Kinetics of pepsin-initiated coagulation of kappa-casein.

The kinetics of pepsin initiated coagulation of kappa-casein have been studied at pH 5.8. The primary and secondary phases of coagulation are shown to proceed simultaneously. The theory of enzymatically initiated clotting reactions proposed by Payens (Payens, T.A.J. (1976) Neth. Milk Dairy J. 30, 55--59) has been applied to this clotting system and has been used to obtain rate constants for the secondary phase of coagulation. As expected, clotting rate constants for kappa-casein increase with pepsin concentration. An activation energy of 30.6 kcal/mol has been obtained for the secondary phase of coagulation. Turbidity measurements are a convenient means for studying the secondary phase of coagulation but do not provide an unambiguous means for studying the primary phase of the reaction.


Effects of benzimidazole on the purine and pyrimidine metabolism of yeast.

Yeast cells inhibited by benzimidazole accumulate hypoxanthine with associated efflux of xanthine. Unlike control cells, inhibited cells contain no detectable free UMP and CMP. Benzimidazole decreases uptake of [8-14C]hypoxanthine into the intracellular pool of hypoxanthine and xanthine but causes radioactive xanthine to accumulate in the medium. In inhibited cultures there is a threefold increase in incorporation of [8-14C]hypoxanthine into the total (intracellular plus extracellular) xanthine. Uptake of [8-14C]hypoxanthine into free nucleotides and into bound adenine and guanine was inhibited by 70%. Uptake of [U-14C]glycine into IMP, AMP, GMP, DNA and RNA was also substantially decreased. Incorporation of [2-14C]uracil into the intracellular uracil pool was inhibited by 30% and into free uridine and cytidine by over 90%. Benzimidazole inhibited incorporation of [8-3H]IMP into AMP and GMP, and decreased substantially the activity of glutamine-amidophosphoribosyltransferase (EC 2.4.2.14). Yeast cultures were shown to N-ribotylate benzimidazole. Results are consistent with benzimidazole inhibiting yeast growth by competing for P-rib-PP and so depriving other ribotylation processes such as the 'salvage' pathways and de novo synthesis of purines and pyrimidines.


Stimulation of renin secretion from the intact kidney and from isolated glomeruli by the calcium ionophore A23187.

The ionophore A23187 evoked a dose-dependent release of renin from the isolated perfused cat kidney, which was inhibited by calcium deprivation and adrenergic blockade. The latter finding indicates that the effects of A23187 on the intact kidney are mediated mainly by catecholamine release from sympathetic nerve endings. Ionophore also elicited a concentration-dependent enhancement of renin secretion from a pure preparation of glomeruli isolated from cat kidney; this stimulation was still manifest when the glomeruli were superfused with a calcium-free solution. These findings indicate that A23187 evokes renin secretion from juxtaglomerular cells by mobilizing cellular calcium and support the view that an increase in intracellular calcium is intimately involved in the mechanism of renin secretion.


Regulation of glucosamine-6-phosphate deaminase synthesis in yeast.

A basal level of glucosamine-6-phosphate deaminase is detected in yeast cells grown on glucose. However, a burst of enzyme production occurs in the presence of N-acetylglucosamine in pathogenic Candida albicans and non-pathogenic Saccharomyces cervisiae. The enzyme synthesis stops and its concentration in the cells declines rapidly as soon as N-acetylglucosamine is removed from the medium. Experiments with RNA- and protein-synthesis inhibitors indicate that the appearance of new enzyme activity is dependent on concomitant new protein synthesis and the inducer operates at a transcriptional level. However, inhibition of DNA synthesis either by hydroxyurea or by mitomycin-C does not impair the synthesis of glucosamine-6-phosphate deaminase.


4-Hydroxybenzyl alcohol. A metabolite produced during the biosynthesis of thiamine in Escherichia coli.

4-Hydroxybenzyl alcohol was identified by gas chromatography-mass spectrometry as a metabolite of Escherichia coli when it is grown on a medium containing no thiamine or 4-methyl-5-beta-hydroxyethyl thiazole. 4-Hydroxybenzyl alcohol was found to be derived from L-tyrosine and the amount produced was found to be inhibited by the addition of thiamine to the growth medium. The amount of 4-hydroxybenzyl alcohol produced, as measured by isotopic dilution, was shown to be equivalent to the amount of thiamine formed. Based on these observations, it was concluded that 4-hydroxybenzyl alcohol is the cleavage product produced during the biosynthesis of the thiazole moiety of thiamine from tyrosine.


[The effect of guanosinetetraphosphate on rRNA synthesis in E. coli extracts].

The synthesis of rRNA in the ribosome-free extracts S100 of E. coli cells was about 30 and 60% of total transcript when E. coli DNA and DNA of lambda rifd 18 phage were used respectively. The synthesis of rRNA with both types of DNA was inhibited in 5--6 times by 0.8 mM ppGpp, while the synthesis of total RNA decreased only two-fold. Selective action of ppGpp on rRNA synthesis is due to the intensive inhibition of the initiation of transcription of the appropriate genes. The rRNA synthesis and the inhibitory capacity of ppGpp was shown to dependend on the KCl concentration in S 100 extracts. These results indicate that ppGpp is the main factor controlling rRNA synthesis both in isolated RNA polymerase system and in cell-free extracts.


[Comparative study of glycosidase from cattle liver and exoglycanase from Aspergillus awamori].

Anomerities of products were estimated for glucosidases from cattle liver and Aspergillus awamori. It was demonstrated that the enzyme from cattle liver is alpha-glucosidase and that from Asp. awamori is exogluconase. It was demonstrated that alpha-glucosidase hydrolyzes the C1--O bond in the course of reaction. delta-Lactone of gluconic acid is a competitive inhibitor for both enzymes. The secondary kinetic isotope effects for both enzymes were measured. The isotope effect for alpha-glucosidase is equal to 1, for exogluconase 1,1 for glycogen and 1,18 for maltose. Some aspects of mechanisms of both enzymes are discussed in terms of the data obtained.


[Isolation and properties of DNA-cytosine-methylase I from Escherichia coli MRE 600].

DNA-cytosine-methylase I was isolated and purified to homogeneity. The yield made up to about 30% of total activity. The enzyme molecular weight as determined by centrifugation in a sucrose gradient, by gel filtration and by electrophoresis in polyacrylamide gel in the presence of sodium dodecyl sulfate was found to be 45,000. The Michaelis constant was 1,8 . 10(-6) M for SAM and 2 . 10(-4) M for DNA. DNA-cytosine-methylase I modifies phage lambda DNA in 60 sites. This modification does not protect DNA from the effects of restriction endonucleases HpaII and BsuRI. The enzyme methylates DNA in the nucleotide sequence: 5'...Pur-MC-C-G-G-Pyr...3'.


[Nature of the intermediate compound formed during catalysis by pepsin].

The applicability of the free energies linearity principle to catalysis by pepsin may indicate that the mechanism of formation of a covalent pepsin intermediate with the second (amine or alcohol) part of the hydrolyzed substrate is a true one. The choice has been made from consideration of three possible types of mechanisms covalent binding, complex with a nonionized NH2-group and the absence of an activated intermediate.


[Substrate specificity of peptidases catalyzing LH-RH degradation in hypothalamus, liver and heart of rat].

Degradation of [125I]-LH-RH by peptidases of hypothalamus, liver and heart of the rat and the effects of LH-RH, LH-RH antagonist D-Phe2-Phe3-D-Phe6-LH-RH, LH-RH5-10, oxytocin, bradikinin, thyrotrophin-releasing hormone, melanocyte-inhibiting factor, luteinizing, follicle-stimulating, lactogenic and growth hormones were studied. It was shown that the degradation was inhibited with maximal efficiency by non-labelled LH-RH (Ki = 1,7--2,0 . 10(-6) M). This observation is indicative of peptidase specificity for LH-RH. It is assumed that specific peptidases of liver and heart are involved in the reglation of LH-RH concentration in these organs.


Interpretation of the results of investigating molecular fossils.

The difficulties and possible errors in interpreting the results of investigating molecular fossils within the scope of the problem of chemical evolution and origin of life on the earth are examined. These difficulties can be largely overcome on the basis of modeling processes of the transformation of organic matter under different geological conditions.


Clinical effects of L-5-hydroxytryptophan administration in chronic schizophrenic patients.

L-5-Hydroxytryptophan (L-5HTP) and the peripheral decarboxylase inhibitor carbidopa were administered to chronic schizophrenic patients in three separate experiments using a double-blind placebo-controlled crossover design. The three experiments were: (i) L-5HTP administration to 15 patients who had been withdrawn from all neuroleptic medication; (ii) L-5HTP administration to seven patients maintained on haloperidol; (iii) L-5HTP administration to nine patients maintained on chlorpromazine. Although the groups were diagnostically homogeneous, individual responses were highly variable. Considering each group as a whole, the only significant changes in rated psychosis consisted of an increase in the first group consequent to coming off neuroleptic medication and an increase in psychosis scores associated with adding L-5HTP to chlorpromazine. Neuroleptics apparently sensitize the central nervous system to the effects of L-5HTP loading. Acute exacerbations of psychosis induced by L-5HTP can be reversed by neuroleptics. Our experience does not give encouragement to the hypothesis that schizophrenic illnesses arise consequent to a deficit of serotonergic function that can be treated by giving a serotonin precursor in pharmacological quantities.


Selective attention, cortical evoked responses, and brain function in human subjects: a critical review and theory.

A theoretical framework is proposed to account for the facts of selective attention in terms of cortical redundancy and cortical-subcortical interactions as measured by the Average Evoked Response and the background EEG. The recent research concerning AER correlations of selective attention is reviewed and found to be lacking in methodological coherence. This lack is found to contaminate existing theory regarding selective attention and brain function. An alternative approach is explored and its findings are found to yield the present theory.


Mechanisms of erythrocyte sedimentation.

Concomitant mechanisms of red-cell sedimentation are discussed: 1. physical 2. biological (the effects of plasma proteins, viscosity, and the number and size of erythrocytes on the rate of sedimentation). 3. an up-to-date review of the principal methods and systems used to measure the sedimentation rate--Automation of the Westergren initial methodology.


Drug latentiation in cancer chemotherapy.

Latent antitumour agents require spontaneous or enzyme-catalysed activation to cytotoxic species in vivo. Activation may occur principally in normal tissues or in the target tumour. Agents of this type are discussed and mechanisms of drug action and selectivity are described, with reference to appropriate examples. The comparatively poor therapeutic activity of many agents designed for selective activation in tumours is attributed to the often unfavourable distribution of activating enzymes between normal and neoplastic tissues. Factors to be considered in the design of new enzyme-activated agents are discussed and possible artefacts involved in the assay of tumour enzymes are described. Some novel approaches to the design of latent antitumour agents are also discussed.


Ultrastructural study of normal and leukaemic leucocyte processes.

Cellular processes of leucocytes from both normal and leukaemic subjects were studied at the ultrastructural level. By high voltage transmission electron microscopy without a metal coating, more surface features could be seen in the cells than were observed by either scanning electron microscopy or conventional transmission electron microscopy. The technique was shown to be especially useful as it allows direct visualisation of the cell surface structure at high resolution without artefact-inducing preparative processes. Demonstrating receptor sites with this technique opens up the possibility of studying lymphocyte microvilli in greater detail.


Effects of chronic alcoholism on the pituitary-gonadal function of women during menopausal transition and in the post menopausal period.

The hypothalamo-pituitary gonadal function was evaluated in eleven chronically alcoholic menopausal women by measurement of basal serum oestradiol, FSH, LH and prolactin, followed by LHRH-TRH test and administration of clomiphene citrate. All patients had hepatic damage, fibrosteatosis or cirrhosis. Two subgroups have been isolated according to urinary and serum estrogen levels: seven patients with urinary estrogen output less than 14 microgram per 24 h and plasma oestradiol less than 40 pg per ml were considered as post menopausal women: basal values of FSH and LH and their response to LHRH did not differ from that observed in normal menopausal women; clomiphene citrate induced a significant suppression of FSH and LH blood levels. Four women with urinary estrogen output greater than 14 microgram per 24 h and plasma oestradiol greater than 40 pg per ml were considered in menopausal transition. Their basal and post LHRH-FSH blood levels were lower than in the control group. These results suggest a normal hypothalamo-pituitary-gonadal axis at least in the post menopausal alcoholic women.


Analysis of the venom of the Sydney funnel-web spider, Atrax robustus using gas chromatography mass spectrometry.

Thirteen compounds have been identified using gas chromatography mass spectrometry in the venom of the Sydney funnel-web spider, Atrax robustus. The compounds were identified as their trimethylsilyl or pentafluoropropionate derivatives and were citric acid, lactic acid, phosphoric acid, glycerol, urea, glucose, gamma-aminobutyric acid, glycine, spermidine, spermine, tyramine and octopamine. Female venom contained trace quantities of 5-methyoxytryptamine which was not detected in male venom. Quantitative determination of tyramine and octopamine was achieved using chemical ionization (CH4) gas chromatography mass spectrometry and deuterated internal standards.


Real-time analysis of breath using an atmospheric pressure ionization mass spectrometer.

A new technique is reported resulting in the direct, instantaneous analyses of trace compounds in breath. The analyses were performed using a commercial atmospheric pressure chemical ionization mass spectrometer (TAGA TM2000 APCI mass spectrometer). A known flow of breath sample is introduced into the ionization region of the mass spectrometer. The study includes the measurement and monitoring in real-time, of breath ammonia during a 24 hour and a 48 hour period. The ammonia profiles indicate a personalized daily pattern associated with each subject. This method appears to be of potential value in routine detection and treatment of hyperammonemia patients. Results also show that it is possible to obtain instantaneous analyses of several naturally occurring metabolites and other substances on breath in the ppm to ppt range, suggesting a number of diagnostic research applications.


Process characteristics of cell lysis mutants of Saccharomyces cerevisiae.

Several temperature-sensitive lysis mutants of Saccharomyces cerevisiae were selected according to their ability to release alkaline phosphatase when incubated at a nonpermissive temperature. For two mutants, cell lysis and release of alkaline phosphatase reached a maximum when cells in the logarithmic growth phase were shifted to the nonpermissive temperature. Morphological changes, as well as changes in macromolecular composition of the cells, were observed. Growth is necessary and oxygen is important for the expression of cell lysis at the nonpermissive temperature.


[Changes in pressor and depressor reactions following partial pancreatectomy].

Experiments were conducted on 39 mongrel pubertal dogs. The course of pressor and depressor reactions under conditions of normal vital activity and after partial corporocaudal resection of the pancreas was studied. The principal indices characterizing the changes of pressor reaction to noradrenaline, and of the depressor one -- to bradykinin and kallikrein before and 10 to 12 days after the corporocaudal resection of the pancreas were determined. Resection of the corporo-caudal part of the pancreas intensified the pressor reactions to noradrenaline, and depressor ones to bradykinin and kallikrein; it increased the initial negative chronotropic effect of catecholamines on the heart, and also enhanced the positive chronotropic effect of noradrenaline, kallikrein and bradykinin on the heart.


[T- and B-lymphocytes in patients with chronic renal failure and in recipients of cadaveric allokidneys during the immediate posttransplant period].

Investigations of the thymus-dependent and thymus-independent lymphocytes populations of patients with chronic renal failure showed the activity of the T-lymphocytes system to be depressed in these cases. Both the lymphocyte populations took part in the rejection, but the degree of their participation differed. There was a low activation of T-lymphocytes and a high activation of B-lymphocytes in case of inflammatory processes, abscess, frunculosis, hematoma, etc., when stable doses of immunodepressants were used. The evidence of participation of T- and B-lymphocytes in the rejection opens new approaches to the diagnosis of different pathological conditions in the recipient's organism.


The medical management of renal artery stenosis in transplant recipients.

The investigation, management and clinical course of 12 patients developing stenosis of the renal artery following transplantation are described. The possible aetiology of the three arteriographic patterns of stenosis is discussed. Surgical correction of graft arterial stenosis is difficult and may lead to graft loss, whereas the outcome with antihypertensive drug treatment with or without anticoagulants is good. Surgery should only be contemplated if medical treatment is failing or if renal function is deteriorating.


Highly selective vagotomy with excision of the ulcer compared with gastrectomy for gastric ulcer in a randomized trial.

Fifty-six patients with benign gastric ulcer of the body of the stomach have been entered into a randomized trial of highly selective vagotomy with excision of the ulcer (HSVE) (26 cases) against standard Billroth I partial gastrectomy (BI) (30 cases). The operations were carried out by all grades of surgical staff. No patient died within 1 month of operation. Postoperative morbidity was greater after gastrectomy than after HSVE. At an average follow-up of about 4 years, functional results according to a modified Visick classification were similar in both groups, with about 75 per cent good results. Two recurrent ulcers occurred after gastrectomy (7 per cent) and 4 after HSVE (15 per cent). Neither operation has a distinct advantage at this stage.


The stripping of varicose veins: a clinical trial of intermittent compression dressings.

This study compares a standard method of care for patients following excision and ligation of varicose veins with a new regimen which involves intermittent compression dressings. In a fully randomized between-patient prospective trial it has been found that the use of such dressings results in a significant reduction in postoperative pain and in the length of hospitalization and indicates that such dressings may improve the healing of surgical wounds.


Internal fixation versus primary prosthetic replacement in acute femoral neck fractures: a prospective, randomized clinical study.

A prospective, randomized clinical study has been performed on 104 patients with an acute femoral neck fracture, comparing internal fixation (von Bahr screws) with primary prosthetic replacement (Christiansen endoprosthesis). Immediate weight bearing was allowed in both groups. The postoperative mortality rate was similar in the two groups. Internal fixation proved to be a less time-consuming operation, gave a shorter hospitalization time and was associated with a significantly reduced morbidity rate compared with prosthetic replacement. No blood transfusion was needed in the internal fixation group. Primary prosthetic replacement was associated with earlier postoperative mobilization, probably gave a more definitive treatment with fewer reoperations, and showed better results at 1-year follow-up.


A clinical trial of endolymphatic therapy in malignant melanoma: interim report of the progress of the Medical Research Council trial.

This report presents the interim results of the MRC trial on the treatment of Stage I melanoma of the lower limb by endolymphatic therapy. Over a 10-year period a group of 146 patients has been entered into the trial. Although total recurrence rates were not significantly affected by endolymphatic therapy, recurrence in the lymph nodes was largely prevented. More patients in the standard treatment group needed the more major procedure of block dissection. The survival rates for the endolymphatic and standard treatment groups did not differ significantly.


Beta-adrenoceptor-blocking drugs and blood sugar control in diabetes mellitus.

The effects on diabetic control of the relative cardioselective beta-blocker metoprolol and the non-selective drug propranolol were compared in 20 hypertensive diabetic patients receiving diet alone or diet and oral hypoglycaemic agents. Each drug was given for one month in a double-blind, cross-over study. Fasting, noon, and mid-afternoon blood sugar concentrations rose by 1.0-1.5 mmol/l (18-27 mg/100 ml). The rise with propranolol was not significantly greater than with metoprolol. In a few patients the rise was clinically important. The small overall change observed in diabetic control should not deter the use of beta-blockers in non-insulin-dependent diabetics, provided control is carefully monitored at the onset of treatment.


Improved metabolic profiles in insulin-treated diabetic patients given an alpha-glucosidehydrolase inhibitor.

An alpha-glucosidehydrolase inhibitor (acarbose; BAY g 5421) taken with food was compared with dummy tablets in seven insulin-treated diabetic patients over eight-hour periods that included breakfast, lunch, and two snacks. Acarbose diminished the postprandial increases in blood glucose, lactate, and pyruvate concentrations and may therefore be of value in the management of insulin-dependent diabetes.


Comparison of natriuretic, uricosuric, and antihypertensive properties of tienilic acid, bendrofluazide, and spironolactone.

The antihypertensive properties of the new diuretic tienilic acid were investigated. Thirteen previously untreated hypertensive patients took part in a double-blind crossover study in which 30 days' treatment with tienilic acid 250 mg, bendrofluazide 5 mg, and spironolactone 100 mg were compared. Bendrofluazide caused the greatest natriuresis on the first treatment day and the most rapid fall in blood pressure. The ultimate antihypertensive effect of all three drugs was similar. Tienilic acid caused a noticeable reduction in serum urate concentrations and a rise in urate clearance, in contrast to the other two agents, which caused slight urate retention. Tienilic acid and bendrofluazide caused falls and spironolactone a rise in plasma potassium concentrations. No untoward effects were seen from any of the drugs. It is concluded that tienilic acid is a moderately potent diuretic that lowers plasma urate concentrations. It may be the drug of first choice for hypertensive patients who already have gout or are likely to develop it when taking thiazide diuretics.


Cadaver nephrectomy: an operation on the donor's family.

Thirty-two relatives of cadaver kidney donors were interviewed six months or longer after the donor's death. Most had  positive attitudes to kidney transplantation that had been strengthened by experience, especially when they knew that they were fulfilling the donor's wishes. Twenty-three of the relatives had gained some solace from knowing that others might benefit from their misfortune, but three claimed adverse effects. In identifying the factors that influenced them to grant permission or hesitate, relatives revealed defects in the way their permission had been sought. Twelve did not clearly understand the donor's hopeless prognosis until then, and seven reacted adversely to the interviewers, finding them blunt and callous. Nevertheless, most were pleased that they had been asked. Doctors who care for unconscious, dying patients should try to give relatives explicit information on the patient's condition, whether or not the patient is a potential kidney donor, and permission for organ recovery should not be sought until they understand that death is inevitable.


Urinary excretion of factor VIII after renal transplantation.

The urinary excretion of factor-VIII-related antigen (VIIIRAg) was measured in 72 patients with kidney transplants and compared with that of two end-products of fibrin-fibrinogen lysis (fragments D and E) to assess their usefulness in monitoring the onset of rejection episodes. Specific and sensitive radioimmunoassays were used to measure the three proteins. Unconcentrated urine samples of 24-hour collections were obtained from 20 healthy subjects, 48 patients with stable transplants, and 24 patients with recent transplants serially followed up from the day of transplantation. Factor VIIIRAg and fragments E and D were not detectable in the urine from healthy subjects but were present in 39%, 60%, and 100% respectively of samples from patients with stable transplants. During 33 acute rejection episodes in 19 patients with recent transplants factor VIIIRAg and fragments E and D were significantly increased above the values observed in patients with stable transplants in 82%, 73%, and 64% of samples respectively; in patients with recent transplants showing no clinical sign of rejection increased excretion of these proteins was observed in 11%, 26%, and 22% of samples respectively. The presence of factor VIIIRAg in urine from patients with kidney allografts suggests that endothelial cell-factor VIII-platelet interactions might pay a key part in the pathogenesis of acute rejection. The results suggest that the assay of factor VIIIRAg in urine is more useful than assays of fragments D and E as a corroborative index of transplant rejection.


Localization and molecular heterogeneity of cholecystokinin in the central and peripheral nervous system.

Immunocytochemistry and radioimmunochemistry demonstrate the occurrence of the gastrointestinal hormone cholecystokinin (CCK) in both the central and peripheral nervous system of the guinea pig. CCK nerves are particularly numerous in the neocortex, the hippocampus, the amygdaloid nuclei, the hypothalamus, the spinal cord and in the colon. The nerves contain 5 molecular components of CCK, with gel chromatographical elution constants (Kav) of 0.05, 0.50, 0.90, 1.10 and 1.30, respectively. The four latter correspond to triacontatriapeptide CCK and its COOH-terminal dodeca-, octa- and tetrapeptide portions, respectively. Cholecystokinins are hence widely distributed in the nervous system and occur in the substantial quantities (greater than or equal to 0.2 nmol CCK-8-equiv./g) in several distinct regions.


Salmonella investigation in an Ontario feed mill.

The frequency of Salmonella contamination of feedstuffs and finished broiler chicken feeds at an Ontario feed mill were investigated over a four-month period. Samples of feed ingredients and finished pelleted feeds were collected at various points during manufacture and cultured in trypticase soy broth prior to selective enrichment for isolation of Salmonella. Salmonella contamination was found in 4.3% of 93 finished pelleted broiler feeds examined. The contamination appeared to result primarily from the incorporation of contaminated animal protein ingredients into the feed. Meatmeal and the broiler, premix, which contained meatmeal as a filler, were most frequently contaminated followed by feather meal. Pelleting failed to eliminate the Salmonellae from the feeds. The methods used failed to detect Salmonella in the environment of the feed mill or its delivery trucks. Recommendations for control are made.


An indirect fluorescent antibody test for the detection of Cytauxzoon-like organisms in experimentally infected cats.

Antiserum to feline Cytauxzoon-like parasites was used in conjunction with labeled rabbit antisera to feline globulins to detect the presence of Cytauxzoon-like parasites in spleens of experimentally infected cats. Frozen spleen sections from 21 infected cats showed positively fluorescing masses within splenic veins and a diffuse scattering of discretely fluorescing cells in the red and white pulp. The distribution of fluorescence corresponded with the appearance of parasitized reticuloendothelial cells in histological preparations of spleen tissue. This indirect fluorescent antibody test consistently detected the presence of Cytauxzoon-like parasites in frozen spleen sections from experimentally infected cats.


An indirect fluorescent antibody test for antibodies to transmissible gastroenteritis of swine.

The indirect fluorescent antibody test was modified to provide a rapid technique for the detection, screening and titration of antibodies to transmissible gastroenteritis of pigs. Large numbers of slides containing transmissible gastroenteritis antigen were prepared by planting mixtures of infected and uninfected swine testicular cells onto multiwelled teflon-coated slides. After overnight incubation, about one-half of the cells in each well were infected which provided contrast to aid in detecting specific fluorescence in the presence of varying degrees of background staining. Following fixation, antigen slides were stored at -20 degrees C until used. The indirect fluorescent antibody test was compared to the virus neutralization test in both the screening and titration of swine sera containing transmissible gastroenteritis antibodies. The test was found to be sensitive and reliable and to offer certain advantages over the virus neutralization test.


A corneal model for studying the interaction between the endothelium and sensitized lymphocytes.

We wished to develop a simple model for morphological studies on the interaction between the corneal endothelium and specifically sensitized lymphocytes. Rabbits were transplanted with orthotopic allogeneic skin or corneal grafts. After the onset of the transplantation reaction, lymphoid cells from the recipient's spleen or preauricular lymph nodes were harvested and placed on the endothelial surfaces of the donor and recipient corneas which were incubated in tissue culture medium at 37 degree C for 4 hours before being examined by vital staining or scanning electron microscopy. Compared to the recipient, the donor endothelium contained more lymphoid cell aggregates and more corneal cells were damaged. The in vitro model seemed suitable for studying the cytotoxic behaviour of sensitized lymphocytes confronting the corneal endothelium.


Further taxonomic characterization of the genus Bdellovibrio.

Cultures of Bdellovibrio isolated from different geographic locations have been studied in terms of deoxyribonucleic acid analysis (% G + C, genome size, and DNA hybridization), cytochrome spectrum, and host range. Isolates of the genus exhibit a broad range of % G + C ranging from 37 to 51% and the genome sizes extend from 1300 x 10(6) to 1700 x 10(6) daltons. DNA hybridization continues to reveal a high level of genetic heterogeneity. Bdellovibrio 3294 exhibits 32% relative reassociation to Bdellovibrio W, 37% to Bdellovibrio stolpii Uki2, and an undetectible level to Bdellovibrio starrii A3.12 Bdellovibrio W is 23% related to B. starri A3.12 and 28.5% to B. stolpii Uki2. For the first time differential absorption techniques have revealed peaks of cytochrome b. The analysis of the cytochrome spectrum seems to be limited as a taxonomic tool since most of the recent isolates studied share a common cytochrome spectrum. Host-range studies have been found to be dependent on the experimental conditions, and with the exception of one isolate (B. starrii A3.12) the taxonomic significance of such techniques must be taken with caution.


Pseudotumor cerebri.

Pseudotumor cerebri is a clinical syndrome in which signs and, sometimes, symptoms of raised intracranial pressure are present but in which mental and neurological function are unaffected. Therefore, the diagnosis is reached after mass and other structural causes of raised pressure have been excluded. Many causes of pseudotumor have been suggested, not all of them well documented. Pathogenesis, however, includes cerebral edema, increased cerebral blood volume, and decreased cerebro spinal fluid (CSF) absorption. Except for the risk of vision in a minority of cases, the prognosis is excellent.


Fibrosing alveolitis.

Fibrosing alveolitis is a disease of unknown cause mainly involving the gas-exchanging portions of the lungs. It may occur in isolation and be called cryptogenic or idiopathic, in which case the clinical manifestations are mainly respiratory, or it may be associated with other disorders, such as rheumatoid arthritis. The histopathologic abnormalities of the pulmonary tissue are identical in either instance. Other names used for the disease have included usual interstitial pneumonia, desquamative interstitial pneumonia and the Hamman-Rich syndrome; these terms may describe different stages of the same pathologic process. Many authors in North America and those in the United Kingdom favour the term fibrosing alveolitis when describing chronic interstitial pneumonias. There may be accompanying nonspecific Immunologic abnormalities, which may denote that fibrosing alveolitis is part of the wide spectrum of diseases known as connective tissue disorders. Recently immune complexes have been found in the lung parenchyma; they probably result in the granulocyte destruction and reticuloendothelial proliferation seen in the acute phase of the disease.There are no specific diagnostic tests for the disease apart from lung biopsy, which can be performed at the time of thoracotomy or transbronchially, with the use of a flexible fibreoptic bronchoscope. Lavaged cells from the alveoli have also been obtained via the bronchoscope; in persons with fibrosing alveolitis a high proportion of these cells are neutrophils, and after corticosteroid treatment the proportion decreases. The progress of the disease can be followed by examination of these washings as well as by lung scanning with gallium-67 citrate. Newer methods of treatment using combinations of corticosteroids and immunosuppressant drugs are being evaluated and are initially proving to be successful.


Self-recording of blood pressure in the management of hypertension.

The efficacy of self-recording of blood pressure in the management of hypertension was assessed in a randomized clinical trial involving 140 persons who had been receiving antihypertensive therapy for a year or more, but whose diastolic blood pressure had remained at 95 mm Hg or higher. To control for the increased attention implicit in self-recording, which might affect blood pressure, the patients were assigned at random to one of the four groups: self-recording and monthly home visits, self-recording only, monthly home visits only, and neither self-recording nor monthly home visits. This design also permitted assessment of the effect of home visits. During the 6-month experiment no significant differences were apparent between the groups in either compliance or diastolic blood pressure. However, both self-recording and monthly home visits produced a reduction in blood pressure among patients who admitted to difficulty remembering to take their pills; a reduction was not seen among patients who said they had no such difficulty. This confirmed an earlier observation suggesting that this easily identified group of patients may be the most responsive to intervention programs.


Histiocytic lymphoma of the ileocecal region after chemotherapy for multiple myeloma.

Histiocytic lymphoma of the ileocecal region developed in a patient with multiple myeloma following successful long-term alkylating agent therapy. Five and one-half years after the diagnosis of myeloma, while in remission on cyclophosphamide therapy, the patient experienced severe abdominal right lower quadrant pain due to a large cecal lymphoma. A right hemicolectomy was performed with relief of symptoms. However, 9 months later, while still asymptomatic, routine physical examination revealed a recurrent right lower quadrant tumor. Radiation therapy decreased the size of the mass, but five months later partial small bowel obstruction occurred because of recurrent lymphomatous infiltration. The patient died 7 years after the diagnosis of myeloma with extensive abdominal lymphoma. There was no evidence of recurrent myeloma after the initial remission on cyclophosphamide therapy. This patient adds to the growing literature of a second malignancy occurring after prolonged successful chemotherapy of a primary neoplasm.


Eastern Cooperative Oncology Group experience with the rappaport classification of non-Hodgkin's lymphomas.

Eastern Cooperative Oncology Group experience in the clinical application of the Rappaport Classification on Non-Hodgkin's lymphomas (NHL) is reviewed in 670 cases studied since 1972. The diagnoses of institutional pathologists were reviewed by the Pathology Panel and Repository Center for Lymphoma Clinical Studies. Diagnostic agreement in regard to histologic pattern (nodular versus diffuse) was excellent (90%) but was less favorable when concurrence as to both pattern and cell type was assessed (82% in NLDP and 60% or less in other subtypes). Disagreement in regard to NHL diagnosis is related to the complexity of present nomenclature and to the lack of support of pathology activities within cooperative groups. It is suggested that patients entered into group NHL studies be randomized into favorable and unfavorable groups, primarily on the basis of histological pattern.


Nonepithelial tumors of the nasal cavity, paranasal sinuses and nasopharynx: a clinicopathologic study. X. Malignant lymphomas.

In our series of 256 nonepithelial tumors involving the nasal cavity, paranasal sinuses and nasopharynx, 21 were apparently primary malignant lymphomas, including 17 ordinary lymphomas and 4 cases of "midline malignant reticulosis." Of the 15 patients who had ordinary lymphomas and had adequate follow-up, 8 died of lymphoma, 4 were living with disseminated disease, 1 died of other causes with persistent lymphoma and only 2 (13%) had no evidence of recurrence at 8 and 9 years after diagnosis. The tumor was controlled in its primary site by radiotherapy in 13 of 14 patients; however, all but 2 of these patients eventually developed disseminated disease. Of the 3 patients who had midline malignant reticulosis (MMR) and had adequate follow-up, all died of disease. MMR represents an unusual variant of malignant lymphoma and often produces the clinical picture of lethal midline granuloma.


Phase I study of thymidine plus 5-fluorouracil infusions in advanced colorectal carcinoma.

In order to determine the minimal toxic dose of a 5-day infusion of 5-fluorouracil (5--FU) in combination with an infusion of thymidine (TdR), 12 patients, received TdR at a dose of 8 g/m2/day for 5 1/2 days, beginning at the same time as a 5-day infusion of 5-FU at doses of 5--20 mg/kg/day. Myelosuppression was the dose-limiting toxicity, and the minimal toxic dose of 5--FU was found to be 7.5 mg/kg/day. Gastrointestinal toxicity was minimal to absent. In eight patients with carcinoma of the colon who had received no prior chemotherapy, there were two patients with partial responses (at doses of 5.0 and 7.5 mg/kg/day of 5--FU), two patients with stable disease, one patient with progressive disease, and three patients with early death (two drug-related deaths and one disease-related death). In four patients who had received prior 5--FU, one had stable disease, one had progressive disease, and two had early death (one drug-related death). We conclude that the addition of TdR to 5--FU infusions changes the dose-limiting toxicity from gastrointestinal toxicity to myelosuppression. The minimal toxic dose is decreased to approximately one third of that when 5--FU is administered alone.


Phase II study of ICRF-159 in refractory metastatic breast cancer.

ICRF-159, at a dose of 300 mg/m2, was given orally every 8 hours for nine doses every 21 days to 40 patients with metastatic breast cancer refractory to hormonal therapy and cyclophosphamide, methotrexate, 5-fluorouracil, and adriamycin chemotherapy. Two patients with soft tissue disease had short-lived partial responses. The hematologic toxicity was severe. Three patients required rbc transfusions. Four patients became septic at the nadir of leukopenia; two of these patients died while leukopenic. Two patients had platelet counts less than 25,000/mm3. All patients who were nonevaluable or who had life-threatening or lethal toxicity were nonambulatory. Since the 19 nonambulatory patients had a median survival of only 1.25 months as compared to 7 months in ambulatory patients, it is recommended that future phase II trials in chemotherapy-refractory breast cancer be limited to ambulatory patients. Although ICRF-159 has minimal antineoplastic effects, it is not recommended for further investigations in metastatic breast cancer, even at more hematologically tolerable doses of 250 mg/m2 every 8 hours for nine doses.


Ifosfamide versus cyclophosphamide in combination drug therapy for metastatic breast cancer.

A combination of 5-fluorouracil (5-FU), adriamycin, and cyclophosphamide (FAC) was compared to a combination of 5-FU, adriamycin, and ifosfamide (FAI) in the treatment of metastatic breast cancer. All patients in the FAC and FAI groups also received nonspecific immunotherapy with bacillus Calmette-Guérin (BCG) and levamisole. Of 117 evaluable FAC patients, 19 (16%) achieved complete remission and 66 (56%) achieved partial remission. In the FAI group, eight of 49 (16%) evaluable patients achieved complete remission and 24 (50%) achieved partial remission. The response rates, durations of remission, and survival were similar in both groups. The combination of two immunotherapeutic agents (BCG and levamisole) did not have an additive effect since their results were similar to our previous experience with FAC-BCG and FAC-levamisole. In the FAI group, 25% of the patients had hematuria, while none of the patients in the FAC group had urinary complications. Nausea and vomiting were more severe in FAI-treated patients and some patients required iv fluids to correct dehydration. Ifosfamide in combination with 5-FU and adriamycin was more toxic than and not superior to cyclophosphamide.


Limited activity of ICRF-159 in advanced acute leukemia.

Twenty-eight patients with advanced acute nonlymphocytic leukemia, 16 with acute lymphoblastic leukemia, and two with acute undifferentiated leukemia were treated with ICRF-159. No patient achieved a complete remission and only three patients (6%) achieved a partial bone marrow remission. The only significant toxic effect was myelosuppression which probably contributed to the death of six patients. Five patients with acute nonlymphocytic leukemia and one with acute lymphoblastic leukemia received a combination of ICRF-159 and low-dose cytosine arabinoside. There were no remissions in this group and the toxic effects were more marked than with ICRF-159 alone. This study confirms the limited activity of ICRF-159 as a single agent in acute leukemia demonstrated in smaller series, and shows that, when used in combination with low-dose cytosine arabinoside, it was ineffective and resulted in increased toxicity. ICRF-159 alone or in combination with cytosine arabinoside has very limited activity in advanced adult acute leukemia.


Phase II trial of adriamycin in the treatment of advanced or recurrent endometrial carcinoma: a Gynecologic Oncology Group study.

Forty-three patients with advanced or recurrent endometrial carcinoma no longer amenable to management with surgery or radiotherapy were treated with adriamycin. Sixteen of the 43 patients demonstrated objective response to drug therapy with a greater than or equal to 50% reduction in the size of measurable disease. There were 11 complete responses among these 16 responders. Responders had a significantly better survival than nonresponders (P less than 0.05). Initial performance status was the only factor of demonstrable prognostic significance. Toxicity was similar to that observed in other phase II trials of adriamycin. Adriamycin, based on these data, is an active agent in the treatment of advanced or recurrent endometrial carcinoma.


VM-26, a new anticancer drug with effectiveness in malignant lymphoma: an Eastern Cooperative Oncology Group Study (EST 1474).

Thirty-six patients with stage III and IV Hodgkin's disease and non-Hodgkin's lymphoma, who had become refractory to conventional chemotherapy, were treated with VM-26. Complete remissions were documented in two patients with diffuse histiocytic lymphoma. Six patients (four with non-Hodgkin's lymphomas and two with Hodgkin's disease) had partial remissions. The overall response rate was 22% (eight of 36 patients). Hematologic toxicity was the most frequent dose-limiting toxicity. Nonhematologic toxic effects were mild and acceptable. This study demonstrates that VM-26 can produce tumor responses in refractory lymphomas. The Eastern Cooperative Oncology Group is currently planning two new phase II studies to incorporate VM-26 with other active new agents, one involving hexamethylmelamine and the other involving cis-dichlorodiammineplatinum(II).


Phase I evaluation of piperazinedione in patients with advanced cancer.

The effects of iv administered piperazinedione were studied in 28 evaluable adult and eight evaluable pediatric patients with advanced cancer. Piperazinedione produced predictable myelosuppression of moderate degree at dosages of 3--3.5 mg/m2/day X 5 days by iv injection. When given in this manner, nausea and vomiting did not occur. Single iv doses of 10--15 mg/m2 produced mild-to-moderate nausea and vomiting and mild myelosuppression. Thrombocytopenia was more severe than leukopenia in both schedules. The drug produced comparable dose-related effects in adults and children. Although no therapeutic response was observed in the adults, a partial remission of 6 months' duration was seen in one child with Hodgkin's disease.


Phase II study with sequential L-asparaginase and methotrexate in advanced refractory breast cancer.

The combination of sequential L-asparaginase and methotrexate (MTX) was evaluated in 33 patients with advanced refractory breast cancer. There were nine partial responses and one complete response, giving an overall response rate of 30% and a median duration of response of 8 months. Five of 17 patients (28%) who had received prior MTX at doses of less than 50 mg/m2 responded. Toxicity was acceptable. Moderate-to-severe stomatitis occurred in most patients and was the dose-limiting factor. Myelosuppression was minimal until the dose of MTX was escalated to greater than or equal to 180 mg/m2. The maximum tolerated dose of MTX was 280 mg/m2 and the median toxic dose was 220 mg/m2. These data indicate a selective "rescue" from MTX damage to normal target tissue by L-asparaginase. The antitumor effect observed even in patients who had been previously exposed to conventional doses of MTX suggests a possible improved therapeutic index of MTX given sequentially with L-asparaginase in this combination.


Right aortic arch, right patent ductus arteriosus, and mirror-image branching of the brachiocephalic vessels.

Two patients with a right aortic arch, right patent ductus arteriosus, and mirror-image branching of the brachiocephalic vessels are described. The clinical, angiographic, and surgical findings in these two cases are detailed, and a description of the embryologic basis for these anomalies is given.


Flow cytometric cell cycle analysis using the quenching of 33258 Hoechst fluorescence by bromodeoxyuridine incorporation.

Cultures of L cells were grown in medium containing 2.0 mg/l bromodeoxyuridine (BUdR) and stained with the fluorescent dye 33258 Hoechst for flow cytometric analysis. During exposure to BUdR, The cells replace thymidine by BUdR in the newly synthesized DNA. The new DNA is not stainable with 33258 Hoechst, which is highly specific for thymidine. The temporal development of the fluorescence distributions after addition of BUdR to the growth medium has been investigated in the flow cytometer, and the data were used to calculate the mean durations of the phases G1, S and G2 + M in exponentially growing cultures as well as the cycle transit times in synchronized cultures. The percentage of non-cycling cells was determined in each experiment.


Delay of cell cycle progression after X-irradiation of synchronized populations of human cells (NHIK 3025) in culture.

The effect of X-irradiation on the cell cycle progression of synchronized populations of the human cell line NHIK 3025 has been studied in terms of the radiation-induced delay of DNA replication and cell division. Results were obtained by flow cytometric measurement of histograms of cellular DNA content and parallel use of conventional methods for cell cycle analysis, such as pulse labelling with [3H]thymidine and counting of cell numbers. The two sets of methods were generally in good agreement, but the advantages of employing two independent techniques are pointed out. Irradiation was found to have a minor influence on DNA replication. As compared with unirradiated populations, half-completed DNA replication was 20--30 min delayed in populations 580 rad in mid-G1 or 290 rad in early S. Cell cycle progression was markedly delayed in G2. The sensitivity induction of this delay was 0.6 min/rad for populations irradiated in mid-G1, and 1.4 min/rad for populations irradiated in early S.


In vitro transcripts from the rrn B ribosomal RNA cistron originate from two tandem promoters.

The functional structure of the promoter region of a bacterial ribosomal operon is analyzed by in vitro transcription of linear DNA fragments derived from the hybrid Col EI plasmid pGG1. This plasmid contains the promoter region of the rrn B ribosomal cistron present in the lambdarifd18. When transcripts arising from this promoter region are terminated by restriction endonuclease cleavage of DNA, two RNA chains are resolved by gel electrophoresis that differ in length by about 100 bases. Evidence is presented indicating that these two transcripts arise from different initiation sites, each directing tandem transcription on the sense strand of the early portion of the ribosomal cistron.


Mu insertion duplicates a 5 base pair sequence at the host inserted site.

Nucleotide sequences were analyzed across the two ends of lysogenic Mu DNA. These ends were cloned separately in lambdapMu hybrid particles that derived from a single Mu lysogen in the lac Z part of lambdaplac5. The obtained data imply that Mu lysogenization was associated with the duplication of 5 base pairs present in lac DNA at the Mu insertion site. As a result of this duplication, Mu DNA is flanked by two copies of five identical base pairs oriented as direct repeats. A similar conclusion has been obtained independently by other investigators with the use of a different Mu lysogen (D. Kamp and R. Kahmann, personal communication). Thus Mu insertion seems to have a striking similarity to typical IS-mediated insertions that were found to be associated with a short DNA duplication at the target site.


Antibodies against chromosomal HMG proteins stain the cytoplasm of mammalian cells.

Antibodies specific to protein HMG-1 were purified by affinity chromatography on Sepharose columns to which HMG-1 was covalently bound. Immunofluorescence studies with these antibodies reveal that HMG-1 or components which immunologically cross-react with HMG-1 are present in the cytoplasm of Chinese hamster V-79, rat liver TR-12 and bovine trachea EBTr-NBL-4 cells. At selected antibody concentrations, the fluorescence present in the cytoplasm is more intense than that observed in the nucleus. The presence of HMG-1 protein in the cytoplasm of rat liver cells was verified by direct examination of the protein content of selected cytoplasmic fractions. A protein with electrophoretic mobility identical to HMG-1 was detected by electrophoresis on polyacrylamide gels containing either sodium dodecylsulfate or urea. Furthermore, the cytoplasmic extracts yielded a positive complement fixation with anti-HMG-1, while no reaction was obtained with control anti-H1 sera. We suggest that HMG protins, rather than functioning in the nucleus alone, are important structural elements of the entire cell.


Length-independent separation of DNA restriction fragments in two-dimensional gel electrophoresis.

When double helical DNA is exposed to conditions favoring partial melting in polyacrylamide gels, its electrophoretic mobility undergoes a sharp cooperative transition, resulting in a large reduction in mobility. In the present experiments, where the transition is effected at a uniform temperature of 60 degrees C in a concentration gradient of a urea-formamide mixture, each Eco RI fragment of lambda or E. coli DNA exhibits the mobility transition at a characteristic concentration of the denaturant. The sudden retardation of fragments moving toward higher denaturant concentration in the gradient results in a pattern of sharpened zones in order depending upon nucleotide sequence, rather than size, and only very slightly dependent upon the time after the last fragment has been retarded. When combined with length-dependent electrophoresis in agarose in the perpendicular direction, this system provides a two-dimensional separation of fragments. The resolving power of the system is demonstrated by the clear resolution of over 250 fragments of the Eco RI digest of E. coli DNA. Corresponding fragments from an isogenic lambda lysogen of E. coli are found in the same positions, and additional fragments unique to the lysogen are evident.


The participation of alpha-actinin in the capping of cell membrane components.

By means of double fluorescence staining experiments, intracellular alpha-actinin was found to accumulate under caps and patches induced in several cells by a variety of ligands. This phenomenon was demonstrated in lymphocytes and lymphoma cells treated with anti-H-2 sera; spleen lymphocytes treated with concanavalin A or anti-immunoglobulin antibodies, and VSV-infected mouse fibroblast line MC57 treated with antiserum against viral antigens. It occurred during both rapid and slow capping processes, and could be obtained by either direct or indirect ligand-induced redistribution. These observations were carried out on whole cells. For other cytoskeletal proteins such as filamin, tropomyosin and myosin, a similar accumulation under caps was not readily apparent using whole cell mounts, although earlier experiments with frozen-sectioned cells had shown such an enrichment of myosin (as well as actin). The enrichment of alpha-actinin under the clustered surface molecules was already apparent in early stages (patching) of the capping process, with or without 10 mM sodium azide present. Prolonged incubation of the cells with the different ligands resulted in endocytosis of the ligand-receptor complex. alpha-Actinin was not associated with the inernalized complex, however, suggesting that it may dissociate from the patched or capped surface structures at some stage during endocytosis.


The activity of chloroquine against plasmodium falciparum in Bandar Abbas, Southern Iran, 1976.

Study to monitor the susceptibility of P. falciparum to chloroquine in south Iran was conducted in Bandar Abbas. Forty-five falciparum malaria subjects who had received 25mg. chloroquine base per kg. body weight over 3 days were followed up for 4 weeks, while three other patients for a period of 1-3 weeks. No recrudescence could be confirmed among the subjects during the follow up of the study. The mean time of asexual parasites clearance was 2.15 days. The action of chloroquine against the asexual form of P. falciparum in the present study was suspected to be slower as compared with those observed in the previous studies. However, both in vivo and limited study using the in vitro technique showed that the response of P. falciparum asexual parasites to chloroquine was still satisfactory. The study supports previous findings in Ethiopia that acquired immunity malaria had no significant effect on the asexual parasite clearance time.


[Toxoplasmosis in Eastern Gabon. Results of a serologic survey].

1,448 sera taken from individuals of various places of South-Eastern Gabon have been studied by means of indirect immunofluorescence and Fulton direct agglutination associated with 2-mercapto-ethanol test, 52.6% contained antitoxiplasmic antibodies. This study showed that toxoplasmic infection occurs early in both sexes, that it is more frequent in men (57.9%) than in women (45.4%), that the Ogooué-Lolo province is more contaminated (62.6%) than the High Ogooué province (49.6%). It seems that prevalence differences are less dependent upon the telluric elimate than upon other factors, which remain to find.


Flunisolide--a new intranasal steroid for the treatment of allergic rhinitis.

A double-blind, cross-over comparison of flunisolide nasal spray and its inactive aqueous vehicle has been carried out in fifty patients suffering from perennial allergic rhinitis. Patients were randomly allocated to two groups; the first group (group I) received flunisolide for 3 weeks and then placebo for 3 weeks while the regimes were given in the reverse order to the second group (group II). Patients used two insufflations of 0.1 ml in each nostril twice daily. As the active spray was presented as a 0.025% solution of flunisolide, the total daily dosage was 200 microgram. Patients were assessed on admission and at the end of each 3 week period. The results show flunisolide to be significantly superior to placebo in relieving sneezing, nasal obstruction and postnasal drip, as well as improving the quality of sleep and everday life. At the end of the trial the preferences for treatment recorded by both doctors and patients were significantly in favour of the flunisolide spray. Side effects were minor and occurred during both placebo and active phases of the trial. A short Synacthen test performed at each visit showed no evidence of adrenal suppression.


Another look at Daggett's 1948 tympanoplasty.

It is important that we look critically at the results of conservative tympanoplasty in the presence of cholesteatoma. Lessons and observations taught many years ago by earlier otologists may give us valuable leads. A method of conservative surgery for chronic suppurative ear disease devised by Dr William Daggett in London in the late 1940s is described and evaluated in the light of current technical expertise.


[The role of interhuman contacts in the transmission of cholera, epidemics of 1832 and 1854].

By mapping the evidence of excess mortality month by month for cholera epidemics of 1832 and 1854, which were the most deadly and most typical of their kind in France, the authors are able to provide a kinetic description of the propagation of the Asian disease throughout the whole of France. Traditionally it has been assumed that hydric anademia explains, for the most part, the paths taken by the disease and its varying intensity, but the importance of direct interhuman contamination is demonstrated by the similitude between the ways gone along by the propagation and these of the circulation of men and goods. The evolution in the structure and volume of commercial exchanges in the first half of the nineteenth century in France, may account for the fact new areas of propagation of disease appeared in 1854, pointing to an increase in mobility and the opening up of entire regions to trade. Nevertheless, the example of migrants from Paris to Guéret seems to show that the part of "healthy germ-carriers" in the contamination is very slight.


Reconstruction after pharyngolaryngo-oesophagectomy using delto-pectoral flap.

Fifty patients with hypopharyngeal cancer treated with total pharyngolaryngectomy and staged reconstruction using delto-pectoral flaps in the years from 1967-1976 were studied. The main complications were fistulae and stricture formation; these are described. The hospital mortality was low, and postoperative deaths only occurred in previously irradiated patients. The crude 5-year survival was 35%.


[A critical study of immuno-enzymatic reactions coupled with the precipitation tests on cellulose acetate membranes].

Precipitating tests carried out on cellulose acetate membrane can be increased by treating the immune complexes with enzyme linked anti-immunoglobulin antibodies. From our trials in parastic diseases (Amoebiasis, schistosomiasis, fasciolasis, filariasis, hydatidosis, trichinosis) and mycosis (Aspergillosis, Candidiasis), it seems that the immuno-enzymatic labelling of the "active" precipitating reactions should only be taken in consideration. We must insit on the importance of ELIEDA (enzyme-linked-immuno-electrodiffusion-assay) and ELIDEPA (enzyme-linked-immuno-double-electro-phoresis-assay). Both of these analytical assays are particularly sensitive. The sequence of appearance of the multiple precipitating systems of the complex parasitic mosaic can easily be watched. The different classes of immunoglobulins and their kinetics are determined by the use of monospecific antibodies linked to different enzymes which give a polychromic specific staining.


[Malaria caused by accidental inoculation. 1 case].

The authors report a case of direct infection of a nurse who had taken blood sample from a young patient suffering from malaria due to Plasmodium falciparum. Six similar observations have been reported in the literature. In addition, accidental infection has been observed following the use of non sterile syringes. As a result, malaria could be an unexpected consequence of the drug habit.


Gallstone dissolution--a progress report.

Cholesterol gallstone formation occurs in three stages. First, the bile must be saturated with cholesterol, thereby allowing cholesterol crystals to form. Then, nucleation and growth of the gallstone can occur, although little is known about these latter two stages. Therapy for dissolution of gallstones is directed at desaturating the bile. Chenodeoxycholic acid (CDCA), the most extensively tested agent, is successful in dissolving 60 per cent of radiolucent gallstones; however, long-term safety remains to be demonstrated. Ursodeoxycholic acid (UDCA), the 7 beta epimer of CDCA, is a promising agent for cholesterol gallstone dissolution, but it, other potential agents, and dietary manipulations require more extensive study. An important problem, the prevention of recurrence of gallstones after dissolution, also needs resolution. Medical dissolution probably will be applicable as an alternative to cholecystectomy for most patients with radiolucent gallstones, but the specific relative indications remain to be determined. A variety of modalities, both medical and surgical, are being used for the treatment of retained or reformed bile duct stones. These include T-tube infusions, oral CDCA, and extraction either through the T-tube tract or after endoscopic papillotomy. Further studies, including controlled trials, are necessary to determine the relative indications for these methods.


Supplemental nutrition and digestive disease.

Nutrition is an antegral part of medical management and patient care. The goal of nutritional therapy is to provide nutrients in form and amount appropriate to patients' needs. Dietary modification and application of available nutritional supplements in digestive disorders should be based upon an appreciation of the fundamental pathophysiological derangements and tailored to restore optimal gastrointestinal function.


Antidiarrhoeal agents and laxatives: changing concepts.

Recognition that altered intestinal electrolyte transport (decreased absorption and/or increased secretion) is a primary factor in many types of diarrhoea is shaping the search for new types of antidiarrhoeal agents; it also supports continuing interest in the time-honoured but still largely unproved adsorbents. Recognition that altered intestinal electrolyte transport is also a primary effect of certain of the laxatives is of less immediate practical significance, because of the appropriate emphasis on dietary fibre and other nonpharmacological measures for prevention and correction of functional constipation. However, interest in the laxatives and their mechanisms of action will probably be directed to unanswered problems in bowel motility and the pathogenesis of constipation, which could subsequently modify use of the laxatives.


Spleen scan in histiocytic lymphoma: response to therapy.

Spleen scan demonstration of space-occupying lesions in patients with histiocytic lymphoma is a sensitive but not a specific finding. However, response to therapy could be evaluated if pretreatment scans show well-defined space-occupying lesions and posttreatment scans showed resolution of those changes.


Septic arthritis mimicking cellulitis: distinction using radionuclide bone imaging.

Two patients originally diagnosed as having cellulitis involving the dorsum of the foot actually had bacterial arthritis of an underlying joint. In both patients, even after pyarthrosis was suspected, the wrong joint was aspirated. The arthropathies were located by subsequent 99mTc-phosphate bone imaging at a time when roentgenograms were normal. Early diagnosis and aggressive therapy of septic arthritis are essential to prevent joint destruction and osteomyelitis. Radionuclide bone imaging can identify inflammatory joint disease but it cannot specify etiology. In our patients, however, the differential diagnosis was between skin and joint infection. Radionuclide imaging was of great help in making this distinction.


The intracellular pathway for parathormone biosynthesis and secretion.

The initial translation product of parathormone messenger RNA--preproparathormone--is larger than parathormone. Two amino terminal peptide segments of the peptide chain are removed sequentially to form the 84-amino acid hormone. The first cleavage, the removal of a 25-amino acid extension from preproparathormone, occurs in the rough endoplasmic reticulum, and results in the formation of proparathormone. This peptide moves via an energy-dependent mechanism to the Golgi region of the cell where a specific converting enzyme cleaves a basic hexapeptide segment yielding parathormone itself. A part of the newly formed hormone then is enclosed within prosecretory vesicles, transported to the cellular membrane and secreted. Another portion is stored in mature secretory vesicles and is subject to subsequent secretion. The moment to moment control of parathormone secretion by calcium resides at the plasma membrane, but a tightly coupled response at the level of intracellular hormone degradation is also necessary in order to control intracellular hormone levels in the face of rapid changes in secretory rate. Three major secretory products are released from the parathyroid under the control of extracellular calcium: (1) parathormone, (2) a large protein--"parathyroid secretory protein"--whose function is unknown, and (3) peptide fragments of parathormone. Secretion of hormonal fragments adds to the population of parathormone immunoreactivity in the blood. These fragments appear to be similar if not identical to those formed by peripheral metabolism of parathormone in the liver and kidney.


Minimizing postsurgical scars.

You will want to minimize postoperative scars for your and your patient's satisfaction. There are operative procedures and suturing techniques that will help you but, ultimately, a fine result can be most often obtained by meticulous attention to each detail, from the prep through the planning, the execution of the procedure, and the postoperative care.


Fluocinonide vs halcinonide in atopic dermatitis. A paired comparison of two potent topical corticosteroids.

A study showing the superiority of fluocinonide (0.05 percent) cream over halcinonide (0.1 percent) cream in the treatment of atopic dermatitis is presented herein.


Clinical pharmacokinetics of oral anticoagulants.

Warfarin is clinically the most widely used oral anticoagulant and its properties have been extensively studied. Assay method for these compounds have until recently been relatively nonspecific. The advent of chromatographically based techniques has enabled re-evaluation of the pharmacokinetics of oral anticoagulants, but most work continues to involve warfarin. The most important recent work has concerned the different anticoagulant potencies and metabolic pathways of the optical isomers of some of these drugs. The effects of age and some diseases on pharmacokinetics of warfarin have been examined but much remains to be done, especially with oral anticoagulants other than warfarin. There are several well established pharmacokinetic drug interactions with warfarin. There is a wide awareness of the drugs most likely to reduce anticoagulant effects by enzyme induction and alternative drugs can be used. Mechanisms of some interactions have been re-investigated. In vivo drug displacement interactions are complicated by the correlation between hepatic clearance of these drugs and the size of the unbound fraction in plasma. The interactions between phenylbutazone and warfarin and metronidazole and warfarin, resulting in potentiation of anticoagulant effect have been suggested to be due mainly to an inhibition of the metabolism of the more potent S isomer of warfarin.


Thoracoscopy. Early diagnosis of interstitial pneumonitis in the immunologically suppressed child.

Interstitial pneumonitis in immunosuppressed patients demands prompt diagnosis and treatment. In an effort to achieve a simple yet highly accurate method of diagnosis, we have evaluated the usefulness of thoracoscopic examination. Twenty-seven procedures have been performed in 24 patients between the ages of 17 months and 18 years. All patients were immunosuppressed, most for treatment of malignant processes. All procedures have been performed under anesthesia with intravenously administered ketamine, without endotracheal intubation. A definitive diagnosis has been made in every case, with pneumonia due to Pneumocystis carinii being identified in 18 instances. Complications have been minimal and include four minor pneumothoraces, two instances of bleeding, and two instances of prolonged air leak. Mortality attributable to the procedure has been nil, although five patients have died due to their underlying diseases within 30 days of the thoracoscopic procedure. Thoracoscopy has proven to be a rapid and safe technique for providing accurate histologic and bacteriologic diagnoses in these critically ill children.


Bilateral diaphragmatic paralysis in the newborn infant: treatment with nasal continous positive airway pressure.

A newborn infant with severe respiratory distress from bilateral diaphragmatic paralysis caused by birth injury was successfully treated with nasal continuous positive airway pressure (CPAP). Improvement gradually occurred, and CPAP was discontinued after he was 23 days of age. This therapy has advantages over alternative methods.


The recovery period following exposure of bacteria to penicillins.

Experiments with Staphylococcus aureus and Streptococcus pyogenes have shown that when cells are exposed to bactericidal concentration of benzylpenicillin or ampicillin and the antibiotic then inactivated with beta-lactamase the count of the surviving viable cells (colony-forming units) remains essentially constant for a period of approximately 1.5--3 h before increasing at a normal rate. No such recovery period was observed, however, when Escherichia coli or Proteus mirabilis was exposed to a bactericidal concentration of ampicillin and the antibiotic then inactivated. Microscopic observation of individual surviving cells of S. aureus following exposure to benzylpenicillin showed that in some cases resumption of cell division was delayed as long as 4 h. However, other cells in the same population showed no recovery period and resumed division within 30 min of inactivation of the antibiotic. In the latter case, the recovery period which is observed in terms of viable count may represent the period of time required for individual surviving cells to divide and give rise to normal aggregates before these fragment to produce new colony-forming units.


In vitro activity of sulphonamides as a function of their molar refractivity.

A significnat correlation has been found between the in vitro activity of 16 commonly employed sulphonamides and their molar refractivity. The molar refractivity has been shown to be a superior parameter for the description of the activity of sulphonamides than the sum of electronegativities of atoms making up a heterocyclic substituent in the sulphonamide molecule and molecular weight of the substituent.


[Transmural varices ligation and fundoplication as an emergency operation in acute esophageal varices hemorrhage].

In patients with bleeding esophageal varices the main purpose of the treatment is to stop the bleeding at a justifiable risk. The so-called blocking procedures reach this purpose most consistently. We report the results on transmural variceal ligation plus fundoplication in 16 patients in whom the bleeding esophageal varices were not stopped by conservative means. 75% of these patients belonged to group B and C in Child's classification. Postoperative lethality was 18,7%, in all cases bleeding was stopped. These results favour trasmural varices ligation as an emergency procedure in bleeding esophageal varices.


[Treatment of hemorrhage from acute gastric and duodenal mucosa lesions with secretin].

In a prospective study 67 patients with bleeding from acute gastric mucosal lesions were treated by intravenous infusion of secretin. In 64 of the 67 patients bleeding stopped during secretin infusion. In 16 of these 64, bleeding recurred after cessation of the secretin infusion; all recurrences were stopped by secretin. Severe side effects were not observed. Secretin seems to be an effective drug in the treatment of stress ulcer bleeding.


[Continent colostomy through free transplantation of autologous colon muscles].

The study is concerned with a problem which is to a great extent still surgically unsolved, namely that of the incontinent hollow organ occlusion. We report on our own experiments on animals and on physiologicofunctional studies, which reveal the suitability of the smooth muscles as an ideal material for sphincter replacements. By histologic research it became obvious that autotransplantations of smooth muscles, carried out for the first time by the Department of Surgery of the University of Würzburg, are possible without significant tissue changes. The transplant is soon supplied by vessels which sprout ubiquitously and completely permeate it so that it can take over its function as sphincter. Meanwhile, the experience gained in experiments on animals has been transferred to surgery on humans. Incontinence and incontinence of the preternatural anus were eliminated in the first operations using autologous autotransplanted sphincteroplasties.


[Present-day serological diagnosis of syphilis: comparison of TPHA and FTA-ABS tests with classical flocculation and complement-fixation reaction (author's transl)].

Twelve laboratories in the north Rhine-Westphalia participated in comparing TPHA and FTA-ABS tests with the so-called classical syphilis reactions (VDRL test, cardiolipin and pallida complement-fixation reaction, as well as Meinicke clearing reaction II). TPHA and FTA-ABS tests proved to be superior to the conventional methods both as regards specificity and sensitivity. Present-day serological tests of syphilis can thus be limited to the TPHA test to exclude syphilis, the FTA-ABS test as a confirmatory reaction and the VDRL test to judge the need or effectiveness of antisyphilitic treatment. These reactions which supersede the conventional syphilis tests serve for rational, reliable and cheap serological diagnosis of syphilis.


Timolol: a review of its therapeutic efficacy in the topical treatment of glaucoma.

Timolol maleate is a nonselective beta-blocking drug used for the topical treatment of increased intraocular pressure in patients with chronic open angle glaucoma. In comparative studies it has had a somewhat greater ocular hypotensive effect than the sympathomimetic agent adrenaline (epinephrine), or lower to medium concentrations (up to 4%) of the miotic drug pilocarpine, usually lowering intraocular pressure by about 30 to 35% (absolute pressure reduction). Timolol has been well tolerated by most patients, producing fewer subjective complaints than the comparison drugs, and objective measurements of ophthalmic status have not revealed any marked changes. Although some patients have been treated for extended periods without serious adverse effects or loss of effectiveness, further published reports in larger numbers of patients treated over several years are needed to confirm the drug's apparent long term safety and continued efficacy. Nevertheless, on the basis of present evidence, timolol appears to represent an important advance in the topical treatment of glaucoma.


Cefoxitin: a review of its antibacterial activity, pharmacological properties and therapeutic use.

Cefoxitin is a beta-lactam antibiotic derived from cephamycin C, a naturally occurring substance produced by Streptomyces lactamdurans. Its resistance to destruction by beta-lactamases results in a broad spectrum of antibacterial activity which includes anaerobic as well as Gram-positive and Gram-negative aerobic bacteria, including many resistant to cephalothin and other cephalosporins. Given by intravenous or intramuscular injection, cefoxitin is effective against a wide variety of infections caused by Gram-positive or Gram-negative aerobes as well as by anaerobic bacteria. It is generally well tolerated, thrombophlebitis, skin rash and some degree of discomfort after intramuscular injection, being the most commonly reported side effects. Cefoxitin has not been shown to cause adverse effects on renal function.


Effect of lithium on pancreatic islet insulin release.

Lithium exerts an inhibitory effect on glucose and amino acid-induced insulin release. The inhibitory effect of Li+ persists even in subsequent Li+-free conditions, indicating an only slowly reversible effect. Lithium fails to inhibit glucagon-induced insulin release. The exact mechanism of the lithium effect is as yet undetermined, but interference with calcium flux and/or microtubular function is an attractive hypothesis. The inhibitory effect of lithium on insulin release cannot be reversed by alteration in ionic (Ca++, Mg++, K+) concentrations in the incubation media. Studies involving the effect of low sodium on insulin release in which lithium had been used as an osmotic replacement for sodium must be carefully reassessed because of these findings.


Extrahypothalamic neurophysin-containing perikarya, fiber pathways and fiber clusters in the rat brain.

Immunoreactive neurophysin (Np) is demonstrated by the immunoperoxidase technique not only within neurones of the classical hypothalamo-neurohypophyseal system, but also in extrahypothalamic perikarya and fibers. Np-positive perikarya are found in the triangular nucleus of the septum. Np fibers join the stria terminalis (ST) at the level of the anterior hypothalamus, and course medially in the ST to the central nucleus of the amygdala. Np fibers are found in the brain stem and spinal cord. Fine caliber Np fibers from the suprachiasmatic nucleus ascend to the medial dorsal thalamus and lateral septum. The presence of Np within neurones implies the presence of either vasopressin or oxytocin. Np-positive fibers in extrahypothalamic sites may interact with non-neurosecretory neurones involved in neuroendocrine regulation, or may serve as yet unknown functions.


Longitudinal study on the establishment of insulin resistance in hypothalamic obese mice.

A longitudinal in vivo and in vitro analysis of the genesis of insulin resistance has been carried out in mice made obese by chemical made obese by chemical lesion (goldthioglucose, GTG) of the hypothalamus. Six weeks after GTG administration, glycemia and glucose disposal were normal but associated with increased insulin concentration, suggesting incipient insulin resistance. The in vitro counterpart of the latter in obese mice was observed in soleus muscle that was somewhat less responsive to insulin than controls, in liver that had increased basal lipogenesis but was uninfluenced by insulin, and in hepatic plasma membranes in which a slight decrease of insulin binding was measured. At this stage of obesity, basal adipose tissue lipogenesis was increased but the tissue responded in a normal fashion to insulin. These relatively discrete early metabolic changes were corroborated in vivo by a normal hypoglycemic effect of exogenous insulin. Sixteen weeks after GTG administration, hyperglycemia and gross hyperinsulinemia were recorded. This insulin resistance was evidenced in vivo by the lack of hypoglycemic effect of exogenous insulin unless considerable amounts of the hormone were administered. It coincided in vitro with a poor response of soleus muscle to insulin, an absence of a stimulatory effect of the hormone upon both adipose tissue and liver tissue, and a marked decrease in insulin binding to liver plasma membranes. It appears that insulin resistance is a multifactorial and progressive abnormality that might involve both insulin receptor and intracellular metabolic alterations.


Phorbol myristate acetate: effect of a tumor promoter on insulin release from isolated rat islets of Langerhans.

Phorbol myristate acetate (PMA), a tumor-promoter capable of influencing biologic functions of many cell systems, has been demonstrated to augment glucose-initiated insulin release from isolated rat islets of Langerhans. PMA caused a 2-fold increase in insulin release. This effect of PMA did not alter the sigmoidal relationship of insulin released to glucose concentration. The effect of PMA on insulin secretion from the islet beta-cells persists and a challenge with glucose alone, subsequent to a pulse of PMA, elicits an augmented insulin release response.


Changes in plasma luteinizing hormone-releasing hormone and gonadotropin concentrations during constant rate intravenous infusion of luteinizing hormone-releasing hormone in cyclic rats.

Further analysis has been made of the response of the rat pituitary gland to LHRH during the 4-day estrous cycle. LHRH was infused iv at a constant rate (50 ng/h) into phenobarbital-treated rats at different times during the estrous cycle. Infusion at this rate in proestrous rats simulates the rising and plateau phases of the spontaneous proestrous surges of LH and FSH in plasma. Plasma LH rose to similar heights during the "initial phase" of LH release (during the first 40 min of infusion) on the afternoons of estrus, diestrous day one, and proestrus and during the morning of proestrus. The increase during the afternoon of diestrous day two was significantly less than that in all the other groups. A similar response was seen in the case of FSH release. A "rapid rising" or "augmented" phase of LH release (during 40-120 min of infusion) was present in all groups and the magnitude of the response was greatest during the afternoon of proestrus. In the case of FSH, an augmented phase of release started 60 min after the start of infusion, and the response during the afternoon of proestrus was slightly greater than the responses measured at the other times tested. The responses on diestrous day one were not altered when phenobarbital was omitted or when rats were ovariectomized shortly before LHRH infusion. Other differences in the LH and FSH responses during both initial and augmented phases of release were seen in rats tested at different times during the estrous cycle with an LHRH infusion rate which caused a supraphysiological response on proestrus. The results suggest that 1) the initial rising phases in plasma LH and FSH during the spontaneous surges during proestrus are not the result of an increase in pituitary responsiveness to LHRH during the estrous cycle, 2) augmented phases of LH and FSH release can be elicited on all days of the estrous cycle, and 3) the increases in magnitude of the augmented phases of LH and FSH release on proestrus, as compared to those on other days of the cycle, are the result of an increase in pituitary responsiveness to LHRH during the estrous cycle.


Studies on the dual effects of glucose on 45Ca++ efflux from isolated rat islets.

45Ca++ efflux studies were performed on rat islets of Langerhans which were loaded to isotopic equilibrium during 48 h in tissue cultures. 45Ca++ loading was 50% complete at 1 h, 80% at 4 h, and reached, at equilibrium, a content equal to 10-11 pmol/islet. The islets responded to glucose stimulation with a rapid and markedly biphase insulin release. Under normal conditions, glucose stimulated 45Ca++ efflux with an initial surge (simultaneous with the first peak of insulin release), which declined rapidly to 50% of the peak value and then slowly declined for the remainder of the glucose stimulation. Special conditions were required to uncover an early inhibition of 45Ca++ efflux; these were the lowering of the temperature of the perifusate from 37 C to 30 C or below, or reduction of the medium Ca++ concentration to 0.1 mM or less. Under zero calcium conditions the glucose inhibition of 45Ca++ efflux can be rigorously interpreted as an inhibition of calcium efflux. The studies at low temperature or low Ca++ concentrations revealed two effects of glucose on 45Ca++ efflux: an initial inhibition followed by a stimulation, the inhibitory effect was obscured by the rapidity of onset of the stimulatory effect under normal conditions. At low temperature it was also possible to inhibit glucose-stimulated insulin release, although the stimulated 45Ca++ efflux remained unchanged. At 30 C or in experiments with 0.3 mM Ca++, glucose-stimulated insulin release preceded the stimulation of 45Ca++ efflux. It therefore, is, concluded that the stimulated 45Ca++ efflux is a consequence, rather than a determinant, of stimulus-secretion coupling. The stimulated efflux is dependent on the presence of Ca++ in the medium and is independent of emiocytosis. This latter finding excludes the secretory granules as a significant source of glucose-stimulated 45Ca++ extrusion.


Electrical responses of rat islets maintained in culture with varying levels of glucose.

The electrical responses of rat islet cells maintained in culture with varying levels of glucose were determined. After culture with 2.8 or 4.2 mM glucose, the beta-cells did not respond electrically to 27.8 mM glucose. However, after culture in 5.6 mM glucose, the cells responded to 27.8 mM glucose in short term experiments with depolarization and an increase in the incidence of spike activity. Islet cells maintained in 8.4 or 14.0 mM glucose had increasingly greater (negative) membrane potentials. The incidence of glucose-induced spike activity was the greatest for cells which had been cultured in 14.0 mM glucose. Raising glucose in the culture medium from 2.8 to 14.0 mM for the last 2 days of culture restored the ability of the islets to respond electrically to glucose in short term experiments. These observations show that the electrical phenomena of the beta cell membrane are affected by alterations in the level of glucose in the culture medium and serve as reliable indicators of functional glucose sensitivity of the islet cells.


Modulation by alloxan of glucagon and insulin secretion in the isolated perfused rat pancreas.

The acute in vitro effect of alloxan on glucagon and insulin secretion from the isolated perfused rat pancreas was examined. Alloxan alone produced transient insulin secretion. Pretreatment with alloxan attenuated both the stimulatory effect of glucose on insulin secretion and the inhibitory effect of glucose on glucagon secretion. Exposure to alloxan in varying doses either partially or completely inhibited insulin secretion induced by arginine in the presence or absence of glucose. On the contrary, pretreatment with alloxan produced complex effects on arginine-induced glucagon secretion. In the absence of glucose, the response of glucagon to arginine infusion was lower in the pancreas exposed to alloxan than in the control experiment. In the presence of glucose, however, an apparently augmented response of glucagon to arginine was observed after exposure to higher doses of alloxan, suggesting an impaired inhibitory effect of glucose on arginine-induced glucagon secretion. These effects of pretreatment with alloxan on glucagon secretion can not be explained by earlier or simultaneous insulin secretion. Therefore, we conclude that alloxan acts not only on beta-cells, but also directly on alpha-cells, although the latter are less sensitive to this agent.


Somatostatin biosynthesis occurs in pancreatic islets.

No information is at present available on the mode of SRIF biosynthesis. Since anglerfish pancreatic islet tissue is comprised of approximately 30% D cells, we have examined this tissue for SRIF synthesis . The following known differences in amino acid composition of islet peptides were used advantageously in this study: anglerfish proinsulin: Trp-0, Ile-2, Cys-6; anglerfish glucagon: Trp-1, Ile-0, Cys-0; mammalian SRIF: Trp-1, Ile-0, Cys-2. After incubating islet tissue with [3H]tryptophan and [14C]isoleucine or [35S]cystine for various time periods, proteins were extracted in 2 M acetic acid and desalted by Bio-Gel P-2 gel filtration. P-2 void volume proteins were then subjected to P-10 gel filtration and isolated by polyacrylamide gel electrophoresis (PAGE) at alkaline pH. The predominant amount of the immumoreactive SRIF in the extracts appeared in a peak eluting just before the salt volume on P-10 filtration and migrated slowly toward the cathode during PAGE. The behavior of synthetic SRIF was identical. The anglerfish SRIF immunoreactive peptide could be labeled with Trp and Cys but not Ile during incubations longer than 1 h. The Trp- and Cys-labeled peptide could be bound on columns to which the immunoglobulin fraction of antisera to SRIF had been complexed. Cycloheximide inhibited isotope incorporation into all islet proteins. These results indicate that islet SRIF is synthesized in situ. Moreover, the immunological activity, size, and charge characteristics of anglerfish islet SRIF appear to be similar to those of mammalian hypothalamic SRIF. When islets were subjected to short pulse incubations with labeled Trp and Cys, only peptides eluting in the 7,000-13,000 dalton portion of the filtration eluate became labeled. No appreciable isotope incorporation into SRIF was observed. However, when pulse incubations were followed by incubation in the presence of cycloheximide or excess unlabeled amino acids in isotope-free medium (chase), the incorporation of Trp and Cys into SRIF increased with the length of chase, suggesting the participation of a larger precursor in SRIF synthesis.


Alloxan uptake by isolated rat islets of Langerhans.

Alloxan inhibits subsequent glucose-induced insulin release from isolated rat islets of Langerhans maintained in vitro. Several agents (D-glucose, D-mannose, 3-0-methyl-D-glucose, caffeine, and cytochalasin B) when present during the alloxan exposure protect against alloxan inhibition of insulin release. To examine the mechanism of alloxan inhibition, the uptake of [2-14C]alloxan was measured in isolated islets. [2-14C]Alloxan was rapidly accumulated by the islets in a time- and temperature-dependent manner. The radio-activity from islets incubated with [2-14C]alloxan was isolated and shown by thin layer chromatography to comigrate with alloxan and alloxanic acid, an alloxan decomposition product. As no uptake of radioactivity occurred in the presence of medium containing the radioactive decomposition product, it was concluded that alloxan enters the intracellular space of the islet and undergoes a subsequent internal decomposition. Some of the protective agents (3-0-methyl-D-glucose, caffeine, and cytochalasin B) partially inhibited alloxan uptake, whereas others (D-glucose and D-mannose) increased the uptake of alloxan. These and other results suggest that the experimental agents do not provide protection against alloxan inhibition by preventing the entry of alloxan into the intracellular space of the islet. The possibility of D-glucose and alloxan competing for a common binding site on the cell membrane is discussed.


Further studies on the relationship between insulin release and lanthanum-nondisplaceable 45Ca2+ uptake by pancreatic islets: effects of fructose and starvation.

Relationships between the release of insulin and the incorporation of 45Ca2+ into a lanthanum-nondisplaceable (intracellular) pool were studied in islets microdissected from the pancreatic glands of non-inbred ob/ob mice. In comparison with D-glucose, D-fructose was slowly oxidized and had only marginal effects on insulin release. However, fructose was as effective as glucose in stimulating the lanthanum-nondisplaceable 45Ca2+ uptake. The 45Ca2+ uptake was dose-dependent on the concentration of fructose in the range 0-20 mM; the same dose-dependence was obtained with glucose. Fasting the mice for 3 days caused a total block of the insulin secretory response to 20 mM glucose, but it produced an enhancement of the glucose-induced 45Ca2+ uptake. Both the inhibition of insulin release and the enhancement of 45Ca2+ uptake were counteracted by pretreating the isolated islets with 20-40 mM D-glucose; pretreatment with L-glucose or fructose could not counteract the effects of fasting. Although some functional relationship may exist between the lanthanum-nondisplaceable uptake of 45Ca2+ and the insulin secretory apparatus, it is concluded that the uptake of Ca2+ is not simply the result of stimulated insulin release.


Relation of biogenic amines to onset of puberty in the female rat.

Changes in hypothalamic concentration and turnover index (TI) of norepinephrine (NE), dopamine (DA), and serotonin (5HT) were studied during the first estrous cycle at the onset of puberty. Rats were killed when 40% of the population showed open vaginas. They were classified according to the state of their reproductive tract and serum LH values, as in anestrus, early proestrus, late proestrus, estrus, or diestrus. Serum LH, PRL, and hypothalamic LHRH were measured by RIA. The TIs for DA and NE were measured by estimating their rate of decrease after administration of alpha-methyl-para-tyrosine, and for 5HT-TI by its increase after pargyline administration. An increase in NE-TI in the hypothalamus was observed between anestrus and early proestrus, a decrease in DA-TI during early and late proestrus, and a small increase in 5HT-TI between early and late proestrus. LH and PRL peaks were observed at late proestrus when DA-TI and NE-TI reached their lowest values and hypothalamic LHRH concentration was failing. After late proestrus, the DA-TI rose sharply, NE-TI remained essentially unchanged. 5HT-TI fell, and serum LH and PRL declined to basal levels. These results suggest that the LH and PRL surges at late proestrus during the first estrous cycle at puberty are associated with an increase in NE-TI at early proestrus, a progressive decline in DA-TI at early and late proestrus, and an increase in 5HT-TI at late proestrus.


Presence of sulfhydryl groups in glucagon secretion granule membranes.

The effect of various sulfhydryl-binding reagents on the release of glucagon from isolated secretion granules was studied. Secretion granules isolated from toadfish islet tissue by differential centrifugation in sucrose were incubated in the test medium, the granules were centrifuged down, and the supernatant was assayed for glucagon using a RIA. When the granules were incubated in isotonic saline, 16-18% of the total glucagon in the granules was released. Whereas the addition of various dithiol-binding reagents (Cd++, Hg++, AsO2-, and dichlorophenylarsine), an oxidizing agent (oxidized glutathione), a reducing agent (reduced glutathione), and an amino group-binding reagent reagent (trinitrobenzene sulfonic acid) had no effect, the addition of Co++ to the incubation medium decreased glucagon release and the addition of the monothiol-binding reagents, p-hydroxymercuribenzoate and diphenylchloroarsine, produced a 2- to 3-fold increase in glucagon release. These results suggest that sulfhydryl groups may be present in the glucagon secretion granules and that they may be involved in glucagon release.


Inhibition of spermatogenesis in the rat by treatment with [D-Ala6, Des-Gly-NH210] LHRH ethylamide.

The effect of treatment with a potent LHRH agonist, [D-Ala6, Des-Gly-NH210]LHRH ethylamide, injected at the low dose of 100 ng, twice a week, was evaluated on spermatogenesis in the rat. Significant degenerative changes of seminiferous tubules could be observed after two weeks of treatment. These changes were progressive and led to a marked inhibition of spermatogenesis after four to eight weeks of treatment. Testis weight was decreased to approximately 50% of control after eight weeks of treatment.


Inhibition of de novo synthesis of FSH by the Sertoli cell factor (SCF).

The effects of SCF, a substance produced by isolated rat Sertoli cells in culture, on the synthesis of FSH and LH were studied in vitro. Anterior pituitaries from adult male rats were organ-cultured 24-48h in the presence and absence of SCF in the culture medium. The incorporation of 3H-leucine into FSH and LH was determined following 6h incubation with this labelled precursor and immunoprecipitation with specific FSH or LH antibodies. Total FSH and LH were measured by radioimmunoassay. The results indicate that SCF can selectively reduce the incorporation of 3H-leucine into immunoprecipitable FSH without decreasing the incorporation into LH.