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111.
Al-Saleh E Nandakumaran M Al-Harmi J Sadan T Al-Enezi H 《Biological trace element research》2006,113(2):113-123
Obesity is well known to be a contributory risk factor for several disease states, including diabetes mellitus. Further, obese
women are more prone to have babies born with congenital abnormalities. Paucity of data on maternal-fetal disposition of essential
trace elements in obese pregnancies prompted us to undertake this study. Maternal venous and umbilical arterial and venous
samples were collected from obese patients (body mass index >30) and control pregnant women (body mass index <25) at time
of spontaneous delivery or cesarean sections and concentrations of essential trace elements such as Cu, Fe, Mo, Se, and Zn
determined in various samples by atomic absorption spectrophotometry. Activities of antioxidant enzymes, superoxide dismutase,
glutathione peroxidase, and total antioxidant activity in maternal and umbilical blood were assessed using appropriate reagent
kits. Maternal-fetal disposition and exchange parameters of elements studied were assessed using established critieria. Concentrations
of Cu, Fe, Mo, Se, and Zn in the serum of control pregnant women at time of delivery averaged 2232.6, 2398.1, 10.9, 108.9,
and 661.9 μg/L, respectively, whereas in the obese group, the values of the above elements averaged 2150.3, 2446.8, 12.6,
96.8, and 838.9 μg/L, respectively. Umbilical vein/maternal vein ratios of Cu, Fe, Mo, Se, and Zn in the control group averaged
0.29, 1.93, 1.06, 0.76, and 1.12, respectively, whereas in the obese group, their fetal-maternal ratios averaged 0.32, 2.23,
1.06, 0.78, and 1.53, respectively. The Cu:Zn ratio in the maternal vein of the obese group (3.60±0.20) was significantly
lower (Student's t-test; p<0.05) than that of the controls (2.50±0.19); however, Cu:Fe ratio (1.04±0.08 vs 1.02±0.09) was not significantly different
(Student's t-test; p>0.05) in the two groups. Varying differences were noted in the case of antioxidant enzyme activities between the control
and study groups. We conclude that obesity is associated with alterations in maternal-fetal disposition of some essential
trace elements and antioxidant enzyme status and that these alterations could pose a potential health risk for the mother
as well as the fetus. 相似文献
112.
Tawfik HE Cena J Schulz R Kaufman S 《American journal of physiology. Heart and circulatory physiology》2008,295(4):H1736-H1742
Multiparity is associated with increased risk of cardiovascular disease. We tested whether multiparity induces oxidative stress in rat vascular tissue. Coronary arteries and thoracic aorta were isolated from multiparous and age-matched virgin rats. Relaxation to ACh and sodium nitroprusside (SNP) was measured by wire myography. We also tested the effect of the superoxide dismutase mimetic MnTE2PyP (30 microM), the NADPH oxidase inhibitor apocynin (10 microM), and the peroxynitrite scavenger FeTPPs (10 microM) on ACh-mediated relaxation in coronary arteries. Vascular superoxide anion was measured using the luminol derivative L-012 and nitric oxide (NO) generation by the Griess reaction. Multiparity reduced maximal response and sensitivity to ACh in coronary arteries [maximal relaxation (E(max)): multiparous 49+/-3% vs. virgins 95%+/-3%; EC(50): multiparous 135+/-1 nM vs. virgins 60+/-1 nM], and in aortic rings (E(max): multiparous 38+/-3% vs. virgins 79+/-4%; EC(50): multiparous 160+/-2 nM vs. virgins 90+/-3 nM). Coronary arteries from the two groups relaxed similarly to SNP. Superoxide anions formation was significantly higher in both coronary arteries (2.8-fold increase) and aorta (4.1-fold increase) from multiparous rats compared with virgins. In multiparous rats, incubation with MnTE2PyP, apocynin, and FeTPPs improved maximal relaxation to ACh (MnTE2PyP: 74+/-5%; vehicle: 41+/-5%; apocynin: 73+/-3% vs. vehicle: 41+/-3%; FeTPPs: 72+/-3% vs. vehicle: 46+/-3%) and increased sensitivity (EC(50): MnTE2PyP: 61+/-0.5 nM vs. vehicle: 91+/-1 nM; apocynin: 45+/-3 nM vs. vehicle: 91+/-6 nM; FeTPP: 131 +/- 2 nM vs. vehicle: 185+/-1 nM). Multiparity also reduced total nitrate/nitrite levels (multiparous: 2.5+/-2 micromol/mg protein vs. virgins: 7+/-1 micromol/mg protein) and endothelial nitric oxide synthase protein levels (multiparous: 0.53+/-0.1 protein/actin vs. virgins: 1.0+/-0.14 protein/actin). These data suggest that multiparity induces endothelial dysfunction through decreased NO bioavailability and increased reactive oxygen species formation. 相似文献
113.
We investigated the relationship between habit, population size, floral traits and natural fruit set levels of 23 tropical
orchid species of south-east Bangladesh. We showed that epiphytic orchids had lower fruit set levels than terrestrial species
and that habit explained much of the variation in floral traits among the orchids. We compared our results with data from
76 other species occurring in the study area and hypothesize that a suite of floral and population characteristics present
in tropical orchids combine in epiphytes to reduce their reproductive success. Characteristics which, in addition to their
habit, are associated with low reproductive success are small population size, small inflorescences, non-sectile pollinia
and self-incompatibility. Several of these characteristics were phylogenetically conserved and we predict that epiphytes might
therefore generally have lower fruit set levels than recorded in terrestrial species. Nectar rewards are uncommon in tropical
orchids and nectarless species have displays of larger flowers, which may represent an adaptation to increase pollinator attraction,
although other rewards such as oils, waxes and pseudo pollen may replace nectar. We suggest that, like many temperate orchids,
a high proportion of tropical orchids may lack floral rewards and be pollinated by deceit. 相似文献
114.
Excel Que Kristen L James Alisha R Coffey Tangi L Smallwood Jody Albright M Nazmul Huda Daniel Pomp Praveen Sethupathy Brian J Bennett 《Genetics》2021,218(3)
Genetic approaches in model organisms have consistently demonstrated that molecular traits such as gene expression are under genetic regulation, similar to clinical traits. The resulting expression quantitative trait loci (eQTL) have revolutionized our understanding of genetic regulation and identified numerous candidate genes for clinically relevant traits. More recently, these analyses have been extended to other molecular traits such as protein abundance, metabolite levels, and miRNA expression. Here, we performed global hepatic eQTL and microRNA expression quantitative trait loci (mirQTL) analysis in a population of Diversity Outbred mice fed two different diets. We identified several key features of eQTL and mirQTL, namely differences in the mode of genetic regulation (cis or trans) between mRNA and miRNA. Approximately 50% of mirQTL are regulated by a trans-acting factor, compared to ∼25% of eQTL. We note differences in the heritability of mRNA and miRNA expression and variance explained by each eQTL or mirQTL. In general, cis-acting variants affecting mRNA or miRNA expression explain more phenotypic variance than trans-acting variants. Finally, we investigated the effect of diet on the genetic architecture of eQTL and mirQTL, highlighting the critical effects of environment on both eQTL and mirQTL. Overall, these data underscore the complex genetic regulation of two well-characterized RNA classes (mRNA and miRNA) that have critical roles in the regulation of clinical traits and disease susceptibility 相似文献
115.
Ruaa Ali Muhammed Ali Jamal Mohammed Ridha Alshara Nabil Salim Saaid Tuwaij Huda Jameel Baker Al-khilkhali 《Reports of Biochemistry & Molecular Biology》2022,11(1):166
Background:Escherichia coli (E. coli) remains one of the leading agents of urinary tract infection (UTIs), it has become resistant to many drugs. Current work aimed to evaluate some chemical substances as antibacterial agents and molecular study of virulence factors associated with UTIs.Methods:This work involved 133 urine specimens obtained from females’ patients suffering from UTIs, Methods of well diffusion and disk diffusion were achieved to assay the effect of some chemical substances and antibiogram profiles toward Sulfamethoxazole-trimethoprim (SXT)-resistant E. coli respectively. Virulence genes were done based on the technique of Polymerase Chain Reaction (PCR).Results:The results recorded 49/133 (36.84%) E. coli among women suffering UTIs, 28/49 (57.14%) were resistant to SXT drug. imipenem, meropenem, and nitrofurantoin were recorded more effectively. Chemicals substances at the concentration 0.3 (g/ml) recorded percentages of inhibition, reaching 9.143±1.442, 15.36±0.5914, and 21.82±0.8699 for NaHCO3, Ch4c, and Viroxide Super™ respectively. PCR demonstrated that 28/28 (100%) of SXT-resistant E. coli isolates were harbored Sul-2, FeoB and PapC genes, while 14/28 (50%), 15/28 (53.57%), 19/28 (67.85%) and 26/28 (92.85%) in U250 (pet), FumC, Sul-1 and IutA genes, respectively. Sul-3 gene was not observed.Conclusion:Observed a high percentage of E. coli that were resistant to SXT drug, and having several virulence genes, poses a real threat, it requires a real pause to create substitutions to limit the spreading of this threat.Key Words: Chemical substance, PCR, SXT-resistant E. coli, UTIs 相似文献
116.
Serine 776 of ataxin-1 is critical for polyglutamine-induced disease in SCA1 transgenic mice 总被引:17,自引:0,他引:17
Polyglutamine-induced neurodegeneration in transgenic mice carrying the spinocerebellar ataxia type 1 (SCA1) gene is modulated by subcellular distribution of ataxin-1 and by components of the protein folding/degradation machinery. Since phosphorylation is a prominent mechanism by which these processes are regulated, we examined phosphorylation of ataxin-1 and found that serine 776 (S776) was phosphorylated. Residue 776 appeared to affect cellular deposition of ataxin-1[82Q] in that ataxin-1[82Q]-A776 failed to form nuclear inclusions in tissue culture cells. The importance of S776 for polyglutamine-induced pathogenesis was examined by generating ataxin-1[82Q]-A776 transgenic mice. These mice expressed ataxin-1[82Q]-A776 within Purkinje cell nuclei, yet the ability of ataxin-1[82Q]-A776 to induce disease was substantially reduced. These studies demonstrate that polyglutamine tract expansion and localization of ataxin-1 to the nucleus of Purkinje cells are not sufficient to induce disease. We suggest that S776 of ataxin-1 also has a critical role in SCA1 pathogenesis. 相似文献
117.
Bertrand Perroud Paymaan Jafar-Nejad William R. Wikoff Jennifer R. Gatchel Lu Wang Dinesh K. Barupal Juan Crespo-Barreto Oliver Fiehn Huda Y. Zoghbi Rima Kaddurah-Daouk 《PloS one》2013,8(8)
We have shown that lithium treatment improves motor coordination in a spinocerebellar ataxia type 1 (SCA1) disease mouse model (Sca1154Q/+). To learn more about disease pathogenesis and molecular contributions to the neuroprotective effects of lithium, we investigated metabolomic profiles of cerebellar tissue and plasma from SCA1-model treated and untreated mice. Metabolomic analyses of wild-type and Sca1154Q/+ mice, with and without lithium treatment, were performed using gas chromatography time-of-flight mass spectrometry and BinBase mass spectral annotations. We detected 416 metabolites, of which 130 were identified. We observed specific metabolic perturbations in Sca1154Q/+ mice and major effects of lithium on metabolism, centrally and peripherally. Compared to wild-type, Sca1154Q/+ cerebella metabolic profile revealed changes in glucose, lipids, and metabolites of the tricarboxylic acid cycle and purines. Fewer metabolic differences were noted in Sca1154Q/+ mouse plasma versus wild-type. In both genotypes, the major lithium responses in cerebellum involved energy metabolism, purines, unsaturated free fatty acids, and aromatic and sulphur-containing amino acids. The largest metabolic difference with lithium was a 10-fold increase in ascorbate levels in wild-type cerebella (p<0.002), with lower threonate levels, a major ascorbate catabolite. In contrast, Sca1154Q/+ mice that received lithium showed no elevated cerebellar ascorbate levels. Our data emphasize that lithium regulates a variety of metabolic pathways, including purine, oxidative stress and energy production pathways. The purine metabolite level, reduced in the Sca1154Q/+ mice and restored upon lithium treatment, might relate to lithium neuroprotective properties. 相似文献
118.
The gene for autosomal dominant spinocerebellar ataxia (SCA1) maps telomeric to the HLA complex and is closely linked to the D6S89 locus in three large kindreds 总被引:16,自引:12,他引:4 下载免费PDF全文
Huda Y. Zoghbi Carla Jodice Lodewijk A. Sandkuijl Thomas J. Kwiatkowski Alanna E. McCall Sally A. Huntoon Patrizia Lulli Maria Spadaro Michael Litt Howard M. Cann Marina Frontali Luciano Terrenato 《American journal of human genetics》1991,49(1):23-30
We studied three large kindreds with the HLA-linked form of spinocerebellar ataxia (SCA1) in order to localize the SCA1 locus on the short arm of chromosome 6 (6p). Two loci containing highly informative dinucleotide repeat sequences were used for linkage analysis. These two loci are D6S89, which is telomeric to the HLA region, and T complex-associated testes-expressed 1 (TCTE1), centromeric to HLA. Pairwise linkage analysis of SCA1 and D6S89 revealed a maximum lod score of 5.86 in the Houston SCA1 (HSCA1) kindred and of 8.08 in the Calabrian SCA1 (SCA1) kindreds, at recombination fractions of .050 and .022, respectively. A maximum pairwise lod score of 4.54 at a recombination frequency of .100 was obtained for SCA1 and TCTE1 in the HSCA1 kindred. No evidence for linkage was detected between TCTE1 and SCA1 in the CSCA1 kindreds. Multilocus linkage analysis of SCA1, HLA, and D6S89 in all three kindreds provided strong evidence for localization of the SCA1 locus telomeric to the HLA regions. However, multilocus linkage analysis of SCA1, HLA, and TCTE1 with HSCA1 family genotypes indicated the possibility of a location of the SCA1 locus centromeric to HLA. An analysis of HSCA1 recombinants in this region of chromosome 6 revealed relatively high recombination frequencies between HLA and each of the other two markers and relatively low frequencies between the latter and SCA1, predicting that the SCA1 locus would tend to segregate away from HLA together with D6S89 or TCTE1, as found with the three-point linkage analyses for this family.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
119.
120.
Highly informative dinucleotide repeat polymorphisms were identified at the T-complex-associated-testes-expressed-1 (TCTE1) locus on human chromosome 6p. Electrophoresis of single-stranded DNA on native gels facilitated the analysis of the dinucleotide polymorphisms. Linkage mapping positions this marker midway between the centromere and HLA with recombination fractions as follows: D6Z1-0.21-TCTE1-0.24-HLA. Two-color fluorescence in situ hybridization places TCTE1 proximal to CRIL171 (D6S19). Together, linkage and in situ hybridization indicate that the order of the loci is D6Z1-D6S4-D6S90-TCTE1-D6S19-D6S29-HLA-telomere. A sequence tagged site (STS) was established, and three yeast artificial chromosome (YAC) clones were identified for the TCTE1 locus. 相似文献