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21.
The detection of chromosomal abnormalities in patients with mental retardation (MR) and dysmorphic features increases with improvements of molecular cytogenetic methods. We report on six patients referred for detailed characterization of chromosomal abnormalities (four translocations, one inversion, one deletion) detected by conventional cytogenetics, in whom metaphase CGH revealed imbalances not involved in the initially detected rearrangements. The detected abnormalities were validated by real-time PCR. Parents were investigated by CGH in four cases. The genomic screening revealed interstitial deletions of 2q33.2-q34, 3p21, 4q12-q13.1, 6q25, 13q22.2-q31.1, and 14q12. The estimated minimum sizes of the deletions ranged from 2.65 to 9.27 Mb. The CGH assay did not reveal imbalances that colocalized with the breakpoints of the inversion or the translocations. The deletion of 6q included ESR1, in which polymorphisms are associated with variation of adult height. FOXG1B, known to be involved in cortical development, was located in the 14q deletion. The results illustrate that whole-genome molecular cytogenetic analysis of phenotypically affected patients with abnormal conventional karyotypes may detect inapparent molecular cytogenetic abnormalities in patients with microscopic chromosomal abnormalities and that these data provide additional information of clinical importance.  相似文献   
22.

Background  

Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) are expressed by microglia and infiltrating macrophages following ischemic stroke. Whereas IL-1β is primarily neurotoxic in ischemic stroke, TNF-α may have neurotoxic and/or neuroprotective effects. We investigated whether IL-1β and TNF-α are synthesized by overlapping or segregated populations of cells after ischemic stroke in mice.  相似文献   
23.
OBJECTIVE: The voltage-gated KCNQ1 potassium channel regulates key physiological functions in a number of tissues. In the heart, KCNQ1 alpha-subunits assemble with KCNE1 beta-subunits forming a channel complex constituting the delayed rectifier current I(Ks). In epithelia, KCNQ1 channels participate in controlling body electrolyte homeostasis. Several regulatory mechanisms of the KCNQ1 channel complexes have been reported, including protein kinase A (PKA)-phosphorylation and beta-subunit interactions. However, the mechanisms controlling the membrane density of KCNQ1 channels have attracted less attention. METHODS AND RESULTS: Here we demonstrate that KCNQ1 proteins expressed in HEK293 cells are down-regulated by Nedd4/Nedd4-like ubiquitin-protein ligases. KCNQ1 and KCNQ1/KCNE1 currents were reduced upon co-expression of Nedd4-2, the isoform among the nine members of the Nedd4/Nedd4-like family displaying the highest expression level in human heart. In vivo expression of a catalytically inactive form of Nedd4-2, able to antagonize endogenous Nedd4-2 in guinea-pig cardiomyocytes, increased I(Ks) significantly, but did not modify I(K1). Concomitant with the reduction in current induced by Nedd4-2, an increased ubiquitylation as well as a decreased total level of KCNQ1 proteins were observed in HEK293 cells. Pull-down and co-immunoprecipitation experiments showed that Nedd4-2 interacts with the C-terminal part of KCNQ1. The Nedd4/Nedd4-like-mediated regulation of the KCNQ1 channel complexes is strictly dependent on a PY motif located in the distal part of the C-terminal domain. When this motif was mutated, the current and ubiquitylation levels were unaffected by Nedd4-2, and Nedd4-2 proteins were neither pulled-down nor co-immunoprecipitated. CONCLUSIONS: These results suggest that KCNQ1 internalization and stability is physiologically regulated by its Nedd4/Nedd4-like-dependent ubiquitylation. This mechanism may thereby be important in regulating the surface density of the KCNQ1 channels in cardiomyocytes and other cell types.  相似文献   
24.
Muscle-derived interleukin-6: possible biological effects   总被引:14,自引:5,他引:14  
Interleukin-6 (IL-6) is produced locally in working skeletal muscle and can account for the increase in plasma IL-6 during exercise. The production of IL-6 during exercise is related to the intensity and duration of the exercise, and low muscle glycogen content stimulates the production. Muscle-derived IL-6 is released into the circulation during exercise in high amounts and is likely to work in a hormone-like fashion, exerting an effect on the liver and adipose tissue, thereby contributing to the maintenance of glucose homeostasis during exercise and mediating exercise-induced lipolysis. Muscle-derived IL-6 may also work to inhibit the effects of pro-inflammatory cytokines such as tumour necrosis factor α. The latter cytokine is produced by adipose tissue and inflammatory cells and appears to play a pathogenetic role in insulin resistance and atherogenesis.  相似文献   
25.
Old people of non-western minority backgrounds are an invisible group in Norway in several ways: in the national debate about the ageing population, in geriatric health care services, and in the general picture of ethnic minorities. There is a lack of knowledge about health and care amongst old migrants. This study aimed at exploring nurse managers' perceptions of the content of community health nursing care of older people from non-western countries of origin, and the challenges associated with caring for this group of patients. The study took place in a medium-sized Norwegian community, a mostly urban area with surrounding rural areas. The community health nursing system was organized in six districts with nurses in management positions, covering nursing homes, special housing and home-based care. Data were collected by a questionnaire with structured and open-ended questions answered by 18 nurse managers. The data provided scarce information, but indicated a lack of systematic cultural care assessments. Community health nursing of old non-western migrant patients was described as deficient and a demanding burden. The challenges were captured in four themes: language barriers, family involvement in care, deficiencies in cultural competency and the need for development. Increased competency, action and local responsibility were identified as propositions to manage the challenges. The lack of awareness and knowledge concerning cultural issues found in this study highlights the need for further development and research on this topic.  相似文献   
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Objectives

To analyse the effects of rosiglitazone administered at different times on neointimal formation in hypercholesterolemic rabbits following vascular injury.

Methods

Thirty-nine rabbits on a hypercholesterolemic diet were included. The animals underwent balloon catheter injury to the right iliac artery on day 14. They were divided into three groups as follows: control group, 13 rabbits without rosiglitazone; group I, 13 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) for 28 days after the vascular injury; and group II, 13 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) during all the experiment (42 days). Histological analysis was done by an experienced pathologist who was unaware of the rosiglitazone treatment. Histomorphometric parameters were performed by calculation of the luminal and intimal layer area, and intima/media layer area ratio (the area of the intimal layer divided by the area of the medial layer).

Results

Intimal area was significantly lower in group II vs. CG (p = 0.024) and group I (p = 0.006). Luminal layer area was higher in group II vs. CG (p < 0.0001) and group I (p < 0.0001). Intima/media layer area ratio was equal between CG and group I. Intima/media layer ratio area was significantly lower in group II vs. control group (p < 0.021) and group I (p < 0.003). There was a significant reduction of 65% and 71% in intima/media layer area ratio in group II vs. control group and group I, respectively.

Conclusion

Pretreatment with rosiglitazone in hypercholesterolemic rabbits submitted to vascular injury significantly reduces neointimal formation.  相似文献   
29.
Clinical Rheumatology - Individualisation of rheumatoid arthritis (RA) treatment needs to take account of individual patients’ preferences to increase patient-centeredness in treatment...  相似文献   
30.
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