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Three 1AR subtypes have been cloned so far and are designated as 1a, 1b, and 1d. Organspecific distribution pattern and subtype-specific effects are known but not fully understood. To address a cell-type specific expression pattern in the heart we investigated expression pattern of 1AR subtypes on RNA and proteinlevel in heart tissue, cultured cardiomyocytes and nonmyocytes of the rat. Each 1ARsubtype mRNA was present in neonatal and adult rat heart culture but the relative distribution pattern was significantly different. While the 1aAR subtype is preferentially expressed in adult cardiomyocytes, the 1bAR subtype was preferentially expressed in the nonmyocyte cell fraction. The RTPCR results were confirmed by Westernblotting (1b) and immunocytochemical studies. Incubation with an 1agonist (phenylephrine) for 72 h led to a significant reduction of the 1bAR in neonatal heart cell culture on both mRNA and protein level. In contrast, incubation with an 1antagonist (prazosin) induced a 1.6 fold upregulation of the 1aAR mRNA without significant effects on radioligand binding and functional assay. The results indicate a distribution pattern of the 1AR subtype which is specific for cell type and ontogeny of the rat heart and may be regulated by adrenergic agents.  相似文献   
43.

Objectives

To study the course of ADHD during childhood and analyze possible personal and family predictor variables of the results.

Method

Sixty-one children with ADHD who were between 6 and 12 years old at the baseline assessment were evaluated 30 months later (mean age at baseline: 8.70 ± 1.97; mean age at follow-up: 10.98 ± 2.19). Status of ADHD in follow-up was identified as persistent (met DSM-IV-TR criteria according to parents’ and teachers’ ratings), contextually persistent (met ADHD criteria according to one informant, and there was functional impairment) and remitted ADHD (with subthreshold clinical symptomatology). Associated psychological disorders of the three groups were analyzed in the follow-up with the Conners'' Rating Scales. The groups were compared on ADHD characteristics (symptoms of ADHD and impairment), child psychopathology, executive functioning (EF; inhibition, working memory) and parenting characteristics (parental stress and discipline styles) at baseline.

Results

At the follow-up, 55.7% of the children continued to meet the DSM-IV-TR criteria for ADHD, 29.5% showed contextual persistence, and 14.8% presented remission of the disorder. The persistent and contextually persistent ADHD groups showed more associated psychological disorders. Inattention, oppositional problems, cognitive problems and impairment at baseline distinguished the remitted ADHD children from the persistent and contextually persistent ADHD children. Moreover, the persistent groups had significantly more emotional liability and higher parental stress than the group in remission, while no differences in EF where found among the groups.

Conclusions

ADHD children continue to present symptoms, as well as comorbid psychological problems, during adolescence and early adulthood. These findings confirm that persistence of ADHD is associated with child psychopathology, parental stress and impairment in childhood.  相似文献   
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Background

In translational cancer research, gene expression data is collected together with clinical data and genomic data arising from other chip based high throughput technologies. Software tools for the joint analysis of such high dimensional data sets together with clinical data are required.

Results

We have developed an open source software tool which provides interactive visualization capability for the integrated analysis of high-dimensional gene expression data together with associated clinical data, array CGH data and SNP array data. The different data types are organized by a comprehensive data manager. Interactive tools are provided for all graphics: heatmaps, dendrograms, barcharts, histograms, eventcharts and a chromosome browser, which displays genetic variations along the genome. All graphics are dynamic and fully linked so that any object selected in a graphic will be highlighted in all other graphics. For exploratory data analysis the software provides unsupervised data analytics like clustering, seriation algorithms and biclustering algorithms.

Conclusions

The SEURAT software meets the growing needs of researchers to perform joint analysis of gene expression, genomical and clinical data.  相似文献   
47.

Background

Although some epidemiologic studies found inverse associations between alcohol drinking and Parkinson's disease (PD), the majority of studies found no such significant associations. Additionally, there is only limited research into the possible interactions of alcohol intake with aldehyde dehydrogenase (ALDH) 2 activity with respect to PD risk. We examined the relationship between alcohol intake and PD among Japanese subjects using data from a case-control study.

Methods

From 214 cases within 6 years of PD onset and 327 controls without neurodegenerative disease, we collected information on "peak", as opposed to average, alcohol drinking frequency and peak drinking amounts during a subject's lifetime. Alcohol flushing status was evaluated via questions, as a means of detecting inactive ALHD2. The multivariate model included adjustments for sex, age, region of residence, smoking, years of education, body mass index, alcohol flushing status, presence of selected medication histories, and several dietary factors.

Results

Alcohol intake during peak drinking periods, regardless of frequency or amount, was not associated with PD. However, when we assessed daily ethanol intake separately for each type of alcohol, only Japanese sake (rice wine) was significantly associated with PD (adjusted odds ratio of ≥66.0 g ethanol per day: 3.39, 95% confidence interval: 1.10-11.0, P for trend = 0.001). There was no significant interaction of alcohol intake with flushing status in relation to PD risk.

Conclusions

We did not find significant associations between alcohol intake and PD, except for the daily amount of Japanese sake. Effect modifications by alcohol flushing status were not observed.  相似文献   
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iNKT cells are required for the induction of airway hyperreactivity (AHR), a cardinal feature of asthma, but how iNKT cells traffic to the lungs to induce AHR has not been previously studied. Using several models of asthma, we demonstrated that iNKT cells required the chemokine receptor CCR4 for pulmonary localization and for the induction of AHR. In both allergen-induced and glycolipid-induced models of AHR, wild-type but not CCR4-/- mice developed AHR. Furthermore, adoptive transfer of wild-type but not CCR4-/- iNKT cells reconstituted AHR in iNKT cell-deficient mice. Moreover, we specifically tracked CCR4-/- vs wild-type iNKT cells in CCR4-/-:wild-type mixed BM chimeric mice in the resting state, and when AHR was induced by protein allergen or glycolipid. Using this unique model, we showed that both iNKT cells and conventional T cells required CCR4 for competitive localization into the bronchoalveolar lavage/airways compartment. These results establish for the first time that the pulmonary localization of iNKT cells critical for the induction of AHR requires CCR4 expression by iNKT cells.  相似文献   
50.
The cytoplasmic N terminus of the Na,K-ATPase is a highly charged and flexible structure that comprises three predicted helical regions including H1 spanning residues 27 to 33 and H2 spanning residues 42 to 50. Previous deletion mutagenesis experiments showed that deletion of residues up to and including most of H2 shifts the E(1)/E(2) conformational equilibrium toward E(1). The present study describes a clustered charge-to-alanine mutagenesis approach designed to delineate specific sites within the N terminus that modulate the steady-state E(1) <--> E(2) and E(1)P <--> E(2)P poise. Criteria to assess shifts in poise include (i) sensitivity to inhibition by inorganic orthovanadate to assess overall poise; (ii) K(+)-sensitivity of Na-ATPase measured at micromolar ATP to assess changes in the E(2)(K) + ATP --> E(1) x ATP + K(+) rate; (iii) K'(ATP) for low-affinity ATP binding at the latter step; (iv) overall catalytic turnover, and (v) the E(1)P --> E(2)P transition. The results of alanine replacements in H1 (31KKE) suggest that this site stabilizes E(2)P and to a lesser extent E(2). In H2, residues within 47HRK have a role in stabilizing E(2) but not E(2)P as revealed with double mutants 31KKE --> AAA/47H --> A and 31KKE --> AAA/47HRK --> AAA. Taken together, these observations suggest that sites 31KKE in H1 and 47HRK in H2 have distinct roles in modulating the enzyme's conformational transitions during the catalytic cycle of the enzyme.  相似文献   
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