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81.
Although HER2/PTEN pathway is commonly disrupted in cancer, association of HER2 and PTEN polymorphisms with breast cancer (BC) remains controversial. We investigated the HER2 Ile655 Val and PTEN IVS4 polymorphisms in patients with BC in Turkish population. HER2 Ile655Val (rs 1136201) and PTEN IVS4 (rs 3830675) polymorphisms were determined using polymerase chain reaction-based restriction fragment length polymorphism (PCR–RFLP) in blood samples of 118 BC patients and 118 age-matched healthy controls. We found that the frequency of the Ile/Val genotype of HER2 Ile655Val gene was significantly higher in BC patients (p < 0.009; OR: 1,983 95 % CI: 1.181—3.328). The presence of ATCTT insertion (+/+) genotype at downstream of exon 4 in intron 4 of PTEN IVS4 gene was also associated with 1.83 fold decreased risk of BC development (p < 0.033; OR: 1.83, 95 % CI: 1.11—3.03). Analysis on clinico-pathological parameters showed neither HER2 Ile655Val nor PTEN IVS4 genotypes were not associated with any of the variables (p > 0.05).In conclusion, our findings suggest that the Ile/Val genotype of HER2 and ATCTT insertion (+/+) genotype of PTEN IVS4 gene may play an important role as genetic markers for breast cancer risk, but both genes genotypes may not be useful for predicting tumor prognosis in Turkish population.  相似文献   
82.

Background

Hydroxymethylglutaryl-Coenzyme A Reductase (HMGCR) catalyzes the rate-limiting step of cholesterol biosynthesis. This enzyme is the target of the widely available cholesterol lowering statins. In this population-based case–control study, the frequencies of -911 C>A polymorphism (rs3761740) of the HMGCR gene in patients with coronary heart disease (CHD) and healthy subjects were investigated and the correlations between the different genotypes and hypercholesterolemia with cardiovascular risk factors were analyzed.

Methods

The HMGCR genotypes were determined in 365 patients with CHD and 365 controls by PCR–RFLP assay. Anthropometric measurements were measured in all participants.

Results

There was no significant difference in the genotype frequencies of the HMGCR polymorphism between the male subjects of both patient and control groups, however, the HMGCR-CC genotype was found to be more frequent in female patients with CHD than female controls (p = 0.002). The HMGCR-CC genotype showed higher total-cholesterol (TC) and LDL-cholesterol (LDL-C) levels than the CA + AA genotypes in male CHD patients (p = 0.018). Due to this significant sex interaction, a multivariate analysis was conducted on the patient group. In the multivariate logistic regression analysis, the HMGCR-CC genotype was significantly associated with age < 55 (OR = 2.837, p = 0.001) and TC ≥ 5.18 mmol/L (OR = 1.970, p = 0.027) in male subjects. However, this association was not observed in female patients (p > 0.05). This analysis confirmed that the HMGCR-CC genotype was associated with elevated TC levels in male CHD patients with age < 55 years.

Conclusion

These results suggest that age and sex modify the contribution of the HMGCR-911 polymorphism to fasting serum TC, LDL-C levels and risk of CHD.  相似文献   
83.
Lack of requisite genetic variation in cultivated species has necessitated systematic collection, documentation and evaluation of wild Cicer species for use in chickpea variety improvement programs. Cicer arietinum has very narrow genetic variation, and the use of a wild relative in chickpea breeding could provide a good opportunity for increasing the available genetic variation of cultivated chickpea. Genetic diversity and the relationship of 71 accessions, from the core area of chickpea origin and domestication (Southeastern Turkey), belonging to five wild annual species and one cultivated species (Cicer arietinum) were analysed using iPBS-retrotransposon and ISSR markers. A total of 136 scorable bands were detected using 10 ISSR primers among 71 accessions belonging to 6 species, out of which 135 were polymorphic (99.3 %), with an average of 13.5 polymorphic fragments per primer, whereas iPBS detected 130 bands with 100 % polymorphism with an average of 13.0 bands per primer. C. echinospermum and C. pinnatifidum were the most diverse among species, whereas C. arietinum exhibited lower polymorphism. The average polymorphism information contents (PIC) value for both marker systems was 0.91. The clustering of the accessions and species within groups was almost similar, when iPBS and ISSR NeighborNet (NNet) planar graphs were compared. Further detailed studies are indispensable in order to collect Cicer germplasm, especially C. reticulatum, from southeastern Turkey particularly, from Karacada? Mountain for preservation, management of this species, and to study their genetic diversity at molecular level. This study also demonstrates the utility and role of iPBS-retrotransposons, a dominant and ubiquitous part of eukaryotic genomes, for diversity studies in wild chickpea and in cultivated chickpea.  相似文献   
84.
Tuna  Esin  Ersoy  Yeliz Emine  Bulut  Pelin  Ozdemir  Filiz  Buyru  Nur 《Molecular biology reports》2020,47(3):1605-1612
Molecular Biology Reports - Breast cancer, which is the most common type of cancer among women, is a heterogenous disease. It results from progressive accumulation of genetic and epigenetic...  相似文献   
85.
Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17 females, 13 males, mean age 33.53 ± 9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised control group (21 females, ten males with a mean age 33.93 ± 7.39 years). Urine fluoride levels of chronic fluorosis patients were significantly higher than that of control subjects as expected (1.92 ± 0.10 mg/l vs. 0.41 ± 0.09 mg/l, respectively; P < 0.001). Serum Cu levels (89.14 ± 16.77 μg/dL vs. 102.69 ± 25.04 μg/dL, respectively, P = 0.017), serum Zn levels (77.98 ± 20.58 μg/dL vs. 94.57 ± 35.87μg/dL, respectively, P = 0.032), and serum Mg levels (1.92 ± 0.18 mg/dL vs. 2.07 ± 0.31 mg/dL, respectively, p = 0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg.  相似文献   
86.
Pollen plays an important role in the development and exacerbation of allergic diseases. We aimed to investigate the days with highest counts of the most allergenic pollens and to identify the meteorological factors affecting pollen counts in the atmosphere of Ankara, Turkey. Airborne pollen measurements were carried out from 2005 to 2008 with a Burkard volumetric 7-day spore trap. Microscope counts were converted into atmospheric concentrations and expressed as pollen grains/m3. Meteorological parameters were obtained from the State Meteorological Service. All statistical analyses were done with pollen counts obtained from March to October for each year. The percentages of tree, grass and weed pollens were 72.1% (n = 24,923), 12.8% (n = 4,433) and 15.1% (n = 5,219), respectively. The Pinaceae family from tree taxa (39% to 57%) and the Chenopodiaceae/Amaranthaceae family from weed taxa, contributed the highest percentage of pollen (25% to 43%), while from the grass taxa, only the Poaceae family was detected from 2005 to 2008. Poaceae and Chenopodiaceae/Amaranthaceae families, which are the most allergenic pollens, were found in high numbers from May to August in Ankara. In multiple logistic regression analysis, wind speed (OR = 1.18, CI95% = 1.02–1.36, P = 0.023) for tree pollen, daily mean temperature (OR = 1.10, CI95% = 1.04–1.17, P = 0.001) and sunshine hours (OR = 1.15, CI95% = 1.01–1.30, P = 0.033) for grass pollen, and sunshine hours (OR = 3.79, CI95% = 1.03–13.92, P = 0.044) for weed pollen were found as significant risk factors for high pollen count. The pollen calendar and its association with meteorological factors depend mainly on daily temperature, sunshine hours and wind speed, which may help draw the attention of physicians and allergic patients to days with high pollen counts.  相似文献   
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88.
The asymmetric distribution of phospholipids in membranes is a fundamental principle of cellular compartmentalization and organization. Phosphatidylethanolamine (PE), a nonbilayer phospholipid that contributes to organelle shape and function, is synthesized at several subcellular localizations via semiredundant pathways. Previously, we demonstrated in budding yeast that the PE synthase Psd1, which primarily operates on the mitochondrial inner membrane, is additionally targeted to the ER. While ER-localized Psd1 is required to support cellular growth in the absence of redundant pathways, its physiological function is unclear. We now demonstrate that ER-localized Psd1 sublocalizes on the ER to lipid droplet (LD) attachment sites and show it is specifically required for normal LD formation. We also find that the role of phosphatidylserine decarboxylase (PSD) enzymes in LD formation is conserved in other organisms. Thus we have identified PSD enzymes as novel regulators of LDs and demonstrate that both mitochondria and LDs in yeast are organized and shaped by the spatial positioning of a single PE synthesis enzyme.  相似文献   
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