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1.
Brucella cell surface protein (BCSP31) is potentially useful for diagnosing brucellosis. We aimed to establish a monoclonal antibody (MAb) against Brucella melitensis BCSP31 and to investigate its distribution in diagnosis. Soluble recombinant BCSP31 was successfully expressed and purified. Two MAbs (1F1 and 1E5) against B. melitensis BCSP31, effective in detecting both recombinant and cellular proteins, were obtained and characterized. The MAbs did not react with Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Mycobacterium tuberculosis, or Bacillus aeruginosus, but strongly reacted with BCSP31 and B. melitensis by ELISA and Western blot analysis. We also tested different Brucella species and brucellosis using the prepared anti-BCSP31 MAbs. BCSP31 and anti-BCSP31 MAbs may play important roles in future research in diagnosing brucellosis.  相似文献   
2.
Compelling evidence suggests the limitation and shortcomings of the current and well established cell culture method using multi-well plates, flasks and Petri dishes. These are particularly important when cell functions are sensitive to the local microenvironment, cell–cell and cell–extracellular matrix interactions. There is a clear need for advanced cell culture systems which mimic in vivo and more physiological conditions. This review summarises and analyses recent progress in three dimensional (3D) cell culture with perfusion as the next generation cell culture tools, while excluding engineered tissue culture where three dimensional scaffold has to be used for structural support and perfusion for overcoming mass transfer control. Apart from research activities in academic community, product development in industry is also included in this review.  相似文献   
3.
This research was aimed at estimating possible Coal workers’ pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males’ life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.  相似文献   
4.
A new polypore, Perenniporia tibetica, collected in Xizang (Tibet), southwestern China, is described and illustrated on the basis of morphological and molecular characters. Perenniporia tibetica is characterized by an annual growth habit, resupinate basidiocarps with a creambuff to pinkish-buff pore surface and white to cream-colored rhizomorphs, a dimitic hyphal system with slightly dextrinoid and distinctly cyanophilous skeletal hyphae, and basidiospores that are ellipsoid, truncate or not, strongly dextrinoid, and cyanophilous, 6.7–8.7 × 5.3–6.8 μm. Its preliminary phylogenetic relationships are inferred based on sequence data from the ribosomal ITS and LSU regions, both suggesting that P. tibetica forms a distinct lineage in the genus Perenniporia.  相似文献   
5.
The fecundity reduction with aging is referred as the reproductive aging which comes earlier than that of chronological aging. Since humans have postponed their childbearing age, to prolong the reproductive age becomes urgent agenda for reproductive biologists. In the current study, we examined the potential associations of α‐ketoglutarate (α‐KG) and reproductive aging in mammals including mice, swine, and humans. There is a clear tendency of reduced α‐KG level with aging in the follicle fluids of human. To explore the mechanisms, mice were selected as the convenient animal model. It is observed that a long term of α‐KG administration preserves the ovarian function, the quality and quantity of oocytes as well as the telomere maintaining system in mice. α‐KG suppresses ATP synthase and alterations of the energy metabolism trigger the nutritional sensors to down‐regulate mTOR pathway. These events not only benefit the general aging process but also maintain ovarian function and delay the reproductive decline. Considering the safety of the α‐KG as a naturally occurring molecule in energy metabolism, its utility in reproduction of large mammals including humans deserves further investigation.  相似文献   
6.
Pseudorabies, a herpesvirus infection, is mainly controlled by using attenuated live vaccines. In this study, the effect of ginseng stem and leaf saponins (GSLS) in combination with selenium (Se; in the form of sodium selenite) on vaccination against attenuated pseudorabies virus (aPrV) was evaluated. It was found that GSLS and Se have an adjuvant effect and that a combination of GSLS and Se stimulates significantly enhanced immune responses than does GSLS or Se alone. Following oral administration of GSLS, mice immunized with an attenuated PrV vaccine diluted in Se‐containing physiological saline solution (PSS) provoked a significantly stronger gB‐specific serum antibodies response (IgG, IgG1 and IgG2a), enhanced lymphocyte proliferation and cytolytic activity of NK cells, along with higher production of cytokines (IFN‐γ, IL‐12, IL‐5 and IL‐10) by splenocytes. Notably, the combination of GSLS and Se conferred a much higher resistance to fPrV challenge after immunization of the mice with aPrV vaccine. This study offers convincing experimental evidence that an injection of Se with oral GSLS is a promising adjuvant combination that improves the efficacy of vaccination against PrV and deserves further study regarding improvement of responses to other animal vaccines.  相似文献   
7.
Although CD133 has been reported to be a promising colon cancer stem cell marker, the biological functions of CD133+ colon cancer cells remain controversial. In the present study, we investigated the biological differences between CD133+ and CD133 colon cancer cells, with a particular focus on their interactions with cancer-associated fibroblasts, especially CD10+ fibroblasts. We used 19 primary colon cancer tissues, 30 primary cultures of fibroblasts derived from colon cancer tissues and 6 colon cancer cell lines. We isolated CD133+ and CD133 subpopulations from the colon cancer tissues and cultured cells. In vitro analyses revealed that the two populations showed similar biological behaviors in their proliferation and chemosensitivity. In vivo analyses revealed that CD133+ cells showed significantly greater tumor growth than CD133 cells (P = 0.007). Moreover, in cocultures with primary fibroblasts derived from colon cancer tissues, CD133+ cells exhibited significantly more invasive behaviors than CD133 cells (P<0.001), especially in cocultures with CD10+ fibroblasts (P<0.0001). Further in vivo analyses revealed that CD10+ fibroblasts enhanced the tumor growth of CD133+ cells significantly more than CD10 fibroblasts (P<0.05). These data demonstrate that the in vitro invasive properties and in vivo tumor growth of CD133+ colon cancer cells are enhanced in the presence of specific cancer-associated fibroblasts, CD10+ fibroblasts, suggesting that the interactions between these specific cell populations have important roles in cancer progression. Therefore, these specific interactions may be promising targets for new colon cancer therapies.  相似文献   
8.
Spines or trichomes on the fruit of cucumbers enhance their commercial value in China. In addition, glabrous mutants exhibit resistance to aphids and therefore their use by growers can reduce pesticide residues. Previous studies have reported two glabrous mutant plants containing the genes, csgl1 and csgl2. In the present study, a new glabrous mutant, NCG157, was identified showing a gene interaction effect with csgl1 and csgl2. This mutant showed the glabrous character on stems, leaves, tendrils, receptacles and ovaries, and there were no spines or tumors on the fruit surface. Inheritance analysis showed that a single recessive gene, named csgl3, determined the glabrous trait. An F2 population derived from the cross of two inbred lines 9930 (a fresh market type from Northern China that exhibits trichomes) and NCG157 (an American processing type with glabrous surfaces) was used for genetic mapping of the csgl3 gene. By combining bulked segregant analysis (BAS) with molecular markers, 18 markers, including two simple sequence repeats (SSR), nine insertion deletions (InDel) and seven derived cleaved amplified polymorphism sequences (dCAPs), were identified to link to the csgl3 gene. All of the linked markers were used as anchor loci to locate the csgl3 gene on cucumber chromosome 6. The csgl3 gene was mapped between the dCAPs markers dCAPs-21 and dCAPs-19, at genetic distances of 0.05 cM and 0.15 cM, respectively. The physical distance of this region was 19.6 kb. Three markers, InDel-19, dCAPs-2 and dCAPs-11, co-segregated with csgl3. There were two candidate genes in the region, Csa6M514860 and Csa6M514870. Quantitative real-time PCR showed that the expression of Csa6M514870 was higher in the tissues of 9930 than that of NCG157, and this was consistent with their phenotypic characters. Csa6M514870 is therefore postulated to be the candidate gene for the development of trichomes in cucumber. This study will facilitate marker-assisted selection (MAS) of the smooth plant trait in cucumber breeding and provide for future cloning of csgl3.  相似文献   
9.
Levels of neurofilament subunits, potential biomarkers of motor axon breakdown, are increased in amyotrophic lateral sclerosis (ALS) patient's CSF but data on blood are not available. We measured blood levels of the phosphorylated axonal form of neurofilament H (pNF-H) by ELISA in transgenic rodent models of superoxide dismutase 1 (SOD1) ALS, and in 20 ALS patients and 20 similar aged controls monthly for 4 months. All symptomatic rodent ALS models showed robust levels of blood pNF-H, while control rodents or mice transgenic for unmutated SOD1 showed no detectable blood pNF-H. Average pNF-H levels in the G93A SOD1 mouse progressively increased from day 74 through death (day ∼130). Median blood pNF-H level in ALS patients was 2.8-fold higher than controls ( p  < 0.001). Median ALSFRS-R declined a median of 0.8 pt/month ( p  < 0.001); higher baseline pNF-H level appeared to be associated with faster ALSFRS-R decline over 4 months ( p  = 0.087). The median rate of decline in ALSFRS-R was 1.9 pt/month in patients with baseline pNF-H levels above the median pNF-H value of 0.53 ng/mL; ALSFRS-R declined at a median of 0.6 pt/month in patients below this level. The pNF-H levels were relatively stable month to month in individual patients, raising questions regarding the molecular pathogenesis of ALS. Baseline control human pNF-H levels were higher in men than women and increased minimally over time. These data suggest that blood pNF-H can be used to monitor axonal degeneration in ALS model rodents and support further study of this protein as a potential biomarker of disease prognosis in ALS patients.  相似文献   
10.
The phase behavior of mixtures formed with palmitic acid (PA) and one of the following sterols (dihydrocholesterol, ergosterol, 7-dehydrocholesterol, stigmasterol and stigmastanol), in a PA/sterol molar ratio of 3/7, has been characterized by IR and 2H NMR spectroscopy at different pH. Our study shows that it is possible to form liquid-ordered (lo) lamellar phases with these binary non-phospholipid mixtures. The characterization of alkyl chain dynamics of PA in these systems revealed the large ordering effect of the sterols. It was possible to extrude these systems, using standard extrusion techniques, to form large unilamellar vesicles (LUVs), except in the case of ergosterol-containing mixture. The resulting LUVs displayed a very limited passive permeability consistent with the high sterol concentration. In addition, the stability of these PA/sterol self-assembled bilayers was also found to be pH-sensitive, therefore, potentially useful as nanovectors. By examining different sterols, we could establish some correlations between the structure of these bilayers and their permeability properties. The structure of the side chain at C17 of the sterol appears to play a prime role in the mixing properties with fatty acid.  相似文献   
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