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81.
The aim was to determine maternal weight gain and body composition during pregnancy and 3 months postpartum in women with uncomplicated singleton and twin pregnancies and in women with gestational diabetes (GDM) and gestational hypertension (GH). This prospective study includes four groups of subjects: those with an uncomplicated pregnancy (n = 32), those with a diagnosis of GH (n = 28), those with a diagnosis of GDM (n = 52), and those with twin pregnancy (n = 11). Their body compositions were estimated by a bioimpedance analysis and fasting lipids and glucose levels were determined during the pregnancy and 3 months after pregnancy. Women with GDM were 11.7 kg heavier than the reference group before pregnancy, whereas weight before pregnancy was not different in other investigated groups. Weight loss after delivery was attenuated in GH group. Percentage body fat remained elevated in women with GDM (34.1 ± 7.0%) and hypertension (31.5 ± 6.4%) at 3 months after pregnancy. Also their total cholesterol and low‐density lipoprotein (LDL)‐cholesterol levels as well as fasting glucose remained elevated in comparison to values of the reference group. In conclusion, women with hypertensive pregnancies, though not overweight before pregnancy, gain and retain excess gestational weight and this leads to metabolic abnormalities similar to those seen in women GDM. Thus, postpartum period appears to be critical for weight management and interventional programs are called for.  相似文献   
82.
This study presents the optimization of a microemulsion electrokinetic chromatographic (MEEKC) electrolyte solution by using UV detection and with the method, simultaneous separations of chemically, biochemically and pharmaceutically related anionic and cationic compounds. Representatives of the compound groups were from isoflavonoids, benzodiazepines, metanephrines, diuretics and peptide hormones. The MEEKC separations under basic conditions were first optimized using a two-component isoflavonoid mixture as the sample and an electrolyte containing 10 mM tetraborate as the main buffer (pH 9.5). The stable microemulsion phase was adjusted with various amounts of octane, 1-butanol and sodium dodecyl sulfate (SDS). An only acidified electrolyte solution used in the study was made of phosphoric acid (pH 1.8) containing octane, SDS and ethyl acetate. The analyses with isoflavonoids showed that electrophoretic mobilities of the investigated compounds were highly related to the concentrations of SDS and 1-butanol with linear and parabolic correlation, respectively. However, addition of octane gave linear correlation only at low concentrations. In most cases four to six structurally related compounds and even 13 diuretics with various polar properties were separated from each other in basic microemulsion medium. The acidified MEEKC electrolyte gave good resolution for anionic metanephrines.  相似文献   
83.
Parenteau J  Wellinger RJ 《Genetics》2002,162(4):1583-1594
Saccharomyces cerevisiae strains lacking the Rad27p nuclease, a homolog of the mammalian FEN-1 protein, display an accumulation of extensive single-stranded G-tails at telomeres. Furthermore, the lengths of telomeric repeats become very heterogeneous. These phenotypes could be the result of aberrant Okazaki fragment processing of the C-rich strand, elongation of the G-rich strand by telomerase, or an abnormally high activity of the nucleolytic activities required to process leading-strand ends. To distinguish among these possibilities, we analyzed strains carrying a deletion of the RAD27 gene and also lacking genes required for in vivo telomerase activity. The results show that double-mutant strains died more rapidly than strains lacking only telomerase components. Furthermore, in such strains there is a significant reduction in the signals for G-tails as compared to those detected in rad27delta cells. The results from studies of the replication intermediates of a linear plasmid in rad27delta cells are consistent with the idea that only one end of the plasmid acquires extensive G-tails, presumably the end made by lagging-strand synthesis. These data further support the notion that chromosome ends have differential requirements for end processing, depending on whether the ends were replicated by leading- or lagging-strand synthesis.  相似文献   
84.
Development of a bilayered living skin construct for clinical applications   总被引:5,自引:0,他引:5  
An in vitro construct of human skin (living skin equivalent, LSE) has been engineered using serially passaged human epidermal keratinocytes and human dermal fibroblasts with a matrix of type I collagen. Cells are obtained from neonatal foreskin. LSE is cast, cultured, and shipped in a single culture insert. The size and shape of theinsert determines thesize and shape of the LSE. The dermal matrix consists of dermal fibroblasts within a condensed collagen lattice. The overlying epidermis is developed at the air-liquid interface to generate a protective cornified layer. Serum was not necessaryfor development of the epidermis. LSE for graft (Graftskin) has handling characteristics similar to split-thickness skin allowing it to be meshed, stapled, and sutured. LSE was cryopreserved using 65% glycerol an rapid freezing. Viability and in vivo performance on athymic mice were similar to fresh LSE. Cells derived from human eccrine gland were able to invade and form tubules rudimentary appendages may be possible.  相似文献   
85.

Background

Geographic differences exist in the antibiotic resistance patterns of Helicobacter pylori. Personalized treatment regimens based on local or individual resistance data are essential. We evaluated the current status of H. pylori resistance in Ningxia, analyzed resistance-related factors, and assessed the concordance of phenotypic and genotypic resistance.

Methods

Strains were isolated from the gastric mucosa of patients infected with H. pylori in Ningxia and relevant clinical information was collected. Phenotypic antibiotic susceptibility assays (Kirby–Bauer disk diffusion) and antibiotic resistance gene detection (Sanger sequencing) were performed.

Results

We isolated 1955 H. pylori strains. The resistance rates of H. pylori to amoxicillin, levofloxacin, clarithromycin, and metronidazole were 0.9%, 42.4%, 40.4%, and 94.2%, respectively. Only five tetracycline-resistant and one furazolidone-resistant strain were identified. Overall, 3.3% of the strains were sensitive to all six antibiotics. Multidrug-resistant strains accounted for 22.9%, of which less than 20% were from Wuzhong. Strains isolated from women and patients with nonulcerative disease had higher rates of resistance to levofloxacin and clarithromycin. Higher rates of resistance to metronidazole, levofloxacin, and clarithromycin were observed in the older age group than in the younger age group. The kappa coefficients of phenotypic resistance and genotypic resistance for levofloxacin and clarithromycin were 0.830 and 0.809, respectively, whereas the remaining antibiotics showed poor agreement.

Conclusion

H. pylori antibiotic resistance is severe in Ningxia. Therefore, furazolidone, amoxicillin, and tetracycline are better choices for the empirical therapy of H. pylori infection in this region. Host sex, age, and the presence of ulcerative diseases may affect antibiotic resistance of the bacteria. Personalized therapy based on genetic testing for levofloxacin and clarithromycin resistance may be a future direction for the eradication therapy of H. pylori infection in Ningxia.  相似文献   
86.
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88.
(-)-Methadone acts as an agonist at opioid receptors. Both (+)- and (-)-enantiomers of methadone have been suggested to be potent non-competitive antagonists of alpha3beta4 neuronal nicotinic acetylcholine receptors (nAChRs). In the present study, we have examined interactions of methadone with nAChRs by using receptor binding assays, patch-clamp recording and calcium fluorometry imaging with SH-SY5Y cells naturally expressing alpha7 and alpha3* nAChR subtypes and SH-EP1-halpha7 cells heterologously expressing human alpha7 nAChRs. Methadone potently inhibited binding of [3H]methyllycaconitine to alpha7 nAChRs and that of [3H]epibatidine to alpha3* nAChRs. Methadone pretreatment induced up-regulation of epibatidine binding sites in SH-SY5Y cells. Using whole-cell patch-clamp recording, both isomers of methadone activated cation currents via mecamylamine-sensitive nAChRs in SH-SY5Y cells. Nicotine and both (+)- and (-)-methadone evoked increases in [Ca2+]i in both fluo-3AM loaded cell lines, and these effects were blocked by mecamylamine and by the alpha7 selective antagonist methyllycaconitine, suggesting effects of methadone as alpha7-nAChR agonist. Sensitivity of sustained nicotine and methadone effects to blockade by CdCl2, ryanodine and xestospongin-c implicates voltage-operated Ca2+ channels and intracellular Ca2+ stores as downstream modulators of elevated [Ca2+]i. Collectively, our results suggest that methadone engages in complex and potentially pharmacologically significant interactions with nAChRs.  相似文献   
89.
The Quebec population contains about six-million French Canadians, descended from the French settlers who colonized Nouvelle-France between 1608 and 1765. Although the relative genetic contribution of each of these founders is highly variable, altogether they account for the major part of the contemporary French-Canadian gene pool. This study was designed to analyze the role of this founder effect in the introduction and diffusion of the BRCA1 recurrent R1443X mutant allele. A highly conserved haplotype, observed in 18 French-Canadian families and generated using 17 microsatellite markers surrounding the BRCA1 locus, supports the fact that the R1443X mutation is a founder mutation in the Quebec population. We also performed haplotyping analysis of R1443X carriers on 19 other families from seven different nationalities; although the same alleles are shared for three markers surrounding the BRCA1 gene, distinct haplotypes were obtained in four families, suggesting multiple origins for the R1443X mutation. Ascending genealogies of the 18 French Canadian families and of controls were reconstructed on an average depth of 10 generations. We identified the founder couple with the highest probability of having introduced the mutation in the population. Based on the descending genealogy of this couple, we detected the presence of geographical concentration in the diffusion pattern of the mutation. This study demonstrates how molecular genetics and demogenetic analyses can complement each other to provide findings that could have an impact on public health. Moreover, this approach is certainly not unique to breast cancer genetics and could be used to understand other complex traits.Other members of the BCLC Haplotype Group involved in this study are listed in Appendix 1Other members of INHERIT BRCAs involved in this study are listed in Appendix 2H. Vézina and F. Durocher contributed equally to this work and should be regarded as joint first author  相似文献   
90.
Cerebrovascular diseases are one of the most common causes of epilepsy in adults, and the incidence of stroke-induced epileptogenesis is increasing as the population ages. The mechanisms that lead to stroke-induced epileptogenesis in a subpopulation of patients, however, are still poorly understood. Recent advances in inducing epileptogenesis in rodent focal ischemia models have provided tools that can be used to identify the risk factors and neurobiologic changes leading to development of epilepsy after stroke. Here we summarize data from models in which epileptogenesis has been studied after focal ischemia; photothrombosis, middle cerebral artery (MCA) occlusion with filament, and endothelin-1-induced MCA occlusion. Analysis of the data indicates that neurobiologic changes occurring during stroke-induced epileptogenesis share some similarities to those induced by status epilepticus or traumatic brain injury. Special issue dedicated to Dr. Simo S. Oja  相似文献   
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