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991.
Although a greater degree of personal obesity is associated with weaker negativity toward overweight people on both explicit (i.e., self-report) and implicit (i.e., indirect behavioral) measures, overweight people still prefer thin people on average. We investigated whether the national and cultural context – particularly the national prevalence of obesity – predicts attitudes toward overweight people independent of personal identity and weight status. Data were collected from a total sample of 338,121 citizens from 71 nations in 22 different languages on the Project Implicit website (https://implicit.harvard.edu/) between May 2006 and October 2010. We investigated the relationship of the explicit and implicit weight bias with the obesity both at the individual (i.e., across individuals) and national (i.e., across nations) level. Explicit weight bias was assessed with self-reported preference between overweight and thin people; implicit weight bias was measured with the Implicit Association Test (IAT). The national estimates of explicit and implicit weight bias were obtained by averaging the individual scores for each nation. Obesity at the individual level was defined as Body Mass Index (BMI) scores, whereas obesity at the national level was defined as three national weight indicators (national BMI, national percentage of overweight and underweight people) obtained from publicly available databases. Across individuals, greater degree of obesity was associated with weaker implicit negativity toward overweight people compared to thin people. Across nations, in contrast, a greater degree of national obesity was associated with stronger implicit negativity toward overweight people compared to thin people. This result indicates a different relationship between obesity and implicit weight bias at the individual and national levels.  相似文献   
992.
In a cross sectional study, 19 French and 23 Colombian cases of confirmed active ocular toxoplasmosis (OT) were evaluated. The objective was to compare clinical, parasitological and immunological responses and relate them to the infecting strains. A complete ocular examination was performed in each patient. The infecting strain was characterized by genotyping when intraocular Toxoplasma DNA was detectable, as well as by peptide-specific serotyping for each patient. To characterize the immune response, we assessed Toxoplasma protein recognition patterns by intraocular antibodies and the intraocular profile of cytokines, chemokines and growth factors. Significant differences were found for size of active lesions, unilateral macular involvement, unilateral visual impairment, vitreous inflammation, synechiae, and vasculitis, with higher values observed throughout for Colombian patients. Multilocus PCR-DNA sequence genotyping was only successful in three Colombian patients revealing one type I and two atypical strains. The Colombian OT patients possessed heterogeneous atypical serotypes whereas the French were uniformly reactive to type II strain peptides. The protein patterns recognized by intraocular antibodies and the cytokine patterns were strikingly different between the two populations. Intraocular IFN-γ and IL-17 expression was lower, while higher levels of IL-13 and IL-6 were detected in aqueous humor of Colombian patients. Our results are consistent with the hypothesis that South American strains may cause more severe OT due to an inhibition of the protective effect of IFN-γ.  相似文献   
993.
TRU-016 is a SMIPTM (monospecific protein therapeutic) molecule against the tetraspanin transmembrane family protein CD37 that is currently in Phase 2 trials in Chronic Lymphocytic Leukemia (CLL) and Non-Hodgkin Lymphoma (NHL). In an attempt to enhance the ADCC function of SMIP-016, the chimeric version of TRU-016, SMIP-016GV was engineered with a modification in a glycosylation site in the Fc domain. The wild-type and glycovariant SMIP proteins mediate comparable Type I antibody-like direct cytotoxicity in the presence of anti-human Fc crosslinker and show a similar tyrosine phosphorylation pattern post-treatment. However, NK cells stimulated with the SMIP-016GV exhibit enhanced activation and release 3-fold more interferon-γ compared with SMIP-016. SMIP-016GV shows enhanced ADCC function against cells expressing CD37 with NK cell effectors derived from both normal and CLL-affected individuals. Enhanced ADCC is observed against CLL cells and is sustained at concentrations of SMIP-016GV as low at 5E−6 µg/mL on cells expressing minimal CD37 antigen. In support of the biological relevance of this, SMIP-016GV mediates effective ADCC against primary acute lymphoblastic leukemia (ALL) cells with low surface expression of CD37. Collectively, these data suggest potential use of the novel therapeutic agent SMIP-016GV with enhanced effector function for B cell malignancies, including CLL and ALL therapy.  相似文献   
994.
995.
Liu J  Zhu Y  Chen I  Lau J  He F  Lau A  Wang Z  Karuppannan AK  Kwang J 《Journal of virology》2007,81(17):9560-9567
Porcine circovirus type 2 (PCV2) is the primary causative agent of an emerging swine disease, postweaning multisystemic wasting syndrome. We previously showed that a newly identified protein, ORF3, plays a major role in virus-induced apoptosis and is involved in viral pathogenesis in vitro and in vivo. To characterize the role of the ORF3 protein in modulation of cellular function, a yeast two-hybrid system was used to screen a porcine cDNA library to find its interacting partner. We have isolated and characterized pPirh2 (for "porcine p53-induced RING-H2"), an E3 ubiquitin ligase, which specifically interacts with the ORF3 protein of PCV2. This interaction was further confirmed when the ORF3 protein coimmunoprecipitated with and colocalized to pPirh2 in PK15 cells. The ORF3 protein has been found to interact with the p53 binding domain of pPirh2 in yeast cells. Expression of the protein results in less pPirh2 expression in PCV2-infected cells. Furthermore, increases in p53 expression were observed in PCV2-infected and ORF3 (alone)-transfected cells. Phosphorylation of p53 at Ser-46, which is related to p53-induced apoptosis, was also time-dependently activated in PCV-infected and ORF3-transfected cells. Taken together, our results show that the PCV2 ORF3 protein specifically interacts with pPirh2 and inhibits its stabilization; this may lead to increasing p53 expression, resulting in apoptosis.  相似文献   
996.
The enzyme CP4 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19) from Agrobacterium tumefaciens CP4, encoded by the aroA gene, has been used for the construction of genetically modified crops resistant to total herbicide glyphosate. During the study of possible horizontal gene transfer of aroA CP4 gene from genetically modified food in gastrointestinal tract to bacterial community living in the animal gut, we have discovered and characterized truncated form of aroA CP4 within the cloning experiments in Escherichia coli. We have compared properties of the recombinant E. coli strains with both CP4 EPSPS enzyme forms.  相似文献   
997.
In this study, we investigated protein and genetic profiles of Kunitz trypsin inhibitors (KTIs) in seeds of 16 different soybean genotypes that included four groups consisting of wild soybean (Glycine soja), the cultivated soybean (G. max) ancestors of modern N. American soybean cultivars (old), modern N. American soybean (elite), and Asian cultivated soybean landraces that were the immediate results of domestication from the wild soybean. Proteins were well separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and stained protein cut from a 2D-PAGE indicated that KTI exists as multiple isoforms (spots) in soybean. Protein spots of KTI were identified and characterized using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Although overall distribution patterns of the KTI protein spots appeared similar, the number and intensity of the protein spots between wild and cultivated genotypes varied. Three KTI peptides were identified in three of the wild genotypes, PI 393551, PI 407027 and PI 407282, in which KTI3 peptide showed highest intensity. The remaining wild genotype, PI 366120, showed four protein spots. In contrast, the ancestors, modern and Asian landrace genotypes showed only two protein spots corresponding to KTI. On the basis of DNA blot analysis, there is one copy of the KTI3 gene in all 16 genotypes. Polymorphism was detected in one of the wild genotypes (PI 366120) both in proteomic and genomic analyses. Our data suggest that the major variation of protein profiles were between wild and cultivated soybean genotypes rather than among genotypes in the same group. Genetic variation of KTI1, KTI2 and KTI3-related genes were detected within and between groups.  相似文献   
998.
Two proteins that mediate bile acid export from the ileal enterocyte, organic solute transporter (OST)-alpha and -beta, have recently been identified. It is unclear whether these two proteins associate directly and how they interact to mediate transport function and membrane localization. In this study, the protein-protein interactions, transport functions, and membrane localization of human (h)OST-alpha and -beta proteins were examined. The results demonstrated that coexpression of hOST-alpha and -beta in transfected cells resulted in a three- to fivefold increase of the initial rate of taurocholate influx or efflux compared with cells expressing each protein individually and nontransfected cells. Confocal microscopy demonstrated plasma membrane colocalization of hOST-alpha and -beta proteins in cells cotransfected with hOST-alpha and -beta cDNAs. Protein-protein interactions between hOST-alpha and -beta were demonstrated by mammalian two-hybrid and coimmunoprecipitation analyses. Truncation of the amino-terminal 50 amino acid extracellular residues of hOST-alpha abolished its interaction with hOST-beta and led to an intracellular accumulation of the two proteins and to only background levels of taurocholate transport. In contrast, carboxyl-terminal 28 amino acid truncated hOST-alpha still interacted with hOST-beta, and majority of this cytoplasmic tail-truncated protein was expressed on the basolateral membrane when it was stably cotransfected with hOST-beta protein in Madin-Darby canine kidney cells. In summary, hOST-alpha and -beta proteins are physically associated. The intracellular carboxyl-terminal domain of hOST-alpha is not essential for this interaction with hOST-beta. The extracellular amino-terminal fragment of hOST-alpha may contain important information for the assembly of the heterodimer and trafficking to the plasma membrane.  相似文献   
999.
The highly complex nature of interactions of Mycobacterium tuberculosis with cells of the immune system has puzzled researchers the world-over in understanding the pathogenesis and immunology associated with tuberculosis (TB). This has contributed to the delay in development of effective vaccine(s) for TB. Several excellent studies have provided only a glimpse of the kind and degree of immune responses elicited following infection by mycobacteria. Preferred entry via respiratory route results in the capture of mycobacteria by alveolar macrophages that eventually become their long-term hosts. Since the pathogen is rarely cleared this has resulted in the human population serving as a large reservoir for mycobacteria. Owing to their unique ability to prime na?ve and memory T cells, dendritic cells (DCs) play important and indispensable roles in the initiation and maintenance of protective immune responses following infection. The kind of immune response initiated by DCs with respect to mycobacteria determines the character of immune responses mounted by the host against the pathogen. The profile of cytokines and chemokines secreted as a result of infection of DCs by mycobacteria further plays an important role in defining the course of infection. This minireview attempts to highlight key interactions of mycobacteria with dendritic cells. We discus the uptake of mycobacteria by DCs followed by DC activation and the spectrum of immune responses initiated by infected/activated DCs, followed by numerous ways the pathogen has devised to subvert protective responses.  相似文献   
1000.
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