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41.
Molecular evolution of coding and non-coding sequences of the growth hormone receptor (GHR) gene in the family Bovidae 总被引:1,自引:0,他引:1
The GHR gene exon 1A and exon 4 with fragments of its flanking introns were sequenced in twelve Bovidae species and the obtained sequences were aligned and analysed by the ClustalW method. In coding exon 4 only three interspecies differences were found, one of which had an effect on the amino-acid sequence--leucine 152 proline. The average mutation frequency in non-coding exon 1A was 10.5 per 100 bp, and was 4.6-fold higher than that in coding exon 4 (2.3 per 100 bp). The mutation frequency in intron sequences was similar to that in non-coding exon 1A (8.9 vs 10.5/100 bp). For non-coding exon 1A, the mutation levels were lower within than between the subfamilies Bovinae and Caprinae. Exon 4 was 100% identical within the genera Ovis, Capra, Bison, and Bos and 97.7% identical for Ovis moschatus, Ammotragus lervia and Bovinae species. The identity level of non-coding exon 1A of the GHR gene was 93.8% between species belonging to Bovinae and Caprinae. The average mutation rate was 0.2222/100 bp/MY and 0.0513/100 bp/MY for the Bovidae GHR gene exons 1A and 4, respectively. Thus, the GHR gene is well conserved in the Bovidae family. Also, in this study some novel intraspecies polymorphisms were found for cattle and sheep. 相似文献
42.
Analysis of variation at 10 polymorphic isoenzyme loci in 51 European populations of Pinus sylvestris both from its main continuous range and from isolated, marginal populations out of the continuous range, revealed differences in genetic structure. The highest genetic richness, measured as mean number of alleles per locus, was recorded for populations from the Iberian Peninsula, followed by those from Scotland and the Balkans. Marginal, isolated populations were characterized by much greater interpopulation variation than populations from the continuous range of the species. The highest mean observed heterozygosity was recorded for the Iberian populations. The highest gene flow was observed among populations in the continuous range of the species. The populations could be classified into five groups based on genetic similarities. Populations from the continuous range formed one group, those from Spain two groups, pines from Scotland one group and those from the Balkans one group. One population from Scotland was found to be most distinct from the other Scottish pines and was found to be grouped with the Balkan populations. The occurrence and frequencies of rare alleles in the populations showed a characteristic pattern, suggesting that populations from the Iberian Peninsula probably did not participate in the colonization of Europe by Pinus sylvestris after the last glaciation. In contrast, the migration of populations from the Balkan refugium into Central and Western Europe had a significant effect on the contemporary gene pools of populations of Pinus sylvestris in its continuous range. 相似文献
43.
Mazurek M Kowalczyk J Lenarczyk R Zielinska T Sedkowska A Pruszkowska-Skrzep P Swiatkowski A Sredniawa B Kowalski O Polonski L Strojek K Kalarus Z 《Cardiovascular diabetology》2012,11(1):78
ABSTRACT: BACKGROUND: Diabetes (DM) deteriorates the prognosis in patients with coronary heart disease. However, the prognostic value of different glucose abnormalities (GA) other than DM in subjects with acute myocardial infarction (AMI) treated invasively remains unclear. AIMS: To assess the incidence and impact of GA on clinical outcomes in AMI patients treated with percutaneous coronary intervention (PCI). METHODS: A single-center, prospective registry encompassed 2733 consecutive AMI subjects treated with PCI. In all in-hospital survivors (n = 2527, 92.5 %) without the history of DM diagnosed before or during index hospitalization standard oral glucose tolerance test (OGTT) was performed during stable condition before hospital discharge and interpreted according to WHO criteria. The mean follow-up period was 37.5 months. RESULTS: The incidence of GA was as follows: impaired fasting glycaemia - IFG (n = 376, 15 %); impaired glucose tolerance - IGT (n = 560, 22 %); DM (n = 425, 17 %); new onset DM (n = 384, 15 %); and normal glucose tolerance NGT (n = 782, 31 %). During the long-term follow-up, death rate events for previously known DM, new onset DM and IGT were significantly more frequent than those for IFG and NGT (12.3; 9.6 and 9.4 vs. 5.6 and 6.4 %, respectively, P < 0.05). The strongest and common independent predictors of death in GA patients were glomerular filtration rate < 60 ml/min/1,73 m^2 (HR 2.0 and 2.8) and left ventricle ejection fraction < 35 % (HR 2.5 and 1.8, all P < 0.05) respectively. CONCLUSIONS: Glucose abnormalities are very common in AMI patients. DM, new onset DM and IGT increase remote mortality. Impaired glucose tolerance bears similar long-term prognosis as diabetes. 相似文献
44.
Turner RM Lloyd-Jones M Anumba DO Smith GC Spiegelhalter DJ Squires H Stevens JW Sweeting MJ Urbaniak SJ Webster R Thompson SG 《PloS one》2012,7(2):e30711
Background
To estimate the effectiveness of routine antenatal anti-D prophylaxis for preventing sensitisation in pregnant Rhesus negative women, and to explore whether this depends on the treatment regimen adopted.Methods
Ten studies identified in a previous systematic literature search were included. Potential sources of bias were systematically identified using bias checklists, and their impact and uncertainty were quantified using expert opinion. Study results were adjusted for biases and combined, first in a random-effects meta-analysis and then in a random-effects meta-regression analysis.Results
In a conventional meta-analysis, the pooled odds ratio for sensitisation was estimated as 0.25 (95% CI 0.18, 0.36), comparing routine antenatal anti-D prophylaxis to control, with some heterogeneity (I 2 = 19%). However, this naïve analysis ignores substantial differences in study quality and design. After adjusting for these, the pooled odds ratio for sensitisation was estimated as 0.31 (95% CI 0.17, 0.56), with no evidence of heterogeneity (I 2 = 0%). A meta-regression analysis was performed, which used the data available from the ten anti-D prophylaxis studies to inform us about the relative effectiveness of three licensed treatments. This gave an 83% probability that a dose of 1250 IU at 28 and 34 weeks is most effective and a 76% probability that a single dose of 1500 IU at 28–30 weeks is least effective.Conclusion
There is strong evidence for the effectiveness of routine antenatal anti-D prophylaxis for prevention of sensitisation, in support of the policy of offering routine prophylaxis to all non-sensitised pregnant Rhesus negative women. All three licensed dose regimens are expected to be effective. 相似文献45.
Due to the variant functions that estrogens play in the regulation of reproduction, development of the mammary gland, growth
and differentiation of cells, estrogen receptors and their genes are considered as a candidates for the markers of production
and functional traits in farm animals, including cattle. In the earliest study, a 2853-bp bovine ER gene 5′-region was PCR
amplified and sequenced. Moreover, for the first time, a polymorphism was described within 5′ region of the bovine ERα gene—A/G
transition lying upstream at position 2591 from acceptor splice site +85, possibly within its promoter—which could be recognized
with RFLP-BglI. In other study we are found second polymorphism—A/G transition at position 1213 from acceptor splice site +85, located
in promoter for exon B. We have examined the specific mRNA expression of ERα in various genotypes using real-time RT-PCR.
We used four animals from each genotype group—AG, GG for BglI and AA, AG for SnaBI—to analyse liver ERα expression at the level of Real-time PCR. Liver samples were taken from the 16 young Friesian bulls
of the different ERα genotypes, slaughtered at the local abattoir. As shown by Real-Time PCR, on the livers of animals with
different genotype ERα mRNA for BglI polymorphism we didn’t found variability, but for SnaBI we have found variability between AG and AA genotypes. 相似文献
46.
Bocian W Sitkowski J Bednarek E Tarnowska A Kawecki R Kozerski L 《Journal of biomolecular NMR》2008,40(1):55-64
Here we present evidence that in water/acetonitrile solvent detailed structural and dynamic information can be obtained for
important proteins that are naturally present as oligomers under native conditions. An NMR-derived human insulin monomer structure
in H2O/CD3CN, 65/35 vol%, pH 3.6 is presented and compared with the available X-ray structure of a monomer that forms part of a hexamer
(Acta Crystallogr. 2003 Sec. D59, 474) and with NMR structures in water and organic cosolvent. Detailed analysis using PFGSE
NMR, temperature-dependent NMR, dilution experiments and CSI proves that the structure is monomeric in the concentration and
temperature ranges 0.1–3 mM and 10–30°C, respectively. The presence of long-range interstrand NOEs, as found in the crystal
structure of the monomer, provides the evidence for conservation of the tertiary structure. Starting from structures calculated
by the program CYANA, two different molecular dynamics simulated annealing refinement protocols were applied, either using
the program AMBER in vacuum (AMBER_VC), or including a generalized Born solvent model (AMBER_GB).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Wojciech Bocian contributed equally to this work. 相似文献
47.
Valery A. Isidorov Paweł Lech Anna Żółciak Magdalena Rusak Lech Szczepaniak 《Trees - Structure and Function》2008,22(4):531-542
An investigation was carried out of the composition of metabolites in pine seedlings tissues at the initial stages of the
infectious process caused by pathogenic fungi Armillaria ostoyae, which causes a root rot of trees and degradation of forest resources. With the help of successive extraction with organic
solvents of different polarity, more than 190 metabolites were extracted from the needles and roots of the seedlings and then
identified by GC–MS method. The composition of the extracts from control plants and those inoculated with Armillaria ostoyae were compared. It was established that part of secondary metabolites (glucosamines and free amino acids, carbohydrates raffinose
and trehalose) were present only in the tissues of inoculated plants. Possible roles of some of these compounds appearing
in the roots of seedlings infected with the fungus are also discussed in the paper. 相似文献
48.
The purpose of this work was to evaluate the effect of the nature of the ionizable end groups, and the solvent, on their acid-base properties in alanine-based peptides. Hence, the acid-base properties of three alanine-based peptides: Ac-KK-(A)(7)-KK-NH(2) (KAK), Ac-OO-(A)(7)-DD-NH(2) (OAD), Ac-KK-(A)(7)-EE-NH(2) (KAE), where A, D, E, K, and O denote alanine, aspartic acid, glutamic acid, lysine, and ornithine, respectively, were determined in water and in methanol by potentiometry. With the availability of these data, the ability of two theoretical methods to simulate pH-metric titration of those peptides was assessed: (i) the electrostatically driven Monte Carlo method with the ECEPP/3 force field and the Poisson-Boltzmann approach to compute solvation energy (EDMC/PB/pH), and (ii) the molecular dynamics method with the AMBER force field and the Generalized Born model (MD/GB/pH). For OAD and KAE, pK(a1) and pK(a2) correspond to the acidic side chains. For all three compounds in both solvents, the pK(a1) value is remarkably lower than the pK(a) of a compound modeling the respective isolated side chain, which can be explained by the influence of the electrostatic field from positively charged ornithine or lysine side chains. The experimental titration curves are reproduced well by the MD/GB/pH approach, the agreement being better if restraints derived from NMR measurements are incorporated in the conformational search. Poorer agreement is achieved by the EDMC/PB/pH method. 相似文献
49.
Miłosława Zowczak Maria Iskra Lech Torliński Szczepan Cofta 《Biological trace element research》2001,82(1-3):1-8
Several studies have shown that plasma copper concentrations are increased in various carcinomas. Zinc acts as a cellular
growth protector, including growth of neoplastic cells, and its deficiency was demonstrated to be involved in several stages
of malignant transformation. However, the usefulness of the serum zinc and copper determinations in cancer prevention, detection,
monitoring treatment, and prognosis requires further investigations. The aim of the present study was to compare the serum
copper and zinc levels in patients with cancer of the lung (PC), breast (BC), gastrointestinal tract (GIC), and gynecological
(GYNC) malignancy with progress of the disease. The results of the study have shown a significant increase in the mean total
serum Cu levels and the serum Cu/Zn ratio in all patient groups with cancer compared to a control group. Increased mean serum
concentrations and Cu/Zn ratios were found in the whole group (ALLC), and for the GIC and GYNC groups with local as well as
metastasized (Meta) disease in comparison with the control group. The mean serum concentrations of Zn were decreased only
in metastasized ALLC and GYNC groups. 相似文献
50.
Long-En Chen Kang Liu Wen-Ning Qi Elizabeth Joneschild Xiangling Tan Anthony V Seaber Jonathan S Stamler James R Urbaniak 《Journal of applied physiology》2002,92(2):559-566
This study investigated the dosage effects of nitric oxide synthase (NOS) inhibitor N(G)-monomethyl-L-arginine (L-NMMA) on intermittent pneumatic compression (IPC)-induced vasodilation in uncompressed upstream muscle and the effects of IPC on endothelial NOS (eNOS) expression in upstream muscle. After L-NMMA infusion, mean arterial pressure increased by 5% from baseline (99.5 +/- 18.7 mmHg; P < 0.05). Heart rate and respiratory rate were not significantly affected. One-hour IPC application on legs induced a 10% dilation from baseline in 10- to 20-microm arterioles and a 10-20% dilation in 21- to 40 microm arterioles and 41- to 70-microm arteries in uncompressed cremaster muscle. IPC-induced vasodilation was dose dependently reduced, abolished, or even reversed by concurrently infused L-NMMA. Moreover, expression of eNOS mRNA in uncompressed cremaster muscle was upregulated to 2 and 2.5 times normal at the end of 1- and 5-h IPC on legs, respectively, and the expression of eNOS protein was upregulated to 1.8 times normal. These increases returned to baseline level after cessation of IPC. The results suggest that eNOS plays an important role in regulating the microcirculation in upstream muscle during IPC. 相似文献