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Biomedical subjects

L M Wang

Publications and source records attributed to L M Wang.

141 records · Page 8Linked to original sources
PubMed1987

Comparative effects of diverse vertebrate gonadotropins on androgen formation in vitro from testes of roosters and mice.

A study was carried out to compare the androgen formation activity of gonadotropins from diverse vertebrate species by rooster and mouse testes in vitro. The dispersed testicular interstitial cells from 6- to 7-wk-old mice or testicular slices from 3- to 4-mo-old roosters were incubated with varying doses of luteinizing hormones (LHs)/gonadotropins (GTHs) in Medium 199 containing isobutyl-methyl-xanthine and N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid buffer (pH 7.4) at 34 degrees C (mice) or 37 degrees C (roosters) for 4 hr under continuous aeration of 95% O2-5% CO2 in a Dubnoff incubator shaken at 100 cycles/min. Androgen in the medium was measured by radioimmunoassay. The results revealed that dose-related androgen formations were obtained both in rooster and mouse systems in response to stimulations of all LHs/GTHs tested. The mouse system was more responsive to mammalian LHs and placental GTHs, less responsive to LHs from chickens, frogs, and turtles, and extremely unresponsive to piscine GTHs. In contrast, the rooster system was highly responsive to LHs from both mammals and chickens in androgen formation; it was also responsive to LHs from turtles and frogs as well as to piscine GTHs, although with relatively lower sensitivity. The rooster testis system is thus suitable for in vitro bioassay of LHs/GTHs from virtually all vertebrate classes, whereas the mouse testis system is more suitable for bioassay of mammalian LHs and placental GTHs. The differential androgen formation potencies of the diverse vertebrate GTHs in testis systems between roosters and mice indicate that a divergence exists in the testicular receptors between the two animal species.(ABSTRACT TRUNCATED AT 250 WORDS)

Androgens↗
PubMed1985

[Effect of sodium selenite on the antitumor function of spleen lymphocytes in mice].

Sodium selenite in drinking water (1 ppm) was given to normal and hepatoma-bearing mice for 14 days. Spleen lymphocytes were incubated with hepatoma cells and 3H-TdR incorporation was measured. Sodium selenite increased the ability of spleen cells to inhibit 3H-TdR incorporation into hepatoma cells by more than 40%. In the meantime, in the spleen lymphocytes of normal and hepatoma-bearing mice, the activities of ATPase, acid phosphatase and alkaline phosphatase were definitely higher than that of the control (ATPase increased by 35.5% and 65.0%; acid phosphatase increased by 113.0% and 93.0%; alkaline phosphatase by 64.7% and 69.0%, respectively). These results suggest that sodium selenite (1 ppm), like immunologic stimulator such as bacillus Calmette Guérin (BCG), be able to stimulate the immunologic function of organism against hepatoma.

Acid Phosphatase↗
PubMedDate not supplied

First-trimester prenatal diagnosis of severe alpha-thalassemia.

By means of chorion biopsy together with restriction endonuclease analysis of fetal DNA, first trimester diagnoses were successfully made in 33 fetuses at risk for Bart's hydrops fetalis. Seven pregnancies with Hb H or hydrops fetalis were therapeutically terminated before 4 1/2 months of gestation. Of the 26 pregnancies intended to continue, 18 have come to term with normal deliveries; one with threatened abortion was terminated at the end of the first trimester and, seven are progressing normally.

Biopsy↗
PubMedDate not supplied

Biochemical and cellular aspects of the anticancer activity of selenium.

Aberrant differentiation is a frequent hallmark of tumors, suggesting that modulators for differentiation and proliferation play a role in multistage carcinogenesis and that their use can also be exploited in cancer chemoprevention and therapy. We have demonstrated that selenium (Se) may be a modulator for the differentiation and proliferation of tumor cells. Evidence has been obtained that Se exerts the following effects: reversing changes of biochemical phenotypes toward normal levels, including reduction of cGMP level and cAMP-dependent protein kinase isozyme type I; increase in cAMP level and cAMP-dependent protein kinase isozyme type II, and altering membrane properties. Furthermore, we have obtained support for this hypothesis utilizing experiments on cultured human liver cell lines. It is demonstrated that Se can lead to the following changes: a. reduction of mitotic index; b. increase in the adhesiveness of cells; c. decrease in confluent saturation density and induction of an early contact inhibition; and d. decrease in tumorigenicity. For the purpose of comparison, the effects of Se on the normal counterparts was also studied. Contrary to what was observed above, there was no significant change in both biochemical and cellular aspects of normal cells treated analogously.

Animals↗
PubMedDate not supplied

The relationship between self-reported cocaine withdrawal symptoms and history of depression.

This study examined the relationship between cocaine withdrawal and lifetime history of depression (major depression, dysthymia). Participants with a history of regular cocaine use (n = 146) were administered the Structured Clinical Interview for the DSM-IV (SCID) and were asked to recall whether they experienced any of the six DSM-IV cocaine withdrawal symptoms. Results of bivariate analyses demonstrated that those meeting criteria for the cocaine withdrawal syndrome (dysphoria plus two or more other symptoms), in comparison to those who did not, were significantly (P<.001) more likely to have a lifetime history of depression. Lifetime history of depression was also more common in those individuals reporting the withdrawal symptoms of "dysphoria" (P<.001), "insomnia/hypersomnia" (P<.05), "vivid unpleasant dreams" (P<.01), and "psychomotor agitation/retardation" (P<.01). These relationships remained significant after controlling for demographics, severity of addiction, and the presence of opiate, alcohol and cannabis dependence or abuse. The withdrawal symptoms of "fatigue" and "increased appetite" were not associated with mood history. Results suggest that lifetime history of depression is strongly related to whether or not a cocaine abuser self-reports withdrawal symptoms. Several competing hypotheses regarding the nature of this relationship are discussed.

Adult↗
PubMedDate not supplied

Telehealth and communication technologies in health: summary and action plan.

INTRODUCTION: Rapid innovations and improvements in communication technologies have opened many new channels for health education and delivery, as well as disaster management. Theme 2 examined the role and applicability of these technologies to Disaster Medicine and Management and the various issues involved in their use. METHODS: Details of the methods used are provided in the introductory paper. The chairs moderated all presentations and produced a summary that was presented to an assembly of all of the delegates. The chairs then presided over a workshop that resulted in the generation of a set Action Plans that then were reported to the collective group of all delegates. RESULTS: Main points developed during the presentations and discussion included harnessing convergence, seeking interoperability, building partnerships and making it appropriate. This group identified four Principles of Action underlying its plan: (1) investigate possibilities, (2) identify stakeholders, (3) invite participation, and (4) involve discussants in activities. DISCUSSION: Action plans were categorized into three areas that included "thinking globally, acting regionally", forming a telehealth advisory group, and increasing corporate partnerships. CONCLUSIONS: Technology is opening many opportunities that have applications in disaster management. To optimize benefits, goals and standards must be agreed upon and implemented.

Cooperative Behavior↗