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181.
Despite of encountering a robust immune response, Mycobacterium tuberculosis (MTB) successfully survives and persists in the human host. We investigated the early regulation of MTB 85B gene by allicin in MTB-infected human monocytes. During the first 24h of infection, levels of both MTB 85B intracellular mRNA and secreted protein were significantly down-regulated by allicin in a dose-dependent manner, which was mediated by inhibition of glutathione and NF-kappaB pathway. Allicin-induced MTB 85B suppression correlated with suppression of TNF-alpha released from infected monocytes. The allicin-induced up-regulation of glutathione and IFN-gamma with simultaneous decrease in TNF-alpha supports the anti-inflammatory property of allicin by elicitation of protective immune response. Thus, allicin may prove to be valuable in the containment of MTB and therefore be useful as an adjunct in treatment of tuberculosis.  相似文献   
182.
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease due to ECGF1 gene mutations causing thymidine phosphorylase (TP) deficiency. Analysis of post-mortem samples of five MNGIE patients and two controls, revealed TP activity in all control tissues, but not in MNGIE samples. Converse to TP activity, thymidine and deoxyuridine were absent in control samples, but present in all tissues of MNGIE patients. Concentrations of both nucleosides in the tissues were generally higher than those observed in plasma of MNGIE patients. Our observations indicate that in the absence of TP activity, tissues accumulate nucleosides, which are excreted into plasma.  相似文献   
183.
184.
Cervical cancer is among the most common type of cancers in women and is associated with human papillomavirus (HPV) infection. Genital warts are also reported to be linked with HPV infection types 11 and 6. In turn, clinical characteristics and morphological features of warts may be useful in the prediction of prognosis and in making treatment decisions. Thus, we have investigated the association of high and low-risk HPVs genotype with genital wart risk, as well as pathological and cytological information in cases recruited from a population-based cohort study of 1380 patients. Patients infected with HPV genotype 6 or 11 had an increased risk of having warts, with OR of 2.34 (95% CI: 0.955-5.737, P = 0.06). Also, this association was enhanced in the presence of high plus low-risk HPV for having genital wart (OR: 2.814; 95%: 1.208-6.55, P = 0.017) and cases having high-risk HPV (OR: 2.329; 95% CI: 1.029-5.269, P = 0.042). Moreover, we observed patients with genital warts having CIN2/3, indicating the importance of informing the physician to the patient to prevent more severe lesions. Our data demonstrated that patients with both low/high-risk HPV types had an increased risk of developing genital warts and persistent infection with HPV was a necessary precursor for the increase in cervical lesions.  相似文献   
185.
Miri  Saba  Hajihosseini  Reza  Saedi  Hamed  Vaseghi  Maryam  Rasooli  Azadeh 《Annals of microbiology》2019,69(13):1507-1515
Context

Fermented soybean products have been used in various ways, and more research is being conducted on them to reveal their benefit.

Objective

The objective of this study was to evaluate the antioxidative activity of fermented soybean meal extract by Lactobacillus plantarum in vitro and in vivo tests.

Materials and methods

A Lactobacillus plantarum strain RM10 was selected through plate and fermentation experiment, which increased the degree of protein hydrolysis (1.015 μg/mL) and antioxidant activity in soybean meal fermented by selected bacteria (FSBM). In vivo study was done on septic rats as an inflammation/infection model, and then the trial groups were treated with different concentrations of fermented soybean meal extracts (FSBM, 5, 10, and 20%).

Results

DPPH radical-scavenging and ferrozine ion-chelating activity enhanced (P < 0.05) after fermentation of soybean meal compared to control group. Reduced (P < 0.05) expression of inflammatory genes and enzymes was detected in the lungs of rats treated with fermented soybean meal extract.

Discussion and conclusions

These results demonstrated that a diet containing fermented soybean meal extract improved extreme inflammatory response in an infectious disease like sepsis by reducing inflammatory factors.

  相似文献   
186.
The interaction of SnMe2Cl2(bu2bpy)complex with calf thymus DNA (ct-DNA) has been explored following, using spectroscopic methods, viscosity measurements, Atomic force microscopy, Thermal denaturation and Molecular docking. It was found that Sn(IV) complex could bind with DNA via intercalation mode as evidenced by hyperchromism and bathochromic in UV–Vis spectrum; these spectral characteristics suggest that the Sn(IV) complex interacts with DNA most likely through a mode that involves a stacking interaction between the aromatic chromophore and the base pairs of DNA. In addition, the fluorescence emission spectra of intercalated methylene blue (MB) with increasing concentrations of SnMe2Cl2(bu2bpy) represented a significant increase of MB intensity as to release MB from MB-DNA system. Positive values of ΔH and ΔS imply that the complex is bound to ct-DNA mainly via the hydrophobic attraction. Large complexes contain the DNA chains with an average size of 859?nm were observed by using AFM for Sn(IV) Complex–DNA. The Fourier transform infrared study showed a major interaction of Sn(IV) complex with G-C and A-T base pairs and a minor perturbation of the backbone PO2 group. Addition of the Sn(IV)complex results in a noticeable rise in the Tm of DNA. In addition, the results of viscosity measurements suggest that SnMe2Cl2(bu2bpy) complex may bind with the classical intercalative mode. From spectroscopic and hydrodynamic studies, it has been found that Sn(IV)complex interacts with DNA by intercalation mode. Optimized docked model of DNA–complex mixture confirmed the experimental results.  相似文献   
187.
188.
Germ cell sex is defined by factors derived from somatic cells. CYP26B1 is known to be a male sex-promoting factor that inactivates retinoic acid (RA) in somatic cells. In CYP26B1-null XY gonads, germ cells are exposed to a higher level of RA than in normal XY gonads and this activates Stra8 to induce meiosis while male-specific gene expression is suppressed. However, it is unknown whether meiotic entry by an elevated level of RA is responsible for the suppression of male-type gene expression. To address this question, we have generated Cyp26b1/Stra8 double knockout (dKO) embryos. We successfully suppressed the induction of meiosis in CYP26B1-null XY germ cells by removing the Stra8 gene. Concomitantly, we found that the male genetic program represented by the expression of NANOS2 and DNMT3L was totally rescued in about half of dKO germ cells, indicating that meiotic entry causes the suppression of male differentiation. However, half of the germ cells still failed to enter the appropriate male pathway in the dKO condition. Using microarray analyses together with immunohistochemistry, we found that KIT expression was accompanied by mitotic activation, but was canceled by inhibition of the RA signaling pathway. Taken together, we conclude that inhibition of RA is one of the essential factors to promote male germ cell differentiation, and that CYP26B1 suppresses two distinct genetic programs induced by RA: a Stra8-dependent meiotic pathway, and a Stra8-independent mitotic pathway.  相似文献   
189.
NANOS2 is an RNA-binding protein essential for fetal male germ cell development. While we have shown that the function of NANOS2 is vital for suppressing meiosis in embryonic XY germ cells, it is still unknown whether NANOS2 plays other roles in the sexual differentiation of male germ cells. In this study, we addressed the issue by generating Nanos2/Stra8 double knockout (dKO) mice, whereby meiosis was prohibited in the double-mutant male germ cells. We found that the expression of male-specific genes, which was decreased in the Nanos2 mutant, was hardly recovered in the dKO embryo, suggesting that NANOS2 plays a role in male gene expression other than suppression of meiosis. To investigate the molecular events that may be controlled by NANOS2, we conducted a series of microarray analyses to search putative targets of NANOS2 that fulfilled 2 criteria: (1) increased expression in the Nanos2 mutant and (2) the mRNA associated with NANOS2. Interestingly, the genes predominantly expressed in undifferentiated primordial germ cells (PGCs) were significantly selected, implying the involvement of NANOS2 in the termination of the characteristics of PGCs. Furthermore, we showed that NANOS2 is required for the maintenance of mitotic quiescence, but not for the initiation of the quiescence in fetal male germ cells. These results suggest that NANOS2 is not merely a suppressor of meiosis, but instead plays pivotal roles in the sexual differentiation of male germ cells.  相似文献   
190.
Unlike the other MAP3Ks, MEKK1 (encoded by Map3k1) contains a PHD motif. To understand the role of this motif, we have created a knockin mutant of mouse Map3k1 (Map3k1mPHD) with an inactive PHD motif. Map3k1mPHD ES cells demonstrate that the MEKK1 PHD controls p38 and JNK activation during TGF‐β, EGF and microtubule disruption signalling, but does not affect MAPK responses to hyperosmotic stress. Protein microarray profiling identified the adaptor TAB1 as a PHD substrate, and TGF‐β‐ or EGF‐stimulated Map3k1mPHD ES cells exhibit defective non‐canonical ubiquitination of MEKK1 and TAB1. The MEKK1 PHD binds and mediates the transfer of Lys63‐linked poly‐Ub, using the conjugating enzyme UBE2N, onto TAB1 to regulate TAK1 and MAPK activation by TGF‐β and EGF. Both the MEKK1 PHD and TAB1 are critical for ES‐cell differentiation and tumourigenesis. Map3k1mPHD/+ mice exhibit aberrant cardiac tissue, B‐cell development, testis and T‐cell signalling.  相似文献   
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