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Cooperative Study (cooperative + study)
Selected AbstractsI. Veterans Affairs Cooperative Study of Polyenylphosphatidylcholine in Alcoholic Liver Disease: Effects on Drinking Behavior by Nurse/Physician TeamsALCOHOLISM, Issue 11 2003Charles S. Lieber Background: This multicenter prospective, randomized, double-blind placebo-controlled trial was designed to evaluate the effectiveness of polyenylphosphatidylcholine against the progression of liver fibrosis toward cirrhosis in alcoholics. Seven hundred eighty-nine alcoholics with an average intake of 16 drinks per day were enrolled. To control excessive drinking, patients were referred to a standard 12-step,based alcoholism treatment program, but most patients refused to attend. Accordingly, study follow-up procedures incorporated the essential features of the brief-intervention approach. An overall substantial and sustained reduction in drinking was observed. Hepatic histological and other findings are described in a companion article. Methods: Patients were randomized to receive daily three tablets of either polyenylphosphatidylcholine or placebo. Monthly follow-up visits included an extensive session with a medical nurse along with brief visits with a study physician (hepatologist or gastroenterologist). A detailed physical examination occurred every 6 months. In addition, telephone consultations with the nurse were readily available. All patients had a liver biopsy before entry; a repeat biopsy was scheduled at 24 and 48 months. Results: There was a striking decrease in average daily alcohol intake to approximately 2.5 drinks per day. This was sustained over the course of the trial, lasting from 2 to 6 years. The effect was similar both in early dropouts and long-term patients, i.e., those with a 24-month biopsy or beyond. Conclusions: In a treatment trial of alcoholic liver fibrosis, a striking reduction in alcohol consumption from 16 to 2.5 daily drinks was achieved with a brief-intervention approach, which consisted of a relative economy of therapeutic efforts that relied mainly on treatment sessions with a medical nurse accompanied by shorter reinforcing visits with a physician. This approach deserves generalization to address the heavy drinking problems commonly encountered in primary care and medical specialty practices. [source] Changing trends in pediatric transplantation: 2001 Annual Report of the North American Pediatric Renal Transplant Cooperative StudyPEDIATRIC TRANSPLANTATION, Issue 4 2003Mark R. Benfield This cooperative group now includes over 150 participating medical centers in the United States, Canada, Mexico, and Costa Rica. This report covers the years from 1987 through 2001 and includes data on 7545 renal transplants in 6878 patients. This report demonstrates changing trends in many areas of pediatric transplantation including increasing numbers of African American and Hispanic children receiving transplantation, remarkable improvements in the rate of acute rejection, rejection reversal, and short- and long-term allograft survival. In the most recent cohorts of patients, we now see that 1-yr allograft survival is no different in cadaver donor compared to living donor recipients and in infants compared to all other age groups. However, this analysis also reveals areas of continued challenges including inferior outcomes in African American and adolescent populations, chronic rejection, and the adverse effects of immunosuppression. [source] Mycophenolate mofetil without antibody induction in cadaver vs. living donor pediatric renal transplantationPEDIATRIC TRANSPLANTATION, Issue 2 2003O. Ojogho Abstract: Mycophenolate mofetil (MMF) is a new immunosuppressive agent that blocks de novo purine synthesis in T and B lymphocytes via a potent selective inhibition of inosine monophosphate dehydrogenase. MMF has been shown to significantly reduce the incidence of acute rejection in both adult and pediatric renal transplantation. The impact of MMF on routine antibody induction therapy in pediatric renal transplantation has not been defined. Remarkably, a recent North American Pediatric Transplant Cooperative Study concluded that T-cell antibody induction therapy was deleterious for patients who received MMF. Our study examines the use of MMF in an evolving immunosuppressive strategy to avoid antibody induction in both living (LD) and cadaver (CAD) donor pediatric renal transplantation. We retrospectively analyzed the records of 43 pediatric renal transplants that received MMF-based triple therapy without antibody induction therapy between November 1996 and April 2000. We compared CAD (n = 17) with LD (n = 26). The two groups were similar demographically except that CAD had significantly younger donors than LD, 26.1 ± 13.7 vs. 36.2 ± 9.2 yr (p = 0.006). All the patients received MMF at 600 mg/m2/b.i.d. (maximum dose of 2 g/d) and prednisone with cyclosporine (86%) or tacrolimus (14%). Mean follow-up was >36 months for each group. Acute rejection rate at 6 months was 11.8% (CAD) vs. 15.4% (LD) (p = 0.999) and at 1 yr was 23.5% (CAD) vs. 26.9% (LD) (p = 0.999). Mean estimated glomerular filtration rate (ml/min/1.73 m2) at 6 months was 73.3 ± 15.3 (CAD) vs. 87.6 ± 24.2 (LD) (p = 0.068). Patient survival at 1, 2, and 3 yr was 100, 100, and 100% for CAD vs. 100, 96, and 96% for LD, respectively. Graft survival at 1, 2, and 3 yr was 100, 100, and 94% for CAD vs. 96, 88, and 71% for LD, respectively. Graft loss in CAD was because of chronic rejection (n = 2) while in LD it was because of non-compliance (n = 6), post-transplant lymphoproliferative disorder (n = 1), and sepsis (n = 1). In conclusion, MMF without antibody induction in both CAD and LD pediatric renal transplantation provides statistically similar and effective prophylaxis against acute rejection at 6 months and 1 yr post-transplant. The short-term patient and graft survival rates are excellent, however, non-compliance remains a serious challenge to long-term graft survival. Additional controlled studies are needed to define the role of MMF without antibody induction therapy in pediatric renal transplantation. [source] Do six-antigen-matched cadaver donor kidneys provide better graft survival to children compared with one-haploidentical living-related donor transplants?PEDIATRIC TRANSPLANTATION, Issue 2 2000A report of the North American Pediatric Renal Transplant Cooperative Study Abstract: Since 1991, more than 50% of pediatric transplant recipients have received a living donor (LD) kidney, and , 85% of these allografts were one-haploidentical parental kidneys. Short-term (1 yr) and long-term (5 yr) graft survival of LD kidneys are 10% and 15% better, respectively, than that of cadaver donor (CD) kidneys. Because of these results, children are frequently not placed on a cadaver waiting list until the possibility of a LD is excluded , a process that may take up to 1 yr. The hypothesis for this study was that the graft outcome of a six-antigen-matched CD kidney is superior to that of a one-haploidentical LD kidney, and that children are at a disadvantage by not being placed on a CD list whilst waiting for a LD. The database of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) for 11 yrs (1987,98), was reviewed to identify children who were recipients of a six-antigen-matched CD kidney (primary and repeat transplants), and those who were recipients of a one-haploidentical LD kidney (primary and repeat transplants). Using standard statistical methods, the morbidity, rejection episodes, post-transplant hospitalizations, renal function, long- and short-term graft survival, and half-life of primary recipients were compared in the two groups. Unlike adult patients, only 2.7% (87/3313) of CD recipients in the pediatric age range received a six-antigen-matched kidney, and the annual accrual rate over 11 yrs was never higher than 4%. Comparison of 57 primary six-antigen-CD kidneys (PCD) with 2472 primary LD (PLD) kidneys revealed that morbidity, rejection rates, and ratios were identical in the two groups. Renal function and subsequent hospitalizations were also identical in the two groups. Five-year graft survival of the PCD group was 90% compared with 80% for the PLD group, and the half-life of the PCD group was 25 ± 12.9 yrs compared with 19.6 ± 1.3 yrs. Our data suggest that the six-antigen-matched CD kidney may have less graft loss as a result of chronic rejection and would therefore confer a better long-term outcome. Based on these findings we recommend that all children, whilst waiting for a LD work-up, be listed with the United Network for Organ Sharing (UNOS) registry for a CD kidney. [source] UGT1A1 promoter polymorphisms and the development of hyperbilirubinemia and gallbladder disease in children with sickle cell anemiaAMERICAN JOURNAL OF HEMATOLOGY, Issue 10 2008Shannon L. Carpenter Genetic modifiers contribute to phenotypic variability in patients with sickle cell anemia (SCA). The influence of the bilirubin UDP-glucuronosyltransferase (UGT) 1A1 (TA)nTAA promoter polymorphism on bilirubin levels and gallbladder disease in SCA was examined using prospectively collected data from the Cooperative Study of Sickle Cell Disease. A total of 324 children with HbSS (median age 6.9 years) had UGT1A1 genotyping; 243 (75%) had common (TA)6 or (TA)7 alleles, whereas 81 (25.0%) had variant (TA)5 or (TA)8 alleles. The UGT1A1 genotype significantly influenced average bilirubin levels for the common alleles: 6/6 genotype = 2.36 ± 1.13 mg/dL, 6/7 genotype = 2.90 ± 1.54 mg/dL, and 7/7 genotype = 4.24 ± 2.11 mg/dL (P < 0.0001). Thirty-nine percent of children with the 7/7 genotype had documented gallbladder disease, compared with 18.2% with the 6/7 genotype and only 9.9% with the wildtype 6/6 UGT1A1 genotype (P = 0.001). To analyze the (TA)5 and (TA)8 variant alleles, three groups were generated, showing increasing bilirubin levels with increasing TA repeats and age. Group 3 (genotypes 6/8, 7/7, and 7/8) had a significantly greater rate of bilirubin change than Groups 1 (genotypes 5/6, 5/7, and 6/6) or 2 (genotype 6/7). These results validate previous smaller studies and confirm that the UGT1A1 promoter polymorphism exerts a powerful influence on bilirubin levels and the development of gallbladder disease in children with SCA. UGT1A1 genotyping should be considered as a screening tool for predicting children most likely to develop gallbladder disease at a young age. Am. J. Hematol., 2008. © 2008 Wiley-Liss, Inc. [source] Recurrent spreading depolarizations after subarachnoid hemorrhage decreases oxygen availability in human cerebral cortexANNALS OF NEUROLOGY, Issue 5 2010Bert Bosche MD Objective Delayed ischemic neurological deficit (DIND) contributes to poor outcome in subarachnoid hemorrhage (SAH) patients. Because there is continuing uncertainty as to whether proximal cerebral artery vasospasm is the only cause of DIND, other processes should be considered. A potential candidate is cortical spreading depolarization (CSD)-induced hypoxia. We hypothesized that recurrent CSDs influence cortical oxygen availability. Methods Centers in the Cooperative Study of Brain Injury Depolarizations (COSBID) recruited 9 patients with severe SAH, who underwent open neurosurgery. We used simultaneous, colocalized recordings of electrocorticography and tissue oxygen pressure (ptiO2) in human cerebral cortex. We screened for delayed cortical infarcts by using sequential brain imaging and investigated cerebral vasospasm by angiography or time-of-flight magnetic resonance imaging. Results In a total recording time of 850 hours, 120 CSDs were found in 8 of 9 patients. Fifty-five CSDs (,46%) were found in only 2 of 9 patients, who later developed DIND. Eighty-nine (,75%) of all CSDs occurred between the 5th and 7th day after SAH, and 96 (80%) arose within temporal clusters of recurrent CSD. Clusters of CSD occurred simultaneously, with mainly biphasic CSD-associated ptiO2 responses comprising a primary hypoxic and a secondary hyperoxic phase. The frequency of CSD correlated positively with the duration of the hypoxic phase and negatively with that of the hyperoxic phase. Hypoxic phases significantly increased stepwise within CSD clusters; particularly in DIND patients, biphasic ptiO2 responses changed to monophasic ptiO2 decreases within these clusters. Monophasic hypoxic ptiO2 responses to CSD were found predominantly in DIND patients. Interpretation We attribute these clinical ptiO2 findings mainly to changes in local blood flow in the cortical microcirculation but also to augmented metabolism. Besides classical contributors like proximal cerebral vasospasm, CSD clusters may reduce O2 supply and increase O2 consumption, and thereby promote DIND. ANN NEUROL 2010;67:607,617 [source] | ||||||||||