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1.
Biotransformation of caffeine and theophylline and the effect of two well-known inducers of P-450 isozymes, namely phenobarbital (PB) and methylcholanthrene (3-MC) were studied in cultured hepatocytes from six human adult donors. Hepatocytes co-cultured with rat liver epithelial cells maintained a higher metabolic capacity than pure cultures. PB treatment of cultured hepatocytes for 3 days slightly increased the rate of caffeine metabolism 1.4 +/- 0.5-fold (N = 6) vs controls, and theophylline metabolism 1.2 +/- 0.4-fold (N = 6), whereas 3-MC treatment increased metabolism markedly 5.8 +/- 2.3- and 3.3 +/- 1.1-fold (N = 6) vs controls for caffeine and theophylline, respectively. Paraxanthine and theophylline formations from caffeine were the most induced by 3-MC. Their increase was significantly correlated (rs = 0.89, P less than 0.007) but not with TB formation, suggesting that at least two isozymes of the P-450IA family are involved in the first demethylations of caffeine. In addition, the N-1 demethylation of theophylline (mean increase of 554% vs controls) was not correlated with the N-1 demethylation of caffeine (mean to increase 247% vs controls) for the same donor after 3-MC treatment, suggesting that these two demethylations are mediated by a different P-450.  相似文献   
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Jumping translocations (JT) have been defined as nonreciprocal translocations involving a same donor chromosome arm or chromosome segment onto two or more recipient chromosomes in different cell lines in the same patient, leading to a mosaic karyotype. This definition has been expanded to also include extra copies of a same donor segment on different recipient chromosomes in a single clone. Six patients with multiple myeloma and JT involving chromosome arm 1q were identified among 37 patients presenting with chromosome 1 abnormalities. All six patients had an advanced disease and a short survival. The literature review allowed us to identify 24 additional patients with JT. Chromosomes 16 and 19 were the recipients in 11 (45.8%) and 6 (25%) of these 24 patients, respectively. Breakpoints on the recipient chromosomes were pericentromeric in 46.2% and telomeric in 40.4% of the breakpoints recorded. Since telomeres are made of (TTAGGG)n tandem DNA repeats that are also found in the pericentromeric heterochromatic regions (interstital telomeric sequences), it is presumed that jumping translocations arise through illegimate recombination between telomere repeat sequences and interstitial telomeric sequences.  相似文献   
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Elective laparoscopic management of sigmoid diverticulitis   总被引:6,自引:2,他引:4  
BACKGROUND: The aim of this study was to evaluate the results of elective laparoscopic treatment of sigmoid diverticulitis. METHODS: Between November 1991 and February 1998, 110 patients were treated by elective laparoscopic colectomy for sigmoid diverticulitis. The main data recorded were postoperation pain, return of bowel function, operation time, duration of hospital stay, and early and late complications. RESULTS: Mean age of patients was 63 years (range, 36-83 years). Nine patients (8.2%) required conversion to laparotomy because of severe adhesions, inflammatory process, or obesity. The mean operation time was 167 min. Return of bowel function was 2.3 days. Mean postoperation stay was 8.2 days. There was no perioperation death, and the morbidity rate was 7.3%, with two complications related to the laparoscopic approach (1 trocar site bowel incarceration and 1 small bowel fistula). Of the patients with complications, four (3.6%) needed reoperation. During the follow-up (6-79 months), no incisional hernia was observed. CONCLUSIONS: Laparoscopic colectomy for sigmoid diverticulitis is feasible and safe in more than 90% of cases. Benefits of the laparoscopic approach are the improved early postoperation course and the reduction of parietal sequelae.  相似文献   
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A phase III prospective randomized multicenter study was performed to determine whether quinine could improve the response rate of poor-risk acute leukemias (ALs) to standard chemotherapy including a multidrug resistance (MDR)-related cytotoxic agent. The rationale of the study was based on the negative prognostic value of MDR phenotype in ALs and the ability of quinine to reverse this phenotype both in vitro and ex vivo. Three hundred fifteen patients (median age, 49 years; range, 16 to 65) with relapsed (n = 108) or refractory (n = 32) acute myeloblastic leukemia (AML), relapsed (n = 27) or refractory (n = 9) acute lymphoblastic leukemia (ALL), secondary AL (n = 22) or blastic transformation of myelodysplastic syndrome ([MDS] n = 74) or myeloproliferative syndrome ([MPS] n = 43) were randomly assigned to receive mitoxantrone ([MXN] 12 mg/m2/d, days 2 to 5) and cytarabine ([Ara-C] 1 g/m2/12 h, days 1 to 5) alone or in combination with quinine (30 mg/kg/d, days 1 to 5; continuous intravenous infusion beginning 24 hours before MXN infusion). Side effects of quinine were observed in 56 of 161 quinine-treated patients and disappeared in all but four cases after one or two 20% dose decreases. Sera from quinine-treated patients showed increased MXN uptake in an MDR-positive cell line compared with matched sera obtained before quinine infusion. Quinine induced a significant increase in the incidence of nausea, vomiting, mucositis, and cardiac toxicity. A complete response (CR) was observed in 85 of 161 patients (52.8%) from the quinine-treated group versus 70 of 154 patients (45.5%) in the control group (P = .19). The most important differences between quinine and control group CR rates were observed in patients with refractory AMLs and blastic transformation of MDS and MPS. The CR rate was higher in P-glycoprotein-positive cases, although the difference was not significant. Failure of the regimen due to blastic persistence or blast number increase was higher in the control group (61 of 154 patients) than in the quinine group (45 of 161, P = .04). Early death was observed in eight cases (four in each arm) and death in aplasia in 27 cases (20 in quinine group v seven in control group, P = .01). The significant increase of toxicity in the quinine arm could have masked the clinical benefit of MDR reversion in poor- risk ALs.  相似文献   
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OBJECTIVE: To analyse retrospectively the results of one-stage laparoscopic treatment for common bile duct stones in 19 surgical centers in France. PATIENTS: From January 1991 to July 1996, 612 patients with choledocholithiasis underwent laparoscopic treatment. RESULTS: Overall duct clearance was obtained in 489 of the 612 patients (80%): through the cystic duct in 222 of 380 patients (58.4%), by secondary choledochotomy (after unsuccessful transcystic duct extraction) in 77 of 96 (80%), and in 190 of 232 (82 %) by primary choledochotomy. The overall duct clearance rate increased from 65% in 1991 to 84% in 1996. The use of the choledochotomy approach increased from 43% in 1991 to 69% in 1996 (P<0.01), due to a substantial increase in primary choledochotomy. In contrast, the use of the transcystic approach decreased from 57% to 31% (P<0.01). The mean time for surgery was shorter for cystic duct exploration than for primary choledochotomy (101+/-51 vs. 155+/-62 min, P<0.0001). The mean hospital stay decreased from 7.7+/-3.6 days in 1991 to 4.1+/-2 days in 1996 (P<0.001). The main biliary complications were related to biliary drainage (2,8%) and retained stones (3.1%). CONCLUSION: This study confirms that laparoscopy is a good alternative with a low complication rate, a short hospital stay, and is an effective and safe option for the management of common bile duct stones.  相似文献   
8.
The LAM2001 phase 3 trial, involving 832 patients with acute myeloid leukemia (AML; median: 46 years) proposed HLA-identical sibling allograft HSCT for all patients with an identified donor. The trial compared reduced-intensity conditioning (RIC) for patients older than 50 years of age (N = 47) and myeloablative conditioning for younger patients (N = 117). BM HSCT was performed in the younger patients, while the older ones received a consolidation course, followed by peripheral blood allo-HSCT using RIC. The incidence of grade II-IV acute GVHD, was 51.9% (95% confidence interval [CI]: 42.1-61.8) and 11.3% (1.6-21.2) after myeloablative or RIC, respectively (P < .0001) and that of chronic GVHD 45.8% (95% CI: 34.8-56.7) and 41.7% (24.7-58.6; NS). Cumulative incidence of nonrelapse mortality at 108 months was 15.8% (95% CI: 9.8-23.2) for myeloablative, and 6.5% (0.2-16.2) for RIC (NS). CI of relapse at 108 months was 21.7% (95% CI: 13.9-28.6) and 28.6% (16.5-43.4; NS). Overall survival at 108 months was 63.4% (95% CI: 54.6-72.2) and 65.8% (52.2-72.2), respectively, after myeloablative or RIC (NS). RIC peripheral blood stem cell allo-HSCT is prospectively feasible for patients between the ages of 51 and 60 years without excess of relapse or nonrelapse mortality, and compares favorably with myeloablative marrow allo-HSCT proposed to younger patients.  相似文献   
9.
This multicentre prospective randomised trial compared the efficacy and safety of two doses of thalidomide in patients with relapsed or refractory myeloma. The study was designed to test the non-inferior efficacy and to confirm the better tolerability of low-dose thalidomide as compared to a higher dose. Four hundred patients were randomly assigned to receive either 100 or 400 mg/day of thalidomide. Dexamethasone treatment was added in both arms for patients with stable disease or treatment failure at 12 weeks. The primary endpoint was 1-year overall survival (OS). Thalidomide 100 mg/day was better tolerated than 400 mg/day with less high-grade somnolence, constipation, nausea/vomiting and peripheral neuropathy (P < 0.001, P = 0.007, P = 0.03 and P = 0.007, respectively). In the per-protocol population (PP), the estimated 1-year OS rates were of 74.5% (n = 149) and 67.3% (n = 156) in the 400 and 100 groups, respectively. The upper limit of the difference between these rates was of 15.6% higher than the non-inferiority acceptable limit of 12.75%, and the hypothesis of non-inferiority of 100 could not be established (P = 0.14). On the other hand, when intent-to-treat (ITT) population was analysed, the non-inferiority was demonstrated because the 1-year OS rates were of 72.8% (n = 195) and 68.8% (n = 205) in the same groups, leading to an upper limit of the difference of 11.49% lower than the non-inferiority acceptable limit. In addition, in patients alive 12 weeks postrandomisation and those who received thalidomide plus dexamethasone, there were no significant differences in response rates, time to progression, progression-free survival and OS between the two groups. Collectively, low-dose thalidomide 100 mg/day has significant activity in advanced myeloma with an improved safety profile and can be a good salvage therapy in combination with dexamethasone.  相似文献   
10.
High and low alcohol sensitivity (HAS and LAS) rats have been selected for their differences in ethanol-induced sleep time. Liver monooxygenase activities were studied in HAS and LAS rats before and after treatments with known inducers such as chronic ethanol, pyrazole, 3-methylcholanthrene (3-MC) and phenobarbital (PB) to determine whether the selection procedure also selected for differences in the cytochrome P-450 (P-450) inducibility. This previously has been shown with long sleep (LS) and short sleep (SS) mice, which were selected using a similar criterion. 3-MC and PB, in conjunction with chronic ethanol treatment, were used in order to evaluate the interactions of ethanol with these inducers. Prior to treatment, total P-450 content was slightly lower in LAS than in HAS rats. However, both lines displayed the same microsomal monooxygenase activities related to different P-450 isozymes. This was demonstrated by ethoxyresorufin deethylation (EROD) for cytochrome P-450 1A1 (CYP1A1), acetanilide hydroxylation (ACET) for CYP1A2, pentoxyresorufin dealkylation (PROD) for CYP2B, 1-butanol oxidation (BUTAN) and N-nitrosodimethylamine demethylation (NDMA) for CYP2E1. After the different treatments, HAS rats did not differ from LAS rats in their CYP2E1 inducibility. However, pyrazole, PB and 3-MC treatment led to differences in CYP1A and CYP2B monooxygenase activities between the two lines. The enhancement of PROD by pyrazole treatment was less prominent in LAS (1.7-fold of the control value) than in HAS rats (3.8-fold).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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