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51.
PURPOSE: To determine the activity of decitabine, a DNA methylation inhibitor, in imatinib-refractory or intolerant chronic myelogenous leukemia. MATERIALS AND METHODS: Thirty-five patients were enrolled in this phase II study (12 in chronic phase, 17 in accelerated phase, and six in blastic phase). Decitabine was administered at 15 mg/m2 intravenously over 1 hour daily, 5 days a week for 2 weeks. DNA methylation was measured using a LINE1 bisulfite/pyrosequencing assay. RESULTS: Complete hematologic responses were seen in 12 patients (34%) and partial hematologic responses in seven patients (20%), for an overall hematologic response rate of 54% (83% in chronic phase, 41% in accelerated phase, and 34% in blastic phase). Major cytogenetic responses were observed in six patients (17%), and minor cytogenetic responses were seen in 10 patients (29%) for an overall cytogenetic response rate of 46%. Median response duration was 3.5 months (range, 2 to 13+ months). Myelosuppression was the major adverse effect, with neutropenic fever in 28 (23%) of 124 courses of therapy. LINE1 methylation decreased from 71.3% +/- 1.4% (mean +/- standard error of the mean) to 60.7% +/- 1.4% after 1 week, 50.9% +/- 2.4% after 2 weeks, and returned to 66.5% +/- 2.7% at recovery of counts (median, 46 days). LINE1 methylation at the end of week 1 did not correlate with subsequent responses. However, at day 12, the absolute decrease in methylation was 14.5% +/- 3.0% versus 26.8% +/- 2.7% in responders versus nonresponders (P = .007). CONCLUSION: Decitabine induces hypomethylation and has clinical activity in imatinib refractory chronic myelogenous leukemia. We hypothesize that the inverse correlation between hypomethylation 2 weeks after therapy and response is due to a cell death mechanism of response, whereby resistant cells can withstand more hypomethylation.  相似文献   
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PURPOSE: To evaluate the efficacy of reduced intensity conditioning (RIC) allogeneic transplant in 30 patients with poor-prognosis chronic lymphocytic leukemia (CLL) and/or high-risk molecular/cytogenetic characteristics. EXPERIMENTAL DESIGN: Eighty-three percent of patients had active disease at the moment of transplant. That is, 14 of the 23 patients analyzed (60%) had unmutated immunoglobulin variable heavy-chain gene (IgV(H)) status; 8 of 25 patients (32%) had 11q-, with four of them also displaying unmutated IgV(H); and six (24%) had 17p- (five were also unmutated). RESULTS: After a median follow-up of 47.3 months, all 22 patients alive are disease free; overall survival and event-free survival (EFS) at 6 years were 70% and 72%, respectively. According to molecular/cytogenetic characteristics, overall survival and EFS for unmutated CLL and/or with 11q- aberration (n = 13) were 90% and 92%, respectively, not significantly different to those with normal in situ hybridization, 13q- and +12, or mutated CLL (n = 7). All six patients with 17p deletion were transplanted with active disease, including three with refractory disease; all except one reached complete remission after the transplant and two are alive and disease free. Nonrelapse mortality (NRM) was 20%; more than two lines before transplant is an independent prognostic factor for NRM (P = 0,02), EFS (P = 0.02), and overall survival (P = 0.01). Patients older than 55 years have a higher risk of NRM (hazard ratio, 12.8; 95% confidence interval, 1.5-111). Minimal residual disease was monitored by multiparametric flow cytometry in 21 patients. Clearance of CD79/CD5/CD19/CD23 cells in bone marrow was achieved in 68% and 94% of the patients at days 100 and 360, respectively. CONCLUSION: According to these results, RIC allogeneic transplant could overcome the adverse prognosis of patients with unmutated CLL as well as those with 11q- or 17p-.  相似文献   
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PURPOSE: Cloretazine (VNP40101M) is a novel sulfonylhydrazine alkylating agent with significant antileukemia activity. A phase I study of cloretazine combined with cytarabine (1-beta-d-arabinofuranosylcytosine, ara-C) was conducted in patients with refractory disease. DESIGN: Ara-C was given i.v. at a fixed dose of 1.5 gm/m(2)/d by continuous infusion for 4 days (patients ages <65 years at time of diagnosis) or 3 days (patients ages > or =65 years). Cloretazine was given i.v. over 15 to 60 minutes on day 2 at a starting dose of 200 mg/m(2), with escalation in 100 mg/m(2) increments in cohorts of three to six patients until a maximum tolerated dose was established. The DNA repair enzyme O(6)-alkylguanine DNA alkyltransferase (AGT) was measured at baseline. RESULTS: Forty patients, including 32 with acute myeloid leukemia, received 47 courses of treatment. Complete responses were seen at cloretazine dose levels of > or =400 mg/m(2) in 10 of 37 (27%) evaluable patients, and in this patient subset, AGT activity was significantly lower in patients that responded to treatment than in patients who did not (P < or = 0.027). Dose-limiting toxicities (gastrointestinal and myelosuppression) were seen with 500 and 600 mg/m(2) of cloretazine combined with the 4-day ara-C schedule but not seen with the 3-day schedule. CONCLUSION: The recommended cloretazine dose schedule for future studies is 600 mg/m(2) combined with 1.5 gm/m(2)/d continuous infusion of ara-C for 3 days. The cloretazine and ara-C regimen has significant antileukemic activity. AGT activity may be a predictor of response to cloretazine.  相似文献   
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Background:Emerging data highlight the interactions of preadmission glycemia, reflected by admission HbA1c levels, glycemic control during critical illness, and mortality. The association of preadmission insulin treatment with outcomes is unknown.Methods:This observational cohort study includes 5245 patients admitted to the medical-surgical intensive care unit of a university-affiliated teaching hospital. Three groups were analyzed: patients with diabetes with prior insulin treatment (DM-INS, n = 538); patients with diabetes with no prior insulin treatment (DM-No-INS, n = 986); no history of diabetes (NO-DM, n = 3721). Groups were stratified by HbA1c level: <6.5%; 6.5%-7.9% and >8.0%.Results:Among the three strata of HbA1c, mean blood glucose (BG), coefficient of variation (CV), and hypoglycemia increased with increasing HbA1c, and were higher for DM-INS than for DM-No-INS. Among patients with HbA1c < 6.5%, mean BG ≥ 180 mg/dL and CV > 30% were associated with lower severity-adjusted mortality in DM-INS compared to patients with mean BG 80-140 mg/dL and CV < 15%, (P = .0058 and < .0001, respectively), but higher severity-adjusted mortality among DM-No-INS (P = .0001 and < .0001, respectively) and NON-DM (P < .0001 and < .0001, respectively). Among patients with HbA1c ≥ 8.0%, mean BG ≥ 180 mg/dL was associated with lower severity-adjusted mortality for both DM-INS and DM-No-INS than was mean BG 80-140 mg/dL (p < 0.0001 for both comparisons).Conclusions:Significant differences in mortality were found among patients with diabetes based on insulin treatment and HbA1c at home and post-admission glycemic control. Prospective studies need to confirm an individualized approach to glycemic control in the critically ill.  相似文献   
58.
The ability of infants with protein-energy malnutrition to absorb iron was assessed using the serum iron response to a dose of ferrous sulfate providing 3 mg elemental iron per kg body weight. Responses were grouped as flat (delta serum Fe less than 30 microgram/dl), intermediate (30 to 100 microgram/dl), and normal (greater the 100 microgram/dl). Of 25 consecutively admitted children studied, seven had a flat, five an intermediate, and 13 a normal curve (mean delta serum Fe: 10 microgram/dl, 66 microgram/dl, and 175 microgram/dl, respectively). There were no differences among the three groups in hematocrit, fasting serum iron or transferrin saturation, severity of malnutrition, or evidence of other malabsorption sufficient to explain these differences. Although hematocrits, fasting serum iron, and transferrin saturations did not change appreciably during nutritional rehabilitation, all children with initially abnormal responses subsequently had normal tests.  相似文献   
59.
The heat treatment of a metal is a set of heating and cooling cycles that a metal undergoes to change its microstructure and, therefore, its properties. Temperature–time–transformation (TTT) diagrams are an essential tool for interpreting the resulting microstructures after heat treatments. The present work describes a novel proposal to predict TTT diagrams of the γ phase for the Ni-Al alloy using artificial neural networks (ANNs). The proposed methodology is composed of five stages: (1) database creation, (2) experimental design, (3) ANNs training, (4) ANNs validation, and (5) proposed models analysis. Two approaches were addressed, the first to predict only the nose point of the TTT diagrams and the second to predict the complete curve. Finally, the best models for each approach were merged to compose a more accurate hybrid model. The results show that the multilayer perceptron architecture is the most efficient and accurate compared to the simulated TTT diagrams. The prediction of the nose point and the complete curve showed an accuracy of 98.07% and 86.41%, respectively. The proposed final hybrid model achieves an accuracy of 96.59%.  相似文献   
60.
BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has affected care for diseases like cancer. The aim was to evaluate the impact of COVID-19 on waiting times for diagnosis and treatment of prostate cancer (PC), as well as the possible effect on the treatment results in PC patients undergoing radical prostatectomy.MethodsWe compared the results of 497 patients who underwent biopsy prior to the COVID-19 pandemic (1 January–31 December 2019) with those of 290 patients biopsied during the COVID-19 pandemic (1 January–31 December 2020). Demographic data, tumour characteristics, type of treatment and diagnosis times were comparable. Prostate specific antigen (PSA) levels were recorded at consultation prior to biopsy and after treatment. Mann-Whitney and chi-square tests were used to compare continuous variables and percentages, respectively.ResultsIn 2020, there were fewer urology consultations (35,160 vs. 40,225 in 2019). The median PSA in 2020 was significantly higher (14.3 vs. 9.9 ng/dL in 2019). In 2019, 53.1% (N=264) of the biopsies were positive for cancer vs. 47.2% (N=137) in 2020 (P=0.104). In 2020, more patients presented with metastatic disease (7.3% vs. 1.9%, P=0.009). Also, in 2020 there was a longer waiting time for prostate biopsy (42.1 vs. 35.3 days in 2019, P=0.019). A total of 132 patients underwent laparoscopic radical prostatectomy (LARP). The median time until surgery was similar in both years (71.9 vs. 58.29 days). During 2020, a higher percentage of patients had ISUP grade 4 in the surgical specimen (34.3% vs. 17.5%, P=0.07). Furthermore, a higher percentage of aggressive (pT3) tumours were diagnosed (37.2% vs. 27.2%, P=0.08), and the percentage of patients with involvement of surgical margins was also higher (48.6% vs. 29.3%, P=0.027). There were no differences between the groups in terms of biochemical recurrence or persistent PSA at one year (P=0.711).ConclusionsDelayed biopsy during the COVID-19 period did not appear to adversely impact biopsy results. Patients biopsied in 2020 had higher PSA, possibly due to proper triaging. A higher rate of adverse pathology outcomes was observed in patients undergoing radical prostatectomy during the pandemic, probably due to understaging of the biopsy. This study serves to raise awareness of the risk of deterioration of care of PC patients due to possible underdiagnosis.  相似文献   
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