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Two series of chalcone/aryl carboximidamide hybrids 4a–f and 6a–f were synthesised and evaluated for their inhibitory activity against iNOS and PGE2. The most potent derivatives were further checked for their in vivo anti-inflammatory activity utilising carrageenan-induced rat paw oedema model. Compounds 4c, 4d, 6c and 6d were proved to be the most effective inhibitors of PGE2, LPS-induced NO production, iNOS activity. Moreover, 4c, 4d, 6c and 6d showed significant oedema inhibition ranging from 62.21% to 78.51%, compared to indomethacin (56.27 ± 2.14%) and celecoxib (12.32%). Additionally, 4c, 6a and 6e displayed good COX2 inhibitory activity while 4c, 6a and 6c exhibited the highest 5LOX inhibitory activity. Compounds 4c, 4d, 6c and 6d fit nicely into the pocket of iNOS protein (PDB ID: 1r35) via the important amino acid residues. Prediction of physicochemical parameters exhibited that 4c, 4d, 6c and 6d had acceptable physicochemical parameters and drug-likeness. The results indicated that chalcone/aryl carboximidamides 4c, 4d, 6c and 6d, in particular 4d and 6d, could be used as promising lead candidates as potent anti-inflammatory agents.  相似文献   
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Objectives:The study aimed to determine the effect of adding a school-based plyometric training program (PMT) to physical education (PE) sessions on the strength, balance, and flexibility in primary school girls.Methods:Students from grades 3-6 were randomized equally to a plyometric or control group. In the control group, students took their regular PE classes twice a week. In the plyometric group, students performed PMT twice a week during the initial 20 minutes of every PE session. The Lido Linea closed kinetic chain isokinetic dynamometer, Star excursion balance test (SEBT), and sit-and-reach test were used to assess muscle strength, balance, and flexibility, respectively, before and after nine weeks of training.Results:The improvement in extension peak force (p=0.04) and extension total work (p<0.001) was more prevalent in the PMT group than in the control group. SEBT scores had improved significantly (p<0.05) for all directions in the PMT group, except in the anterior direction, which was highly significant (p<0.001). Hamstring and lower back flexibility had improved more in the PMT group than in the control group (p<0.001).Conclusion:Adding PMT to regular PE classes has a positive and notable effect on muscle strength, balance, and flexibility in primary school students.  相似文献   
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Small heat-shock protein chaperones are important players in the protein quality control system of the cell, because they can immediately respond to partially unfolded proteins, thereby protecting the cell from harmful aggregates. The small heat-shock proteins can form large polydisperse oligomers that are exceptionally dynamic, which is implicated in their function of protecting substrate proteins from aggregation. Yet the mechanism of substrate recognition remains poorly understood, and little is known about what parts of the small heat-shock proteins interact with substrates and what parts of a partially unfolded substrate protein interact with the small heat-shock proteins. The transient nature of the interactions that prevent substrate aggregation rationalize probing this interaction by crosslinking mass spectrometry. Here, we used a workflow with lysine-specific crosslinking and offline nano-liquid chromatography matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry to explore the interaction between the plant small heat-shock protein Hsp21 and a thermosensitive model substrate protein, malate dehydrogenase. The identified crosslinks point at an interaction between the disordered N-terminal region of Hsp21 and the C-terminal presumably unfolding part of the substrate protein.  相似文献   
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The bacteria Bacillus thuringiensis mutant is highly producing melanin pigment with increased ultra violet resistance and insecticidal activity against the potato tuber moth Phthorimaea operculella (Zeller). The results showed that the high decrease of crystal protein formation rate ranged from 100% (B.t.EMS-M2 and B.t.EMS-M6) to 91.82% (B.t.EMS-M9). The EMS–UV-induced mutants (B.t.EMS–UV-2h-1, B.t. EMS–UV-2h-2, B.t.EMS–UV-2h-3, B.t.EMS–UV-2h-5, B.t.EMS–UV-4h-1, B.t.EMS–UV-4h-3 and B.t.EMS–UV-6h-2) showed 100% decrease in the crystal protein formation. Results also showed that the growth rate of B. thuringiensis isolates was detected by measuring the light absorption of culture broth (BP media at pH 8) at the wavelength of 600 nm. The absorbance values of the standard melanin were 2.055 and 0.134 at wavelengths of 226.5 and 602 nm, respectively. This means that the maximum absorbance at wavelength was 226.5 nm, this result is similar to that of the synthetic melanin which has the absorbance of 226 nm. Our experiments detected that the pigment extracted from the mutant isolate B.t.EMS-M3 (EMS-induced mutant) gave the maximum value of absorbance (2.615) at wavelength of 227.5 nm that was similar to standard melanin which gave absorbance value about 2.055 at a wavelength of 226.5 nm. This may be due to the genetic alterations that happened to the mutant isolates due to the mutation by EMS or/and UV irradiation.  相似文献   
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The aim of this study was to investigate the association between C-reactive protein (CRP) gene polymorphism and metabolic syndrome (MetS) with premature coronary artery disease (PCAD). 116 patients with PCAD (58 with MetS and 58 without MetS) and 119 controls were included in the study. CRP gene + 1059 G>C polymorphism was analyzed by polymerase chain reaction. Serum hs-CRP was measured using high-sensitivity enzyme-linked immunosorbent assay. Carriers of C allele of the CRP + 1059 G>C polymorphism had 3.37 fold increased risk to develop MetS in patients with PCAD. In addition CRP gene and hs-CRP levels were independent risk factors for PCAD and MetS. The present study provides new evidence that the presence of CRP + 1059 G>C polymorphism and hs-CRP levels are independent determinants of PCAD and MetS in Egyptians. The results of our study suggest a synergistic effect of CRP C allele with classical risk factors such as hypertension, obesity, dyslipidemia and MetS.  相似文献   
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This study investigates the amphisbaenian species skull which includes cranium, lower jaw and hyoid apparatus. The medial dorsal bones comprise the premaxilla, nasal, frontal and parietal. The premaxilla carries a large medial tooth and two lateral ones. The nasals are paired bones and separated by longitudinal suture. Bones of circumorbital series are frontal, orbitosphenoid and maxilla. The occipital ring consists of basioccipital, supraoccipital and exooccipital. Supraoccipital and basioccipital are single bones while the exo-occipitals are paired. The bones of the palate comprise premaxilla, maxilla, septomaxilla, palatine, pterygoid, ectopterygoid, basisphenoid, parasphenoid, orbitosphenoid and laterosphenoid. Prevomer and pterygoid teeth are absent. Palatine represent by two separate bones. The temporal bones are clearly visible. The lower jaw consists of the dentary, articular, coronoid, supra-angular, angular and splenial. The hyoid apparatus is represented by a Y-shaped structure. The mandible is long and is suspended from the braincase via relatively short quadrate. There is an extensive contact between the long angular and the large triangular coronoid. Thus inter-mandibular joint is bridged completely by the angular and consequently, the lower jaws are relatively rigid and kinetic. The maxillae are suspended from the braincase largely by ligaments and muscles rather than through bony articulation. In conclusion, the skull shape affects feeding strategy in Diplometopon zarudnyi. The prey is ingested and transported via a rapid maxillary raking mechanism.  相似文献   
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Eukaryotic aminoacyl-tRNA synthetases have dispensable extensions appended at the amino- or carboxyl-terminus as compared to their bacterial counterparts. While a synthetic peptide corresponding to the basic amino-terminal extension in yeast Asp-tRNA synthetase binds to DNA, the extension in the intact protein evidently binds to tRNA and enhances the tRNA specificity of Asp-tRNA synthetase. On the other hand, the amino-terminal extension in human Asp-tRNA synthetase, both within the intact protein and as a synthetic peptide, binds to tRNA. Here, the tRNA binding of a synthetic peptide, hKRS(Arg(25)-Glu(42)), corresponding to the amino-terminal extension of human Lys-tRNA synthetase (hKRS) was analyzed. This basic peptide bound to tRNA(Phe) and the apparent-binding constant increased with increasing concentrations of Mg(2+). The hKRS peptide also bound to DNA and polyphosphate; however, the apparent DNA-binding constants decreased at increasing concentrations of Mg(2+). The ability of the hKRS peptide to adopt alpha-helical conformation was demonstrated by NMR and circular dichroism. A Lys-rich peptide derived from the elongation factor 1alpha was also examined and bound to DNA but not to tRNA.  相似文献   
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