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51.
目的:探究小肠CT及双气囊小肠镜诊断克罗恩病患者的差异性。方法:选择2017年4月至2019年3月于我院接受治疗的60例克罗恩病患者,分别实施小肠CT及双气囊小肠镜检测,对比两种检测方式对克罗恩病患者诊断准确率及病变范围、病变位置、活动度和并发症的检测差异。结果:CT检出克罗恩病的准确率96.67%,双气囊小肠镜检出克罗恩病的准确率为93.33%,其差异无统计学意义(P>0.05)。小肠CT主要表现为肠腔狭窄50例(83.33%),肠壁增厚52例(86.67%),肠外淋巴结46例(76.67%),肠系膜水肿及血管改变21例(35.00%),肠外炎症10例(16.67%),瘘管3例(5.00%),瘘道1例(1.67%);双气囊小肠镜表现为环形溃疡、不规则溃疡、环状溃疡等共计46例(76.67%),阿弗他溃疡22例(36.67%),黏膜充血、水肿等26例(43.33%),结节样增生6例(10.00%),小肠肠腔节段性狭窄16例(26.67%),假性息肉9例(15.00%);经病理学检测表现为淋巴细胞、中性粒细胞、嗜酸性粒细胞等炎性浸润,淋巴组织及肉芽组织出现增生小肠CT发现肠外炎症、瘘道、瘘管等合计14例,而双气囊小肠镜未发现并发症。结论:相比于双气囊小肠镜,小肠CT能够更为准确的判断克罗恩病患者是否处于炎症状态,也能够更有效的发现肠外并发症的存在,但小肠CT及双气囊小肠镜联合应用监测效果更佳。  相似文献   
52.
Spodoptera frugiperda (J. E. Smith) is a highly adaptable polyphagous migratory pest in tropical and subtropical regions. Small heat shock proteins (sHsps) are molecular chaperones that play important roles in the adaptation to various environment stressors. The present study aimed to clarify the response mechanisms of S. frugiperda to various environmental stressors. We obtained five S. furcifera sHsp genes (SfsHsp21.3, SfsHsp20, SfsHsp20.1, SfsHsp19.3, and SfsHsp29) via cloning. The putative proteins encoded by these genes contained a typical α-crystallin domain. The expression patterns of these genes during different developmental stages, in various tissues of male and female adults, as well as in response to extreme temperatures and UV-A stress were studied via real-time quantitative polymerase chain reaction. The results showed that the expression levels of all five SfsHsp genes differed among the developmental stages as well as among the different tissues of male and female adults. The expression levels of most SfsHsp genes under extreme temperatures and UV-A-induced stress were significantly upregulated in both male and female adults. In contrast, those of SfsHsp20.1 and SfsHsp19.3 were significantly downregulated under cold stress in male adults. Therefore, the different SfsHsp genes of S. frugiperda play unique regulatory roles during development as well as in response to various environmental stressors.  相似文献   
53.
microRNAs (miRNAs) contained in small extracellular vesicles (sEVs) are candidates for non-invasive biomarkers. Oxaliplatin (L-OHP) has been approved for advanced colorectal cancer (CRC) chemotherapy. However, the response to L-OHP differs among CRC patients. In addition, CRC cells often acquire the resistance to L-OHP. This study aimed at the prediction of L-OHP sensitivity by measuring extracellular miRNAs levels. Firstly, we compared intracellular miRNAs expressions in L-OHP-sensitive CRC cells (SW620 and HCT116 cells) with those in acquired and intrinsic L-OHP-resistant cells. In microarray and real-time RT-PCR analyses, the intracellular miR-33a-5p, miR-210–3p, and miR-224–5p expressions were lower in acquired and intrinsic L-OHP-resistant CRC cells than sensitive cells. Furthermore, in SW620 cells, L-OHP sensitivity was decreased by miR-33a-5p inhibitor. On the other hand, miR-210–3p or miR-224–5p inhibitor did not affect L-OHP sensitivity in SW620 cells. Secondly, the amount of miR-33a-5p, miR-210–3p, and miR-224–5p in sEVs was compared. The amount of miR-33a-5p and miR-210–3p in sEVs secreted from acquired and intrinsic L-OHP-resistant cells tended to be small. miR-224–5p was not detected in sEVs secreted from three types of CRC cells examined. To the best of our knowledge, this is the first study demonstrating that miR-33a-5p and/or miR-210–3p in sEVs would be candidates for biomarkers of L-OHP sensitivity. In particular, miR-33a-5p is a promising candidate because it would be directly involved in L-OHP sensitivity.  相似文献   
54.

Background

Gas trapping quantified on chest CT scans has been proposed as a surrogate for small airway disease in COPD. We sought to determine if measurements using paired inspiratory and expiratory CT scans may be better able to separate gas trapping due to emphysema from gas trapping due to small airway disease.

Methods

Smokers with and without COPD from the COPDGene Study underwent inspiratory and expiratory chest CT scans. Emphysema was quantified by the percent of lung with attenuation < −950HU on inspiratory CT. Four gas trapping measures were defined: (1) Exp−856, the percent of lung < −856HU on expiratory imaging; (2) E/I MLA, the ratio of expiratory to inspiratory mean lung attenuation; (3) RVC856-950, the difference between expiratory and inspiratory lung volumes with attenuation between −856 and −950 HU; and (4) Residuals from the regression of Exp−856 on percent emphysema.

Results

In 8517 subjects with complete data, Exp−856 was highly correlated with emphysema. The measures based on paired inspiratory and expiratory CT scans were less strongly correlated with emphysema. Exp−856, E/I MLA and RVC856-950 were predictive of spirometry, exercise capacity and quality of life in all subjects and in subjects without emphysema. In subjects with severe emphysema, E/I MLA and RVC856-950 showed the highest correlations with clinical variables.

Conclusions

Quantitative measures based on paired inspiratory and expiratory chest CT scans can be used as markers of small airway disease in smokers with and without COPD, but this will require that future studies acquire both inspiratory and expiratory CT scans.  相似文献   
55.

Methods

Combining small-angle X-ray and neutron scattering measurements with inelastic neutron scattering experiments, we investigated the impact of high hydrostatic pressure on the structure and dynamics of β-lactoglobulin (βLG) in aqueous solution.

Background

βLG is a relatively small protein, which is predominantly dimeric in physiological conditions, but dissociates to monomer below about pH 3.

Results

High-pressure structural results show that the dimer–monomer equilibrium, as well as the protein–protein interactions, are only slightly perturbed by pressure, and βLG unfolding is observed above a threshold value of 3000 bar. In the same range of pressure, dynamical results put in evidence a slowing down of the protein dynamics in the picosecond timescale and a loss of rigidity of the βLG structure. This dynamical behavior can be related to the onset of unfolding processes, probably promoted from water penetration in the hydrophobic cavity.

General significance

Results suggest that density and compressibility of water molecules in contact with the protein are key parameters to regulate the protein flexibility.  相似文献   
56.
57.
Disrupted-in-schizophrenia 1 (DISC1) is a multifunctional scaffold protein which plays an important role in neurogenesis and neural development in the adult brain, especially in the dentate gyrus (DG) of the hippocampus. Accumulated research has unveiled the role of DISC1 in several aspects of neural development and neurogenesis, such as neuronal maturation, proliferation, migration, positioning, differentiation, dendritic growth, axonal outgrowth, and synaptic plasticity. Studies on the function of this protein have explored multiple facets, including variants and missense mutants in genetics, proteins interactivity and signaling pathways in molecular biology, and pathogenesis and treatment targets of major mental illness, and more. In this review, we present several signaling pathways discussed in recent research, such as the AKT signaling pathway, GABA signaling pathway, GSK3β signaling pathway, Wnt signaling pathway, and NMDA-R signaling pathway. DISC1 interacts, directly or indirectly, with these signaling pathways and they co-regulate the process of adult neurogenesis in the hippocampus.  相似文献   
58.
The sequence of the chloroplast genome, which is inherited maternally, contains useful information for many scientific fields such as plant systematics, biogeography and biotechnology because its characteristics are highly conserved among species. There is an increase in chloroplast genomes of angiosperms that have been sequenced in recent years. In this study, the nucleotide sequence of the chloroplast genome (cpDNA) of Veratrum patulum Loes. (Melanthiaceae, Liliales) was analyzed completely. The circular double-stranded DNA of 153,699 bp consists of two inverted repeat (IR) regions of 26,360 bp each, a large single copy of 83,372 bp, and a small single copy of 17,607 bp. This plastome contains 81 protein-coding genes, 30 distinct tRNA and four genes of rRNA. In addition, there are six hypothetical coding regions (ycf1, ycf2, ycf3, ycf4, ycf15 and ycf68) and two open reading frames (ORF42 and ORF56), which are also found in the chloroplast genomes of the other species. The gene orders and gene contents of the V. patulum plastid genome are similar to that of Smilax china, Lilium longiflorum and Alstroemeria aurea, members of the Smilacaceae, Liliaceae and Alstroemeriaceae (Liliales), respectively. However, the loss rps16 exon 2 in V. patulum results in the difference in the large single copy regions in comparison with other species. The base substitution rate is quite similar among genes of these species. Additionally, the base substitution rate of inverted repeat region was smaller than that of single copy regions in all observed species of Liliales. The IR regions were expanded to trnH_GUG in V. patulum, a part of rps19 in L. longiflorum and A. aurea, and whole sequence of rps19 in S. china. Furthermore, the IGS lengths of rbcL-accD-psaI region were variable among Liliales species, suggesting that this region might be a hotspot of indel events and the informative site for phylogenetic studies in Liliales. In general, the whole chloroplast genome of V. patulum, a potential medicinal plant, will contribute to research on the genetic applications of this genus.  相似文献   
59.
Some physico-chemical properties of R140G and K141Q mutants of human small heat shock protein HspB1 associated with hereditary peripheral neuropathy were analyzed. Mutation K141Q did not affect intrinsic Trp fluorescence and interaction with hydrophobic probe bis-ANS, whereas mutation R140G decreased both intrinsic fluorescence and fluorescence of bis-ANS bound to HspB1. Both mutations decreased thermal stability of HspB1. Mutation R140G increased, whereas mutation K141Q decreased the rate of trypsinolysis of the central part (residues 5–188) of HspB1. Both the wild type HspB1 and its K141Q mutant formed large oligomers with apparent molecular weight ∼560 kDa. The R140G mutant formed two types of oligomers, i.e. large oligomers tending to aggregate and small oligomers with apparent molecular weight ∼70 kDa. The wild type HspB1 formed mixed homooligomers with R140G mutant with apparent molecular weight ∼610 kDa. The R140G mutant was unable to form high molecular weight heterooligomers with HspB6, whereas the K141Q mutant formed two types of heterooligomers with HspB6. In vitro measured chaperone-like activity of the wild type HspB1 was comparable with that of K141Q mutant and was much higher than that of R140G mutant. Mutations of homologous hot-spot Arg (R140G of HspB1 and R120G of αB-crystallin) induced similar changes in the properties of two small heat shock proteins, whereas mutations of two neighboring residues (R140 and K141) induced different changes in the properties of HspB1.  相似文献   
60.
Gallbladder carcinoma (GBC) is one of the mostly aggressive and fatal malignancies. However, little is known about the oncogenic genes that contributed to the development of GBC. Zinc finger X-chromosomal protein (ZFX) was a novel member of the Krueppel C2H2-type zinc-finger protein family and its down-regulation led to impaired cell growth in human laryngeal squamous cell carcinoma. Here, we aim to investigate the function of ZFX in GBC cell proliferation and migration. Loss of function analysis was performed on GBC cell line (GBC-SD) using lentivirus-mediated siRNA against ZFX. The proliferation, in vitro tumorigenesis (colony-formation) ability as well as cell migration was significantly suppressed after GBC-SD cells which were infected with ZFX-siRNA-expressing lentivirus (Lv-shZFX). Our finding suggested that ZFX promoted the growth and migration of GBC cells and could present a potential molecular target for gene therapy of GBC.  相似文献   
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