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C S Tang

Publications and source records attributed to C S Tang.

At least 91 records · Page 5Linked to original sources
PubMed1997

[Distribution of obese protein in the mouse tissue].

In the present study, the contents of obese protein of tissue from liver, brain, abdominal wall fat, skeletal muscle and the contents of plasma OP of mice were measured with radio immunoassay. The results showed that the contents of OP were much higher in the brain than that in the abdominal wall fat tissue (P < 0.01). The liver and the skeletal muscle tissue did not show the presence of OP. The contents of OP of abdominal wall fat tissue were lower in the female than that in the male mice (P < 0.05).

Abdominal Muscles↗
PubMed1997

[Effect of anoxic preconditioning on protein kinase C activity in neonatal rat cardiomyocytes].

In a model of anoxia/reoxygenation (A/R) of cultured rat cardiomyocytes, protection of cellular damage, activation of protein kinase C (PKC) and PKC-mediated protein phosphorylation by anoxic preconditioning (APC) can be demonstrated as shown by the increase of cell viability, attenuation of formation of lipid peroxides (MDA) and lowering of the leakage of lactate dehydrogenase (LDH) and protein from cells. The results also show that transient anoxia mimicked the outcomes of activation of PKC as shown by increased incorporation of 32P, especially in the 66 kD and 31 kD protein fractions. Preincubation of cardiomyocytes with H7 (an inhibitor of PKC) completely abolished these protective effects of transient anoxia. Protein phosphatase inhibitor OA mimicked the protective effects of A/R, while protein phosphatase activator BDM induced a complete abolishment. In short, we conclude that the protective effect of APC is medicated by activation of PKC.

Animals↗
PubMed1997

[Effects of basic fibroblast growth factor on anoxia/reoxygenation injury of rat neonatal cardiomyocytes].

The effects of basic fibroblast growth factor (bFGF) on anoxia/reoxygenation (A/R) injury and protein kinase C (PKC) activity were studied on a model of A/R injury of neonatal rat cardiomyocytes to investigate the possibility of its using as a substrate for pharmacological preconditioning. The data indicated that bFGF improved the viability of cardiomyocytes, lowered the deplection of ATP and leakage of intracellular lactate dehydrogenase (LDH) in a concentration-dependent manner. PKC inhibitor, H7, completely abolished the protective effects. It was also found that bFGF directely activated PKC in cardiomyocytes in a time course similar to that in hypoxic preconditioning. The data suggested that the protective effect of bFGF on cardiomyocyte A/R injury might be mediated by PKC.

Animals↗
PubMed1997

[Effects of hypoxia/reoxygenation on mitogen-activated protein kinase activity in cultured neonatal rabbit cardiac myocytes].

Cardiomyocytes subjected to brief episode of hypoxia possess a resistance to serious damaging effect exerted by a subsequent long-time hypoxia on these cells, which is called hypoxic preconditioning (PC). The pathway of intracellular signal transduction during hypoxia PC has not yet been validated. On a model of hypoxia/reoxygenation (H/R) of cultured neonatal rabbit cardiomyocytes, the present study is taken to investigate the changes of mitogen-activated protein kinase (MAPK) and ribosomal S6 kinase (S6K) activity. It was found that intracellular total MAPK and nuclear MAPK, after a 15-min period of reoxygenation preceded by a single 60-min period of hypoxia, were increased by 95% and 230%, respectively. Intracellular S6K activity increased by 142% at 30 min of H/R vs the control group (P < 0.01). Phosphatase 1 (PPase 1) inhibitor (ocadaic acid, OA 1 mumol/L) augmented the increase of MAPK and S6K activity induced by H/R. However, tyrosine kinase (Tyr K) inhibitor (genistein), protein kinase C (PKC) inhibitor (H7) and preincubation of cardiomyocytes with PKC activator PMA all reduced MAPK activation by H/R. Protein kinase A (PKA) inhibitor (H89), Ca2+/Calmodulin-dependent protein kinase (PKM) inhibitor (W7) or PPase 2a inhibitor (OA 10 nmol/L) had no significant effect on MAPK and S6K activity. The above results suggested that activation of MAPK and S6K activity during hypoxia/reoxygenation there might require participation of PKC, Tyr K and PPase 1, while PKA, PKM and PPase 2a were not involved.

Animals↗
PubMed1996

Factor structure of the Chinese version of the WAIS-R for Chinese adults in the lowest percentiles of IQ.

The Chinese version of the WAIS-R was factor analyzed for a sample of 130 Chinese adults in Hong Kong who had low intellectual abilities. All subtests except the Vocabulary subtest were included for analyses. Results supported a three-factor solution composed of Verbal Comprehension, Perceptual Organization, and Memory/Freedom from Distractibility Factors, as well as a two-factor solution of classic Verbal-Perceptual dichotomy. Comparison of present two- and three-factor structure with individuals having low or normal IQ in Mainland China and North America revealed satisfactory congruence coefficients. However, our general factor accounted for only a small portion of common and total variance (28.5% and 35.3% respectively). Error variances of our subtests were large when compared to normative samples of Mainland China and US. Results were discussed in terms of clinical interpretation of the WAIS-R subtests, danger of using short-forms to assess IQ and need for normative studies of WAIS-R in Chinese-speaking countries.

Adolescent↗
PubMed1996

Spontaneous N,N'-dibutylurea (DBU) formation in Benlate DF formulation under elevated temperatures.

Thermal degradation of benomyl in the fungicide Benlate DF at temperatures higher than 55 degrees C leads to the formation of N,N' -dibutylurea (DBU). External moisture is not required, since starch, an "inert" ingredient in the formulation, serves as a source of water. Enhanced phytotoxicity of the heat-treated, DBU-rich Benlate DF was demonstrated by lettuce seedling bioassay. Temperatures higher than 70 degrees C were recorded in a metal shipping container in June 1995 in Hawaii. Accumulation of DBU was observed in Benlate DF sealed in ampules and stored in this container. It is concluded that DBU formation is an intrinsic characteristic of Benlate DF at the temperatures tested. High temperature and high humidity in tropical regions provide ideal conditions for DBU formation in Benlate DF.

Benomyl↗
PubMed1996

Sexual harassment of Chinese college students.

Sexual harassment of Chinese college students with a focus on their awareness, experiences, responses, and expectations of institutional intervention to the problem was examined. 358 male and 491 female Chinese college students in Hong Kong participated. There were no gender differences in students' awareness of the phenomenon. Students' own experiences were less frequent than what they had heard about sexual harassment. Peer harassment occurred twice as frequently as faculty harassment. Compared to men, twice as many women said they had been sexually harassed. About one in four women students experienced various forms of sexual harassment and 1% were coerced into sexual activities during their college years by either teachers or peers. Students typically avoided and ignored the harassers and felt that the university should take up active roles in combating the problem. Comparisons with U.S. studies suggested that Chinese college students had a lower awareness and experience level in sexual harassment than U.S. students.

Adult↗
PubMed1996

Sodium nonivamide acetate: a non-pungently antinociceptive capsaicin derivative with unusual anti-inflammatory properties.

1. Bradykinin-induced vascular pain in conscious rats, hyperalgesia in the rat hind paw, rat hind paw edema induced by compound 48/80 and carrageenin and dye exudation induced by intraperitoneal injection of 0.7% acetic acid in mice were all inhibited by sodium nonivamide acetate (SNA). 2. Collagen and arachidonic acid-induced rabbit platelet aggregations were inhibited by SNA and capsaicin. In human platelet microsomes, prostaglandin E2 formation in arachidonic acid metabolite was not inhibited by SNA but was inhibited by capsaicin and indomethacin; thromboxane B2 formation and its synthetase activity were inhibited by SNA and capsaicin. 3. In the extracellular recording, SNA could not decrease the action potential amplitude of the vagus nerve. 4. The motor activity of mice induced by caffeine (1.0 mg/kg) was inhibited by SNA and capsaicin.

Animals↗
PubMed1996

Child abuse in Hong Kong revisited after 15 years: characteristics of victims and abusers.

The purpose of this paper was to examine the characteristics of the victims and abusers of child abuse cases on the Child Protection Registry in Hong Kong as of March 1995 and to compare findings with a similar community report of child abuse in Hong Kong conducted approximately 15 years earlier. As of March 31, 1995, there were 457 active cases of child abuse or suspected child abuse (44% male and 56% female) on the computerized Child Protection Registry. Fifty percent of the victims were grade school age children between 7-12, and 62.4% suffered physical abuse. The abusers or suspected abusers were 52% male and 48% female with nearly half (49%) in their thirties. The majority of abusers were married/cohabiting (75%) with only a grade school education (60%). As compared to 1979, there was an increase of sexual child abuse cases, female victims of child abuse, and an increase in male abusers or suspected abusers.

Adult↗
PubMed1996

The Chinese Gender Role Stress scales. Factor structure and predictive validity.

The present study aimed at examining the factor structure and predictive validity of the translated Masculine Gender Role Stress (MGRS) and Feminine Gender Role Stress (FGRS) scales in samples of Chinese college students and professionals (N = 482). Consistent with previous research, our results supported the theoretical assumption that stressors associated with gender role behaviors were sex-specific, and Chinese men generally scored higher on the MGRS factors but lower on the FGRS factors than Chinese women. Compared to professionals, students had higher scores on both Gender Role Stress (GRS) scales. The MGRS factors predicted somatic complaint and anxiety, whereas the FGRS factors predicted social dysfunction. Results of confirmatory factor analyses rejected a five-factor structure for the two Chinese GRS scales. Based on exploratory factor analyses, a more parsimonious three-factor solution was identified for each GRS scale. The revised three-factor GRS scales compared favorably with the original five-factor GRS scales in internal consistency, interfactor correlations, and prediction of psychological distress. The major discrepancy between the original and revised factor structure was related to the prediction of depressogenic symptoms. In sum, our suggested that the two GRS constructs were useful in the Chinese context, and the revised three-factor structure provided a viable alternative to the original five-factor structure.

Adolescent↗
PubMed1996

Marijuana and heroin use in Hong Kong Adolescents.

Data on marijuana and heroin use were obtained from 969 nonrandomized adolescent boys and girls in Hong Kong. Drug use prevalence rates were very high which was due to the fact that a large part of the sample was institutionalized offenders. All but two of the heroin users were incarcerated. Drug use frequencies were highly associated with psychosocial variables such as peer drug use, family drug use, susceptibility to peer pressure, perceived control to gain access to drugs, and perceived adverse consequences of drug use.

Adolescent↗
PubMed1996

[Changes in the calcium channels in rat cardiac cells during sepsis].

Changes in the number of calcium channels in two subcellular fractions, the sarcolemma and the light vesicle, of rat cardic cells were studied during sepsis. Sepsis was induced by cecal ligation and puncture (CLP). The results showed that some of the calcium channels in the light vesicle translocated to the sarcolemma during the early sepsis (9 h after CLP) while during the late sepsis (18 h after CLP), some of these in the sarcolemma translocated to the light vesicle. The mechanisms of redistribution of the calcium channels in the sarcolemma and the light vesicle during sepsis was not associated to the phosphorylation of the calcium channels by cAMP dependent protein kinase (PKA), Ca2+/calmodulin dependent protein kinase (PKM) and protein kinase C (PKC). Since beta-adrenergic receptors, muscarinic cholinergic receptors and Na+/K(+)-ATPase were also redistributed during sepsis, it is suggested that the redistribution might be non-specific.

Animals↗
PubMed1996

[Impairment in the phosphorylation of Ca(2+)-transport ATPase of rat liver endoplasmic reticulum during sepsis].

The phosphorylation of Ca(2+)-transport ATPase of rat liver endoplasmic reticulum (ER) during early and late septic shock induced by cecum ligation and puncture (CLP) was investigated by determining incorporation of [gamma-32P] ATP into Ca(2+)-ATP phosphoprotein intermediate. Hepatic endoplasmic reticulum was isolated by differential centrifugation with sucrose density gradient. The Ca(2+)-ATPase phosphoprotein intermediate was identified by SDS-PAGE. The results showed that the phosphorylation of Ca(2+)-ATPase (115 kD) was decreased respectively by 15-23% (P < 0.05) and 17-27% (P < 0.05) at 9 h (early sepsis) and 18 h (late sepsis), following the CLP in the rough, intermediate and smooth ER preparations. Kinetic analysis using rough ER showed that the Vmax for Ca2+ and for ATP for the phosphorylation of Ca(2+)-ATPase were decreased dramatically during early and late sepsis, but without changes in the K(m) values. These results demonstrate that the phosphorylation of the phosphoprotein intermediate of Ca(2+)-ATPase in rat liver was impaired during different phases of sepsis.

Animals↗
PubMed1996

[Endothelin-stimulated proliferation of thoracic artery smooth muscle cells involves activation of mitogen-activated protein kinase].

Endothelin (ET) is a potent vasoconstrictor whose responses are mediated through a common G-protein coupled receptor. So far little is known concerning its potential mitogenic capacity. In the present study, experiments were conducted to determine the role of mitogen-activated protein kinase (MAPK) activation in the rabbit thoracic artery smooth muscle cells (VSMC) in response to stimulation by ET-1. It was found that ET-1 produced concentration- and time-dependent increases in 3H-TdR incorporation and in MAPK activity of these cells. All the increases were inhibited by protein kinase C (PKC) inhibitors, such as Staurosporine (STP) and H-7 and by ETA receptor antagonist BQ123, but not by specific tyrosine kinase inhibitor Herbimycin A (Herb). Pre-treatment with PKC activator PMA (phorbol myristate acetate) for 24 h (PKC downregulation) significantly attenuated ET-1-induced MAPK activation. These results indicate that: (1) ET-1-stimulated proliferation of VSMC involves the activation of MAPK and (2) ET-1-induced MAPK activation is mediated through ETA receptor and PKC.

Animals↗
PubMed1995

Sexual aggression and victimization in dating relationships among Chinese college students.

Sexual victimization in dating relationships among female Chinese college students in Hong Kong was studied. Findings were compared to Chinese males' self-reports of sexual aggression. Nonstranger sexual victimization was common among Chinese female college students, especially for less intimate forms of sexual contact. Prevalence of sexual victimization was similar to that in North America for less intimate forms of contact but less prevalent for more intimate contact, including rape. A greater proportion of women than men reported the experience of several behaviors engaged in against a woman's will. These included kissing, and touching a woman's hand, knee, leg, or crotch.

Adult↗