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At least 1,405 records · Page 78Linked to original sources
PubMed1979

Vascular basophilia in ocular and orbital tumors.

The occurrence of vascular basophilia in ocular tumors has been a selective histologic feature of retinoblastomas. We recently observed a metastatic oat-cell carcinoma to the choroid which also demonstrated such a vascular hematoxyphilia. Histologic review of a variety of ocular and orbital metastatic carcinomas failed to yield a similar basophilic pattern. Examination of 100 consecutive retinoblastomas for vascular basophilia revealed an incidence of 6.0%. Similar material was not seen in any of 125 melanomas, including 10 with areas of necrosis. Histochemical studies showed the basophilic material to be DNA, and electron microscopy revealed the nuclear debris of pyknotic tumor cells to be continuous with identical material surrounding the adjacent blood vessels. The pathogenesis of vascular deposition of DNA in these two ocular tumors remains unclear. This finding most likely represents a form of tumor activity requiring comparatively healthy blood vessels to adequately precipitate liberated nucleic acids being filtered from the necrotic and degenerating tumor tissue.

Basophils↗
PubMed1989

Amphiphilic derivatives of betaine esters as modifiers of macrovesicular BLM.

A series of amphiphilic derivatives of betaine esters (V-n), with the chemical structure (CH3)3N+COOCnH2n + 1Cl- (n = 10, 12, 14 or 16) were studied with respect to their effects on the electrical properties of lecithin macrovesicular membranes. Normalized resistance and breakdown voltage were found to depend on the V-n concentration in the membrane and on the alkyl chain length (n). Resistance decreases up to about 10(4) ohm.cm2 and breakdown voltage decreases by 111 mV were detected in the V-n: lecithin molar ratio range measured (0.005-0.05). Maximal decrease in breakdown voltage was observed for V-14. These findings together with the featured anionic selectivity suggest that, due to the interaction of V-n with phospholipids, hydrophilic pores are formed in the lipid bilayers. This assumption is supported by the results obtained by electron paramagnetic resonance (EPR) measurements which showed no collective changes in bilayer dynamics or ordering. In particular, rotational correlation times and order parameters of the spin probe molecules dissolved in the membrane did not change in the concentration range tested. Since a large number of defects in the membrane can be expected to influence the collective ordering and dynamics, this observation also suggest that the number of pores formed is small.

Betaine↗
PubMed1985

[Rotavirus infections in childhood: studies using a molecular biology method (gene electrophoresis)].

During a 15-month period all children below 16 years admitted to the Children's Hospital in St. Gallen with acute diarrheal disease were studied for rotavirus (RV) infection. Stool samples from control patients without gastrointestinal disease were investigated for RV shedding in order to detect RV carriers or asymptomatically infected children. RV was detected by electrophoresis of RV genomic dsRNA in 154 children. 119 (58%) of 205 patients hospitalized because of diarrhea were RV associated, 25 children became symptomatically ill during their hospitalization, and in 10 (1%) of 954 control patients RV could be found. During the winter 1983/1984 two epidemic peaks of RV associated diarrhea were noted, whereas in the summer period RV related disease occurred only sporadically. The peak incidence of RV infection was in the age group between 10 and 12 months. After the 3rd year of life RV infection only rarely required hospitalization. During this study period 8 different genomic RNA patterns of RV were found. The number of patients within these 8 RV types, however, is too small to allow definite correlations between epidemiological or clinical features and selected electrophorotypes. The possibility to perform refined epidemiological and clinical analyses of RV infection by genomic dsRNA electrophoresis offers important advantages when compared to other RV detection systems. In addition, this method has proven to be fast, simple and reliable.

Adolescent↗
PubMed1987

Functional alterations of macrophages in autoimmune MRL-lpr/lpr mice.

To assess the role of macrophages (MAC) in the pathogenesis of systemic lupus erythematosus, we investigated functional aspects of peritoneal MAC obtained from autoimmune MRL/MpJ-lpr/lpr (MRL-lpr) mice. MRL-lpr and control C3H/HeN MAC were obtained from untreated mice or mice injected i.p. with 1 ml of 10% sterile peptone 3 days before cell harvest. MRL-lpr mice had significantly more peritoneal cells (MAC and lymphocytes) than did control mice. In endotoxin-free conditions, MRL-lpr MAC were similar to C3H/HeN MAC in their baseline, and IFN-gamma and/or LPS enhanced cytolysis of 3T12 fibrosarcoma tumor cells. Compared with C3H/HeN MAC, MRL-lpr MAC had a significant increase in antibody-dependent cellular cytotoxicity activity against sheep erythrocytes. This enhanced activity was not accompanied by a similar increase in adherence and/or phagocytosis of the same targets. Finally, in response to phorbol myristate acetate stimulation, both resident and peptone-induced MAC from MRL-lpr mice produced significantly more hydrogen peroxide than did those from control mice. These results indicate that MAC from MRL-lpr mice display features of selective "activation", and suggest that MAC or their products may play a role in the pathogenesis of inflammatory disorders seen in autoimmune diseases.

Animals↗
PubMed1986

Absolute and allometric relationships between internal morphology and body mass in the adult collared peccary, Tayassu tajacu (Tayassuidae).

Selected morphological features of 8 adult male and 8 adult female collared peccaries (Tayassu tajacu) shot from southern Texas during March 1983 are described. A total of 16 adult peccaries with an average body mass of 18.68 +/- 0.61 (SE) Kg was examined. Significant differences between males and females were observed for absolute and relative mass of liver and lungs, and relative heart mass. These visceral organs were heavier among females than males. Significant sex effects were also found for absolute and relative mass of the dorsal scent gland. The dorsal scent gland contributed twice as much to total body mass in males as in females. No sexual dimorphisms of the gastrointestinal tract were noted. Females had a significantly greater portion of total visceral fat deposited around the kidneys than did males. Relative mass of the mandible was significantly greater in males than in females. Adult males had extremely large accessory sex glands. The bulbourethral and seminal vesicle glands comprised 0.27 per cent of the total body mass. Allometric growth coefficients (b) varied among the various organs and glands examined, ranging from below (eyes, b = 0.34) to well above (seminal vesicles, b = 1.87) unity. Growth coefficients of lungs, kidneys, pituitary gland, and thyroid gland during adulthood greatly exceeded respective values in developing nurslings.

Adipose Tissue↗
PubMedDate not supplied

New drugs for treatment of ventricular arrhythmias.

This article has attempted to review selected clinical features of new antiarrhythmic agents for treatment of recurrent ventricular tachycardia and ventricular fibrillation. While it is apparent that the ideal antiarrhythmic agent does not exist, whether it be a new or old antiarrhythmic drug, effective and safe antiarrhythmic drug therapy can nevertheless be administered to many patients if the pharmacologic principles and properties described herein are carefully considered.

Amiodarone↗
PubMed1978

Myeloid bodies in the renal tubules of humans: relationship to gentamicin therapy.

Ultrastructural changes in renal proximal tubule lysosomes, including the formation of myeloid bodies, occur reliably with gentamicin administration in experimental animals. The present study reviewed the electron microscopic tubular morphology of renal biopsies and nephrectomies performed in our institution over a 2-year period. The frequency of myeloid bodies and their relation to drug therapy and selected clinical features were determined. Myeloid bodies were found in the proximal tubules of 19 of 109 cases that were judged adequate for study. On review of the drug histories of these 19 patients, 15 had received gentamicin within 6 weeks of biopsy or nephrectomy. None of the 90 patients without myeloid bodies had received the drug within 6 weeks of tissue examination. Of 4 patients with myeloid bodies who had not received gentamicin, 1 had received chloroquin and 3 had received drugs with no known or suspected capacity to induce myeloid bodies. The presence of myeloid bodies in proximal tubules did not appear to be related to the total dose of gentamicin, duration of therapy, or serum drug concentration. Clinical evidence of gentamicin nephrotoxicity was present in only 1 case.

Adolescent↗
PubMed1980

[Reliability of statistical methods in anthropology].

Univariate and multivariate statistical methods are confronted as to their efficiency and objectivity. Similar to the comparison of patients showing chromosomal aberrations or serious diseases with their normal controls, the investigation of various populations can only result in the determination of differences on the basis of features arbitrarily selected, but not in a classification of systematic categories. Objections as to the objectivity of statistical procedures in the field of racial classification are discussed.

Anthropology↗
PubMed1995

Incidence of thoracic outlet syndrome on the epidemiology and clinical presentation of apparently primary Raynaud's phenomenon. A prospective study in 570 patients.

In the absence of established criteria enabling a Raynaud's phenomenon to be related to a thoracic outlet syndrome, the authors attempted to assess whether the presence of objective clinical features of thoracic outlet might modify the epidemiology or the clinical presentation of Raynaud's phenomenon (RP). From a population of 570 RP, 263 RP with primary feature were selected according to classical clinical, biological and capillaroscopy criteria. Within this group, apparently primary RP without any objective sign of thoracic outlet were compared with those presenting objective signs of thoracic outlet (ie positive "candlestick manoeuvre", abnormal dynamic Doppler examination). The two groups were compared according to epidemiologic (family history of RP, age of onset, sex), clinical (digital topography of attacks, asymmetry of RP, functional severity, course during summer, circumstances of occurrence) and investigational data (digital plethysmographic cold test). No significant differences were found between apparently primary RP with signs of thoracic outlet and those without signs of thoracic outlet as concerns the parameters usually distinguishing Raynaud's syndrome from Raynaud's disease (family history of vasospasm, sex, asymmetry of RP, thumb involvement, digital vascular reactivity to cold). On the other hand, significant differences are noted for the following parameters: age of onset (p = 0.005), course during summer (p = 0.031), circumstances of occurrence (p = 0.0007), digital topography of attacks (p = 0.004), functional severity (p = 0.044), plethysmographic basal reactivity (p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Case-Control Studies↗
PubMed1995

Stapedectomy at the Singapore General Hospital--use of functional hearing analysis.

The results of stapedectomy surgery performed in Singapore General Hospital covering a period of over two years are reviewed. The diagnostic importance of selected clinical features and investigative procedures in otosclerosis is studied. The post-operative hearing status of twenty-six cases of primary stapedectomy is analysed using traditional audiometric and modern functional methods. Seventeen patients (65.4%) achieved closure of air-bone gap to less than 10 dB while the overall mean hearing gain was 28.6 dB. Using the Glasgow Plot parameter, 73.1% showed significant benefit from surgery, whilst the corresponding figure using the Belfast Rule of Thumb assessment technique was 57.7%. The validity of the foregoing evaluation techniques is compared. Different operative techniques, including variations in fenestra size and method of oval window seal showed statistically similar results. The scarcity of stapedectomy cases poses problems in the training of future specialists.

Acoustic Impedance Tests↗
PubMed1995

[The EDP systems for internal hospital cost accounting].

Computer systems for hospital cost accounting are in widespread use in foreign hospitals. In Norway, few hospitals have adopted such systems. Two products are currently being developed in Norway: KosPa (a system for calculating DRG costs) and Nirvana (a system intended for presentation of costs, rather than for overhead allocations and cost calculations). Both of these systems will have rather limited uses. If an organization needs a more comprehensive system with a wider selection of features, there are no Norwegian alternatives. It should be possible to implement a foreign system without too much trouble.

Accounting↗
PubMed1994

Correlations of cortical Hebbian reverberations: theory versus experiment.

Interpreting recent single-unit recordings of delay activities in delayed match-to-sample experiments in anterior ventral temporal (AVT) cortex of monkeys in terms of reverberation dynamics, we present a model neural network of quasi-realistic elements that reproduces the empirical results in great detail. Information about the contiguity of successive stimuli in the training sequence, representing the fact that training is done on a set of uncorrelated stimuli presented in a fixed temporal sequence, is embedded in the synaptic structure. The model reproduces quite accurately the correlations between delay activity distributions corresponding to stimulation with the uncorrelated stimuli used for training. It reproduces also the activity distributions of spike rates on sample cells as a function of the stimulating pattern. It is, in our view, the first time that a computational phenomenon, represented on the neurophysiological level, is reproduced in all its quantitative aspects. The model is then used to make predictions about further features of the physiology of such experiments. Those include further properties of the correlations, features of selective cells as discriminators of stimuli provoking different delay activity distributions, and activity distributions among the neurons in a delay activity produced by a given pattern. The model has predictive implications also for the dependence of the delay activities on different training protocols. Finally, we discuss the perspectives of the interplay between such models and neurophysiology as well as its limitations and possible extensions.

Action Potentials↗
PubMed1975

[Is coronarography justified in unstable angina? Experience of 130 cases].

The many important features of selective cine-coronary-arteriography to show the coronary arterial tree are demonstrated in the study of 130 such investigations carried out in patients with unstable angina. Cine-coronary-arteriography shows up the extent and location of obstructive atherosclerotic lesions. Ventriculography, together with measurement of ventricular pressures, gives information about the function and kinetic status of the left ventricle. These two investigations which do not, in our opinion, carry a greater risk in these cases than in cases with chronic angina, allow a precise diagnosis to be made. The early discovery of major lesions before infarction has occurred allow conclusions to be drawn about the prognosis and the appropriate treatment.

Angina Pectoris↗
PubMed1993

Plasma levels after oral methotrexate in children with juvenile rheumatoid arthritis.

Plasma levels of methotrexate (MTX) after oral administration of 6.4 to 11.2 mg/m2/week (mean 8.5 mg/m2/week) were studied in 33 children with severe juvenile rheumatoid arthritis (JRA). MTX concentrations were measured by a fluorescence polarization immunoassay (TDx) at 1, 2, 3, and 24 h after administration. The maximum level was observed in most patients after 1 h. No significant correlation was found between MTX dosage and the 1, 2, and 3-h plasma levels. No patient showed values in the range of probable toxicity 24 h after administration. A stepwise multiple regression analysis on 1, 2, and 3-h MTX levels, selected clinical features, dosage and duration of MTX therapy, and concomitant drug treatment showed that MTX concentrations at the different time points tend to be closely related; among the other variables, only concurrent treatment with salicylates was found to affect significantly the 3-h level. Serial determinations performed in 20 patients at the same oral dosage showed a wide interindividual and intraindividual variability of the plasma levels from the first dose to the next. Variable and unpredictable levels were observed also in most of the 8 patients studied after one or more increases of MTX dosage. No difference in MTX concentrations was observed between patients who responded to treatment and those who failed to respond, and between patients who had serum transaminase elevation and those who did not. Our results suggest that, until the pharmacokinetics of low dose MTX is clarified, routine therapeutic monitoring of MTX has a limited value in the clinical management of children with JRA.

Administration, Oral↗
PubMed1993

Interaction of neomycin with human erythrocytes.

This study has been undertaken to verify if neomycin, known to be toxic because it interacts with membrane-bound phosphatidylinositol-4,5-biphosphate, may lead to an extensive perturbation of the membrane organization of human erythrocytes. By comparison, the effects induced by a non toxic aminocyclitol antibacterial agent as spectinomycin were examined. Our data exclude extended alterations of the membrane and hence large structural changes of the whole cell for both the drugs probably as a consequence of the extreme difficulty of penetration because of their selective hydrophilic features. However, only neomycin seems to present a binding on negatively charged regions of erythrocyte membranes, that could be responsible of its remarkable toxicity.

Erythrocyte Membrane↗
PubMed1995

Single cell protein: a promising dietary substitute.

Promises and limitations in exploitation of microorganisms for single cell protein (SCP) production have been reviewed. Various aspects discussed include global protein problem, microbes as potential sources of food and feed with its advantages and disadvantages, salient features in selection of microorganisms for SCP production, production of SCP from petroleum based hydrocarbons, renewable raw materials like agricultural and forestry residues, industrial by-products and wastes, nutritional and safety evaluation of SCP, ways of improving SCP production, economics of SCP production and the present status of SCP in India.

Bacterial Proteins↗
PubMed1996

Image analysis for the evaluation of p53 expression in human cancers.

We compared the results of a subjective microscopic evaluation and an interactive image analysis of p53 expression in different human tumours. Expression of p53 was immunocytochemically detected by using the monoclonal antibody PAb 1801, and the evaluation was made blindly by two observers. Image analysis was performed on the same sections using DISCOVERY. The image was segmented into objects and background by interactive thresholding. Several morphological and densitometric features were selected in order to remove artefacts, lymphocytes, stromal cells and overlapping nuclei from the counting. The study was performed on series of 30 cases for different tumour types: breast, colon, oral cavity, ovary and lung cancer. Spearman's correlation coefficient ranged from 0.72 to 0.95 (P = 0.0001). Image analysis can therefore be considered as a quick and alternative approach to microscopic evaluation of nuclear immuno-determinations.

Antibodies, Monoclonal↗