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Biomedical subjects

Y Gong

Publications and source records attributed to Y Gong.

At least 181 records · Page 10Linked to original sources
PubMed1995

[Structural changes of extra pulmonary artery and pulmonary arterioles of rats during chronic hypoxia and their significance].

The structural changes of extra pulmonary artery (PA) and pulmonary arterioles and their effects on the pulmonary arterial pressure (PAP) under chronically hypobaric hypoxia (5000 m) were studied. The results showed that (1) The endothelial edema of extra PA and pulmonary arterioles gradually reduced and the endothelial proliferation took place along with the prolongation of hypoxic exposure followed by the recovery of endothelium-dependent relaxation evoked by Ach from depression. This result suggested that the release of E-DRFs from endothelium increased with the structural changes of endothelium in the course of hypoxic exposure, which may be a reason why PAP did not increase any more after 21 to 40 of days exposure. However, the strengthened contraction of PA, the proliferation of cells on the vascular wall, and the muscularity of pulmonary arterioles being related to the hypoxic endothelium may produce a negative effect on decrease of PAP, resulting in persistently higher PAP. (2) The structural changes of pulmonary arteriole endothelium were more severe than those of extra PA endothelium, indicating that pulmonary arterioles might be more sensitive to the stimulation of hypoxia.

Altitude Sickness↗
PubMed1995

The treatment of pain in bone metastasis of cancer with the analgesic decoction of cancer and the acupoint therapeutic apparatus.

The pain in 286 cases of bone metastasis of cancer was treated with an analgesic decoction of herbal drugs in combination with the Acupoint Therapeutic Apparatus that generated low frequency electric impulses into the acupoints. This series of patients comprised 104 cases of medium pain and 182 cases of severe pain, which was practically or completely relieved in 17 or 29 minutes respectively after the treatment; the total effective rate was 74.2% for 212 cases, and the duration of analgesic effect lasted 2.7 hours to 5.2 hours, averaging 3.6 hours. The cases that needed considerable dosages of analgesic tablets or sedatives markedly reduced their requests of such drugs. Determination of bone marrow stem cells indicated that the herbal treatment produced effects of promoting and protecting the stem cells. The rate of lymphocyte transformation was 45-76% before the treatment and rose to 57-96% after the treatment, demonstrating an increase of 15.2%, which was statistically significant (P < 0.001). The analgesic effect of the decoction was not correlated to the age and sex of the patients or the variety of cancer, except that it was not effective for uterine carcinoma. The main side effects included nausea, vomiting, somnolence, and numbness of the tongue.

Acupuncture Therapy↗
PubMed1994

Effect of selenite on tumor cell invasiveness.

Pre-exposure of HeLa or NIH:OVCAR-3 cells to selenite resulted in a dose-dependent decrease in the ability of the cells to invade a layer of Matrigel, a reconstituted basement membrane preparation. In contrast, selenate, selenomethionine and sulfite had no significant effect on cell invasiveness. Exposure of HeLa cells to selenite also resulted in a decrease in two of the necessary steps of the invasion process, attachment and mobility; in contrast, exposure of OVCAR cells decreased attachment but not mobility. There was an apparent correlation between the processes that are affected by selenite and those that involve the cellular fibronectin receptor (alpha 5 beta 1 integrin).

3T3 Cells↗
PubMed1994

Hormonal regulation of proliferation and transforming growth factors gene expression in human endometrial adenocarcinoma xenografts.

We have previously shown that estrogen and progestins regulate both cellular proliferation and transforming growth factor (TGF) expression in human endometrial adenocarcinoma cells in vitro. In the current study we examined the regulation of TGF-alpha and -beta 1 expression in endometrial adenocarcinoma xenografts. Four human endometrial adenocarcinoma cell lines were inoculated into female BALB/c nude mice. Administration of 17 beta-estradiol (E2) increased tumor size in intact mice inoculated with Ishikawa, HEC-50 and HEC-1B cells but inhibited growth of HEC-1A xenografts. 4-Hydroxy tamoxifen (OH-Tam) had similar effects to E2 in animals carrying Ishikawa and HEC-1A cell xenografts but had no significant effect on growth of HEC-50 or HEC-1B xenografts. In intact mice inoculated with OH-Tam pellets and Ishikawa cells, the tumors were larger and had lower levels of TGF-alpha mRNA than in untreated or E2 treated mice. In mice carrying Ishikawa, HEC-50 and HEC-1B cell xenografts none of the hormones or agents tested altered TGF-beta 1 mRNA levels. In contrast, both E2 and OH-Tam significantly increased xenografts TGF-beta 1 mRNA levels in HEC-1A xenografts as well as significantly reduced tumor size. Medroxyprogesterone acetate (MPA) had no effect on tumor size of Ishikawa, HEC-1A and HEC-1B cell cell xenografts but significantly increased the size of HEC-50 xenografts. MPA significantly reduced TGF-alpha expression in Ishikawa cell xenografts but had no effect in the other cell xenografts. MPA had no effect on TGF-beta 1 expression in any of the xenografts. These observations demonstrate a discordance between the hormonal effects on TGF expression and cellular proliferation and argue against a major role for the TGFs in regulation of human endometrial adenocarcinoma cell proliferation in vivo.

Adenocarcinoma↗
PubMed1994

Genetic study of indirect inguinal hernia.

We performed a genetic analysis of 280 families with congenital indirect inguinal hernia ascertained in Shandong province. The multifactorial threshold model and segregation analysis were applied to these families to investigate the mode of inheritance of congenital indirect inguinal hernia. Our results indicate that congenital indirect inguinal hernia is not compatible with a multifactorial threshold model, and the frequent vertical transmission and high segregation ratio suggest autosomal dominant inheritance with incomplete penetrance and sex influence. Through further pedigree analysis of the multiple case families with at least two closely related affected members, we noted preferential paternal transmission of the disease gene, which might suggest the role of genomic imprinting in the aetiology of this condition.

Chi-Square Distribution↗
PubMed1994

The kinetics of cytoplasmic granule secretion in natural killer cytotoxicity.

Antiserum against purified cytoplasmic granules from rat LGL tumor cells, and protein A-gold immunoelectron microscopy were used to study the secretory events in lysis of YAC-1 tumor cells by rat LGL tumor cells or by isolated LGL from normal rats. After 30 min incubation of effector and target cells together, gold-labeled cytoplasmic granules were often seen concentrated in the area of the LGL adjacent to the bound YAC-1 target. Within 60 min, the granules were observed to move to the cell border near the conjugated site. At this point, the granules were fused with the cell membrane, and subsequently released the gold-labeled contents into the junction between the LGL and the target cell. Gold particles could be seen at the E-T interface, on the LGL surface, or sometimes on the target cell surface. These data provide direct evidence for the hypothesis that under conditions of active cytotoxicity, natural killer cells secrete their cytoplasmic granule contents leading to the deposition of granule material on the target cell surface and the eventual lysis of the cell.

Animals↗
PubMed1994

[Study on genetic epidemiology of albinism].

Segregation analysis and consanguinity analysis were applied to 37 albinism families ascertained from Shandong province (P. R. China) to study the genetic heterogeneity of the disease. Our results show that albinism is an autosomal recessive disease with multilocus. The least number of the detrimental loci is 8, The average frequence of detrimental genes is 0.0023, and 3.83% individuals in general population are carriers. The incidence among the offsprings of the first cousin marriages would be 22 times higher than that in the general population.

Albinism↗
PubMed1994

The Yantai model of community care for rural psychiatric patients.

The main characteristics of the Yantai model are (a) a three-tier (county, township, village) management structure; (b) the vertical integration of community mental health workers, including a professional advisory group of psychiatrists from the central psychiatric hospital, groups of community psychiatrists at small county psychiatric hospitals, non-psychiatric physicians who run psychiatric out-patient clinics at township general hospitals, and village paramedics ('village doctors') who supervise patients in the community; (c) ongoing training of all community mental health workers; (d) registration and yearly follow-up of all patients with mental illnesses in the community; (e) provision of home-care services to a proportion of acutely ill patients; and (f) most of the cost of the service is borne by the state. The network of services provided by this model makes it convenient for patients to obtain treatment and, if necessary, go into hospital; it reduces the economic burden on the family and the community; it combines treatment, prevention, rehabilitation, and supervision under one administrative network; and it decreases the overall level of psychopathology and psychosocial dysfunction in the community.

Adolescent↗
PubMed1993

[Application of RFLP analysis to Duchenne and Becker muscular dystrophy in Shandong Province. I. Carrier detections in females at risk].

There were eight intragenic and two flanking bridge DNA polymorphic markers used in the RFLP analysis in 21 Duchenne and Becker muscular dystrophy selected from nine different districts in Shandong Province. A total number of 173 individuals of the families were accepted for gene tracking and carrier detection, as well as prenatal diagnosis. Based on the frequency of the probe polymorphism tested in our study of 53 unrelated individuals, one to three high polymorphic probes were sequentially used and all families presented the informativeness in RFLP analysis. Some more introgenio probes were supplied for assessment of mutated sites and carrier status with the help of gene phases, if recombinations were found. Our results presented a ratio of 85.45% of carrier detection at risk females with 95% or more reliability, including 17 carriers and 30 non-carriers. It was not able to ascertain the carrier status of 8 females because of DNA absence from key family members. Finally, we proposed a diagnostic procedure for the RFLP analysis to DMD/BMD families.

Female↗
PubMed1993

Enhanced expression of mRNA for transforming growth factor-beta, type I and type III procollagen in human post-burn hypertrophic scar tissues.

To explore the possible role of locally synthesized transforming growth factor beta-1 (TGF-beta 1) and procollagen gene expression in postburn hypertrophic scars, we have compared mRNA levels for type I and type III procollagen and TGF-beta 1 in human hypertrophic scar tissue with normal dermis obtained from the same patients as a control. Northern blot analysis of total RNA extracted from hypertrophic scar tissue and normal skin demonstrated two transcripts for the pro-alpha 1(I) chain (5.8 kb and 4.8 kb) and for the pro-alpha 1(III) chain (5.4 kb and 4.8 kb) and one transcript (4.9 kb) for TGF-beta 1. Quantitative analysis of dot blot autoradiograms of mRNA from three samples of hypertrophic scar tissue and normal skin showed average increases of 102% (p < 0.05) for pro-alpha 1(I), 91% (p < 0.06) for pro-alpha 1(III), and 61% (p < 0.05) for TGF-beta 1. Three additional hypertrophic scar samples were quantitatively analyzed on Northern blots and showed increases of 246%, 102%, and 250% of the specific messages for pro-alpha 1(I), pro-alpha 1(III), and TGF-beta 1 relative to a normal skin control. Two transcripts (4.9 kb and 2.5 kb) for TGF-beta 1 were identified in cultured fibroblasts. In contrast to the results from tissue, the level of these transcripts in fibroblasts cultured from hypertrophic scar tissue and normal skin were not significantly different, suggesting that the synthesis of this growth factor is stimulated in tissue by a presently unknown mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Differential effects of estrogen and antiestrogen on transforming growth factor gene expression in endometrial adenocarcinoma cells.

While antiestrogens are useful agents in the treatment of breast cancer, the usefulness of these agents in the treatment of endometrial cancer remains controversial. There is some concern that the currently available antiestrogens may have partial agonist activity in uterine tissue. To better understand the mechanisms by which estrogens and antiestrogens modulate growth of endometrial adenocarcinoma cells, we have compared the effects of 17-beta estradiol and three antiestrogens, 4-hydroxytamoxifen (OH-TAM), ICI 164384, and LY 117018 on proliferation and transforming growth factor (TGF) mRNA accumulation in two human endometrial adenocarcinoma cell lines. In HEC-50 cells, neither estradiol nor anti-estrogens had any effect on cell proliferation or TGF mRNA abundance under estrogen-depleted culture conditions [basal medium containing 1% twice charcoal-treated fetal bovine serum (ctFBS)] or in the presence of estrogen (basal medium containing 5% fetal bovine serum). At very high concentrations, both estradiol and OH-TAM caused a small decrease in HEC-50 cell proliferation in medium containing 5% serum. In contrast, the antiestrogens had different effects on Ishikawa cells, depending upon the culture conditions. In medium containing 5% fetal bovine serum, the antiestrogens inhibited cell proliferation and significantly decreased TGF-alpha mRNA abundance and TGF-alpha secretion. OH-TAM was more potent than the other antiestrogens. Under these culture conditions, estradiol had no effect on cell proliferation or TGF-alpha mRNA levels but increased TGF-alpha secretion. In medium supplemented with 1% ctFBS, estradiol increased cell proliferation and TGF-alpha mRNA (2.72-fold, P less than 0.005) and TGF-alpha secretion (700 +/- 156 versus 250 +/- 23 pg/10(6) cells/24 h, P less than 0.05), whereas OH-TAM, which also stimulated cell proliferation, reduced TGF-alpha mRNA abundance (P less than 0.05) but had no significant effect on TGF-alpha secretion. Under these conditions, ICI 164384 and LY 117018 had no effect on either cell proliferation or TGF-alpha expression. Estradiol treatment decreased, whereas OH-TAM increased, epidermal growth factor receptors in Ishikawa cells. Both estradiol and the antiestrogens decreased TGF-beta 1 mRNA abundance when cells were grown in media containing 1% ctFBS. In summary, the response of human endometrial adenocarcinoma cells to estrogen and antiestrogens varied between cell lines and was dependent upon the culture conditions used. In addition, OH-TAM, unlike the other two antiestrogens tested, had growth-stimulating effects on Ishikawa cells.

Adenocarcinoma↗
PubMed1992

Mechanisms of growth inhibition by antiestrogens and progestins in human breast and endometrial cancer cells.

Marked changes in both growth factor and proto-oncogene expression occur due to treatment of hormonally-responsive human cancers with progestins and antiestrogens. In human endometrial cancer cell lines the antiproliferative effects of progestins and antiestrogens in a particular cell line appear to be associated with similar effects on growth factor and/or proto-oncogene expression. This suggests that although these compounds initially interact with different steroid hormone receptors, the molecular mechanisms of their growth inhibition may be essentially similar. In the case of human breast cancer cell lines, however, the effects of progestins and antiestrogens on gene regulation are often different, suggesting that the molecular mechanisms of progestin and antiestrogen growth inhibition may be essentially dissimilar.

Breast Neoplasms↗
PubMed1992

Effects of transforming growth factors and regulation of their mRNA levels in two human endometrial adenocarcinoma cell lines.

The effects of the transforming growth factor-beta 1 (TGF-beta 1) and epidermal growth factor (EGF) on the growth of cells from 2 endometrial cancer lines, Ishikawa and HEC-50 were evaluated by measuring rates of DNA synthesis and changes in cell numbers during culture. EGF at 17 and 1.7 nM concentrations consistently enhanced HEC-50 cell proliferation. TGF-beta 1 inhibited Ishikawa cell proliferation but, unexpectedly for epithelium-derived cells, stimulated HEC-50 cell growth. This effect is of interest as it indicates that endometrial cells can acquire an altered responsiveness to a growth inhibitor during the process of malignant transformation. Northern blot analyses showed expression of TGF-alpha, TGF-beta 1 and EGF receptors mRNA in both cell lines. Neither estradiol (E2) nor 4-hydroxytamoxifen (OHTam) affected mRNA levels for either TGF-alpha or TGF-beta in HEC-50 cells, a line unresponsive to E2 for proliferation. In Ishikawa cells, previously shown to respond to both E2 and OHTam by increasing proliferation rates, E2 increased TGF-alpha mRNA and reduced TGF-beta mRNA levels. OHTam lowered the levels of both mRNA species, although the effect was greater on TGF-beta than TGF-alpha mRNA. These data are consistent with, but do not prove, the existence of a possible autocrine regulation by TGF-alpha and TGF-beta of human cancer cell proliferation, which might be under E2 influence in Ishikawa cells.

Adenocarcinoma↗