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31.
The endothelial nitric oxide synthase (eNOS) gene is responsible for constitutive nitric oxide synthesis and arterial vasodilatation. Recently two polymorphisms, the 27-bp repeat sequence in intron 4 and the Glu298Asp substitution in exon 7 of the eNOS gene have been reported to be related to coronary heart disease (CHD). We screened these polymorphisms of the eNOS gene in 308 unrelated nondiabetic subjects with CHD, in 251 unrelated patients with type 2 diabetes with CHD, and in 110 randomly selected healthy subjects without CHD. The 4a and Asp298 allele frequencies of the eNOS gene were 0.19 and 0.36 in nondiabetic patients with CHD, 0.21 and 0.27 in type 2 diabetic patients with CHD, and 0.16 and 0.31 in nondiabetic subjects without CHD (n.s. between the groups). The Asp298 allele in exon 7 of the eNOS gene was not associated with elevated blood pressure in any of the study groups. Among type 2 diabetic patients with CHD the 4a allele in intron 4 of the eNOS gene was associated with elevated levels of systolic (P=0.035) and mean arterial blood pressure (P=0.040). In nondiabetic subjects these associations were not statistically significant. When all study groups were pooled in statistical analysis the 4a allele of the eNOS gene was associated with elevated diastolic (P=0.032) and mean (P=0.030) arterial blood pressure even after adjustment for confounding factors. We conclude that the 4a allele of the eNOS gene is not associated with CHD or type 2 diabetes, but that it is related to elevated blood pressure levels particularly among type 2 diabetic patients with CHD.  相似文献   
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Objective

Aurora-A is a potential oncogene and therapeutic target in ovarian carcinoma. It is involved in mitotic events and overexpression leads to centrosome amplification and chromosomal instability. The objective of this study was to evaluate the clinical significance of Aurora-A and DNA ploidy in serous ovarian carcinoma.

Methods

Serous ovarian carcinomas were analysed for Aurora-A protein by immunohistochemistry (n = 592), Aurora-A copy number by CISH (n = 169), Aurora-A mRNA by real-time PCR (n = 158) and DNA ploidy by flowcytometry (n = 440).

Results

Overexpression of Aurora-A was found in 27% of the tumors, cytoplasmic overexpression in 11% and nuclear in 17%. The cytoplasmic and nuclear overexpression were nearly mutually exclusive. Both cytoplasmic and nuclear overexpression were associated with shorter survival, high grade, high proliferation index and aberrant p53. Interestingly, only cytoplasmic expression was associated with aneuploidy and expression of phosphorylated Aurora-A. DNA ploidy was associated with poor patient outcome as well as aggressive clinicopathological parameters. In multivariate analysis, Aurora-A overexpression appeared as an independent prognostic factor for disease-free survival, together with grade, stage and ploidy.

Conclusions

Aurora-A protein expression is strongly linked with poor patient outcome and aggressive disease characteristics, which makes Aurora-A a promising biomarker and a potential therapeutic target in ovarian carcinoma. Cytoplasmic and nuclear Aurora-A protein may have different functions. DNA aneuploidy is a strong predictor of poor prognosis in serous ovarian carcinoma.  相似文献   
35.
Evolution of sleep and sleep EEG after hemispheric stroke   总被引:3,自引:0,他引:3  
The evolution of subjective sleep and sleep electroencephalogram (EEG) after hemispheric stroke have been rarely studied and the relationship of sleep variables to stroke outcome is essentially unknown. We studied 27 patients with first hemispheric ischaemic stroke and no sleep apnoea in the acute (1-8 days), subacute (9-35 days), and chronic phase (5-24 months) after stroke. Clinical assessment included estimated sleep time per 24 h (EST) and Epworth sleepiness score (ESS) before stroke, as well as EST, ESS and clinical outcome after stroke. Sleep EEG data from stroke patients were compared with data from 11 hospitalized controls and published norms. Changes in EST (>2 h, 38% of patients) and ESS (>3 points, 26%) were frequent but correlated poorly with sleep EEG changes. In the chronic phase no significant differences in sleep EEG between controls and patients were found. High sleep efficiency and low wakefulness after sleep onset in the acute phase were associated with a good long-term outcome. These two sleep EEG variables improved significantly from the acute to the subacute and chronic phase. In conclusion, hemispheric strokes can cause insomnia, hypersomnia or changes in sleep needs but only rarely persisting sleep EEG abnormalities. High sleep EEG continuity in the acute phase of stroke heralds a good clinical outcome.  相似文献   
36.
Sleep problems in young children are among the most common concerns reported to paediatricians. Sleep is thought to have important regulatory functions, and sleep difficulties in early childhood are linked to several psychosocial and physiological problems. Moreover, several prenatal factors have been found to influence infants’ sleep. Among them, most of the studies have been focused on maternal prenatal depression and/or anxiety as potential risk factors for sleep problems in childhood, whereas other relevant psychological factors during pregnancy have not received as much attention. Therefore, we aimed to examine the effect of several psychiatric maternal risk factors during pregnancy (i.e. symptoms of anxiety, depression, insomnia, alcohol use, seasonality, attention deficit and hyperactivity disorder and/or stressful life events) on the onset of some sleep problems related to sleep quality and sleep practices in 3‐month‐old infants. We examined 1,221 cases from a population‐based birth cohort, with subjective measures during pregnancy in mothers, and at 3 months after birth in the infants. The findings showed that all the maternal risk factors during pregnancy, except for symptoms of alcoholism and sleepiness, were related to sleep difficulties in infants. Interestingly, attention deficit and hyperactivity disorder symptomatology in mothers during pregnancy was the only variable that predicted more than two sleeping difficulties (i.e. long sleep‐onset latency, co‐sleeping with parents and irregular sleeping routines) at 3 months old. Our results highlight the relevance of maternal risk factors during pregnancy, and not only prenatal depression and/or anxiety, as variables to be considered when examining sleep difficulties in infants.  相似文献   
37.
Cholinergic basal forebrain structures are implicated in cortical arousal and regulation of the sleep–wake cycle. Cholinergic neurones are innervated by noradrenergic terminals, noradrenaline excites them via alpha‐1 receptors and microinjection of noradrenaline into the basal forebrain enhances wakefulness. However, it is not known to what extent the cholinergic versus non‐cholinergic basal forebrain projection neurones contribute to the arousing effects of noradrenaline. To elucidate the roles of cholinergic basal forebrain structures we administered methoxamine, an alpha‐1‐adrenergic agonist into the basal forebrain, in intact animals and again after selective destruction of the basal forebrain cholinergic cells by 192 IgG‐saporin. In eight male Han–Wistar rats implanted with electroencephalogram/electromyogram electrodes, a microdialysis probe targeted into the basal forebrain was perfused with artificial cerebrospinal fluid for 6 h on a baseline day, and with cerebrospinal fluid in the first and with methoxamine in the second 3‐h period of the subsequent day. The sleep–wake activity was recorded for 24 h on both days. Saporin was then injected into the basal forebrain and 2 weeks later the same experimental schedule (with cerebrospinal fluid and methoxamine) was repeated. In the intact animals, methoxamine exhibited a robust arousing effect and non‐rapid eye movement (NREM) and REM sleep was suppressed. Lesioning of the basal forebrain cholinergic neurones abolished almost completely the NREM sleep‐suppressing effect of methoxamine, whereas the REM sleep‐suppressing effect remained intact. Thus, the basal forebrain cholinergic neurones mediate, at least in part, cortical arousal and non‐REM sleep‐suppression, but they are not involved in the REM sleep‐suppressing effects of noradrenaline.  相似文献   
38.
Sprout-borne Salmonella outbreaks in Finland have increased during the last 10 years. The latest two were caused by Salmonella enterica serovar Bovismorbificans (antigenic structure 6,8:r:1,5) in 1994 and S. enterica serovar Stanley (4,5, 12:d:1,2) in 1995. In this study, the restriction fragment length polymorphism of genomic DNA after pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance profiles of the outbreak and nonoutbreak strains were compared. In each separate outbreak, the PFGE patterns of the outbreak strains (40 strains of S. enterica serovar Bovismorbificans and 28 strains of S. enterica serovar Stanley) after digestion of genomic DNA with restriction enzyme XbaI were indistinguishable from each other but differed clearly from those of the nonoutbreak strains (26 strains of S. enterica serovar Bovismorbificans and 40 strains of S. enterica serovar Stanley). The restriction enzyme XhoI did not differentiate the outbreak and nonoutbreak strains. The S. enterica serovar Stanley strains associated with the outbreak also had a unique antimicrobial resistance pattern, whereas all S. enterica serovar Bovismorbificans strains, both outbreak and nonoutbreak strains, were sensitive to all antimicrobial agents tested. Thus, the molecular typing confirmed that the S. enterica serovar Bovismorbificans outbreak isolates from humans and sprout salad were identical and strongly supported the epidemiological finding that S. enterica serovar Stanley outbreak isolates also originated from contaminated alfalfa seeds. It also confirmed that the sources of similar outbreaks in Sweden in 1994 caused by S. enterica serovar Bovismorbificans and in the United States in 1995 caused by S. enterica serovar Stanley and the source of the Finnish outbreaks were common.  相似文献   
39.
Increased expression of intercellular adhesion molecule 1 (ICAM1), a protein known to contribute to inflammatory responses, has been detected in the brain tissue of patients with Alzheimer's disease (AD) and animals modelled to mimic AD or Parkinson's disease (PD). ICAM1 may, thus, be implicated in the pathogenesis of these disorders. Our purpose was to investigate whether genetic variants of the ICAM1 gene have a role in causing susceptibility to AD and/or PD. We genotyped the E469K polymorphism of ICAM1 in 196 AD, 52 PD and 202 control patients of Finnish origin. The distributions of the genotype and allele frequencies of the polymorphism did not differ significantly between the AD, PD or the control patients. We therefore conclude that the E469K polymorphism of ICAM1 is not a risk factor for AD or PD.  相似文献   
40.
This study assessed the prediction power of experimental and computational models that are widely used to predict human passive intestinal absorption. The models evaluated included two cell lines, three artificial membrane models, in vivo rat experiments, and seven previously described computational quantitative structure property relationship models based on human absorption values. The data sets used in the assessment of the models were carefully chosen from the literature, and different models were compared using the same compounds to ensure objective results. Three of the computational models were found to be significantly more reliable in predicting human passive intestinal absorption than the artificial membrane models that have been developed for the prediction of passive intestinal absorption. Two of these computational models were found to be as reliable as the Caco-2 and the 2/4/A1 cell lines and, furthermore, one of the models was able to predict the absorption of a set of 65 drugs nearly as well as absorption studies in rats. The unexpectedly good prediction power of the simple computational models with high throughput makes them ideal tools in the early screening of drug candidates, whereas laborious cell culture models and animal studies can be useful in the later phases when detailed information about the transport mechanisms is needed.  相似文献   
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