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681.
682.

Introduction

Type 2 diabetes (T2D) is an independent risk factor in the development of cardiovascular disease. However, there are significant limitations in the detection of the metabolic disturbances in hyperglycemia that lead to vascular dysfunction.

Objectives

The goals of the study were: (i) to identify circulating metabolites discriminating T2D and normoglycemia, and (ii) to assess phenotypic correlations of identified metabolites with other cardiometabolic risk traits (CMTs).

Methods

We have generated global and targeted metabolomic profiles using AB Sciex TripleTOF 5600 and Thermo Scientific Q Exactive Plus using serum samples of patients and healthy controls from a Punjabi population from India.

Results

In global profiling, we identified eight unknown molecules that currently do not match to any spectra in public databases. Additionally, serum levels of pyroglutamate, imidazole-4-acetate, tyramine-O-sulphate and 2,3-diphosphoglycerate were significantly elevated (2–5 fold) and betaine-aldehyde was reduced (fourfold) in patients. In targeted screening of amino acids and sugars, increased concentrations of serine, inositol, and threonine strongly correlated with T2D in both genders, while N-acetyl-l-alanine was reduced (58 fold) in men and glutamine was increased (fourfold) in women. Using random forest and ROC (AUC) analyses, we further cross-validated the predictive abilities of these molecules. Inositol, serine and threonine were among the top informative biomarkers in both genders while N-acetyl-l-alanine was highly confined to men.

Conclusions

Our study has identified several metabolites whose concentrations were altered in T2D. Although further study is needed in larger datasets, the identified metabolites (unknown or known) point towards shared etiological pathways underlie diabetes and vascular disease which can be targeted for potential therapeutics or biomarkers discovery.
  相似文献   
683.

Aim

To systematically review currently available cardiac shock-wave therapy (CSWT) studies in humans and perform meta-analysis regarding anti-anginal efficacy of CSWT.

Methods

The Cochrane Controlled Trials Register, Medline, Medscape, Research Gate, Science Direct, and Web of Science databases were explored. In total 39 studies evaluating the efficacy of CSWT in patients with stable angina were identified including single arm, non- and randomized trials. Information on study design, subject’s characteristics, clinical data and endpoints were obtained. Assessment of publication risk of bias was performed and heterogeneity across the studies was calculated by using random effects model.

Results

Totally, 1189 patients were included in 39 reviewed studies, with 1006 patients treated with CSWT. The largest patient sample of single arm study consisted of 111 patients. All selected studies demonstrated significant improvement in subjective measures of angina symptoms and/or quality of life, in the majority of studies left ventricular function and myocardial perfusion improved. In 12 controlled studies with 483 patients included (183 controls) angina class, Seattle Angina Questionnaire (SAQ) score, nitrates consumption were significantly improved after the treatment.In 593 participants across 22 studies the exercise capacity was significantly improved after CSWT, as compared with the baseline values (in meta-analysis standardized mean difference SMD?=??0.74; 95% CI, ?0.97 to ?0.5; p?<?0.001).

Conclusions

Systematic review of CSWT studies in stable coronary artery disease (CAD) demonstrated consistent improvement of clinical variables. Meta-analysis showed a moderate improvement of exercise capacity.Overall, CSWT is a promising non-invasive option for patients with end-stage CAD, but evidence is limited to small sample single-center studies. Multi-center adequately powered randomised double blind studies are warranted.
  相似文献   
684.
Comparison of the stability of five plant peroxidases (horseradish, royal palm tree leaf, soybean, and cationic and anionic peanut peroxidases) was carried out under acidic conditions favorable for synthesis of polyelectrolyte complexes of polyaniline (PANI). It demonstrates that palm tree peroxidase has the highest stability. Using this peroxidase as a catalyst, the enzymatic synthesis of polyelectrolyte complexes of PANI and poly(2-acrylamido-3-methyl-1-propanesulfonic acid) (PAMPS) was developed. The template polymerization of aniline was carried out in aqueous buffer at pH 2.8. Varying the concentrations of aniline, PAMPS, and hydrogen peroxide as reagents, favorable conditions for production of PANI were determined. UV-vis-NIR absorption and EPR demonstrated that PAMPS and PANI formed the electroactive complex similar to PANI doped traditionally using low molecular weight sulfonic acids. The effect of pH on conformational variability of the complex was evaluated by UV-vis spectroscopy. Atomic force microscopy showed that a size of the particles of the PANI-PAMPS complexes varied between 10 and 25 nm, depending on a concentration of PAMPS in the complex. The dc conductivity of the complexes depends also on the content of PAMPS, the higher conductivity being for the complexes containing the lower content of the polymeric template.  相似文献   
685.
We suggest an annotation strategy for genes encoded by retroviruses and transposable elements (RETRA genes) based on a set of marker protein domains. Usually RETRA genes are masked in vertebrate genomes prior to the application of automated gene prediction pipelines under the assumption that they provide no selective advantage to the host. Yet, we show that about 1000 genes in four vertebrate gene sets analyzed contain at least one RETRA gene marker domain. Using the conservation of genomic neighborhood (synteny), we were able to discriminate between RETRA genes with putative functionality in the vertebrates and those that probably function only in the context of mobile elements. We identified 35 such genes in human, along with their corresponding mouse and rat orthologs; which included almost all known human genes with similarity to mobile elements. The results also imply that the vast majority of the remaining RETRA genes in current gene sets are unlikely to encode vertebrate functions. To automatically annotate RETRA genes in other vertebrate genomes, we provide as a tool a set of marker protein domains and a manually refined list of domesticated or ancestral RETRA genes for rescuing genes with vertebrate functions.  相似文献   
686.
The synthesis of potent 4-aryl methoxypiperidinol inhibitors of the dopamine transporter is described. Symmetrical para substituents of the benzene rings are important for high potency in binding to the dopamine transporter. 4-[Bis(4-fluorophenyl) methoxy]-1-methylpiperidine has an IC50 of 22.1+/-5.73 nM and increases locomotor activity in mice.  相似文献   
687.
Little is known about the molecular mechanisms of learned and innate fear. We have identified stathmin, an inhibitor of microtubule formation, as highly expressed in the lateral nucleus (LA) of the amygdala as well as in the thalamic and cortical structures that send information to the LA about the conditioned (learned fear) and unconditioned stimuli (innate fear). Whole-cell recordings from amygdala slices that are isolated from stathmin knockout mice show deficits in spike-timing-dependent long-term potentiation (LTP). The knockout mice also exhibit decreased memory in amygdala-dependent fear conditioning and fail to recognize danger in innately aversive environments. By contrast, these mice do not show deficits in the water maze, a spatial task dependent on the hippocampus, where stathmin is not normally expressed. We therefore conclude that stathmin is required for the induction of LTP in afferent inputs to the amygdala and is essential in regulating both innate and learned fear.  相似文献   
688.
Sinorhizobium meliloti was isolated from nodules and soil from western Tajikistan, a center of diversity of the host plants (Medicago, Melilotus, and Trigonella species). There was evidence of recombination, but significant disequilibrium, between and within the chromosome and megaplasmids. The most frequent alleles matched those in the published genome sequence.  相似文献   
689.
Proteolytic digestion of the phenol-water extraction product of the fish pathogen Flavobacterium columnare afforded a mixture of glycopeptides in which the oligosaccharide moiety was an unusual hexasaccharide composed of 4-O-methyl-2-acetamido-2-deoxy-D-glucuronic acid (GlcNAcA), D-glucuronic acid (D-GlcA), 2,3-di-O-acetyl-D-xylose (D-Xyl), 2-O-methyl-D-glucuronic acid (D-GlcA), D-mannose (D-Man), and 2-O-methyl-L-rhamnose (L-Rha). By the application of high-resolution 1D and 2D NMR, mass spectrometry, and chemical analysis, the hexasaccharide structure was determined to be: [carbohydrate structure--see text] where all monosaccharides have the D-configuration except for 2-O-methyl-L-rhamnose; and were in the pyranose form. Only one carbohydrate structure was found. The peptide part was represented by tri- to hepta-peptides with a minimal common tripeptide fragment Asp-Ser-Ala, extended with Ala and Val.  相似文献   
690.
The chemical structures of polysaccharides and LPS core oligosaccharides, isolated from various Gram-negative marine bacteria from the genera Pseudoalteromonas and Shewanella belonging to the Alteromonadaceae family and gamma-subclass of Proteobacteria, are reviewed. The polysaccharides are distinguished by the acidic character (e.g., due to the presence of hexuronic and aldulosonic acids and their derivatives) and the occurrence of unusual sugars, including N-acyl derivatives of 6-deoxyamino sugars, such as N-acetyl-D-quinovosamine, N-acetyl-L-fucosamine and N-acetyl-6-deoxy-L-talosamine, and higher sugars like 2,6-dideoxy-2-acetamido-4-C-(3'-carboxamide-2',2'-dihydroxypropyl)-D-galactopyranose (shewanellose). Many constituent sugars have various uncommon non-sugar substituents, such as alanine, formic, lactic and hydroxybutyric acids, sulfate, phosphate, and 2-aminopropane-1,3-diol.  相似文献   
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