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11.
An epidemiological study of Ehrlichia canis infection in dogs in Peninsular Malaysia was carried out using molecular detection techniques. A total of 500 canine blood samples were collected from veterinary clinics and dog shelters. Molecular screening by polymerase chain reaction (PCR) was performed using genus-specific primers followed by PCR using E. canis species-specific primers. Ten out of 500 dogs were positive for E. canis. A phylogenetic analysis of the E. canis Malaysia strain showed that it was grouped tightly with other E. canis strains from different geographic regions. The present study revealed for the first time, the presence of genetically confirmed E. canis with a prevalence rate of 2.0% in naturally infected dogs in Malaysia.  相似文献   
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The vacuole is the most prominent organelle of plant cells. Despite its importance for many physiological and developmental aspects of plant life, little is known about its biogenesis and maintenance. Here we show that Arabidopsis plants expressing a dominant‐negative version of the AAA (ATPase associated with various cellular activities) ATPase AtSKD1 (SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1) under the control of the trichome‐specific GLABRA2 (GL2) promoter exhibit normal vacuolar development in early stages of trichome development. Shortly after its formation, however, the large central vacuole is fragmented and finally disappears completely. Secretion assays with amylase fused to the vacuolar sorting signal of Sporamin show that dominant‐negative AtSKD1 inhibits vacuolar trafficking of the reporter that is instead secreted. In addition, trichomes expressing dominant‐negative AtSKD1 frequently contain multiple nuclei. Our results suggest that AtSKD1 contributes to vacuolar protein trafficking and thereby to the maintenance of the large central vacuole of plant cells, and might play a role in cell‐cycle regulation.  相似文献   
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International Journal of Peptide Research and Therapeutics - Infections with HCV, HBV and poliovirus are still considered to be substantial global health burdens. Vaccination is one of the most...  相似文献   
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Proper T cell function relies on the integration of signals delivered by Ag, cytokine, and costimulatory receptors. In this study, the interactions between IL-2, CD27, and its ligand CD70 and their effects on human T cell function were examined. Unstimulated CD8(+) T cells expressed relatively low levels of CD70 and high levels of CD27. Incubation in vitro with high doses of IL-2 (3,000 IU/ml) or administration of IL-2 in vivo resulted in substantial up-regulation of CD70 expression and the concomitant loss of cell surface CD27 expression on CD8(+) cells. Withdrawal of IL-2 from activated CD8(+) T cells that had been maintained in IL-2 resulted in a reversal of the expression of these two markers, whereas reciprocal changes were seen following treatment of PBMCs with IL-2. The proliferation observed in cells stimulated with IL-2 primarily occurred in a subset of the CD70(+)CD8(+) T cells that up-regulated IL-2 receptor expression but did not occur in CD70(-)CD8(+) T cells. Blocking CD70 resulted in a significant reduction of T cell proliferation induced by high-dose IL-2, indicating that the interaction of CD70 with CD27 played a direct role in T cell activation mediated by IL-2. Finally, studies conducted on tumor-infiltrating lymphocyte (TIL) samples that were administered to melanoma patients indicated that the size of the pool of CD27(+)CD8(+) T cells in bulk TILs was highly associated (p = 0.004) with the ability of these TILs to mediate tumor regression following adoptive transfer.  相似文献   
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Development and activation of B cells quickly became clear after identifying new ligands and receptors in the tumor necrosis factor superfamily. B cell–activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are the members of membrane proteins Type 2 family released by proteolytic cleavage of furin to form active, soluble homotrimers. Except for B cells, ligands are expressed by all such immune cells like T cells, dendritic cells, monocytes, and macrophages. BAFF and APRIL have two common receptors, namely TNFR homolog transmembrane activator and Ca2+ modulator and CAML interactor (TACI) and B cell–maturation antigen. BAFF alone can also be coupled with a third receptor called BAFFR (also called BR3 or BLyS Receptor). These receptors are often expressed by immune cells in the B-cell lineage. The binding of BAFF or APRIL to their receptors supports B cells differentiation and proliferation, immunoglobulin production and the upregulation of B cell–effector molecules expression. It is possible that the overexpression of BAFF and APRIL contributes to the pathogenesis of autoimmune diseases. In BAFF transgenic mice, there is a pseudo-autoimmune manifestation, which is associated with an increase in B-lymphocytes, hyperglobulinemia, anti-single stranded DNA, and anti-double-stranded DNA antibodies, and immune complexes in their peripheral blood. Furthermore, overexpressing BAFF augments the number of peripheral B220+ B cells with a normal proliferation rate, high levels of Bcl2, and prolonged survival and hyperactivity. Therefore, in this review article, we studied BAFF and APRIL as important mediators in B-cell and discussed their role in rheumatoid arthritis.  相似文献   
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The amino acid l-alpha-alanine has attracted considerable interest for use in radiation dosimetry and has been formally accepted as a secondary standard for high-dose and transfer dosimetry. Recent results have shown that the alanine EPR spectrum consists of contributions from three different radicals. A set of benchmark spectra describing the essential spectral features of these three radical components was used for reconstructions of the experimental spectra. In the present work, these basis spectra have been used to investigate the differential effects of variations in radiation doses and microwave power, as well as the dependence upon temperature annealing and UV illumination. The results presented here, based solely on relatively low-energy (60-80 keV) X rays, indicate that the three components behave very similarly with respect to radiation dose at room temperature. However, with respect to the thermal annealing/fading behavior and microwave power saturation properties, the three species behave significantly differently. It is concluded that even if it is now realized that three different radicals contribute to the composite EPR alanine spectrum, this has a minor impact on the established protocols for present-day applications (high-dose) of EPR/alanine dosimetry. However, some care should be exercised when e.g. constructing calibration curves, since fading and power saturation behavior may vary over the dose range in question. New results from UV-illumination experiments suggest a possible procedure for experimental spectral separation of the EPR signals due to the three radicals.  相似文献   
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Iodine deficiency has been shown to have high prevalence in Iran despite sufficient iodine supplementation. Zinc deficiency may also contribute to the pathogenesis of endemic goiter. The aim of this study was to compare serum zinc level in Iranian school children with and without goiter. A cross-sectional study was performed among urban children aged 8-12 years in city of Kerman, Iran. A multistage proportional to size cluster sampling method was used to screen 5500 subjects out of 29,787 students. After the screening phase, serum and urine specimens of randomly selected 165 students were evaluated for serum zinc levels and urinary iodine excretion and compared in goiterous and non-goiterous children. Serum zinc level was 149.5±29.4 μg/l in goiterous children and 141.2±52 μg/l in non-goiterous children but no significant difference was found between the groups (p=0.37). But urinary iodine excretion was significantly (p<0.001) lower in goiterous children (207.5 μg/l in goiterous children and 262.5 μg/l in non-goiterous children). This study showed that serum zinc level in goiterous and non-goiterus children is not different and zinc deficiency is not a risk factor for endemic goiter in this population.  相似文献   
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