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91.
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by neuronal degeneration and inflammation in the nerves. The role of the immune system has been concentrated by researchers in the etiopathogenesis of the disease. Given the inhibitory roles of regulatory T cells (Tregs), it is expected that increasing or activating their populations in patients with ALS can have significant therapeutic effects. Here we searched databases, including CENTRAL, MEDLINE, CINAHL Plus, clinicaltrials.gov , and ICTRP for randomized clinical trials (RCTs) and non-RCTs until March 2019. For preclinical studies, we searched PubMed, Scopus, and Google Scholar up to June 2019. We also included preclinical studies, due to the lack of clinical information available, which used Tregs (or directly targeting them) for treating mice models of ALS. We identified 29 records (CENTRAL 7, MEDLINE 4, CINAHL Plus 8, and clinicaltrials.gov 10) and removed 10 duplicated publications. After screening, we identified one RCT which had been published as an abstract, three non-RCTs, and four ongoing studies. We also identified 551 records (PubMed 446, Google Scholar 68, and Scopus 37) for preclinical studies and performed a meta-analysis. Finally, we found three papers that matched our inclusion criteria for preclinical studies. Results indicated the effectiveness of the application of Tregs in the treatment of ALS. Our meta-analysis on preclinical studies revealed that Tregs significantly prolonged survival in mice models of ALS. Overall, our analysis testified that exertion of Tregs in the treatment of ALS is a promising approach, that notwithstanding, requires further evaluations.  相似文献   
92.
The current basement membrane (BM) model proposes a single-layered extracellular matrix (ECM) sheet that is predominantly composed of laminins, collagen IVs and proteoglycans. The present data show that BM proteins and their domains are asymmetrically organized providing human BMs with side-specific properties: A) isolated human BMs roll up in a side-specific pattern, with the epithelial side facing outward and the stromal side inward. The rolling is independent of the curvature of the tissue from which the BMs were isolated. B) The epithelial side of BMs is twice as stiff as the stromal side, and C) epithelial cells adhere to the epithelial side of BMs only. Side-selective cell adhesion was also confirmed for BMs from mice and from chick embryos. We propose that the bi-functional organization of BMs is an inherent property of BMs and helps build the basic tissue architecture of metazoans with alternating epithelial and connective tissue layers.  相似文献   
93.

INTRODUCTION:

We studied the impact of small ubiquitin-like modifier 4 (SUMO4) M55V polymorphism on susceptibility to diabetic nephropathy in Iranian type 2 diabetes patients.

MATERIALS AND METHODS:

The patient group consisted of 50 Iranian type 2 diabetes patients with nephropathy, and the control group consisted of 50 Iranian type 2 diabetes patients without nephropathy. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism method for the M55V.

RESULTS:

The frequency of SUMO4 AA, AG, and GG genotypes were 23%, 18%, and 9% in the patient group and 10%, 22%, and 18% in the control group. There was no significant difference in frequency of SUMO4 genotypes in patients compared to controls.

CONCLUSION:

These findings indicate that SUMO4 M55V polymorphism is not associated with diabetic nephropathy in Iranian type 2 diabetes patients.  相似文献   
94.
Molecular Biology Reports - Vinblastine and vincristine are two important anti-cancer drugs that are synthesized by the Terpenoid Indole Alkaloids (TIAs) pathway in periwinkle (Catharanthus...  相似文献   
95.

Longtail tuna (Thunnus tonggol) is a neritic species that supports commercial, artisanal and recreational fisheries throughout the Indo-Pacific region. Historically receiving little attention by commercial fisheries, the global annual catch of longtail tuna has steadily risen from around 30,000 t in the early 1980s to exceeding 200,000 t since 2004, reaching a peak of 291,264 t in 2007, and was 281,613 t in 2017. Catches of longtail tuna in the Indian Ocean now exceed catches of principal commercial target species, such as albacore and bigeye tunas. A sequence of stock assessments undertaken throughout the species’ range since the late 1980s persistently indicated that at least three of the four stocks defined in this paper are likely to have been, and most likely are currently, subject to overfishing and overfished as a result of excess fishing effort on this relatively slow-growing and long-lived tuna species. As the spawning biomass of principal tuna target species continue to decline in both the Indian and western and central Pacific Oceans, the increasing catches of longtail tuna, other neritic tunas, and seerfishes is worrisome. Few conservation and management measures (CMMs) are currently in place specifically for longtail tuna, although in recent years some coastal States, Regional Fishery Bodies, and tuna Regional Fisheries Management Organisations have begun to develop initiatives to improve the catch and biological data quality for longtail tuna and sympatric species of neritic tunas and tuna-like species. This paper provides a global review of biological, ecological and fishery information to provide researchers, fishery managers and policy makers with the most current information from which to begin to guide future stock assessment and the development of CMMs for longtail tuna.

  相似文献   
96.
Vegetatively expressed insecticidal proteins (VIPs) produced by Bacillus thuringiensis fall into several classes of which the third, VIP3, is known for their activity against several key Lepidopteran pests of commercial broad acre crops and because their mode of action does not overlap with that of crystalline insecticidal proteins. The details of the VIP3 structure and mode of action have remained obscure for the quarter century that has passed since their discovery. In the present article, we report the first crystal structure of a full‐length VIP3 protein. Crystallization of this target required multiple rounds of construct optimization and screening—over 200 individual sequences were expressed and tested. This protein adopts a novel global fold that combines domains with hitherto unreported topology and containing elements seemingly borrowed from carbohydrate‐binding domains, lectins, or from other insecticidal proteins.  相似文献   
97.
Levels of IgG and IgM autoantibodies (AA) to malondialdehyde (MDA)-LDL and apoB-immune complexes (ICs) were measured in 748 cases and 1,723 controls in the EPIC-Norfolk cohort and their association to coronary artery disease (CAD) events determined. We evaluated whether AA and IC modify CAD risk associated with secretory phospholipase A(2) (sPLA(2)) type IIA mass and activity, lipoprotein-associated PLA(2) activity, lipoprotein (a) [Lp(a)], oxidized phospholipids on apoB-100 (OxPL/apoB), myeloperoxidase, and high sensitivity C-reactive protein. IgG ICs were higher in cases versus controls (P = 0.02). Elevated levels of IgM AA and IC were inversely associated with Framingham Risk Score and number of metabolic syndrome criteria (p range 0.02-0.001). In regression analyses adjusted for age, smoking, diabetes, LDL-cholesterol, HDL-cholesterol, and systolic blood pressure, the highest tertiles of IgG and IgM AA and IC were not associated with higher risk of CAD events compared with the lowest tertiles. However, elevated levels of IgM IC reduced the risk of Lp(a) (P = 0.006) and elevated IgG MDA-LDL potentiated the risk of sPLA(2) mass (P = 0.018). This epidemiological cohort of initially healthy subjects shows that IgG and IgM AA and IC are not independent predictors of CAD events but may modify CAD risk associated with elevated levels of oxidative biomarkers.  相似文献   
98.
Bacteriophage phiKZ is a giant phage that infects Pseudomonas aeruginosa, a human pathogen. The phiKZ virion consists of a 1450?? diameter icosahedral head and a 2000??-long contractile tail. The structure of the whole virus was previously reported, showing that its tail organization in the extended state is similar to the well-studied Myovirus bacteriophage T4 tail. The crystal structure of a tail sheath protein fragment of phiKZ was determined to 2.4?? resolution. Furthermore, crystal structures of two prophage tail sheath proteins were determined to 1.9 and 3.3?? resolution. Despite low sequence identity between these proteins, all of these structures have a similar fold. The crystal structure of the phiKZ tail sheath protein has been fitted into cryo-electron-microscopy reconstructions of the extended tail sheath and of a polysheath. The structural rearrangement of the phiKZ tail sheath contraction was found to be similar to that of phage T4.  相似文献   
99.
100.
The second messenger cyclic diguanylate (c-di-GMP) controls the transition between motile and sessile growth in eubacteria, but little is known about the proteins that sense its concentration. Bioinformatics analyses suggested that PilZ domains bind c-di-GMP and allosterically modulate effector pathways. We have determined a 1.9 A crystal structure of c-di-GMP bound to VCA0042/PlzD, a PilZ domain-containing protein from Vibrio cholerae. Either this protein or another specific PilZ domain-containing protein is required for V. cholerae to efficiently infect mice. VCA0042/PlzD comprises a C-terminal PilZ domain plus an N-terminal domain with a similar beta-barrel fold. C-di-GMP contacts seven of the nine strongly conserved residues in the PilZ domain, including three in a seven-residue long N-terminal loop that undergoes a conformational switch as it wraps around c-di-GMP. This switch brings the PilZ domain into close apposition with the N-terminal domain, forming a new allosteric interaction surface that spans these domains and the c-di-GMP at their interface. The very small size of the N-terminal conformational switch is likely to explain the facile evolutionary diversification of the PilZ domain.  相似文献   
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