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71.
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   
72.
Rabbit alveolar macrophages exhibit a chemiluminescent response which is associated with phagocytosis of zymosan and polystyrene-butadiene particles. The chemiluminescence reaches a peak in 15 to 25 minutes and then gradually diminishes over the next 1 to 3 hours. During the time of maximal light emission there appears to be no actual uptake of particles, but the response is dependent upon the particle concentration. The metabolic inhibitor, DNP (2,4-dinitrophenol), causes a rapid inhibition of the chemiluminescent response. The addition of ATP to the medium prior to exposure of the cells to particles causes the chemiluminescent response to be greatly diminished, i.e., 0.3mM ATP virtually abolishes the response. These experiments suggest that some metabolic response of the cell to phagocytosis is responsible for the chemiluminescence.  相似文献   
73.
Neurobiological and neuroimaging studies have emphasized the structural and functional alterations in the striatum of cirrhotic patients, but alterations in the functional connections between the striatum and other brain regions have not yet been explored. Of note, manganese accumulation in the nervous system, frequently reflected by hyperintensity at the bilateral globus pallidus (GP) on T1-weighted imaging, has been considered a factor affecting the striatal and cortical functions in hepatic decompensation. We employed resting-state functional magnetic resonance imaging to analyze the temporal correlation between the striatum and the remaining brain regions using seed-based correlation analyses. The two-sample t-test was conducted to detect the differences in corticostriatal connectivity between 44 cirrhotic patients with hyperintensity at the bilateral GP and 20 healthy controls. Decreased connectivity of the caudate was detected in the anterior/middle cingulate gyrus, and increased connectivity of the caudate was found in the left motor cortex. A reduction in functional connectivity was found between the putamen and several regions, including the anterior cingulate gyrus, right insular lobe, inferior frontal gyrus, left parahippocampal gyrus, and anterior lobe of the right cerebellum; increased connectivity was detected between the putamen and right middle temporal gyrus. There were significant correlations between the corticostriatal connectivity and neuropsychological performances in the patient group, but not between the striatal connectivity and GP signal intensity. These alterations in the corticostriatal functional connectivity suggested the abnormalities in the intrinsic brain functional organiztion among the cirrhotic patients with manganese deposition, and may be associated with development of metabolic encephalopathy. The manganese deposition in nervous system, however, can not be an independent factor predicting the resting-state brain dysfunction in real time.  相似文献   
74.
There is an urgent need for new therapeutic avenues to improve the outcome of patients with glioblastoma multiforme (GBM). Current studies have suggested that cucurbitacin I, a natural selective inhibitor of JAK2/STAT3, has a potent anticancer effect on a variety of cancer cell types. This study showed that autophagy and apoptosis were induced by cucurbitacin I. Exposure of GBM cells to cucurbitacin I resulted in pronounced apoptotic cell death through activating bcl-2 family proteins. Cells treatment with cucurbitacin I up-regulated Beclin 1 and triggered autophagosome formation and accumulation as well as conversion of LC3I to LC3II. Activation of the AMP-activated protein kinase/mammalian target of rapamycin/p70S6K pathway, but not the PI3K/AKT pathway, occurred in autophagy induced by cucurbitacin I, which was accompanied by decreased hypoxia-inducible factor 1α. Stable overexpression of hypoxia-inducible factor 1α induced by FG-4497 prevented cucurbitacin I-induced autophagy and down-regulation of bcl-2. Knockdown of beclin 1 or treatment with the autophagy inhibitor 3-methyladenine also inhibited autophagy induced by cucurbitacin I. A coimmunoprecipitation assay showed that the interaction of Bcl-2 and Beclin 1/hVps34 decreased markedly in cells treated with cucurbitacin I. Furthermore, knockdown of beclin 1 or treatment with the lysosome inhibitor chloroquine sensitized cancer cells to cucurbitacin I-induced apoptosis. Finally, a xenograft model provided additional evidence for the occurrence of cucurbitacin I-induced apoptosis and autophagy in vitro. Our findings provide new insights into the molecular mechanisms underlying cucurbitacin I-mediated GBM cell death and may provide an efficacious therapy for patients harboring GBM.  相似文献   
75.
Intestinal mucosal injuries are directly or indirectly related to many common acute and chronic diseases. Long non-coding RNAs (lncRNAs) are expressed in many diseases, including intestinal mucosal injury. However, the relationship between lncRNAs and intestinal mucosal injury has not been determined. Here, we investigated the functions and mechanisms of action of lncRNA Bmp1 on damaged intestinal mucosa. We found that Bmp1 was increased in damaged intestinal mucosal tissue and Bmp1 overexpression was able to alleviate intestinal mucosal injury. Bmp1 overexpression was found to influence cell proliferation, colony formation, and migration in IEC-6 or HIEC-6 cells. Moreover, miR-128-3p was downregulated after Bmp1 overexpression, and upregulation of miR-128-3p reversed the effects of Bmp1 overexpression in IEC-6 cells. Phf6 was observed to be a target of miR-128-3p. Furthermore, PHF6 overexpression affected IEC-6 cells by activating PI3K/AKT signaling which was mediated by the miR-128-3p/PHF6 axis. In conclusion, Bmp1 was found to promote the expression of PHF6 through the sponge miR-128-3p, activating the PI3K/AKT signaling pathway to promote cell migration and proliferation.Subject terms: Cell growth, Cell migration  相似文献   
76.
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   
77.
Unlike the human lung, monopodial canine airway branching follows an irregular dichotomized pattern with fractal features. We studied three canine airway molds and found a self-similarity feature from macro- to microscopic scales, which formed a fractal set up to seven scales in the airways. At each fractal scale, lateral branches evenly lined up along an approximately straight main trunk to form three to four two-dimensional structures, and each lateral branch was the monopodial main trunk of the next fractal scale. We defined this pattern as the fractal main lateral-branching pattern, which exhibited similar structures from macro- to microscopic scales, including lobes, sublobes, sub-sublobes, etc. We speculate that it, rather than a mother-daughter pattern, could better describe the actual asymmetrical architecture of the monopodial canine airway.  相似文献   
78.
79.
水生鳞翅类——螟蛾科水螟亚科   总被引:3,自引:2,他引:1  
尤平 《昆虫知识》2005,42(5):595-598
从成虫、卵、幼虫、蛹及生物学等方面介绍了鳞翅目的主要水生类群———螟蛾科水螟亚科Nymphulinae的主要特征及其幼虫的主要生活类型。水螟幼虫的生活型可分为Nymphula型、Parapoynx型、Potamomusa型、Eoophyla型和Nymphicula型。各生活型的主要类群及生活特征也予以说明。目的是为了使读者对该类群有正确的认识,以引起人们的重视。  相似文献   
80.
家蚕转基因载体pBacA3EG的构建及其表达   总被引:2,自引:0,他引:2  
以家蚕Bombyx mori肌动蛋白A3(actin 3)启动子、增强性绿色荧光蛋白(enhanced green fluorescent protein, EGFP)基因及SV40的多聚腺苷酸识别序列为元件,经多次克隆,将其插入到piggyBac转座载体中。经PCR、酶切鉴定及测序表明各元件已按正确的方式插入到piggyBac载体中。将构建好的piggyBac表达载体显微注射到胚盘形成前期的蚕卵中,在胚胎早期发育的第3天,通过体视荧光显微镜检测到蚕卵内发出较强的绿色荧光。结果表明该载体构建正确且能在蚕卵中进行表达。家蚕转基因载体的体外瞬时表达不但是成功进行家蚕转基因所必需的第一步,而且其自身也可以应用于基因的功能研究,为家蚕后基因组研究奠定了基础。  相似文献   
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