and their angiographic findings are discussed with the pathologic correlations.


Atypical appearances of benign hyperplastic gastric polyps.

The vast majority of epithelial polyps of the stomach can be divided into two groups: (1) hyperplastic or regenerative polyps, and (2) adenomas. Of the two, hyperplastic polyps are much more common; they are nonneoplastic lesions which are typically asymptomatic, small, smooth-surfaced, and often multiple. Malignant transformation virtually never occurs in this group of polyps. Adenomas are true neoplasms; they are relatively large, have an irregular surface, and show a distinct tendency to undergo malignant transformation. In this paper the radiologic appearances of hyperplastic gastric polyps, with special reference to atypical findings, are discussed and illustrated. It is shown that simple hyperplastic polyps may present any or all of the radiologic criteria suggestive of gastric adenomas or even frank malignancy. Thus, while radiology plays a vital role in the initial detection and followup of gastric polyps, optimum clinical management of the patient is best based on knowledge of the histologic structure of the lesion obtained by endoscopy and biopsy.


Observations on the medical efficacy of computed tomography of the chest and abdomen.

In a retrospective study of 687 computed tomographic (CT) examinations of the chest and abdomen performed over a 1 year period, 16% of the examinations produced information not otherwise available which altered patient diagnosis, prognosis, or therapy. Sixteen thoracotomies and 18 laparotomies were avoided as a result of information available only from CT examinations. CT was of particular value in the evaluation of mediastinal masses, in the assessment of suspected or proven lung cancer, and in the evaluation of pleural and extrapleural masses. It was of notable clinical value in evaluating patients with intraabdominal abscesses, pancreatic disease, staging of malignancies for radiation therapy and surgery, and excluding the presence of suspected masses.


Ectopic pregnancy: criteria and accuracy of ultrasonic diagnosis.

Of 26 ectopic pregnancies, a correct positive ultrasonic diagnosis was made in 77%, while a false negative diagnosis was made in 23%. Most commonly, the ectopic pregnancy appeared as a complex adnexal mass immediately adjacent to an enlarged "empty" uterus. Ultrasonic identification of an extrauterine gestational sac, allowing a definitive diagnosis of ectopic pregnancy, was uncommon.


American College of Radiology Diagnostic Efficacy Studies.

Questions about costs and benefits of radiologic diagnostic methods have lead to the formation of a standing American College of Radiology Committee on Efficacy. In the past several years this committee has defined a hierarchy of efficacies associated with radiographic procedures and developed methods for assigning a numerical value to diagnostic efficacy. A national study of common x-ray examinations in the emergency setting has been conducted. These studies suggest that diagnostic thinking of clinicians was influenced by the results of the x-ray procedures they requested in more than 92% of cases. Medicolegal consideration were a prime concern of the clinician only 6% of the time overall when selecting the most frequent radiologic procedures conducted in hospitals. Considerable uncertainty about clinical diagnoses was typically present at the time radiologic examinations were requested; three-fourths of the time the most important diagnosis under consideration was judged to be less likely after x-ray examination than before. About one-eighth of the time the radiographic information focused attention on a new "most important" diagnosis. The committee plans further studies to include other imaging modalities and practive settings.


Computed body tomography in children: evaluation of 45 patients.

Computed tomographic (CT) body scans from a series of 45 infants and children were reviewed for the indications leading to the examinations, for technical quality of the images, and for diagnostic value of CT scanning. Useful diagnostic information was obtained in 30 of the 39 cases with technically satisfactory images. Individual case reports of CT examinations including findings from other imaging studies demonstrate how CT can interface with other methods to yield additional diagnostic information. Methods of patient preparation and suggested indications for CT body scan examinations of children are presented.


Cranial computed tomography in diagnosis and management of acute head trauma.

Review of the computed tomographic findings in 286 patients with acute craniocerebral trauma revealed several types of lesions: hemorrhagic contusion, intracerebral and extracerebral hematomas, general and focal cerebral swelling, and shearing injury of the cerebral white matter. Hemorrhagic contusions are the most frequent lesion and may result in focal neurologic deficits. General cerebral swelling occurs frequently in children and necessitates prompt medical management for complete recovery. Mortality rates for intracerebral, subdural, and epidural hematomas were lower for this series than for series that preceded computed tomography. Because of the availability of computed tomography, there was an 84% reduction in arteriography, 58% reduction in surgical intervention, and a 24% reduction in skull radiography.


Computed tomography in patients with cerebrovascular disease: impact of a new technology on patient care.

The medical care of 157 patients with suspected cerebrovascular disease was analyzed to assess the impact of the new technology, computed tomography (CT) of the brain, on the care of these patients. A cohort of patients admitted before installation of CT was compared to two cohorts admitted after installation of CT. Length of hospital stay, speed of diagnostic workup, treatment, and discharge plans were not significantly different. Discharge diagnoses were more specific after installation of CT. Lumbar punctures and radionuclide brain scans were used less frequently, but utilization of other diagnostic studies was unchanged. Aggregate charges for diagnostic procedures actually increased in both after-CT groups. In this study, addition of CT to the neurodiagnostic armamentarium resulted in little demonstrable improvement in the care of these patients with cerebrovascular disease but did increase the cost of evaluation. This is unlike the situation for patients with brain tumors, where CT was shown to improve care while not increasing cost. These results may help guide the use of CT by physicians caring for patients with cerebrovascular disease and suggest that health planners not use all patients with cerebrovascular disease in estimating need for CT.


Impact of computed tomography on the care of patients with suspected hydrocephalus.

To assess the impact of computed tomography (CT) on patient care, a cohort of patients with suspected hydrocephalus admitted before installation of CT was compared to a similar cohort admitted after installation of CT. The after CT cohort used significantly fewer pneumoencephalograms and radionuclide brain scans. The average cost of neurodiagnostic evaluation was 22% less after CT. However, speed of workup, therapy, institution of therapy, discharge plans, and discharge diagnoses were not different for the two cohorts. We conclude that CT has made the diagnostic evaluation of patients who otherwise would have required pneumoencephalography for suspected hydrocephalus less expensive and less hazardous.


Efficacy of computed tomography of the head in changing patient care and health costs: a retrospective study.

Detailed analysis of all neurologic and neurosurgical admissions at Johns Hopkins Hospital for 6 months prior to the second 6 months after installation of a CT head scanner was undertaken in an attempt to identify the effect CT had on health care decisions, costs, and morbidity. Data showed decreased cost of more than $2,000 per patient and shorter length of stay by 7 days in patients with extracerebral collections, and more than $2,500 and 8 days reduction in patients with tumors after CT was in use. A group matched by computer for age, diagnosis, and physician showed decreased costs of more than $2,000 and shortened stay by more than 3 days per hospitalization. Increased costs were shown in patients with cerebrovascular disease after CT. Change in method of workup with fewer invasive studies for all patients (P less than .001) and significant increases in cost of diagnostic workup were demonstrated (P less than .001). There was no change in morbidity and mortality between the two groups. These data suggest that CT of the head may reduce cost and length of hospitalization in certain patient groups and frequently alters patient workup.


Clinical efficacy of computed body tomography.

A method for assessing the effect of computed body tomography on diagnostic understanding and therapeutic decision making is described and the results in the first 184 patients are presented. The patients' referring physicians provided the primary data used for the evaluation. CT improved diagnostic understanding in 41% of patients, reassured the physician about previously planned therapy in 43%, contributed to a change in therapy in 17%, and improved precision of previously planned treatment in an additional 10%. CT contributed to a decision not to perform surgery in 21% of patients in whom an operation had been provisionally planned While CT can play an important role in patient management, its measured value depends on the clinical problems investigated and the level of efficacy on which it is judged.


Comparison of computed and conventional whole lung tomography in detecting pulmonary nodules: a prospective radiologic-pathologic study.

Whole lung computed tomography (CT) was performed on 25 patients with clinical diagnoses including osteogenic sarcoma. Ewing's sarcoma, rhabdomyosarcoma, fibrosarcoma, and melanoma in whom conventional tomography had revealed from one to four parenchymal nodules in one lung deemed resectable for either staging or treatment purposes. Thoracotomy was performed within 3 weeks after conventional and computed whole lung tomography. All palpable nodules were resected, measured at the time of surgery, mapped by anatomic segment, and submitted for individual histologic evaluation. CT defined more nodules than conventional tomography in 48% of cases. The additional nodules were usually pleural or subpleural and 3--6 mn in diameter. CT identified 78% of all resected nodules greater than 3 mm in diameter, compared to 59% using conventional tomography. CT was also of value in detecting bilateral nodules earlier than conventional tomography and in documenting small nodule growth on successive examination. However, 60% of the additional nodules defined by CT and resected proved to be benign granulomas and pleural-based nodes at thoracotomy.


Computed tomography of musculoskeletal disorders.

The utility of computed tomography (CT) in evaluation of musculoskeletal disorders was assessed in 55 selected patients. CT provided unique information leading to a correct diagnosis in 45% of cases. In 78% the extent of a lesion was more clearly defined than on conventional imaging procedures, and in the same percentage the CT findings were used to plan optimal therapy. CT was most useful in demonstrating absence of a suspected mass lesion and in defining the full extent of a lesion involving the soft tissues.


Value of computed tomography in radiotherapy of lung cancer.

The effectiveness of CT scanning in radiotherapeutic treatment planning was evaluated in 32 patients with bronchogenic carcinoma. CT of the chest in pretreatment evaluation of these patients supplemented conventional clinical and radiographic patients supplemented conventional clinical and radiographic studies, resulting in (1) more clear delineation of tumor extent in 24 patients (75%); (2) change in assessment of the size of lesions in 14 patients (43%); (3) change of disease stage in 13 (40%); (4) demonstration of inadequacy of treatment plan in nine (28%); and (5) changes in the volume of normal tissue irradiated in 14 (40%). CT scan data was judged essential for treatment planning in 17 patients studied (53%). Unsuspected areas of tumor involvement were seen in 21 patients (65%). Use of the CT scan as a patient contour for radiotherapy treatment planning of lung cancer and alternative techniques are discussed.


Contribution of computed tomography to the treatment of lymphomas.

The effectiveness of computed body tomography (CT) in the workup, treatment planning, and follow-up of 38 patients with Hodgkin's disease and 59 with non-Hodgkin's lymphoma was analyzed. CT scanning can frequently define lymphoma in the retroperitoneum, and occasionally in mesenteric lymph nodes, spleen, and liver. These data are useful for staging, for radiotherapy treatment planning, and in monitoring response to radiotherapy or chemotherapy. CT was found to be particularly useful in patients with large mediastinal masses. Analysis of patterns of intrathoracic spread allowed modification of treatment techniques in 60% of patients with spread along the chest wall, in order to reduce the volume of normal tissue irradiated, while obtaining adequate dose distributions within the tumor volume. It is anticipated that chest CT scanning in lymphoma patients will lead to improved tumor control and reduction of radiation complications.


Efficacy of CT-assisted two dimensional treatment planning: analysis of 45 patients.

A method is presented for quantitatively assessing the impact of CT assistance in treatment planning for radiation therapy. A three-phased analysis of treatment plans for 45 patients was undertaken. Nonuniformity and local efficiency of dose delivered were compared without and with the utilization of CT information. Good agreement between the objective assessment of treatment plans and independent subjective optimization of the plans by a radiotherapist support the validity of this technique. On the basis of nonuniformity of dose, 31 of the 45 cases were planned more poorly in the absence of CT information. The addition of CT information permitted optimization by the physician in 25 of the 45 patients. Twenty-three of these showed improved local efficiency (92%). This study indicates that measurable improvements in treatment plans are available by taking advantage of CT information. These were greatest in the brain, lung, and retroperitoneum in this small group of patients.


Computed tomography: cost and efficacy implications.

Because CT is unique, it has been accepted by physicians with unrestrained enthusiasm. However, the capital investment and cost of maintenance are high, and there has been no orderly program of dispersion despite the profound interest of the regulatory agencies in cost containment. Although the diagnostic accuracy of CT in both the head and body is high, its information gain over other competing imaging methods, particularly those in the abdomen (ultrasound, nuclear medicine), has not been fully documented. In evaluating the cost effectiveness of CT, long-term outcome, while the most important criterion, requires carefully controlled studies over many years. Short-term value may be measured by assessing the degree to which CT furnishes new diagnostic information, its accuracy, its effect on the morbidity and mortality of diagnostic and theraupeutic procedures, its impact on treatment planning, and changes in cost and saving incident to its use. Prospective studies must relate the contribution of CT to that of competing methods and document the impact of additional diagnostic information.


Efficiency of utilization of a computed tomography scanner.

Efficient utilization of diagnostically effective but expensive computed tomography (CT) brain scanners requires understanding of time factors influencing patient throughput. In a study at UCLA Medical Center using an EMI Mark I brain scanner, the average number of patients studied was 16.3 per 15.5 hr workday, for an average of 52.7 min per patient. Of the patients, 51.5% were inpatients at UCLA, 45% received intravenous iodinated constrast infusion, and 33% had studies showing significant abnormalities. The x-ray tube was on 51.1% of the time the scanner facility was open, with scanning averaging 34.6 min per patient. The average number of images obtained was 10.4 per patient at 3.4 min per image. Patient handling, including contrast infusion, accounted for an additional 16.2 min per patient or 34.4% of the total time utilization. Anesthesia lengthened the procedure by 1 hr but was needed in only 4.5% of the cases. Flexible scheduling was essential, since 14% of the patients failed to keep their appointments or had their studies cancelled. These timing data suggest that the faster, more expensive CT scanners being introduced, while having diagnostic advantage for body scanning, will not significantly decrease cost per patient when used for brain scanning compared with the first generation machine studied.


Computed tomographic scanning in children: comparison of radiation dose and resolving power of commercial CT scanners.

Surface and internal radiation doses for abdominal computed tomography (CT) of children were determined using child-sized phantoms and seven models of CT body scanners. Resolving power of each scanner was determined simultaneously with the radiation dose determination. The average surface skin dose for a complete CT body examination ranged from 0.39 to 5.60 rad, varying with patient size and model of CT scanner employed. A high contrast (12%) resolving power phantom of water-filled holes in acrylic showed a range of 1.75--2.25 mm.


Fluoroscopically guided thin needle aspiration biopsy of the abdomen and retroperitoneum.

The results of 49 transabdominal and translumbar thin needle percutaneous aspiration biopsies in patients suspected of having malignant disease are reported. A correct diagnosis was obtained in 40 cases. Placement of the Chiba needle was accomplished by fluoroscopically controlled biplane radiography during constrast examinations. No complications were encountered. The technique allows cytologic diagnosis of malignancy without high risk exploratory surgery, prolonged hospitalization, or delay of treatment. Use of fluoroscopic needle guidance and biplane radiography for confirmation of position using various contrast examinations as markers is felt to be superior to either CT or ultrasound. The technique is readily available in all radiology departments.


Association of antral diaphragms and hypertrophic pyloric stenosis.

In a 2 year period at Children's Hospital of Philadelphia, seven human infants and a baby orangutan all presented with a previously unreported association of a prepyloric membrane and hypertrophic pyloric stenosis. In the humans, the pyloric stenosis was the obstructive lesion, and in the orangutan, the web. We also report a 6-year-old patient with previous pyloromyotomy who presented because of prolonged retention of a marble in the stomach by an associated antral membrane.


Double contrast barium enema in Crohn's disease and ulcerative colitis.

Double contrast barium enema examinations in 24 patients with Crohn's disease of the colon and 29 patients with ulcerative colitis were reviewed without knowledge of the clinical diagnosis. The radiologic diagnosis of Crohn's disease agreed with the clinical diagnosis in 98% of patients. In this condition the most common radiologic findings were discontinuous or asymmetric disease (88%) and discrete ulcers (67%) often on a normal mucosa. The latter are characteristic of early Crohn's disease and may enable the radiologist to be the first to suggest the diagnosis, particularly when both sigmoidoscopy and small bowel examination are normal. Of the patients with ulcerative colitis, a positive radiologic diagnosis was made in 83% on the basis of a granular mucosal pattern (79%) and continuous distal involvement (86%). The high accuracy of the double contrast technique, especially in Crohn's disease, and the relative specificity of the signs that it can demonstrate suggest that this is the preferred examination in the radiologic evaluation of inflammatory bowel disease.


Malignant fistulae of the gastrointestinal tract.

Internal malignant fistulae of the gastrointestinal tract involving two or more loops of different segments of the bowel are rare. The colon is frequently one of the participating loops. Observations on four such cases indicate that the fistulous tract connecting the two bowel loops is usually linear, somewhat wide, and does not produce significant approximation of the bowel loops involved. These radiographic features help to differentiate such fistulae from the benign type.


Air in gallbladder: a frequent finding in gallstone ileus.

A retrospective assessment of the presence of air in the biliary tract is presented, based on plain film findings in 16 proven cases of gallstone ileus. In addition to five cases that demonstrated air in the biliary radicles, four cases exhibited air exclusively in the gallbladder and duodenal bulb. A clearly identifiable radiographic appearance composed of two adjacent small air-fluid levels in the right upper quadrant is described. This radiographic feature represents the air- and fluid-filled duodenal cap adjacent to the visualized shrunken gallbladder. Recognition of this combination of findings helps in establishing a prompt preoperative diagnosis in cases of gallstone ileus.


Gallstones: in vitro comparison of physical, radiographic, and ultrasonic characteristics.

An in vitro study of 30 gallstones was undertaken in which radiographic, ultrasonic, and physical characteristics were compared. Stones greater than 1 mm in diameter were consistently visualized in vitro using higher frequency transducers, lower intensities, and simple sector scanning techniques in different planes. All stones greater than 3 mm demonstrated consistent posterior acoustic shadowing, similarly facilitated by use of these techniques. The demonstration of posterior acoustic shadowing does not relate to the calcium content, shape, surface characteristics, or specific gravity of the stone.


Surgical and pathologic correlation of cholecystosonography and cholecystography.

To define the accuracy of varying ultrasonic patterns in the diagnosis of gallstones, the records of 145 patients with ultrasound examination of the gallbladder prior to cholecystectomy were reviewed. Three abnormal scan categories were established: category 1--shadowing opacities that move with gravity within the gallbladder lumen; category 2--nonvisualization of the gallbladder lumen; and category 3--nonshadowing opacities within the gallbladder lumen. The accuracy of these criteria for gallstone diagnosis was found to be 100%, 96%, and 61%, respectively. Overall accuracy was 96% for gallbladder disease, with a 4% false negative rate. Oral cholecystography demonstrated an accuracy of 93% in this series. A preoperative ultrasound diagnosis of gallstones should probably be limited to category 1 and 2 appearances only.


Prone view ultrasonography for pancreatic tail neoplasms.

Ultrasonography was performed in the prone and supine positions in six patients with neoplasms in the tail of the pancreas. The masses were either not apparent (three cases) or less well visualized on the supine scans. The value and indications of the prone position in the ultrasonic evaluation of masses in this portion of the pancreas are documented. Prone scanning is particularly useful when malignant ascites interferes with pancreatic visualization in the supine position.


Ultrasonography of primary cysts of the liver.

Primary liver cysts may cause diagnostic uncertainty when evaluated by conventional means. Ten cases of simple or multiple cysts unassociated with polycystic renal disease were studied. Ultrasonography was demonstrated to be the most accurate technique for visualizing these lesions and establishing their cystic nature.


Ventilation-perfusion scans in neonatal regional pulmonary emphysema complicating ventilatory assistance.

Two cases of ventilator-related neonatal lobar overexpansion with similar radiographic appearance, but probably different pathogenesis, are presented. In one infant, persistent interstitial lobar emphysema was confirmed by markedly decreased perfusion shown on scintigraphy; this information was of great value in predicting the beneficial effect of lobectomy. In the other case, ventilation and perfusion scans indicated functional value of the emphysematous lobe and correctly suggested conservative management. Radioisotope lung scans may provide valuable information regarding lung function in regional pulmonary emphysema associated with assisted ventilation in neonatal respiratory distress syndrome, and thus determine patient management.


Detection accuracy in chest radiography.

The detection accuracy of the diagnostic radiologist is important in everyday medical decision making. However, little work has been done relating the detection accuracy of the radiologist to the quality of the image. This study, using a thorax and lung phantom, simulated tissue-equivalent 6.4 mm lesions, and a 183 cm source-to-image distance, shows that the detection accuracy is not dependent on the focal spot size (over a range of 0.3-2.0 mm). However, the false positive rate increases when using small focal spots. In addition, the detection accuracy decreases with increasing root-mean-square (RMS) noise (a measure of the amount of quantum mottle in the image), while the false positive rate and intraobserver disagreement increase with increasing RMS noise. It is also shown that the nonradiologist responds to changes in noise in exactly the same way as the radiologist.


Bronchography in the recognition of congenital cystic bronchiectasis.

Congenital cystic bronchiectasis is an uncommon disease. Most of the reported cases have been in infants and young children. This paper presents four cases of older children and younger adults who had congenital cystic bronchiectasis. Distribution of the disease is lobar or may even involve an entire lung. Bronchography plays an important role in the diagnosis of congenital cystic bronchiectasis. The three important bronchographic signs of congenital cystic bronchiectasis are: (1) absence of contrast filling of the bronchial glands duct; (2) contrast filling of numerous cysts which communicate directly with the bronchial tree; and (3) nonvisualization of normal lung parenchyma within the area of involvement.


Laryngocele.

Laryngocele occurs more commonly than the literature indicates. Until recently, most were diagnosed clinically in the symptomatic patient. Although laryngocele is usually asymptomatic, greater numbers are being diagnosed because more patients suspected of head and neck cancer are undergoing sophisticated diagnostic radiographic procedures. Of 2,068 patients studied at M.D. Anderson Hospital and Tumor Institute for suspected laryngeal or hypopharyngeal cancer, 87 (4.2%) had laryngoceles. Three types of laryngocele are recognized: internal, external, and combined. They may be congenital or acquired and occur at any age. The coexistence of carcinoma and laryngocele has been discussed often enough in the literature to suggest a direct relationship; however, this series yielded no substantive evidence to implicate laryngocele as a precursor of carcinoma. The radiographic procedures currently used which readily establish the presence of laryngoceles are lateral soft tissue radiography of the neck, anteroposterior tomography of the larynx, and contrast laryngography.


Benign pneumoperitoneum following median sternotomy incision.

Because of the close anatomic relationship of the pericardium, diaphragm, and peritoneal cavity, a benign pneumoperitoneum may occur following median sternotomy incision and cardiac surgery. The pneumoperitoneum results from inadvertent opening of the peritoneal cavity during the initial surgical incision or during the subsequent cardiac surgery. It is generally of no significance to the patient, although it must be distinguished from pneumoperitoneum occuring secondary to intraabdominal pathology or to retrograde dissection of extraalveolar air in patients on ventilatory support. Two illustrative cases are presented.


Radiographic spectrum of pleuropulmonary tularemia.

Pleuropulmonary disease was seen in 50 of 62 patients (81%) with proven tularemia. Radiographic findings included patchy subsegmental air space opacities (74%), hilar lymphadenopathy (32%), and pleural effusion (30%). Less common manifestations were air space opacification of an entire lobe or segment, cavitation, oval opacities, pericardial effusion, linear opacities and septal lines, apical and miliary disease resembling tuberculosis, a mediastinal mass, empyema with bronchopleural fistula, and residual cystic changes, calcification, and fibrosis. Pleuropulmonary tularemia may be easily misdiagnosed as other infectious diseases, neoplastic diseases, and occasionally cardiac or other pericardial disease. It should be considered whenever patients from endemic areas present a perplexing radiographic and clinical picture. Such patients should have the benefit of a serologic examination for tularemia, since this disease may be effectively controlled with appropriate antibiotics.


Selective involvement of the first carpometacarpal joint in scleroderma.

Selective involvement of the first carpometacarpal joint is described in four women with scleroderma. Radiographic abnormalities at this site included osseous erosion, radial subluxation of the metacarpal base, and (in two patients) intraarticular calcification. Perlarticular osseous erosions were noted at adjacent locations in three patients. The cause of this distinctive wrist finding in scleroderma is unknown, but its similarity to alterations in other connective tissue diseases suggests that muscular and tendon imbalance may be important in producing bone erosion and subluxation at this articulation.


Pseudocysts of the humerus.

Two patients are described who had areas of rarefaction in the humeral heads that were biopsied and found to be normal bone. Almost all humeral heads have an area of localized rarefaction laterally, and when very pronounced this can be confused with a lytic lesion. These pseudocysts are so radiographically characteristic that they should not be biopsied.


Proximal femoral focal deficiency.

Proximal femoral focal deficiency, a distinct clinical and radiographic entity that results in leg length discrepancy, has received little attention in the radiographic literature. Thirteen patients were studied and the degree of deficiency established using radiographic criteria. The full extent of hip instability often could not be ascertained on radiographs obtained during the first year of life. Hip arthrograms combined with cine radiography can establish the presence of an unossified femoral head and aid in evaluating the degree of hip instability. Unlike other causes of leg length discrepancy, such as congenital idiopathic coxa vara, proximal femoral focal deficiency is often associated with other congenital bony anomalies, most commonly ipsilateral absent or hypoplastic fibula.


Routine oblique radiography of the pediatric lumbar spine: is it necessary?

A series of 86 pediatric lumbar spine abnormalities was evaluated to determine the diagnostic benefit of radiography in oblique projection as compared to frontal-lateral projections alone. In only four patients was an abnormality apparent on the oblique view which had not already been demonstrated by the frontal-lateral series; each of these represented an isolated spondylolysis. Because the diagnostic yield was low at a patient cost of more than double the gonadal radiation dose, it is recommended that oblique views be eliminated in the routine radiography of the pediatric lumbar spine.


Remote effects of neuroblastoma.

Neuroblastoma, which is primarily an extracranial disease, has remote manifestations which can be confusing. Neurologic signs and symptoms such as opsoclonus (dancing eyes), ataxia, blindness, and cord paralysis may precede by several months the manifestations of the primary tumor in a distant site such as the abdomen. Descriptions of nine cases demonstrate the various modes of presentation and some of the unusual aspects of this disease. The recent advent of computed tomography requires a reevaluation of the neuroradiologic approach to the evaluation of neuroblastoma.


Hysterographic double-outlined uterine cavity: a sign of unsuspected pregnancy.

A review of three hysterograms inadvertently performed during early pregnancy reaffirms the regular appearance of infiltration of aqueous opaque media into the substance of the decidua, producing the sign of the double-outlined uterine cavity. Although such endometrial opacification may also occur during the late secretory phase, its recognition should arouse suspicion of pregnancy. A coexisting intrauterine filling defect may then be more confidently diagnosed as an amniotic sac.


Incudostapedial joint in health and disease.

The incudostapedial joint was studied in tomograms of 370 normal and 80 diseased middle ears. The Guillen view was found to be superior to the anteroposterior view in demonstrating this joint in normal middle ears (85% and 62% visualization, respectively). In the presence of disease, visualization was markedly reduced to 19%; this lack of visualization is a nonspecific finding since early cholesteatomas, chronic otitis media, and retraction pockets could not be differentiated radiologically. Nonvisualization of the incudostapedial joint in the Guillen view is a more objective indicator of middle ear disease than such terms as "indistinct of hazy" middle ear cavities.


Accuracy of computed tomography in detecting intraabdominal and pelvic adenopathy in lymphoma.

Computed tomography (CT) is a highly accurate method of detecting intraabdominal and pelvic nodal involvement in patients with lymphoma. The correlation between CT and lymphangiographic findings in this series of 80 surgically proven and nonproven cases was high (84%). CT is superior to lymphangiography in demonstrating abnormality in such areas as the high retrocrural or the mesenteric nodes where contrast material from bipedal lymphangiography does not reach. An abnormal CT scan eliminates the need for lymphangiography, and normal CT scan at 2 cm intervals can exclude retroperitoneal adenopathy with high confidence. If details of internal nodal architecture are required, a lymphangiogram can also be performed. Lymphangiography is also indicated in patients where CT is equivocal either because of lack of fat or gross motion artefacts.


Mitral valve repair for significant mitral insufficiency.

There has been skepticism since the early days of open heart surgery that good long-term or even short-term results were possible with repair of pure mitral insufficiency. The authors report 145 patients in whom a markedly insufficient mitral valve was repaired 6 months to 17 years previously and another 55 patients in whom repair of the insufficient mitral valve was performed along with myocardial revascularization from 6 months to 7 years previously. Comparative data with other published work reveals superior results with repair than with replacement with Starr-Edwards and Hancock glutaraldehyde-treated porcine valves and with far less emboli. Conservatism is urged in operating upon patients with mitral insufficiency. Repair of the valve rather than replacement is stressed for those patients requiring surgery.


Origin and differentiation of the yolk sac and extraembryonic mesoderm in presomite human and rhesus monkey embryos.

Reexamination of presomite human and rhesus monkey embryos in the Carnegie Collection provides no evidence to corroborate the hypothesis that the trophoblast is the source of all extraembryonic tissues in these embryos. Instead, the present study indicates that the developmental pattern of the yolk sac and extraembryonic mesoderm is homologous to that in other eutharian mammals. The primary yolk sac of 10- to 11-day human blastocysts is partially filled with a meshwork of extraembryonic endoderm, whereas such a meshwork is absent in the rhesus monkey. It is suggested that this endodermal meshwork develops as the result of interstitial implantation in the human embryo. A small secondary yolk sac develops in 12- to 13-day human and macaque embryos as the result of pinching off of a portion of the larger primary yolk sac. Development of a secondary yolk sac in higher primates appears to be related causally to differential rates of expansion of the blastocyst and primary yolk sac within the simplex uterus. The caudal margin of the primitive streak develops precociously in 12- to 14-day human and macaque embryos, and this appears to be the source of all the extraembryonic mesoderm of the chorion, chorionic villi, and body stalk. It is suggested that the peripheral spread of extraembryonic mesoderm plays in inductive role in the development of chorionic villi, similar to other types of epithelial-mesenchymal inductive interactions. In contrast to previous hypotheses, the human and macaque trophoblasts appear to give rise only to additional trophoblast.


The ovoimplantation of Microcebus murinus Miller. (Primates, Lemoruoidea, Strepsirhini).

The process of nidation of Microcebus murinus may be subdivided into several stages (preadhesion, apposition, attachment and invasion), as is indicated for protracted phases of preimplantation. Not until the apposition stage does the inner cell mass orient itself orthomesometrially, while concurrently a nidation plaque develops in the abembryonal trophoblast that overlies and resorbs the coalescent glands. During the subsequent adhesion stage, the paraembryonal, bilaminar omphalochorion becomes attached to the uterine epithelium, with focal resorption of the latter. In addition, chorionic vesicles begin to develop. In the meantime, the embryonic disc has lost its trophoblastic cover as a preliminary to the formation of the pleuramnion. The formation of a nidation plaque, together with the subsequent central implantation of Microcebus, suggests a close relationship to Loris tardigradus, characterizing the mode of implantation of Strepsirhini. The nidation plaque and its invasive capacity, giving rise to a syndesmochorial placental nucleus, provide a placentological link to Galago demidovii.


Studies on 3-methylhistidine metabolism in children with protein-energy malnutrition.

Twenty-four hour urinary excretion of 3-methylhistidine (3-MeHis) was determined in children suffering from severe and moderate degrees of protein-energy malnutrition before and after treatment. Excretion of 3-MeHis was decreased both in children with severe protein-energy malnutrition and during undernutrition and increased considerably after treatment. The results suggest that there is a quantitative as well as a qualitative change in 3-MeHis metabolism in protein-energy malnutrition. A sensitive index for studying muscle protein metabolism is not available so far. Studies reported herein seem to suggest that 3-MeHis may fulfill such a requirement.


Nutrition and fertility: some iconoclastic results.

In this paper, the evidence available is used to conclude that, as levels of nutrition increase from insufficient to excessive, fertility first increases and then decreases. This suggests that the relationship between fertility and nutrition has the shape of an inverted U. Next, the hypothesis is explicitly tested using countries as units of observation. In the statistical analysis, the possibility of spurious relationships is carefully controlled. The results strongly support the hypothesis that, for existing levels, additional intake of nutrients decreases the levels of fertility.


Chymotrypsinlike activity of some intestinal bacteria.

Some tests of exocrine pancreatic function are based on the estimation of intestinal chymotryptic activity by using specific substrates such as N-benzoyl-L-tyrosyl-PABA (BT-P). In this study the action of a number of bacteria isolated from human or monkey intestines on BT-P was investigated. The monkeys studied had an intestinal flora closely resembling that of man. Except for Bacteroides, Proteus vulgaris No. 73, Proteus morgani No. 202, and Pseudomonas aeruginosa No. 76, significant splitting of BT-P did not take place when the common enteric microorganisms were tested. It was concluded that with the possible exception of bacterial overgrowth of the small bowel, microbial chymotryptic activity is not of importance.


In utero diagnosis of Gaucher disease.

Beta-Glucosidase activity measured by synthetic substrate at pH 4.6 was low in the cultured amniotic cells from two pregnant women at risk for juvenile and adult type Gaucher disease. The diagnosis was confirmed by showing a low activity of beta-glucosidase in the skin fibroblasts with a synthetic substrate or in the spleen with a natural substrate, and by ascertaining the presence of Gaucher cells in the fetal tissues. However, considerable activity of beta-glucosidase measured with synthetic substrate was found in the liver of both affected fetuses and in the spleen of one. It is advisable that the determination of beta-glucosidase to confirm prenatal diagnosis of Gaucher disease be done either in the cultured skin fibroblasts or in the spleen, and if in the spleen, with a natural substrate rather than a synthetic one.


Increased doses of phenytoin for infants.

A case report describing the problems of using conventional phenytoin dosages to achieve control of myoclonic seizures in a 6-month-old infant weighing less than 10 kg is presented. The physiologic explanations for the necessary phenytoin dosage adjustment in infants weighing less than 20 kg are discussed. It is suggested that more rapid metabolism, a larger volume of distribution and impaired gastrointestinal absorption may be responsible for the higher phenytoin dosages needed in such patients. Methods of determining appropriate dosage regimens, based on Michaelis-Menten pharmacokinetic principles or on body surface area, are discussed. Monitoring of plasma phenytoin concentrations is necessary to provide therapeutic levels of phenytoin and to prevent toxicity.


Experimental and clinical data on the insertion of the levator palpebrae superioris muscle.

Radiographic and electron microscopic evidence showed that the upper eyelid skin crease is formed by the insertion of the levator palpebrae superioris muscle into the septa between the orbicularis muscle into the septa between the orbicularis muscle bundles and not into the skin itself. Experiments on monkeys showed that the insertions of the aponeurosis and of Müller's muscle both contribute to normal eyelid elevation. No histologic evidence was found for a disinsertion of Müller's muscle in 20 cases of blepharoptosis. This, with other evidence discussed, supports the functional importance of the human aponeurotic insertions in eyelid elevation.


The ultrastructure of the retina in adult metachromatic leukodystrophy.

A 46-year-old woman afflicted with biochemically proven metachromatic leukodystrophy had only mild optic atrophy shortly before her death. Repeated earlier ophthalmoscopic examinations had not revealed any retinal abnormalities. Light microscopy of the retina showed strong acid phosphatase activity in both enlarged ganglionic cells and pigment epithelial cells. Demyelination of both optic nerves was not noted. Ultrastructurally, membranous lysosomal residual bodies were confined to ganglionic cells. We found lipofuscin material in pigment epithelial cells, but also within metachromatic leukodystrophy-specific residual bodies of ganglionic cells. The presence of lipofuscin represents the "wear-and-tear" phenomenon, possibly enhanced by the metachromatic leukodystrophy.


Glenn A. Fry Award Lecture--1977. The ocular effects of ultraviolet radiation.

The author reviews the previous known effects of UV radiation on the eye together with results obtained on human and animal eyes in his laboratory during the past 11 years. Damage to the cornea and lens is assessed, classified, and discussed. Methods of calculating safe UV exposures and establishing characteristics of protective devices are presented.


A sensory mechanism for amblyopia: electrophysiological studies.

Steady-state visual evoked potentials were elicited by the appearance/disappearance of sinusoidal gratings of varying spatial frequency for both eyes of amblyopic subjects at temporal frequences from 2--32 Hz. The amblyopic eyes showed reduced responses relative to those of the nonamblyopic eyes across a wide range of spatial frequencies, the difference between the 2 eyes being most marked for high spatial frequencies and low temporal frequencies. Both the nonamblyopic and the amblyopic eyes showed a linear relation between the evoked potential amplitude and the logarithm of the stimulus contrast; however, the slope of the line was flatter for the amblyopic eyes. Possible neural mechanisms for the amblyopic eyes' reduced responses to spatial contrast are considered.


Psychotherapy of the child with true brain damage.

Psychotherapy of the child with true brain damage presents special problems and requires special approaches. Those who are cognitively primitive--at the sensorimotor or preoperational stage of development--require a crisis approach; those at the concrete or formal operational stage can be treated with a modified insight-oriented approach. Development of a therapeutic alliance, establishment of workable defense mechanisms, identification and clarification of unalterable cognitive defects and issues of termination unique to this special population are discussed.


Dietary and dental variations in the genus Lemur, with comments concerning dietary-dental correlations among Malagasy primates.

Field studies of feeding in the lemur subspecies Lemur fulvus rufus and L. f. mayottensis have revealed that feeding patterns within a single species can be markedly different, both regionally and seasonally. Thus L. f. rufus is a dietary specialist (3 plant species accounting for 80-90% of feeding time), and is highly folivorous, especially during the dry season (90% of feeding time spent eating leaves during the dry season, and 53% during the wet season). On the other hand, L. f. mayottensis is more generalized dietarily (the parts of 12 plant species accounting for 90% of feeding time), and is primarily frugivorous (64% of feeding time spent eating fruit, with a monthly maximum during the wet season of 79%. In both these respects, L. f. mayottensis resembles L. catta are more closely thant it does L. f. rufus. When size differences are corrected for, Lemur fulvus rufus has significantly longer second lower molar shearing crests than does L. f. mayottensis. Other folivorous Malagasy strepsirhines also tend to have long shearing crests than frugivorous forms. Some data on cheirogaleines also suggest that the more insectivorous species have better developed molar crests than frugivorous species. Some apparent exceptions to this pattern are noted, especially for Lemur catta, which in certain functional respects dentally more closely resembles L. f. rufus than L. f. mayottensis. The problems of dietary classifications are discussed.


Spectrographic analysis of laryngeal air sac resonance in rhesus monkey.

Laryngeal air sacs are circular out-pocketings, located in the hyoid bone with their ostium in the midline of the anterior part of the larynx. From previous cadaver studies of the rhesus monkey it was deduced that the function of the air sac is to act as a resonating chamber. The present study was designed to test this hypothesis. Recordings were made of three rhesus monkeys before and after surgical removal of the air sac. Spectrographic analysis of the monkeys' vocalizations indicated that differences in formant frequency characteristics between pre-and post-surgical recordings were negligible. This finding suggests that the laryngeal air sac does not play an important role in the resonant properties of the monkeys' vocal tracts.


Relative femoral head size in early hominids.

Relative growth of the human femur head is studied by a logarithmic principal components method. Growth rates differ according to the population sampled and the other body dimensions being compared, and especially according to sex. The results do not support biomechanical assumptions of strongly positive allometry of the femur head, which have been used to argue that the australopithecine hip joint was not relatively small.


Fore- and hindlimb proportions in Plio-Pleistocene hominids.

Associated fore- and hindlimb parts of five individuals are known from the hominid Plio-Pleistocene fossil collections in Africa. Four of these have been classified as Australopithecus and show definite evidence that in comparison with humans, forelimbs were relatively large and hindlimbs were relatively small. The fourth individual, placed in the genus Homo, has human proportions. These findings do not necessarily imply locomotor differences: the forelimbs may have been relatively long in Australopithecus simply because they were as yet not completely reduced from their generalized hominoid ancestral state.


Homologies of the toothcomb.

A recently described juvenile specimen of Avahi was supposed to show that indriines have an unreplaced deciduous canine and that the indriine toothcomb was composed only of incisors. To the contrary, this specimen demonstrates quite dramatically a growth phenomenon earlier discussed: in indriines, the anteriormost of the four deciduous lower teeth posterior to the toothcomb migrates mesially toward the toothcomb (Schwartz, '74). In this particular Avahi, this tooth has even become associated with the toothcomb. The alignment of this tooth with the toothcomb is a strictly impermanent situation and cannot be taken into consideration when determining homologies of the teeth of the toothcomb. Morphologically and developmentally the lateral teeth of both indriine and lemur and loris toothcombs are similar to each other and distinct from the central set of teeth. Thus, if the lateral teeth of the lemur/loris toothcomb are canines, then the lateral teeth of the indriine toothcomb are canines as well.


The functional significance of the squamosal suture in Australopithecus boisei.

A juvenile Australopithecus boisei specimen from the Omo basin, southern Ethiopia, is found to exhibit and extraordinarily large overlap of the temporal squama on the parietal, a phenomenon shared with at least two adult specimens of A. boisei. An attempt is made to interpret the overlap as a structural (bony/ligamentous) adaptation necessitated by the unique combination of certain components of the masticatory system of A. boisei. These are: (1) the massiveness and strength of the temporalis muscle, (2) its relatively anterior location, and (3) the lateral position of the masseter muscle due to the flaring of the zygomatic arches. The effect of the temporalis muscle is to create excessive pressure on the portion of the squamosal suture along the parietal, while the lateral placement of the masseter and the resultant increase of pressure on the temporal squama via the zygomatic arch tend to "loosen" the contact between the temporal and parietal bones.


Early hominid enamel hypoplasia.

Enamel hypoplasia in the South African Plio-Pleistocene fossil hominid sample is examined. The Swartkrans hominids are shown to have a higher incidence of hypoplasia than the Sterkfontein hominids. Within the Swartkrans sample, individuals with hypoplasia of the first upper molar have lower-than-expected ages of death. Possible taphonomic explanations for these observations are discussed.


Implantation of cranial base metallic markers in nonhuman primates.

Cranial base metallic markers are useful in growth and developmental research on the nonhuman primate model. Metallic implants aid in superimposing serial cephalometric roentgenograms in the study of craniofacial changes. They also enable measurement of linear and angular changes in the cranial base. The design of a special implant gun is described in detail. A suggested technique for placement of tantalum markers in the cranial base of nonhuman primates is discussed.


Scaling of organ weights in Macaca arctoides.

The allometric scaling of nine internal organs was examined for Macaca arctoides. Significant organ weight-body weight regressions were obtained for heart, lungs, kidneys, pancreas, thyroid, liver, and testes. The spleen and adrenal glands exhibited strong variability and were only loosely correlated to body weight. Using allometry as a criterion of subtraction, observed sex differences in mean organ weights were seen to be primarily the result of differences in average body weight. It is postulated that analysis of observed differences in organ weights between this species and Macaca mulatta would yield similar conclusions. Comparison of intraspecific slope values obtained in the present study with interspecific values reported in the literature reveals a pattern paralleling the brain-body weight relation. A discussion of the relationship between intra- and interspecific slopes is presented.


Histaminergic pharmacology of primate lower esophageal sphincter.

We have studied the lower esophageal sphincter (LES) response to exogenous histamine and to H1- and H2-blocking agents in the awake baboon. Increasing intravenous bolus doses of histamine produce an increase in LES pressure with a maximum response at a dose of 12 microgram/kg. H1-receptor blockade with chlorpheniramine over a wide dose range did not alter basal LES pressure but did abolish the response of the LES to exogenous histamine. H2-receptor blockade with cimetidine at doses markedly inhibiting gastric acid secretion (2 mg/kg.h) did not alter basal LES pressure or the response of the LES to exogenous histamine. In addition, cimetidine did not alter the response of the LES to pentagastrin and bethanechol. Although histamine and histamine receptors are important in gastric secretion, they appear to have no identifiable role in the maintenance of basal LES smooth muscle tone in the baboon. These results demonstrate the presence of a stimulatory H1 receptor on baboon LES smooth muscle, but provide no evidence for the presence of an H2-inhibitory receptor. As opposed to the parietal cell, the LES response to pentagastrin and bethanechol does not require a H2 receptor.


Calcium in the control of renin release.

The effect of Ca concentrations in the incubation medium and of estimated intracellular Ca concentrations on renin release was examined with use of pig renal cortical slices. In addition, the Ca requirement for the epinephrine stimulatory effect and for the ouabain inhibitory action on renin release was also tested. In mediums containing 5.9 mM K, variations in Ca concentration had no effect on renin release. In contrast, when the K concentration was 59 mM, a significant inhibition of renin release was attained with all concentrations of calcium. The inhibition of renin release in high K mediums by Ca was attributed to an increase in the intracellular Ca concentration. In addition, both the stimulatory effect of epinephrine and the inhibitory effect of ouabain on renin release required Ca in the medium. These results support the hypothesis that the control of renin secretion is mediated, in part, by changes in the intracellular concentration of Ca, most likely in the juxtaglomerular cells.


Photoelectric method for estimating hemodynamic changes in regional cerebral tissue.

A new photoelectric method for measuring hemodynamic changes in a thin layer of cerebral tissue in situ is described. The apparatus consists of a miniature lamp of 0.7 mm OD and a photodiode with a color filter having maximum light transmission at 548 nm. The lamp was chronically or acutely implanted into the brain tissue of animals as a light source, and the intensity of the light transmitted through the cerebral tissue was monitored with the photodiode from the brain surface. The intensity of the transmitted light was quantified for cerebral blood volume (CBV). The mean transit time of blood (t) was obtained from tissue hemodilution curves produced by saline injection into the carotid artery. The regional blood flow was calculated from the values of CBV and t according to the Stewart-Hamilton equation. The apparatus was shown to be stable, rapid in response, easy to operate, and to give reproducible results. Possible sources of error are discussed.


Accuracy of the regulation of caloric ingestion in the rhesus monkey.

In seven male monkeys, Macaca mulatta, the infusion of nutrients into the stomach just prior to or 20 h before a 4-h feeding period reduced the feeding by an amount comparable to the calories infused. Pure carbohydrates, fat, protein, and mixtures were employed as infusions and given in a random fashion over a caloric range of 75-300 kcal. In a second series of experiments, monkeys were partially fasted on 1 day and in this way deprived of 75, 150, 300, or 450 kcal. On successive days, they overate to compensate for this deprivation. The smaller deprivations (75 and 150 kcal) were corrected on the first recovery day. The 300-kcal deprivation required 2 days to be corrected while the 450-kcal deficit was only partially restored. These experiments demonstrate the capacities of the monkey to respond with precision to caloric supply and deprivation so as to maintain a constant caloric intake.


Immunoglobulin concentration in treated human acute Chagas disease. A follow-up study.

Immunoglobulin M, G, and A concentrations were studied by radial immunodiffusion technique in 16 individuals (two were 16 and 14 yr of age, respectively, while the remaining 14 uere 15 yr of age or less) with acute Trypanosoma cruzi infection. Serum samples were obtained from these patients beginning with the onset of symptoms and continuing until several months after treatment with nifurtimox was completed. Soon after infection the concentration of IgM was higher than the average found in healthy children. Some of the samples also had higher values than those found in children with other acute infections. At this time isolated increases in IgG and/or IgA concentrations were also found in T. cruzi-infected patients. Immunoglobulin concentrations had usually returned to normal when treatment with nifurtimox was completed, both in the patients with negative serology and in those who remained positive. However, some of the sera showed isolated higher IgM, IgG, and/or IgA values than those found in healthy controls.


Purification of a specific antigen of Trypanosoma cruzi from culture forms.

A monospecific rabbit antiserum was prepared against a specific component of Tryanosoma cruzi epimastigote culture forms (designated antigen 5). Rabbits were immunized intradermally in 30-50 sites with the zone of agarose gel in which the component 5:anti-5 complex was visualized after two-dimensional immunoelectrophoresis. With this appropriate antiserum and the total epimastigote soluble extracts, the specific component of T. cruzi was purified by immunoadsorption. Purity and specificity controls of thefinal product were carried out by prolonged immunization of rabbits, and then by immunoelectrophoretic and two-dimensional electrophoretic analyses.


Evaluation of serodiagnostic tests for visceral larva migrans.

Four serologic techniques for the diagnosis of visceral larva migrans caused by Toxocara canis, namely indirect hemagglutination (IHA), bentonite flocculation (BF), enzyme-linked immunosorbent assay (ELISA), and double diffusion in agar (Ouchterlony), were evaluated using sera sent to the Center for Disease Control from patients with a presumptive diagnosis of visceral larva migrans (VLM). Patients having 5-6 of the clinical or laboratory criteria for VLM were designated as cases while those with 0-2 criteria served as controls. The sensitivity of the ELISA was 78.3% compared to 18.2%, 25.8% and 65.2% for the IHA, BF, and Ouchterlony, respectively; the sepcificity of all four tests was greater than 92%. The predivtive value of positive test was greater than 85% for all tests except the IHA, while the predictive value of a negative test was greater than 85% only for the ELISA. The results of a ELISA were reproducible in different laboratories. Based on these findings, the ELISA using a larval antigen appears to be the serodiagnostic method of choice for VLM.


Crimean-congo hemorrhagic fever, Thogoto, dugbe, and Jos viruses isolated from ixodid ticks in Ethiopia.

From 1974 through 1976, U.S. Naval Medical Research Unit No. 5 isolated 25 strain of tick-borne virus in infant mice from 410 pools containing over 6,000 ticks, and one strain from a bird and one strain from a rodent collected in central and southern Ethiopia. Of these, 17 were identified as known viruses previously found in West Central and East Africa. There were 8 strains of Jos virus from Amblyomma ticks; 7 strains of Dugbe virus from a bird, a rodent and from ticks; 1 strains of Crimean-Congo hemorrhagic fever virus and 1 strain of Thogoto virus from ticks.


Indirect calorimetry as a guide to caloric replacement during total parenteral nutrition.

Fifty patients were studied by indirect calorimetry to assess caloric needs. Seventeen patients received total parenteral nutrition (TPN) in a fixed dose of 45 +/- 3 kcal/kg. Thirty-three patients were studied after acute injury. Indirect calorimetry and the basal energy expenditure equation (BEEE) were compared. In male patients receiving TPN, indirect calorimetry more closely approximated caloric needs than did the BEEE X 1.75. In female patients, the BEEE X 1.75, indirect calorimetry value, and calories infused were more equivalent, and positive nitrogen balance was consistently achieved. In thirty-three trauma patients, indirect calorimetry and the BEEE were compared. Indirect calorimetry consistently predicted higher caloric expenditure than did the BEEE X 1.75. In assessing caloric requirements in acutely catabolic patients, the BEEE X 1.75 appears to be inadequate. The BEEE does not take into account changes in temperature or degree of illness. Indirect calorimetry is easy to perform and gives more pointed information about the patient's caloric needs.


Clinical utility of CAT body scans.

The results of 202 computerized axial tomography (CAT) body scans performed on hospitalized patients were analyzed for their accuracy and clinical utility. The sensitivity (80 per cent), specificity (70 per cent), and accuracy (77 per cent) were high but not superior to ultrasound examinations of the same area. The results of the CAT body scan affected patient management in 16 per cent of patients and affected the success of treatment in 1 per cent of patients. We conclude that for many abdominal conditions ultrasound scans are equally as accurate and substantially more cost-effective than CAT body scans, and that the clinical value of CAT body scans needs support from controlled clinical trials.


Histopathologic and electron microscopic studies of cutaneous lesions in calves with experimentally induced East Coast fever (theileriosis).

Skin lesions of bovine East Coast fever were examined by light and electron microscopy at 120 hours after attachment of Rhipicephalus appendiculatus ticks infected with Theileria parva. Lesions included epidermal ulcer, hemorrhage, edema, necrosis, and inflammatory cell infiltration by mostly polymorphonuclear and mononuclear (lymphoid) cells. The trophozoite state of T parva was observed in a parasitophorous vacuole and feeding on neutrophil granules. Schizonts, some in budding process, and merozoites were extracellular and among many mononuclear phagocytes (lymphoid cells). Some merozoites were in mononuclear phagocytes and a granulocyte. Some of the cells had already transformed into lymphoblasts with pseudopodia.


Muscle function and structure of the esophagus of the baboon (Papio anubis).

A baboon (Papio anubis) was used as a model for the study of the physiology of the esophagus. This model closely resembles the human being phylogenetically and physiologically. Base-line lower esophageal sphincter pressure and peristaltic amplitude are similar to that of man. In addition, the anatomic transition from striated to smooth muscle is identical to that of the human esophagus. The sphincter-depressing effect of ketamine anesthesia was demonstrated.


Effect of staphylococcal enterotoxin B on cardiorenal functions and survival in X-irradiated rhesus macaques.

Pretreatment of rhesus macaques with nonlethal total-body x-irradiation (400 R) prolonged survival time from an average of 15 hours to 101 hours after intravenous (IV) inoculation of 50 microgram of staphylococcal enterotoxin B (SEB)/kg of body weight. Radiation exposure per se did not produce detectable cardiorenal changes; however, the longer survival after SEB challenge exposure in x-irradiated rhesus macaques was associated with improved cardiorenal functions if compared with that of nonirradiated macaques given the same dose of SEB. Total-body radiation exposure 4 days prior to IV SEB inoculation prevented typical SEB-induced decreases (where measured at 5 hours) in cardiac output, stroke volume, TcH2O, CPAH, Cosm, and urine flow, as well as increases in total peripheral and renal resistance. A theory concerning the significance of radiation-induced leukopenia on modification of SEB-induced cardiorenal functions is postulated.


Neonatal calf diarrhea caused by a virus that induces villous epithelial cell syncytia.

Intestinal lesions caused by a virus serologically unrelated to the calf diarrheal rotavirus or coronavirus were studied in gnotobiotic calves. The virion purified from feces from infected calves was a fringed particle with a diameter of about 100 nm. The incubation period from time of inoculation per orum to onset of diarrhea in calves was as short as 8 hours. The viral infection in bacteria-free calves or calves not contaminated with pathogenic bacteria caused severe illness for only 24 hours. When bacteria such as the K99 antigen Escherichia coli were present, the combined infection caused mortality. Lesions occurred only in the small intestinal villous epithelium. Calves euthanatized shortly before or after the onset of diarrhea had developed villous epithelial cell syncytia that contained numberous virions in the cytoplasm. Within 2 to 3 hours after onset of diarrhea, the infected cells were shed and the villi had denuded tips or had cuboidal to squamous epithelial cells.


Effect of low temperature on growth, viability, and synthesis of mycolic acids of Mycobacterium tuberculosis strain H37Ra.

Cultures of Mycobacterium tuberculosis strain H37Ra were grownto early logarithmic phase at 37 degrees C and were incubated at 16 degrees, 20 degrees, and 25 degrees C.  The decrease in this ability was more rapid at 20 degrees C than at 16 degrees C. Low-temperature incubation caused decreases in the ratios of mycolic acids and monounsaturated C16-19 fatty acids relative to the total of fatty acids synthesized. It also caused an increase in the ratio of saturated C24-26 fatty acids relative to the total of fatty acids synthesized. These ratios were based on the incorporation of radiolabel from 14C-acetate into fatty acids. These results showed that when M. tuberculosis H37Ra was incubated at low temperatures, it did not adapt by increasing the ratio of unsaturated to saturated fatty acids synthesized. The ability of the cells to synthesize mycolic acids was sharply decreased. These changes may lead to the loss of viability of M. tuberculosos H37Ra. Mycolic acid synthesis is similarly affected by exposure of cells to isoniazid, an antimycobacterial drug.


An investigation of the mechanism of ethanol-induced bronchoconstriction.

A 28-year-old Asian-American woman complained of symptoms of acute bronchoconstriction after drinking alcohol beverages. We documented the presence of ethanol-induced bronchoconstriction in this patient by administering oral ethanol challenges under controlled conditions. Bronchoconstriction was not prevented by pretreatment with atropine sulfate or cromolyn, suggesting that neither cholinergic postganglionic pathways nor mediator release from mast cells was the cause of the acute airway narrowing. The rapid decrease in specific airway conductance after ethanol ingestion and the association with symptoms of vasomotor sensitivity suggest that ethanol may have acted in this patient by releasing one or more secondary mediators with vasoactive and bronchoactive properties.


Therapy with cromolyn sodium.

Cromolyn is a prototype of a new series of drugs, the pharmacologic activities of which may offer an entirely new approach in the treatment of asthma. Whereas bronchodilator drugs and steroids act primarily at tissue sites to counteract the effects of various toxic mediators released from tissue mast cells, cromolyn prevents the release of such mediators from mast cell membranes. The advent of cromolyn sodium therapy has been recognized as a significant advance by the pharmaceutical industry, which is rapidly developing a series of cromolyn-like drugs with similar properties. Many of these compounds are active orally, and some preliminary investigations suggest that they also could be clinically effective. Cromolyn has therapeutic value in immunologic and nonimmunologically induced bronchospasm, being particularly suited for conditions amenable to long-term prophylactic therapy. The risk-to-benefit ratio of cromolyn sodium therapy is excellent. Cromolyn sodium is an important adjunct in the treatment of asthma. By topical administration the drug has been effective in seasonal and perennial rhinoconjunctivitis and in selected cases of gastrointestinal allergy to foods.


Aspergillus flavus keratitis.

Corneal infection due to the species Aspergillus flavus is rare and often destructive. This report describes a case of Aspergillus flavus corneal ulcer that failed to respond to amphotericin B, pimaricin, and clotrimazole. The eye subsequently became phthisical. The rational approach to the management of fungal corneal infection is to culture or perform sensitivity tests on the isolated organism. Early surgical intervention should be done if the infection fails to respond to medical treatment, and if the disease process extends deep into the stromal tissue and anterior chamber. Fungal malignant glaucoma requires excisional keratoplasty, lens extraction, and anterior vitrectomy.


Genetics in keratoconus: A, B, O blood groups.

A, B, O blood group frequencies and Rh factors were studied in 69 white keratoconus patients and compared with 1,465 healthy white individuals. We did not detect a significant excess of any particular blood group among keratoconus patients. It was concluded that blood groups were not associated with keratoconus.


Management of pterygia: should thiotepa be used?

Pterygium, a common source of morbidity throughout the world, may appear to be an innocuous, easily excised lesion, yet it plagues the ophthalmologist by its high rate of recurrence, ranging from 20% to 30% after simple excision. Beta irradiation has been used by ophthalmic surgeons for many years. Another method of stemming the high percentage of pterygium recurrence is through local application of thiotepa, a radiomimetic drug that inhibits rapidly proliferating cells. The following report is a review of the literature from 1960 to 1977 on the role of thiotepa in treatment of pterygium, with emphasis on the complications of thiotepa administration. The recurrence rate after topical postoperative use of thiotepa ranges from 0 to 8%, with disturbing variance in results, depending on each investigator's definition of "recurrence", the length of follow-up, the type of pterygium, and the number of patients. The main reported complication from thiotepa's use has been depigmentation of skin around several patients' eyes, sometimes precipitated by exposure to the sun's rays.


Some ultrastructural aspects of the replication of a Yucaipa-like virus in Vero cells.

The replication in Vero cells of a Yucaipa-like virus isolated from a wild bird in West Africa (PLOC/Senegal/9/76) was studied with an electron microscope at days 6 and 8 post-inoculation. Viral nucleocapsids, 15 nm in diameter, were found in the cytoplasm, mainly beneath the cell membrane. Viral particles, 125 to 175 nm in diameter, were released from the cells by a budding process. No viral nucleocapsid could be observed within the nucleus of infected cells.


Placental permeability in the sheep.

The transplacental flux of different radiolabelled substances was measured, according to Fick's principle, in chronically catheterised pregnant sheep (124 to 143 days of gestation). Knowing the uterine blood flow, it was possible to calculate the net flux and derive a permeability coefficient, K. With 14C erythritol, K soon reaches its ultimate value, thus suggesting there is only one rate-limiting step to transfer and no significant middle compartment in the sheep placenta. The comparison of feto-maternal fluxes of different metabolically inert, lipid insoluble molecules (urea, erythritol, mannitol and Cr-EDTA) demonstrates a very sharp decrease in permeability as molecular size increases. The membrane behaves like a tight epithelium, with pores of of an approximate radius of 0.45 nm which allow but a poor passive diffusion. On the contrary, permeability to 3 methylglucose and 2 deoxyglucose is much too high for passive diffusion. Transfer competition between D-glucose and 3 methylglucose affords other evidence for a stereospecific monosaccharide carrier. The relationship between the presumably "active" sodium flux out of the fetus and the electrical potential difference across the placenta is discussed. The fetus is usually negative to the mother but the potential difference changes from day to day, and in twin gestation, the respective fetomaternal potentials seem to be independent. Acid infusion to the fetus increases the potential difference. The maintenance of this electrical or chemical gradients is taken as a consequence of the low passive permeability of the placenta.


Prostaglandins and regulation of the pulmonary circulation in the perinatal period.

Effects of indomethacin on pulmonary vasodilation caused by ventilation of the fetal lungs with air were evaluated in anesthetized, exteriorized fetal goats by means of an open-chest pump perfused lung preparation. When fetal lungs are ventilated with air, pulmonary vascular resistance decreases in two steps: 1) a rapid decrease in pulmonary vascular resistance during the first 30 seconds of ventilation, and 2) a slower decline which continues through the first 10-20 minutes of more of ventilation. Indomethacin has minimal effect upon the first component. The second component is absent following treatment with indomethacin. Effects observed with indomethacin were more pronounced in immature fetuses (less than 90% gestation), than in mature fetuses. Prostaglandin synthetase activity appears to have a role in the pulmonary vasodilation resulting from ventilation of the fetal lungs with air.


Microsporidian infection in the cyst wall of Trematode metacercariae encysted in fish.

Microsporidian infection is reported in Liza ramada (Risso), Mugilidae, from Bardawil Lagoon, Mediterranean coast of Sinai, in the fibroblasts of the metacercarial capsule of Heterophyes heterophyes (Siebold). Infection of the metacercarial cyst resulted in an hypertrophy of the cyst wall and degeneration and eventual death of the encapsulated metacercaria.


Nonsensory neglect.

Five monkeys trained to perform with the extremity contralateral to a stimulus had unilateral neglect induced by frontal and reticular formation lesions. Postoperatively the performance of the animals was abnormal only on ipsilateral stimulation, which suggests that the mechanism underlying neglect in these subjects is not deafferentation of sensory inattention but a defect of intention.


Anti-actin antibodies of human and rabbit origin.

The production of actin antisera in rabbits was described and their reaction in various immunological tests were compared with the results obtained with human anti-actin sera (smooth muscle antibodies). Even if the sera may react with different antigenic determinants of actin as suggested by results in immunoprecipitation and blocking experiments, the rabbit and human sera can be used for studies of cells with equal or similar results. A prerequisite was that the rabbit anti-actin titres were high. The difficulty in obtaining strong anti-actin sera in rabbits was confirmed.


Determination of immunoglobulin content of CSF based on light chain characteristics.

The immunoglobulin light chain (types kappa and lambda) content of normal cerebrospinal fluid is similar to that of normal serum. In inflammatory diseases of the central nervous system a shift in the k/l ratio in comparison to serum values, usually a relative increase of Igk, can be observed. This increase of the k/l ratio, though not specific for any disease, is most commonly found in multiple sclerosis. There is no correlation between the IgG content and the k/l ratio. The methods described here measure bound and free light chains simultaneously. The calculations show that free light chains are present in both normal and inflammatory CSF and that they appear to be of polyclonal origin. The detection of light chain abnormalities in CSF can be taken as an indicator of endogenous immunoglobulin production in the CNS and is of significance for the diagnosis of inflammatory CNS processes, especially when other signs of endogenous immunoglobulin production are absent.


Enhancing effect of passive immunization with mycobacterial antibodies on humoral and cellular immunity in BCG-infected mice.

The present paper is an attempt to get insight about the mechanisms involved in the enhancing phenomenon that occurs in bacterial infections. Mice infected with small doses of the BCG strain of M. bovis and treated with a M. tuberculosis H37Rv antiserum investigated at various intervals for their capacity to synthesize haemagglutinating antimyco-bacterial antibodies and to develop delayed hypersensitivity to PPD. As controls, BCG-infected mice were treated with the antiserum freed from its mycobacterial antibodies. It was found that the passive immunization of BCG-infected mice promotes the growth of bacilli in their spleen and induces a late formation of antimycobacterial antibodies which do not seem to be related to the development of delayed hypersensitivity.


[Increase in tetracycline activity by using surface-active substances].

The antimicrobial effect of cationic and anionic surface-active substances, i.e. catamine AB and sulphonol NP-3 respectively was studied in vitro with respect to gramnegative bacteria. In non-bactericidal concentrations catamine AB significantly increased the efficacy of tetracyclines, while the anionic compound had no such effect. The increase in the tetracycline activity was due to the antibiotic increased absorption (14C-oxytetracycline as an example) on the treatment of gramnegative bacteria with catamine AB and staphylococci with catamine AB and sulphonol NP-3, which was mainly associated with impairement of the cell membrane permeability by the surface-active substances.


Immunochemical relationship between natural haemagglutinins and immune antibodies in the toad (Bufo paracnemis).

Natural and induced antibodies from serum of Bufo paracnemis were isolated by specific immunoadsorption (natural antibodies and specific induced antibodies, respectively). Natural agglutinins specific to rabbit red blood cells (RRBC) showed, by immunodiffusion (ID) and by immunoelectrophoresis (IEP) against rabbit anti-B, paracnemis serum, at least three precipitation lines. Similar patterns were obtained with the specific induced antibodies. Immunochemical identity between natural and induced antibodies was observed by ID test. These results were assessed by repeatedly absorbing rabbit anti-Bufo serum with natural antibodies: these natural antibodies totally exhausted the activity of rabbit immune serum against specific anti-bovine serumalbumine and vice-versa. These reactions were studied using a very sensitive radioimmunodiffusion test. The heterogeneity of natural haemagglutinins and their identity with induced antibodies are discussed in relation with these experimental data.


Antimalarial activities of various 4-quinolonemethanols with special attention to WR-142,490 (mefloquine).

Pilot appraisals of the activities of a selected group of 4-quinolinemethanols against acute Plasmodium falciparum infections in owl monkeys indicated that compounds of this class are equally active against infections with chloroquine-resistant and chloroquine-susceptible strains and that this efficacy is not compromised by concomitant resistance to pyrimethamine, and in addition, identified three derivatives with outstanding activity (WR-226,253; WR-142,490; and WR-184,806). WR-142,490, the second 4-quinolinemethanol evaluated in the above model, was five times as active as chloroquine against infections with the chloroquine-susceptible, pyrimethamine-resistant strain and had a much larger therapeutic index. Expanded evaluations designed to support projected studies in human volunteers provided full confirmation of the pilot appraisals and in addition showed: (i) that the activity of WR-142,490 was a function of the total dose delivered, single doses being as effective as three or seven fractional doses administered over as many days; (ii) that intravenous administration of this agent was feasible and effective; and (iii) that the compound was at least as active against infections with P. vivax as against infections with P. falciparum. Companion studies in rhesus monkeys infected with P. cynomolgi showed that WR-142,490 lacked prophylactic or radical curative activity, but that it was as effective as chloroquine as a companion to primaquine in a combination curative drug regimen. The results of human volunteer and field trials agree well with comparable segments of these experimental evaluations.


Activity of three 8-hydroxyquinoline derivatives against in vitro dental plaque.

Three 8-hydroxyquinoline derivatives, assessed using an in vitro preformed dental plaque model system, were differentially inhibitory for four plaque-forming microorganisms.


In vitro susceptibility studies with netilmicin: comparison of a 10-microgram netilmicin disk with a standardized 10-microgram gentamicin disk.

Netilmicin is a new, semisynthetic aminoglycoside antibiotic active against some gentamicin-resistant gram-negative bacteria. In this study we compared a 10-mug netilmicin disk with the standardized 10-mug gentamicin disk in terms of their abilities to predict probable clinical susceptibility to netilmicin. The agar dilution procedure of the International Collaborative Study of the World Health Organization and the U.S. Food and Drug Administration standardized disk test procedure were used. The gentamicin disk failed to predict the clinical susceptibility to netilmicin of 26 of 118 isolates previously shown by the agar dilution technique to to be netilmicin susceptible. The netilmicin disk correctly predicted probable susceptibility of all 26 isolates, including 20 shown by the agar dilution procedure to be resistant to gentamicin. These studies demonstrate the need for a separate netilmicin disk for use in agar diffusion disk susceptibility tests.


Infection in acute leukemia patients receiving oral nonabsorable antibiotics.

During a 20-month period all acute nonlymphocytic patients (87 patient trials) receiving cytotoxic chemotherapy were placed on an oral nonabsorbable antibiotic regimen consisting of gentamicin, vancomycin, and nystatin in addition to an intensive program of infection prevention aimed at reducing exogenously acquired and body-surface potential pathogens. Although side effects of anorexia, diarrhea, and nausea were common, gentamicin-vancomycin-nystatin was ingested 80% of the study time. Microbial growth in gingival and rectal cultures was substantially reduced. The incidence of bacteremias and other serious infections was low. Pseudomonas aeruginosa, other gram-negative bacilli, and Candida species caused few infections along the alimentary canal, whereas infections of the skin (especially Staphylococcus aureus) were not reduced compared with those occurring in former years. A total of the 104 acquired gram-negative bacilli were gentamicin resistant; 5 subsequently caused infection. Thus, despite certain definite drawbacks, the use of oral nonabsorbable antibiotics to suppress alimentary tract microbial flora in combination with other infection prevention techniques in granulocytopenic cancer patients has proven feasible and tolerable and has been associated with a low order of life-threatening infections.


Effect of triethylenetetramine dihydrochloride on the antibiotic susceptibility of Pseudomonas aeruginosa.

A chelating agent, triethylenetetramine dihydrochloride, interacted synergistically in vitro with both gentamicin and carbenicillin against a clinical isolate of Pseudomonas aeruginosa designated Ps 15. The minimal inhibitory concentrations of carbenicillin and gentamicin for Ps 15 in a 50% serum-Trypticase soy broth were 250 and 72.9 mug/ml, respectively. However, addition of triethylenetetramine dihydrochloride to the 50% serum-Trypticase soy broth reduced the minimal inhibitory concentration of both antibiotics approximately 10-fold. A comparison of the growth of Ps 15 in 50% serum-Trypticase soy broth containing either of the antibiotics showed that a rapid decrease in the percentage of survivors only occurred when the chelating agent was present.


In vitro antibacterial activity of amikacin and ticarcillin, alone and in combination, against Pseudomonas aerurginosa.

In vitro antimicrobial susceptibility studies using amikacin and ticarcillin, alone and in combination, were performed on 20 strains of Pseudomonas aeruginosa. All strains were susceptible to amikacin, and ticarcillin was active against 16 of the 20 strains. Enhanced anti-pseudomonas activity could be demonstrated with the combination of amikacin and ticarcillin.


Thermophilic methanogenesis in a hot-spring algal-bacterial mat (71 to 30 degrees C).

Algal-bacterial mats which grow in the effluent channels of alkaline hot springs provided an environment suitable for studying natural thermophilic methane producing bacteria. Methane was rapidly produced in cores taken from the meat and appeared to be an end product of decomposition of the algal-bacterial organic matter. Formaldehyde prevented production of methane. Initial methanogenic rate was lower and methanogenesis became exponential when samples were permitted to cool before laboratory incubation. Methanogenesis occurred and methanogenic bacteria were present over a range of 68 to 30 degrees C, with optimum methanogenesis near 45 degrees C. The temperature distribution of methanogenesis in the mat is discussed relative to published results on standing crop, primary production, and decomposition in the thermal gradient. The depth distribution of methanogenesis was similar to that of freshwater sediments, with a zone of intense methanogenesis near the mat surface. Methanogenesis in deeper mat layers was very low or undetectable despite large numbers of viable methanogenic bacteria and could not be stimulated by addition of anoxic source water, sulfide, or a macronutrient solution.