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951.

Background

Our previous studies have demonstrated that piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) may develop significant thymus atrophy, which related to thymocytes apoptosis. However, apart from that detected in the thymus, there are no reports describing cell apoptosis induced by HP-PRRSV infection. In this study, we analyzed comparatively the pathological changes, cell apoptosis and viral load in peripheral immune organs including tonsil, inguinal lymph nodes (ILNs) and spleen and lungs following experimental infection of piglets with HP-PRRSV HuN4 and classical PRRSV CH-1a.

Findings

HP-PRRSV HuN4 exhibited much stronger cell tropism than CH-1a in immune organs and lungs of piglets. HuN4 infection led to the serious injuries in tonsils, ILNs, spleens and lungs, especially apoptosis in these organs was significant.

Conclusions

HuN4 infection induced severe lesions (gross pathology, histopathology and cell apoptosis) in the peripheral immune organs and lungs of infected piglets. Large numbers of apoptotic cells in immune organs and lung induced by HuN4 may play a role in the pathogenesis of the HP-PRRS and the distinct injuries caused by HuN4 infection may be associated with the high mortality rate of HP-PRRS in pigs.  相似文献   
952.
953.
Human leukocyte antigen DPB1 was reported to contain singly nucleotide polymorphisms conferring the strongest susceptibility to systemic sclerosis in Korean population. However, associations of specific DPB1 alleles with SSc vary in different ethnic populations. The aim of this study was to profile DPB1 alleles in Chinese population and to identify specific DPB1 alleles in association with SSc and clinical and serological features of SSc in Han Chinese. A cohort containing 338 patients with SSc and 480 gender-matched and unrelated controls were examined in the study. The HLA-DPB1 genotyping was performed with sequence-based typing method. Exact p-values were obtained (Fisher''s test) from 2×2 tables of allele counts or allele carriers and disease status. Thirty eight DPB1 alleles were found in the cohort. DPB1*05:01 was the most common allele in this cohort. DPB1*03:01 and *13:01 were significantly increased in SSc. DPB1*13:01 association had already been described in other ethnic populations, whereas DPB1*03:01 was specific to Han Chinese patients with SSc. In addition, comparisons between SSc subsets indicated that patients carrying DPB1*03:01 were more likely to develop pulmonary fibrosis, DPB1*04 carriers were increased in SSc patients with anti-centromere autoantibodies and in contrast, SSc patients with homozygous DPB1*05:01 showed an opposite association with marginal significance.  相似文献   
954.
Abstract

We report our strategies to prepare TSAO compounds carrying at 5′-position groups, such as amines, that may be positively charged at physiological conditions, unexpectedly, cyclic TSAO-derivatives were obtained. A possible mechanism for the formation of these unexpected compounds is advanced.  相似文献   
955.
Cytokines are important modulators in the interactions between the host immune system and malignant tumor. Of these, Interleukin-10 (IL-10) is an important immunoregulatory cytokine mainly produced by macrophages and T lymphocytes. To date, a number of studies investigated the role of the IL-10-819C>T polymorphism in the aetiology of cancers of various organs. However, the results of these studies remain inconclusive. So, we carried out a meta-analysis on all eligible case-control studies to estimate the overall cancer risk of IL-10-819C>T polymorphism as well as to quantify the between-study heterogeneity and potential bias. This meta-analysis, including 8157 cases and 10 473 controls from 29 published case–control studies, explored the association between a potentially functional polymorphism, -819C>T within the IL-10 promoter region and cancer risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. The results provided evidence that the IL-10-819C>T polymorphism was associated with a significant decrease in overall cancer risk. In the stratified analyses, the risk remained for studies of “other cancer”, smoking-related cancer, Asian populations and hospital-based studies. This meta-analysis identified an evidence of the association between the IL-10-819C>T and cancer risk, especially in “other cancer”, smoking-related cancers, Asians and hospital-based studies. Further large case–control studies, especially studies in African population were needed to validate our results.  相似文献   
956.

Background

Cross-species comparisons of gene neighborhoods (also called genomic contexts) in microbes may provide insight into determining functionally related or co-regulated sets of genes, suggest annotations of previously un-annotated genes, and help to identify horizontal gene transfer events across microbial species. Existing tools to investigate genomic contexts, however, lack features for dynamically comparing and exploring genomic regions from multiple species. As DNA sequencing technologies improve and the number of whole sequenced microbial genomes increases, a user-friendly genome context comparison platform designed for use by a broad range of users promises to satisfy a growing need in the biological community.

Results

Here we present JContextExplorer: a tool that organizes genomic contexts into branching diagrams. We implement several alternative context-comparison and tree rendering algorithms, and allow for easy transitioning between different clustering algorithms. To facilitate genomic context analysis, our tool implements GUI features, such as text search filtering, point-and-click interrogation of individual contexts, and genomic visualization via a multi-genome browser. We demonstrate a use case of our tool by attempting to resolve annotation ambiguities between two highly homologous yet functionally distinct genes in a set of 22 alpha and gamma proteobacteria.

Conclusions

JContextExplorer should enable a broad range of users to analyze and explore genomic contexts. The program has been tested on Windows, Mac, and Linux operating systems, and is implemented both as an executable JAR file and java WebStart. Program executables, source code, and documentation is available at http://www.bme.ucdavis.edu/facciotti/resources_data/software/.  相似文献   
957.
Stem cell transplantation has shown promising regenerative effects against neural injury, and photobiomodulation (PBM) can aid tissue recovery. This study aims to evaluate the therapeutic effect of human umbilical cord mesenchymal stem cells (hUCMSCs) and laser alone or combined on spinal cord injury (SCI). The animals were divided into SCI, hUCMSCs, laser treatment (LASER) and combination treatment (hUCMSCs + LASER) groups. Cell‐enriched grafts of hUCMSCs (1 × 106 cells/ml) were injected at the site of antecedent trauma in SCI model rats. A 2 cm2 damaged area was irradiated with 630 nm laser at 100 mW/cm2 power for 20 min. Locomotion was evaluated using Basso–Beattie–Bresnahan (BBB) scores, and neurofilament repair were monitored by histological staining and diffusion tensor imaging (DTI). First, after SCI, the motor function of each group was restored with different degrees, the combination treatment significantly increased the BBB scores compared to either monotherapy. In addition, Nissl bodies were more numerous, and the nerve fibers were longer and thicker in the combination treatment group. Consistent with this, the in situ expression of NF‐200 and glial fibrillary acidic protein in the damaged area was the highest in the combination treatment group. Finally, DTI showed that the combination therapy optimally improved neurofilament structure and arrangement. These results may show that the combination of PBM and hUCMSCs transplantation is a feasible strategy for reducing secondary damage and promoting functional recovery following SCI.  相似文献   
958.
959.
Alba (Acetylation lowers binding affinity) domain is a small, dimeric nucleic acid-binding domain, which is widely distributed in archaea and numbers of eukaryotes. Alba domain containing proteins have been reported to be involved in many cellular processes, such as regulation of translation, maintaining genome stability, regulation of RNA processing and so on. In Trypanosoma brucei (T. brucei), there are four Alba proteins identified, which are named TbAlba1 to TbAlba4. However, the structure and function of TbAlba proteins are still unknown. Here, we solved the crystal structure of TbAlba1 to a resolution of 2.46 Å. TbAlba1 adopts a similar Alba-fold, which comprises of four β-strands (β1-β4) and three long α-helices (α1-α3). Furthermore, TbAlba1 displays some structural features quite different from other Alba proteins. These differences may imply the diverse biological roles of Alba family members.  相似文献   
960.
A new racemic xanthone, garmckeanin A ( 1 ), and eight known analogs 2 – 9 were isolated from the ethyl acetate (AcOEt) extract of the Vietnamese Garcinia mckeaniana leaves. Their structures were determined by MS and NMR spectral analyses and compared with the literature. The AcOEt extract showed good cytotoxicity against cancer cell lines KB, Lu, Hep-G2 and MCF7, with IC50 values of 5.40–8.76 μg/mL, and it also possessed α-glucosidase inhibitory activity, with an IC50 value of 9.17 μg/mL. Garmckeanin A ( 1 ) exhibited inhibition of all cancer cell lines, with an IC50 value of 7.3–0.9 μM. Allanxanthone C ( 5 ) successfully controlled KB growth, with an IC50 value of 0.54 μM, higher than that of the positive control, ellipticine (IC50 1.22 μM). Norathyriol ( 8 ) was a promising α-glucosidase inhibitor, with an IC50 value of 0.07 μM, much higher than that of the positive control, acarbose (IC50 161.0 μM). The interactions of the potential α-glucosidase inhibitors with the C- and N-terminal domains of human intestinal α-glucosidase were also investigated by molecular docking study. The results indicated that bannaxanthone D ( 2 ), garcinone E ( 4 ), bannaxanthone E ( 6 ), and norathyriol ( 8 ) exhibit higher binding affinity to the C-terminal than to the N-terminal domain through essential residues in the active sites. In particular, compound 8 could be assumed to be the most potent mixed inhibitor.  相似文献   
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