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11.
Exonuclease 1 (Exo 1) is an important nuclease involved in mismatch repair system that contributes to maintain genomic stability,
to modulate DNA recombination, and to mediate cell cycle arrest. A guanine (G)/adenine (A) common single nucleotide polymorphism
at first position of codon 589 in Exo 1 gene determines a glutamic acid (Glu, E) to lysine (Lys, K) (K589E) aminoacidic substitution
which may alter cancer risk by influencing the activity of Exo 1 protein. Exo 1 K589E polymorphism has been studied in various
cancers, but its association with hepatocellular carcinoma (HCC) has yet to be investigated. To determine the association
of the Exo 1 K589E polymorphism with the risk of HCC development in a Turkish population, a hospital-based case–control study
was designed consisting of 224 subjects with HCC and 224 cancer-free control subjects matched for age, gender, smoking and
alcohol status. The genotype frequency of the Exo 1 K589E polymorphism was determined by using a polymerase chain reaction–restriction
fragment length polymorphism assay. Our data shows that the Lys/Lys genotype of the Exo 1 K589E polymorphism is associated
with increased risk of HCC development in this Turkish population [odds ratio (OR) = 2.15, 95% confidence interval (CI): 1.13–4.09,
P = 0.02]. Furthermore, according to stratified analysis, a significant association was observed between the homozygote Lys/Lys
genotype and HCC risk in the subgroups of male gender (OR = 2.67, 95% CI: 1.27–5.61, P = 0.009) and patients with non-viral-related HCC (OR = 3.14, 95% CI: 1.09–8.99, P = 0.03). Because our results suggest for the first time that the Lys/Lys homozygote genotype of Exo 1 K589E polymorphism
may be a genetic susceptibility factor for HCC in the Turkish population, further independent studies are required to validate
our findings in a larger series, as well as in patients of different ethnic origins. 相似文献
12.
Sümbül AT Akkız H Bayram S Bekar A Akgöllü E Sandıkçı M 《Molecular biology reports》2012,39(2):1639-1647
The tumor suppressor p53 gene plays a crucial role in preventing carcinogenesis through its ability to induce cell cycle arrest
and apoptosis following DNA damage and oncogene activation. A guanine (G)/cytosine (C) common single nucleotide polymorphism
(SNP) at second position of codon 72 in exon 4 of p53 gene determines a arginine (Arg) to proline (Pro) (Arg72Pro) aminoacidic
substitution within the proline-rich domain of p53 protein. Arg72 and Pro72 allele are different from a biochemical and biological
point of view and many reports suggest that they can modulate individual cancer susceptibility. To determine the association
of the p53 Arg72Pro polymorphism with the risk of hepatocellular carcinoma (HCC) development in a Turkish population, a hospital-based
case–control study was designed consisting of 119 subjects with HCC and 119 cancer-free control subjects matched for age,
gender, smoking and alcohol status. The genotype frequency of the p53 Arg72Pro polymorphism was determined by using a polymerase
chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Our data shows that the Pro/Pro genotype of the
p53 Arg72Pro polymorphism is associated with increased risk of HCC development in this Turkish population (OR = 3.20, 95%
CI: 1.24–8.22, P = 0.02). Furthermore, according to stratified analysis, a significant association was observed between the homozygote Pro/Pro
genotype and HCC risk in the subgroups of male gender (OR = 3.01, 95% CI: 1.14–7.97, P = 0.03) and patients with hepatitis B virus (HBV)-related HCC (OR = 4.04, 95% CI: 1.46–11.15, P = 0.007). Because our results suggest for the first time that the Pro/Pro homozygote of p53 Arg72Pro polymorphism may be
a genetic susceptibility factor for HCC (especially in the male gender and HBV-infected patients) in the Turkish population,
further independent studies are required to validate our findings in a larger series, as well as in patients of different
ethnic origins. 相似文献
13.
Pierre-Olivier Antoine Maeva J. Orliac Gokhan Atici Inan Ulusoy Erdal Sen H. Evren ?ubuk?u Ebru Albayrak Ne?e Oyal Erkan Aydar Sevket Sen 《PloS one》2012,7(11)
Background
Preservation of fossil vertebrates in volcanic rocks is extremely rare. An articulated skull (cranium and mandible) of a rhinoceros was found in a 9.2±0.1 Ma-old ignimbrite of Cappadocia, Central Turkey. The unusual aspect of the preserved hard tissues of the skull (rough bone surface and brittle dentine) allows suspecting a peri-mortem exposure to a heating source.Methodology/Principal Findings
Here we describe and identify the skull as belonging to the large two-horned rhinocerotine Ceratotherium neumayri, well-known in the late Miocene of the Eastern Mediterranean Province. Gross structural features and microscopic changes of hard tissues (bones and teeth) are then monitored and compared to the results of forensic and archaeological studies and experiments focusing on heating effects, in order to reconstruct the hypothetical peri-mortem conditions. Macroscopic and microscopic structural changes on compact bones (canaliculi and lamellae vanished), as well as partial dentine/cementum disintegration, drastic enamel-dentine disjunctions or microscopic cracks affecting all hard dental tissues (enamel, cementum, and dentine) point to continued exposures to temperatures around 400–450°C. Comparison to other cases of preservation of fossil vertebrates within volcanic rocks points unambiguously to some similarity with the 79 AD Plinian eruption of the Vesuvius, in Italy.Conclusions/Significance
A 9.2±0.1 Ma-old pyroclastic density current, sourced from the Çardak caldera, likely provoked the instant death of the Karacaşar rhino, before the body of the latter experienced severe dehydration (leading to the wide and sustainable opening of the mouth), was then dismembered within the pyroclastic flow of subaerial origin, the skull being separated from the remnant body and baked under a temperature approximating 400°C, then transported northward, rolled, and trapped in disarray into that pyroclastic flow forming the pinkish Kavak-4 ignimbrite ∼30 km North from the upper Miocene vent. 相似文献14.
Bülbül Hizel S Sanli C Bayar Muluk N Albayrak M Ozyazici A Apan A 《Biological trace element research》2008,124(2):129-134
The aim of this study was to investigate the effects of topotecan, a topoisomerase I-inhibiting anticancer agent, on hematologic
parameters and serum levels of trace elements. The study was conducted on three groups consisting of 16 and 18 rabbits in
the study groups and 15 rabbits in the control group. Rabbits in group I (n = 16) received high-dose topotecan intravenously (i.v.; 0.5 mg/kg once daily), while rabbits in group II (n = 18) received low-dose topotecan i.v. (0.25 mg/kg once daily) for 3 days. The 15 rabbits comprising the control group did
not receive topotecan. Serum samples were collected from each rabbit on the first day, before the treatment, and on the 15th
day of treatment. Erithrocytes, hemoglobin, white blood cell count, thrombocyte count, and trace elements such as selenium,
copper, lead, zinc, and cobalt were analyzed. Hemoglobin levels and erythrocyte counts were lower in both study groups than
in the control group. However, thrombocyte and leukocyte counts were similar in all three groups (p > 0.005). Serum trace element levels (copper, lead, zinc, and cobalt) did not differ significantly between groups. However,
serum selenium levels were significantly lower in both study groups than the control group (p < 0.001). The results revealed that topotecan treatment causes a decrease in erythrocyte counts and hemoglobin levels due
to bone marrow suppression, and these effects must be taken into account during treatment. In addition, selenium supplementation
might be helpful in cancer patients receiving topotecan to increase the effect of the chemotherapeutic agent. 相似文献
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Eduard A. Shuralev Nikolai D. Shamaev Malik N. Mukminov Kisaburo Nagamune Yuji Taniguchi Taizo Saito Katsuya Kitoh Marina I. Arleevskaya Anastasiya Yu. Fedotova Diana R. Abdulmanova Natalya M. Aleksandrova Marina A. Efimova Aynur I. Yarullin Anna R. Valeeva Kamil S. Khaertynov Yasuhiro Takashima 《Parasitology international》2018,67(2):112-114
Toxoplasmosis, a most common zoonosis, is caused by the protozoan parasite Toxoplasma gondii. However, there is little epidemiological information on T. gondii infections in humans and livestock animals in Russia. Therefore, in this study, the seroprevalence of T. gondii in goats in Russia was investigated. A total of 216 goats from 32 farms were investigated and 95 of them were seropositive for T. gondii. The difference in seroprevalence between the examined regions was not statistically significant. We next collected serum samples from 99 cats and 181 humans in Kazan city, the state capital of the Republic of Tatarstan, Russia, and examined their T. gondii seroprevalences. Thirty-nine of the 99 cat samples and 56 of the 181 human samples showed seropositivity. Logistical regression analysis revealed that the cat breeding history of the human subjects, but not their sex or age is a significant risk factor for T. gondii seropositivity. These findings suggest that the natural environment in Russia may be widely polluted with T. gondii oocysts shed by cats, and ingestion of these oocysts provides a major route for human infection with this parasite. 相似文献
17.
S. Mert Selimoglu Gurler Akpinar Aynur Karadenizli 《Preparative biochemistry & biotechnology》2017,47(1):94-99
Human cardiac troponin-I (cTnI) is one of the most sensitive and specific indicators, used in the diagnosis of myocardial infarction. To produce the protein efficiently, Escherichia coli and Pichia pastoris systems were used. Initial trials for the expression in E. coli were not successful, although different expression vectors with different promoters were tested. This led us to use P. pastoris for the expression. After several trials with two different expression strains of P. pastoris, it was concluded that P. pastoris was also not an optimal expression host for cTnI. Comprehensive analysis of the expression systems indicated that an efficient expression is only possible when the gene is optimized for expression in E. coli. For this purpose, the gene was optimized in-silico, but edited manually afterwards. It was synthesized and cloned into pQE-2 vector. Expression was performed using routine experimental conditions. Thus, cTnI could be efficiently expressed from the optimized gene in E. coli. The expression and purification were practical and may be used for commercial purposes since a total yield of 25µg highly pure protein per milliliter of culture could be obtained. The protein was in its ready-to-use form for many biological applications, including as a standard in diagnostic tests and an antigen for antibody production. 相似文献
18.
Conventionally stained, C- and Ag-NOR banded karyotypes of Guenther's vole, Microtus guentheri were studied from Turkey. The species possesses a karyotype of 2n = 54, NFa = 52 and NF = 54 in specimens from Kahramanmara? and Gaziantep provinces, whereas NF = 56 in females and NF = 55 in males were found in individuals from Kirikkale and Nev?ehir provinces. The X chromosome was a large acrocentric (NF = 54) or submetacentric (NF = 55, 56) while the Y chromosome was a small telocentric in all specimens examined. Blocks of constitutive heterochromatin were located in the pericentromeric areas of autosomes including the X chromosome. Nucleolar organizer regions (NORs) were located at the telomeric regions of the short arms of five acrocentric pairs and centromeric regions of two telocentric pairs in the Nev?ehir and Kirikkale specimens. 相似文献
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Seidl-Seiboth V Gruber S Sezerman U Schwecke T Albayrak A Neuhof T von Döhren H Baker SE Kubicek CP 《Journal of molecular evolution》2011,72(4):339-351
Hydrophobins are small proteins, characterised by the presence of eight positionally conserved cysteine residues, and are
present in all filamentous asco- and basidiomycetes. They are found on the outer surfaces of cell walls of hyphae and conidia,
where they mediate interactions between the fungus and the environment. Hydrophobins are conventionally grouped into two classes
(class I and II) according to their solubility in solvents, hydropathy profiles and spacing between the conserved cysteines.
Here we describe a novel set of hydrophobins from Trichoderma spp. that deviate from this classification in their hydropathy, cysteine spacing and protein surface pattern. Phylogenetic
analysis shows that they form separate clades within ascomycete class I hydrophobins. Using T. atroviride as a model, the novel hydrophobins were found to be expressed under conditions of glucose limitation and to be regulated
by differential splicing. 相似文献