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51.
A series of thiazolopyrimidine derivatives was designed and synthesized as a Leishmania major pteridine reductase 1 (LmPTR1) enzyme inhibitor. Their LmPTR1 inhibitor activities were evaluated using the enzyme produced by Escherichia coli in a recombinant way. The antileishmanial activity of the selected compounds was tested in vitro against Leishmania sp. Additionally, the compounds were evaluated for cytotoxic activity against the murine macrophage cell line RAW 264.7. According to the results, four compounds displayed not only a potent in vitro antileishmanial activity against promastigote forms but also low cytotoxicity. Among them, compound L16 exhibited an antileishmanial activity for both the promastigote and amastigote forms of L. tropica, with IC50 values of 7.5 and 2.69 µM, respectively. In addition, molecular docking studies and molecular dynamics simulations were also carried out in this study. In light of these findings, the compounds provide a new potential scaffold for antileishmanial drug discovery.  相似文献   
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The aim of this study was to develop a novel nanosize drug candidate for cancer therapy. For this purpose, (S)-methyl 2-[(7-hydroxy-2-oxo-4-phenyl-2H-chromen-8-yl)methyleneamino]-3-(1H-indol-3-yl)propanoate (ND3) was synthesized by the condensation reaction of 8-formyl-7-hydroxy-4-phenylcoumarin with l -tryptophan methyl ester. Its controlled release formulation was prepared and characterized by different spectroscopic and imaging methods. The cytotoxic effects of ND3 and its controlled release formulation were evaluated against MCF-7 and A549 cancer cell lines, and it was found that both of them have a toxic effect on cancer cells. For drug design and process development, the molecular docking analysis technique helps to clarify the effects of some DNA-targeted anticancer drugs to determine the interaction mechanisms of these drugs on DNA in a shorter time and at a lower cost. By using the molecular docking analysis and DNA binding assays, the interaction between the synthesized compound and DNA was elucidated and non-binding interactions were also determined. To predict the pharmacokinetics, and thereby accelerate drug discovery, the absorption, distribution, metabolism, excretion and toxicity values of the synthesized compound were determined by in silico methods.  相似文献   
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Both genetics and physical activity (PA) contribute to bone mineral density (BMD), but it is unknown if the benefits of physical activity on childhood bone accretion depend on genetic risk. We, therefore, aimed to determine if PA influenced the effect of bone fragility genetic variants on BMD in childhood. Our sample comprised US children of European ancestry enrolled in the Bone Mineral Density in Childhood Study (N = 918, aged 5 to 19 years, and 52.4% female). We used a questionnaire to estimate hours per day spent in total, high‐, and low‐impact PA. We calculated a BMD genetic score (% BMD lowering alleles) using adult genome‐wide association study (GWAS)‐implicated BMD variants. We used dual‐energy X‐ray absorptiometry to estimate femoral neck, total hip, and spine areal‐BMD and total body less head (TBLH) bone mineral content (BMC) Z‐scores. The BMD genetic score was negatively associated with each bone Z‐score (eg, TBLH‐BMC: estimate = –0.03, p = 1.3 × 10?6). Total PA was positively associated with bone Z‐scores; these associations were driven by time spent in high‐impact PA (eg, TBLH‐BMC: estimate = 0.05, p = 4.0 × 10?10) and were observed even for children with lower than average bone Z‐scores. We found no evidence of PA‐adult genetic score interactions (p interaction > 0.05) at any skeletal site, and there was no evidence of PA‐genetic score–Tanner stage interactions at any skeletal site (p interaction > 0.05). However, exploratory analyses at the individual variant level revealed that PA statistically interacted with rs2887571 (ERC1/WNT5B) to influence TBLH‐BMC in males (p interaction = 7.1 × 10?5), where PA was associated with higher TBLH‐BMC Z‐score among the BMD‐lowering allele carriers (rs2887571 AA homozygotes: estimate = 0.08 [95% CI 0.06, 0.11], p = 2.7 × 10?9). In conclusion, the beneficial effect of PA on bone, especially high‐impact PA, applies to the average child and those genetically predisposed to lower adult BMD (based on GWAS‐implicated BMD variants). Independent replication of our exploratory individual variant findings is warranted. © 2016 American Society for Bone and Mineral Research.  相似文献   
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Objective To investigate the effects of chronic renal failure (CRF) on the distal femoral cartilage thickness by using ultrasonography and to determine the relationship between cartilage thickness and certain disease-related parameters. Design Fifty-seven CRF patients (41 male and 16 female) (mean [SD] age, 44.7 [12.1] years) and 60 healthy controls (41 male and 19 female) (mean [SD] age, 43.5 [13.3] years) were enrolled in this study. Demographic and clinical characteristics were recorded. Cartilage thickness measurements were taken from the medial and lateral condyles, and intercondylar areas of both knees. Results Groups were similar in terms of age, weight, height, body mass index and gender (all p>0.05). The mean cartilage thickness was found to be less in CRF patients than in controls (statistically significant for medial condyles and intercondylar areas both in right and the left knees [all p<0.05]). Cartilage thickness showed no correlation with eGFR, and with the levels of serum urea, creatinine, calcium, magnesium, phosphor, hemoglobin, uric acid and as well as steroid use (all p>0.05) in CRF patients. Conclusion In the light of our findings, we imply that patients with CRF have thinner femoral cartilage than healthy controls. This result may support the view that patients with CRF are at increased risk for developing early knee osteoarthritis. Last but not least, clinicians should be aware of the importance of rehabilitation strategies aimed at decreasing onset and progression of knee osteoarthritis in patients with CRF.  相似文献   
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Scarce data exist regarding costs of pediatric heart failure-related hospitalizations (HFRH) or how costs have changed over time. Pediatric HFRH costs, due to advances in management, will have increased significantly over time. A retrospective analysis of Healthcare Cost and Utilization Project Kids’ Inpatient Database was performed on all pediatric HFRH. Inflation-adjusted charges are used as a proxy for cost. There were a total of 33,189 HFRH captured from 2000 to 2009. Median charges per HFRH rose from $35,079 in 2000 to $72,087 in 2009 (p < 0.0001). The greatest median charges were incurred in patients on extracorporeal membrane oxygenation ($442,134 vs $53,998) or ventricular assist devices ($462,647 vs $55,151). Comorbidities, including sepsis ($207,511 vs $48,995), renal failure ($180,624 vs $52,812), stroke ($198,260 vs $54,974) and respiratory failure ($146,200 vs $48,797), were associated with greater charges (p < 0.0001). Comorbidities and use of mechanical support increased over time. After adjusting for these factors, later year remained associated with greater median charges per HFRH (p < 0.0001). From 2000 to 2009, there has been an almost twofold increase in pediatric HFRH charges, after adjustment for inflation. Although comorbidities and use of mechanical support account for some of this increase, later year remained independently associated with greater charges. Further study is needed to understand potential factors driving these higher costs over time and to identify more cost-effective therapies in this population.  相似文献   
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BACKGROUND: Use of effective scolicidal agents during puncture, aspiration or injection of a scolicidal agent and reaspiration (PAIR) and surgery for hydatid cysts are essential to reduce the recurrence rate. In this in vitro study, we tried to determine the scolicidal property of a new agent, octenidine dihydrochloride, and of various agents in different concentrations and exposure times. MATERIAL AND METHODS: Echinococcus granulosus protoscoleces were obtained from six patients with liver (n=3) and lung (n=3) hydatid cysts. Various concentrations of octenidine dihydrochloride (0.1%, 0.01% and 0.001% diluted form), povidone iodine (10%, 1% and 0.1% diluted) and 20% saline were used in this study. Viability of protoscoleces was determined with dye-uptake (0.1% eosin) and flame cell activity. RESULTS: Octenidine dihydrochloride 0.1% had strong scolicidal effect in 15 min and octenidine dihydrochloride 0.01% in 30 min. Sixty percent of protoscoleces lost viability at 5 min with octenidine dihydrochloride 0.1%. Viability ratio decreased to 20% at 10 min, and all of them died at 15 min. Povidone iodine 10% and 1% had strong scolicidal effects after 15- and 30 min of exposure, respectively. Saline 20% killed all the protoscoleces in 30-min exposure. CONCLUSION: Because of the rapid and strong scolocidal effectiveness of octenidine dihydrochloride on protoscoleces, it may be used as a scolocidal agent during both perioperative and in the PAIR method.  相似文献   
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