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OBJECTIVES: We hypothesized that the plasma atrial natriuretic peptide (ANP) level reflects atrial degenerative change and may predict the outcome of the maze procedure. BACKGROUND: Although a larger preoperative left atrial dimension and longer duration of atrial fibrillation (AF) have been reported in patients with persistent AF than in those with sinus rhythm (SR), these individual factors were not enough to predict the outcome of the maze procedure. METHODS: Preoperative plasma ANP levels were measured in consecutive 62 patients who underwent the Kosakai's modified maze procedure. Moreover, we performed histological and molecular biological examinations in the resected left atrial tissues. RESULTS: The preoperative plasma ANP was lower in the AF group (n = 13) than it was in the SR group (n = 49) (p < 0.001). Multiple logistic regression analysis revealed that duration of AF and plasma ANP were independently associated with postoperative cardiac rhythm. Among 41 patients with a higher plasma ANP or shorter duration of AF than the median value, SR was restored in 95% of patients. In contrast, in 21 patients with a lower plasma ANP and a longer duration of AF than the median value, SR was restored only in 48% of patients. Histological examination revealed that the collagen volume in the left atrial tissue was higher in AF than it was in SR and inversely correlated with plasma ANP. In addition, the messenger RNA expressions of ANP, collagen type I and type III were lower in AF than they were in SR. CONCLUSIONS: These results suggest that a combination of plasma ANP and/or duration of AF may predict the success rate for the maze operation. Advanced atrial degenerative change may result in a decrease of atrial ANP secretion.  相似文献   
23.
Beta-1-adrenergic receptor (beta1-AR) blockers reduce both the incidence of sudden death and the ventricular volume in heart failure. In vitro, the Gly389 variant of beta1-AR mediates less adenylyl cyclase activities than the Arg389 variant, so Arg389Gly polymorphism was investigated with regard to the genesis, progression, or arrhythmogenesis of dilated cardiomyopathy (DCM). Allele and genotype frequencies of the Arg389Gly polymorphism were determined in 163 DCM patients and 157 age- and sex-matched controls. There were no differences in genotype and allele frequencies between patients and controls. Echocardiograms, left ventriculograms and 24h-Holter electrocardiograms were evaluated in the DCM patients and none of the clinical indices, other than ventricular tachycardia (VT), differed among the 3 genotypes. The Gly389 allele was more frequent in the VT(-) group than in the VT(+) group (0.46 vs 0.24, p=0.001). In univariate analysis, the odds ratio for VT in patients carrying 1 or 2 copies of the Gly389 allele was 0.29 ([95% confidence interval, 0.13-0.64], p=0.002), when compared with the Arg389 homozygotes. The Gly389 variant supressed the occurrence of VT in DCM, suggesting that this allele confers a decreased risk of sudden death.  相似文献   
24.
BACKGROUND/AIMS: Anastomotic leak at the pancreatojejunostomy remains a common and dreaded complication after pancreaticoduodenectomy. Our aim was to determine the incidence, presentation, methods of management, and preoperative and postoperative factors that influence the clinical outcome. METHODOLOGY: We reviewed our collective experience with 70 consecutive patients from 1985 to 2000 for a variety of pathologic indications. Clinical, biochemical, intraoperative and postoperative factors were reviewed in an attempt to determine prognostic factors. RESULTS: Nine patients (12%) developed a pancreatic anastomotic leak as determined by increased amylase in drainage fluid (70%), were clinically insignificant and were managed by simple maintenance of intraoperatively placed drains. Although octreotide was used therapeutically in 4 patients (44%), significant, objective response was noted in all patients. Of the clinical, biochemical, intraoperative and postoperative factors reviewed to determine prognostic factors, a large amount of postoperative pancreatic juice output (P = 0.02) was a significant risk factor for pancreatic fistula formation. CONCLUSIONS: We conclude that most anastomotic leak at pancreaticoenterostomy after pancreaticoduodenectomy can be managed conservatively. Use of octreotide to aid in closure of the pancreatic leak was satisfactory.  相似文献   
25.
We report a case of secondary pouchitis, defined as a mucosal inflammatory lesion in the ileal reservoir provoked by pouch-related complication following total colectomy and pouch anal anastomosis, which was successfully treated by salvage surgery- A 20-year-old woman with ulcerative colitis developed acute severe bloody diarrhea following proctocolectomy, ileal pouch-anal anastomosis and diverting ileostomy. She was diagnosed as having a secondary pouchitis mainly caused by a peripouch abscess and partly concerned with the abnormal pouch formation. The remnant rectum and ileal pouch were excised and ileal pouch-anal anastomosis and diverting ileostomy were constructed. The postoperative course was uneventful with no sign of pouchitis. Salvage surgery may be indicated to treat secondary pouchitis when caused by surgery-related complications.  相似文献   
26.
We evaluated the usefulness of contrast-enhanced ultrasonography(US) for detecting and differentiating gallbladder lesions. Contrast-enhanced coded phase-inversion harmonic US was performed on 90 patients with gallbladder abnormalities. After administering Levovist, we observed the gallbladders in real time. Contrast-enhanced coded phase-inversion harmonic ultrasonography was compared with B-mode US and contrast-enhanced computer tomography (CT) with regard to the sensitivity and specificity in depicting the elevated gallbladder lesions. Furthermore, we assessed how the vascular patterns of the elevated gallbladder lesions depicted by contrast-enhanced US correlated with the diagnosis. Contrast-enhanced US efficiently discriminated true lesions from biliary sludge, unlike B-mode US. Consequently, contrast-enhanced US was more specific (100%) than B-mode US (81%), although their sensitivities were similar (98% and 96%, respectively). Contrast-enhanced US was also more sensitive that contrast-enhanced CT (98% versus 79%), although the two methods were equally sensitive (100% versus 95%). We classified the vascular patterns of the abnormalities depicted by contrast-enhanced US in the 90 cases into types 1 to 4, which represent branch-like, heterogeneous, homogeneous, and avascular patterns, respectively. All type 1 and 2 lesions were over 10 mm in size while most (88%) type 3 lesions were 10 mm or less in size. While the majority of carcinomas (86%) were type 1 or 2, three benign lesions also showed these patterns. Thus, the vascular pattern may simply reflect the size of the lesion and therefore its usefulness in diagnosing gallbladder lesions may be limited. Nevertheless, contrast-enhanced US is clearly superior to the other techniques in discriminating biliary sludge from other lesions.  相似文献   
27.
BACKGROUND: Elderly people frequently have symptoms of fullness and appetite loss due to impaired gastric motor activity. These symptoms may cause malnutrition, immunosuppression and other complications. OBJECTIVE: The effects of aging and daily activity on gastric motility in the elderly were investigated by electrogastrography and the (13)C-acetate breath test. METHODS: We enrolled seven active elderly subjects (active elderly group), seven elderly subjects staying at a geriatric facility who had reduced mental and physical capacities (inactive elderly group) and seven healthy young volunteers (young group). Electrogastrography was recorded before and after ingestion of a (13)C-acetate-mixed liquid meal. Expired air was sampled every 10 min after the meal to measure the (13)CO(2) concentration. RESULTS: The ratio of the incidence of the 3-cpm wave (gastric intrinsic frequency) during the postprandial period compared to the fasting state was reduced in both elderly groups compared to young subjects, and the reduction was greater in the inactive elderly than in the active elderly group. The ratio of the amplitude of the peak frequency during the postprandial period to that in the fasting state (power ratio) was also lower in the elderly groups. The time of peak (13)CO(2) expiration was delayed in the active elderly and more so in the inactive elderly group. CONCLUSIONS: Postprandial peristalsis and gastric contractile force are reduced in the elderly, and gastric emptying is delayed indicating a reduction in gastric motor activity.  相似文献   
28.
BACKGROUND: Increased arterial stiffness has been shown to be associated with coronary heart disease (CHD). However, it remains unclear as to whether the second derivative of the finger photoplethysmogram (SDPTG), a non-invasive method for the assessment of arterial stiffness, is useful for the estimation of risk of CHD in the general population. METHODS AND RESULTS: The SDPTG in 211 subjects (age: 63+/-15 years, range: 21-91 years, 93 males) was recorded without apparent atherosclerotic disorders from a community. The relationship between the SDPTG indices (b/a and d/a) and coronary risk factors (n=211) or the Framingham risk score (n=158, age: 60+/-12 years, range: 30-74 years, 63 males) were analyzed. The SDPTG indices significantly correlated with the Framingham risk score in both genders (b/a; r(male) =0.43, r(female) =0.54 and d/a; r(male) =-0.38, r(female) =-0.58), as well as several coronary risk factors. In the receiver operating characteristics curve analyses, the b/a discriminated high-risk subjects for CHD, who were in the highest quintile of the Framingham risk score in each gender, with a sensitivity and specificity of 0.85 and 0.58 in males and 0.83 and 0.72 in females, respectively. CONCLUSIONS: These results suggest that the SDPTG is useful for the estimation of risk of CHD in the general population.  相似文献   
29.
Elevated production of anti-DNA antibody in patients with systemic lupus erythematosus (SLE) is a central problem in the pathogenesis of tissue injury. In the present study, we attempted to manipulate anti-DNA antibody production through the antigen-cytotoxic drug conjugates, DNA-daunorubicin complexes. The effect of DNA-daunorubicin complexes was determined by examining SLE lymphocytes for spontaneous in vitro production of anti-DNA antibody. These complexes, at 2 μg/ml, suppressed anti-DNA antibody production, but not total IgG production, which suggests that specific suppression of anti-DNA antibody production was achieved at this concentration. We believe that the DNA-daunorubicin complexes affected mainly B cells, since such suppression was obtained by treating B cells, as well as B plus T cells. Furthermore, the complexes had no effect on the proliferative responses of SLE T cells to DNA, phytohemagglutinin, or concanavalin A. These results indicate that DNA-daunorubicin complexes may have the potential for selectively suppressing anti-DNA antibody production in patients with SLE.  相似文献   
30.
Calcitonin receptor-like receptor/receptor activity-modifying protein 2 (CRLR/RAMP2) and CRLR/RAMP3 complexes have been reported to be specific adrenomedullin (AM) receptors. In the present study, we evaluated the pathophysiological significance of renal AM and its receptor system in aortocaval shunt (ACS) rats. Renal AM levels were measured serially during 5 weeks after the operation. Renal gene expressions of AM, CRLR, RAMP2, and RAMP3 were measured at 2 weeks (decompensated phase) and 5 weeks (compensated phase) after the operation. Immunohistochemical localizations of renal AM were also evaluated. Furthermore, the relations between urinary sodium excretion (UNaV) and renal AM levels were evaluated. Renal AM levels were higher in ACS than in control animals only at 1, 2, and 3 weeks after the operation. At 2 weeks after the operation, renal AM mRNA expression was also higher in ACS than in control animals. CRLR, RAMP2, and RAMP3 mRNAs were expressed in the kidney, but there were no differences between the 2 groups. Immunohistochemistry revealed the positive AM immunostaining within the renal tubular cells, and it was more intense in ACS than in control animals. There were significant correlations between UNaV and renal AM levels. At 5 weeks after the operation, there were no differences in mRNA levels of AM, CRLR, RAMP2, and RAMP3 between the 2 groups. There was a significant correlation between UNaV and medullary AM levels. The present findings suggest that increased renal AM levels in decompensated heart failure, presumably due to increased AM production in renal tubules, in part, are involved in the regulation of sodium excretion.  相似文献   
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