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91.
Objective To observe NLRP3 inflammasome expression and inflammatory cells infiltration in the BSA-overloaded rats kidney, and to investigate the potential mechanism of renal injury induced by proteinuria. Methods After unilateral right nephrectomy, eighteen healthy male Wistar rats were randomly divided into two groups: protein overload nephropathy model group (n=10), treated with intraperitoneal injections of bovine serum albumin (BSA); control group (n=8), treated with intraperitoneal injections of 0.9% saline for 9 weeks. Body weigh were measured every week and 24 h urine were collected in 0, 2, 5, 7, 9 week. The plasma levels of blood total protein (TP), albumin (Alb), serum creatinine (Scr) and blood urea nitrogen (BUN) were determined by automatic analyzers. Renal pathological changes were evaluated by PAS and Masson stains. Immunohistochemical staining was used to detect the expression of NLRP3, caspase-1, IL-1β, and IL-18, as well as the types of inflammatory cells. The NLRP3, caspase-1, IL-1β, and IL-18 protein and mRNA levels were also analyzed by Western blot and real-time PCR in two groups. Results It was found that there was a significant increase of proteinuria and BUN in model group compare to that in control group (all P<0.05). However, there were no significant changes in body weight, TP, Alb and Scr between the two groups. Morphological study demonstrated that renal tubular epithelial cell injury, proteinaceous casts in tubular lumen, accompanying with the dominant macrophages and lymphocytes infiltration in interstitium in model group. The immunohistochemistry showed that there were more T (CD3+), B cells (CD20+) and macrophages (CD68+) in renal interstitium in model group than that in control group (P<0.05). Tubulointerstitial injury score was higher than that of the control group (P<0.05). Immunohistochemistry, Western blot and real-time PCR all showed that the expression of NLRP3, caspase-1, IL-18 and IL-1 β were significantly increased compared to those in control group (P<0.05). Furthermore, there were significant correlations between proteinuria and IL-1β/IL-18 expression (P<0.05). Conclusion NLRP3 inflammasome activation is involved in tubulointerstitial inflammation caused by proteinuria.  相似文献   
92.
目的探讨改良的Schatzker分型对复杂胫骨平台骨折制定术前计划的指导作用,使术前计划更充分,减少术中误判。方法 2006年3月至2013年10月,对58例需要切开复位及内固定的常规SchatzkerⅤ型、Ⅵ型胫骨平台骨折,随机分成对照组及实验组,每组29例,对照组进行Schatzker分型,实验组进行改良的Schatzker分型,并分别确定手术入路、内固定物放置位置及数量,比较两种分型对手术进路、内固定物放置位置及数量的正确率,比较两种分型对指导治疗方案的满意度。结果根据改良的Schatzker分型,对SchatzkerⅤ型、Ⅵ型骨折患者进行手术入路选择,确定内固定物放置位置及数量,进行术前计划和术中观察,对关节面的复位及主要问题骨的显露和直接固定的正确率为100%,而根据常规Schatzker分型,对SchatzkerⅤ型、Ⅵ型胫骨平台骨折选择手术入路、内固定物放置位置及数量,正确率为86.36%,差异有统计学意义。结论根据改良的Schatzker分型,对需要切开复位及内固定的复杂胫骨平台骨折,选择手术入路及内固定物放置位置及数量更准确,使术前计划更充分,减少术中误判,术中证明对关节面及主要问题骨的复位更好,对主要问题骨的固定更直接,更准确。  相似文献   
93.
Alternative splicing (AS) is a crucial step in gene expression. It is subject to intricate regulation, and its deregulation in cancer can lead to a wide array of neoplastic phenotypes. A large body of evidence implicates splice isoforms in most if not all hallmarks of cancer, including growth, apoptosis, invasion and metastasis, angiogenesis, and metabolism. AS has important clinical implications since it can be manipulated therapeutically to treat cancer and represents a mechanism of resistance to therapy. In prostate cancer (PCa) AS also plays a prominent role and this review will summarize the current knowledge of alternatively spliced genes with important functional consequences. We will highlight accumulating evidence on AS of the components of the two critical pathways in PCa: androgen receptor (AR) and phosphoinositide 3-kinase (PI3K). These observations together with data on dysregulation of splice factors in PCa suggest that AR and PI3K pathways may be interconnected with previously unappreciated splicing regulatory networks. In addition, we will discuss several lines of evidence implicating splicing regulation in the development of the castration resistance.  相似文献   
94.
BACKGROUND: The endothelial cell protein C receptor (EPCR) presents protein C to the thrombin:thrombomodulin complex on the endothelium of large vessels, and enhances the generation of activated protein C (APC) and activation of protease-activated receptor-1. A previous report has demonstrated binding of soluble (s) EPCR to activated neutrophils via surface proteinase 3 (PR3). METHODS: We now report further characterization of this interaction. Activated neutrophils and purified PR3 both decrease endothelial cell (EC) surface EPCR, suggestive of its proteolysis. RESULTS: When added to purified recombinant sEPCR, PR3 produced multiple cleavages, with early products including 20 kDa N-terminal and C-terminal (after Lys(176)) fragments. The binding of active site blocked PR3 to sEPCR was studied by surface plasmon resonance. Estimates of the K(D) of 18.5-102 nM were obtained with heterogeneous binding, suggestive of more than a single interaction site. CONCLUSIONS: This work demonstrates PR3 binding to and proteolysis of EPCR and suggests a mechanism by which anticoagulant and cell protective pathways can be down-regulated during inflammation.  相似文献   
95.
96.
目的观察温肾活血方对RCS大鼠视网膜感光细胞凋亡的影响。方法纯合子RCS大鼠16只在出生后14 d随机分为2组,即模型组、治疗组,每组8只,另8只SD大鼠作为正常对照组。治疗组予温肾活血方灌胃治疗,而模型组及对照组予蒸馏水灌胃治疗,连续治疗28 d。HE染色观察视网膜各层细胞形态和结构的变化,TUNEL荧光染色观察视网膜外核层细胞凋亡情况。免疫组化荧光染色测定视网膜Caspase-3,Bax,Bcl-2的表达。结果(1)HE染色:治疗后28 d,RCS大鼠各组视网膜外核层较对照组明显变薄,感光细胞数量明显减少,但治疗组较模型组视网膜更厚,感光细胞数更多。(2)TUNEL检测:治疗后28 d,RCS大鼠各组视网膜外核层凋亡细胞计数较对照组明显增多,3组间比较差异有显著统计学意义(F=71.58,P=0.000);与模型组比较,治疗组凋亡细胞计数显著减少(t=4.74,P=0.001)。(3)免疫组化:治疗后28 d,3组间比较,视网膜Caspase-3(F=59.37,P=0.000)、Bcl-2(F=31.35,P=0.000)表达水平差异有统计学意义;与模型组比较,治疗组Caspase-3表达显著减少(t=2.36,P=0.040),Bcl-2表达显著增多(t=3.15,P=0.010),均有统计学意义。结论温肾活血方可以抑制RCS大鼠视网膜感光细胞凋亡,其作用可能与抑制Caspase-3的表达并促进Bcl-2的表达有关。  相似文献   
97.
Stress during pregnancy has been implicated as a risk factor for the development of many mental disorders; however, the influence of prenatal stress on the fear or anxiety-related behaviors, especially the fear extinction in adult offspring has been little investigated. In order to investigate how prenatal stress affects fear extinction, which is regarded as a form of new learning that counteracts the expression of Pavlovian's conditioned fear, a rat model of prenatal chronic mild stress (PNS) was used to evaluate the effects of PNS on fear extinction in adult offspring. The expression of hippocampal glycogen synthase kinase-3s (GSK-3α, β), N-methyl-d-aspartic acid receptors (NMDARs)-2B and the hippocampal cell proliferation in dentate gyrus in the adult offspring during fear extinction were studied. Our results showed that PNS significantly reduced body weight of pups, indicating PNS might induce growth retardation in offspring. Moreover, PNS significantly enhanced the freezing behavior of offspring at the phase of extinction, suggesting PNS impaired the abilities of fear extinction learning. In addition, PNS significantly increased the levels of GSK-3α, β and NR2B, but reduced hippocampal cell proliferation during fear extinction. Taken together, our findings suggest that maternal stress during pregnancy can impair the fear extinction of adult offspring, probably by affecting the neural plasticity of brain.  相似文献   
98.

Background

Mutations of POLR3A and POLR3B have been reported to cause several allelic hypomyelinating disorders, including hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome). Patients and methods: To clarify the difference in MRI between the two genotypes, we reviewed MRI in three patients with POLR3B mutations, and three with POLR3A mutations. Results: Though small cerebellar hemispheres and vermis are common MRI findings with both types of mutations, MRI in patients with POLR3B mutations revealed smaller cerebellar structures, especially vermis, than those in POLR3A mutations. MRI also showed milder hypomyelination in patients with POLR3B mutations than those with POLR3A mutations, which might explain milder clinical manifestations. Conclusions: MRI findings are distinct between patients with POLR3A and 3B mutations, and can provide important clues for the diagnosis, as these patients sometimes have no clinical symptoms suggesting 4H syndrome.  相似文献   
99.
It is believed that glycogen synthase kinase‐3 hyperphosphorylates tau protein in progressive supranuclear palsy (PSP). The Tau Restoration on PSP (TAUROS) trial assessed the glycogen synthase kinase‐3 inhibitor tideglusib as potential treatment. For the magnetic resonance imaging (MRI) substudy reported here, we assessed the progression of brain atrophy. TAUROS was a multinational, phase 2, double‐blind, placebo‐controlled trial in patients with mild‐to‐moderate PSP who were treated with oral tideglusib (600 mg or 800 mg daily) or with placebo for 1 year. A subset of patients underwent baseline and 52‐week MRI. Automated, observer‐independent, atlas‐based, and mask‐based volumetry was done on high‐resolution, T1‐weighted, three‐dimensional data. For primary outcomes, progression of atrophy was compared both globally (brain, cerebrum) and regionally (third ventricle, midbrain, pons) between the active and placebo groups (Bonferroni correction). For secondary outcomes, 15 additional brain structures were explored (Benjamini & Yekutieli correction). In total, MRIs from 37 patient were studied (placebo group, N = 9; tideglusib 600 mg group, N = 19; tideglusib 800 mg group, N = 9). The groups compared well in their demographic characteristics. Clinical results showed no effect of tideglusib over placebo. Progression of atrophy was significantly lower in the active group than in the placebo group for the brain (mean ± standard error of the mean: ?1.3% ± 1.4% vs. ?3.1% ± 2.3%, respectively), cerebrum (?1.3% ± 1.5% vs. ?3.2% ± 2.1%, respectively), parietal lobe (?1.6% ± 1.9% vs. ?4.1% ± 3.0%, respectively), and occipital lobe (?0.3% ± 1.8% vs. ?2.7% ± 3.2%, respectively). A trend toward reduced atrophy also was observed in the frontal lobe, hippocampus, caudate nucleus, midbrain, and brainstem. In patients with PSP, tideglusib reduced the progression of atrophy in the whole brain, particularly in the parietal and occipital lobes. © 2014 International Parkinson and Movement Disorder Society  相似文献   
100.
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