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81.
Aim of this study was to estimate how knee osteoarthritis (OA) affects the shape of femoral condyles by comparing the radiuses of condylar curves between healthy and OA knees. Seventeen female and five male patients with established diagnosis of knee OA were included in the study. Radiuses of medial and lateral condylar curves were calculated from the side view knee X-ray by original mathematical equation and compared to referent values of healthy knees, after adjusting to body height. The average radiuses of condylar curves were between 52.6 +/- 6.2 and 17.6 +/- 3.5 mm medially, and between 43.3 +/- 8.4 and 15.4 +/- 3.7 mm laterally for 0 degrees and 90 degrees femoral flexion contact points, respectively The OA knees had longer curve radiuses medially and laterally at 0 degrees, 10 degrees, and 20 degrees femoral flexion contact points in comparison to the healthy sample (P < 0.001; t-test). Our results suggest that the shape of the femoral condyles in OA knees is changed. It should be aware not only in researching of OA etiology, but also in designing of knee endoprostheses, in a manner to achieve better individual sizing.  相似文献   
82.

Background  

Inflammatory reactions occurring in the brain after ischemia may contribute to secondary damage. In the present study, effects of minocycline, an anti-inflammatory agent, alone or in combination with mild hypothermia on focal embolic cerebral ischemia have been examined.  相似文献   
83.
Raza  Shahbaz  Mohsin  Mashkoor  Madni  Waqas Ahmed  Sarwar  Fatima  Saqib  Muhammad  Aslam  Bilal 《EcoHealth》2017,14(1):182-186
EcoHealth - We investigated wild migratory birds faecal swabs for extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-K. pneumoniae) from wetland habitats in Pakistan. ESBL-K....  相似文献   
84.
DNA photolyase is perhaps the most ancient and direct arsenal in curing the UV-induced dimers formed in the microbial genome. Out of two cofactors of the enzyme, catalytic and light harvesting, differences in the latter have provided basis for categorizing photolyases of prokaryotes as folate and deazaflavin types. In the present study, the homology modeling of DNA photolyase of Enterococcus faecalis was undertaken. The predicted models were structurally compared with the crystal structure coordinates of photolyases from Escherichia coli (folate type) and Anacystis nidulans (deazaflavin type). Discrepancies present in the multiple sequence alignment and tertiary structures, particularly at the light harvesting cofactor (methenyltetrahydrofolic acid, MTHF; 8-hydroxy-5-deazaflavin, 8-HDF) binding sites indicated the mechanistic nature of enterococcal photolyase. Concisely, despite the greater holistic homology with folate-type photolyase, enterococcal photolyase was characterized as deazaflavin-type. The presence of 8-HDF binding sites and groove architecture of substrate binding sites were also found supportive in this regard. The inter cofactor distance and/or orientation also implied to the efficient energy transfer in photolyase of Enterococcus in comparison with E. coli. In addition, we observed relatively high protein deformability in the enterococcal genome, which may favors the repair action of photolyase. The findings are expected to provide molecular insights into the difference in sunlight inactivation rate of two important fecal contamination indicators, namely Enterococcus and E. coli.  相似文献   
85.
The production of mycotoxins from Fusarium species has been demonstrated in isolates cultured from patients suffering from keratomycosis. The method employed a combination of thin-layer chromatography directly performed on gel plugs taken from the growth medium, cartridge column chromatography, silylation and gas chromatography on a non-polar stationary phase capillary column linked to mass spectrometry. The sensitivities of detection obtained for a signal-to-noise ratio of 33:1, were 200 pg for single stage GC-MS and 20 pg using tandem GC-MS-MS. Two mycotoxins, diacetoxyscirpenol and T-2 toxin were identified in three cultures.  相似文献   
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Derivatization of fullerenes to polyhydroxylated fullerenes, i.e., fullerenols (FLU), dramatically decreases their toxicity and has been reported to enhance the solubility as well as cellular permeability. In this paper, we report synthesis of FLU as nanocarrier and subsequent chemical conjugation of Methotrexate (MTX) to FLU with a serum-stable and intracellularly hydrolysable ester bond between FLU and MTX. The conjugate was characterized for physiochemical attributes, micromeritics, drug-loading, and drug-release and evaluated for cancer cell-toxicity, cellular-uptake, hemocompatibility, protein binding, and pharmacokinetics. The developed hemocompatible FL-MTX offered lower protein binding vis-à-vis naïve drug and substantially higher drug loading. The conjugate offered pH-dependent release of 38.20?±?1.19% at systemic pH and 85.67?±?3.39% at the cancer cell pH. FLU-MTX-treated cells showed significant reduction in IC50 value vis-à-vis the cells treated with pure MTX. Analogously, the results from confocal scanning laser microscopy also confirmed the easy access of the dye-tagged FLU-MTX conjugate to the cell interiors. In pharmacokinetics, the AUC of MTX was enhanced by approx. 6.15 times and plasma half-life was enhanced by 2.45 times, after parenteral administration of single equivalent dose in rodents. FLU-MTX offered enhanced availability of drug to the biological system, meanwhile improved the cancer-cell cytotoxicity, sustained the effective plasma drug concentrations, and offered substantial compatibility to erythrocytes.  相似文献   
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89.
Humans have been exposed to many environmental challenges since their evolutionary origins in Africa and subsequent migrations to the rest of the world. A severe environmental challenge to human migrants was hypoxia caused by low barometric oxygen pressure at high altitudes. Several genome-wide scans have elucidated the genetic basis of human high-altitude adaptations.However, the dearth of functional variant information has led to the successful association of only a few candidate genes. In the present study, we employed a candidate gene approach and re-sequenced the EDAR locus in 45 Tibetan individuals to identify mutations involved in hypoxia adaptation. We identified 10 and five quantitative trait-associated mutations for oxygen saturation (SaO_2) and blood platelet count, respectively, at the EDAR locus. Among these, rs10865026 and rs3749110 (associated with SaO_2 and platelet count, respectively) were identified as functional candidate targets. These data demonstrate that EDAR has undergone natural selection in recent human history and indicate an important role of EDAR variants in Tibetan high-altitude adaptations.  相似文献   
90.
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