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121.
In this study, it was hypothesized that Pluronic F-68 (PLF-68) increases matrix synthesis of osteoarthritis (OA) chondrocytes in addition to its well-documented cell survival effect. To test this hypothesis, rat articular chondrocytes were embedded in agarose discs and were exposed to 5-azacytidine (Aza-C) to induce OA-like alterations. Chondrocytes were then treated with PLF-68 (8 and 12 mg/ml) for 10 days. Aza-C-exposed and PLF-68-untreated chondrocytes and Aza-C-unexposed and PLF-68-untreated chondrocytes were used as negative and positive control groups, respectively. Dynamic hydrostatic pressure (max 0.2 MPa, 0.1 Hz) was applied to discs for 30 min/day (5 days/week). Cell viability, collagen and proteoglycan deposition in discs were determined. Unconfined compression stress relaxation tests were performed to determine peak stress and material parameters of discs—namely spring constants (k 1 and k 2), damping coefficient (η), instantaneous modulus (E 0) and relaxed modulus (E ) using Kelvin model to evaluate the functional coherence of the matrix. PLF-68 treatment significantly increased the collagen deposition in discs and viability of OA-like chondrocytes. A dose-dependent increase was also observed for elastic stiffness parameters (k 1, k 2, E 0 and E ). Same positive effect of PLF-68 was not observed for proteoglycan deposition. However, dose-dependent increase in η suggests that PLF-68 treatment resulted with the deposition of functional matrix. This is the first study which reports that PLF-68 has also positive effect on collagen synthesis of OA cells. As a conclusion, our results suggest that PLF-68 has a potential for recovery from OA-like alterations, which should be further analyzed.  相似文献   
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Recently, sodium tungstate was suggested to improve cardiac performance of diabetic rats in perfused hearts based on its insulinomimetic activity. In this study, we aimed to investigate the cellular and molecular mechanisms underlying this beneficial effect of sodium tungstate. Tungstate was administered (100 mg/kg/day) to diabetic and control rats intragastrically for 6 weeks. Blood glucose levels increased, whereas body weight, heart weight and plasma insulin levels decreased significantly in diabetic animals. Interestingly, none of these parameters was changed by tungstate treatment. On the other hand, fractional shortening and accompanying intracellular Ca(2+) [Ca(2+)](i) transients of isolated ventricular myocytes were measured, and sodium tungstate was found to improve the peak shortening and the amplitude of [Ca(2+)](i) transients in diabetic cardiomyocytes. Potassium and L-type Ca(2+) currents were also recorded in isolated ventricular cells. Significant restoration of suppressed I (to) and I (ss) was achieved by tungstate administration. Nevertheless, L-type calcium currents did not change either in untreated or treated diabetic rats. Tissue biochemical parameters including TBARS, protein carbonyl content, xanthine oxidase (XO) and xanthine dehydogenase (XDH) were also determined, and diabetes revealed a marked increase in TBARS and carbonyl content which were decreased significantly by tungstate treatment. Conversely, although XO and XDH activities didn't change in untreated diabetic rats, a remarkable but insignificant decrease was detected in treated animals. In conclusion, tungstate treatment improved diabetes-induced contractile abnormalities via restoration of dysregulated [Ca(2+)](i) and altered ionic currents. This beneficial effect is due to antioxidant property of sodium tungstate rather than normalization of hyperglycemia.  相似文献   
124.
Plants accumulate high levels of Gamma amino butyric acid (GABA) in response to different environmental stresses and GABA metabolism has different functions such as osmotic and pH regulation, bypass of tricarboxylic acid cycle, and C:N balance. The cytoplasmic male sterile (CMS) II mutant of Nicotiana sylvestris has a deletion in the mitochondrial gene nad7 which encodes the NAD7 subunit of complex I which causes increased leaf respiration, impaired photosynthesis, slower growth and increased amino acid levels. In this study we aimed to elucidate the role of GABA and GABA metabolism in different genotypes of the same plant system under salt stress (100mM NaCl) in short (24h) and long (7, 14 and 21 days) terms. We have investigated the differences in leaf fresh and dry weights, relative water content, photosynthetic efficiency (F(v)/F(m)), glutamate dehydrogenase (GDH, EC 1.4.1.4) and glutamate decarboxylase (GAD, EC 4.1.1.15) enzyme activities, GABA content and GAD gene expression profiles. GDH activity showed variations in CMSII and wild type (WT) plants in the first 24h. GAD gene expression profiles were in good agreement with the GAD enzyme activity levels in CMSII and WT plants after 24h. In long-term salinity, GAD activities increased in WT but, decreased in CMSII. GABA accumulation in WT and CMSII plants in short and long term was induced by salt stress. Variations in GDH and GAD activities in relation to GABA levels were discussed and GABA metabolism has been proposed to be involved in better performance of CMSII plants under long term salinity.  相似文献   
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This study was conducted for typing Salmonella enterica subspecies enterica strains in Turkey using pulsed–field gel electrophoresis (PFGE) and plasmid DNA profile analysis. Fourty-two strains were isolated from clinical samples obtained from unrelated patients with acute diarrhea. The samples were collected from state hospitals and public health laboratories located at seven provinces in different regions of Turkey at different times between 2004 and 2010. The strains were determined to belong to 4 different serovars. The Salmonella enterica strains belonged to the serovars Salmonella Enteritidis (n = 23), Salmonella Infantis (n = 14), Salmonella Munchen (n = 2), and Salmonella Typhi (n = 3). Forty-two Salmonella enterica strains were typed with PFGE methods using XbaI restriction enzyme and plasmid analysis. At the end of typing, 11 different PFGE band profiles were obtained. Four different PFGE profiles (type 1, 4, 9, and 10) were found among serotype S. Enteritidis species, 3 different PFGE profiles (type 3, 5, 6) were found among S. Infantis species, 2 different PFGE profiles were found among S. Typhi species (type 2 and 11), and 2 different PFGE profiles were found among S. Munchen species (type 7, 8). The UPGMA dendrogram was built on the PFGE profiles. In this study, it was determined that 4 strains of 42 Salmonella enterica strains possess no plasmid, while the isolates have 1–3 plasmids ranging from 5.0 to 150 kb and making 12 different plasmid profiles (P1–P12). In this study, we have applied the analysis of the PFGE patterns and used bioinformatics methods to identify both inter and intra serotype relationships of 4 frequently encountered serotypes for the first time in Turkey.  相似文献   
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University laboratories involve various occupational hazards during the research and course activities, which might affect health and safety of both researchers and students, including chemical, physical, electrical, mechanical, as well as ergonomic and psychosocial risk factors. There are many aspects open to improvements in Occupational Health and Safety management of laboratories, and it is required to deal with risks, reduce them in an acceptable level, and implement control measures. In this study, a risk assessment approach is proposed for the university laboratory operations. The proposed approach incorporates 5S methodology, failure modes and effects analysis (FMEA), interval type-two fuzzy sets (IT2FSs), analytic hierarchy process (AHP), and the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). AHP is injected into IT2FSs in the phase of evaluation and weighting of severity (S), occurrence (O), and detectability (D) parameters of FMEA. By applying IT2FVIKOR, it is aimed at prioritizing the emerged hazards in the chemical laboratory of the observed university. The proposed approach reveals the important hazards and suggests control measures for managing them. The study methodologically contributes to risk assessment in the knowledge, while a case study in a chemical laboratory of a newly established university offers an insight into education industry in safety improvement.  相似文献   
128.
Recent studies support the involvement of supraspinal networks in control of bipedal human walking. Part of this evidence encompasses studies, including our previous work, demonstrating that gait kinematics and limb coordination during treadmill walking can be inferred from the scalp electroencephalogram (EEG) with reasonably high decoding accuracies. These results provide impetus for development of non-invasive brain-machine-interface (BMI) systems for use in restoration and/or augmentation of gait- a primary goal of rehabilitation research. To date, studies examining EEG decoding of activity during gait have been limited to treadmill walking in a controlled environment. However, to be practically viable a BMI system must be applicable for use in everyday locomotor tasks such as over ground walking and turning. Here, we present a novel protocol for non-invasive collection of brain activity (EEG), muscle activity (electromyography (EMG)), and whole-body kinematic data (head, torso, and limb trajectories) during both treadmill and over ground walking tasks. By collecting these data in the uncontrolled environment insight can be gained regarding the feasibility of decoding unconstrained gait and surface EMG from scalp EEG.  相似文献   
129.
OBJECTIVE: To analyze fine-needle aspiration cytology (FNAC) material from 37 cases of breast glycogen-rich clear cell cancer (GRCC) and correlate cytomorphologic features with histologic appearance to determine characteristics of GRCC on FNAC. STUDY DESIGN: We reviewed cytologic features of 37 cases of breast GRCC from the archives of Ege University Hospital diagnosed between 1994 and 2006. RESULTS: Thirty-seven patients with available aspirate and confirmed GRCC were identified. The female patients ranged from 32 to 81 years (mean 52 years). The initial cytologic diagnoses were adenocarcinoma for 27 and atypical or suspicious for cancer for 10. The cytologic picture was characterized by hypercellular tumor cells in loosely cohesive syncytial groups and some single cells. Most tumor cells had abundant, finely granular eosinophilic cytoplasm or foamy to clear cytoplasm with well-defined cytoplasmic membranes and moderate to marked nuclear pleomorphism with prominent nucleoli. Histologic examination confirmed all cases to be pure GRCC. ConCLUSION: Breast GRCC is a rare, distinct category with cytologic features that overlap considerably with those of other carcinomas. Awareness of variability in cytomorphologic appearance of GRCC and routine assessment for glycogen facilitate accurate diagnosis of these lesions by FNAC and enable prompt treatment of these poor-prognosis breast cancers.  相似文献   
130.
Matrix metalloproteinase-9 (MMP-9) and NADPH oxidase contribute to blood-brain barrier (BBB) disruption after ischemic stroke. We have previously shown that normobaric hyperoxia (NBO) treatment reduces MMP-9 and oxygen free radical generation in ischemic brain. In this study, we tested the hypothesis that NBO protects the BBB through inhibiting NADPH oxidase-mediated MMP-9 induction in transient focal cerebral ischemia. Male Sprague-Dawley rats (n = 69) were given NBO (95% O2) or normoxia (21% O2) during 90-min filament occlusion of the middle cerebral artery. Cerebral microvessels were isolated for analyzing MMP-9 and NADPH oxidase. BBB damage was non-invasively quantified with magnetic resonance imaging. In normoxic rats, both NADPH oxidase catalytic subunit gp91(phox) and MMP-9 expression were up-regulated in ischemic hemispheric microvessels after 90-min middle cerebral artery occlusion with 22.5 h reperfusion. Inhibition of NADPH oxidase with apocynin reduced the MMP-9 increase, indicating a causal link between NADPH oxidase-derived superoxide and MMP-9 induction. NBO treatment inhibited gp91(phox) expression, NADPH oxidase activity, and MMP-9 induction, which led to significantly less BBB damage and brain edema in the ischemic brain. These results suggest that gp91(phox) containing NADPH oxidase plays an important role in MMP-9 induction in ischemic BBB microvasculature, and that NBO treatment may attenuate MMP-9 induction and brain edema through inhibiting NADPH oxidase after transient cerebral ischemia.  相似文献   
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