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Background Multidrug-resistant tuberculosis (MDR-TB) is a major public health problem. Early diagnosis of MDR-TB patients is essential for minimizing the risk of Mycobacterium tuberculosis (MTB) transmission. The conventional drug susceptibility testing (DST) methods for detection of drug-resistant M.tuberculosis are laborious and cannot provide the rapid detection for clinical practice. Methods The aim of this study was to develop a pyrosequencing approach for the simultaneous detection of resistance to rifampin (RIF), isoniazid (INH), ethambutol (EMB), streptomycin (SM), ofloxacin (OFL) and amikacin (AMK) in M. tuberculosis clinical isolates and sputum samples from re-treatment pulmonary tuberculosis ( PTB) patients. We identified the optimum conditions for detection mutation of rpoB, katG, rpsl, embB, gyrA and rrs gene by pyrosequencing. Then this approach was applied to detect 205 clinical isolates and 24 sputum samples of M. tuberculosis from re-treatment PTB patients. Results The mutations of rpoB and gyrA gene were detected by pyrosequencig with the SQA mode, and the mutations of katG, rpsl, embB, gyrA and rrs gene were detected by pyrosequencing with SNP mode. Compared with the Bactec MGIT 960 mycobacterial detection system, the accuracy of pyrosequencing for the detection of RIF, INH, EMB, SM, AMK and OFL resistance in clinical isolates was 95.0%, 79.2%, 70.3%, 84.5%, 96.5% and 91.1%, respectively. In sputum samples the accuracy was 83.3%, 83.3%, 60.9%, 83.3%, 87.5% and 91.7%, respectively. Conclusions The newly established pyrosequencing assay is a rapid and high-throughput method for the detection of resistance to RIF, INH, SM, EMB, OFL and AMK in M.tuberculosis. Pyrosequencing can be used as a practical molecular diagnostic tool for screening and predicting the resistance of re-treatment pulmonary tuberculosis patients. [ABSTRACT FROM AUTHOR]

The MHC class II-restricted antigen processing pathway presents antigenic peptides acquired in the endocytic route for the activation of CD4+ T cells. Multiple cancers express MHC class II, which may influence the anti-tumor immune response and patient outcome. Low MHC class II expression is associated with poor survival in diffuse large B-cell lymphoma (DLBCL), the most common form of aggressive non-Hodgkin lymphoma. Therefore, we investigated whether gamma-interferon-inducible lysosomal thiol reductase (GILT), an upstream component of the MHC class II-restricted antigen processing pathway that is not regulated by the transcription factor class II transactivator, may be important in DLBCL biology. GILT reduces protein disulfide bonds in the endocytic compartment, exposing additional epitopes for MHC class II binding and facilitating antigen presentation. In each of four independent gene expression profiling cohorts with a total of 585 DLBCL patients, low GILT expression was significantly associated with poor overall survival. In contrast, low expression of a classical MHC class II gene, HLA-DRA, was associated with poor survival in one of four cohorts. The association of low GILT expression with poor survival was independent of established clinical and molecular prognostic factors, the International Prognostic Index and the cell of origin classification, respectively. Immunohistochemical analysis of GILT expression in 96 DLBCL cases demonstrated variation in GILT protein expression within tumor cells which correlated strongly with GILT mRNA expression. These studies identify a novel association between GILT expression and clinical outcome in lymphoma. Our findings underscore the role of antigen processing in DLBCL and suggest that molecules targeting this pathway warrant investigation as potential therapeutics. [ABSTRACT FROM AUTHOR]

Reactions of the aminochlorosilane RSiHCl2and disilane R2Si2HCl3(R = (2,6-iPr2C6H3)(SiMe3)N) with an excess of 1,3-bis(tert-butyl)imidazol-2-ylidene resulted in the silylation of the NHC while reaction with the less hindered 1,3-diisopropyl-4,5-dimethyl-imidazol-2-ylidene yielded an NHC-stabilized aminochlorosilylene. [ABSTRACT FROM AUTHOR]

Reaction of cyclic diaminochlorosilanes with 1,3-bis(tert-butyl)imidazol-2-ylidene resulted in the facile formation of the corresponding stable and transient diaminosilylenes. This novel dehydrochlorination route could be applied for the generation of four- and five-membered N-heterocyclic silylenes with a range of different substituents under very mild conditions. Activation of an olefinic C−H bond and reduction of a cyclic diaminochlorosilane have been observed for these new transient silylenes. [ABSTRACT FROM AUTHOR]

The straightness of the 100-meter rail after straightening is directly affected by the bending deformation during cooling before straightening, and the analysis of the temperature field in the cooling process is the basis of studying the bending deformation. By analyzing the heat boundary conditions in the cooling process, the temperature field was calculated and its variable law was analyzed by using the 3-D transient non-liner finite element method. The factors such as the solid-state phase change and the physical parameters with change of the temperature were considered, and the numerical results were coincident with the experimental data. The results show that the velocities of temperature changing at different positions of the rail's cross-section are different in the cooling progress, and the phase change and the irregular cross-section of rail are important influencing factors. [ABSTRACT FROM AUTHOR]

TheMHCclass I Ag presentation pathway in melanoma cells has a well-established role in immune-mediated destruction of tumors. However, the clinical significance of theMHCclass II Ag presentation pathway in melanoma cells is less clear. In Ag-presenting cells, IFN-γ-inducible lysosomal thiol reductase (GILT) is critical for MHC class II-restricted presentation of multiple melanoma Ags. Although not expressed in benign melanocytes of nevi, GILT and MHC class II expression is induced in malignant melanocytes in a portion of melanoma specimens. Analysis of The Cancer Genome Atlas cutaneous melanoma data set showed that high GILT mRNA expression was associated with improved overall survival. Expression of IFN-γ, TNF-α, and IL-1β was positively associated with GILT expression in melanoma specimens. These cytokines were capable of inducing GILT expression in human melanoma cells in vitro. GILT protein expression in melanocytes was induced in halo nevi, which are nevi undergoing immune-mediated regression, and is consistent with the association of GILT expression with improved survival in melanoma. To explore potential mechanisms of GILT's association with patient outcome, we investigated pathways related to GILT function and expression. In contrast to healthy skin specimens, in which the MHC class II pathway was nearly uniformly expressed and intact, there was substantial variation in the MHC class II pathway in the The Cancer Genome Atlas melanoma specimens. Both an active and intact MHC class II pathway were associated with improved overall survival in melanoma. These studies support a role for GILT and the MHC class II Ag presentation pathway in melanoma outcome. [ABSTRACT FROM AUTHOR]

Due to its excellent properties such as ultraviolet obscuration, chemical stability and small particle size, nano-titanium dioxide (nano-TiO2) is widely used, particularly in sunblock products. The skin is therefore a chief route for exposure. Studies have found that oral or respiratory exposure to nano-TiO2 has an adverse impact on the cardiovascular system. The relationship between dermal exposure to nano-TiO2 and cardiovascular system toxicity, particularly the causative mechanisms, remain unclear. In this study, we used Balb/c mice to evaluate cardiovascular toxicity from nano-TiO2 dermal exposure, and the underlying mechanisms associated with the human umbilical vein endothelial cells (HUVECs) were explored. Our results showed that nano-TiO2 treatment resulted in an obvious increase in reactive oxygen species and 8-hydroxy-2'-deoxyguanosine, indicating the appearance of oxidative stress. Moreover, the levels of inflammatory biomarkers, such as immunoglobulin E, soluble intercellular adhesion molecule-1, interleukin-8, and hypersensitive C-reactive protein, also increased. Exposing HUVECs to nano-TiO2 led to a decline in cell vitality, and an increase in caspase-3 levels, suggesting that nano-TiO2 exposure caused cytotoxicity and even cell apoptosis. Interestingly, neutralizing oxidative stress by administering Vitamin E was shown to reduce the inflammatory response and cytotoxicity. Our findings suggest that nano- TiO2 can injure the cardiovascular system via dermal exposure, and does this via oxidative stress-induced inflammation and cytotoxicity. Vitamin E treatment may be a strategy to mitigate the damage. [ABSTRACT FROM AUTHOR]