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81.
Ulukaya E Acilan C Yilmaz M Yilmaztepe-Oral A Ari F Zik B Ursavas A Tokullugil AH 《Cell biochemistry and function》2010,28(7):565-570
The Fas/Fas Ligand (FasL) system and survivin have counteracting roles in cell survival. Therefore, we explored the role of circulating soluble Fas (sFas) and the tissue levels of Fas and survivin with regard to response to chemotherapy in lung cancer patients. Serum samples from 52 lung cancer patients and 54 control subjects (19 benign lung disease and 35 healthy control subjects) were collected prior to and 24 and 48 h after chemotherapy. sFas was statistically significantly higher in the cancer group than that in the control groups (p < 0.001). Baseline (before chemotherapy) sFas values showed a statistically significant inverse correlation with overall survival (r = ?0.599, p < 0.001). There was a significant increase in serum sFas levels 24 h after treatment (p < 0.05). Contrarily, tissue levels of Fas and survivin were not changed following the chemotherapy (p > 0,05). In conclusion, increased sFas may be an indicator of poor outcome in lung cancer patients. However, cisplatin‐based chemotherapy may not be effective via neither the Fas/FasL system nor survivin pathway. Indeed, larger sample size is required for further evaluation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
82.
Elif Şahin Horasan Gülden Ersöz Musa Göksu Feza Otag Ahmet Oner Kurt Sevim Karaçorlu Ali Kaya 《Mycopathologia》2010,170(4):263-268
Objectives
We aimed to asses possible clinically significant differences between C. parapsilosis and other candida species candidemia receiving care in the intensive care unit (ICU) setting.Methods
The study included 118 adult patients diagnosed as candidemia after admission to the ICU of a university hospital between January 2004 and December 2009. Data about demographic characteristics, underlying diseases, and risk factors for ICU-related candidemia were collected.Results
During the study period, 118 patients with candidemia were identified among 2,853 patients admitted into the ICU. Candidemia was seen in 41.4 cases per 1,000 ICU admissions. The overall incidence of candidemia in ICU patients during the study period was 2.09 per 1,000 hospital admissions. Of the isolates, 18.6% were C. albicans and 81.4% were C. non-albicans. The species most frequently isolated was C. parapsilosis (66.1%, 78/118). The distribution of other Candida spp. was as follows: 15 had C. tropicalis (12.7%) and 3 had C. glabrata (2.5%). By Statistical analysis, when patients with candidemia who had C. parapsilosis were compared with other Candida spp., the following factors were found to be significantly associated with C. parapsilosis fungemia; intravascular catheters (p = 0.008), malignity (p = 0.049) and age (p = 0.039). Relationship was found between C. tropicalis and hematologic malignancies (p = 0.001).Conclusions
When infections with a high mortality such as candidemia is suspected in critically ill patients, it is important to know local risk factors and epidemiological distributions of causative agents in selection of empirical and effective antifungal treatment. 相似文献83.
In this study, a new Pirkle‐type chiral column stationary phase for resolution of β‐methylphenylethyl amine was described by using activated Sepharose 4B as a matrix, L ‐tyrosine as a spacer arm, and an aromatic amine derivative of L ‐glutamic acid as a ligand. The binding capacities of the stationary phase were determined at different pH values (pH = 6, 7, and 8) using buffer solutions as mobile phase, and enantiomeric excess (ee) was determined by HPLC equipped with chiral column. The ee was found to be 47%. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
84.
Nihal Buzkan Serpil Karadaǧ Abdulmurat Kaya Saadettin Baloǧlu Angelantonio Minafra Yair Ben‐Dov 《Journal of Phytopathology》2010,158(6):448-449
Surveys were made in the main grape growing region (Southeast Anatolia) of Turkey for the occurrence of Grapevine leafroll‐associated virus‐5 (GLRaV‐5). Plant samples with typical leafroll symptoms and mealybugs, Planococcus ficus (Signoret) were used for assessing the occurrence of GLRaV‐5 by RT‐PCR. A 272 bp band representing GLRaV‐5 infection was successfully detected in plants and mealybugs in some vineyards of the Southeast Anatolia region and the virus is the first time reported in Turkish vineyards. 相似文献
85.
Ping Lang Tristan Lefebure Wei Wang Paulina Pavinski Bitar Richard J. Meinersmann Katherine Kaya Michael J. Stanhope 《Applied and environmental microbiology》2010,76(6):1913-1925
The purpose of this work was to evaluate the evolutionary history of Campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with certain host species. Genotyping and ClonalFrame analyses of an expanded 16-gene multilocus sequence typing (MLST) data set involving 85 isolates from 4 different hosts species tentatively supported the development of C. coli host-preferred groups and suggested that recombination has played various roles in their diversification; however, geography could not be excluded as a contributing factor underlying the history of some of the groups. Population genetic analyses of the C. coli pubMLST database by use of STRUCTURE suggested that isolates from swine form a relatively homogeneous genetic group, that chicken and human isolates show considerable genetic overlap, that isolates from ducks and wild birds have similarity with environmental water samples and that turkey isolates have a connection with human infection similar to that observed for chickens. Analysis of molecular variance (AMOVA) was performed on these same data and suggested that host species was a significant factor in explaining genetic variation and that macrogeography (North America, Europe, and the United Kingdom) was not. The microarray comparative genomic hybridization data suggested that there were combinations of genes more commonly associated with isolates derived from particular hosts and, combined with the results on evolutionary history, suggest that this is due to a combination of common ancestry in some cases and lateral gene transfer in others.Campylobacter species are a leading bacterial cause of gastroenteritis within the United States and throughout much of the rest of the developed world. According to the CDC, there are an estimated 2 million to 4 million cases of Campylobacter illness each year in the United States (37). Campylobacter jejuni is generally recognized as the predominant cause of campylobacteriosis, responsible for approximately 90% of reported cases, while the majority of the remainder are caused by the closely related sister species Campylobacter coli (27). Not surprisingly, therefore, the majority of research on Campylobacter has centered on C. jejuni, and C. coli is a less studied organism.A multilocus sequence typing (MLST) scheme of C. jejuni was first developed by Dingle et al. (13) on the basis of the genome sequence of C. jejuni NCTC 11168. There have also been a number of studies using the genome sequence data to develop microarrays for gene presence/absence determination across strains of C. jejuni and to identify the core genome components for the species (6, 15, 32, 33, 42, 43, 53, 57). Although C. coli is responsible for fewer food-borne illnesses than C. jejuni, the impact of C. coli is still substantial, and there is also evidence that C. coli may carry higher levels of resistance to some antibiotics (1). C. coli and C. jejuni also tend to differ in their relative prevalences in animal host species and various environmental sources (4, 48, 58), and there is some evidence that both taxa may include groups of host-specific putative ecotype strains (7, 36, 38, 39, 52, 56). At present, there is only a single draft genome sequence available for C. coli, and there are no microarray comparative genomic hybridization data for C. coli strains. Thus, there is no information on intraspecies variability in gene presence/absence in C. coli and how such variability might correlate with host species.The purpose of this work was to develop and apply an expanded 16-locus MLST genotyping scheme to evaluate the evolutionary history of Campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with isolates derived from different host species. 相似文献
86.
U. Celikkol Akcay O. Ercan M. Kavas L. Yildiz C. Yilmaz H. A. Oktem M. Yucel 《Plant Growth Regulation》2010,61(1):21-28
Two cultivars of peanut (Arachis
hypogaea L.) which were designated as resistant (Florispan) and sensitive (Gazipasa) according to their growth retardation under drought
stress conditions were compared for their oxidative damage and antioxidant responses. Sixteen days-old peanut seedlings were
subjected to PEG-6000 solutions of two different osmotic potentials; −0.4 and −0.8 MPa, and various growth parameters, photosystem
II activity, changes in malondialdehyde (MDA), hydrogen peroxide (H2O2) and proline levels, activities of ascorbate peroxidase (APX), catalase (CAT), peroxidase (POX) and gluthatione reductase
(GR) enzymes were determined. Both cultivars exhibited water deficit at −0.8 MPa osmotic potential of PEG-6000 and H2O2 levels significantly increased during exposure to −0.4 MPa osmotic potential. However, H2O2 levels were under control in both cultivars at exposure to −0.8 MPa osmotic potential. Significant proline accumulation was
observed in the tissues of cv. Florispan at −0.8 MPa osmotic potential, whereas proline accumulation did not appear to be
an essential part of the protection mechanism against drought in cv. Gazipasa. No significant variation in chlorophyll fluorescence
values were detected in neither of the cultivars. Enzyme activity measurements revealed that Gazipasa copes well with lesser
magnitudes of drought stress by increasing the activity of mainly APX, and during harsh stress conditions, only APX maintains
its activity in the tissues. In cultivar Florispan, GR activity appears to take role in lesser magnitudes of drought stress,
whereas CAT and APX activities appear to be very crucial antioxidative defenses during intense stress conditions. The results
indicate that, the level of proline and activities of the enzymes CAT and APX are important mechanisms for the maintenance
of drought tolerance in peanut plants. 相似文献
87.
Adnan Ayhanci Sibel Günes Varol Sahinturk Sila Appak Ruhi Uyar Mustafa Cengiz Yilmaz Altuner Suzan Yaman 《Biological trace element research》2010,136(2):171-179
The anticancer drug cyclophosphamide (CP) has nephrotoxic effects besides its urotoxicity, which both in turn limit its clinical
utility. The nephrotoxicity of CP is less common compared to its urotoxicity, and not much importance has been given for the
study of mechanism of CP-induced nephrotoxicity so far. Overproduction of reactive oxygen species (ROS) during inflammation
is one of the reasons of the kidney injury. Selenoproteins play crucial roles in regulating ROS and redox status in nearly
all tissues; therefore, in this study, the nephrotoxicity of CP and the possible protective effects of seleno l-methionine (SLM) on rat kidneys were investigated. Forty-two Sprague–Dawley rats were equally divided into six groups of seven
rats each. The control group received saline, and other rats were injected with CP (100 mg/kg), SLM (0.5 or 1 mg/kg), or CP + SLM
intraperitoneally. Malondialdehyde (MDA) and glutathione (GSH) levels in kidney homogenates of rats were measured, and kidney
tissues were examined under the microscope. CP-treated rats showed a depletion of renal GSH levels (28% of control), while
CP + SLM-injected rats had GSH values close to the control group. MDA levels increased 36% of control following CP administration,
which were significantly decreased after SLM treatment. Furthermore, these biochemical results were supported by microscopical
observations. In conclusion, the present study not only points to the therapeutic potential of SLM in CP-induced kidney toxicity
but also indicates a significant role for ROS and their relation to kidney dysfunction. 相似文献
88.
Akin Yilmaz Sevda Menevse Yildirim Bayazit Recep Karamert Volkan Ergin Adnan Menevse 《Biochemical genetics》2010,48(3-4):248-256
Most nonsyndromic hearing losses are caused by mutations in the GJB2 gene, and studies have revealed that the forms and frequencies of these mutations are largely dependent on ethnic origin. In the present study, we aimed to characterize the mutation profiles of 151 patients with hearing loss in Turkey. The entire coding region of the GJB2 was directly sequenced in all patients. We found 35 (23.2%) individuals carrying GJB2 mutations. Seven different mutations were identified, five of which were previously known (35delG, delE120, R184P, M163V, L90P), the remaining two being novel variants (M34V, L205V). The most common mutation was 35delG followed by delE120. The 35delG mutation was homozygous in 22 cases (14.5%) and heterozygous in 4 cases (2.6%). Compound heterozygosity for 35delG was also observed. The delE120 mutation was found in three patients in homozygous form. A homozygous L90P and heterozygous mutations M163V and M34V were found in single cases. 相似文献
89.
Kadir Ugurtan Yilmaz Makbule Yanar Sezai Ercisli Hatice Sahiner Tuncer Taskin Yasar Zengin 《Biochemical genetics》2010,48(9-10):873-878
The genus Crataegus is well distributed in Turkey as a wild plant, with numerous, inherently variable species and genotypes. RAPD markers were used to study 17 hawthorn genotypes belonging to Crataegus monogyna ssp. monogyna Jacq (2 genotypes), C. monogyna ssp. azarella Jacq (1), Crataegus pontica K.Koch (3), Crataegus orientalis var. orientalis Pallas Ex Bieb (3), Crataegus pseudoheterophylla Pojark (1), Crataegus aronia var. dentata Browicz (1), C. aronia var. aronia Browicz (4), and Crateagus × bornmuelleri Zabel (2). The 10 RAPD primers produced 72 polymorphic bands (88% polymorphism). A dendrogram based on Jaccard’s index included four major groups and one outgroup according to taxa. The lowest genetic variability was observed within C. aronia var. aronia genotypes. The study demonstrated that RAPD analysis is efficient for genotyping wild-grown hawthorns. 相似文献
90.
Li Y Laue K Temtamy S Aglan M Kotan LD Yigit G Canan H Pawlik B Nürnberg G Wakeling EL Quarrell OW Baessmann I Lanktree MB Yilmaz M Hegele RA Amr K May KW Nürnberg P Topaloglu AK Hammerschmidt M Wollnik B 《American journal of human genetics》2010,87(6):757-767
Altered Bone Morphogenetic Protein (BMP) signaling leads to multiple developmental defects, including brachydactyly and deafness. Here we identify chondroitin synthase 1 (CHSY1) as a potential mediator of BMP effects. We show that loss of human CHSY1 function causes autosomal-recessive Temtamy preaxial brachydactyly syndrome (TPBS), mainly characterized by limb malformations, short stature, and hearing loss. After mapping the TPBS locus to chromosome 15q26-qterm, we identified causative mutations in five consanguineous TPBS families. In zebrafish, antisense-mediated chsy1 knockdown causes defects in multiple developmental processes, some of which are likely to also be causative in the etiology of TPBS. In the inner ears of zebrafish larvae, chsy1 is expressed similarly to the BMP inhibitor dan and in a complementary fashion to bmp2b. Furthermore, unrestricted Bmp2b signaling or loss of Dan activity leads to reduced chsy1 expression and, during epithelial morphogenesis, defects similar to those that occur upon Chsy1 inactivation, indicating that Bmp signaling affects inner-ear development by repressing chsy1. In addition, we obtained strikingly similar zebrafish phenotypes after chsy1 overexpression, which might explain why, in humans, brachydactyly can be caused by mutations leading either to loss or to gain of BMP signaling. 相似文献