Hyperparathyroidism after renal transplantation. Renal transplantation reduced circulating parathyroid hormone in recipients of renal allografts. Nevertheless, biochemical and histological evidence of mild hyperparathyroidism persisted up to eight years after renal transplantation despite good graft function.


Closure of abdominal wounds by adhesive strips: a clinical trial. In a randomized trial of wound closure in 512 abdominal wounds, wounds were closed with either reinforced Steristrip skin closures or interrupted silk sutures. Comparisons were made of wound pain and discomfort, wound infection, discharge, redness, width, and skin reaction. The causes of peeling of the tapes were assessed. The results showed that tapes were significantly more comfortable and that patients preferred them to sutures (P less than 0.01), but wide scars occurred more often. There was no difference in rates of wound infection and no case of allergy to the tapes was seen. Closure of abdominal wounds by these tapes is a satisfactory procedure that could be used more extensively.


Reticuloendothelial function in renal allograft recipients. The phagocytic capacity of the reticuloendothelial system (R.E.S.) was assessed in patients with chronic renal failure and in renal transplant recipients. R.E.S. phagocytosis was increased in the former group. Soon after transplantation R.E.S. phagocytosis was moderately reduced (through levels were comparable with those of normal controls) but was particularly reduced after high-dose corticosteroid treatment for rejection. In long-term allograft recipients R.E.S. phagocytosis was also depressed though steroid maintenance doses were small.


Survival of infants with unoperated myeloceles. Of the infants with spina bifida referred to a neonatal surgical unit over three years and denied early closure of the myelocele, a significant proportion survived long enough for procedures to drain hydrocephalus to be needed. The key decision in the management of this condition is not whether myeloceles should be closed but whether hydrocephalus should be treated.


Ultrastructural localization of luteinizing hormone-releasing hormone in the median eminence of the rat. The nature of cells in the hypothalamus that produce hypothalamic hypophysiotropic hormones remains unsettled. To investigate this problem electron microscopic immunocytochemistry was performed on thin sections of the median eminence of proestrous rats using antibodies to synthetic luteinizing hormone-releasing hormone (LHRH) and the peroxidase-antiperoxidase (PAP) technique. PAP complexes indicating the presence of LHRH were found over small, homogeneously dense neurosecretory granules 75-90 nm in diameter that occurred in clusters within neurons. Positive staining was more prevalent in the palisade zone in the anterior median eminence than at more posterior levels. LHRH positive granules were not obsereved in neuronal processes in the neurohemal contact zone, but appeared closer to the pericapillary space in the posterior median eminence than at more anterior levels. Occasional groups of LHRH positive granules were also found in the internal layer and hypendymal zone. No staining was observed in tanycytes or glial elements. These results support the hypothesis that hypothalamic hypophysiotropic hormones are produced by neurons and are stored in granules of homogeneous size and density in nerve processes  located in the median eminence in the proximity of the hypophysial portal plexus.


Relationships of intestinal enzymes and serum antitoxin to the pig response to Escherichia coli enterotoxin. The intestinal loop technique was used to evaluate the response of three week old piglets to the heat labile (LT) and the heat stable (ST) enterotoxins produced by Escherichia coli F11(P155). The serum anti-LT activity and the lipase, amylase and trypsin activities in the jejunal lumen of these pigs were determined. Piglets responded independently ti each toxin and no relationship between these responses and serum anti-LT activity or the enzyme activities of the jejunal content could be demonstrated.


Polyserositis in pigs due to generalized Escherichia coli infection. A fibrinous polyserositis syndrome due to generalized Escherichia coli infection in pigs was observed in 13 out of 17 systematically monitored herds. The mortality rate was approximately 0.1% among liveborn pigs. The occurrence was usually sporadic but a minor enzootic was observed in one herd. Most of the affected pigs succumbed during first or second week of life but cases were observed throughout the suckling period. The clinical signs included marked depression, anorexia, rough haircoat, laboured respiration and death in two to five days. Predominant gross pathological lesions were signs of septicaemia and a voluminous, gelatinous and fibrinous exudate in the pleural, the pericardial and the peritoneal cavities. Frequently also a firbinous polyarthritis and a fibrinous pneumonia were present. The majority of the isolated invasive E. coli strains were nonhaemolytic. Serologically 11 different E. coli O groups were encountered. O group most frequently represented was 020. None of the examined E. coli strains belonged to the serogroups which frequently are associated with enteropathogenicity in pigs.


Immunofluorescent cell assay of neonatal calf diarrhea virus. A reliable plaque assay procedure has not yet been described for the neonatal calf diarrhea virus. Therefore, a previously developed immunofluorescent cell counting procedure was adapted to assay this virus. Adsorption of the virus to bovine kidney cells plateaued at 60 minutes. The optimal staining time was between 20 and 24 hours postinfection. Infected cells begun releasing from the coverslips if the cultures were incubated longer than 24 hours. This procedure has proven successful with virus grown in cell culture as well as virus present in fecal samples.


Metabolism of [2-14C]prostaglandin E1 on passage through the pulmonary circulation. A multiple indicator dilution technique was used to study inactivation of [14C]prostaglandin E1 (PGE1) by isolated cat lungs. A bolus containing [2-14C]PGE1, indocyanine green dye and 3HOH was rapidly introduced into the blood entering the pulmonary artery. Sequential samples of the venous effluent were collected and analyzed for 3H, dye, and 14C. The 14C-labelled compounds were separated by thin-layer chromatography, and the quantity of PGE1 and its metabolites contained in each sample was determined (radiochromatogram scanning). Recovery of the dye and 3H was complete within the sampling period. However, only 79% of the injected 14C emerged from the lung within this period, 36% as [14C]PGE1, and 43% as two less polar metabolites. The mean transit times (including connecting tubing) for the unmetabolized [14C]PGE1 and the dye were 9.1 and 8.7 s, respectively. The apparent mean transit times for 14C in the metabolites were considerably longer, 12.4 and 14.3 s. The 3HOH mean transit time was 10.7 s. These data are compatible with an extraluminal site for PGE1 metabolism.


Effective selection of Proteus mirabilis clones producing mirabilicin D-52. From a defective-lysogenic Proteus mirabilis strain we isolated several clones differing in the pattern of their growth on agar plates. Using electron microscopy we have shown some of the selected clones to be efficient in producing mirabilicin D-52 after UV induction, while other clones produced defective mirabilicin polysheaths and polycores. Clones producing polysheaths and polycores can be detected electron microscopically only, since these defective particles are biologically inactive.


Isolation and characterization of a bacteriophage infective for a UDP-galactose-4-epimeraseless mutant of Escherichia coli. A DNA bacteriophage, designated CP13, was isolated against Escherichia coli J5, a UDP-galactose-4-epimeraseless mutant of E. coli 0111:B4. Bacteriophage CP13 appears to be specific for rough bacterial strains. Adsorption studies with E. coli J5 grown with galactose show that the bacteriophage will not adsorb when complete lipopolysaccharide is present in the cell membrane. This indicates that lipopolysaccharide may be directly or indirectly involved with the receptor site for bacteriophage CP13. The bacteriophage DNA has a G + C content of 52%.


Purification and properties of a nuclear polyhedrosis virus from Choristoneura fumiferana. The polyhedral inclusion bodies of a nuclear polyhedrosis virus from the spruce budworm Choristoneura fumiferana were purified by fluorocarbon treatment, sucrose columns, sucrose density gradients, and equilibrium centrifugation. The preparation yields a single and homogeneous band in potassium tartrate gradients at a density of 1.193 g/ml. The virions were released from the polyhedra by alkali treatment and purified by either rate zonal or equilibrium centrifugation in sucrose gradients. The purified virions, which band at a density of 1.265-1.300 g/ml in sucrose, were infectious to the spruce budworm larvae and their mean LD50 was 1.09 +/- 0.1 mug of virus. However, viral nucleocapsids, released by a nonionic detergent, Nonidet P-40, had a density of 1.315 g/ml and were noninfectious by either per os inoculation or intrahemocoelic injection.


[Study of the stability and the degradation of fluorescence in the immunofluorescence technic (FTA-ABS) using pulsed lasers]. The use of two pulsed lasers as excitation sources in the immunofluorescent technique FTA-ABS (fluorescent treponemal antibody absorption) shows that excitation of specimens by continuous or long-duration pulses of light (in the order of a millisecond) degrades the fluorescence in such a way that it is impossible to quantify exactly the fluorescent signal or repeat the analysis. Stability of fluorescence can be achieved by very short excitation pulses (in the order of a microsecond) and this fast fluorescent signal can be detected only by an electronic detection and recording system. With such a system, high precision is obtained by elimination of errors by the human eye.


Repair of heat injury in thymine auxotrophs of Escherichia coli. Heat-induced damage in four strains of bacteria has been studied. It has been shown that the damage is repairable on incubation at 37 degrees C in a medium not supporting growth. The extent of repair is dependent upon the strain of bacterium chosen. Recovery from the damage is prominent in the case of filament-forming bacteria, and in non-filament formers, recovery is not totally absent.


Alpha methyldopahydrazine as an adjunct to levodopa therapy in Parkinson's disease. A double-blind, double-observer study was carried out in twenty-five patients with Parkinson's disease. Alpha methyldopahydrazine in combination with L-dopa was compared to placebo with L-dopa. Combination therapy resulted in a reduction in L-dopa dosage to 1/3 of the amount required during the baseline. There were no side effects attributed directly to the alpha methyldopahydrazine. The overall incidence of side effects in the two groups was similar but the combination therapy significantly reduced the incidence of nausea and vomiting. The limiting factor in the combination therapy was the presence of L-dopa induced dyskinesias.


Cucumber shaped and 35 nm particles in Creutzfeldt-Jakob disease. A 63 year old female with the ataxic form of Creutzfeldt-Jakob disease (CJD) is presented. In addition to amyloid plaques which were not associated with Alzheimer's neurofibrillary tangles, rare profiles similar to those reported in Scrapie were also seen. To our knowledge, these profiles have never been observed in CJD and their presence in this condition adds a further morphologic similarity between the human and animal forms of subacute spongiform "viral" encephalopathies.


Choice of gastric drainage procedures.

Choice of gastric drainage procedures. The need for drainage after truncal or selective vagotomy is well accepted, but there is no agreement on the most suitable type of drainage procedure. A review of the literature, particularly of papers published in the last 3 years, suggests that whereas vagotomy with gastroenterostomy is followed by a relatively high incidence of bile vomiting, vagotomy with pyloroplasty carries a significantly higher risk of recurrent ulceration. The surgeon, therefore, should not hesitate to perform gastroenterostomy if the pyloroduodenum is severely scarred. As pyloroplasty is irreversible, gastroenterostomy is probably the drainage procedure of choice.


Combined cyclophosphamide vincristine, procarbazine, and prednisone (COPP) therapy of malignant lymphoma. Evaluation of 190 patients. One hundred ninety patients who had advanced active Hodgkin's disease, lymphosarcoma, or reticulum cell sarcoma were treated with a combination of cyclophosphamide, vincristine, procarbazine, and prednisone (COPP) given in a cyclical fashion every month. Complete remission was produced in 91 of 138 (66%) patients with Hodgkin's disease and in 39 of 52 (75%) patients with non-Hodgkin's lymphoma (lymphosarcoma and reticulum cell sarcoma). The response rate was higher in patients who completed six cycles of therapy compared to those who completed only three to five cycles: 77% vs. 45%, respectively, in Hodgkin's disease, and 85% vs. 46%, respectively, in non-Hodgkin's lymphoma. The median duration of remission was longer for Hodgkin's disease patients who completed six cycles (30 months vs. 10 months). The median duration of complete remission of non-Hodgkin's lymphoma was 14 months. The response to treatment correlated positively with survival. The median survival time start of COPP treatment for patients with Hodgkin's disease was 7 months for nonresponders, 14 months for those who attained partial remission, and more than 48 months for those who attained complete remission. For patients with non-Hodgkin's lymphoma, the median survival time from start of COPP treatment was 24 months for nonresponders and those who had partial remission, and more than 32 months for those who attained complete remission. Of complete remission responders with Hodgkin's disease, 70% are still alive 84 months after diagnosis, and 63% of the patients witn non-Hodgkin's lymphoma are still alive 48 months after diagnosis.


Clinical comparison of the nitrosoureas. The nitrosourea group of antitumor agents was developed by the Division of Cancer Treatment of the National Cancer Institute. Three nitrosoureas (BCNU, CCNU, MeCCNU) have undergone extensive clinical trials, and two of them (BCNU, CCNU) will soon become commercially available. This paper briefly considers the preclinical development of the nitrosoureas and provides an overview and comparison of the extensive clinical data. Information is given regarding any clinical differences. We discuss general conclusions drawn from the nitrosourea development.


In vitro determination of tritiated thymidine labeling index (LI). Evaluation of a method utilizing hyperbaric oxygen and observations on the LI of human mammary carcinoma. A simple method for incubation of tissue specimens with tritiated thymidine under 3 atm oxygen tension gave an in vitro labeling index (LI) that corresponded closely with LI's determined by injection of tritiated thymidine in vivo.  The LI of tumors was not affected by storage at room temperature for up to 135 minutes. The mean LI for 39 human mammary carcinomas was 3.8, but the distribution was skewed to the right, and the most frequently observed LI's were between 2 and 3. Larger carcinomas had significantly larger LI's than smaller tumors, which suggests that the larger tumors were faster-growing at the time of observation than the smaller tumors. The capacity of the larger tumors to maintain a relatively rapid growth rate may account for their large size. The data suggested, but did not prove, that a high LI was associated with more frequent metastasis to axillary lymph nodes.


Acquired hypertrichosis languiginosa. Report of two new cases and a review of the literature. Hypertrichosis lanuginosa is a pathologic state characterized by an excessive, new growth of fine, fetal hair. Two cases of hypertrichosis languinosa with malignancy (lymphoma and uterine cancer) are presented and added to the 9 in the literature. Lymphoma and uterine cancer are previously unreported as associated with hypertrichosis osis lanuginosa. Review of the 11 cases of hypertrichosis lanuginosa revealed the following characteristics: females were predominant; none was below the 4th decade; all had advanced neoplastic disease; all malignancies except one were of epithelial origin; and there were no demonstrable endocrine abnormalities. Despite an attempt to find etiologic factors in our patients and in the literature, none could be elicited.


Clinical study of the new podophyllotoxin derivative, 4'-demethylepipodophyllotoxin 9-(4,6-o-ethylidene- beta-D-glucopyranoside) (NSC-141540; VP-16-213), in solid tumors. The new semisynthetic epipodophyllotoxin, 4'-demethylepipodophyllotoxin 9-(4,6-o-ethylidene- beta-D-glucopyranoside) (NSC-141540), was tested for antitumor activity against solid tumors and for clinical toxicity in 30 patients. The first two courses were given intravenously (60 mg/m2/day times 5, every 21 days), and subsequent courses were given orally (60-120 mg/m2/day times 5, every 21 days). The drug was subjectively well tolerated but induced considerable leukothrombocytopenia and alopecia. It demonstrated significant activity in oat cell carcinoma of the lung (eight responses out of 11 patients) and ovarian cancer (-our responses out of six patients). NSC-141540 has valuable cytostatic activity against these two tumors and warrants further clinical trials, especially in combination chemotherapy.


4'-demethylepipodophyllotoxin 9-(4,6-o-2-thenylidene-beta-D-glucopyranoside) (NSC-122819; VM-26) and 4'-demethylepipodophyllotoxin 9-(4.6-0-ethylidene-beta-D-glucopyranoside) (NSC-141540; VP-16-213) in childhood cancer: preliminary observations. We evaluated the responses of 39 children with cancer who, after failure to respond to conventional chemotherapeutic agents, received either or both of two epipodophyllotoxins: 4'-demethylepipodophyllotoxin 9-(4,6-o-2-thenylidene-beta-D-glucopyranoside) (NSC-122819) and 4'-demethylepipodophyllotoxin 9-(4,6-o-ethylidene-beta-D-glucopyranoside) (NSC-141540). Seventeen patients has acute lymphocytic leukemia (ALL). 12 had acute nonlymphocytic leukemia (ANLL), and ten had solid tumors. Initially, the patients in each disease category were randomized to receive 50 mg/m2/dose of NSC-122819 intravenously (iv) twice weekly or 75 mg/m2/dose iv of NSC-141540 twice weekly for 4 weeks. Drug dosages and schedules of administration were adjusted during the course of the study. Although objective responses were not detected in the heterogeneous group of solid tumor patients, definite clinical responses were obtained in nine of the 29 patients with acute leukemia. The responses to the two epipodophyllotoxins were noted in patients with ALL as well as in patients with ANLL. Toxic side-effects included nausea, vomiting, diarrhea, fever, alopecia, leukopenia, and thrombocytopenia. These results, the first reported with both NSC-122819 and NSC-141540 in childhood cancer, indicate that the epipodophyllotoxins are well tolerated and may be effective against acute leukemia.


Phase I clinical trial of isophosphamide (NSC-109724). An initial clinical phase I trial of isophosphamide has been carried out at dose levels of 200-10,000 mg/m2 of body surface area using a single-dose, every-3-week schedule. Significant toxicity was not seen at isophosphamide dose levels less than 2900 mg/m2. At higher doses, nausea and vomiting was nearly universal. Hematologic toxicity manifested by leukopenia occurred in 12 of 20 patients treated with doses of 3800-7000 mg/m2. Thrombocytopenia to 100,000 platelets/mm3 was not seen in any patient. Urinary bladder toxicity manifested by hemorrhagic cystitis was seen in 15 of 23 patients treated with doses of 3800-10,000 mg/m2. Hemorrhagic cystitis could be completely prevented by bladder irrigation with N-acetyl-L-cysteine (1% solution, 2000 ml/day). With careful attention to hydration, renal toxicity was largely prevented with blood urea nitrogen elevations to 30 mg/dl in only two of 14 patients receiving isophosphamide doses of 5000-7000 mg/m2. Another side effect was central nervous system toxicity in seven of 17 patients at doses of 5000-10,000 mg/m2. For phase II trials a dose of 5000 mg/m2 is recommended, with careful attention to the state of hydration in the patient and with the knowledge that bladder irrigation may be necessary for the prevention and/or amelioration of bladder toxicity.


Ambulatory monitoring of arrhythmias.

Ambulatory monitoring of arrhythmias. Currently available instrumentation provides the capability of ambulatory electrocardiographic monitoring. A considerable body of literature has developed since the late 1950s which defines an important role for this technique in clinical practice. The use of ambulatory monitoring may ultimately prove as useful in the diagnosis and treatment of occult arrhythmias during activity as monitoring has been during acute phases of myocardial infarction.


Echocardiography in congenital heart disease. It has been demonstrated that echocardiography is a useful and accurate noninvasive technique for the study of congenital cardiovascular diseases. This method provides significant information in that invasive cardiac catheterization and angiocardiography can be planned with greater facility. This is especially important in severely ill babies in whom invasive diagnostic methods are risky. It is particularly attractive in neonates in whom the clinical differentiation of lethal heart disease from septic shock is difficult, since in the latter situation the echographic findings are normal.


Diagnostic value of systolic time intervals in man. The STI offer a quantitative noninvasive measure of left ventricular performance in man. Extensive studies in animals and man have validated the STI. The STI are also sensitive to changes in inotropic state, preload, and afterload, and distinction must be made between the differing effects of acute and chronic alterations upon the STI. When properly performed and interpreted the STI are useful in diagnosis (aortic valve disease, angina pectoris, and pericardial disease), evaluation of the effectiveness of cardiac compensation (coronary artery disease, mitral valve disease, hypertensive heart disease), and evaluation of surgical or pharmacologic interventions. While much investigation is required for a more comprehensive understanding of the clinical application of the STI, the studies summarized in this review support continued use of these measures for the evaluation of left ventricular performance in man.


Coronary arteriography: indications and pitfalls. Selective coronary arteriography has become an unusually useful technique in evaluating patients with known or suspected ischemic heart disease. The contribution of F. Mason Sones in developing the technique and in emphasizing that properly performed studies in experienced hands can be done at an acceptable risk cannot be overemphasized. Although the study can give information only on the anatomical aspects of the disease, it has remarkably broadened ouo understanding of the whole spectrum of coronary arteriosclerosis and ischemic heart disease. This is related to the fact that the method has provided the opportunity to study an extraordinarily large number of patients representing virtually every clinical subset of the disease. The importance of nonanatomical factors, better prognostic information about the disease, and more complete understanding of the hemodynamic ocrrelates and mechanisms of drug action have resulted from investigative studies using coronary arteriographic methods. Because ischemic heart disease is such a complex and variable entity, it is important to stress that coronary arteriography and left ventricular angiography can provide only anatomical information, and that the method has significant but ordinarily recognizable limitations. Some of these limitations are technical and are not important considerations in experienced hands in well-run laboratories. Other problems are inherent in the anatomical complexity of the disease and the coronary circulation. Hence, appropriate emphasis on the details of the patient's history, including risk factors and age, as well as other selected clinical laboratory studiies, such as exercise electrocardiography, are important in assessing the patient's total problem. Because of these factors, the greatest value of coronary arteriography is realized when it is performed as part of a thoughtful, detailed--and highly individualized--evaluation of the patient.


Value of ventriculography in cardiac function and diagnosis. The methods for calculating left ventricular volumes employing biplane angiocardiograms and the calculated parameters of left ventricular mass, pressure-volume diagrams, wall forces, compliance, and abnormally contracting segments are described. Examples of these calculations are given and the contributions to the assessment of cardiac function and diagnosis are discussed. Normal values and the alterations produced by volume overload, pressure overload, myocardial disease, and coronary artery disease are presented.


Radioisotopic measurements of coronary blood flow. This review has presented a critical evaluation of current methods used in measurement of total and regional blood flow. Measurement of total coronary blood flow furnishes little evidence of pathological processes within the coronary vascular system. However, in conjunction with coronary vasodilators, measurement of total coronary blood flow may indicate the presence of coronary artery disease. Difficulties inherent in the determination of regional coronary blood flow lie primarily in defining clearance slopes and in the presence of accidental counts. More promising are methods using scintigraphs obtained with radioactive particles injected into the coronary artery. However, these procedures do not measure flow, only flow distribution. A procedure for measuring regional uptake of positron emitters by coincidence counting has been described; the method possesses definite advantages over other procedures, since it is noninvasive and appears to have good resolution. However, the method is dependent on higher decay density which necessitates the use of nuclides with a short half-life (e.g., 81rubidium).


Myocardial enzymes.

Myocardial enzymes. 1. The use of enzyme analysis has proved considerably valuable in the diagnosis of myocardial infarction. 2. Serial studies of multiple enzymes appear to lend greater specificity and sensitivity to such testing. 3. Creatine phosphokinase appears to be the most useful of the conventional enzymes employed in the diagnosis of myocardial infarction, but limitations due to technical factors and other clinical states causing elevation must be recognized. 4. Current studies to enhance the specificity of enzyme diagnosis in myocardial infarction include the employment of isoenzymes of CPK and LDH. 5. Enzymes appear to afford significant benefit in assessing the prognosis following myocardial infarction and may aid in the selection of therapy.


Transcutaneous Doppler detector in the study of arterial and venous flow patterns. The transcutaneous Doppler flow detector is not presently suited for volume quantitation. However, the arterial flow velocity profile has been established as a valuable procedure for the diagnosis of peripheral arterial disease and assessment of abnormalities of peripheral flow that may result from cardiac arrhythmia or cardiac dysfunction. Distinctive, diagnostic arterial flow patterns in patients with hypertrophic subaortic stenosis and in patients with aortic insufficiency have been described. Occlusive venous disease in the popliteal vein and more proximal vessels can be diagnopsed with an accuracy that justifies the use of the Doppler ultrasound examination as a screening procedure in individuals subject to thrombophlebitis. It is reasonable to anticipate that future work with pulsed Doppler instruments will establish this technique of imaging as a practical clinical method for noninvasive arteriography.


Diagnostic uses of electrical pacing.

Diagnostic uses of electrical pacing. Diagnostic pacing has proven useful for the study of a great variety of clinical problems. Rapid atrial pacing is an excellent means of stressing the heart, particularly in patients with ischemic heart disease. Pacing-induced tachycardia has been used to provoke typical coronary pain and to produce hemodynamic, metabolic, and left ventricular contractile changes in patients with coronary artery disease. Because this heart stress is reproducible, it has also been valuable in assessing response to medical and surgic al therapy in patients with angina. Electrophysiologically, pacing has been used to clarify mechanisms of normal and abnormal function of the sinus node and A-V conduction. The pre-excitation states have been more precisely defined, and the introduction of programmed electrical stimuli into the cardiac cycle has helped elucidate the nature of re-entry supraventricular tachycardias.


Usefulness and limitations of precordial phonocardiography and external pulse recordings. Phonocardiography provides one of a growing list of valuable intermediary studies between physical examination and cardiac catheterization. It not only provides a medium for instruction in physical examination, but also allows one to make certain diagnoses and assess severity of numerous cardiovascular lesions. It is especially valuable in the evaluation of all valvular stenoses, especially aortic stenosis. One can also use phonocardiography for screening and diagnosis of idiopathic hypertrophic subaortic stenosis. It is a helpful adjunct in the study of several congenital abnormalities as well as in the assessment of myocardial function in cardiomyopathies and ischemic heart disease, and may often be decisive in confirming the diagnosis of pericardial constriction.


Followup of implanted pacemakers: an evaluation of surveillance methods. A waveform analysis clinic augmented by telephone transmission of pacemaker interval in the late stages of pacemaker life will yield a considerable amount of information and will permit elective replacement of pacemakers in about 90 per cent of cases. The clinic has an advantage over other surveillance systems in the accuracy of the diagnosis, the identification of abnormalities that do not require pacemaker replacement, and the multiple benefits of a direct doctor-patient relationship. No system of surveillance can be recommended over all others in all circumstances. It is sufficient here to indicate the merits of each system and to allow the various centers to develop according to their own particular needs and desires. There is no objection to telephone monitoring alone as long as one realizes that only about 80 per cent of the problems can be detected and that there will be an irreducible percentage of false negative and false positive diagnoses. The danger of errors of this type is not great, but it does exist and should be avoided if possible. Other methods of pacemaker followup, such as simple examination and an electrocardiogram in a doctor's office or changing the pacemaker on the basis of the manufacturer's prediction, are relatively unsatisfactory. It should be stressed that pacemaker surveillance of some type is essential to satisfactory patient care because it provides for maximum utilization of the pacemaker, for replacement only if and when necessary, for detection of 90 per cent of pacemaker problems, and for protection of the patient against unexpected pacemaker failure.


Intracardiac sound and pressure: right heart events. Toward an ultimate classification of auscultatory events. These observations are presented as a tentative step towards an ultimate classification of auscultatory events based on ICSP studies, chest wall phonocardiography, and auscultatory areas, with continuing clarification or modification by angiography, Doppler techniques, echocardiography, computer usage, and any available, useful technique. The ultimate diagnostic value of ICSP information resides in the feed-back loop wherein this information is used daily at the bedside as part of the understanding and explanation of daily auscultatory phenomena.


Immunohistochemical detection of growth hormone-release inhibiting hormone (somatostatin) in the guinea-pig brain. Utilizing the unlabeled antibody peroxidase-antiperoxidase method, we have studied the distribution of somatostatin (growth hormone release-inhibiting hormone) in the guinea pig brain. An immunohistochemical reaction was found in both internal and external zone of the caudal and median portions of the median eminence. Reaction products were also present in the arcuate nucleus in proximity of the third ventricule. The immunostained elements resembled nerve processes. No cell bodies were stained. A positive reaction was also present in the whole organum vasculosum of the lamina terminalis. In the subfornical and subcommissural organs, somatostatin was observed in the ependymal and subependymal layers and the perivascular areas. In the pineal gland, a positive reaction was also found mainly in the perivascular areas. All the other brain areas were completely negative. These results establish that, in the hypothalamus, somatostatin is mainly concentrated in the median eminence and suggest that periventricular organs can play a role in the regulation of growth hormone secretion.


The ratio of smooth muscle cell volume to cell surface area measured by electron microscopy with corrections for shrinkage. The ratio of cell volume to cell surface area (V/A) has been measured by electron microscopy, for smooth muscle cells of the guinea-pig taenia coli. The extent of shrinkage which occurs during processing for electron microscopy has been estimated using Archimedes' principle. The corrected ratio of V/A is 0.8 mum which is lower than previously published estimates for this tissue. The contribution of the surface vesicles to V/A was not included in the present estimate, but the extra surface area contributed by these organelles would lower V/A even more.


Intracellular localization of actin with fluorescently labelled heavy meromyosin. An improved technique for fluorescent labelling of heavy meromyosin has made it possible to detect on a light microscopic level the cellular sites of actin localization. Rabbit heavy meromyosin (HMM) was labelled with fluorescein isothiocyanate so that the actin binding site was protected during the reaction. The specificity of fluorescent HMM binding to cellular actin was tested by using glycerinated myofibrils. Staining was most intense in the I-Bands, and decreased at the edges of the A-Band, where actin filaments overlap with myosin. No staining occurred in the H-Zones or in the Z-Bands. The fluorescent HMM could be removed by washing with a relaxing solution. Similar sarcomeric patterns were obtained when embryonic chick skeletal and cardiac muscle cells were stained with fluorescent HMM. Localized fluorescent staining was also observed in smooth muscle fibers, axons and growth cones of nerves, acrosomal caps of sperm, cleavage furrows of dividing cells and pseudopods of various motile cells, all of which are known to contain actin. In sessile cells, the actin was found predominantly in fibrous bundles. This pattern of actin localization was altered when the cells underwent cleavage or became motile. The relationship between the intracellular distribution of actin and its function in the cell is discussed.


Interaction of water with egg lecithin in benzene solution. Benzene solutions of purified egg lecithin, with small amounts of water added, have been examined by 60 MGz and 100 MHz NMR spectroscopy, infrared spectrophotometry and phase contrast microscopy. The transverse relaxation times of the water, N-methyl and O--H protons are dependent on water concentration. This dependence changes sharply for the water proton at a level of one water molecule per lecithin monohydrate molecule. These results do not fully agree with those reported by other workers. Four mathematical models are examined which could account for the behaviour of the water protons. Models which assume a constant transverse relaxation time for water protons above a level of one water molecule per lecithin molecule cannot predict the behaviour observed. It is sufficient to assume that water protons above this concentration have a single relaxation time which is a linear function of water concentration. The added water associates primarily with the phosphate in the lecithin head group. Above nine water molecules per lecithin monohydrate molecule free water is present in the system.


Tissue vitamin B-12 assay by a radioisotope dilution technique. A method is described for the measurement of vitamin B-12 (B-12) in solid tissues by radioisotope dilution (RID) assay. The method is a modivication using double extraction of a serum B-12 RID assay which uses chicken serum as the B-12 binder. The method was developed and tested using human and bat liver specimens. Double extraction was shown to be more efficient than single extraction, and resulted in complete release of endogenous liver [57Co] B-12 administered to bats. Results using the RID assay in 16 humans and 17 bat liver specimens were compared with those obtained using the Lactobacillus leichmannii microbiological assay. Correlation was good, but the RID assay gave higher results using the microbiological assay appear to be due to inadequate extraction of B-12 from tissues.


Gonadotrophin hormone releasing tests in women receiving hormonal contraception. Gonadotrophin secretion by the pituitary was tested by i.v. injections of synthetic LH and FSH releasing hormone (LHRH) in five normal women between day 21 and day 25 of the luteal phase of the cycle, in twelve women receiving contraception with i.m. injection of medroxyprogesterone acetate and in eight women taking combined oral contraceptives of different varieties. Treatment with oral contraceptives led to a decrease or even to complete suppression of the response and possibly the reserve capacity of both LH and FSH secretions. Treatment with medroxyprogesterone acetate for several years lowered basal serum LH and FSH as did oral contraceptives but had much less effect on the responses to LRH. In long-term steroid contraception, progestogens alone seem to exert much less deleterious effect on gonadotrophin function than when used in combination with an oestrogen.


The effect of progesterone and FSH and LH response to LHRH in normal women. An LHRH test was performed on twenty-eight regularly menstruating females during follicular phase of their cycles. Twenty-four were then given an intramuscular injection of progesterone in oil and retested with LHRH 20 or 44 h later, the remaining four received no pretreatment and acted as controls. The twelve subjects retested 20 h after the progesterone injection showed marked changes in response. The greatest increase in gonadotrophin release after LHRH was seen when subjects were tested between days 8 and 10 of the menstrual cycle. In contrast, the twelve studied 44 h after receiving the steroid showed no change in release.


[Duration of action of the pyrimethamine-sulfametopyrazine combination in a Plasmodium falciparum endemic zone]. The duration of action of the drug Antemal, a combination of Pyrimethamine and Sulfametopyrazine, was eveluated in Bobo-Dioulasso, Upper Volta, West Africa, and endemic zone for Plasmodium falciparum malaria. The study was held during the season of maximum malaria transmission. 79 persons presenting with an acute attack of malaria were studied; 37 persons received a single dose of chloroquine sulfate (Nivaquine), at a dose of 15 mg./kg.; 42 persons received a single dose of Antemal at a dose of one tablet (75 mg. of Pyrimethamine and 25 mg. of Sulfametopyrazine) per 10 kg. Clinical and parasitological studies of all subjects occurred on days one, two, three, 10, 17, 24 and 31. Only one of 37 (2.7%) subjects on Antemal had a reappearance of trophozoites, occurring on day 17. Eight of 42 (19.0%) patients taking nivaquine had reappearance of trophozoites, observed between day 23 and 31. Gametocytes were observed in eight of 37 (21.6 %) persons on Antemal and in only one of 42 (2.3 %) persons on Nivaquine. These observations suggest an extended duration of protection from Antemal in semi-immune individuals. Nivaquine appeared as a potent inhibitor of gametocytogenesis.


[What was the fate of patients with leprosy during the plague pandemia in the middle ages (1348-1350)]. The author thinks that, if lepra has suddenly decreased in Europe from the 14th century, it is because the most severe cases, i.e. the most contagious ones, disappeared during the hecatombs caused between 1348 and 1350 by the "Black Death", the black plague, which took most often the pulmonary form. The author disproves the opinion of those who think that lepers died from plague. He thinks that lepers' death was secondary to that of the monks who, at this time, cared for these outcases, and thanks to their self-sacrifice permitted these lepers' survival. The monks were more exposed to contagion; obliged by their vocation and by pope's command to help the dyings and to give them sacraments, they were obliged to leave lepers to their fate. Like domestic animals, the latter died of hunger probably, any corpse or carcass being considered as plague victims. Supporting this opinion, the author reports his observations at Madagascar, where no leper of the leper-houses of Madascar center, a plague focus still to-day but very active between 1922 and 1936, contracted plague. On the other hand, experiments with "leprous" rats (Stefansky bacillus) showed a significant resistance of these animals to an experimental plague infection.


A field with a liver measles-mumps-rubella vaccine. Three lots of Lirutrin (measles-mumps-rubella live, attenuated virus vaccine) were evaluated in a double-blind, placebo-controlled clinical study involoving 273 children. The vaccine consisted of a combination of Schwarz strain measles, Jeryl Lynn strain mumps, and Cendehill strain rubella vaccine viruses. The frequency of positive clinical findings was essentially the same in susceptiable vaccinees, immune vaccinees, and placebo recipients; indicating that the observed symptoms were not caused by the vaccine. Antibody assay of paired serum samples revealed that measles, mumps, and rubella seroconverison rates in triple susceptible vaccinees were excellent, ranging from 96 to 98 per cent with all three lots combined. Results of this study show that Lirutrin trivalent vaccine is well tolerated and highly effective.


Cephalexin in the management of bacteriuria. This report evaluates the effectiveness of cephalexin in the treatment of bacteriuria in 93 children. Cephalexin therapy eradicated sensitive organisms in 97 per cent of the cases regardless of recurrence, structural abnormality, or status of renal function. Nevertheless, recurrences with a new, resistant organism occurred significantly in certain patients, expecially those with major anatomic abnormalities, during a six-week follow-up period. The incidence of drug reactions was low.


Comparison of cardiac effects of timolol and propranolol. The cardiac effects of the beta-adrenergic blocking agent, timolol, were compared to those of propranolol after intravenous administration in 6 healthy male subjects. The effects of timolol and propranolol on maximal exercise-induced tachycardia were measured. Timolol was about ten times as potent as propranolol in antagonizing exercise-induced tachycardia. Dose-response curves to intravenous infusions of isoproterenol were obtained after three doses of each beta-antagonist. Changes in myocardial contractility were assessed by cardiac systolic time intervals and were compared to the simultaneous changes in heart rate elicited by isoproterenol. For the 6 subjects, the mean potency ratios of timolol to propranolol as an antagonist of the chronotropic and inotropic effects of isoproterenol were 13.8 (+/-0.8) and 12.7 (+/-1.0), respectively. Neither timolol nor propranolol acted more selectively on beta-receptors affecting heart rate than on those influencing contractility.


Effects of marihuana combined with secobarbital. Twelve male volunteers smoked a marihuana cigarette prepared to deliver 0 or 25 mug/kg tetrahydrocannabinol (THC) 50 min after ingesting a capsule containing either placebo or 150 mg/70 kg sodium secobarbital. Drugs were administered in a double-blind manner, and all treatments were assigned to each subject in a randomized complete block design. Objective and subjective tests designed to measure mental and motor performance indicated that marihuana impaired stability, hand-eye coordination, and mental performance. Secobarbital affected motor performance, manual coordination, and mental performance. In combination, marihuana and secobarbital had an additive effect on subjective responses and impairment in certain psychomotor performance tests.


Triazolam in insomniac family practice patients. Triazolam, 0.5 mg, a benzodiazepine with hypnotic properties, was compared to secobarbital, 100 mg, and placebo in a 1-wk study conducted with 100 insomniac family practice patients. Considerable sensitivity to differential treatment effects was demonstrated for these family practice patients as well as for a research methodology that combines a crossover design, permitting preference ratings, with a between-patient design. In almost all sleep parameters, assessed with a variety of subjective techniques, triazolam and secobarbital were shown to be significantly more effective than placebo. Triazolam was consistently and often significantly indicated to be a more effective hypnotic, particularly for reducing nocturnal awakening, than secobarbital. Analysis of self-report emotional distress data revealed that present insomniac patients were slightly more emotionally symptomatic than other nonpsychiatric populations. Triazolam was followed by the greatest and secobarbital the least relief of emotional symptoms and triazolam emerged as an especially effective hypnotic for initially more depressed insomniac patients. Present findings suggest that type and degree of emotional symptomatology may affect the response of insomniac patients to hypnotics.


Penfluridol steady-state kinetics in psychiatric patients. Twenty-two hospitalized schizophrenic patients, participating in a large-scale phase II double-blind dose-effect study (30, 60, and 120 mg weekly) of penfluridol, a new diphenylbutylpiperidine neuroleptic, were maintained on a regular dosage regimen for 13 wk. Several blood samples were taken during the last dosage interval. Results show that the peak concentration develops within 12 hr after the last dose. A rapid decline, probably due to tissue re-equilibration, then occurs and is followed by a much slower falloff. Detectable concentrations 168 hr after administration are consistent with the long duration of action of penfluridol. Statistically significant differences between doses were found in the analysis of variance of plasma concentrations at all sampling times and in mean steady-state plasm concentrations. Wide differences in plasma concentrations were noted in patients receiving the same absolute dose, but a good relationship was defined between mean steady-state concentration and the dose expressed as mg per either kg of body weight or square meter of body surface area.


Bioavailability of dexamethasone. II. Dexamethasone phosphate. Plasma levels of dexamethasone phosphate (DP) and dexamethasone free alcohol (DA) were determined by a modification of existing radioimmunoassay methodology following intravenous administration of DP in man. Areas under DA plasma profiles were a linear function of DP dosage over the 40-fold range 0.05 to 2.0 mg/kg, and, by comparison with values obtained after DA was intravenously administered, indicated an overall conversion of DP to DA of 90%. The first-order rate constant for the conversion, 4.03 hr-1, was approximately 25 times that for hydrolysis in whole blood incubated in vitro. This relationship as well as disposition kinetics suggested that the major component of DP hydrolysis occurs within highly perfused organ(s) comprising the central kinetic compartment. Eighteen subjects were studied in a crossover experiment, and no significant differences were observed in best-fit parameters for the 4 mg/ml parenteral solution of DP in current use and an experimental high potency preparation of 24 mg/ml.


Suppression of cortisol by a progestational steroid, melengestrol. Melengestrol, a steroid with progestational activity but with a structure that does not resemble that of cortisol, suppresses plasma cortisol in humans with a potency 1/40th that of dexamethasone. The 6alpha-methyl and 17alpha-acetoxy substituents and the 6,7 double bond of melengestrol acetate are known to slow the metabolism of similar steroids. Insertion of a 6alpha-methyl group markedly increases the glucocorticoid activity of 17alpha-OH-progesterone. The glucocorticoid activity of melengestrol is presumably attributable to the large dose administered in our study, its slow metabolism and limitations of the specificity of glucocorticoid tissue receptors.


Correlation of plateau serum salicylate level with rate of salicylate metabolism. The range of plateau serum salicylate concentrations was 4.4 to 33 mg/100 ml in patients with rheumatoid arthritis after they were treated with 50 mg/kg of aspirin daily for 5 days. Individual plateau serum levels correlated better with urinary excretion rates of the metabolite, salicylurate (whose maximum production is capacity-limited), than with total urinary excretion of salicylates. These observations suggest that large intersubject variations in plateau serum salicylate levels are determined, at least in part, by similar differences in the maximum rates of capacity-limited metabolic reactions. For optimal therapeutic responses, individualization of aspirin dosage by following serum salicylate levels is recommended.


Pharmacokinetics of indomethacin.

Pharmacokinetics of indomethacin. Plasma concentrations of indomethacin have been studied in 5 healthy volunteers after single and multiple doses (25 mg intravenously [iv], 25, 50, and 100 mg orally, 100 mg rectally, and 25 mg three times daily [tid]. In 8 other normal subjects and in 5 patients a 50-mg oral dose of indomethacin was given and the indomethacin concentration was followed from 8 to 32 hr after dosing. All analyses were carried out using a new mass fragmentographic method. After oral and rectal doses the plasma decay of indomethacin was biphasic, and the data were interpreted according to a 2-compartment open model. The half-life of the beta-phase varied between 2.6 and 11.2 hr. The volume of distribution ranged from 0.34 to 1.57 L/kg and the plasma clearance from 0.044 to 0.109 L/kg/hr. There was no evidence of dose-dependent elimination. Indomethacin was rapidly and well absorbed after oral dosing with peak plasma concentrations within 2 hr. Comparison with the area under the curve (AUC) after iv dosing indicated complete bioavailability. The AUC after rectal dosing indicated complete bioavailability, but the rate of absorption was slower than after oral administration. Indomethacin, 25 mg three times daily, was also given for 9 days to the same normal subjects; equilibrium concentrations obtained did not differ significantly (p greater than 0.1) from those predicted from single-dose data in the 5 subjects.


Relative potency of prorenoate and spironolactone in normal man. The potency of single doses of a new aldosterone antagonist, prorenoate, in reversing the renal effects of the synthetic mineralocorticoid fludrocortisone was compared to that of spironolactone in a double-blind balanced crossover study in 12 healthy subjects. The potency of prorenoate potassium as related to elevation of the urinary log 10 10 Na/K ratio (2.69:1) and as related to potassium retention (3.75:1) was significantly higher than that of spironolactone. Prorenoate produced greater natriuresis (1.64:1) but the difference was not significant. There was evidence for a qualitative difference between spironolactone and prorenoate; the latter significantly more potent in retaining potassium than in increasing sodium excretion. The simple methodology described is based on standard bioassay principles, yielded a valid and sensitive comparison of the two drugs, and should prove useful in the evaluation of other aldosterone antagonists.


Temporal variations in acetaminophen and phenacetin half-life in man. Acetaminophen (APAP) and phenacetin mean plasma half-lives were approximately 15% longer in normal male volunteers at 6 A.M. than at 2 P.M. as determined after oral administration of each drug at 6 A.M. and 2 P.M. Concentrations of plasma 11-hydroxycorticoids (11-OHCS) in these volunteers were approximately 42% higher at 6 A.M. than at 2 P.M. The mean apparent volume of distribution (aVd) of APAP decreased by approximately 13% from 6 A.M. to 2 P.M., whereas the mean metabolic clearance rate (MCR) of APAP did not change significantly. Neither the mean aVd nor the mean MCR of phenacetin changed significantly from 6 A.M. to 2 P.M. Measurement of urinary metabolites showed no alteration in APAP glucuronidation in the 8-hr period following APAP administration at 6 A.M. or 2 P.M., but indicated that after phenacetin administration 10% more of the dose was oxidatively metabolized to APAP during a 24-hr period beginning at 2 P.M. than at 6 A.M. Within each subject, plasma acetaminophen or phenacetin half-life at 2 P.M. or 6 A.M. was highly reproducible, but large interindividual variations occurred in the extent of temporal variation during this period.


Bioavailability and single-dose pharmacokinetics of intramuscular phenytoin. Comparison of phenytoin plasma concentrations in an intravenous and intramuscular crossover study in 12 healthy ambulant, male subjects indicates that phenytoin administered intramuscularly is absorbed over a period of approximately five days. A model simulating precipitation and redissolution of the drug at the injection site has been shown to satisfactorily fit observed plasma concentration data following intramuscular administration. It is proposed that this model will be useful in the selection of an appropriate dosing regimen in situations in which intramuscular administration of phenytoin is indicated.


Combination 6-mercaptopurine-adriamycin in refractory adult acute leukemia. Remission induction therapy with 6MP and adriamycin in combination was administered to 19 adult leukemic patients refractory to previous therapy. Eight patients also received vincristine and prednisone. Thirteen patients had acute myelogenous leukemia, 3 undifferentiated leukemia, and 3 blastic transformation of chronic myelogenous leukemia. Four patients achieved remission but in only 2 were the remissions complete. Eleven patients failed to respond. Ten of the 19 patients developed unexpected severe liver toxicity manifested by a clinical picture of cholestasis (in the majority) or ascending cholangitis (in 2 patients). In the postmortem examination of 8 patients there was cholestasis and mild to severe hepatocellular damage in all.


Effects of ticlopidine, a new platelet aggregation inhibitor in man. Ticlopidine is a new platelet aggregation inhibitor. The effect of this drug was studied on 55 subjects, healthy volunteers and hospitalized patients. The action requires 24 to 48 hr to appear, and lasts more than 3 days. A dose-effect relationship was studied with oral daily doses ranging from 250 to 1,000 mg during 1 wk; it showed a 50% inhibition on adenosine diphosphate (ADP)-induced aggregation at 2 muM concentration on an oral daily dose of 450 mg. No action was found on collagen-induced aggregation, and a mild effect was observed on platelet adhesiveness. Clinical tolerance was assessed in patients given ticlopidine in oral doses up to 500 mg/day during several weeks, showing no overt side effects and no change in the safety parameters.


Galactose-specific messenger ribonucleic acid contents in Escherichia coli: effect of inducer, gene dosage and galactose genotype. Galactose specific mRNA (gal-mRNA) and galactokinase were measured in strains of E.coli with varying numbers of copies of the galactose operon. While the fucose induction the amount of gal mRNA has been found to be proportional to the content of galactokinase and to the gene frequency, with galactose induction this was not the case. It is suggested that this is a result of the metabolism of galactose leading to catabolite repression. The amounts of gal-mRNA and galactokinase were also measured in a series of polar mutants. With increasing polarity, there was a greater effect on enzyme content than on gal-mRNA. This suggests that the effect of polarity on RNA is the result of degradation after synthesis rather than prevention of transcription. A method of correlating hybridisation data with the genetic map is described.


Idiopathic pulmonary hemosiderosis. Electron microscopic, immunofluorescent, and iron kinetic studies. The clinical course of a 37-year-old white man with idiopathic pulmonary hemosiderosis is presented. This patient is unusual in that he has had repeated exacerbations and remissions over a period of seven years and remains currently in spontaneous remission with no therapy. Routine sections of the lung biopsy revealed characteristec findings. Immunofluorescence staining of the lung was negative, and electron microscopic studies showed only nonspecific findings. While in remission, 51chromium-labelled red-blood-cell survival studies and 59iron kinetic studies were performed; the results were normal.


[Fungal infections after renal transplantation (author's transl)]. 21 of 41 patients developed clinically manifest or systemic Candida albicans infection 1-36 months after renal transplantation. Asymptomatic candiduria was diagnosed in all patients even before the onset of clinical symptoms. Fungal stomatitis was the most frequent clinical sign, followed by mycotic changes in the respiratory, genito-urinary (vaginitis) and gastro-intestinal tract. In five cases intrahepatic biliary stasis was diagnosed in the course of a Candida albicans septicaemia. In 12 patients with renal transplants it was possible, by treatment with nystatin, clotrimazole, flucytosine, miconazole and amphotericine B to control a generalized or clinically manifest Candida albicans infection. Three died of the septicaemia or meningoencephalitis, six as the result of bacterial superinfections. Inspection of the mouth is an important means of early diagnosing fungal infections. Antimycotic treatment should be started if fungal cultures from urine are repeatedly positive even if the clinical findings are still negative.


[Indirect immunofluorescence in the serological diagnosis of chronic pyelonephritis (comparison with indirect haemagglutination and the Widal reaction (author's transl)]. Using indirect immunofluorescence, o-antibodies against the homologous causative organism were determined in 119 adults with chronic pyelonephritis, during a one to two-and-a-half year period. Humoral antibodies were determined in the same group of patients with the Widal reaction and indirect haemagglutination. The results were compared with those in a group of adults without renal disease, using the same serological reactions. In adults with chronic pyelonephritis the antibody titre (by immunofluorescence) was above normal limits (as obtained in the healthy group) in 63.1%. The corresponding results for the Widal reaction and indirect haemagglutination reaction were 16.5% and 12, respectively. Indirect immunofluorescence is thus clearly better than the other two serological methods in the diagnosis of chronic pyelonephritis.


[Effects of bridge parts on the gingiva]. Over the past few years, preparation and insertion of a dental bridges have been considerably modified and rationalized due to new methods and techniques. The former requirements the shape of pontics hat to meet are no longer fully valid. The behavior of the various materials (metals, resins, ceramics) in the mouth and especially towards the gingiva has been tested sufficiently. Knowledge regarding the functional conditions (flushing of the gingiva underneath bridges, turgor, abutment mobility, pulsation) has considerably increased in the past few years. Therefore recommendations regarding the shaping of pontics can be formulated that meet the anatomic, physiologic, and hygienic conditions as well as the esthetic wishes of the patients.


[Clinical study on the contact between the partial denture and the alveolar process]. 53 clinically prepared bridges were examined with regard to the resting position of the bridge body on the alveolar ridge, before they were finally cemented. It was to be tested whether the ideal requirements of punctate or linear pressure-less resting was met and if not, how big the portion of the base resting on the gingiva was as compared to the total base. All bridge bodies were resting on the alveolar ridge without exerting pressure but with a more or less broad base. In 42 out of the 66 examined cases, the bridge body was in a 50 to 100% contact with the mucosa.


Antibacterial drugs today. I.

Antibacterial drugs today. I. Since the development of the sulphonamides in the 1930s and the subsequent development of antibiotics from the 1940s onwards, there have now been many drugs developed which are capable of chemotherapeutic activity in a patient infected by a susceptible micro-organism. This review is concerned with precise descriptions of important groups of antimicrobial drugs, with emphasis being placed on the more recently developed drugs. With each group of drugs the pharmacology, major therapeutic indications, dosages and adverse reactions are discussed. Part I of the article discusses the sulphonamides, the natural and semi-synthetic penicillins, cotrimoxazole, chloramphenicol, tetracyclines, the macrolides, lincomycin and clindamycin, fusidic acid, and the urinary antiseptics. The place of each in therapy is defined.


[Chemical analysis of methacrylate plastics]. It was the object of this study to find quick but exact methods for determining the components of quickly setting methacrylate materials for dentures, dental fillings (PMMA) and for bone surgery. Furthermore, lower-molecular components still being present in the hardened resin were tested. By measuring refraction index and by infrared spectrum and gas-chromatographical analyses the composition of the liquid is obtained. Dimethyl-p-toluidine, hydrochinon and cross-linking agents were determined spectrophotometrically. Filling agents, pigments, plasticizers and soluble components of the powder were determined gravimetrically. The presence of polystyrol is established by infrared analysis, that of benzoyl peroxide by spectroscopic analysis. As to the hardened material, the molecular weight is determined by viscosity measurements and the molecular weight distribution by gel permeability measurements. Residual monomer is found by gas chromatography.


[Findings on the functional planning of dentures]. Analysis of over 20,000 prosthetic treatments carried out in the area of one association of dentists working under the compulsory public health insurance plan shows that prior to the conclusion of the new financial agreements on prosthetics, a treatment plan based on the findings and aiming at appropriate functional rehabilitation had been prepared in half of all the cases only.


[Follow-up studies on model cast prostheses after 4 years wear]. Over a period of 4-1/2 years, patients having model cast dentures that had been inserted in the dental office were checked and submitted to follow-ups. It became evident that the socalled pre-prosthetical measures had been performed in a non-satisfying manner. In 69% of the patients, teeth had been extracted directly before inserting the model cast denture. As a result thereof, a majority of the dentures was sagging after a relatively short time and 70% of the dentures revealed non-occlusion in the final follow-up. 47% of the dentures had to be modified because of necessary tooth extractions, thereby reducing the original number of abutment teeth by 19%. About a third of the inserted model cast dentures showed gross deficiences, the percentage of socalled "collar" constructions was relatively high.


[A data storage system in computer dialog for dental prosthetics]. It is reported on a data processing system with computer dialogue for the "standardized sheet of findings". The computer-readable form, improved error control, and optimum evaluation possibilities are emphasized as special advantages. Simple handling and optimum data protection permit to have this system operated by trained laymen.


[Shape of the denture base and self-cleaning]. It is reported on the relationship between the extent of the gap between teeth and denture and the formation of plaque.


[Measurement of the pressure in dental casting]. The tests showed that the pressure exerted on the tooth stump and the surrounding tissue is determined by the consistency of the impression material, the amount escaping from the impression tray, the adaptation pressure and adaptation speed. The original consistency of the impression material without exposure to a catalyst is an especially important factor. If the material has a flow limit (e.g. Optosil with or without catalyst) it is exerting pressure in any case and this pressure continues even after setting. Impression materials without flow limit (e.g. Silaplast without catalyst) produce practically no pressure. Only by the activity of the catalyst a flow limit develops and thus pressure is produced.


[Development of an internal cooling mechanism for surgical drills]. An interior liquid cooling method was developed for surgical burs and tested in animal experiments as well as during the treatment of patients. The method ensures excellent cooling of the bone during surgical treatment.


[Immediate prosthetic management of surgically treated maxillary lesions]. In accordance with a method previously published - in which undercut areas in the region of resection are utilized for retaining the denture - a modified method is presented permitting immediate prosthetical care for operated maxillary defects despite fresh wound surfaces and constrictio maxillarum.


[Jaw metastasis of sympathicoblastoma].

[Jaw metastasis of sympathicoblastoma]. Using the example of a sympathicoblastoma metastasizing into the jaw, the symptomatology of this rare location of metastases is outlined. Jaw metastases of sympathicoblastomas occur in greater numbers only in children in the age of 2.5 to 5 years. Osteolytic jaw defects and unexplainable loosening of permanent molars in children should give rise to detailed examination with regard to the possible existence of a metastasizing malignant tumor (especially neuroblastoma). Despite a solitary metastasis, early diagnosis might have a decisive influence on the otherwise lethal course of the disease.


[The decalcification of teeth for histological studies by means of ultrasonics]. In order to accelerate decalcification of hard tissues for histological examinations, the additional application of ultrasonics is sometimes recommended. Comparative studies show that decalcification is not acclerated by ultrasonics.


[Clinical studies on a sodium monofluorophosphate toothpaste in school children]. Random tests made in school children of the Ludwigsburg district showed that after 3 years of uncontrolled use, the number of new DMF surfaces is smaller in children using Na2PO3F toothpaste and regularly cleaning their teeth than in the corresponding placebo groups. The caries-inhibiting effect was statistically significant (significance level p=0.05%). The increase in caries impact in school children regularly but insufficiently cleaning their teeth was also significant in the placebo groups.


[Quantitative determination of the gingival sulcus fluid by means of microcapillaries]. Evaluation of the quantity and quality of crevicular fluid has become increasingly important in the past few years. Amount and composition of the gingival exudate reflects the physical condition of the gingival margin. For drawing off the gingival fluid primarily filter paper stripes are recommended. Some authors use microcapillaries made of glass. For facilitating measurements on the fluid a special method is described using standardized glass pipettes for collecting the gingival exudate.


[Statistical analysis of the activity of loxapine and thioridazine in a double-blind study]. 49 patients have been treated for 12 weeks with loxapine and thioridazine in a double-blind study. The evaluation was carried out with a covariance analysis with B.P.R.S. and NOSIE as bases and a variance analysis concerning the general clinical improvement. With 36 schizophrenics, the two treatments have shown significant and similar general improvement as early as the second week, and this in particular with all the factors and most of the items of the B.P.R.S. with 13 psychotic not schizophrenic patients, the covariance analysis showed that the results (improvement of all the factors, with most of the items and in the total score of the B.P.R.S.), while comparable, were slightly in favour of loxapine for the item "disorientation", for "disturbance of thought", and "excitement-disorientation", for the final score of B.P.R.S., for the general and clinical improvement and for the alteration of the initial degree of severity. The analysis of the NOSIE showed a significant improvement which is similar for both treatments.


Age-related changes in pituitary responsiveness to LHRH in the female rat. Serum LH changes in response to LH-releasing hormone (LHRH) injection were measured in young (4-6 month-old) proestrous, estrous, and second-day-diestrous rats and in aged(23-30-month-old) constant estrous and irregular pseudopregnant (prolonged diestrus) female Long-Evans rats. Serum LH was measured by radioimmunoassay in serial blood samples taken before and at 15, 30 and 60 min after injection of 0, 5, 50 or 500 ng of LHRH. Serum LH also was assayed in similar groups of rats acutely pretreated with either 20 mug of estradiol benzoate (EB) or 5 mg of progesterone. Aged rats showed a smaller increase in serum LH following LHRH injection than the young groups. Within the young groups, the magnitude of response was greater in proestrous and estrous rats than in the diestrous animals. Pretreatment with EB resulted in increased serum LH after LHRH injection in young estrous and diestrous rats and in aged constant estrous rats, but did not alter serum LH levels in the aged pseudopregnant rats. Although the inccrease in serum LH after LHRH injection was greater in all young groups given progesterone pretreatment, progesterone pretreatment did not affect LHRH responsiveness in either of the aged groups. These results suggest that with aging, the pituitary becomes less capable of relasing LH in response to acute LHRH stimulation, and that the pituitaries of aged rats are less responsive to gonadal steroid sensitization to LHRH stimulation.


Immunoreactive gonadotropin-releasing hormone (Gn-RH) during maturation in the rat: Ontogeny of regional hypothalamic differences. The developmental appearance of immunoreactive gonandotropin releasing hormone (Gn-RH) was measured by radioimmunoassay in male and female rats from the 12th day of gestation to adulthood. Gn-RH content of the whole hypothalamus of both sexes increased from birth to 21 days of age. By the 28th day, Gn-RH content in females had approximately reached adult levels, while that in males continued to increase. Adult male rats exhibited significantly higher levels than adult females. The ontogeny of the regional differences previously observed in cycling female rats (4) was also studied. Regional analysis of Gn-RH development was characterized in the anterior hypothalamus by the rapid attainment of adult levels by day 7. In striking contrast, in the mid-hypothalamic region, Gn-RH content increased gradually, rising dramatically just prior to vaginal opening. The developmental pattern of Gn-RH content is consistent with the maturation of those hypothalamic structures concerned with synthesis, transport and storage of Gn-RH. The regional patterns observed may thus represent sequential maturation of the neural pathways involved.


Radioimmunoassay for luteinizing hormone releasing hormone in plasma. A sensitive and specific double antibody radioimmunoassay has been developed capable of measuring LH-RH in extracted human plasma. Thyrotropin releasing hormone, lysine vasopressin and most of LH-RH analogues did not appear to affect the assay. Hypothalamic extract and some of the LH-RH analogues produced displacement curves which were parallel to that obtained with the synthetic LH-RH. Sensitivity of the radioimmunoassay was about 3 pg per assay tube. The coefficient of variation of intraassay was 6.4%, while that of interassay was 9.6%. Exogenous LH-RH could be quantitatively extracted by acidic ethanol when varying amounts of synthetic LH-RH were added to plasma. Immunoreactivity of LH-RH was preserved in plasma until 2 hr in the cold and gradually reduced thereafter. The plasma levels in LH-RH were 20 pg/ml or less in normal adults and not detectable in children. The aged males over 60 yr and postmenopausal women showed a tendency to have higher levels of plasma LH-RH. Plasma LH-RH level was significantly higher in midcycle than in follicular and luteal stages. The disappearance rate of LH-RH from the circulation after intravenous injection could be represented as half times of 4-6 min. Between 0.2-0.4% of the injected dose was excreted into urine within 1 hr. These results indicate that the determination of LH-RH might be a useful tool for elucidating hypothalamic-pituitary-gonad interactions.


[Studies on long-term irradiated rats using clomiphenedihydrogen citrate, LH and LH-RH]. The influence of clomiphene, LH and LH-RH on vaginal cycle and ovarian function in mature rats, which had been exposed to continuous light in order to block the cyclic sexual centre, was examined by different doses. While ovulation was obtained by administration of LH and LH-RH, clomiphene showed no effect. It may be assumed that the central mode of action of the "ovulation inducing effect" of clomiphene is mediated by stimulation of the cyclic sexual centre in the anterior hypothalamus.


Ultrastructure of rat pituitary gonadotrophs after injection of synthetic luteinizing hormone releasing factor (LRF). The effects of intracarotid injection of synthetic luteinizing hormone releasing factor (LRF) on the ultrastructure of pituitary gonadotrophs are reported. Chronically ovariectomized rats of the Sprague-Dawley strain pretreated with oestradiol and progesterone were sacrificed at zero time and at 30, 120 min after injection of 1 mug of synthetic LRF. A careful observation was made for evidence of granule extrusion from gonadotrophs following intracarotid injection of LRF, but no signs of granule extrusion were demonstrated. However, granule migration to the periphery of the cell was observed 30 min after LRF injection and the distribution of secretory granules recovered 2 hours after injection. The result of ultrastructural observations suggests that LRF plays an important role in releasing and synthesizing gonadotrophins in pituitary gonadotrophs. Further investigations should elucidate more clearly the morphologic aspect of mode of LRF action in pituitary gonadotrophs.


Lead in the environment - origins, pathways and sinks. 1. Lead is a natural constituent of the environment. 2. In many urban areas, the principal source of elevated lead in soils is the weathering of paint on houses. 3. Burning of lead in gasoline is the main source of lead in air in many areas. This lead is removed by sedimentation and in rainfall and snowfall. 4. Soil and sediments are the ultimate sinks for lead. 5. Man receives an average of about 300 mug of lead per day in his food, but the range is between 100 and 400 mug. 6. The natural concentration of lead in food resulting from the natural lead content of soil is a few tenths of a microgram per gram of wet plant material. 7. Present concentrations of lead in air do not measurably increase the lead content of the edible portion of most plants. 8. A several-fold increase in lead in soil does not measurably change the concentration of lead in plants. 9. Leafy portions of plants near busy highways contain higher concentrations of lead. 10. Rainwater does not appear to be a significant source of lead in crops.


Fluorescence studies on the interaction between yeast seryl-tRNA synthetase and its substrates. Substrate-induced variations in the native fluorescence of seryl-tRNA synthetase from yeast have been used to evaluate the binding equilibria with its ligands. Binding of L-serine to the enzyme can be detected by equilibrium dialysis but not by fluorescence quenching. Hence, in contrast to ATP and tRNA(Ser), L-serine does not induce any fluorescence-sensitive conformational change of the synthetase. A comparison of the binding constants for ATP (2 X10(4) M-1) and seryl adenylate (1 x10(6) M-1) indicates that the activation reaction is mainly driven by the higher affinity of seryl adenylate to the enzyme. tRNA(Ser) and seryl-tRNA(Ser) though causing rather different maximal fluorescence quenching are bound to the enzyme with similar stoichiometry and association constant. The implications of this result are discussed with respect to the mechanism of the aminoacylation reaction. It is also shown that the enzyme clearly is capable of discriminating L-serine from other amino acids, ATP from other nucleotidetriphosphates and AMP, and tRNA(SER) from other tRNA species in the binding processes. The spectral properties, the effects of outside quenchers and the fluorescence decay times of the free enzyme and the enzyme-substrate complexes are discussed with respect to the intercalation hypothesis of Hélène.


A study of codon-dependent binding of aminoacyl-tRNA with the ribosomal 30-S subparticle of Escherichia coli. Determination of the active-particle fraction and binding constants in different media. Titration of isolated Escherichia coli ribosomal 30-S particles with [14C]phenylalanyl-tRNA in the presence of poly(uridylic acid) was used for a quantitative assay of codon-dependent binding of aminoacyl-tRNA with the small ribosomal subparticle. The technique has allowed the estimation both of the fraction of "active" 30-S subparticles capable of forming the 30-S - poly(U) - phenylalanyl-tRNA complexes and the equilibrium constants of phenylalanyl-tRNA binding in different media. Heterogeneity of the ternary complexes formed has been revealed: at least two classes of complexes differing in stability have been observed. The stability of the 30-S - poly(U) - phenylalanyl-tRNA complexes has been shown to decrease with the lowering of the Mg2+ concentration, the increase of K+ concentration and the addition of urea. The stability of the complexes increases with the increase of Mg2+ concentration, with the addition of ethanol and decrease of temperature. It is demonstrated that the fraction of actively binding 30-S particles also varies in different medium conditions; it decreases with the increase of ionic strength (K+) and with the addition of urea, and increases with the increase of Mg2+ concentration and addition of ethanol.


The mode of action of pleuromutilin derivatives. Location and properties of the pleuromutilin binding site on Escherichia coli ribosomes. Using equilibrium dialysis techniques it could be demonstrated that (a) the pleuromutilin derivative 14-deoxy-14[(2-diethylaminoethyl)-mercaptoacetoxy] dihydromutilin HCl binds to one site per ribosome specifically, (b) the binding constant is 1.3 times 10(7) M(-1) and (c) chloramphenicol and puromycin compete with binding of the pleuromutilin derivative. Similarly the nucleotides CpA and CpCpA also displace the unsaturated derivative of the above-mentioned pleuromutilin compound. These findings suggest that the ribosomal binding site for pleuromutilin overlaps with that for chloramphenicol and analogs of the 3'-terminus of a tRNA, like puromycin or the nucleotides CpA and CpCpA.


The mechanism of template activation by exonuclease V. In crude extracts from Escherichia coli cells the ATP-dependent exonuclease V was found to be most active in converting double-stranded DNA into a suitable template for DNA polymerase. This phenomenon was studied in some detail with isolated exonuclease V and T7 DNA polymerase. We found that, at ATP concentrations arount 1 mM, the exonuclease produces a broad spectrum of DNA fragments. One class of fragments is largely single stranded with hydrogen-bonded small primer sequences. These structures allow the synthesis of remarkably homogeneous polynucleotide strands by T7 DNA polymerase.


Molecular morphology of ribosomes. Iodination of Escherichia coli ribosomal proteins with solid-state lactoperoxidase. Using either soluble or solid-state lactoperoxidase, a comparison was made between the enzymic iodination of ribosomal proteins iodinated as 30-S and 50-S subunits or as 70-S monosomes. Proteins S7, S11 and S12 of the 30-S subunit and proteins L2, L11, L26 and L28 of the 50-S subunit were labelled to a greater extent in isolated particles than in the 70-S ribosome. In contrast, proteins S4, S19 and S20 were labelled to a lesser extent in the isolated subunit. No significant differences were observed in the iodination patterns of ribosomes iodinated in the presence of soluble lactoperoxidase and those iodinated in the presence of lactoperoxidase bound to Sepharose 4B. It is suggested that the 30-S subunit undergoes a conformational change during its association with the 50-S subunit to form a 70-S monosome. Implications from results obtained with solid-state lactoperoxidase-catalyzed iodination of ribosomal proteins are also discussed.


Covalent attachment of DNA to agarose. Improved synthesis and use in affinity chromatography. DNA has been covalently linked to insoluble matrices of agarose (Sepharose) in high yield using cyanogen bromide activation. Both double-stranded and single-stranded DNA have been coupled with yields up to 225 nmol/mg dry weight Sepharose or 3-8 mumol nucleotide phosphate/ml bed volume. The DNA-Sepharose has been used for (a) the affinity chromatography of various enzymes (Escherichia coli DNA polymerase I and RNA polymerase) from crude extracts or after initial purification steps, resulting in high yields and degrees of purification, and for (b) nucleic acid hybridization. The DNA-Sepharose is stable to high temperature, prolonged storage, and in the case of single-stranded DNA, can be washed with NaOH to destroy nuclease activity and to release any digested oligonucleotides or mononucleotides.


Sterol biosynthesis in yeast. 3-Hydorxy-3-methylglutaryl-Coenzyme A reductase as a regulatory enzyme. Anaerobically and aerobically grown yeast contains 3-hydroxy-3-methylglutaryl-CoA reductase, which is located in the mitochondrial fraction of the cell. Anaerobically grown yeast has a low specific activity of 3-hydroxy-3-methylglutaryl-CoA reductase and a low sterol content. Aeration of this yeast in buffer, without growth, results in an increase in the specific activity of the enzyme, which is paralleled by an increase in the sterol content. This induction has an oscillatory profile with yeast grown anaerobically for 24 h and a linear pattern with cells grown anaerobically for 72 h. With the latter type of yeast, glucose is necessary for an induction, whereas with the other yeast an induction occurs with and without glucose. By an anaerobic incubation in buffer of the yeast grown anaerobically for 24 h, the oscillatory profile can be transformed into a linear one. The extent of induction of the reductase is strictly dependent on the concentration of glucose present. Sterols increase in whole cells, but they do not increase in the mitochondrial fraction. The induction of 3-hydroxy-3-methylglutaryl-CoA reductase is strongly inhibited by cycloheximide, but is not affected by chloramphenicol. The induction of the enzyme is closely connected with the glucose metabolism of the cell; fructose, mannose, and ethanol can also induce the reductase.


Mechanism of 2-deoxy-D-glucose inhibition of cell-wall polysaccharide and glycoprotein biosyntheses in Saccharomyces cerevisiae. The mechanism of inhibition by 2-deoxy-D-glucose of the synthesis of yeast wall polysaccharides and glycoproteins was investigated in Saccharomyces cerevisiae cells and protoplasts. The extent of the inhibition of mannan and glucan synthesis was found to be dependent on whether glucose or mannose was used as the carbon source in the medium. During growth on glucose, 2-deoxy-D-glucose inhibited more intensively mannan than glucan formation. Biosynthesis of wall glucan was strongly suppressed in mannose medium. Selective incorporation of 2-deoxy-D-glucose occurred into that polysaccharide, synthesis of which was more inhibited under given conditions. Suggestive evidence has been obtained that the decisive factor for the proportion of glucan and mannan in the walls is the direction of glucose 6-phosphate/mannose 6-phosphate interconversion dependent on the exogeneous hexose. No close correlation was found between the inhibition of mannan synthesis and the appearance of the mannan-protein enzymes invertase and acid phosphatase. Effect of 2-deoxy-D-glucose was therefore investigated on the parallel synthesis of protein, mannan and several extracellular and intracellular enzymes in protoplasts grown on glucose and mannose. The results obtained pointed out that the hindrance of the secretion of mannan-protein enzymes is of a complex nature and related more to the inhibition of synthesis of the protein moiety than to the inhibition of glycosylation. Synthesis of several enzymes was found to be a subject of a metabolic control by 2-deoxy-D-glucose or its metabolites.


Quantitative binding of antibiotics to ribosomes from a yeast mutant altered on the peptidyl-transferase center. Quantitative binding studies of [G-3H]anisomycin and [acetyl-14C]trichodermin to sensitive and resistant 80-S ribosomes from yeasts are described in this work. A single mutation, most probably affecting the ribosome peptidyl transferase centre, appears to have pleiotropic effects on the ribosome leading to resistance to trichodermin and anisomycin and to an increased sensitivity to sparsomycin. Resistance to trichodermin is due to a reduced affinity of ribosomes from the mutant for the antibiotic. Ribosomes from the sensitive strain (Y 1661 bind [acetyl-14C]trichodermin with a dissociation constant of 0.99 muM while those from the resistant one (TR1) bind [acetyl-14C]trichodermin with a dissociation constant of 15.4 muM. Similar results are obtained when the binding of [acetyl-14C]trichodermin to Y 166 and TR1 60-S subunits is studied. The mutant TR1 is also resistant to anisomycin. Although trichodermin and anisomycin bind to the ribosome at mutually exclusive sites, the higher affinity binding of [G-3H]anisomycin that is responsible for the inhibition of the peptidyl transferase center is practically identical for Y 166 and TR1 ribosomes. Therefore, the mutation in the ribosome leading to resistance to trichodermin and anisomycin decreases the affinity for trichodermin but not for anisomycin. Trichodermin, trichothecin and fusarenon X inhibit the binding of [G-3H]anisomycin to TR1 ribosomes to a lower extent than to Y 166 ribosomes, suggesting that the resistance of TR1 ribosomes to the effects of trichothecin and fusarenon X is caused by a decrease in the affinity of the ribosomes for these drugs, as was seen with trichodermin. On the other hand, verrucarin A inhibits [G-3H]anisomycin binding to Y 166 and TR1 ribosomes to a similar extent and therefore its affinity for the ribosome does not appear to be affected by the mutation leading to resistance. Trichothecin, trichodermin and fusarenon X appear to have a common binding site on the 60-S ribosomal subunits, which overlaps or is closely linked to the binding sites of anisomycin and verrucarin A.


Electrodialysis of lipopolysaccharides and their conversion to uniform salt forms. Ions of low molecular weight like metal cations and basic amines are present in lipopolysaccharides regardless of the isolation procedure employed. They are present in salt form with the acidic groups of the molecule and, partly, bound by chelation. Electrodialysis which removed a large proportion of these basic materials led to acidic lipopolysaccharides often with reduced solubility. Electrodialyzed lopopolysaccharides could be rendered soluble by neutralizing with alkali or with a basic amine. Depending on the base employed for neutralization preparations were obtained which showed in water distinct differences in solubility, viscosity and opalescence. These differences were related to differences in the sedimentation coefficients of the various salt forms. Neutralization with triethylamine led in all cases to highly soluble preparations with low sedimentation coefficients, while, on the other hand, neutralization with Mg(OH)2 led in most cases to insoluble preparations. The acidic lipopolysaccharides obtained by electrodialysis deteriorate on storing in a freeze-dried form. On heating in distilled water autohydrolysis occurs and free lipid A is liberated. The lipid A which is so far known as a water-insoluble material showed increased solubility when prepared from electrodialyzed lipopolysaccharides.


Regulation of protein secretion and metabolism in rat salivary glands. Effects of norepinephrine and carbachol on the glycogenolysis in submaxillary glands. Carbachol and norepinephrine induce glycogen breakdown in rat submaxillary glands incubated in vitro. These effects are suppressed by specific inhibitors of cholinergic receptors (atropine, a muscarinic blocker) and of adrenergic receptors (propranolol, a beta-blocker and phentolamine, an alpha-blocker). The beta-adrenergic effect seems to be mediated through the adenosine 3':5'-monophosphate system, whereas the alpha-adrenergic and cholinergic effects are dependent of Ca2+ influx into cell. In the two latter systems, it is suggested that a direct activation of phosphorylase b kinase by calcium takes place. These data clearly indicate that glycogenolysis in rat submaxillary glands in vitro can be independently affected by sympathetic and parasympathetic agents via specific receptors.


tRNA conformation and magnesium binding. A study of a yeast phenylalanine-specific tRNA by a fluorescent indicator and differential melting curves. The binding of Mg2+ to tRNAPhe (yeast) in three conformational states was studied at 10, 30, 45, and 70 degrees C by the fluorescence indicator 8-hydroxyquinoline 5-sulphonic acid in the presence of 0.032 M monovalent cations (Na+). At temperatures below those characteristic for early melting (completely folded tRNA) the Scatchard plots are biphasic. They were well fitted by two classes of noninteracting binding sites with stability constants independent of temperature (KA = 9X10(4), KB = 6X10(3) M-1). In partially unfolded tRNA the strong binding process is co-operative. A single class of weak sites was found in the statistically coiled conformation at 70 degrees C (KB = 3.3X103 M-1). The total number of binding sites is 23 +/- 5; differences for the folded and unfolded conformations are smaller than 1. The influence of Mg2+ on the stability of the conformational elements of tRNAPhe (yeast) and its CCA-half (i.e. nucleotides 38--76) was determined by differential ultraviolet absorbance and depolarisation melting curves using the fluorescence of the Y base. Tertiary structure corresponding to early melting is stabilized by strongly bound Mg2+, whereas all other melting transitions are only influenced by Mg2+ bound at weak sites. The stability constants of tertiary structure obtained from the melting experiments can quantitatively be described by assuming that 5 +/- 1 non-interacting strong sites as characterized by the fluorescence titrations are converted to weak sites upon unfolding of the tertiary structure. Co-operative interaction of Mg2+ with the 5 strong sites in the folded conformation of tRNA can be ruled out. Strong binding of Mg2+ to completely folded tRNA does not produce a conformational transition changing ultraviolet absorbance, circular dichroism and sedimentation coefficient.


Isolation and partial characterisation of the relaxation protein from nuclei of cultured mouse and human cells. A protein, called relaxation protein because of its ability to remove superhelical turns in closed-circular DNA, has been isolated and partially characterized from the nuclei of LA9 mouse and HeLa cells. The purification was facilitated by an assay method, with PM2 DNA, which used the fluorescence enhancement of the intercalating dye ethidium bromide upon binding to the closed-circular DNA. The amount of dye bound depends upon the degree of the superhelix density of the DNA. The relaxation products were analysed by the buoyant separation method in CsCl containing ethidium bromide and were shown to be completely relaxed. The purification resulted in a single band in a dodecylsulfate gel electrophoresis with an apparent molecular weight of 37000. The pH optimum is 7.0 and the optimal salt concentration is 0.2 M NaCl. The relaxation protein removes negative as well as positive supercoils, the latter generated by the interaction of ethidium bromide with closed-circular DNA. Relaxation of positive supercoils results, after removal of the dye, in the formation of molecules with superhelix densities exceeding that of native PM2 DNA (0.054). The highest negative superhelix density observed was -0.098 +/- 0.001. The corresponding positive superhelix density has been calculated to be + 0.023. A nicking--swivelling--closing mechanism is postulated, but nicked intermediates have so far not been demonstrated. The relaxation protein is not inhibited by known mammalian endonuclease I inhibitors, except for denatured DNA, and does not possess a conventional polynucleotide ligase activity. The relaxation activity was found to be predominantly in the nuclei, with only small amounts present in the cytoplasm and mitochondria. The biological function of transient swivels induced by the relaxation protein is not known. However, transient swivels are considered necessary or useful in the replication of closed-circular DNA or long linear DNA, respectively. Relaxation protein could replace the combined action of an endonuclease and a ligase ahead of the replication fork. Alternatively, transient swivels could be involved in the transcription process.


Equivalent and non-equivalent binding sites for tRNA on aminoacyl-tRNA synthetases. Complexes between tRNAPhe (yeast), tRNASer (yeast) and tRNATyr (Escherichia coli) and their cognate aminoacyl-tRNA synthetases have been studied by sedimentation velocity runs in an analytical ultracentrifuge. The amount of complex formation was determined by the absorption and the sedimentation coefficients of the fast-moving boundary in the presence of excess tRNA or excess synthetase respectively. The same method has been applied to unspecific combinations of tRNAs and synthetases. Inactive material of tRNA or synthetase does not influence the results. 1. Two moles of tRNAPhe can be bound to one mole of phenylalanyl-tRNA synthetase with a binding constant greater than 10(6) M-1. The binding constants for both tRNAs are very similar; the binding sites are independent of each other. Omission of Mg2+ does not prevent binding. 2. Two moles of tRNASer can be bound to one mole of Seryl-tRNA synthetase; the binding of the first and second tRNA is non-equivalent, K1 greater than 10(6) M-1, K2 is determined to be 1.3 X 10(5) M-1 at pH 7.2. Omission of Mg2+ prevents complex formation. 3. Tyrosyl-tRNA synthetase behaves very similarly to seryl-tRNA synthetase. The binding constant for the weakly bound tRNA is 2.3 X 10(5) M-1 at pH 7.2, and 2.5 X 10(6) M-1 at pH 6.0. No complexes are observed in the absence of Mg2+. 4. Unspecific binding was only obtained with phenylalanyl-tRNA synthetase. It binds tRNASer (yeast), tRNAAla (yeast) and tRNATyr (E. coli) with a binding constant about 100 times lower compared to its cognate tRNA. The binding data are discussed with respect to the tertiary structure of the tRNAs, the subunit structure of the synthetases and the possible physical basis for the non-equivalence of binding sites.


[Mechanism for the condensation reaction of fatty-acid biosynthesis (author's transl)]. The spontaneous hydrogen-deuterium exchange of the methylene group of malonyl-thioesters was investigated by nuclear-magnetic-resonance (NMR) spectroscopy using the model compound S-malonyl-N-acetylcysteamine. The half life of the methylene proteins is 12 to 16 min in 0.1 M K-phosphate buffer at pH 6.5 to 7.0 at 25 degrees C, the conditions of maximal activity of fatty acid synthetase from yeast. Proton catalysis was used for the quick preparation of deuterium- and tritium-labeled malonylthioesters. Compared with malonyl-CoA, dideutero-malonyl-CoA had no primary isotope effect on the reaction velocity of the yeast enzyme catalysed fatty acid synthesis, in which the rate limiting step is the condensation reaction. Although deuterium oxide had a solvent isotope effect, there was no difference in reaction velocities between malonyl CoA and dideuteromalonyl CoA in deuterium oxide. The condensation reaction was investiaged separately from the overall fatty acid synthesis using beta-ketoacyl-acyl-carrier-protein (ACP) synthetase (condensing enzyme) of Escherichia coli. The condensation reaction with deuteromalonyl-ACP had no kinetic isotope effect, in agreement with the observations on the overall reaction. However, in this case no solvent isotope effect was observed with 2H2O. When the condensation reaction was carried out in the presence of tritiated water, there was no incorporation of label into the reaction product acetoacetyl-thioester, excluding proton exchange with the solvent. The results exclude a mechanism for the condensation reaction involving a malonyl carbanion and its acylation as intermediates in the sense of an organic-chemical malonic ester synthesis, and they indicate that the condensation reaction follows a concerted mechanism: The formation of the new carbon-carbon bond is coupled with the cleavage of the carboxyl bond of the malonyl group.