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991.
BACKGROUND: Metabolic syndrome and its risk factors are predictors of cardiovascular events. Metabolic syndrome is also directly associated with echocardiographic phenotypes. METHODS: The current study is the first to investigate the factors associated with both metabolic syndrome risk factors and echocardiographic phenotypes and assess their heritability. Multivariate factor analysis was performed on 15 traits in 1393 African-Americans and 1133 whites, as well as stratified by type 2 diabetes mellitus status. RESULTS: Factor analysis with varimax rotation established four to five latent factors across ethnicities and diabetes mellitus stratifications. Among metabolic syndrome risk factors, blood pressure was the most highly correlated with cardiac traits. The factor domains, in the order of the proportion of variance explained, were 'left ventricle wall thickness', 'left ventricle geometry', 'blood pressure', 'BMI-insulin', and 'lipid-insulin'. Factor analysis without any rotation identified special (cross domain) metabolic syndrome-echocardiographic factors, 'blood pressure-left ventricle geometry' and 'blood pressure-left ventricle dimension-wall thickness' in whites. Fifty to 57% of the total original risk factor variance was explained by the latent factors. Heritability was highest for BMI-insulin (37-53%), lowest for 'blood pressure' factors (15-27%), and intermediate for metabolic syndrome-echocardiographic factors. CONCLUSION: These latent factors identified can be utilized as summary phenotypes in epidemiological, linkage, and association studies.  相似文献   
992.
We investigated whether intestinal lipoprotein overproduction in a fructose-fed, insulin-resistant hamster model is prevented with insulin sensitization. Syrian Golden hamsters were fed either chow, 60% fructose for 5 wk, chow for 5 wk with the insulin sensitizer rosiglitazone added for the last 3 wk, or 60% fructose plus rosiglitazone. In vivo Triton studies showed a 2- to 3-fold increase in the large (Svedberg unit > 400) and smaller (Sf 100-400) triglyceride-rich lipoprotein particle apolipoprotein B48 (apoB48) but not triglyceride secretion with fructose feeding in the fasted state (P < 0.01) and partial normalization with rosiglitazone in fructose-fed hamsters. Ex vivo pulse-chase labeling of enterocytes confirmed the oversecretion of apoB48 lipoproteins with fructose feeding. Intestinal lipoprotein oversecretion was associated with increased expression of microsomal triglyceride transfer protein expression. With rosiglitazone treatment of fructose-fed hamsters, there was approximately 50% reduction in apoB48 secretion from primary cultured enterocytes and amelioration of the elevated microsomal triglyceride transfer protein mass and activity in fructose-fed hamsters. In contrast, in the postprandial state, the major differences between nutritional and drug intervention protocols were evident in triglyceride-rich lipoprotein triglyceride and not apoB48 secretion rates. The data suggest that intestinal lipoprotein overproduction can be ameliorated with the insulin sensitizer rosiglitazone.  相似文献   
993.
PURPOSE: Our goal was to compare initial operative and nonoperative management for periappendiceal abscess complicating appendicitis. METHODS: This study is a retrospective review of 155 consecutive patients with appendicitis complicated by periappendiceal abscess treated between 1992 and 1998. Eighty-eight patients were treated initially nonoperatively, and 67 patients were treated operatively. All patients had localized abdominal tenderness and either computed tomography or intraoperative documentation of an abscess. RESULTS: Our patient population consisted of 107 males and 48 females, with an average age of 33 (range, 16–75) years. Age, gender, comorbidity, white blood cell count, temperature, and heart rate did not differ significantly between groups. For the initial nonoperative management group, the failure rate was 5.8 percent and the appendicitis recurrence rate was 8 percent after a mean follow-up of 36 weeks. The response to treatment of the initial nonoperative group and the initial operative group was compared by length of stay (9±5 daysvs. 9±3 days;P=not significant), days until white blood cell count normalized (3.8±4 daysvs. 3.1±3 days;P=not significant), days until temperature normalized (3.2±3 daysvs. 3.1±2 days;P=not significant), and days until a regular diet was tolerated (4.7±4 daysvs. 4.6±3 days;P=not significant). Complication rate was significantly lower in the nonoperative group (17vs. 36 percent;P=0.008). CONCLUSIONS: Initial nonoperative management of appendicitis complicated by periappendiceal abscess is safe and effective. Patients undergoing initial nonoperative management have a lower rate of complications, but they are at risk for recurrent appendicitis.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, June 24 to 29, 2000.  相似文献   
994.
Regression of coronary aneurysms in patients with Kawasaki syndrome   总被引:3,自引:0,他引:3  
Coronary aneurysms were demonstrated echocardiographically in 34 of 186 patients who presented with Kawasaki syndrome between 1979 and 1983. The aneurysms were confirmed by selective coronary angiography in 27 patients and by postmortem examination in one. The 27 surviving patients with proven aneurysms were followed for 2 to 40 months (mean 15), during which they received low dose (5 to 10 mg/kg) aspirin daily. Progressive improvement and resolution of aneurysms were observed by serial echocardiography in 18 patients and confirmed by angiography in 14. Coronary aneurysms persisted, however, in nine other patients for 14 to 40 months (mean 25.7). The incidence of aneurysm resolution was higher in children less than 1 year of age at the onset of the illness than in patients older than 1 year (100% vs 50%; p less than .001). Aneurysms were more likely to resolve in girls than in boys (100% vs 42%; p less than .001). Fusiform aneurysms tended to resolve more frequently than saccular lesions (80% vs 18%; p less than .025). Aneurysms located distally in the coronary arteries appear to regress more rapidly than proximal ones. We conclude that an age of less than 1 year at the onset of Kawasaki syndrome, female sex, and fusiform aneurysm morphology are significant factors that favor resolution of coronary artery aneurysms. However, important questions remain with regard to the long-term fate and functional capabilities of these healed lesions.  相似文献   
995.
The interphotoreceptor matrix (IPM) occupies the extracellular space between the photoreceptors of the retina and the apical surface of the retinal pigmented epithelium. A large proportion of the IPM is composed of aqueous-insoluble glycoconjugates, including chondroitin sulfate-containing proteoglycans, the distribution of which exhibits both apical-basal and photoreceptor cell type-specific heterogeneities. The precise function of most insoluble IPM constituents is unknown, although the available evidence suggests some may contribute to retinal adhesion or photoreceptor survival. We have now identified basic fibroblast growth factor (bFGF), or an immunologically related protein from the FGF family, within the IPM. The IPM is labeled on sections of primate retinas by a battery of polyclonal antibodies (Abs) directed against various peptide sequences of bFGF and by an Ab to bovine brain bFGF. bFGF Abs also bind to purified preparations of aqueous-insoluble IPM. All bFGF Abs utilized cross-react with equivalent low molecular mass components of 16.5-17.5 kDa on Western blots of insoluble IPM proteins, purified bFGF, and recombinant bFGF. The Abs do not bind any aqueous-soluble IPM components, suggesting that the bFGF is normally bound to an insoluble IPM constituent(s) in situ. The fact that bFGF is sequestered in the IPM and is located in such close proximity to the photoreceptors, the retinal pigmented epithelium, and Mueller's glia raises the strong possibility that it is synthesized by and regulates the activities of one or more of these three cell types in vivo.  相似文献   
996.
Eight asymptomatic patients (mean age 19 years, range 7 to 32) with congenitally corrected transposition of the great arteries (CCTGA) underwent equilibrium gated radionuclide angiocardiography at rest and during supine bicycle exercise to assess systemic (morphologic right) and pulmonary (morphologic left) ventricular function. Five patients had normal intracardiac hemodynamic values, 2 had trivial atrioventricular valve regurgitation and 1 patient had trivial pulmonary ventricular outflow tract obstruction. Average exercise duration was 11 +/- 1 minute, with limitation due only to fatigue. At peak exercise, heart rate increased 225% and systolic blood pressure 152% over the rest value. Pulmonary ventricular ejection fraction at rest was 51 +/- 3% (mean +/- standard error of the mean); it did not change significantly at peak stress, 53 +/- 2%. Systemic ventricular ejection fraction was 48 +/- 4% at rest and increased to 64 +/- 4% at peak exercise (p less than 0.01). Count-based volume changes for the pulmonary chamber showed no significant change in end-diastolic or systolic counts at peak exercise (109 +/- 8% and 106 +/- 9% of rest value, respectively). However, end-diastolic counts decreased 13% (87 +/- 3% of rest value) and end-systolic counts 34% (62 +/- 7% of rest value) at peak exercise in the systemic ventricle. These data suggest normal systemic and impaired pulmonary ventricular function in patients with congenitally corrected transposition of the great arteries unaccompanied by significant associated lesions. These findings have important clinical implications in the setting of complex congenital heart disease in patients in whom a morphologic right ventricle functions as the systemic pumping chamber. Despite the pulmonary ventricular dysfunction, symptoms were not apparent at rest or during exercise.  相似文献   
997.
We report here on a preliminary human autologous transplantation study of retroviral gene transfer to bone marrow (BM) and peripheral blood (PB)-derived CD34-enriched cells. Eleven patients with multiple myeloma or breast cancer had cyclophosphamide and filgrastim-mobilized PB cells CD34-enriched and transduced with a retroviral marking vector containing the neomycin resistance gene, and CD34-enriched BM cells transduced with a second marking vector also containing a neomycin resistance gene. After high-dose conditioning therapy, both transduced cell populations were reinfused and patients were followed over time for the presence of the marker gene and any adverse effects related to the gene-transfer procedure. All 10 evaluable patients had the marker gene detected at the time of engraftment, and 3 of 9 patients had persistence of the marker gene for greater than 18 months posttransplantation. The marker gene was detected in multiple lineages, including granulocytes, T cells, and B cells. The source of the marking was both the transduced PB graft and the BM graft, with a suggestion of better long-term marking originating from the PB graft. The steady- state levels of marking were low, with only 1:1000 to 1:10,000 cells positive. There was no toxicity noted, and patients did not develop detectable replication-competent helper virus at any time posttransplantation. These results suggest that mobilized PB cells may be preferable to BM for gene therapy applications and that progeny of mobilized peripheral blood cells can contribute long-term to engraftment of multiple lineages.  相似文献   
998.
Emr, an Escherichia coli locus for multidrug resistance.   总被引:31,自引:5,他引:31       下载免费PDF全文
An Escherichia coli chromosomal DNA fragment cloned on a multicopy plasmid conferred resistance to carbonylcyanide m-chlorophenylhydrazone, nalidixic acid, and a number of other toxic compounds. The sequence of the cloned emr locus located at minute 57.5 of the chromosome revealed two open reading frames, emrA and emrB. emrB encodes a highly hydrophobic 56.2-kDa peptide, with 14 potential alpha-helices to span the inner membrane. The peptide is homologous to QacA, a multidrug-resistant pump from Staphylococcus aureus, and belongs to a gene family that includes tetracycline-resistant pumps of Gram-positive bacteria and the galactose/H+ symporter of E. coli. emrA encodes a putative 42.7-kDa peptide containing a single hydrophobic domain and a large C-terminal hydrophilic domain. An active pho-fusion to the C domain suggested that EmrA is a membrane protein. Disruption of emrB significantly increased sensitivity of cells to uncouplers. The cellular content of uncoupler increased in the order: overexpressed emrB cells greater than wild type greater than emrB-.  相似文献   
999.
OBJECTIVE: Azathioprine and 6-mercaptopurine interact in purine metabolism and DNA synthesis, thus their potential mutagenic effects have been of concern in the management of inflammatory bowel disease (IBD), especially in patients of childbearing age. Although several clinical studies have indicated their safety in both reproduction and pregnancy, in a recent large epidemiological study concerns were raised about their adverse effects in pregnant patients with IBD, and experimental or basic data on this subject are limited. The aim of this study was to investigate sperm production, sperm quality, and reproductive outcome following prolonged 6-MP administration to male mice. MATERIAL AND METHODS: Highly inbred Balb/c adult male mice were used. 6-MP at doses of 2, 5, and 8 mg/kg (n = 9 for each group) was given daily for 51 days and the treatment group was compared with controls. After 45 days of treatment, the mice were mated with females. Following 13 days of pregnancy, the products of conception were evaluated and live fetuses were examined for gross malformations. Sperm production and morphology were examined after 51 days of 6-MP administration. RESULTS: Treatment with 6-MP at all doses did not affect sperm morphology and sperm production in the testicular tubules, as compared with controls (70% normal sperm). However, pregnancy rates were inversely related to escalating doses of 6-MP: 55%, 41%, 28%, and 16% for control, 2, 5, and 8 mg/kg groups, respectively. Resorption rates (abortions) were 21% in the control group as compared with 45-50% in all the treatment groups, but the incidence of major congenital malformations was not increased. CONCLUSIONS: Long-term 6-MP treatment in male mice did not impair sperm production and sperm morphology. However, a significantly high rate of embryonic resorption indicated occult sperm damage. Thus, normal sperm analysis does not necessarily imply that sperm damage at genetic level did not occur. It is difficult to extrapolate from these results to the clinical use of 6-MP/azathioprine in IBD patients; however, further basic genetic testing for DNA damage and clinical follow-up are warranted.  相似文献   
1000.
Objectives: To investigate two questions in a community based population of people with chronic shoulder pain. Firstly, does chronic pain lead to impaired psychological health over time? Secondly, how does restriction of daily activity influence pain perception and psychological health? Methods: Two postal surveys, two years apart, were carried out to identify a group of subjects with chronic shoulder pain. The first survey was sent to a random sample of adults (n=40026) registered with a primary care practice, and included a pain manikin, demographic information, and the Hospital Anxiety and Depression scale (HAD). The second survey was sent to those subjects who reported unilateral shoulder region pain in the first survey and it included a shoulder-specific disability scale, pain severity score, and the HAD. Results: 2606 (65.1%) people responded to the initial survey. Of these, 304 (11.7%) reported unilateral shoulder region pain at baseline. In the subsequent survey, there were 234 responders (83.3% adjusted response): 142 of these reported shoulder pain and formed our study group of "subjects with chronic shoulder pain". Within this group there was no significant change in psychological distress scores between baseline and follow up. Both the disability score and psychological distress scores correlated significantly with pain severity (disability v pain r=0.536, p<0.001; psychological distress v pain r=0.269, p=0.002). When the correlation between disability and pain severity was corrected for possible confounders, it remained significant (r=0.490, p<0.001). This was not the case for the correlation between psychological distress and pain (p>0.05). Disability was significantly correlated with psychological distress on univariate (r=0.445, p<0.001) and multivariate analysis (r=0.341, p=0.002). Conclusion: In those with chronic shoulder pain the relation between pain and psychological health seems to be linked to disability. Psychological distress was not explained by persistent pain itself.  相似文献   
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