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Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 106 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to be more beneficial for treating breast cancer than donkey milk.  相似文献   
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Despite tremendous advances in our understanding of HIV/AIDS since the first cases were reported 30 years ago, we are still a long way from understanding critical steps of HIV acquisition, pathogenesis and correlates of protection. Our new understanding of the importance of the mucosa as a target for HIV infection, as well as our recent observations showing that altered expression and responses of innate pattern recognition receptors are significantly associated with pathogenesis and resistance to HIV infection, indicate that correlates of immunity to HIV are more likely to be associated with mucosal and innate responses. Most of the heterosexual encounters do not result in productive HIV infection, suggesting that the female genital tract is protected against HIV by innate defence molecules, such as antiproteases, secreted mucosally. The present review highlights the role and significance of the serine protease inhibitors SLPI (secretory leucocyte protease inhibitor), trappin-2, elafin and ps20 (prostate stromal protein 20 kDa) in HIV susceptibility and infection. Interestingly, in contrast with SLPI, trappin-2 and elafin, ps20 has been shown to enhance HIV infectivity. Thus understanding the balance and interaction of these factors in mucosal fluids may significantly influence HIV infection.  相似文献   
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Cervicovaginal lavage fluid (CVL) is a natural source of anti-HIV-1 factors; however, molecular characterization of the anti-HIV-1 activity of CVL remains elusive. In this study, we confirmed that CVLs from HIV-1-resistant (HIV-R) compared to HIV-1-susceptible (HIV-S) commercial sex workers (CSWs) contain significantly larger amounts of serine antiprotease trappin-2 (Tr) and its processed form, elafin (E). We assessed anti-HIV-1 activity of CVLs of CSWs and recombinant E and Tr on genital epithelial cells (ECs) that possess (TZM-bl) or lack (HEC-1A) canonical HIV-1 receptors. Our results showed that immunodepletion of 30% of Tr/E from CVL accounted for up to 60% of total anti-HIV-1 activity of CVL. Knockdown of endogenous Tr/E in HEC-1A cells resulted in significantly increased shedding of infectious R5 and X4 HIV-1. Pretreatment of R5, but not X4 HIV-1, with either Tr or E led to inhibition of HIV-1 infection of TZM-bl cells. Interestingly, when either HIV-1 or cells lacking canonical HIV-1 receptors were pretreated with Tr or E, HIV-1 attachment and transcytosis were significantly reduced, and decreased attachment was not associated with altered expression of syndecan-1 or CXCR4. Determination of 50% inhibitory concentrations (IC(50)) of Tr and E anti-HIV-1 activity indicated that E is ~130 times more potent than its precursor, Tr, despite their equipotent antiprotease activities. This study provides the first experimental evidence that (i) Tr and E are among the principal anti-HIV-1 molecules of CVL; (ii) Tr and E affect cell attachment and transcytosis of HIV-1; (iii) E is more efficient than Tr regarding anti-HIV-1 activity; and (iv) the anti-HIV-1 effect of Tr and E is contextual.  相似文献   
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We present an updated account of breast cancer treatment and of progress toward “precision” cancer therapy; we focus on new developments in diagnostic molecular pathology and breast cancer that have emerged during the past 2 years. Increasing awareness of new prognostic and predictive methodologies, and introduction of next generation sequencing has increased understanding of both tumor biology and clinical behavior, which offers the possibility of more appropriate therapeutic choices. It remains unclear which of these testing methodologies provides the most informative and cost-effective actionable results for predictive and prognostic pathology. It is likely, however, that an integrated “step-wise” approach that uses the traditional clinical-pathologic paradigms coordinated with molecular characterization of breast tumor tissue, will offer the most comprehensive and cost-effective options for individualized, “precision” therapy for patients with breast cancer.  相似文献   
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Background  

Protein structures have conserved features – motifs, which have a sufficient influence on the protein function. These motifs can be found in sequence as well as in 3D space. Understanding of these fragments is essential for 3D structure prediction, modelling and drug-design. The Protein Data Bank (PDB) is the source of this information however present search tools have limited 3D options to integrate protein sequence with its 3D structure.  相似文献   
38.

Background  

Paracoccidioides brasiliensis is a dimorphic fungus that causes the most prevalent systemic mycosis in Latin America. The response to heat shock is involved in pathogenesis, as this pathogen switches from mycelium to yeast forms in a temperature dependent fashion that is essential to establish infection. HSP90 is a molecular chaperone that helps in the folding and stabilization of selected polypeptides. HSP90 family members have been shown to present important roles in fungi, especially in the pathogenic species, as an immunodominant antigen and also as a potential antifungal therapeutic target.  相似文献   
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Recombinant human parainfluenza virus type 1 (rHPIV1) was modified to create rHPIV1-P(C-), a virus in which expression of the C proteins (C', C, Y1, and Y2) was silenced without affecting the amino acid sequence of the P protein. Infectious rHPIV1-P(C-) was readily recovered from cDNA, indicating that the four C proteins were not essential for virus replication. Early during infection in vitro, rHPIV1-P(C-) replicated as efficiently as wild-type (wt) HPIV1, but its titer subsequently decreased coincident with the onset of an extensive cytopathic effect not observed with wt rHPIV1. rHPIV1-P(C-) infection, but not wt rHPIV1 infection, induced caspase 3 activation and nuclear fragmentation in LLC-MK2 cells, identifying the HPIV1 C proteins as inhibitors of apoptosis. In contrast to wt rHPIV1, rHPIV1-P(C-) and rHPIV1-C(F170S), a mutant encoding an F170S substitution in C, induced interferon (IFN) and did not inhibit IFN signaling in vitro. However, only rHPIV1-P(C-) induced apoptosis. Thus, the anti-IFN and antiapoptosis activities of HPIV1 were separable: both activities are disabled in rHPIV1-P(C-), whereas only the anti-IFN activity is disabled in rHPIV1-C(F170S). In African green monkeys (AGMs), rHPIV1-P(C-) was considerably more attenuated than rHPIV1-C(F170S), suggesting that disabling the anti-IFN and antiapoptotic activities of HPIV1 had additive effects on attenuation in vivo. Although rHPIV1-P(C-) protected against challenge with wt HPIV1, its highly restricted replication in AGMs and in primary human airway epithelial cell cultures suggests that it might be overattenuated for use as a vaccine. Thus, the C proteins of HPIV1 are nonessential but have anti-IFN and antiapoptosis activities required for virulence in primates.  相似文献   
40.
A recent workshop discusses the progress toward integrating NMR data into a unifying data model.  相似文献   
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