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Biomedical subjects

A Weiss

Publications and source records attributed to A Weiss.

At least 379 records · Page 21Linked to original sources
PubMed1982

Studies on hormonal regulation of the growth of the craniofacial skeleton: II. Effects of a glucocorticoid hormone on sulfate incorporation by neonatal condylar cartilage.

Condylar cartilage of neonatal mice served as an experimental model to study the early in vivo effects of a single dose of a fluorinated synthetic analogue of cortisol on sulfate incorporation and matrix metachromasia. Twenty-four hours after the administration of triamcinolone hexacetonide condyles incorporated significantly less 35SO4, a feature that followed a dose-response relationship. Dexamethasone, another fluorinated synthetic analogue of cortisol, evoked a similar effect, as did triamcinolone. On the other hand, corticosterone, the natural glucocorticoid in rodents, induced a markedly milder effect, whereas hydrocortisone lacked it altogether. Progesterone, a nonglucocorticoid steroid hormone, induced a reverse effect as it was found to increase 35SO4 incorporation into condylar cartilage. The hormonal inhibitory effect upon 35SO4 incorporation persisted, for the most part, for 2 days, and thereafter the sulfation process appeared to have returned to normal values. Of interest was the finding that the latter response was not accompanied by distinct changes in the degree of matrix metachromasia when measured at the chrondroblastic zone. It, therefore, seems possible, though not as yet proved, that concomitant with the transient inhibitory effects on 35SO4 incorporation, the hormone also induced changes in the degradative processes within the cartilage matrix.

Animals↗
PubMed1981

[Hodgkin's disease. Results of diagnosis and therapy (author's transl)].

The principles of modern diagnosis and therapy of lymphogranulomatosis are largely standardized today. Whereas the 50% probability survival rate in a group of patients diagnosed before 1970 was about 2 years, 23 out of 30 with standardized diagnosis and therapy have survived until now. Full remission was obtained in 21 of 30 patients. In spite of these encouraging results, the synopsis of the course of the disease shows that relapses and complications must be reckoned with in lymphogranulomatosis. Side effects of therapy may also acquire considerable clinical importance in the individual case.

Adolescent↗
PubMed1981

[Cardiovascular risk factors in headquarters staff of the World Health Organization].

Analysis of 2333 medical files of the World Health Organization's headquarters staff in Geneva gives insight into the epidemiology of cardiovascular risk factors in nationals originating from 67 different countries but living in the same environment. The study confirms well established facts such as the prevalence of hypertension (HT) with respect to sex, age, and period of observation, its consequences and interrelation with high cholesterol levels, diabetes, and obesity. The importance of a medical service with emphasis on prevention is stressed. Major differences in relation to geographic origin are noted for men. The highest percentage of HT (32%) is noted for staff members from Germanic countries. There is a concentric decrease according to nationality: 29 to 25% for the other countries of Central, Western, and Southern Europe, 23 to 18% for the USSR, Arab countries and North America, 9 to 6% for South East and Eastern Asia and African countries south of the Sahara (p less than 0.05 between the extremes). India and Australia do not fit the pattern of concentric decrease, since a high percentage of men in those countries have HT. As the number of files available was insufficient to carry out the same analysis for women or to determine other factors of cardiovascular risk, the study will be extended to cover the staff of other International Organizations in Geneva.

Age Factors↗
PubMed1981

A superfusion method for the study of secretion activity of isolated cerebral and endocrine tissues.

This paper describes a new kind of superfusion technique that allows for the maintenance of small fragments of nervous tissue, such as of the hypothalamus and the pituitary and pineal glands, suspended in a very small perfusion chamber with a continuous flow of medium that reproduces "in vivo" conditions. Easy reproducibility; continuous flow of medium, which avoids short feedback phenomena; controlled conditions that are very close to those "in vivo" and the possibility of sequential treatments for the study of the dynamics of hormone release are some of the advantages of this method.

Animals↗
PubMed1981

Liver growth retardation in corticosteroid-treated neonatal mice.

This study examined the influence of triamcinolone hexacetonide on the growth and nucleic acid synthesis in the liver of neonatal mice. Following a single dose of the hormone the synthesis of DNA was significantly depressed, a feature that lasted for 72 hours. Thereafter an almost full recovery took place and by 144 hours no significant differences existed between hormone-treated livers and their nontreated controls. The above inhibitory effect was dose-dependent and was specific to steroids with glucocorticoid activity. A markedly different response was noted in regard to RNA synthesis. Hormone-treated livers revealed an initial increase in the uptake of 3H-uridine and RNa synthesis but later on revealed a significant decrease in the incorporation of uridine resulting in a marked reduction in the tissue's content of RNA. Concomitantly, the hormone increased significantly the protein content of the liver. It thus became clear that glucocorticoid hormones possess both a significant inhibitory effect upon the proliferative activity of neonatal hepatocytes and interfere with the latters' protein synthetic machinery, thereby affecting the normal growth of the liver at its critical period of growth and development.

Animals↗
PubMed1981

Inhibition of cytolytic T lymphocyte clones reactive with Moloney leukemia virus-associated antigens by monoclonal antibodies: a direct approach to the study of H-2 restriction.

H-2 restriction in cytolytic T lymphocyte (CTL)-mediated lysis of syngeneic murine Moloney leukemia virus (MoLV)-induced tumor cells was studied at the clonal level by testing the inhibitory effect of monoclonal anti-H-2 antibodies on the lytic interaction between CTL clones and target cells. Large numbers of MoLV-specific CTL clones were generated by placing limiting numbers of C57BL/6 regressor (responder) spleen cells into micro-mixed leukocyte-tumor cell cultures. The clonal CTL populations thus obtained were split into 5 aliquots and tested for lytic activity in the presence (or absence) of 1 of 3 monoclonal antibodies or of an anti-whole H-2b haplotype antiserum. Two of the monoclonal antibodies were directed against H-2Db and one against H-2Kb determinants. Specificity of these reagents had been verified by demonstrating inhibition of lysis by CTL populations directed against H-2Db and H-2Kb alloantigens. In 44 of a total of 51 clones tested, results showed selective inhibition by the anti-H-2Db (and the anti-whole haplotype) reagents, and lack of inhibition by the anti-H-2Kb antibody., Of the remaining 7 clones, none was inhibited by the anti-H-2Db antibody, and 3 were inhibited by the anti-whole haplotype antiserum. These studies show that the recognition of MoLV-associated antigens by the majority of CTL clones was restricted to the H-2Db region, and that there exists limited heterogeneity in the H-2 restriction of such clones.

Animals↗
PubMed1981

Retardative effects of a corticosteroid hormone upon chondrocyte growth in the mandibular condyle of neonatal mice.

This study examined the influence of triamcinolone hexacetonide, a long-acting synthetic analog of cortisol on the proliferative activity and subsequent development of chondroprogenitor cells in condylar cartilage of neonatal mice. It became evident that a single injection of relatively low doses of the hormone significantly reduced the uptake and incorporation of [3H]thymidine followed by a significant decrease in the number of young cartilage cells. A unique feature was the fact that at the same time condyles of triamcinolone-treated mice revealed an increase in the number of mesenchyme-like cells within the condylar chondroprogenitor zone. High values of correlation were noted between the inhibitory effects of the hormone upon the incorporation of [3H]thymidine, the number of mitotic figures (within the chondroprogenitor zone), and the dimension of the chondroblastic zone. This study indicates that in young animals fluorinated corticosteroid hormones possess a significant bivalent inhibitory effect upon both the proliferative activity of chondroprogenitor cells as well as upon capacity of the latter cells to differentiate into chondroblasts. In so doing, corticosteroids adversely affect the normal process of endochondral bone formation in one of the prominent growth centers within the craniofacial skeleton. Thus, in the developing animal, corticosteroids impair the growing mandible from expressing its inherent morphogenetic pattern.

Adrenal Cortex Hormones↗
PubMed1980

[Thoracic sonography with the rapid B picture (author's transl)].

The orienting investigation should be a compulsory component of every internist echographic status with the rapid B picture. Besides its diagnostic aspects, thoracic echography with the rapid B picture in the region of the pericardium is also of therapeutic importance for the reliable specific ultrasonic pericardial puncture for the relief a tamponading pericardial effusion. All radiological shadows which are not completely clear must be subjected to echographic assessment before proceeding to more expensive diagnostic measures. This permits the sonographic differentiation between a collection of fluid and a solid structure as far as the shadows are confined to the wall.

Adult↗
PubMed1980

Antigenic specificity of the cytolytic T lymphocyte response to murine sarcoma virus-induced tumors. III. Characterization of cytolytic T lymphocyte clones specific for Moloney leukemia virus-associated cell surface antigens.

Cytolytic T lymphocyte (CTL) clones specific for Moloney leukemia virus (MoLV)-derived tumor cells were generated by placing limiting numbers of C57BL/6 responder cells into mixed leukocyte-tumor cell microcultures. Under appropriate conditions (presence of stimulating tumor cells, accessory cells, and T cell growth factor), such cloned CTL could readily be expanded to provide large numbers of homogeneous, highly cytolytic CTL populations for further characterization. Using four target-cell types, three specificity patterns were observed: one reactive with the syngeneic MoLV-derived tumor only, one cross-reactive with an allogeneic MoLV-derived tumor, and one cross-reactive with normal allogeneic cells. Subclones derived from these three types of clones exhibited a high degree of stability in terms of lytic activity and specificity over a 4-mo period of observation. Three clones analyzed by flow cytofluorometry using monoclonal antibodies were all found to be of the Lyt-1+2+ phenotype. Furthermore, lysis of target cells by all of six clones tested was inhibited by anti-H-2Db (but not by anti-H-2Kb) monoclonal antibodies, demonstrating H-2Db-restriction at the clonal level.

Animals↗
PubMed1980

[Leading symptom: esophageal varices hemorrhage in a young man].

Indicating sign: Esophageal hemorrhages in adolescence. Congenital hepatic fibrosis and infantile polycystic disease of the kidneys. A 17-year-old patient with hypersplenism and signs of portal hypertension came to clinical treatment after an esophageal hemorrhage. Rare syndrome of congenital hepatic fibrosis with portal hypertension and splenomegaly, with infantile polycystic disease of the kidneys and aneurysms of the splenic artery was recognizable by means of ultrasound, laparoscopy and angiography. Therapeutically splenorenal shunt and splenectomy were carried out.

Adolescent↗
PubMed1980

Chromium in biological systems, I. Some observations on glucose tolerance factor in yeast.

Glucose tolerance factor (GTF) has been isolated from a commercially available yeast extract powder, by a simple procedure under mild conditions. This cationic yellow material enhances considerably CO2 production in several yeast strains, after a lag time which can be eliminated by preincubation with glucose. The enhancement of CO2 production by GTF is not specific for glucose, and its effect on galactose raises the possibility that it influences the transport of the sugar to the cells. The ineffectiveness of GTF on cell free extract and the results of a Michaelis plot for CO2 production support this hypothesis.

Biological Transport↗
PubMed1980

A new method of perineal reconstruction following vulvectomy.

We propose a method in which vulvar reconstruction could be accomplished at the time of vluvectomy. A full-thickness pedicle flap is rotated from the vaginal vault to the area of excision, providing excellent coverage without subsequent contracture, and obviating the need for clitorectomy. This technique may also aid in palliating the psychological trauma induced by genital disfigurement.

Adult↗