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Biomedical subjects

X Yao

Publications and source records attributed to X Yao.

176 records · Page 10Linked to original sources

Enhancement of thymic recovery after cyclosporine by recombinant human growth hormone and insulin-like growth factor I.

Correlation of thymic changes with the development of CsA-associated syngeneic graft-versus-host disease (sGVHD) suggested that the development of tolerance depends on the prompt regeneration of the thymus after stopping CsA. Accordingly, we have tested recombinant human growth hormone (rhGH) and recombinant human insulin-like growth factor I (rhIGF-1) to determine if they accelerate reconstitution of the rat thymus after CsA-induced involution. After 14 days of CsA, the thymus has marked medullary involution but normally recovers fully in 6 weeks. In this study, LEW rats were injected with vehicle, rhGH, or rhIGF-1 for 21 days after stopping CsA and were examined. The vehicle-treated rats showed partial recovery with respect to Hassall's corpuscles, class II antigen expression, medullary size, medullary dendritic cells (DC), and T cell maturation. The mature thymocytes were predominantly CD8+ T cells. Both rhGH and rhIGF-1 induced significant thymic enlargement compared with the vehicle-treated rats. They also both significantly enhanced regeneration with respect to Hassall's corpuscles. The mature thymocyte population had significantly greater CD4+ cells. In addition, rhIGF-1 induced a significant improvement in the medullary size and medullary DC. While the medullae of a normal thymus are in intimate contact with cortical class II antigen, after CsA the cortex adjacent to the medulla is primarily class II antigen negative. RhGH significantly increased the class II antigen in the deep cortex while rhIGF-1 demonstrated a trend toward greater expression in this region (P = 0.06). We conclude that rhGH and rhIGF-1 accelerate thymic regeneration post-CsA. Further studies are now indicated to establish the potential for these factors to enhance the development of antigen-specific tolerance.

Animals↗

[Relation between the levels of estrogen receptor and progesterone receptor and clinicopathological status in human endometrial carcinomas].

Estrogen receptor (ER) and progesterone receptor (PR) assays were performed by direct fluorescent histochemical methods in 20 endometrial carcinomas and 9 endometria of para-carcinomas. ER + and PR + were found in the patients who had not received chemotherapy and/or radiotherapies. In 4 adenosquamous carcinomas, the contents of ER and PR of adenocarcinoma components were higher than those of squamous carcinoma components. Blocking tests proved the specificity of ER and PR for estradiol and progesterone respectively. The levels of ER and PR in endometria of para-carcinomas were higher than those in carcinomas. There were higher levels of ER and PR in early clinical stage than in advanced stage, in cases free from cervical involvement than in cases cervical involvement, and in well differentiated carcinomas than in poorly differentiated carcinomas. ER and PR contents did not correlate with the depth of myometrial invasion or menopausal status. In the patient group followed up for half a year or more, 4 patients with high-level ER and PR had a good response to 17 alpha-progesterone caprate. The patients with ER + and PR + had a longer survival period than those with ER- and PR-. Our results indicated that the assay of ER and PR might be valuable for predicting the response to endocrine therapy and prognosis for patients with endometrial carcinoma.

Adenocarcinoma↗

A New Minor Saponin from the Leaves of Panax ginseng.

Seventeen compounds were isolated from the leaves of PANAX GINSENG C. A. Meyer. Among them, a new minor saponin was established as 3beta,6alpha,12beta-trihydroxy-dammar-20(22), 24-diene-6- O-alpha- L-rhamno-pyranosyl-(1-->2)-beta- D-glucopyranoside ( 2). Fourteen compounds were identified as 20( R)-protopanaxadiol ( 1), 20( R)-protopanaxatriol, ginsenoside-Rh (3), 20( R)-ginsenoside-Rh (2), 20( S)-ginsenoside-Rh (2), ginsenoside-Rh (1), -Rg (3), -Rg (2), -Rg (1), -Re, -Rd, -Rc, -Rb (2), -Rb (1); the others are still under investigation.

Journal Article↗

[Antiarrhythmic effect of Oenanthe javanica (Bl.) DC. injection].

The antiarrhythmic effect of Shuiqin (Oenanthe javanica) injection was studied in rats. An injection of 3 ml/kg iv could significantly antagonize the arrhythmias induced by aconitine and BaCl2, and decrease the rates of ventricular fibrillation and death induced by CaCl2. The results suggest that Shuqin injection has a significant antiarrhythmic effect on experimental rats.

Aconitine↗

Acid secretion in alpha-toxin-permeabilized gastric glands.

Rabbit gastric glands were treated with alpha-toxin to test for permeabilization of basolateral membrane and retention of functional activity of parietal cells. Treatment with up to 400 U alpha-toxin/mL resulted in a dose-dependent increase in permeabilization, as judged by nuclear uptake of trypan blue (960 daltons), while causing relatively little loss of cytoplasmic macromolecules in the size range of lactate dehydrogenase (134,000 daltons). In the presence of cAMP and ATP, alpha-toxin-permeabilized resting gastric glands were stimulated to accumulate aminopyrine by approximately 10-fold over glands incubated without added nucleotides. Aminopyrine accumulation in stimulated permeabilized glands was inhibited by specific H+,K(+)-ATPase inhibitors, omeprazole and SCH-28080, and by the selective inhibitor of protein kinase A, H-89 (IC50 = 7.17 +/- 2.05 microM; n = 4). Aminopyrine accumulation in the alpha-toxin-treated glands was dependent on both exogenous ATP and cAMP; however, when no exogenous ATP was present, cAMP-activated aminopyrine accumulation reached approximately 50% of maximum, and at levels of ATP > 0.05 mM, maximal aminopyrine accumulation occurred without exogenous cAMP. In the presence of ATP alone, aminopyrine accumulation in permeabilized glands achieved 61.1 +/- 3.2% (n = 10; range, 50-70%) of the values measured on paired samples of intact glands stimulated with histamine plus isobutylmethylxanthine. These results demonstrate the functional responsiveness of alpha-toxin-permeabilized resting gastric glands. The participation of a protein kinase A dependent pathway during activation of permeabilized parietal cell is proposed.

1-Methyl-3-isobutylxanthine↗

Regression and clonally distinct recurrence of human immunodeficiency virus related Burkitt-like lymphoma during antiretroviral therapy.

An increased incidence of intermediate to high-grade Non Hodgkin's Lymphoma is found in individuals with AIDS. Although immune function in AIDS patients can be improved through the use of antiretroviral therapy, the contribution of these drugs to lymphoma regression is not known. Here we describe the complete regression and subsequent recurrence of high grade, Burkitt-like lymphoma during antiretroviral therapy in a patient with AIDS. Antiretroviral therapy resulted in diminished viral load and modest improvement in CD4+ T cell counts. Lymphoma regressed initially, but relapsed 3 months later. Tissue taken from the initial and recurrent tumor demonstrated different clonal rearrangements. The recurrent lymphoma did not respond to continued antiretroviral therapy. In Conclusion, antiretroviral therapy may contribute to lymphoma regression in AIDS lymphoma. Clinically recurrent disease may be clonally distinct.

Adult↗