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231.
Ozdemir HS Karadas F Pappas AC Cassey P Oto G Tuncer O 《Biological trace element research》2008,122(3):206-215
The objective of the present study is to calculate linear regressions between a mother and her child with respect to their
selenium concentration (ng/g) in the following traits: maternal blood and umbilical cord blood, maternal and child hair, maternal
milk and child umbilical cord blood, maternal milk and meconium, maternal blood plasma, and child meconium. The data were
collected at Research Hospital of the University of Yüzüncü Yıl from 30 pairs of mothers and their newborn baby. The mean
maternal serum Se level in 30 mothers was 68.52 ± 3.57 ng/g and cord plasma level was 119.90 ± 18.08 ng/g. The Se concentration
in maternal and neonatal hair was 330.84 ± 39.03 and 1,124.76 ± 186.84 ng/g, respectively. The Se concentration of maternal
milk at day 14 after delivery was determined as 68.63 ± 7.78 ng/g (n = 13) and the concentration of Se was 418.90 ± 45.49 ng/g (n = 22) for meconium of neonatal. There was no significant difference between maternal blood and milk Se levels. However, hair
Se concentration was significantly higher than milk and maternal blood Se level. For each trait comparison, the average absolute
difference in log10-transformed Se concentration was calculated between a mother and her child. The observed average absolute difference was
compared with a test distribution of 1,000 resampled bootstrap averages where the number of samples was maintained but the
relationship between a mother and her child was randomized among samples (α = 0.05). 相似文献
232.
Randomly Amplified Polymorphic DNA markers (RAPD) were used to assess the hybrid identity of individuals sampled as Phlomis × termessi Davis. Out of 95 primers screened, 11 primers produced reproducible amplification patterns used for discrimination of P. × termessi and their parents. Eleven primers produced 81 bands. Forty two percent of the RAPD bands existed in parents. Of the 54 bands
found in P. lycia, 19 were found only in this species and 7 of these were monomorphic. Similarly, of 57 RAPD bands observed in P. bourgaei, 18 were found only in P. bourgaei and 6 of these were monomorphic. Among hybrid individuals, 35 of the 73 markers were monomorphic. Fifteen of these existed
in individual parents showing that parents were homozygous for these markers. Of the 35 monomorphic bands observed among hybrid
individuals, 5 were present in the samples of one of the parents and completely absent from the samples of the other; therefore,
additive inheritance is indicated. Of the 5 additive bands, 1 was inherited from P. bourgaei and 4 were inherited from P. lycia. Among 38 polymorhic markers observed in hybrid individuals, 9 were new and hybrid-specific. Pollen fertility was also investigated.
Mean pollen fertility for P. lycia and P. bourgaei was 93% and 97% respectively. However, mean pollen fertility for hybrids was 65% (±10.5). 相似文献
233.
Bedia Palabiyik Semian Karaer Nazli Arda Sidika Erturk Toker Guler Temizkan Steven Kelly Aysegul Topal Sarikaya 《Biologia》2008,63(3):450-454
Heterologous expression systems can be utilized to great advantage in the study of cytochrome P450 enzymes. P450 3A4 is one
of the major forms of cytochrome P450 found in liver. It is also involved in the metabolism of numerous widely used drugs
and xenobiotics. In the present study human liver cytochrome P450 3A4 gene was transferred into the fission yeast Schizosaccharomyces pombe via two different S. pombe expression vectors carrying thiamine repressible promoter — nmt1 (pREP42) and constitutive promoter — adh1 (pART1). Heterologously expressed cytochrome P450 3A4 was detected in the cells grown in minimal (EMM) or rich medium (YEL)
containing 0.5% (w/v) glucose. A typical cytochrome P450 peak for 3A4 was observed at 448 nm in microsomal fraction. The presence
of heterologous expression of 3A4 form was also determined by SDS-PAGE and it molecular mass was identified as 52 kDa. The
enzyme activity was confirmed by HPLC analysis, using testosterone as substrate. 相似文献
234.
Oxidative stress causes damage to proteins, lipids and nucleic acids, and thereby compromises cell viability. Some of the
oxidative stress markers in an eukaryotic model organism, fission yeast Schizosaccharomyces pombe, were evaluated in this study. Intracellular oxidation, protein carbonyls, lipid peroxidation and reduced glutathione (GSH)
levels were investigated in H2O2-treated and non-treated control cells. It was observed that increased H2O2 concentration proportionally lowered the cell number and increased the intracellular oxidation, lipid peroxidation and protein
carbonyl levels in S. pombe. A dose-dependent decrease in GSH level was also detected. The fission yeast S. pombe is best known for its contribution to understanding of eukaryotic cell cycle control. S. pombe displays a different physiology from Saccharomyces cerevisiae in several ways and is thus probably more closely related to higher eukaryotes. The purpose of this study was to provide
some data about the effects of hydrogen peroxide on the proteins and lipids in the fission yeast. The data obtained here is
expected to constitute a basis for the further studies on redox balance and related processes in yeast and mammalian cells. 相似文献
235.
Lindholm J Guitart-Masip M Hassankhali H Landgren S Nicoleau C Giménez-Llort L Terenius L Ogren SO Johansson B 《Neurochemical research》2008,33(10):2062-2069
In search for the substrate of naltrexone and acamprosate action on alcohol craving, we investigated the effects of ethanol
alone and combined with naltrexone or acamprosate on expression of nerve growth factor-inducible clone A (NGFI-A; zif268). In Experiments 1 and 3, alcohol (2 g/kg) alone or in combination with naltrexone (15 mg/kg) or acamprosate (300 mg/kg)
was injected intraperitoneally into mice. In Experiment 2, treatment was nor-BNI (0.5 mg/kg) to investigate whether the effect
of naltrexone involved blockade of κ-opioid receptors. Both ethanol and naltrexone alone induced NGFI-A in the central amygdala,
but not in several other areas; these effects were additive. However, acamprosate alone or in combination with ethanol had
no effect on NGFI-A mRNA, while nor-BNI induced NGFI-A mRNA in the basolateral amygdala. The central amygdala appears to be
an important target of both alcohol and naltrexone. Acamprosate may not share the site of action with naltrexone despite being
used for the same therapeutic purpose.
Special issue article in honor of Dr.Ji-Sheng Han. 相似文献
236.
Korkmaz A Oter S Sadir S Topal T Uysal B Ozler M Ay H Akin A 《Neurochemical research》2008,33(1):160-166
Hyperbaric oxygen (HBO) is known to cause oxidative stress in several organs and tissues. Due to its high rate of blood flow
and oxygen consumption, the brain is one of the most sensitive organs to this effect. The present study was performed to elucidate
the relation of HBO exposure time to its oxidative effects in rats’ brain cortex tissue. For this purpose, 49 rats were randomly
divided into five groups. Except the control group, study groups were subjected to three atmospheres HBO for 30, 60, 90, and
120 min. Their cerebral cortex layer was taken immediately after exposure and used for analysis. Thiobarbituric acid reactive
substances (TBARS), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and nitrate–nitrite (NOX) levels were determined. TBARS and SOD levels were found to increase in a time-dependent manner. GSH-Px activity reflected
an inconsistent course. NOX levels were found to be increased only in the 120 min exposed group. The results of this study suggests that HBO induced
oxidative effects are strongly related with exposure time. 相似文献
237.
The present study included 223 E. coli strains isolated from homemade white cheeses and was undertaken to determine the prevalence of extended spectrum β-lactamases
(ESBL)-producing strains and antibiotic susceptibility. ESBL production was detected using three methods: the NCCLS disk diffusion
test, the double disk synergy test and the NCCLS confirmatory test. By the disk diffusion test, 48% isolates were determined
as potential ESBL producers. ESBL production by the double disk test and the phenotypic confirmatory test was found to be
16.1 and 9.9%, respectively. Susceptibility of all isolates against 16 antimicrobials was tested by the disk diffusion method.
All strains were imipenem- and cefepime-susceptible. Susceptibility of E. coli to ceftazidime, ceftriaxon, cefotaxime and aztreonam was found to be 93.7, 96.4, 81.2, 90.6%, respectively. The least effective
antibiotics were ampicillin with a rate of 68.6% and cefuroxime with a rate of 69.1%. 相似文献
238.
Özge Özden William M. Ciesla Wayne J. Fuller David J. Hodgson 《Biodiversity and Conservation》2008,17(12):2821-2832
We analysed the influence of contemporary geography on butterfly diversity for islands in the Mediterranean Basin. We found
that island size and distance from the mainland has a significant effect on the number of species. We also used butterflies
as an indicator group to identify the importance of forest habitats for biodiversity conservation in the island of Cyprus.
To understand the relative importance of local vegetation characteristics of butterflies in the Pentadaktylos mountains transect
counts were used to assess the abundance and butterfly diversity in two different forest types. A total of 1,602 butterflies
and 23 species were recorded during this research. We observed highly significant effects of forest type on abundance and
species richness of butterflies. For example, number of butterflies was significantly higher in old forest than young pine
forest. Also, the abundance of endemic butterflies was highest in old forest habitats. Therefore, the survival of the majority
of endemic butterflies in Cyprus may depend on conservation of old forests and their understorey plants. 相似文献
239.
Leitner F Krallinger M Rodriguez-Penagos C Hakenberg J Plake C Kuo CJ Hsu CN Tsai RT Hung HC Lau WW Johnson CA Saetre R Yoshida K Chen YH Kim S Shin SY Zhang BT Baumgartner WA Hunter L Haddow B Matthews M Wang X Ruch P Ehrler F Ozgür A Erkan G Radev DR Krauthammer M Luong T Hoffmann R Sander C Valencia A 《Genome biology》2008,9(Z2):S6
We introduce the first meta-service for information extraction in molecular biology, the BioCreative MetaServer (BCMS; http://bcms.bioinfo.cnio.es/). This prototype platform is a joint effort of 13 research groups and provides automatically generated annotations for PubMed/Medline abstracts. Annotation types cover gene names, gene IDs, species, and protein-protein interactions. The annotations are distributed by the meta-server in both human and machine readable formats (HTML/XML). This service is intended to be used by biomedical researchers and database annotators, and in biomedical language processing. The platform allows direct comparison, unified access, and result aggregation of the annotations. 相似文献
240.
In this study, the cytogenetic response to lead exposure in storage battery manufacturing workers carrying different alleles of delta-aminolevulinic acid dehydratase (ALAD 1 and ALAD 2) was evaluated. The cytogenetic response was measured by analysis of the frequency of sister chromatid exchange (SCE) and the number of high-frequency cells (HFCs) in peripheral blood lymphocytes from workers occupationally exposed to lead. A total of 71 voluntary male workers were enrolled in the study. According to our genotype analysis, 50 workers had the ALAD 1-1 genotype and 21 workers had the ALAD 1-2 genotype. In spite of the statistically insignificant difference in mean values of SCE per cell between ALAD 1-1 and ALAD 1-2 workers, the percentage of HFC (HFC (%)) was statistically (chi2-test, P<0.05) higher in ALAD 1-1 workers. The control group was selected among voluntary male office workers (n = 20) and genotyping was also performed for this group in order to rule out the possibility that ALAD 1-1 subjects had a higher HFC (%) than ALAD 1-2 carriers, independent of the exposure to lead. Accordingly, 11 control workers had the ALAD 1-1 genotoype and 9 workers had ALAD 1-2. The differences in mean values of SCE per cell and HFC (%) were not statistically significant when the two genotypes in the control group were compared. On the basis of this result we suggest that ALAD 1-1 subjects might be more susceptible to cytogenetic effects of lead exposure than ALAD 1-2 subjects. There were no ALAD 2-2 subjects in the exposed and control groups. 相似文献