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21.
Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70 kDa heat shock protein (hsp70) and 60 kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois’ leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis.  相似文献   
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This work demonstrated the constitutive expressionof peroxisome proliferator-activated receptor (PPAR)- and PPAR-in rat synovial fibroblasts at both mRNA and protein levels. A decrease in PPAR- expression induced by 10 µg/ml lipopolysaccharide (LPS) was observed, whereas PPAR- mRNA expression was not modified. 15-Deoxy-12,14-prostaglandin J2(15d-PGJ2) dose-dependently decreased LPS-induced cyclooxygenase (COX)-2 (80%) and inducible nitric oxide synthase (iNOS) mRNA expression (80%), whereas troglitazone (10 µM) only inhibited iNOS mRNA expression (50%). 15d-PGJ2 decreasedLPS-induced interleukin (IL)-1 (25%) and tumor necrosis factor(TNF)- (40%) expression. Interestingly, troglitazone stronglydecreased TNF- expression (50%) but had no significant effect onIL-1 expression. 15d-PGJ2 was able to inhibitDNA-binding activity of both nuclear factor (NF)-B and AP-1.Troglitazone had no effect on NF-B activation and was shown toincrease LPS-induced AP-1 activation. 15d-PGJ2 andtroglitazone modulated the expression of LPS-induced iNOS, COX-2, andproinflammatory cytokines differently. Indeed, troglitazone seems tospecifically target TNF- and iNOS pathways. These results offer newinsights in regard to the anti-inflammatory potential of the PPAR-ligands and underline different mechanisms of action of15d-PGJ2 and troglitazone in synovial fibroblasts.

  相似文献   
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A large-scale study on canine Leishmania infection (CanL) was conducted in six localities along a west-east transect in the Algerian littoral zone (Tlemcen, Mostaganem, Tipaza, Boumerdes, Bejaia, Jijel) and covering two sampling periods. In total 2,184 dogs were tested with an indirect fluorescent antibody test (IFAT) and a direct agglutination test (DAT). Combined multiple-testing and several statistical methods were compared to estimate the CanL true prevalence and tests characteristics (sensitivity and specificity). The Bayesian full model showed the best fit and yielded prevalence estimates between 11% (Mostaganem, first period) and 38% (Bejaia, second period). Sensitivity of IFAT varied (in function of locality) between 86% and 88% while its specificity varied between 65% and 87%. DAT was less sensitive than IFAT but showed a higher specificity (between 80% and 95% in function of locality or/and season). A general increasing trend of the CanL prevalence was noted from west to east. A concordance between the present results and the incidence of human cases of visceral leishmaniasis was observed, where also a maximum was recorded for Bejaia. The results of the present study highlight the dangers when using IFAT as a gold standard.  相似文献   
24.
Synovial fibroblasts in persistent inflammatory arthritis have been suggested to have parallels with cancer growth and wound healing, both of which involve a stereotypical serum response programme. We tested the hypothesis that a serum response programme can be used to classify diseased tissues, and investigated the serum response programme in fibroblasts from multiple anatomical sites and two diseases. To test our hypothesis we utilized a bioinformatics approach to explore a publicly available microarray dataset including rheumatoid arthritis (RA), osteoarthritis (OA) and normal synovial tissue, then extended those findings in a new microarray dataset representing matched synovial, bone marrow and skin fibroblasts cultured from RA and OA patients undergoing arthroplasty. The classical fibroblast serum response programme discretely classified RA, OA and normal synovial tissues. Analysis of low and high serum treated fibroblast microarray data revealed a hierarchy of control, with anatomical site the most powerful classifier followed by response to serum and then disease. In contrast to skin and bone marrow fibroblasts, exposure of synovial fibroblasts to serum led to convergence of RA and OA expression profiles. Pathway analysis revealed three inter-linked gene networks characterising OA synovial fibroblasts: Cell remodelling through insulin-like growth factors, differentiation and angiogenesis through _3 integrin, and regulation of apoptosis through CD44. We have demonstrated that Fibroblast serum response signatures define disease at the tissue level, and that an OA specific, serum dependent repression of genes involved in cell adhesion, extracellular matrix remodelling and apoptosis is a critical discriminator between cultured OA and RA synovial fibroblasts.  相似文献   
25.
The free-living mite species Sancassania rodionovi (Zachvatkin) (Acari: Acaridae), is a serious pest of mushrooms in Iran. Studies were conducted to examine the development of this mite in relation to temperature on two mushroom species: Agaricus bisporus Lange (button mushroom) and Pleurotus ostreatus Kummer (oyster mushroom). The developmental time of this acarid mite was studied at eight constant temperatures, ranging from 5 to 40 degrees C, and developmental rates were modeled as a function of temperature. Sancassania rodionovi completed immature development in 17.35 +/- 0.58 and 20.17 +/- 0.88 d at 25 degrees C on button and oyster mushrooms, respectively. When the mite fed on button mushroom, the rate of development increased gradually from 10 to 35 degrees C. Using a linear model, the developmental zero was estimated to be 3.50 degrees C with a thermal constant of 357.14 degree-days. The Logan 10, Briere 1, and Thermodynamic models adequately described the data for this mite and yielded R2 values >0.95; these models provided estimates of optimum temperature for development of 33.244, 32.145, and 32.148 degrees C, respectively. Understanding the influence of temperature on development of S. rodionovi is discussed with respect to pest management in mushroom production.  相似文献   
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A procedure is described for the synthetic incorporation into membrane proteins of the non-natural amino acid TOAC (2,2,6,6-tetramethyl-piperidine-1-oxyl-4-amino-4-carboxylic acid), which is coupled rigidly to the alpha-carbon, providing direct detection of peptide backbone dynamics by electron paramagnetic resonance (EPR). Also included is a protocol for the functional reconstitution of the spin-labeled protein in lipid vesicles. This protocol can be completed in 17 d.  相似文献   
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We have used electron paramagnetic resonance (EPR) to probe the homo- and heterooligomeric interactions of reconstituted sarcoplasmic reticulum Ca-ATPase (SERCA) and its regulator phospholamban (PLB). SERCA is responsible for restoring calcium to the sarcoplasmic reticulum to allow muscle relaxation, whereas PLB inhibits cardiac SERCA unless phosphorylated at Ser16. To determine whether changes in protein association play essential roles in regulation, we detected the microsecond rotational diffusion of both proteins using saturation transfer EPR. Peptide synthesis was used to create a fully functional and monomeric PLB mutant with a spin label rigidly coupled to the backbone of the transmembrane helix, while SERCA was reacted with a Cys-specific spin label. Saturation transfer EPR revealed that sufficiently high lipid/protein ratios minimized self-association for both proteins. Under these dilute conditions, labeled PLB was substantially immobilized after co-reconstitution with unlabeled SERCA, reflecting their association to form the regulatory complex. Ser16 phosphorylation slightly increased this immobilization. Complementary measurements with labeled SERCA showed no change in mobility after co-reconstitution with unlabeled PLB, regardless of its phosphorylation state. We conclude that phosphorylating monomeric PLB can relieve SERCA inhibition without changes in the oligomeric states of these proteins, indicating a structural rearrangement within the heterodimeric regulatory complex.  相似文献   
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