Abstract: Objective - - To establish a pre column derivatization high performance liquid chromatography method for detecting Methods dimethyl sulfate (DMS) in workplace air. DMS in workplace air was collected with mercaptopyridine impregnated （ silicone tube. The derivative of DMS and mercaptopyridine was eluted by mobile phase phase A: water, phase B: acetonitrile, ∶ the volume ratio was 40 60) , and separated with a C18 column, then detected with diode array detector and quantitated by a Results - standard curve. The linear range of DMS was 0.17 40.00 mg/L, with the correlation coefficient of 0.999 95. The detection limit and the lower limit of quantitation were 0.05 and 0.17 mg/L respectively. The minimum detection concentration and minimum quantitation concentration were 0.02 and 0.04 mg/m³, respectively (air sample volume of 4.5 L, 1.0 mL sample - - - solution). The average desorption efficiency was 98.40% 102.00%. The within run and between run relative standard deviations - - were 0.61% 3.92% and 1.71% 6.00%, respectively. The samples could be stored at room temperature for at least 14 days. Conclusion This method can be used to detect DMS in workplace air.

BACKGROUNDMyocardial apoptosis is involved in the pathogenesis of sepsis-related myocardial depression. However, the underlying mechanism remains unknown. This study investigated the role of mitochondrial damage and mitochondria-induced oxidative stress during cardiac apoptosis in septic rats.

METHODSSeventy-two Sprague-Dawley rats were randomly divided into a control group and septic group receiving lipopolysaccharide injection. Heart tissue was removed and changes in cardiac morphology were observed by light microscopy and scanning electron microscopy. In situ apoptosis was examined using terminal transferase-mediated dUTP nick end-labeling assay and nuclear factor-kappa B activation in myocardium by Western blotting to estimate myocardial apoptosis. Appearance of mitochondrial cristae and activation of cytochrome C oxidase were used to evaluate mitochondrial damage. Oxidative stress was assessed by mitochondrial lipid and protein oxidation, and antioxidant defense was assessed by mitochondrial superoxide dismutase and glutathione peroxidase activity.

RESULTSSepsis-induced inflammatory cell infiltration, myocardium degeneration and dropsy were time-dependent. Expanded capillaries were observed in the hearts of infected rats 24 hours post-challenge. Compared with sham-treated rats, the percentage of cell apoptosis increased in a time-dependent manner in hearts from septic rats at 6 hours, 12 hours and 24 hours post-injection (P < 0.05). The expression of nuclear factor-kappa B p65 decreased gradually in the cytosol and increased in the nucleus during sepsis, indicating that septic challenge provoked the progressive activation of nuclear factor-kappa B. Mitochondrial cristae and activation of cytochrome C oxidase increased in a time-dependent manner. Both superoxide dismutase and glutathione peroxidase activities decreased, while mitochondrial lipid and protein oxidation increased between 6 and 24 hours after lipopolysaccharide challenge.

CONCLUSIONSSeptic challenge induced myocardial apoptosis and mitochondrial damage. Furthermore, mitochondrial damage via alteration of defenses against reactive oxygen species might play an important role in myocardial apoptosis during sepsis.

Animals ; Apoptosis ; physiology ; Male ; Mitochondria, Heart ; metabolism ; pathology ; Myocardium ; metabolism ; pathology ; Oxidative Stress ; physiology ; Rats ; Rats, Sprague-Dawley ; Sepsis ; metabolism ; physiopathology

OBJECTIVETo investigate possible association between the single nucleotide polymorphisms (SNPs) of transforming growth factor beta3 (TGF-beta3) gene and essential hypertension (EH) in Chinese.

METHODSThe promoter region, exons, as well as part of the introns of TGF-beta3 gene were sequenced by a fluorescent labeling automatic sequencing method to detect and characterize the SNPs in 24 DNA samples from a Chinese population. Then we conducted a case-control study using 396 patients with hypertension (case) and 214 nomortensive subjects (control). The three SNPs including Thr63Asn, SS5608219 and SS5608220 were genotyped by PCR-RFLP or real-time allele-specific PCR in subjects studied.

RESULTSSeven SNPs in the exons, introns and 3'untranslated region (3'UTR) of TGF-beta3 gene were identified. Among them, 2 SNPs were found to be novel genetic variants and one of the two located in the exon 1 and produced substitution of amino acid. However, no differences were found between hypertensives and nomortensives in genotype distribution and allele frequency of SS5608219, Thr63Asn or SS5608220 polymorphisms.

CONCLUSIONSTwo novel SNPs of TGF-beta3 gene were identified in Chinese. One of them produces a threonine to asparagines substitution in codon 63 (Thr63Asn). But no association was found between TGF-beta3 gene polymorphisms and EH in Chinese.

Aged ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Exons ; Female ; Genotype ; Humans ; Hypertension ; genetics ; Middle Aged ; Polymorphism, Single Nucleotide ; Transforming Growth Factor beta3 ; genetics

Objective: As cytotoxic T cells, CD8+ T lymphocytes can kill tumor cells by releasing perforin and other effector molecules, but the correlation between their infiltration level and the prognosis of colorectal cancer varies in previous studies. This study aims to explore the distribution of CD8+T cells in tumor center and invasive margin of colorectal cancer, and to analyze their correlation with the prognosis of patients. Methods: A retrospective cohort study was used to analyze the clinicopathological features of 221 patients with colorectal cancer from the colorectal cancer pathological database of the Sixth Affiliated Hospital of Sun Yat-sen University between 2009 and 2012. Case inclusion criteria: (1) colorectal cancers confirmed by postoperative pathology; (2) patients with follow-up data. Exclusion criteria: (1) multiple primary cancers; (2) inflammatory bowel disease, Lynch syndrome or familial adenomatous polyposis; (3) no available paraffin slides; (4) patients receiving preoperative radiotherapy or chemotherapy. A total of 221 patients met the criteria. Immunohistochemical staining was used to count the CD8+ T cells in tumor center and invasive margin in the paraffin slides. Meanwhile the relative expression of CD8B gene in 22 fresh freeze samples of colorectal cancer was detected. Then the correlation of the expression with CD8+T cell density was examined. The patients were divided into high and low infiltration groups according to the level of CD8+T cells. Log-rank test was applied to compare the overall survival of the two groups of patients, and Cox regression analysis was used to adjust the prognostic significance of CD8+T cell infiltration. Results: There were 118 males and 103 females. In 221 slides, CD8+T cells infiltrating in invasive margin were more than those in tumor center [median (range): 37(0-141) / field vs. 14(0-106) / field, Z=-11.985, P<0.001], and the number of CD8+T cell in the tumor center was positively correlated with those in invasive margin (r=0.610, P<0.001). The number of CD8+ T cell in tumor center was positively correlated with the relative expression of CD8B gene (r=0.524, P=0.012). Survival analysis showed that the overall survival of the high infiltration group was better than that of the low infiltration group both in tumor center and invasive margin (median survival: 84.1 months vs. 73.5 months, P<0.001; 84.2 months vs. 75.9 months, P=0.002). Cox regression analysis revealed that high CD8+T cell infiltration in tumor center was an independent protective factor of overall survival (HR=0.369, 95% CI: 0.168-0.812, P=0.013). Conclusions: The infiltration level of CD8+T cells in tumor center is lower than that in invasive margin, and they are positively correlated. The level of CD8+ T cell infiltration in tumor center is related to overall survival and can be used as a potential pronostic marker.
CD8-Positive T-Lymphocytes ; Colorectal Neoplasms ; Humans ; Prognosis ; Retrospective Studies