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31.
BackgroundAnthracycline use in metastatic breast cancer (MBC) is hindered by cumulative exposure limits and risk of cardiotoxicity. Pixantrone, a novel aza-anthracenedione with structural similarities to mitoxantrone and anthracyclines, is theorized to exhibit less cardiotoxicity, mainly due to lack of iron binding. We conducted a randomized phase II study to evaluate the efficacy and safety of 2 dosing schedules of pixantrone in patients with refractory HER2-negative MBC.MethodsIntravenous pixantrone was administered at 180 mg/m2 every 3 weeks (group A) versus 85 mg/m2 on days 1, 8, and 15 of a 28-day cycle (group B). Primary endpoint was objective response rate (ORR) and secondary endpoints included progression-free survival (PFS), median 6-month PFS, overall survival (OS), safety, quality of life, and serial assessment of circulating tumor cells. A 20% ORR was targeted as sufficient for further testing of pixantrone in this patient population.ResultsForty-five patients were evaluable, with 2 confirmed partial responses in group A and 1 in group B. The trial was terminated due to insufficient activity. Overall median PFS and OS were 2.8 (95% confidence interval [CI]: 2.0-4.1) and 16.8 (95% CI: 8.9-21.6) months, respectively. Notable overall grade 3-4 adverse events were the following: neutrophil count decrease (62%), fatigue (16%), and decrease in ejection fraction (EF) (4%).ConclusionPixantrone has insufficient activity in the second- and third-line MBC setting. It appears, however, to have limited cardiotoxicity. (ClinicalTrials.gov ID: NCT01086605).  相似文献   
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BackgroundAnisakis simplex sensitization has been associated with acute, but also with chronic urticaria. The objective of this study is to characterize chronic urticaria with (CU +) and without sensitization (CU-) against the ubiquitous fish parasite A. simplex in a transversal and longitudinal evaluation.Methods16 CU + and 22 CU- patients were included and assessed for Urticaria activity score (UAS), fish-eating habits by standardized questionnaire and cytokine production (assessed by flow cytometric bead-based array) of peripheral blood mononuclear cells after stimulation with A. simplex extract or Concanavalin A (Con A). Patients were randomly put on a fish-free diet for three months and UAS, as well as cytokine production were again assessed. A difference of ≥ 1 in UAS was defined as improvement.ResultsThere was no difference in UAS in both groups. Anisakis induced IL-2, IL-4 and IFN-γ production was higher in CU +. Con A induced IL-6 and IL-10 production was higher in CU +. CU + was associated with higher total fish intake, whereas CU- was associated with oily fish intake. The correlation of UAS was positive with oily fish, but negative with total fish intake.There was a better UAS-based prognosis in CU + without diet. Improvement was associated with higher Con A induced IL-10/IFN-γ as well as IL-10/IL-6 ratios. Further, previous higher oily fish intake was associated with improvement.ConclusionsOur data confirm the different clinical and immunological phenotype of CU +. Our results show a complex relationship between fish-eating habits, cytokine production and prognosis, which could have important consequences in dietary advice in patients with CU. When encountering A. simplex sensitization, patients should not be automatically put on a diet without fish in order to reduce contact with A. simplex products.  相似文献   
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We report a transfusion trial of platelets photochemically treated for pathogen inactivation using the synthetic psoralen amotosalen HCl. Patients with thrombocytopenia were randomly assigned to receive either photochemically treated (PCT) or conventional (control) platelets for up to 28 days. The primary end point was the proportion of patients with World Health Organization (WHO) grade 2 bleeding during the period of platelet support. A total of 645 patients (318 PCT and 327 control) were evaluated. The primary end point, the incidence of grade 2 bleeding (58.5% PCT versus 57.5% control), and the secondary end point, the incidence of grade 3 or 4 bleeding (4.1% PCT versus 6.1% control), were equivalent between the 2 groups (P =.001 by noninferiority). The mean 1-hour posttransfusion platelet corrected count increment (CCI) (11.1 x 10(3) PCT versus 16.0 x 10(3) control), average number of days to next platelet transfusion (1.9 PCT versus 2.4 control), and number of platelet transfusions (8.4 PCT versus 6.2 control) were different (P <.001). Transfusion reactions were fewer following PCT platelets (3.0% PCT versus 4.4% control; P =.02). The incidence of grade 2 bleeding was equivalent for PCT and conventional platelets, although posttransfusion platelet count increments and days to next transfusion were decreased for PCT compared with conventional platelets.  相似文献   
36.
The VKORC1 c.-1639G>A and CYP2C9 c.430C>T and c.1075A>C polymorphisms have been associated with increased sensitivity to oral anticoagulants. However, their role in gastrointestinal bleeding is unknown. We studied the risk of gastrointestinal bleeding associated with these polymorphisms, and how this risk was influenced by the anticoagulant dose and the use of common drugs. Eighty-nine patients with gastrointestinal bleeding during acenocoumarol therapy and 177 patients free of bleeding during acenocoumarol therapy were studied. None of the three polymorphisms constituted a serious gastrointestinal bleeding risk factor. However, patients bearing at least one of these polymorphisms were at high risk, when they simultaneously met one of the following conditions: a weekly dose of acenocoumarol higher than 15 mg [adjusted Odds Ratio (OR) (95% confidence interval (CI) = 4.19 (1.59-11.04)]; amiodarone use [adjusted OR (95% CI) = 9.97 (1.75-56.89)]; or aspirin use [adjusted OR (95% CI) = 8.97 (1.66-48.34)]. The consumption of statins was associated with a lower risk of gastrointestinal bleeding [adjusted OR = 0.50 (0.26-0.99)]. The risk of gastrointestinal bleeding during acenocoumarol therapy in carriers of any of the studied polymorphisms is severely increased with exposure to weekly doses of acenocoumarol higher than 15 mg or the use of amiodarone or aspirin.  相似文献   
37.
PURPOSE: Despite having removed the whole macroscopic disease (curative intent surgery), one of five patients with Stages I and II colorectal cancer will develop recurrence. Lymphatic micrometastases detected by immunohistochemistry could be one of explanation for recurrence and cancer-related death in patients without lymph node involvement at light microscopy. However, the biologic importance of micrometastases remains unclear. This study was designed to determine the impact of micrometastases in five-year survival in patients with Stages I and II colorectal cancer.METHODS: This retrospective study included patients operated on between May 1989 and January 1999 for colorectal cancer without histopathologic lymph node involvement. Patients who received any adjuvant therapy were excluded. Immunohistochemical staining of the lymph nodes was performed with antipancytokeratin antibodies. Follow-up data were obtained from the clinical database and death certificates. Survival was estimated by the Kaplan-Meier method and compared by the log-rank test.RESULTS: Micrometastases were observed in 26 of 90 patients (28.9 percent). The mean follow-up time was 90.7 (range, 11–160) months. Seventeen cancer-related deaths occurred during follow-up (18.9 percent), 6 of them in patients with micrometastases (23.1 percent) and 11 in patients without micrometastases (17.2 percent; P = 0.559). Cancer-specific five-year survival was 87 percent in the whole group and 81 percent in patients positive for micrometastases vs. 90 percent in negative patients (P = 0.489).CONCLUSIONS: The presence of micrometastases in patients with Stages I and II colorectal cancer seems not to have any impact on cancer-specific survival.Supported by the Apertus Research Program (Andromaco Pharmaceutical Company) and by The National Public Grant (FONDECYT #1000556).  相似文献   
38.
Peutz-Jeghers syndrome is an autonomic dominant disease characterized by hamartomatous polyps and mucocutaneous hyperpigmentation. We present 16 cases; females were more affected. The most common presenting complaints were of gastrointestinal tract. All polyps found were hamartomatous with general distribution through gastrointestinal tract. Endoscopic polypectomy should be carried out for treatment. Radiologic, endoscopic and histologic studies should be conducted for long-term follow-up, because of high risk of malignancy.  相似文献   
39.
OBJECTIVE: To assess the medical care costs of hypertension and their impact on the health care expenditures and on Mexico's Gross National Product (GNP). MATERIAL AND METHODS: An ecological study was conducted from June to November 1999, at Instituto Mexicano del Seguro Social (Mexican Institute of Social Security, IMSS), in Monterrey, Nuevo Leon, Mexico. A random sample of medical charts of patients with hypertension was selected, to extract data on utilization of health services and unitary costs per care episode. The cost per care episode and per hypertensive patient was calculated by adjusting the unitary cost as a function of standard and extreme utilization of IMSS health services. The resulting figure was then projected to the total population of hypertensive patients and compared to the annual health care expenditures of Mexico. RESULTS: The annual cost per patient with hypertension was $1,067 in the standard scenario and $3,913 in the extreme scenario. The annual expenditures from hypertension corresponded to 13.95% of the budget allocated to health care and to 0.71%, of Mexico's GNP. These figures changed to 51.17% and 2.61% in the extreme scenario, respectively. CONCLUSIONS: The costs of hypertension medical care account for a good portion of healthcare resources. This problem should be analyzed by multidisciplinary health teams in search of more efficient medical care alternatives.  相似文献   
40.
We studied the association between CD34 cell dose and transplant outcomes in 359 bone marrow (BM) and 511 peripheral blood stem cell (PBSC) transplant recipients from human leucocyte antigen (HLA)-identical siblings, reported to the International Bone Marrow Transplant Registry (IBMTR). Transplants for leukaemia were performed between 1995 and 1998. Patients were divided into those receiving below or above the median CD34+ dose, for BM (3 x 106/kg) and PBSC (6 x 106/kg) grafts respectively. Cox proportional hazards regression was used to adjust for baseline patient-, disease- and transplant-related characteristics. Analysis of the BM recipients showed that high CD34 cell dose was associated with lower transplant-related mortality [relative risk (RR) = 0.60, P = 0.033] and treatment failure (inverse of leukaemia-free survival, RR = 0.69, P = 0.032). Among PBSC recipients, high CD34 dose was associated with faster recovery of neutrophils to > 0.5 x 109/l (RR = 1.38, P < 0.001) and platelets to > 20 x 109/l (RR = 1.34, P = 0.003), lower risk of relapse (RR = 0.62, P = 0.029) and treatment failure (RR = 0.74, P = 0.03). We conclude that higher CD34 cell doses decrease treatment failure in recipients of HLA-identical sibling BM and PBSC transplants.  相似文献   
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