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421.
Dayan K Keser A Konyalioglu S Erturk M Aydin F Sengul G Dagci T 《Life sciences》2012,90(9-10):360-364
AimsAlthough hyperbaric oxygen (HBO) treatment following spinal cord injury (SCI) have been studied in terms of neurological function and tissue histology, there is a limited number studies on spinal cord tissue enzyme levels.Main methodsThe effect of HBO treatment in SCI was investigated by measuring superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), nitric oxide synthase (NOS) and nitric oxide (NO) activity in the injured tissue. SCI was induced by applying an aneurysm clip extradurally at the level of T9-T11 vertebrae. Preoperative HBO (preopHBO) treatment was applied for 5 days and postoperative HBO (postopHBO) for 7 days.Key findingsIn the preopHBO group, a significant decrease was observed in NOS and NO compared to the SCI group. There was a decrease in SOD, NOS and NO in the postopHBO group when compared to the SCI group. In the pre–postHBO group SOD, GPx, NOS and NO decreased significantly. There was a decrease in SOD in postopHBO compared to preopHBO. In the prepostopHBO, SOD decreased significantly compared to that in the preopHBO group. The prepostopHBO presented a significant decrease in GPx compared to postopHBO (p < 0.05 for all parameters). No significant difference was observed for catalase for all groups. Significant improvement was found in BBB scores for both postopHBO and prepostHBO groups when compared to the SCI group (p < 0.05).SignificanceHBO treatment was found to be beneficial following SCI in terms of biochemical parameters and functional recovery in the postoperative period. 相似文献
422.
Hakan N Aydin M Erdogan O Cavusoglu YH Aycan Z Ozaltin F Zenciroglu A Apaydin S Gunes R Sahin G Cinar G Okumus N 《Genetic counseling (Geneva, Switzerland)》2012,23(2):255-261
Denys-Drash syndrome (DDS) is a rare disorder characterized by glomerulopathy, genital abnormalities and predisposition to Wilms' tumor. It is associated with constitutional Wilms'tumor suppressor 1 (WT1) gene mutations, in which the majority being missense mutations in the zinc-finger region. Here, we present a newborn with DDS, associated with a novel heterozygous missense mutation, p.Asp396His, on exon 9 of WT1. 相似文献
423.
Aydin A Ibrikçi T Akçali ID 《Computer methods in biomechanics and biomedical engineering》2012,15(7):753-759
In the field of orthopaedics, treatment of extremity deformities can be realised by means of external fixators. However, control of such biomedical system is very difficult. Some different mathematical models have been developed to improve quality of this service. Most of the parameters, which are used in these models, have been obtained from two orthogonal X-ray images: one from anteroposterior, AP, direction and the other from a lateral, L, direction. The quality of the results of this model is dependent on the accuracy of the input parameters. Measuring these parameters is a time-consuming issue, and the accuracy of the results is also low. To increase the quality of the measurement, the reference points should be chosen from the edges of the biomedical system, and it is important to find the edges without noise. To achieve this purpose, Sobel edge detector, binary large object analysis, thresholding and inverting are applied as image processing steps. The results are compared with manual measurement values which have been obtained earlier. The results show that semi-automatic measurement of the parameters is more accurate and faster than manual measurement. It shows that the efficiency of the fixator method has been improved. 相似文献
424.
The purpose of our study was to determine the percentages of α-naphthyl acetate esterase (ANAE)- and acid phosphatase (ACP)-positive peripheral blood lymphocytes (PBL), the presence of the ANAE and ACP enzymes in leukocytes, and the proportion of PBL in greyhounds. Peripheral blood samples were collected from the cephalic antebrachial vein of 14 (7 animals of each sex) healthy 1-2-year-old greyhounds. Mean percentages of ANAE-positive PBL were found to be 73.29 ± 0.95% in female and 74.29 ± 2.21% in male dogs. The difference between mean values of the genders was not statistically significant. The ACP values were 36.00 ± 2.94% for females and 33.57 ± 2.15% for males. No significant differences were found with regard to gender. For both enzymes, although monocytes and eosinophilic granulocytes displayed a positive reaction, neutrophils gave negative reactions. The proportion of PBL was 36.29 ± 5.31% and 33.00 ± 2.38 % in female and male dogs, respectively. The differences were not significant. 相似文献
425.
Keith P. Romano Akbar Ali Cihan Aydin Djade Soumana Ay?egül ?zen Laura M. Deveau Casey Silver Hong Cao Alicia Newton Christos J. Petropoulos Wei Huang Celia A. Schiffer 《PLoS pathogens》2012,8(7)
Hepatitis C virus (HCV) infects over 170 million people worldwide and is the leading cause of chronic liver diseases, including cirrhosis, liver failure, and liver cancer. Available antiviral therapies cause severe side effects and are effective only for a subset of patients, though treatment outcomes have recently been improved by the combination therapy now including boceprevir and telaprevir, which inhibit the viral NS3/4A protease. Despite extensive efforts to develop more potent next-generation protease inhibitors, however, the long-term efficacy of this drug class is challenged by the rapid emergence of resistance. Single-site mutations at protease residues R155, A156 and D168 confer resistance to nearly all inhibitors in clinical development. Thus, developing the next-generation of drugs that retain activity against a broader spectrum of resistant viral variants requires a comprehensive understanding of the molecular basis of drug resistance. In this study, 16 high-resolution crystal structures of four representative protease inhibitors – telaprevir, danoprevir, vaniprevir and MK-5172 – in complex with the wild-type protease and three major drug-resistant variants R155K, A156T and D168A, reveal unique molecular underpinnings of resistance to each drug. The drugs exhibit differential susceptibilities to these protease variants in both enzymatic and antiviral assays. Telaprevir, danoprevir and vaniprevir interact directly with sites that confer resistance upon mutation, while MK-5172 interacts in a unique conformation with the catalytic triad. This novel mode of MK-5172 binding explains its retained potency against two multi-drug-resistant variants, R155K and D168A. These findings define the molecular basis of HCV N3/4A protease inhibitor resistance and provide potential strategies for designing robust therapies against this rapidly evolving virus. 相似文献
426.
Background
Pandemic and seasonal respiratory viruses are a major global health concern. Given the genetic diversity of respiratory viruses and the emergence of drug resistant strains, the targeted disruption of human host-virus interactions is a potential therapeutic strategy for treating multi-viral infections. The availability of large-scale genomic datasets focused on host-pathogen interactions can be used to discover novel drug targets as well as potential opportunities for drug repositioning.Methods/Results
In this study, we performed a large-scale analysis of microarray datasets involving host response to infections by influenza A virus, respiratory syncytial virus, rhinovirus, SARS-coronavirus, metapneumonia virus, coxsackievirus and cytomegalovirus. Common genes and pathways were found through a rigorous, iterative analysis pipeline where relevant host mRNA expression datasets were identified, analyzed for quality and gene differential expression, then mapped to pathways for enrichment analysis. Possible repurposed drugs targets were found through database and literature searches. A total of 67 common biological pathways were identified among the seven different respiratory viruses analyzed, representing fifteen laboratories, nine different cell types, and seven different array platforms. A large overlap in the general immune response was observed among the top twenty of these 67 pathways, adding validation to our analysis strategy. Of the top five pathways, we found 53 differentially expressed genes affected by at least five of the seven viruses. We suggest five new therapeutic indications for existing small molecules or biological agents targeting proteins encoded by the genes F3, IL1B, TNF, CASP1 and MMP9. Pathway enrichment analysis also identified a potential novel host response, the Parkin-Ubiquitin Proteasomal System (Parkin-UPS) pathway, which is known to be involved in the progression of neurodegenerative Parkinson''s disease.Conclusions
Our study suggests that multiple and diverse respiratory viruses invoke several common host response pathways. Further analysis of these pathways suggests potential opportunities for therapeutic intervention. 相似文献427.
428.
The aim of the present study was to determine the identity, seasonal activity and distribution of tick species of cattle in
the West Aegean region of Turkey between June 2006 and May 2008. Nine villages within three provinces, viz. Manisa, Izmir and Aydin, were included in the study and a total of 75 animal barns were visited monthly for a period of 24 months
and 443 cattle were examined for the presence of ticks. It was determined that 23% of cattle were infested with ticks. A total
of 19,679 adult ticks were collected. The most abundant tick species was Hyalomma marginatum (33.5%) and H. excavatum (16.9%) in the study area. Seasonal appearance of the adult ticks varied among species. Adult ticks of the Hyalomma genus were present throughout the year, although in smaller numbers during the winter. Species of Rhipicephalus were detected in all seasons except autumn. Rhipicephalus (Boophilus) annulatus was identified in July and August, Haemaphysalis parva was detected during the autumn. Ixodes ricinus and Dermacentor marginatus were identified during spring, autumn and winter. The study demonstrated the presence of I. ricinus, D. marginatus, Hyalomma rufipes and Hae. parva for the first time in the West Aegean region of Turkey. 相似文献
429.
Danielle C. Lohman Deniz Aydin Helaina C. Von Bank Robert W. Smith Vanessa Linke Erin Weisenhorn Molly T. McDevitt Paul Hutchins Emily M. Wilkerson Benjamin Wancewicz Jason Russell Matthew S. Stefely Emily T. Beebe Adam Jochem Joshua J. Coon Craig A. Bingman Matteo Dal Peraro David J. Pagliarini 《Molecular cell》2019,73(4):763-774.e10
430.
Merve Aydin Semra Kustimur Ayse Kalkanci Tugce Duran 《Revista iberoamericana de micología》2019,36(3):129-138
BackgroundThe prevalence of opportunistic yeast infections has increased in recent decades as the result of an increasing immunocompromised patient population.AimsTo evaluate ribosomal RNA (rRNA) gene sequence to identify medically important yeast species, to investigate the performance of both the rRNA gene internal transcribed spacer (ITS) and D1/D2 region in identifying clinically relevant yeasts, and to compare these results with those of a standard phenotypic method.MethodsBoth regions from 50 yeast strains, comprising 45 clinical isolates and 5 reference strains, were amplified using PCR and then sequenced. The sequences were compared to reference data available from the GenBank database of the National Center for Biotechnology Information using the BLASTn tool.ResultsUsing ID32C, 88% (44/50) of all strains were identified accurately at the species level, although 6% were misidentified; two Candida eremophila isolates were identified as Candida glabrata and Candida tropicalis, and one Saprochaete clavata isolate was identified as Saprochaete capitata. Two of the four isolates identified by phenotypic methods as Trichosporon asahii were defined so by analyzing the ITS region, but the remaining two were not distinguishable from closely related species. Based on the D1/D2 region, these four isolates had 100% sequence identity with T. asahii, Trichosporon japonicum, and Trichosporon asteroides. The isolate identified as Trichosporon inkin using ID32C could not be distinguished from Trichosporon ovoides by analyzing the ITS and D1/D2 regions.ConclusionsIdentifying medically important yeasts by sequencing the ITS and D1/D2 region is a rapid and reliable alternative to conventional identification methods. For a diagnostic algorithm, we suggest a two-step procedure integrating conventional methods (e.g. microscopic morphology on corn meal agar with Tween® 80 and API ID32C®) and sequence analysis of the ITS and D1/D2 region. 相似文献