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Biomedical subjects

Li Su

Publications and source records attributed to Li Su.

At least 55 records · Page 3Linked to original sources
PubMed2004

Excision repair cross-complementation group 1 polymorphism predicts overall survival in advanced non-small cell lung cancer patients treated with platinum-based chemotherapy.

DNA repair is a critical mechanism of resistance to platinum-based chemotherapy. Excision repair cross-complementation group 1 (ERCC1) is the lead enzyme in the nucleotide excision repair process. Increased ERCC1 mRNA levels are related directly to platinum resistance in various cancers. We examined the association between two polymorphisms of ERCC1, codon 118 C/T and C8092A, which are associated with altered ERCC1 mRNA levels and mRNA stability, and overall survival (OS) in 128 advanced non-small cell lung cancer patients treated with platinum-based chemotherapy. The two polymorphisms were in linkage disequilibrium. There was a statistically significant association between the C8092A polymorphism and OS (P = 0.006, by log-rank test), with median survival times of 22.3 (C/C) and 13.4 (C/A or A/A) months, respectively, suggesting that any copies of the A allele were associated with poor outcome. No statistically significant association was found for the codon 118 polymorphism and OS (P = 0.41, by log-rank test), with median survival times of 19.9 (T/T), 16.1 (C/T), and 13.3 (C/C) months, respectively. In conclusion, the ERCC1 C8092A polymorphism may be a useful predictor of OS in advanced non-small cell lung cancer patients treated with platinum-based chemotherapy.

Adult↗
PubMed2004

XPD and XRCC1 genetic polymorphisms are prognostic factors in advanced non-small-cell lung cancer patients treated with platinum chemotherapy.

PURPOSE: Platinum agents cause DNA cross-linking and oxidative damage. Genetic polymorphisms of DNA repair genes are associated with differential DNA repair activity and may explain interindividual differences in overall survival after therapy with platinum agents for non-small-cell lung cancer (NSCLC). METHODS: We used polymerase chain reaction-restriction fragment length polymorphism to evaluate genetic polymorphisms of the XPD (Asp312Asn) and XRCC1 (Arg399Gln) DNA repair genes in 103 patients with stage III (54%) and IV (46%) NSCLC treated with platinum-based chemotherapy. RESULTS: Median age was 58 years (range, 32 to 77 years), 49% were females, and there were 86 deaths. Median follow-up period was 61.9 months. Median survival time (MST) was 14.9 months; by stage, MST was 28.6 months (IIIA), 16.0 months (IIIB), and 9.3 months (IV). Genotypes were not associated with stage. Increasing numbers of either XPD or XRCC1 variant alleles were associated with shorter overall survival (P =.003 and P =.07, respectively, by log-rank test). Similarly, when we compared combinations of variant alleles across both polymorphisms, we found that a greater number of variant alleles was associated with decreasing overall survival (P =.009, log-rank test). These polymorphisms independently predicted overall survival even after taking into account stage, performance status, and chemotherapy regimen. CONCLUSION: Genetic polymorphisms in XPD and XRCC1 may be important prognostic factors in platinum-treated patients with advanced NSCLC.

Adult↗
PubMed2004

Specific recruitment of SPA-1 to the immunological synapse: involvement of actin-bundling protein actinin.

SPA-1 is involved in the regulation of T cell activation in response to antigens through the control of Rap1 GTPase signaling. In this study, the subcellular localization of SPA-1 in the T cells was examined by using anti-SPA-1 antibody and GFP-SPA-1. While SPA-1 was detected diffusely at the surface cortical region in the floating unpolarized T cells, it was concentrated at the matrix-adhesion region with dense actin-cytoskeleton. Upon interaction with specific antigen-presenting cells, SPA-1 was highly concentrated at the immunological synapse closely co-localizing with actin. By yeast two-hybrid system, SPA-1 was shown to interact with an actin-bundling protein alpha-actinin, and it was indicated that SPA-1 co-localized with alpha-actinin at the immunological synapse. The results have suggested that SPA-1 in the T cells is selectively recruited to the immunological synapse with dense actin-cytoskeletal reorganization and keeps restraining the levels of Rap1GTP at the local TCR-signaling complex for the T cell activation.

Actinin↗
PubMed2004

Dietary intake of Cruciferous vegetables, Glutathione S-transferase (GST) polymorphisms and lung cancer risk in a Caucasian population.

OBJECTIVE: To evaluate possible interactions between dietary intake of cruciferous vegetables and the glutathione s-transferase mu and theta (GSTM1 and GSTT1) genotypes in lung cancer risk. METHODS: Hospital-based case-control study of 716 Caucasian lung cancer cases and 939 spouse and friend controls conducted in Boston, Massachussetts between 1992 and 2000. Dietary intake was collected through a food frequency questionnaire and blood was obtained for genotyping. Logistic regression models were adjusted for age, gender, total calories and smoking variables. RESULTS: Higher intakes of cruciferous vegetables reduced lung cancer risk among GSTM1 present individuals (odds ratio (OR)highest versus lowest tertile = 0.61, 95% confidence interval (CI) = 0.39-0.95) but not among GSTM1 null individuals (OR(highest versus lowest tertile) = 1.15, 95% CI = 0.78-1.68). We observed statistically significant interactions between GSTM1 and cruciferous vegetable intake overall (likelihood ratio test (LRT): p = 0.05) and among current smokers (LRT: p = 0.01). No significant interactions were observed for GSTT1 or the combined GSTM1/T1 genotype. CONCLUSIONS: In our study, higher cruciferous vegetable intake reduced lung cancer risk only among individuals with the GSTM1 present genotype. Our findings differed from prior studies that specifically assessed isothiocyanates found in cruciferous vegetables or evaluated Asian study populations with higher levels of cruciferous vegetable consumption.

Aged↗
PubMed2004

TLR4 Asp299Gly and Thr399Ile polymorphisms are very rare in the Chinese population.

Endotoxin is an important component of bio-aerosols that contribute to airway inflammation and airflow obstruction. Toll-like receptor 4 (TLR4) mediates the host response to bacterial lipopolysaccharide (LPS), and the Asp299Gly and Thr399Ile polymorphisms have been associated with the development of respiratory diseases. We hypothesized that TLR4 polymorphisms may be associated with a decline of lung function in cotton workers who were exposed continuously to endotoxin. We investigated these two polymorphisms in our 20-year longitudinal cohort of Han Chinese cotton and silk textile workers. The two polymorphisms were genotyped using TaqMan and PCR-restriction fragment length polymorphism methods. No homozygous or heterozygous variant genotypes of the Asp299Gly and Thr339Ile polymorphisms were detected in 491 samples of this population. Our results suggest that the TLR4 Asp299Gly and Thr339Ile polymorphisms are very rare in the Chinese population.

Adult↗
PubMed2004

Relationship between polymorphisms of genes encoding microsomal epoxide hydrolase and glutathione S-transferase P1 and chronic obstructive pulmonary disease.

BACKGROUND: Cigarette smoking is the major risk factor for chronic obstructive pulmonary disease (COPD). However, only 10% - 20% of chronic heavy cigarette smokers develop symptomatic disease. COPD is most likely the result of complex interactions between environmental and genetic factors. Genetic susceptibility to COPD might depend on the variations in enzyme activities that detoxify cigarette smoke products, such as microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST). In this study, we investigated the relationship between polymorphisms in the genes encoding mEH and glutathione S-transferase P1 (GSTP1) and COPD in a Chinese population. METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to find mEH polymorphism in exon 3 (Tyr113-->His), exon 4 (His139-->Arg) and GSTP1 polymorphism in exon 5 (Ile105-->Val) in 100 COPD patients and 100 age- and sex-matched healthy controls. RESULTS: The proportion of mEH exon 3 heterozygotes was significantly higher in patients with COPD than that in the control subjects (42% vs 32%). The odds ratio (OR) adjusted by age, sex, body mass index (BMI) and cigarette years was 2.96 (95% CI 1.24 - 7.09). There was no marked difference in very slow activity genotype versus other genotypes between COPD patients and the controls. When COPD patients were non-smokers, the OR of very slow activity genotype versus other genotypes was more than 1.00; and when COPD patients were smokers (current smokers and ex-smokers), the OR was less than 1.00. There was no significant difference in GSTP1 polymorphism adjusted by age, sex, BMI and smoking between COPD patients and the controls. CONCLUSIONS: mEH exon 3 heterozygotes might be associated with susceptibility to COPD in China. The interaction might exist between mEH genotype and smoke. The gene polymorphism for GSTP1 might not be associated with susceptibility to COPD in the Chinese population.

Aged↗
PubMed2004

Identification of chromosome regions associated with seedling vigor in rice.

Seedling vigor is important for optimum stand establishment in rice cropping. In this paper,a set of 264 F12 recombinant inbred lines (RILs) derived by single seed descent from a cross between Lemont (japonica) and Teqing (indica) was phenotyped for three seedling vigor related traits, including seed germination rate (GR), seedling shoot length and dry weight by the rolled paper towel tests. The phenotype data and a linkage map consisting of 198 DNA markers were combined to map quantitative trait loci (QTL) for seedling vigor by using a computer program QTLMapper1.0. A total of 13 putative main-effect QTL were detected. All of these QTL had much smaller effects on the traits with a mean R2 of 6.2%, ranging from 2.9% to 12.7%. As for digenic interaction, 18 pairs of epistatic loci with R2 > or = 5% were resolved with a mean R2 of 6.9% ,ranging from 5.1% to 11.8%, which was slightly larger than that of the main-effect QTL identified for the traits. The majority of the main-effect and epistatic loci detected for seedling vigor related traits were clustered in a few chromosome regions. Together, seven such chromosome regions (CRs), each with three or more seedling vigor main-effect and epistatic loci, were found to be highly associated with seedling vigor. These CRs can be classified into three types, i.e. M-CRs, E-CRs and ME-CRs. For some CRs just like CR(SV-6), the QTL within one CR were found to interact simultaneously with QTL within more than one other CRs to affect different seedling vigor related traits. The above results revealed that seedling vigor in rice is controlled by many loci, most of which have relatively small effects. Comparatively, epistasis as a genetic factor would be more important than main-effects of QTL for seedling vigor in rice. Nevertheless, the effects of the QTL are still large enough to be detected and in fact several chromosome regions were found to be highly associated with seedling vigor in very different populations as compared with previous studies. Molecular tagging of favorable alleles and marker-aided selection strategy may, therefore, be a promising approach to the improvement of rice seedling vigor.

Hybrid Vigor↗
PubMed2003

[Association between polymorphisms in the microsomal epoxide hydrolase (mEH) gene and chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the association between polymorphisms in the microsomal epoxide hydrolase (mEH) gene and susceptibility to chronic obstructive pulmonary disease (COPD) in a Chinese population. METHODS: Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were performed to genotype mEH polymorphisms in exon3 (Tyr113-->His) and exon4 (His139-->Arg) in 100 COPD patients and 100 age and sex matched healthy controls. RESULTS: (1) The proportion of mEH heterozygotes in exon3 was significantly higher in the patients with COPD than that in the control subjects (42% vs 32%). The odds ratio (OR) adjusted by age, sex, body mass index (BMI) and cigarettes years was 2.96 (95% CI 1.24 - 7.09). (2) There was no marked difference in very slow activity genotype versus other genotypes between COPD patients and controls. (3) When COPD patients were nonsmokers, the OR of very slow activity genotype versus other genotypes was more than 1.00, and when COPD patients were smokers (Current smokers and ex-smokers), the OR was less than 1.00. CONCLUSIONS: (1) mEH heterozygotes in exon3 might be associated with the susceptibility to COPD in China. (2) The interaction might be existed between mEH genotype and smoke.

Epoxide Hydrolases↗
PubMed2003

Association between self-reported environmental tobacco smoke exposure and lung cancer: modification by GSTP1 polymorphism.

Environmental Tobacco Smoke (ETS) exposure has been associated with lung cancer risk. ETS is composed of emissions from cigarette smoke and contains a higher concentration of tobacco smoke carcinogens than mainstream smoke. Polymorphisms in genes that metabolize tobacco smoke carcinogens have been studied as effect modifiers of the association between active smoking and lung cancer risk. GSTP1 is a polymorphic gene that encodes for GST pi, a detoxification enzyme and has a high expression in the lung. We investigated the association between ETS and lung cancer risk and the modification of this association by the GSTP1 polymorphism. Using a case-control design, individuals were genotyped for GSTP1 using PCR-RFLP techniques. All analyses were carried out using multiple logistic regression. The association between ETS exposure and lung cancer risk was evaluated in different strata based on smoking habits to evaluate the consistency of results. The effect of the GSTP1 polymorphisms on lung cancer risk was evaluated by considering the joint effect of having both an ETS exposure and the GSTP1 GG genotype compared to the absence of ETS exposure and the GSTP1 AA genotype as a reference group as well as doing stratified analysis by genotype. ETS exposure was associated consistently with higher lung cancer risk in all the strata considered. The adjusted odds ratios (AOR) evaluating the association between ETS and lung cancer risk for the different strata were: nonsmokers (Cases/Controls 66/413; AOR = 1.38; 95% CI = 0.78-2.43), ex-smokers (Cases/Controls 560/527; AOR = 1.66; 95% CI = 1.22-2.25), current smokers (Cases/Controls 415/219; AOR = 1.56; 95% CI = 1.00-2.41). The AORs for ex-smokers and light smoking subgroups were: ex-smokers who quit for 19 years or more (Cases/Controls 144/244; AOR = 2.64; 95% CI = 1.55-4.50), ex-smokers who quit for 10-19 years (Cases/Controls 141/128; AOR = 1.16; 95% CI = 0.66-2.04), ex-smokers who quit for 10 years or less (Cases/Controls 247/122; AOR = 1.45; 95% CI = 0.83-2.55) and participants who had <15 packyears and nonsmokers combined (Cases/Controls 143/640; AOR = 1.52; 95% CI = 1.02-2.28). Among those with the GSTP1 GG genotype the ETS-lung cancer risk association was greater than those with the GSTP1 AA genotype: nonsmokers (GSTP1 GG AOR = 7.84; 95% CI = 0.80-76.68; GSTP1 AA AOR = 1.15; 95% CI = 0.46-2.90), ex-smokers (GSTP1 GG AOR = 2.32; 95% CI = 0.90-5.96; GSTP1 AA AOR = 2.15; 95% CI = 1.34-3.44), current smokers (GSTP1 GG AOR = 1.75; 95% CI = 0.42-7.32; GSTP1 AA AOR = 1.32; 95% CI = 0.67-2.58) and participants who had <15 packyears and nonsmokers (GSTP1 GG AOR = 1.93; 95% CI = 0.54-6.97; GSTP1 AA AOR = 1.58; 95% CI = 0.83-3.01). We found that ETS exposure is associated with higher lung cancer risk. Furthermore, the presence of the GSTP1 GG genotype appears to enhance the magnitude of the association between ETS exposure and lung cancer. Larger studies will be needed to confirm these preliminary findings.

Adenocarcinoma↗
PubMed2003

AF-6 controls integrin-mediated cell adhesion by regulating Rap1 activation through the specific recruitment of Rap1GTP and SPA-1.

In the present study, we showed that SPA-1, a Rap1 GTPase-activating protein (GAP), was bound to a cytoskeleton-anchoring protein AF-6. SPA-1 and AF-6 were co-immunoprecipitated in the 293T cells transfected with both cDNAs as well as in normal thymocytes. In vitro binding studies using truncated fragments and their mutants suggested that SPA-1 was bound to the PDZ domain of AF-6 via probable internal PDZ ligand motif within the GAP-related domain. The motif was conserved among Rap1 GAPs, and it was shown that rapGAP I was bound to AF-6 comparably with SPA-1. RapV12 was also bound to AF-6 via the N-terminal domain, and SPA-1 and RapV12 were co-immunoprecipitated only in the presence of AF-6, indicating that they could be brought into close proximity via AF-6 in cells. Immunostaining analysis revealed that SPA-1 and RapV12 were co-localized with AF-6 at the cell attachment sites. In HeLa cells expressing SPA-1 in a tetracycline-regulatory manner, expression of AF-6 inhibited endogenous Rap1GTP and beta(1) integrin-mediated cell adhesion to fibronectin in SPA-1-induced conditions, whereas it affected neither of them in SPA-1-repressed conditions. These results suggested that AF-6 could control integrin-mediated cell adhesion by regulating Rap1 activation through the recruitment of both SPA-1 and Rap1GTP via distinct domains.

Animals↗
PubMed2003

P53 (codon 72) and P21 (codon 31) polymorphisms alter in vivo mRNA expression of p21.

p21 (Waf1/Cip1) is a downstream target of p53. We evaluated the association between p21 polymorphism (codon 31), p53 polymorphism (codon 72) and their corresponding in vivo mRNA expression. In this study, p21 and p53 genetic polymorphisms (using standard PCR-RFLP techniques) and p21 and p53 gene expressions (using a radiolabelled ribonuclease protection assay (RPA) technique) were evaluated in the peripheral leukocytes of 84 individuals (63 with lung cancer). Log-transformed values of mRNA expression by RPA, which approximated a normal distribution, were analyzed. p53 genotypes did not correlate with p53 mRNA log-expression (P>0.05 for all comparisons), but the Pro allele variants of p53 were associated with a significant decrease in mRNA log-expression of its downstream target, p21. The variant Arg allele of p21 was also associated with a significant decrease in p21 mRNA log-expression. When individuals with at least one variant allele of both p53 and p21 (double-variants) were compared with all other genotype groups, these double-variants had significantly lower log-expression of p21 (P<0.005 by both t-tests (crude) and linear regression analyses (adjusted)). This is translated into an approximate 48% reduction in the geometric mean of the mRNA expression of the double-variants, when compared with all other groups. Results were consistent in both patients with lung cancer (n=63) and in normal controls (n=21). In conclusion, the presence of a p53 Pro allele and/or p21 Arg allele is associated with lower downstream target gene expression of p21.

Aged↗
PubMed2003

Smoking and the risk of lung cancer: susceptibility with GSTP1 polymorphisms.

BACKGROUND: GSTP1 is a gene that helps detoxify foreign substances in the body. Functional polymorphisms of GSTP1 have been studied as risk factors for lung cancer. Past studies have compared the effect of the "at risk" polymorphism in two strata of smoking pack-years (usually defined by the median among controls). We examined the interaction between GSTP1 polymorphisms and cumulative exposure to smoking and their association with lung cancer risk. METHODS: Data are from a large hospital-based case-control study of persons treated for primary lung cancer at the Massachusetts General Hospital since 1992. Controls were drawn from friends and nonrelated family members. We genotyped 1,042 cases and 1,161 controls for GSTP1 using polymerase chain reaction-restriction fragment length polymorphism techniques. FINDINGS: The GSTP1 GG genotype approximately doubled the lung cancer risk associated with pack-years. This interaction was stronger among current smokers. At 26 pack-years (median among controls with a smoking history), the adjusted odds ratio for the association between pack-years and lung cancer risk was 13 (95% confidence interval = 6.5-25) among current smokers with the GSTP1 GG genotype compared with 6.1 (95% confidence interval = 4.9-7.5) among those with the GSTP1 AA genotype. CONCLUSIONS: GSTP1 GG increases the lung cancer risk associated with pack-years of smoking.

Adult↗
PubMed2003

Percutaneous sonographically guided microwave coagulation therapy for hepatocellular carcinoma: results in 234 patients.

OBJECTIVE: The objective of our study was to evaluate the long-term results of percutaneous microwave coagulation therapy for the treatment of hepatocellular carcinoma in a large patient population. SUBJECTS AND METHODS: Survival rates were determined in 234 patients with 339 nodules of hepatocellular carcinoma who had undergone percutaneous microwave coagulation therapy (208 men, 26 women; mean age, 54.8 years; mean tumor size, 4.1 +/- 1.9 cm; range, 1.2-8.0 cm; mean follow-up period, 27.9 months). Patients were those who had been rejected as candidates for surgery by the surgery department, who fit our study's criteria, and who agreed to participate. After baseline imaging studies were performed, the patients were followed up using the same combination of imaging (sonography, CT, or MR imaging) and posttreatment biopsy. RESULTS: After percutaneous microwave coagulation therapy, color Doppler flow signals disappeared in 92.0% (263/286) of the lesions. No enhancement was apparent in 89.2% (190/213) and 89.1% (41/46) of the lesions on contrast-enhanced CT and MR imaging, respectively. Posttreatment biopsies of 194 nodules showed no evidence of surviving tumor tissue in 180 nodules (92.8%). Resections of six lesions revealed complete tumor necrosis in five. The 1-, 2-, 3-, 4-, and 5-year cumulative survival rates were 92.70%, 81.60%, 72.85%, 66.37%, and 56.70%, respectively. The relationships between survival curves and the degree of hepatocellular carcinoma tumor differentiation and between survival curves and tumor size were statistically significant (p = 0.021). No severe complications were seen. CONCLUSION: Sonographically guided microwave coagulation proved to be safe and effective for the treatment of hepatocellular carcinoma. This therapy resulted in a high percentage of cases without evidence of residual tumor and satisfactory long-term results.

Administration, Cutaneous↗
PubMed2003

Prognostic factors for percutaneous microwave coagulation therapy of hepatic metastases.

OBJECTIVE: Microwave-induced tissue coagulation is a new approach for the local ablation of hepatic metastases. The purposes of the study were to analyze therapeutic results and those influencing factors that might be used to predict survival after percutaneous microwave coagulation therapy. SUBJECTS AND METHODS. From July 1995 to March 2002, 74 patients with 149 hepatic metastases were treated with percutaneous microwave coagulation therapy under sonographic guidance. The largest metastasis in each patient ranged from 0.7 to 6.8 cm (mean, 3.12 cm; SD, 1.81 cm). Survival rates and influencing factors were analyzed. RESULTS: The cumulative survival rates of all 74 patients were 91.4% at 1 year, 59.5% at 2 years, 46.4% at 3 years, 29% at 4 years, and 29% at 5 years. Patient age (p = 0.46) and sex (p = 0.12) and site of primary malignancies (p = 0.58) were not related to prognosis, whereas tumor grade (p = 0.01), number of metastases (p = 0.00), tumor size (p = 0.03), and local recurrence or new metastasis (p = 0.00) significantly affected survival as single independent factors. Multivariate analysis revealed that tumor grade (p = 0.03), number of metastases (p = 0.025), and local recurrence or new metastasis (p = 0.04) each had a significant effect on survival. No severe complications occurred. CONCLUSION: The probability of long-term survival for patients with one or two metastases, well-differentiated tumors, and without recurrence or new metastasis may be significantly higher than for other patients.

Adult↗
PubMed2003

Polymorphisms in the DNA repair genes XRCC1 and ERCC2, smoking, and lung cancer risk.

XRCC1 (X-ray cross-complementing group 1) and ERCC2 (excision repair cross-complementing group 2) are two major DNA repair proteins. Polymorphisms of these two genes have been associated with altered DNA repair capacity and cancer risk. We have described statistically significant interactions between the ERCC2 polymorphisms (Asp312Asn and Lys751Gln) and smoking in lung cancer risk. In this case-control study of 1091 Caucasian lung cancer patients and 1240 controls, we explored the gene-environment interactions between the XRCC1 Arg399Gln polymorphism, alone or in combination with the two ERCC2 polymorphisms, and cumulative smoking exposure in the development of lung cancer. The results were analyzed using logistic regression models, adjusting for relevant covariates. Overall, the adjusted odds ratio (OR) of XRCC1 Arg399Gln polymorphism (Gln/Gln versus Arg/Arg) was 1.3 [95% confidence interval (CI), 1.0-1.8]. Stratified analyses revealed that the ORs decreased as pack-years increased. For nonsmokers, the adjusted OR was 2.4 (95% CI, 1.2-5.0), whereas for heavy smokers (>/=55 pack-years), the OR decreased to 0.5 (95% CI, 0.3-1.0). When the three polymorphisms were evaluated together, the adjusted ORs of the extreme genotype combinations of variant alleles (individuals with 5 or 6 variant alleles) versus wild genotype (individuals with 0 variant alleles) were 5.2 (95% CI, 1.7-16.6) for nonsmokers and 0.3 (95% CI, 0.1-0.8) for heavy smokers, respectively. Similar gene-smoking interaction associations were found when pack-years of smoking (or smoking duration and smoking intensity) was fitted as a continuous variable. In conclusion, cumulative cigarette smoking plays an important role in altering the direction and magnitude of the associations between the XRCC1 and ERCC2 polymorphisms and lung cancer risk.

Adult↗
PubMed2003

[Experimental pathological study of subacute intoxication by Dioscorea bulbifera L].

OBJECTIVE: To study the pathological change and the toxic mechanism of Dioscorea bulbifera L in mice. METHODS: Sixty ICR mice were randomly assigned to four groups poisoned respectively with 200% Dioscorea bulbifera L of 1/4 LD50, 1/10LD50, 1/30LD50 and a control group treated with distilled water by oral administration. All animals were pathologically examined with LM and some of them were examined with TEM when the mice died during the experiment or the survival mice were sacrificed after thirty days. RESULTS: The pathological changes showed fatty change and the increasing glycogen of liver cells; degeneration and necrosis of the epithelia of uriniferous tubules. The serum BUN and ALT of the experimental groups mice were higher than that of control group. Enzyme histochemical staining showed the decreasing activity of G-6-P and SDH in the liver cells in the experimental groups. CONCLUSION: The experiment suggests that the target organs were liver and kidney. The toxic mechanism of Dioscorea bublifera L was the damage of the mitochondrional and endoplasmic reticulum membrane directly. As a result, the activity of the SDH and G-6-P decreased, the metabolism was affected.

Animals↗
PubMed2003

[Association between polymorphisms in the gene coding for glutathione S-transferase P1 and chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the association between polymorphisms in the gene coding for glutathione S-transferase P1 (GSTP1) and susceptibility to chronic obstructive pulmonary disease (COPD) in a Chinese population. METHODS: This was a pilot study of the molecular epidemiology in patients with COPD. The research design was a case-control study. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were performed to genotype GSTP1 polymorphisms in exon 5 in 100 COPD patients and 100 age and sex matched healthy controls. Logistic regression analysis method was used to calculate the odds ratio (OR) and the 95% confidence interval (CI). RESULT: There was no significant difference in GSTP1 polymorphisms adjusted by age, sex, body mass index and smoking between COPD patients and controls. CONCLUSION: The gene polymorphism for GSTP1 was not associated with susceptibility to COPD in the Chinese population.

Aged↗