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41.
Expressed proteins and antigens from Neospora caninum tachyzoites were studied by two-dimensional gel electrophoresis and immunoblot analysis combined with matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Thirty-one spots corresponding to 20 different proteins were identified from N. caninum tachyzoites by peptide mass fingerprinting. Six proteins were identified from a N. caninum database (NTPase, 14-3-3 protein homologue, NcMIC1, NCDG1, NcGRA1 and NcGRA2), and 11 proteins were identified in closely related species using the T. gondii database (HSP70, HSP60, pyruvate kinase, tubulin alpha- and beta-chain, putative protein disulfide isomerase, enolase, actin, fructose-1,6-bisphosphatase, lactate dehydrogenase and glyceradehyde-3-phosphate dehydrogenase). One hundred and two antigen spots were observed using pH 4-7 IPG strips on immunoblot profiles. Among them, 17 spots corresponding to 11 antigenic proteins were identified from a N. caninum protein map. This study involved the construction of in-depth protein maps for N. caninum tachyzoites, which will be of value for studies of its pathogenesis, drug and vaccine development, and phylogenetic studies. 相似文献
42.
The exact timing ofAnguilla japonica spawning was determined from analyses of daily otolith increments in leptocephali collected near a spawning area west of
the Mariana Islands on July 1–18, 1991. The birth dates of the 54 leptocephali examined (10.2 to 30.5 mm in total length)
ranged from May 22 to June 24, 1991, the individuals clearly comprising two age groups, May-born fish (mode May 28) and June-born
fish (mode June 21). The data showed thatA. japonica spawns intermittently during the spawning season, with fixed synchronized timing. Each group of leptocephali collected along
three different north-south transects (131°, 134° and 137°E between 10° and 22°N) comprised both May-born and June-born fish.
The latter were dominant along the easternmost and middle transects, whereas the May-born fish were more abundant along the
westernmost transect. The modal ages of the June-born and May-born fish collected along 137°E on July 1–3 were 13 d and 35
d, respectively, while those of the two age groups collected along 134°E on July 17 and 18 were 28 d and 50 d, respectively.
These data show that the interval between the sampling dates for the two transects (ca. 15 d) corresponded closely to the
differences in modal ages of specimens from the two transects (15 d) for both the May- and June-born fish, and further, that
the difference in modal age between the two age groups (22 d) was the same at both transects. A similar correspondence in
total length was also observed between the two age groups at the above two transects. The findings clearly demonstrated parallel
westward transport by the North Equatorial Current for both the May- and June-born eel leptocephali, which originated from
a spawning area estimated as being between 141° and 143°E. 相似文献
43.
The outbreak of coronavirus disease 2019 (COVID-19) has not only affected human health but also diverted the focus of research and derailed the world economy over the past year. Recently, vaccination against COVID-19 has begun, but further studies on effective therapeutic agents are still needed. The severity of COVID-19 is attributable to several factors such as the dysfunctional host immune response manifested by uncontrolled viral replication, type I interferon suppression, and release of impaired cytokines by the infected resident and recruited cells. Due to the evolving pathophysiology and direct involvement of the host immune system in COVID-19, the use of immune-modulating drugs is still challenging. For the use of immune-modulating drugs in severe COVID-19, it is important to balance the fight between the aggravated immune system and suppression of immune defense against the virus that causes secondary infection. In addition, the interplaying events that occur during virus–host interactions, such as activation of the host immune system, immune evasion mechanism of the virus, and manifestation of different stages of COVID-19, are disjunctive and require thorough streamlining. This review provides an update on the immunotherapeutic interventions implemented to combat COVID-19 along with the understanding of molecular aspects of the immune evasion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may provide opportunities to develop more effective and promising therapeutics. 相似文献
44.
Jong Hyuk Lee Chang Min Park Sang Joon Park Jae Seok Bae Sang Min Lee Jin Mo Goo 《PloS one》2015,10(5)
ObjectivesTo retrospectively investigate the added value of quantitative 3D shape analysis in differentiating encapsulated from invasive thymomas.ResultsSignificant differences were observed between encapsulated and invasive thymomas, in terms of cystic changes (p=0.004), sphericity (p=0.016), and discrete compactness (p=0.001). Subsequent binary logistic regression analysis revealed that absence of cystic change (adjusted odds ratio (OR) = 6.636; p=0.015) and higher discrete compactness (OR = 77.775; p=0.012) were significant differentiators of encapsulated from invasive thymomas. ROC analyses revealed that the addition of 3D shape analysis to clinical and CT features (AUC, 0.955; 95% CI, 0.935–0.975) provided significantly higher performance in differentiating encapsulated from invasive thymomas than clinical and CT features (AUC, 0.666; 95% CI, 0.626–0.707) (p<0.001).ConclusionAddition of 3D shape analysis, particularly discrete compactness, can improve differentiation of encapsulated thymomas from invasive thymomas. 相似文献
45.
Soo Min Han Byungjin Hwang Tae-gun Park Do-Il Kim Moo-Yong Rhee Byoung-Kwon Lee Young Keun Ahn Byung Ryul Cho Jeongtaek Woo Seung-Ho Hur Jin-Ok Jeong Sungha Park Yangsoo Jang Min Goo Lee Duhee Bang Ji Hyun Lee Sang-Hak Lee 《PloS one》2015,10(5)
Familial hypercholesterolemia (FH) is a genetic disorder with an increased risk of early-onset coronary artery disease. Although some clinically diagnosed FH cases are caused by mutations in LDLR, APOB, or PCSK9, mutation detection rates and profiles can vary across ethnic groups. In this study, we aimed to provide insight into the spectrum of FH-causing mutations in Koreans. Among 136 patients referred for FH, 69 who met Simon Broome criteria with definite family history were enrolled. By whole-exome sequencing (WES) analysis, we confirmed that the 3 known FH-related genes accounted for genetic causes in 23 patients (33.3%). A substantial portion of the mutations (19 of 23 patients, 82.6%) resulted from 17 mutations and 2 copy number deletions in LDLR gene. Two mutations each in the APOB and PCSK9 genes were verified. Of these anomalies, two frameshift deletions in LDLR and one mutation in PCSK9 were identified as novel causative mutations. In particular, one novel mutation and copy number deletion were validated by co-segregation in their relatives. This study confirmed the utility of genetic diagnosis of FH through WES. 相似文献
46.
47.
High temperature requirement A2 (HtrA2)/Omi is a serine protease localized in mitochondria. In response to apoptotic stimuli, HtrA2 is released to the cytoplasm and cleaves many proteins, including XIAP, Apollon/BRUCE, WT1, and Ped/Pea-15, to promote apoptosis. However, the function of HtrA2 in mitochondria under normal conditions remains unclear. Here, we show that the mitochondrial proteins, LON protease 1 (LONP1) and prohibitin (PHB), are overexpressed in HtrA2−/− mouse embryonic fibroblast (MEF) cells and HtrA2 knock-down HEK293T cells. We also confirm the effect of the HtrA2 protease on the stability of the above mitochondrial quality control proteins in motor neuron degeneration 2 (mnd2) mice, which have a greatly reduced protease activity as a result of a Ser276Cys missense mutation of the HtrA2 gene. In addition, PHB interacts with and is directly cleaved by HtrA2. Luminescence assays demonstrate that the intracellular ATP level is decreased in HtrA2−/− cells compared to HtrA2+/+ cells. HtrA2 deficiency causes a decrease in the mitochondrial membrane potential, and reactive oxygen species (ROS) generation is greater in HtrA2−/− cells than in HtrA2+/+ cells. Our results implicate that HtrA2 might be an upstream regulator of mitochondrial homeostasis. 相似文献
48.
Patar Ebenezer Sitorus Hoon Cheol Park Doyoung Byun Nam Seo Goo Cheol Heui Han 《仿生工程学报(英文版)》2010,7(4):354-363
We conducted a comprehensive study to investigate the aerodynamic characteristics and force generation of the elytra of abeetle,Allomyrina dichotoma.Our analysis included wind tunnel experiments and three-dimensional computational fluiddynamics simulations using ANSYS-CFX software.Our first approach was a quasi-static study that considered the effect ofinduced flapping flow due to the flapping motion of the fore-wings (elytra) at a frequency of around 30 Hz to 40 Hz.The dihedralangle was varied to represent flapping motion during the upstroke and downstroke.We found that an elytron producespositive lift at 0° geometric angle of attack,negative lift during the upstroke,and always produces drag during both the upstrokeand downstroke.We also found that the lift coefficient of an elytron does not drop even at a very high geometric angle of attack.For a beetle with a body weight of 5 g,based on the quasi-static method,the fore-wings (elytra) can produce lift of less than 1%of its body weight. 相似文献
49.
Min MG Song DJ Miller M Cho JY McElwain S Ferguson P Broide DH 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(8):5321-5328
Environmental tobacco smoke (ETS) can increase asthma symptoms and the frequency of asthma attacks. However, the contribution of ETS to airway remodeling in asthma is at present unknown. In this study, we have used a mouse model of allergen-induced airway remodeling to determine whether the combination of chronic exposure to ETS and chronic exposure to OVA allergen induces greater levels of airway remodeling than exposure to either chronic ETS or chronic OVA allergen alone. Mice exposed to chronic ETS alone did not develop significant eosinophilic airway inflammation, airway remodeling, or increased airway hyperreactivity to methacholine. In contrast, mice exposed to chronic OVA allergen had significantly increased levels of peribronchial fibrosis, increased thickening of the smooth muscle layer, increased mucus, and increased airway hyperreactivity which was significantly enhanced by coexposure to the combination of chronic ETS and chronic OVA allergen. Mice coexposed to chronic ETS and chronic OVA allergen had significantly increased levels of eotaxin-1 expression in airway epithelium which was associated with increased numbers of peribronchial eosinophils, as well as increased numbers of peribronchial cells expressing TGF-beta1. These studies suggest that chronic coexposure to ETS significantly increases levels of allergen-induced airway remodeling (in particular smooth muscle thickness) and airway responsiveness by up-regulating expression of chemokines such as eotaxin-1 in airway epithelium with resultant recruitment of cells expressing TGF-beta1 to the airway and enhanced airway remodeling. 相似文献
50.