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201.
Little is known about the effective role of Hypericum perforatum on hepatic ischemia–reperfusion (I/R) injury in rats. Hence, albino rats were subjected to 45 min of hepatic ischemia followed by 60 min of reperfusion period. Hypericum perforatum extract (HPE) at the dose of 50 mg/kg body weight (HPE50) was intraperitonally injected as a single dose, 15 min prior to ischemia. Rats were sacrificed at the end of reperfusion period and then, biochemical investigations were made in serum and liver tissue. Liver tissue homogenates were used for the measurement of malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GPx) levels. At the same time alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were assayed in serum samples and compared statistically. While the ALT, AST, LDH activities and MDA levels were significantly increased, CAT and GPx activities significantly decreased in only I/R-induced control rats compared to normal control rats (p < 0.05). Treatment with HPE50 significantly decreased the ALT, AST, LDH activities and MDA levels, and markedly increased activities of CAT and GPx in tissue homogenates compared to I/R-induced rats without treatment–control group (p < 0.05). In oxidative stress generated by hepatic ischemia–reperfusion, H. perforatum L. as an antioxidant agent contributes an alteration in the delicate balance between the scavenging capacity of antioxidant defence systems and free radicals in favour of the antioxidant defence systems in the body.  相似文献   
202.

Objective

Interleukin-4 (IL-4) is a strong chondroprotective cytokine and polymorphisms within this gene may be a risk factor for osteoarthritis (OA). We aimed to investigate genotype and allele frequencies of IL-4 gene intron 3 variable number of tandem repeats (VNTR) polymorphism in patients with knee OA in a Turkish population.

Methods

The study included 202 patients with knee OA and 180 healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers followed by restriction fragment length polymorphism (RFLP) analysis.

Results

Our result show that there was statistically significant difference between knee OA patients and control group with respect to IL-4 genotype distribution and allele frequencies (p = 0.000, OR: 0.20, 95% CI: 0.10–0.41, OR: 0.22, 95% CI: 0.12–0.42, respectively).

Conclusions

Our findings suggest that there is an association of IL-4 gene intron 3 VNTR polymorphism with susceptibility of a person for development of knee OA. As a result, IL-4 gene intron 3 VNTR polymorphism could be a genetic marker in OA in a Turkish study population. This is the first association study that evaluates the associations between IL-4 gene VNTR polymorphism and knee OA.  相似文献   
203.
The complicated muscle activity of the human tongue and the resultant surface shapes can give us important clues about speech motor control and pathological tongue motion. This study uses tagged magnetic resonance imaging to provide a 2D surface deformation analysis of the tongue, as well as a 4D compression–expansion analysis, during utterances of four different syllables (/ba/, /ta/, /sha/ and /ga/). All speech tasks were performed several times to confirm the repeatability of the motion analysis. The results showed that the tongue has unique motion patterns for utterances of different syllables, and these differences, which may not be observed by a simple surface analysis, can be examined thoroughly by a 4D motion model-based analysis of the tongue muscles.  相似文献   
204.
A case of fatal salmonellosis in a Eurasian eagle-owl (Bubo bubo) from Bursa Province (northwestern Turkey) is described. The organs of the bird were examined histopathologically and microbiologically. Macroscopic and microscopic findings were consistent with a Salmonella infection. Salmonella enterica subspecies enterica serovar Enteritidis (S. Enteritidis) phage type (PT) 21b was isolated from the liver and spleen in pure culture and from the intestine. The isolate was susceptible to amoxycillin/clavulanic acid, ampicillin, chloramphenicol, gentamicin, kanamycin, tetracycline, and trimethoprim/sulphamethoxazole. This is the first report of an isolation of salmonellae from a wild bird species from Turkey and the first time S. Enteritidis PT21b has been reported from Turkey.  相似文献   
205.
206.

Background

Breast cancer is a remarkably heterogeneous disease. Luminal, basal-like, “normal-like”, and ERBB2+ subgroups were identified and were shown to have different prognoses. The mechanisms underlying this heterogeneity are poorly understood. In our study, we explored the role of cellular differentiation and senescence as a potential cause of heterogeneity.

Methodology/Principal Findings

A panel of breast cancer cell lines, isogenic clones, and breast tumors were used. Based on their ability to generate senescent progeny under low-density clonogenic conditions, we classified breast cancer cell lines as senescent cell progenitor (SCP) and immortal cell progenitor (ICP) subtypes. All SCP cell lines expressed estrogen receptor (ER). Loss of ER expression combined with the accumulation of p21Cip1 correlated with senescence in these cell lines. p21Cip1 knockdown, estrogen-mediated ER activation or ectopic ER overexpression protected cells against senescence. In contrast, tamoxifen triggered a robust senescence response. As ER expression has been linked to luminal differentiation, we compared the differentiation status of SCP and ICP cell lines using stem/progenitor, luminal, and myoepithelial markers. The SCP cells produced CD24+ or ER+ luminal-like and ASMA+ myoepithelial-like progeny, in addition to CD44+ stem/progenitor-like cells. In contrast, ICP cell lines acted as differentiation-defective stem/progenitor cells. Some ICP cell lines generated only CD44+/CD24-/ER-/ASMA- progenitor/stem-like cells, and others also produced CD24+/ER- luminal-like, but not ASMA+ myoepithelial-like cells. Furthermore, gene expression profiles clustered SCP cell lines with luminal A and “normal-like” tumors, and ICP cell lines with luminal B and basal-like tumors. The ICP cells displayed higher tumorigenicity in immunodeficient mice.

Conclusions/Significance

Luminal A and “normal-like” breast cancer cell lines were able to generate luminal-like and myoepithelial-like progeny undergoing senescence arrest. In contrast, luminal B/basal-like cell lines acted as stem/progenitor cells with defective differentiation capacities. Our findings suggest that the malignancy of breast tumors is directly correlated with stem/progenitor phenotypes and poor differentiation potential.  相似文献   
207.
Defining "healthy weight" is not easy and for an adolescent with all concerns about newly developing physiognomy it is even harder. The aim of this study was to find out the frequency of obesity and the association between the body mass index (BMI), weight-control behaviors and self-perceived body weight status in high school students of a southern city of Turkey. The students from 10 schools were randomly selected among 46,271 students of 72 high schools in Adana from 1999 to 2000. The response rate was 94.8% (2352/2480). The Turkish version of Youth Risk Behavior Survey Questionnaire (YRBSQ) was completed by the students. The students' weights and heights were measured. The mean age was 16.5 +/- 1.0 years of age (range = 14-21 years). The mean BMI was 21.0 +/- 3.1, 25.5% of students were underweight, 65.7% were normal, 6.4% were overweight and 2.3% were obese (p = 0.0001). Of all students, 24.3% defined themselves as thin, 45.3% as normal, 24.9% as overweight and 5.5% as obese (p = 0.0001). The percentage of girls defining their body weight as overweight and obese was significantly higher than the boys (p = 0.0001). Of all students, 35.5% wanted to lose weight, 22.3% wanted to gain weight, 27.8% wanted to keep their current weight. Intention (p = 0.0001) and interventions to lose weight such as going on a diet (p = 0.0001), provocative vomiting (p = 0.0001) and 24-hours starving (p = 0.0001) were significantly higher in girls than boys. Of students, 26.8% (n=620) were on a diet program either to lose or to keep their body weight. There was significant relationship between being on a diet program and intention to change body weight (p = 0.047). We concluded that adolescents living in Adana have relatively higher risk of being underweight than being obese and have unhealthy weight changing plans due to their misperception of their body images. Adolescents may be unconscious on plans and attempts to change their body weights and nutrition and we suggest that education on nutrition and health is required for adolescents.  相似文献   
208.
Werner syndrome (WS) is an autosomal recessive segmental progeroid syndrome caused by null mutations at the WRN locus, which codes for a member of the RecQ family of DNA helicases. Since 1988, the International Registry of Werner syndrome had enrolled 130 molecularly confirmed WS cases from among 110 worldwide pedigrees. We now report 18 new mutations, including two genomic rearrangements, a deep intronic mutation resulting in a novel exon, a splice consensus mutation leading to utilization of the nearby splice site, and two rare missense mutations. We also review evidence for founder mutations among various ethnic/geographic groups. Founder WRN mutations had been previously reported in Japan and Northern Sardinia. Our Registry now suggests characteristic mutations originated in Morocco, Turkey, The Netherlands and elsewhere.  相似文献   
209.
Yazici  M. Atilla  Asif  Muhammad  Tutus  Yusuf  Ortas  Ibrahim  Ozturk  Levent  Lambers  Hans  Cakmak  Ismail 《Plant and Soil》2021,459(1-2):19-21
Plant and Soil - Grass pea is a legume species with recognized resistance to several diseases and thus important for the improvement of related major legume crops. It is infected by the soil-borne...  相似文献   
210.
Saruhan Guler  N.  Ozturk  K.  Sezgin  A.  Altuntas  C.  Kadioglu  A.  Terzi  R. 《Russian Journal of Plant Physiology》2021,68(6):1152-1160
Russian Journal of Plant Physiology - Alpha lipoic acid (ALA) is a potent antioxidant molecule that has positive effects on plant growth and the adaptation of plants to environmental stresses....  相似文献   
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