[Influence of social support and coping style on chronic post-traumatic stress disorder after floods].

OBJECTIVE: To explore the long-term prognosis and influence of social support and coping style of patients with post-traumatic stress disorder (PTSD) after suffering from floods. METHODS: Patients suffered PTSD due to Dongting lake flood in 1998 were selected through cluster random sampling. PTSD scale civilian version (PCL-C) was used to examine and diagnose the participants in this study. PTSD was then evaluated by the social support rating scale (SSRS) and the simple coping style questionnaire (SCSQ). RESULTS: Among all the 120 subjects, 14(11.67%) of them were diagnosed as having PTSD. Compared with the rehabilitation group, scores on subjective support, objective support, total social support and positive coping, total of coping style from the non-rehabilitation group all appeared significant low (P<0.05). Data from the multivariate logistic regression showed that social support (OR=0.281, 95% CI: 0.117-0.678) and coping style (OR= 0.293, 95% CI: 0.128-0.672) were protective factors of the chronic PTSD after the floods while disaster experience (OR=1.626, 95%CI: 1.118-2.365) appeared as a risk factor. CONCLUSION: Chronic PTSD developed after the floods called for attention. Better social support, positive coping style could significantly improve the long-term prognosis of patients with PTSD after the floods.

Quantitative proteomic analysis of formalin-fixed, paraffin-embedded clear cell renal cell carcinoma tissue using stable isotopic dimethylation of primary amines.

BACKGROUND: Formalin-fixed, paraffin-embedded (FFPE) tissues represent the most abundant resource of archived human specimens in pathology. Such tissue specimens are emerging as a highly valuable resource for translational proteomic studies. In quantitative proteomic analysis, reductive di-methylation of primary amines using stable isotopic formaldehyde variants is increasingly used due to its robustness and cost-effectiveness. RESULTS: In the present study we show for the first time that isotopic amine dimethylation can be used in a straightforward manner for the quantitative proteomic analysis of FFPE specimens without interference from formalin employed in the FFPE process. Isotopic amine dimethylation of FFPE specimens showed equal labeling efficiency as for cryopreserved specimens. For both FFPE and cryopreserved specimens, differential labeling of identical samples yielded highly similar ratio distributions within the expected range for dimethyl labeling. In an initial application, we profiled proteome changes in clear cell renal cell carcinoma (ccRCC) FFPE tissue specimens compared to adjacent non-malignant renal tissue. Our findings highlight increased levels of glyocolytic enzymes, annexins as well as ribosomal and proteasomal proteins. CONCLUSION: Our study establishes isotopic amine dimethylation as a versatile tool for quantitative proteomic analysis of FFPE specimens and underlines proteome alterations in ccRCC.

Differential effects of diethylstilbestrol and 2,3,7,8-tetrachlorodibenzo-p-dioxin on thymocyte differentiation, proliferation, and apoptosis in bcl-2 transgenic mouse fetal thymus organ culture.

Both the estrogenic drug diethylstilbestrol (DES) and the pervasive environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibit thymocyte development. The mechanisms by which either agent induces thymic atrophy are still undetermined. We previously found that TCDD and DES inhibited C57BL/6 murine fetal thymocyte organ cultures (FTOC) at different stages of development. Now, using bcl-2 transgenic (TG) mice, we have further investigated their effects on FTOC proliferation, differentiation, maturation, and apoptosis. As with C57BL/6 mice, thymocyte development in C3H/bcl-2 FTOCs was inhibited by either TCDD (10 nM) or DES (20 microM) in both bcl-2 TG- and TG+ littermates. However, the percentage reduction of cell number induced by DES in bcl-2 TG+ FTOCs was significantly less than the level of inhibition in TG- FTOCs. There was no difference in the level of reduction from TCDD-exposed TG+ or TG- FTOC. Whereas TCDD increased production of mature CD8 cells in either strain, DES mainly yielded cells in the CD4(-)CD8(-)(DN) stage in TG- mice. The anti-apoptotic bcl-2 transgene overcame some DES blocking of DN thymocyte development, allowing more cells to differentiate into CD4 single-positive cells. Analysis of cell cycle showed that TCDD inhibited entry into S phase, whereas DES blocked cell cycling in the G2/M phase. TCDD did not induce detectable apoptosis in FTOC. However, unlike the effects of 17 beta-estradiol (E2) in vivo, DES induced apoptosis in the TG- FTOC, and these apoptotic cells were mainly in the DN subpopulation. This apoptosis could be prevented by the overexpression of bcl-2 in the TG+ mice. Our results demonstrate that, in addition to inhibition of fetal thymocytes at different stages of development by TCDD and DES, DES also induces thymic atrophy by both bcl-2-inhibitable apoptosis and by inducing cell cycle arrest in G2/M in the latest stage in the stem cell compartment. TCDD, on the other hand, does not induce apoptosis, but inhibits entry into cell cycle in the earliest stage in the stem cell compartment.

2,3,7,8-Tetrachlorodibenzo-p-dioxin and diethylstilbestrol affect thymocytes at different stages of development in fetal thymus organ culture.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and estrogen induce thymic atrophy and alter thymocyte development. In the present study we investigate whether TCDD and the synthetic estrogen diethylstilbestrol (DES) alter intrathymic development by the same or different mechanisms. We compared the effects of TCDD and DES on thymocyte development in fetal thymus organ culture (FTOC) and found that both compounds caused a reduction in cell yield. TCDD- and DES-treated FTOCs yielded fewer CD4 + CD8+ double-positive cells. However TCDD treatment also led to a greater percentage of cells in the CD8+ single-positive compartment. At lower dioxin concentrations, our results demonstrated an actual increase in CD8+ cells, whereas DES-treated fetal thymocytes were mainly enriched in CD4-CD8- double-negative cells. More alpha beta-TCR+ positive cells were seen in TCDD- but not in DES-exposed cultures. Furthermore, in this study we found that TCDD and DES also alter intrathymic development at different stages in the CD4-CD8- double-negative compartment. TCDD induced a relative increase in c-kit + CD44 + CD25-HSA-thymocytes, while DES induced an relative increase in c-kit-CD44-CD25 + HSA+ cells. RT-PCR revealed that TCDD reduced RAG-1, RAG-2, and TdT gene expression in the CD4-CD8- double-negative thymocytes. Co-treatment by TCDD and DES in FTOC yielded a mixture of effects induced by each agent. Taken together, our results demonstrate that TCDD and DES affect thymocytes at different stages of development, suggesting distinct mechanisms for induction of thymic atrophy.

Cytokine gene expression during ontogeny in murine thymus on activation of the aryl hydrocarbon receptor by 2,3,7,8-tetrachlorodibenzo-p-dioxin.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) binds and activates the aryl hydrocarbon receptor (Ah-R), an endogenous transcription factor that is expressed in the thymus. TCDD exposure leads, among other effects, to thymus atrophy and immunosuppression. We previously analyzed the interference of TCDD with differentiation processes in fetal thymus organ cultures and found that in the presence of TCDD, the proliferation rate of immature (CD4- CD8- and CD4- CD8+ HSA+) thymocytes is inhibited, whereas the maturation along the CD4/CD8 path is accelerated. Moreover, the differentiation of thymocytes is skewed by TCDD at < or = 40% (compared with approximately 15% without TCDD) of the CD8 single-positive subset of future cytotoxic T cells, and apparently more cells audition for and pass positive selection. The fetal murine thymus expresses functional Ah-R mRNA, as shown by reverse transcription-polymerase chain reaction and TCDD-inducible CYP1A1 and CYP1B1 expression. Because the differentiation of thymocytes is to a considerable extent controlled by cytokines and many cytokine genes are potential targets of the Ah-R due to Ah-R-binding elements (xenobiotic response elements) in their promoters, we analyzed the cytokine expression in fetal thymus organ culture exposed to TCDD. Fetal thymi were cultured from gestation day 15 for < or = 8 days, thus covering ex vivo the period after population of the thymus anlage until birth. We show with semiquantitative reverse transcription-polymerase chain reaction that more interleukin (IL)-1beta, IL-2, IL-6, tumor growth factor (TGF)-beta3, and tumor necrosis factor-alpha are produced in TCDD-exposed thymi, whereas other cytokines (e.g., TGF-beta1, PAI-2, or IL-4) are only slightly up- and down-modulated during the culture period or not modulated at all (e.g., IL-1beta, IL-7, interferon-gamma, and TGF-beta2).

Identification of dioxin-responsive elements (DREs) in the 5' regions of putative dioxin-inducible genes.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an exogenous ligand for the cytosolic aryl hydrocarbon receptor (AhR), a ligand-inducible transcription factor whose exact physiological role remains elusive. TCDD has been shown to modulate the expression of a large array of genes, albeit often indirectly, by demonstration of protein or mRNA upregulation. Here, by computer analysis of available promoter sequences, we identify dioxin-responsive elements in the promoter regions of many putative AhR regulated and therefore dioxin-inducible genes.

Evidence for the promotion of positive selection of thymocytes by Ah receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin.

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a ligand for the arylhydrocarbon receptor (Ah receptor), abundant in the murine thymus. In the thymus immunocompetent T cells develop. Upon exposure of murine fetal thymi in organ cultures to TCDD the distribution of mature and immature thymocytes is skewed towards apparently mature, prospective cytotoxic cells of the CD4-CD8+T cell receptor+ phenotype. The normally abundant CD4+ CD8+ cells are decreased. Proliferation of the most immature thymocyte subpopulations is inhibited and maturation of thymocytes appears accelerated by TCDD. Eventually the thymocyte number is significantly decreased. Selective treatment of stroma cells showed them to be the primary target cells of TCDD action. Thymus stroma plays a pivotal role in thymocyte maturation and is indispensable for the selection of thymocytes bearing T cell receptors specific for foreign antigen in the context of self. We tested whether the effects of TCDD on thymocyte differentiation and maturation has further consequences for the selection processes by analysing (a) the repertoire of V beta genes used as a measure for negative selection and (b) the expression of CD69 and bcl-2 by thymocytes as a parameter of positive selection. Our data indicate that TCDD does not cause gross disturbance of negative selection but provide evidence for more cells auditioning for positive selection by TCDD exposure.

CD8 thymocytes derived from 3,3',4,4'-tetrachlorobiphenyl-exposed fetal thymi possess killing activity.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and its congeners such as 3,3',4,4'-tetrachlorobiphenyl (TCB) cause immunosuppression in experimental animals and possibly in humans. In previous studies we found that exposure of murine fetal thymic organ cultures (FTOCs) to TCDD or TCB reduced the proliferative capacity of immature thymocytes. At the same time, the kinetics of thymocyte maturation was changed, and thymocyte differentiation was skewed toward CD4-CD8+ phenotypically mature cells. Here, we analyze the biological activities of thymocytes generated in TCB-exposed fetal thymus to determine whether these cells are also functionally mature. C57BL/6 fetal thymic lobes from Day 15 of gestation were explanted and grown for 8 days in FTOC in the presence or absence of 3.3 microM TCB. Then, the functions of total thymocytes or sorted subsets thereof were tested. We found that thymocytes from TCB-exposed lobes responded to stimulation by Con A or anti-CD3 and possessed cytotoxic activity upon cultivation in the presence of H-2 allogenic spleen cells. Further analysis showed that the overall cytotoxic activity of thymocytes was mainly due to the CD4-CD8+ cells. Our results suggest that the CD4-CD8+ cells, which are generated in substantially increased numbers in TCB-exposed fetal thymus, are functionally competent cells.

3,3',4,4'-Tetrachlorobiphenyl inhibits proliferation of immature thymocytes in fetal thymus organ culture.

The environmental pollutant 3,3',4,4'-tetrachlorobiphenyl (TCB) leads to thymic atrophy and immunosuppression, the former possibly causing the latter. TCB binds to the cytosolic aryl-hydrocarbon receptor (AhR) and transforms it into a DNA-binding state. The development of fetal thymocytes is severely affected by TCB and other AhR-binding xenobiotics, leading to a skewed pattern of thymocyte maturation stages. Murine thymocyte proliferation after exposure to TCB was studied in fetal thymus organ culture (FTOC). C57BL/6 fetus thymic lobes from day 15 of gestation were explanted and grown for 2, 4, 6, and 8 days in organ culture in the presence or absence of 3.3 microM TCB. Subsets of thymocytes were defined by CD4 and CD8 surface markers, and their cell cycle was analysed by DNA staining with 7-amino-actinomycin D (7-AAD). Exposure of fetal thymi in vitro to 3.3 microM TCB significantly reduced the total number of thymocytes, and fewer thymocytes were in S/G2M phase. The inhibition of cell proliferation induced by TCB treatment affected mainly the CD4-CD8- (double-negative, DN) and CD4-CD8+ (single-positive, SP) subsets, and these inhibition appeared mainly in more immature thymocytes, i.e. DNCD3- and CD8+CD3- subpopulations, whereas no effect of TCB on CD4+CD8+ (double-positive, DP) cell proliferative activity was observed. Analysis of the relation of cell proliferation and development of subsets in differentiating fetal thymocytes suggests that TCB enhanced thymocyte differentiation into mature CD8+ cells.

Toxicological studies on the organophosphorous insecticide methyl-ISP.

Methyl-ISP, a newly developed organophosphorous insecticide, is used in China to treat and protect plants from pest infestation. Our studies demonstrated that methyl-ISP is metabolized rapidly in rat and mouse. Its toxicity was low, no obvious accumulative toxicity, chronic toxicity, teratogenicity, mutagenicity, reproductive toxicity or delayed neurotoxicity could be observed. It is therefore concluded that methyl-ISP is relatively safe to animals and human subjects. methyl-ISP is now employed to replace the other commonly used insecticide hexachlorobenzene (666) in agriculture. A preliminary study was performed to elucidate the mechanism of intoxication at subcellular levels.