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91.
Evidence from clinical and epidemiological studies indicates that women are disproportionately susceptible to sexually transmitted viral infections. To understand the underlying biological basis for this increased susceptibility, more studies are needed to examine the acute events in the female reproductive tract following exposure to viruses during sexual transmission. The epithelial lining of the female reproductive tract is the primary barrier that sexually transmitted viruses, such as HIV-1 and HSV-2 need to infect or traverse, in order to initiate and establish productive infection. We have established an ex-vivo primary culture system to grow genital epithelial cells from upper reproductive tract tissues of women. Using these cultures, we have extensively examined the interactions between epithelial cells of the female genital tract and HSV-2 and HIV-1. In this review, we describe in detail the experimental protocol to grow these cultures, monitor their differentiation and inoculate with HSV-2 and HIV-1. Prospective use of these cultures to re-create the microenvironment in the reproductive tract is discussed. 相似文献
92.
In this study, our aim was to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the vitamin B12 therapy response in 95 patients with vitamin B12 deficiency and 92 healthy control subjects using vitamin B12, plasma total homocysteine (tHcy), and folate as the main measure of outcome. MTHFR C677T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism techniques. There were no differences in the distribution of MTHFR genotypes in the cases versus the controls. Mean concentrations of plasma tHcy and B12 vitamin were 18.84 μM and 142.47 pg/mL in patients with TT (10.5%) genotypes. Furthermore, mean concentrations of B12 vitamin after cobalamin therapy were 697.62, 656.64, and 488.76 pg/mL in patients with the CC, CT, and TT genotypes, respectively. The MTHFR 677 TT genotype has decreasing effect in B12 vitamin and increasing effect in tHcy. In comparison with the patients having CC and CT genotypes, patients with the TT genotype had a lower response to vitamin B12 therapy. 相似文献
93.
Demir D Gençer N Arslan O Genç H Zengin M 《Journal of enzyme inhibition and medicinal chemistry》2012,27(1):125-131
A new series of N,N'-diarylureas (1-9) was synthesized. These compounds were investigated as inhibitors of polyphenol oxidase (PPO) which had been purified from banana by an affinity gel comprised of Sepharose 4B-l-tyrosine-p-amino benzoic acid. K(i) values for (1), (2), (3), (5), (6), (7) and (8) were determined as 0.285, 17.97, 0.187, 0.108, 0.063, 0.044 and 0.047?mM, respectively. Thus (2) was by far the most effective inhibitor. Interestingly, (4) and (9) behaved as an activator of PPO in this study. 相似文献
94.
95.
The NKG2D receptor costimulates effector/memory CD8 T cells and is normally absent on CD4 T cells but can be induced by T cell antigen receptor complex stimulation and interleukin-15 (IL-15). Among its ligands are the human major histocompatibility complex class I-related MICA and MICB, which have a restricted tissue distribution but are frequently associated with malignancies and some microbial infections. Moreover, aberrant expression of MIC may promote autoimmune disease progression. Human T cell lymphotropic virus type I (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic inflammatory disease of the central nervous system that resembles multiple sclerosis. Disease progression involves production of IL-15 and its receptor through transactivation by the viral Tax regulator protein, an activated immune response state, and local cytokine production and T cell fratricide by Tax-specific cytotoxic T lymphocytes (CTL). This study shows that as with CD8 T cells, substantial proportions of HAM/TSP patient CD4 T cells are positive for NKG2D and that large numbers of T cells from both subsets express MIC, which can be transactivated by Tax independent of nuclear factor κB. Engagement of MIC by NKG2D promotes spontaneous HAM/TSP T cell proliferation and, apparently, CTL activities against HTLV-1-infected T cells. These results reveal a viral strategy that may exploit immune stimulatory mechanisms to negotiate a balance between promotion and limitation of infected host T cell expansions. 相似文献
96.
Hüseyin Çavdar Oktay Talaz Deniz Ekinci 《Bioorganic & medicinal chemistry letters》2012,22(24):7499-7503
Here we synthesized four novel indole conduritol derivatives 1–4 for the first time in the literature and probed their biological activities with the α and β-glucosidases. The compounds showed quite effective glucosidase inhibitory action. IC50 values of the compounds were compared with the known glucosidase inhibitor acarbose and it was determined that newly synthesized indole conduritols had more powerful effect against β-glucosidase in addition to exhibiting moderate influence against α-glucosidase. Our molecules thus constitute an important starting point for the design and exploitation of novel glucosidase inhibitors since glucosidase inhibitors have widespread applications in the treatment of diabetes, viral infections, lysosomal storage diseases and cancers. 相似文献
97.
Erikas Lutovinovas Hans-Peter Tschorsnig Miroslav Barták Oktay Dursun Hasan-Sungur Civelek 《法国昆虫学会纪事》2018,54(4):335-366
Faunistic records for 139 tachinid species from southwestern Turkey (Mu?la province and adjacent Ayd?n, Burdur, Denizli and Antalya provinces) are given. Another 17 species of the study area are known only from published records. The known fauna of Tachinidae of southwestern Turkey thus comprises 156 species. Zoogeographic analysis of the study area revealed that tachinids belong to 29 chorological categories, divided into two supergroups: 122 species (78.2%) are more eurybiontic, and also distributed in northern parts of the Palaearctic region (19 chorological categories belong here), whereas 34 species (21.8%) are distinctly thermophilic, and have a southern type of distribution (10 chorological categories are distinguished). Altogether, 52 species (33.3%) are recorded for the first time from Turkey. 相似文献
98.
The absorption spectra of N-acetyl-l-tryptophanamide in various solvents were resolved into the sums of the 1La and 1Lb components. The relative intensities of the 0-0 transitions of the 1Lb bands correlate linearly with the solvent polarity values (). A novel strategy that uses a set of the experimental 1Lb bands was employed to resolve the near-UV circular dichroism (CD) spectra of tryptophanyl residues. Resolved spectral parameters from the single-tryptophan mutants of tear lipocalin (TL), F99W and Y87W, corroborate the fluorescence and structural data of TL. Analysis of the 1Lb bands of the Trp CD spectra in proteins is a valuable tool to obtain the local features. The dimethyl sulfoxide (DMSO)-like 1Lb band of Trp CD spectra may be used as a “fingerprint” to identify the tryptophanyl side chains in situations where the benzene rings of Trp have van der Waals interactions with the side chains of its nearest neighbor. In addition, the signs and intensities of the components hold information about the side chain conformations and dynamics in proteins. Combined with Trp mutagenesis, this method, which we call site-directed circular dichroism, is broadly applicable to various proteins to obtain the position-specific data. 相似文献
99.
Barlow CA Kitiphongspattana K Siddiqui N Roe MW Mossman BT Lounsbury KM 《Apoptosis : an international journal on programmed cell death》2008,13(5):681-692
Oxidant stress plays a role in the pathogenesis of pulmonary diseases, including fibrotic lung disease and cancer. We previously
found that hydrogen peroxide (H2O2) initiates an increase in Ca2+/cAMP-response element binding protein (CREB) phosphorylation in C10 alveolar type II cells that requires activation of extracellular
regulated kinases 1/2 (ERK1/2). Here, we investigated the role of crosstalk between protein kinase A (PKA) and epidermal growth
factor receptor (EGFR) in oxidant-induced signaling to ERK1/2 and CREB in C10 cells. Application of H2O2 increased nuclear accumulation of PKA, and inhibition of PKA with H89 reduced oxidant-mediated phosphorylation of both CREB
and ERK1/2. Single cell measurements of cAMP and redox status, using a FRET-based biosensor and a redox-sensitive GFP, respectively,
indicated that H2O2 increases production of cAMP that correlates with redox state. Inhibition of EGFR activity decreased both H2O2-induced CREB phosphorylation and translocation of PKA to the nucleus, suggesting that crosstalk between PKA and EGFR underlies
the oxidant-induced CREB response. Furthermore, knockdown of CREB expression using siRNA led to a decrease in bcl-2 and an
increase in oxidant-induced apoptosis. Together these data reveal a novel role for crosstalk between PKA, ERK1/2 and CREB
that mediates cell survival during oxidant stress. 相似文献
100.