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91.
92.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
93.
Dusel JA Burdon KP Hicks PJ Hawkins GA Bowden DW Freedman BI 《Kidney international》2005,68(1):256-262
BACKGROUND: Podocin, encoded by NPHS2 and mapped to 1q25.2, is an integral membrane protein exclusively expressed in glomerular podocytes. Mutations in the NPHS2 gene cause autosomal-recessive nephrotic syndrome and have been associated with proteinuria in several populations. Evidence for linkage of end-stage renal disease (ESRD) to chromosome 1q25-31 in the region of NPHS2 has been identified in a genome-wide scan in African American (AA) siblings. METHODS: To investigate the potential role of this gene in ESRD, we sequenced all coding regions and approximately 2 kb of upstream promoter sequence of NPHS2 in 96 unrelated AA nondiabetic ESRD cases and 96 healthy population-based AA controls, and assessed several single nucleotide polymorphisms (SNPs) for association in a larger case-control sample. RESULTS: Fifty-five variants were identified with minor allele frequencies ranging from <1% to 44%. Twenty-three polymorphisms were located in the promoter region, 11 were exonic, 13 were intronic, and 8 were in the 5' and 3'- untranslated regions. Two novel nonsynonymous coding SNPs were identified (A44E and A61V). An insertion polymorphism in intron 3, IVS3+9insA, was detected in 6 ESRD patients and in no controls. This variant, and 4 other common SNPs, were evaluated in a larger sample of 288 AA ESRD cases and 278 AA controls. The overall minor allele frequencies for the insertion allele were 0.018 in cases and 0.002 in controls. Significant evidence of association of IVS3+9insA was observed (P= 0.012), and the haplotype containing the insertion allele in cases was also associated. CONCLUSION: These results suggest that uncommon variants of the NPHS2 gene may play a role in the development of nondiabetic ESRD in AAs. 相似文献
94.
Sutton BS Langefeld CD Williams AH Norris JM Saad MF Haffner SM Bowden DW 《Obesity research》2005,13(9):1491-1498
Proopiomelanocortin (POMC) has been found to be associated with rare Mendelian forms of obesity in children, and, in linkage studies, genomic regions containing the POMC locus have been linked to leptin levels, a predictor of obesity, in white, Mexican-American, and African-American families. POMC polymorphisms have not been investigated in detail for association with obesity in the general population. Five single nucleotide polymorphisms (SNPs) (G-3460C, C17T, G3473A, C3755T, and A7069G) were genotyped on 811 Hispanic individuals in the Insulin Resistance Atherosclerosis Family Study and tested for association with multiple obesity quantitative traits. General and family-based association analyses for each individual SNP and for haplotypes were performed using the generalized estimating equation and quantitative pedigree disequilibrium test (QPDT), respectively. Modest but consistent associations were observed for SNP C3755T, with p values ranging from 0.011 to 0.045 for association with BMI, waist, visceral adipose tissue, and subcutaneous adipose tissue. G-3460C, G3473A, and A7069G were also found to be associated with additional obesity measurements (p value 0.025 to 0.04), with comparable levels of evidence observed for linkage disequilibrium between these traits and these SNPs. Results of the haplotype analyses were also consistent with the single SNP analysis, with haplotypes containing C3755T showing the greatest evidence of association (p values ranging 0.004 to 0.048). Monte Carlo simulations (gene dropping) that account for the number of comparisons and the correlation structure indicate that the multivariate significance for these obesity traits with these polymorphisms was p = 0.0091. Collectively, the POMC polymorphisms showed consistent evidence for association with obesity traits in Hispanic Americans across several analytical approaches using SNP and haplotype analysis. These results support the hypothesis that POMC contributes genetically to the development of obesity. 相似文献
95.
Hsu FC Lenchik L Nicklas BJ Lohman K Register TC Mychaleckyj J Langefeld CD Freedman BI Bowden DW Carr JJ 《Obesity research》2005,13(2):312-319
OBJECTIVE: The purpose of this study was to investigate the heritability of body composition measured by DXA in the Diabetes Heart Study (DHS). RESEARCH METHODS AND PROCEDURES: Participants were 292 women and 262 men (age, 38 to 86 years; BMI, 17 to 57 kg/m(2)) from 244 families. There were 492 white and 49 African-American sibling pairs. DXA measurements of percentage fat mass (FM), whole body FM, and lean mass (LM), as well as regional measurements of trunk fat mass (TFM) and appendicular lean mass (ALM), were obtained. Heritability of FM, LM, and BMI were estimated using Sequential Oligogenic Linkage Analysis Routines. RESULTS: After adjusting for age, gender, ethnicity, and height, the heritability estimates of various compositional attributes were %FM = 0.64, whole body FM = 0.71, TFM = 0.63, whole body LM = 0.60, ALM = 0.66, and BMI = 0.64 (all p < 0.0001). Additional adjustment for diabetes status, smoking, dietary intake, and physical activity resulted in only minor changes in the heritability estimates (h(2) = 0.63 to 0.72, all p < 0.0001). Furthermore, heritability of TFM after additional adjustment for whole body FM was significant (h(2) = 0.55, p < 0.0001), and heritability of ALM after additional adjustment for whole body LM was also significant (h(2) = 0.51, p < 0.0001). DISCUSSION: These data suggest that FM and LM measured by DXA are highly heritable and can be effectively used in designing linkage studies to locate genes governing body composition. In addition, regional distribution of FM and LM may be genetically determined. 相似文献
96.
97.
The antitumor antibiotic mitomycin C (MMC) was studied in vitro using L1210 leukemia and 8226 human myeloma cells. Cytotoxicity was evaluated by colony formation in soft agar, and DNA damage was analyzed using alkaline elution filter assays. The purposes of these studies were: (a) to characterize the time course of MMC-DNA damage; (b) to characterize the type of DNA damage [DNA-DNA interstrand cross-links (ISC), DNA-protein cross-links (DPC), single and double strand breaks (SSBs, DSBs)]; and (c) to correlate this damage with cytotoxicity in vitro. Colony-forming assays showed the D0 value for 1 h MMC to be 15.0 microM for L1210 cells and 17 microM for 8226 cells. Alkaline elution studies showed that dose-dependent ISCs and DPCs formed rapidly following MMC exposure. Removal of cross-links was delayed, with only 50% repaired 32 h after exposure. There was a good correlation between ISCs and cytotoxicity in dose-response studies in each cell line. ISCs appeared to comprise most of the MMC-DNA lesions in both cell lines. No DNA SSBs or DSBs were observed following MMC exposure. Nuclei isolated from both cell lines and exposed to MMC produced less MMC alkylation than whole cells but, again, no strand breaks were evident. These results demonstrate that MMC is principally an alkylating agent when used at pharmacological (cytotoxic) concentrations in vitro. The lack of evidence for DNA strand breaks discounts a significant role for putative quinone-generated oxygen free radicals in the production of MMC cytotoxicity. 相似文献
98.
99.
Effects of high-peak pulsed electromagnetic field on the degeneration and regeneration of the common peroneal nerve in rats 总被引:7,自引:0,他引:7
Apart from preliminary notices of present work, previous reports of experimental and clinical trials of the effects of a high-peak pulsed electromagnetic field (PEMF) on degeneration and regeneration of peripheral nerves lacked statistical analysis. Therefore, we designed experiments with standardised operative, histological, cytological and morphometric techniques to assess the effect of PEMF on lesions of the common peroneal nerves in paired male rats matched for age, environmental conditions and level and type of lesion. One of two types of lesion was induced in the left common peroneal nerve: in 12 pairs of rats the nerve was crushed just above the knee and in the remaining 12 pairs the nerve was cut and immediately sutured at the same level. The right common peroneal nerve of each rat served as a control. Animals received 15 minutes of PEMF produced by a Diapulse machine or sham treatment daily for periods ranging from three and a half days to eight weeks after injury. Healthy nerves were unaffected, but after damage there were statistically significant differences between PEMF treated and sham treated rats. PEMF accelerated the recovery of injured limbs and the degeneration, regeneration and maturation of myelinated axons; epineural, perineural and intraneural fibrosis was reduced; and the luminal cross-sectional area of intraneural vessels increased after both types of lesion. Findings are discussed and the need for clinical trials is stressed. 相似文献
100.
Effects of carbamazepine on plasma haloperidol levels 总被引:3,自引:0,他引:3
M W Jann L Ereshefsky S R Saklad D R Seidel C M Davis N R Burch C L Bowden 《Journal of clinical psychopharmacology》1985,5(2):106-109
Plasma haloperidol levels were monitored in three schizophrenic patients when carbamazepine was either added or discontinued. The percent decrease in plasma haloperidol levels due to concomitant carbamazepine therapy was between 59% and 61%. The effects of carbamazepine on plasma haloperidol levels were noted to occur in 2 to 3 weeks. Although no adverse effects occurred in the patients during therapy, careful monitoring of clinical symptoms and plasma haloperidol levels is recommended. 相似文献