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121.
BACKGROUND: Secondary hyperparathyroidism and its effects on bone and viscera are among the most important complications of end-stage renal disease. Despite its ubiquity, little is known about the treated natural history of the disorder. METHODS: We assembled a cohort of 310 patients with endstage renal disease on hemodialysis who were participants in one of four clinical trials of the phosphate binder sevelamer. Baseline parathyroid hormone levels were collected, and the relation between dialysis vintage and other clinical variables with parathyroid hormone were described. RESULTS: There was a direct relation between dialysis vintage and the severity of hyperparathyroidism. Other variables that were significantly associated with PTH on univariate analysis included age, African American race, Kt/V, and the serum concentrations of calcium, phosphate, and bicarbonate. Multivariable linear regression analysis yielded three significant predictors of PTH: calcium, phosphorus, and vintage (5.8% (4.0-7.5%) expected increase in PTH per year of vintage). The model R2 was 0.22. CONCLUSION: Dialysis vintage is a key determinant of the severity of secondary hyperparathyroidism. Vintage and certain laboratory variables should be considered in the evaluation of therapies aimed at modifying the treated natural history of this disorder. 相似文献
122.
123.
Partial venous thrombosis of the pancreatic allografts after simultaneous pancreas-kidney transplantation 总被引:1,自引:0,他引:1
Despite new advances in transplantation, complete venous thrombosis (VT) of the pancreas after simultaneous pancreas kidney (SPK) transplantation usually results in graft loss. Data are limited regarding the outcome and treatment of partial VT of the pancreas allograft. From July 1994 to December 1999, 126 patients with IDDM/end-stage renal disease underwent SPK with systemic bladder drainage at the University of Miami. We retrospectively reviewed our experience regarding the outcome and treatment options of partial VT of the pancreas allografts. From July 1994 to April 1997, partial VT was not seen in the first 66 SPK patients induced with anti-CD3 rnAb and oral or intravenous (i.v.) tacrolimus (TAC) in the operating room. From May 1997 to June 1999, 14 (29%) out of 48 patients had VT. These cases were identified following the i.v. use of TAC with anti-IL-2R antibody-induction therapy (7/15) or without (7/33). Partial thrombosis of the splenic vein (PTSV) was documented in 10 patients, 2 had complete thrombosis of the splenic vein (CTSV), 1 had partial thrombosis of the superior mesenteric vein (PTSMV), and 1 patient had PTSV and PTSMV. These were identified incidentally during routine color Doppler ultrasonography (CDU). None of these SPK recipients demonstrates a change in clinical parameters. The first 8 patients were systemically heparinized, followed by oral anticoagulation, except 1 patient with CTSV. He progressed to complete thrombosis of the pancreas allograft and was treated with percutaneous thrombectomy and urokinase infusion, followed by heparinization and oral anticoagulation. One patient required exploration for bleeding. In an attempt to reduce the morbidity of heparinization, we treated the next 6 patients with PTSV with aspirin followed by serial CDU. All 14 patients had preservation of the endocrine and exocrine pancreatic functions. CDU showed resolution with recanalization of the thrombosed vein(s). From July 1999 to December 1999, 12 SPK recipients were administered TAC orally with or without induction therapy with anti-IL-2R antibody. So far, in this group, VT has not been identified. In summary, a total of 14 out of 126 patients (11%) had isolated VT with a mean follow-up of 36.4 months. Based on our experience, we suggest that extensive VT after pancreas transplantation, including splenic and superior mesenteric VT, be treated with heparin and subsequent oral anticoagulation for 3 months. For more limited, partial splenic VT, aspirin may be sufficient. Follow-up CDU is critical for a successful outcome. The i.v. use of TAC appears to be a risk factor for the increased incidence of VT. Currently, using IL-2rmAb as induction, TAC is started orally on postoperative days 3 or 4 and aspirin on postoperative day 2. 相似文献
124.
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. 相似文献
125.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
126.
Talan DA Stamm WE Hooton TM Moran GJ Burke T Iravani A Reuning-Scherer J Church DA 《JAMA》2000,283(12):1583-1590
Context The optimal antimicrobial regimen and treatment duration for acute uncomplicated pyelonephritis are unknown. Objective To compare the efficacy and safety of a 7-day ciprofloxacin regimen and a 14-day trimethoprim-sulfamethoxazole regimen for the treatment of acute pyelonephritis in women. Design Randomized, double-blind comparative trial conducted from October 1994 through January 1997. Setting Twenty-five outpatient centers in the United States. Patients Of 378 enrolled premenopausal women aged at least 18 years with clinical diagnosis of acute uncomplicated pyelonephritis, 255 were included in the analysis. Other individuals were excluded for no baseline causative organism, inadequate receipt of study drug, loss to follow-up, no appropriate cultures, and other reasons. Interventions Patients were randomized to oral ciprofloxacin, 500 mg twice per day for 7 days (with or without an initial 400-mg intravenous dose) followed by placebo for 7 days (n = 128 included in analysis) vs trimethoprim-sulfamethoxazole, 160/800 mg twice per day for 14 days (with or without intravenous ceftriaxone, 1 g) (n = 127 included in the analysis). Main Outcome Measure Continued bacteriologic and clinical cure, such that alternative antimicrobial drugs were not required, among evaluable patients through the 4- to 11-day posttherapy visit, compared by treatment group. Results At 4 to 11 days posttherapy, bacteriologic cure rates were 99% (112 of 113) for the ciprofloxacin regimen and 89% (90 of 101) for the trimethoprim-sulfamethoxazole regimen (95% confidence interval [CI] for difference, 0.04-0.16; P = .004). Clinical cure rates were 96% (109 of 113) for the ciprofloxacin regimen and 83% (92 of 111) for the trimethoprim-sulfamethoxazole regimen (95% CI, 0.06-0.22; P = .002). Escherichia coli, which caused more than 90% of infections, was more frequently resistant to trimethoprim-sulfamethoxazole (18%) than to ciprofloxacin (0%; P<.001). Among trimethoprim-sulfamethoxazoletreated patients, drug resistance was associated with greater bacteriologic and clinical failure rates (P<.001 for both). Drug-related adverse events occurred in 24% of 191 ciprofloxacin-treated patients and in 33% of 187 trimethoprim-sulfamethoxazoletreated patients, respectively (95% CI, -0.001 to 0.2). Conclusions In our study of outpatient treatment of acute uncomplicated pyelonephritis in women, a 7-day ciprofloxacin regimen was associated with greater bacteriologic and clinical cure rates than a 14-day trimethoprim-sulfamethoxazole regimen, especially in patients infected with trimethoprim-sulfamethoxazoleresistant strains. 相似文献
127.
Andrea Carlson Gielen Karen A McDonnell Patricia J O'Campo Jessica Griffin Burke 《Women's health issues》2005,15(2):89-95
PURPOSE: This study examines the association between women's HIV serostatus, intimate partner violence (IPV) experience, and risk of suicide and other mental health indicators. Using data from Project WAVE (Women, AIDS, and the Violence Epidemic), we 1) describe the rates of suicidal thoughts and attempts, anxiety, and depression; 2) examine whether and to what extent these outcomes differ by women's HIV and IPV status. METHODS: A one-time interview was conducted with a sample 611 women living in an urban area, one-half of whom were HIV-positive. RESULTS: Having thought about suicide was reported by 31% of the sample and 16% reported having attempted suicide. Among HIV-positive women, thoughts of suicide occurred more frequently among those who were recently diagnosed. One-half of the sample reported problems with depression, and 26% reported problems with anxiety; of women reporting these problems, 56% received mental health treatment. Rates varied significantly by HIV and IPV status, with women who were both HIV-positive and abused consistently faring worse. Relative to HIV-negative non-abused women, HIV-positive abused women were 7.0 times as likely to report problems with depression, 4.9 times as likely to report problems with anxiety, 3.6 times as likely to have thought about suicide, and 12.5 times as likely to have ever attempted suicide. Our findings that abused HIV-negative women were also at significantly elevated risk for all of these outcomes lends support to the conclusion that it is the experience of abuse that is associated with the negative outcomes. CONCLUSIONS: Health care and service providers interacting with women who may be HIV-positive and/or in abusive relationships should routinely assess for mental health status, especially suicide risk, which may need crisis intervention. 相似文献
128.
129.
Miyaji K Hannan RL Ojito J Dygert JM White JA Burke RP 《The Annals of thoracic surgery》2000,70(3):730-737
BACKGROUND: Video-assisted thoracoscopic surgical techniques have been widely adopted as a means to reduce surgical trauma. By adapting pediatric thoracoscopic instrumentation, we have developed a technique for video-assisted cardioscopy (VAC). We report our experience and describe the technical feasibility of VAC. METHODS: Since June 1995, 409 consecutive patients underwent 431 intracardiac procedures (ventricular septal defect, 150; tetralogy of Fallot or double outlet right ventricle, 101; atrioventricular canal, 52; subaortic stenosis, 43; valve repair, 50; Rastelli procedure, 12; Konno or Ross Konno operation, 11; and miscellaneous, 12) using VAC at Miami Children's Hospital. Using a prospective database, we tracked outcomes and operative events to delineate the usefulness and efficacy of this technique. RESULTS: VAC provided clear and precise imaging of small or remote intracardiac structures during repair of congenital heart defects without technical complications. Procedure times and aortic cross-clamp times using VAC were not prolonged. Intraoperative images were collected for every operation, documenting each patient's cardiac anatomy before and after repair. Surgery through small incisions was facilitated. Operative mortality was 1.2% (5 of 409), and no patient required reoperation before discharge. At a mean follow-up interval of 22 months, the incidence of reoperation for residual or recurrent lesions was 1.2% (5 of 404). CONCLUSIONS: Our experience demonstrates the technical feasibility and clinical utility of routine endoscopic imaging during open heart surgery for congenital heart repair. 相似文献
130.
Evaluation of subsecond gated helical CT for quantification of coronary artery calcium and comparison with electron beam CT 总被引:26,自引:0,他引:26
Carr JJ Crouse JR Goff DC D'Agostino RB Peterson NP Burke GL 《AJR. American journal of roentgenology》2000,174(4):915-921
OBJECTIVE: Since its introduction early in the 1990s, helical CT has become the predominant technology for obtaining CT images for medical applications. Recent improvements in the temporal resolution of helical CT (subsecond) and the addition of retrospective cardiac gating are combined in this report evaluating cardiac-gated helical CT for quantifying coronary artery calcium. We compare total calcium scores determined on subsecond gated helical CT with the current reference for coronary calcium evaluation, electron beam CT. MATERIALS AND METHODS: We compared total calcium scores obtained using a general purpose, unmodified helical CT scanner with scores obtained using electron beam CT in 36 individuals who were 68+/-11 years old (age range, 41-85 years). RESULTS: Correlation coefficients ranged from 0.97 to 0.98 (Pearson's product moment) and from 0.95 to 0.96 (Spearman's rank order), depending on the coronary calcium scoring method used. Agreement in the classification of participants as "healthy" or "diseased" at threshold total calcium scores of 10, 100, 160, 200, 400, and 680 was, respectively, 94%, 97%, 89%, 92%, 94%, and 100% using the conventional electron beam CT scoring method and an equivalent method with helical CT. CONCLUSION: A general purpose, current generation helical CT scanner equipped for retrospective cardiac gating can accurately quantify coronary calcium, and the results are highly correlated to scores obtained with electron beam CT. As an alternative method for measuring coronary calcium, gated subsecond cardiac helical CT offers greater availability and lower cost, thereby making population-based screening for coronary artery calcium more feasible. 相似文献