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11.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.

Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.

Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).

Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.

Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases.  相似文献   
12.
Hepatic uptake mediated by organic anion transporting polypeptide (OATP) 1B1 and 1B3 can serve as a major elimination pathway for various anionic drugs and as a site of drug-drug interactions (DDIs). This article provides an overview of the in vitro approaches used to predict human hepatic clearance (CLh) and the risk of DDIs involving OATP1Bs. On the basis of the so-called extended clearance concept, in vitro–in vivo extrapolation methods using human hepatocytes as in vitro systems have been used to predict the CLh involving OATP1B-mediated hepatic uptake. CLh can be quantitatively predicted using human donor lots possessing adequate OATP1B activities. The contribution of OATP1Bs to hepatic uptake can be estimated by the relative activity factor, the relative expression factor, or selective inhibitor approaches, which offer generally consistent outcomes. In OATP1B1 inhibition assays, substantial substrate dependency was observed. The time-dependent inhibition of OATP1B1 was also noted and may be a mechanism underlying the in vitro–in vivo differences in the inhibition constant of cyclosporine A. Although it is still challenging to quantitatively predict CLh and DDIs involving OATP1Bs from only preclinical data, understanding the utility and limitation of the current in vitro methods will pave the way for better prediction.  相似文献   
13.
Context The root of Helicteres angustifolia L. (Sterculiaceae) has been used as folk herbal drug to treat cancer, bacterial infections, inflammatory, and flu in China. However, there is no report on its antidiabetic activity.

Objective This study evaluates the antidiabetic activity of ethanol extract from H. angustifolia root.

Materials and methods The promoting effect of H. angustifolia root ethanol extract (25, 50, and 100 μg/mL) on glucose uptake was evaluated using HepG2 cell, differentiated C2C12 myotubes, and differentiated 3T3-L1 adipocytes. The antidiabetic activity of the extract was assessed in vivo using STZ-induced diabetic rats by orally administration of the extract (200 and 400?mg/kg b.w.) once per day for 28 d. Blood glucose, TG, TC, TP, HDL-C, UA, BUN, AST, ALT, insulin, and HOMA-IR were analyzed.

Results The results showed that the extract increased glucose uptake in C2C12 myotubes and 3T3-L1 adipocytes with an IC50 value of 79.95 and 135.96 μg/mL, respectively. And about 12%, 19%, and 10% (p < 0.05) in HepG2 cells when compared with the control at the concentration of 25, 50, and 100 μg/mL, respectively. After 28 days’ treatment with the extract, significant reduction was observed in blood glucose, HOMA-IR, TC, TG, UA, BUN, AST, and ALT levels, while the levels of TP and HDL cholesterol increased.

Discussion and conclusion These results suggest that H. angustifolia root ethanol extract possess potent antidiabetic activity, which is the first report on antidiabetic activity of this plant.  相似文献   
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16.
Purpose: Mouse double-stranded DNA-dependent protein kinase (DNA-PK) activity is heat sensitive. Recovery of heat-inactivated DNA repair activity is a problem after combination therapy with radiation and heat. We investigated the mechanism of recovery of heat-inactivated DNA-PK activity.

Methods: Hybrid cells containing a fragment of human chromosome 8 in scid cells (RD13B2) were used. DNA-PK activity was measured by an in vitro assay. Immunoprecipitation of the nuclear extract was performed with an anti-Ku80 antibody. Proteins co-precipitated with Ku80 were separated by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and detected by Western blotting using anti-heat shock protein (HSP)72 and anti-heat shock cognate protein (HSC)73 antibodies. HSC73 was overexpressed with the pcDNA3.1 vector. Short hairpin (sh)RNA was used to downregulate HSC73 and HSP72.

Results: The activity of heat-inactivated DNA-PK recovered to about 50% of control during an additional incubation at 37?°C after heat treatment at 44?°C for 15?min in the presence of cycloheximide (which inhibits de novo protein synthesis). Maximal recovery was observed within 3?h of incubation at 37?°C after heat treatment. Constitutively expressed HSC73, which folds newly synthesized proteins, reached maximal levels 3?h after heat treatment using a co-immunoprecipitation assay with the Ku80 protein. Inhibiting HSC73, but not HSP72, expression with shRNA decreased the recovery of DNA-PK activity after heat treatment.

Conclusions: These results suggest that de novo protein synthesis is unnecessary for recovery of some heat-inactivated DNA-PK. Rather, it might be reactivated by the molecular chaperone activity of HSC73, but not HSP72.  相似文献   

17.
ABSTRACT

Objective

To investigate primary care physician clinical practice patterns, barriers, and education surrounding pediatric physical activity (PA), and to compare practice patterns by discipline.  相似文献   
18.
BackgroundHip Osteoarthitis (OA) risk is sport-specific and depends on frequency, intensity, and type of mechanic stress the hip is subjected to. This retrospective observational study aims to investigate the safety and performance of Hymovis (HYADD-4) injection, a hexadecyl (C-16) HA-derivative, when used to manage symptomatic hip OA in active middle-aged sportsmen over a 24-month observation period.MethodsThe retrospective analysis included clinical records of active sportsmen, aged between 40 and 65 years, and suffering from symptomatic Kellgren-Lawrence grade II to III hip OA, treated with two (24 mg/3 ml) Hymovis injections, two weeks apart, every 3–4 months, for two years. When available, data on MRI examination were included in the analysis as well as Heidelberg Sports Activity Score (HAS) and Copenhagen Hip and Groin Outcome Score (HAGOS) questionnaires.ResultsThirty patients (56.4 ± 7.3 years) were included in the study, sixteen cyclists and 14 tennis players. For all patients, HAS and most HAGOS scores improved significantly (p < 0.05) at the first control visit (4 months) and further improved over time. For all other scores an important clinical benefit was experienced by more than 50% of participants. No adverse events were recorded.ConclusionTreatment of hip OA in active sportsmen with Hymovis seems a safe and effective approach for the management of OA symptoms, by potentially protecting cartilage and subchondral bone from further damage.  相似文献   
19.
The study aimed to assess the effect of exogenous factors such as surgeon posture, surgical instrument length, fatigue after a night shift, exercise and caffeine consumption on the spatial accuracy of neurosurgical manipulations. For the evaluation and simulation of neurosurgical manipulations, a testing device developed by the authors was used. The experimental results were compared using nonparametric analysis (Wilcoxon test) and multivariate analysis, which was performed using mixed models. The results were considered statistically significant at p < 0.05. The study included 11 first-year neurosurgery residents who met the inclusion criteria. Hand support in the sitting position (Wilcoxon test p value = 0.0033), caffeine consumption (p = 0.0058) and the length of the microsurgical instrument (p = 0.0032) had statistically significant influences on the spatial accuracy of surgical manipulations (univariate analysis). The spatial accuracy did not significantly depend on the type of standing position (Wilcoxon test p value = 0.2860), whether the surgeon was standing/sitting (p = 0.1029), fatigue following a night shift (p = 0.3281), or physical exertion prior to surgery (p = 0.2845).When conducting the multivariate analysis, the spatial accuracy significantly depended on the test subject (p < 0.0001), the use of support during the test (p = 0.0001), and the length of the microsurgical instrument (p = 0.0397). To increase the spatial accuracy of microsurgical manipulations, hand support and shorter tools should be used. Caffeine consumption in high doses should also be avoided prior to surgery.  相似文献   
20.
Introduction: Effective treatment of rheumatoid arthritis (RA) requires suppression of the underlying inflammation. Measurement of such inflammation, the disease activity, is mandatory to target treatment and maximize outcomes. However, this is not as straightforward as it may seem.

Areas covered: The many tools developed to measure disease activity in RA, from composite scores and patient-reported outcomes, to laboratory markers and imaging are discussed, with a focus on their utility in guiding therapy and assessing response. The complex issues in measuring disease activity in RA, whether in clinical trials or normal clinical practice, and in the context of national guidelines and recommendations, available time, and resources are considered.

Expert commentary: The key to effective management of RA is the rapid suppression of inflammation, ideally to remission, with maintenance of such remission. The aim is to prevent disability and maximize quality of life. Central to this is the ability to determine disease activity (potentially open to suppression) as opposed to damage (irreversible). A variety of measures are currently available, allowing better assessment of response to treatment. In the future, the development of predictive biomarkers allowing targeting of drugs may revolutionize this field and render the tools of today redundant.  相似文献   

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