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781.
782.
It is of interest to evaluate the clinical effectiveness and safety of vildagliptin as monotherapy and combination therapy of vildagliptin and metformin for the management of type 2 diabetes mellitus (T2DM) patients in Indian settings. The study included patients with T2DM (aged >18 years) receiving vildagliptin monotherapy and vildagliptin in combination with metformin therapy of various strengths. Data related to demographics, risk factors, medical history, glycated hemoglobin (HbA1c) levels, and medical therapies were retrieved from medical records. Out of 9678 patients (median age, 52.0 years), 59.1% were men. A combination of vildagliptin and metformin (50/500 mg) was the most commonly used therapy (54.8%), and the median duration of therapy was 24.0 months. The predominant reason for selecting vildagliptin therapy was to improve HbA1c levels (87.8%). A total of 87.5% of patients required dosage up-titration. Vildagliptin therapy was used in patients with T2DM and associated complications (peripheral neuropathy, CAD, nephropathy, retinopathy, autonomous neuropathy, stroke/TIA, and peripheral artery disease). Among 5175 patients who experienced body weight changes, a majority of patients showed a loss of weight (68.6%). The target glycemic control was achieved in 95.3% of patients. The mean HbA1c levels were significantly decreased post-treatment (mean change: 1.34%; p<0.001). Adverse events were reported in 0.4% of patients. Physicians rated the majority of patients as good to excellent on the global evaluation of efficacy and tolerability scale (98.9%, each). Vildagliptin as monotherapy and combination therapy of vildagliptin and metformin was an effective therapy in reducing HbA1c helps in achieving target glycemic control, and was well tolerated in Indian patients with T2DM continuum.  相似文献   
783.
Molecular Biology Reports - Pro-inflammatory cytokine IL-17A modulates the expression of Akt in bleomycin (BLM) administered alveolar basal epithelial cells, the mechanism behind which remains...  相似文献   
784.
Tumor necrosis factor-α is an important pro-inflammatory cytokine having a key role in hosts defensive process of immune systems and its over expression led to a diverse range of inflammatory diseases such as Rheumatoid arthritis, Cronh’s disease, psoriasis, etc. This paper describes our medicinal chemistry efforts on imidazo[1,2-b]pyridazine scaffold: design, synthesis and biological evaluation. By the introducing sulfonamide functionality at 3 positions and substituting 6 positions with (hetero)-aryl groups’, a small library of compounds was prepared. All synthesized compounds were screened for lipopolysaccharide (LPS) mediated TNF-α production inhibitory activity. Biological data revealed that the majority of the compounds of this series showed moderate to potent TNF-α production inhibitory activity. Compound 5u and 5v are the most potent compounds from the series with activity of IC50?=?0.5?µM and 0.3?µM respectively. A short SAR demonstrates that 3-sulfonyl-4-arylpiperidine-4-carbonitrile moiety on imidazo[1,2-b]pyridazine showed better activity compared to the 3-(4-aryllpiperazin-1-yl) sulfonyl) in hPBMC assay. The molecular modeling studies revealed that the potent TNF-α production inhibitory activity 5v due to the extra stability of complex because of an extra pi-pi (π-π) stacking, hydrogen-bonding interactions.  相似文献   
785.
The concept of using microalgae as an alternative renewable source of biofuel has gained much importance in recent years. However, its commercial feasibility is still an area of concern for researchers. Unraveling the fatty acid metabolic pathway and understanding structural features of various key enzymes regulating the process will provide valuable insights to target microalgae for augmented oil content. FabH (β-ketoacyl-acyl carrier protein synthase; KAS III) is a condensing enzyme catalyzing the initial elongation step of type II fatty acid biosynthetic process and acyl carrier protein (ACP) facilitates the shuttling of the fatty acyl intermediates to the active site of the respective enzymes in the pathway. In the present study, a reliable three-dimensional structure of FabH from Chlorella variabilis, an oleaginous green microalga was modeled and subsequently the key residues involved in substrate binding were determined by employing protein–protein docking and molecular dynamics (MD) simulation protocols. The FabH-ACP complex having the lowest docking energy score showed the binding of ACP to the electropositive FabH surface with strong hydrogen bond interactions. The MD simulation results indicated that the substrate-complexed FabH adopted a more stable conformation than the free enzyme. Further, the FabH structure retained its stability throughout the simulation although noticeable displacements were observed in the loop regions. Molecular simulation studies suggested the importance of crucial hydrogen bonding of the conserved Arg91 of FabH with Glu53 and Asp56 of ACP for exhibiting high affinity between the enzyme and substrate. The molecular modeling results are consistent with available experimental results on the flexibility of FabH and the present study provides first in silico insights into the structural and dynamical aspect of catalytic mechanism of FabH, which could be used for further site-specific mutagenic experiments to develop engineered high oil-yielding microalgal strains for biofuel production.  相似文献   
786.

Purpose

Simulation plays a critical role in the design of products, materials, and manufacturing processes. However, there are gaps in the simulation tools used by industry to provide reliable results from which effective decisions can be made about environmental impacts at different stages of product life cycle. A holistic and systems approach to predicting impacts via sustainable manufacturing planning and simulation (SMPS) is presented in an effort to incorporate sustainability aspects across a product life cycle.

Methods

Increasingly, simulation is replacing physical tests to ensure product reliability and quality, thereby facilitating steady reductions in design and manufacturing cycles. For SMPS, we propose to extend an earlier framework developed in the Systems Integration for Manufacturing Applications (SIMA) program at the National Institute of Standards and Technology. SMPS framework has four phases, viz. design product, engineer manufacturing, engineer production system, and produce products. Each phase has its inputs, outputs, phase level activities, and sustainability-related data, metrics and tools.

Results and discussion

An automotive manufacturing scenario that highlights the potential of utilizing SMPS framework to facilitate decision making across different phases of product life cycle is presented. Various research opportunities are discussed for the SMPS framework and corresponding information models.

Conclusions

The SMPS framework built on the SIMA model has potential in aiding sustainable product development.  相似文献   
787.
Dimethylsulfoxide (DMSO)‐quenched hydrogen/deuterium (H/D)‐exchange is a powerful method to characterize the H/D‐exchange behaviors of proteins and protein assemblies, and it is potentially useful for investigating non‐protected fast‐exchanging amide protons in the unfolded state. However, the method has not been used for studies on fully unfolded proteins in a concentrated denaturant or protein solutions at high salt concentrations. In all of the current DMSO‐quenched H/D‐exchange studies of proteins so far reported, lyophilization was used to remove D2O from the protein solution, and the lyophilized protein was dissolved in the DMSO solution to quench the H/D exchange reactions and to measure the amide proton signals by two‐dimensional nuclear magnetic resonance (2D NMR) spectra. The denaturants or salts remaining after lyophilization thus prevent the measurement of good NMR spectra. In this article, we report that the use of spin desalting columns is a very effective alternative to lyophilization for the medium exchange from the D2O buffer to the DMSO solution. We show that the medium exchange by a spin desalting column takes only about 10 min in contrast to an overnight length of time required for lyophilization, and that the use of spin desalting columns has made it possible to monitor the H/D‐exchange behavior of a fully unfolded protein in a concentrated denaturant. We report the results of unfolded ubiquitin in 6.0M guanidinium chloride.  相似文献   
788.
789.

Background

Our objective was to develop and validate a multi-feature nuclear score based on image analysis of direct DNA staining, and to test its association with field effects and subsequent detection of prostate cancer (PCa) in benign biopsies.

Methods

Tissue sections from 39 prostatectomies were Feulgen-stained and digitally scanned (400×), providing maps of DNA content per pixel. PCa and benign epithelial nuclei were randomly selected for measurement of 52 basic morphometric features. Logistic regression models discriminating benign from PCa nuclei, and benign from malignant nuclear populations, were built and cross-validated by AUC analysis. Nuclear populations were randomly collected <1 mm or >5 mm from cancer foci, and from cancer-free prostates, HGPIN, and PCa Gleason grade 3–5. Nuclei also were collected from negative biopsy subjects who had a subsequent diagnosis of PCa and age-matched cancer-free controls (20 pairs).

Results

A multi-feature nuclear score discriminated cancer from benign cell populations with AUCs of 0.91 and 0.79, respectively, in training and validation sets of patients. In prostatectomy samples, both nuclear- and population-level models revealed cancer-like features in benign nuclei adjacent to PCa, compared to nuclei that were more distant or from PCa-free glands. In negative biopsies, a validated model with 5 variance features yielded significantly higher scores in cases than controls (P = 0.026).

Conclusions

A multifeature nuclear morphometric score, obtained by automated digital analysis, was validated for discrimination of benign from cancer nuclei. This score demonstrated field effects in benign epithelial nuclei at varying distance from PCa lesions, and was associated with subsequent PCa detection in negative biopsies.

Impact

This nuclear score shows promise as a risk predictor among men with negative biopsies and as an intermediate biomarker in Phase II chemoprevention trials. The results also suggest that subvisual disturbances in nuclear structure precede the development of pre-neoplastic lesions.  相似文献   
790.
Plant Molecular Biology Reporter - In plants, Lipoxygenase (LOX) genes play crucial roles in tolerance to abiotic as well as biotic stress. Although they have been characterized in various plants,...  相似文献   
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