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991.
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993.
Women constitute more than 50% out of millions of individuals infected with HIV-1, the major causative agent of acquired immune deficiency syndrome. About 40% of HIV-1 infections have been reported to initiate in the female reproductive tract. However, the mechanisms through which these infections are spread are poorly understood; hence, there is now a major concern in women who use long acting injectable hormonal contraceptives, particularly Depo-Provera and an increase of HIV-1 risk acquisition. Based on literature, Depo-Provera has an affinity for both the glucocorticoid receptor and the progesterone receptor in the female reproductive tract. Therefore, investigating HIV-1 pathogenesis in the female reproductive tract via the glucocorticoid receptor and the progesterone receptor mechanisms in response to the effect of Depo-Provera is of great importance.  相似文献   
994.
Tolnaftate is a thiocarbamate antifungal drug which is therapeutically active against dermatophytes that cause various forms of tinea. Due to the small amount of tolnaftate released from ordinary ointment bases and insufficient penetration through the infected skin layers the need to incorporate the drug in a more suitable pharmaceutical form has evolved. A provesicular system is one such form that can solve these problems. Once in contact with the skin, dilution with moisture occurs and the provesicular system rapidly transforms into a vesicular one. Provesicular systems were prepared according to full-factorial experimental design. Plain provesicular systems were compared with systems containing Phospholipon 80?H and Lipoid S45 as penetration enhancers. Design expert software was used to analyze the effect of formulation variables (type of Span used as well as the presence or the absence of the penetration enhancer and its type) on the dependent variables: percent encapsulation efficiency (EE%), vesicle size and percent in vitro drug released). Three formulations were chosen; a plain provesicular system (PV-2), one containing Phospholipon 80H (PV-6) and another containing Lipoid S45 (PV-10) with the goal to reveal the effect of penetration enhancer on morphology, rheological properties and ex vivo permeation using confocal laser scanning microscopy (CLSM). Analysis of CLSM results showed that the penetration enhancing effect for the tested formulations followed the order PV-10?>?PV-6?>?PV-2. Promising clinically active treatment for tinea patients could be expected as shown by the in vivo permeation results for the provesicular systems as suggested by the CLSM results.  相似文献   
995.
Ideal coatings for orthopedic implants should be able to induce excellent osseointegration with host bone tissue, which requires good osteogenic responses and limited inflammatory reactions. Cerium oxide (CeO2) ceramics have anti-oxidative properties and can be used to decrease mediators of inflammation, making them attractive for biomedical application. In this study, two kinds of CeO2 incorporated calcium silicate coatings (CS-10Ce and CS-30Ce) were prepared via plasma spraying technique, and the effects of CeO2 addition on the responses of bone mesenchymal stem cells (BMSCs) and RAW264.7 macrophages were evaluated. The CS-10Ce and CS-30Ce coatings were characterized by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. An increase in CeO2 content in the coatings resulted in enhanced chemical stability and better BMSCs osteogenic behaviors in terms of cell adhesion, proliferation, ALP activity, and mineralized nodule formation. With respect to either ZrO2-added or unmodified CS coating, the CS-30Ce coating elicited higher effects on the macrophages, suppressing the gene expressions of pro-inflammatory (M1) markers (CCR7, IL-6, and TNF-α), while upregulating the expressions of anti-inflammatory (M2) markers (CD206, IL-1ra, and IL-10); moreover, it could also increase the expression of osteoinductive molecules (BMP2 and TGF-β1) by the macrophages. The results suggested that the regulation of BMSCs behaviors and macrophage-mediated responses at the coating’s surface was related to CeO2 incorporation. The incorporation of CeO2 in CS coatings can be a valuable strategy to promote osteogenic responses and mitigate inflammatory reactions.  相似文献   
996.
Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by abnormal autoreactivity in B cells. Lymphocytes and their soluble mediators contribute to the disease pathogenesis. We recently demonstrated that infecting lupus mice with malaria confers protection against lupus nephritis by attenuating oxidative stress in both liver and kidney tissues. In the current study, we further investigated B cell autoreactivity in female BWF1 lupus mice after infection with either live or gamma-irradiated malaria, using ELISA, flow cytometry and Western blot analysis. The lupus mice exhibited a significant elevation in plasma levels of IL-4, IL-6, IL-7, IL-12, IL-17, IFN-α, IFN-γ, TGF-β, BAFF and APRIL and a marked elevation of IgG2a, IgG3 and ant-dsDNA autoantibodies compared with normal healthy mice. Infecting lupus mice with live but not gamma-irradiated malaria parasite partially and significantly restored the levels of the soluble mediators that contribute to the progression of lupus. Furthermore, the B cells of lupus mice exhibited an increased proliferative capacity; aberrant overexpression of the chemokine receptor CXCR4; and a marked elevation in responsiveness to their cognate ligand (CXCL12) via aberrant activation of the PI3K/AKT, NFκB and ERK signaling pathways. Interestingly, infecting lupus mice with live but not gamma-irradiated malaria parasite restored a normal proliferative capacity, surface expression of CXCR4 and B cell response to CXCL-12. Taken together, our data present interesting findings that clarify, for the first time, the molecular mechanisms of how infection of lupus mice with malaria parasite controls B cell autoreactivity and thus confers protection against lupus severity.  相似文献   
997.
An efficient protocol for the regeneration of lavandin (Lavandula x intermedia cv. 'Grosso') is reported. Thiadazuron (9 μM), a plant growth-modulating phenylurea, was used to induce callus formation and shoot initiation from cultured leaf explants. Newly emerged shoots were maintained on media containing 0.05 μM naphthaleneacetic acid to allow maturation, and then transferred to media containing 2.9 μM indole-3-acetic acid to allow root formation. The phenolic control agents polyvinylpyrrolidone (PVP), ascorbic acid, 2-aminoindane-2-phosphonic acid, and activated charcoal were tested for their ability to prevent shoot browning and death in culture. All agents except PVP were found to be effective, with ascorbic acid being most consistent in promoting development of healthy mature shoots. The effect of light type (red light vs. white light) and culture medium composition (full- and half-strength Murashige and Skoog or Llyod and McCown’s woody plant medium (WPM)) on rooting efficiency was also evaluated. Cultures on half-strength WPM in white light were found to have the highest rooting efficiency. Additionally, application of the polyamines putrescine, spermine, and spermidine were tested for their effect on rooting. While rooting efficiency was not improved with any of the treatments, spermine and spermidine were found to have an inhibitory effect at concentrations greater than 10 μM.  相似文献   
998.
The present study involves red palm weevil adults Rhynchophorus ferrugineus (Oliver) (Coleoptera: Curculionidae) irradiated with 5, 10 or 15 Gy of gamma radiation. The biological effects of gamma irradiation on the F1 adult females, descendant of irradiated parental male pupae, were studied. The percentage egg hatch decreased significantly, as the dose increased, compared with the untreated control.The effect of gamma irradiation on the morphology of the ovaries showed a remarkable effect on size, shape and measurement of the paired ovaries.Additionally, histological studies showed some damages by irradiation of the oocytes maturation, which increased with increasing dose. These symptoms were elongation of the terminal filament, rupture, separation, or shrinkage of external sheath and follicular epithelium, degenerated or absent of nurse cells, and ruptured oocytes at 15 Gy.Vacuolation appeared in different degrees inside the oocytes and the nurse cells were absent in some areas. The damage in the oocytes was more severe as the dose was increased. The follicular epithelium was thin, oocytes clumped together throughout the ovariole causing some oocytes become abnormal or rectangular in shape.  相似文献   
999.
A 16S rRNA-targeted, Cy3-labeled oligonucleotide probe was designed to detect members of the genus Bdellovibrio by fluorescence in situ hybridization. Specific hybridization conditions were established; however, the detection of bdellovibrios in environmental samples required enrichment, confirming that Bdellovibrio spp. are not present in large numbers in the environment.  相似文献   
1000.
Current Fungal Infection Reports - Until recently, the human microbiome was synonymous with the bacterial community. Fortunately, recent studies have shown that the human microbiome is complex and...  相似文献   
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