The present study was designed to identify the changes in microvesicle-dipeptidyl peptidase-IV (DPP IV) levels in human urine and serum, and to determine whether there were correlations with the severity of diabetic kidney disease (DKD). A total of 127 patients with type 2 diabetes mellitus (T2DM) were divided into three groups according to the urinary albumin/ creatinine ratio (UACR): microalbuminuria group (n = 50); macroalbuminuria group (n = 34) and normoalbuminuria group (n = 43), and 34 age-and sex-matched non-diabetic healthy subjects were selected as controls. Microvesicle-bound DPP IV and free urinary DPP IV were separated by a filtra-centrifugation method. The total microvesicles were captured by a specific monoclonal antibody, AD-1. DPP IV activity was determined by measuring the cleavage of chromogenic free 4-nitroaniline from Gly-Pro-p-nitroanilide at 405 nm with an ELISA plate reader. DPP IV protein levels were determined by ELISA and Western blot. Our results showed that the microvesicle-bound type was the major form of DPP IV in urine; the urinary microvesicle-DPP IV excretion of each T2DM group was significantly higher compared with controls. The urinary microvesicle-DPP IV level was positively correlated with UACR in patients with T2DM. These findings suggest that the urinary level of microvesicle-bound DPP IV is associated with the severity of DKD.
1. Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of lightlevel geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. 2. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta-analyses did not evaluate unpublished data and impact of multiple life-history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially.
To find the right conditions to isolate natively expressed antimicrobial peptides from a wide range of different microorganisms can be a challenge. Here, we exploited a heterologous expression system to produce and characterize several novel lantibiotics. We identified 54 novel putative class I and class II lantibiotics after inspecting all publicly available prokaryotic genomes using the in-house developed mining tool BAGEL3. The genes encoding these new lantibiotics fused to the nisin leader peptide gene sequence were synthesized, and the constructs were plugged into the nisin expression and modification system. Using this approach 30 peptides could be expressed, 27 of which were dehydrated by NisBC on at least 1 predicted position. Good antimicrobial activity against several pathogenic bacteria could be demonstrated for 5 novel heterologously modified lantibiotics. Lantibiotics from Corynebacterium lipophiloflavum DSM 44291 and Streptococcus agalactiae ATCC 13813, named flavucin and agalacticin, respectively, were fully modified and displayed high antimicrobial activity. The efficiency of functional expression was significantly enhanced when we made use of the native nisin leader cleavage site, instead of an artificial factor Xa site. Thus, we describe an efficient way for heterologous production of active lantibiotics, facilitating a rapid identification of promising molecules.
microRNAs (miRNAs) are small noncoding RNAs that regulate genes and contribute to many kinds of human diseases, including cancer. Two miRNAs, miR-511 and miR-1297, were investigated for a possible role in adenocarcinoma based on predicted binding sites for the TRIB2 oncogene by microRNA analysis software, and the pcDNA-GFP-TRIB2–3′UTR vector was constructed to investigate the interaction between TRIB2 and miR-511/1297 in the adenocarcinoma cell line A549. Green fluorescent protein (GFP) expression was estimated by fluorescence microscopy and flow cytometry after A549 cells were co-transfected with miR-511 (or miR-1297) and pcDNA-GFP-TRIB2–3′UTR vector. The expression of GFP in the miR-511- and miR-1297-treated cells was significantly downregulated in contrast with the negative-control (NC) miRNA-treated cells. The decreased expression of TRIB2 was further detected after miR-511 (or miR-1297) treatment by western blotting. The MTT test showed inhibition of A549 cell proliferation and Annexin V-FITC/PI dual staining showed increased apoptosis in the miR-511- and miR-1297-treated cells compared to the NC cultures. A transcription factor downstream of TRIB2, the CCAAT/enhancer-binding protein alpha (C/EBPα), was expression at higher levels after miR-511 (or miR-1297) decreasing TRIB2 expression. Our results illustrate that miR-511 and miR-1297 act as tumor suppressor genes, which could suppress A549 cell proliferation in vitro and in vivo by suppressing TRIB2 and further increasing C/EBPα expression.
The fidelity of synaptic transmission depends on the integrity of the protein machinery at the synapse. Unfolded synaptic proteins undergo refolding or degradation in order to maintain synaptic proteostasis and preserve synaptic function, and buildup of unfolded/toxic proteins leads to neuronal dysfunction. Many molecular chaperones contribute to proteostasis, but one in particular, cysteine string protein (CSPα), is critical for proteostasis at the synapse. In this study we report that exported vesicles from neurons contain CSPα. Extracellular vesicles (EV’s) have been implicated in a wide range of functions. However, the functional significance of neural EV’s remains to be established. Here we demonstrate that co-expression of CSPα with the disease-associated proteins, polyglutamine expanded protein 72Q huntingtinex°n1 or superoxide dismutase-1 (SOD-1G93A) leads to the cellular export of both 72Q huntingtinex°n1 and SOD-1G93A via EV’s. In contrast, the inactive CSPαHPD-AAA mutant does not facilitate elimination of misfolded proteins. Furthermore, CSPα-mediated export of 72Q huntingtinex°n1 is reduced by the polyphenol, resveratrol. Our results indicate that by assisting local lysosome/proteasome processes, CSPα-mediated removal of toxic proteins via EVs plays a central role in synaptic proteostasis and CSPα thus represents a potential therapeutic target for neurodegenerative diseases.
Hygrocins are naphthoquinone ansamycins with significant antitumor activities. Here, we report the identification and characterization of the hygrocin biosynthetic gene cluster (hgc) in Streptomyces sp. LZ35. A biosynthetic pathway is proposed based on bioinformatics analysis of the hgc genes and intermediates accumulated in selected gene disruption mutants. One of the steps during the biosynthesis of hygrocins is a Baeyer–Villiger oxidation between C5 and C6, catalyzed by luciferase- like monooxygenase homologue Hgc3. Hgc3 represents the founding member of a previously uncharacterized family of enzymes acting as Baeyer–Villiger monooxygenases.
Image-based noninvasive fractional flow reserve (FFR) is an emergent approach to determine the functional relevance of coronary stenoses. The present work aimed to determine the feasibility of using a method based on coronary computed tomography angiography (CCTA) and reduced-order models (0D-1D) for the evaluation of coronary stenoses. The reduced-order methodology (cFFR RO ) was kept as simple as possible and did not include pressure drop or stenosis models. The geometry definition was incorporated into the physical model used to solve coronary flow and pressure. cFFRRO was assessed on a virtual cohort of 30 coronary artery stenoses in 25 vessels and compared with a standard approach based on 3D computational fluid dynamics (cFFR 3D ). In this proof-of-concept study, we sought to investigate the influence of geometry and boundary conditions on the agreement between both methods. Performance on a per-vessel level showed a good correlation between both methods (Pearson's product-moment R = 0.885, P < 0.01), when using cFFR 3D as the reference standard. The 95% limits of agreement were −0.116 and 0.08, and the mean bias was −0.018 (SD = 0.05). Our results suggest no appreciable difference between cFFR RO and cFFR 3D with respect to lesion length and/or aspect ratio. At a fixed aspect ratio, however, stenosis severity and shape appeared to be the most critical factors accounting for differences in both methods. Despite the assumptions inherent to the 1D formulation, asymmetry did not seem to affect the agreement.The choice of boundary conditions is critical in obtaining a functionally significant drop in pressure. Our initial data suggest that this approach may be part of a broader risk assessment strategy aimed at increasing the diagnostic yield of cardiac catheterisation for in-hospital evaluation of haemodynamically significant stenoses. KEYWORDSboundary conditions, coronary stenosis severity, shape and asymmetry, non-invasive fractional flow reserve, reduced-order model
Six hygrocins, polyketides of ansamycin class, were isolated from the gdmAI-disrupted Streptomyces sp. LZ35. The planar structure of hygrocins C-E (1-3) was determined by one-dimensional and two-dimensional NMR spectroscopy and high-resolution mass spectrometry. They are derivatives of hygrocin A but differ in the configuration at C-2 and the orientation of the C-3,4 double bond. Hygrocin F(4) and G(5) were shown to be isomers of hygrocin C (1) and B (6), respectively, due to the different alkyl oxygen participating in the macrolide ester linkage. Hygrocins C, D, and F were found to be toxic to human breast cancer MDA-MB-431 cells (IC50 = 0.5, 3.0, and 3.3 μM, respectively) and prostate cancer PC3 cells (IC50 = 1.9, 5.0, and 4.5 μM, respectively), while hygrocins B, E, and G were inactive.
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