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91.
Hans Gelderblom Ramon Salazar Jaap Verweij George Pentheroudakis Maja J A de Jonge Martin Devlin Christel van Hooije Francis Seguy Rosendo Obach Joan Pru?onosa Paola Principe Chris Twelves 《Clinical cancer research》2003,9(11):4101-4107
PURPOSE: Diflomotecan (BN80915) is an E-ring modified camptothecin analogue that possesses greater lactone stability in plasma compared with other topoisomerase I inhibitors, a potential advantage for antitumor activity. As with other camptothecins, oral administration has pharmacological and clinical advantages. This Phase I study was performed to assess the feasibility of the administration of oral diflomotecan, to determine the maximum-tolerated, dose its bioavailability, and to explore the pharmacokinetics. EXPERIMENTAL DESIGN: An initial i.v. bolus was administered to assess the bioavailability of diflomotecan. Fourteen days later, diflomotecan was administered p.o. once daily for 5 days to adult patients with solid malignant tumors and repeated every 3 weeks. BN80915 and its open lactone form BN80942 were measured. RESULTS: Twenty-two patients entered the study and received a total of 57 cycles of oral diflomotecan at flat dose levels of 0.10, 0.20, 0.27, and 0.35 mg. The main toxicity was hematological, but some patients experienced alopecia, mild gastrointestinal toxicity, and fatigue. At the 0.35-mg dose level, 2 of 4 patients experienced dose-limiting toxicity comprising grade 3 thrombocytopenia with epistaxis and febrile neutropenia in 1 patient and uncomplicated grade 4 neutropenia lasting for >7 days in another. Toxicity was acceptable at the 0.27-mg dose level at which dose-limiting toxicities were observed in 3 of 12 patients (grade 4 neutropenia > 7 days, complicated by fever in 1 patient but without other signs of infection). After two cycles of diflomotecan, 6 patients had disease stabilization, which was maintained in 2 patients for 9 months and >1 year, respectively. Diflomotecan pharmacokinetics were linear over the dose range studied. Systemic exposure correlated with the fall in WBC counts. The mean oral bioavailability (+/-SD) was 72.24 +/- 59.2% across all dose levels. Urinary excretion of BN80915 was very low. CONCLUSIONS: The recommended oral diflomotecan dose for Phase II studies is 0.27 mg/day x 5 every 3 weeks. This regimen is convenient and generally well tolerated with a favorable pharmacokinetic profile and high but variable bioavailability. 相似文献
92.
Treatment of oesophageal cancer with preoperative chemoradiotherapy may increase operative mortality
J. Balart J. Balmaa X. Rius R. Salazar M. Gallen S. Navarro A. Arcusa E. Gallardo J. Brunet 《European journal of surgical oncology》2003,29(10):884-889
AIMS: This phase II multicentric study evaluates a modified preoperative chemoradiotherapy schedule. METHODS: Patients <75 years with potentially resectable neoplasm were eligible. Treatment included an initial course of CDDP 100 mg/m2 (Day 1) and 5-FU CI 5000 mg/m2 (Days 1-5) followed by 45 Gy (Days 28-63) and 5-FU CI 5000 mg/m2 (Days 28-33), CDDP 75 mg/m2 (Day 56) and 5-FU CI 3750 mg/m2 (Days 56-61). Regional lymph nodes were irradiated. RESULTS: Nineteen patients were studied. Oesophagectomy was performed in 17. Clear margins were achieved in 16 of these. Eight patients showed a pathologic complete response (pCR). One patient died of infection during the preoperative treatment and four died due to acute surgical complications. The study was closed prematurely because of excessive mortality. Median follow-up was 19 months. Local and regional relapse occurred in one and three patients, respectively. Median time and actuarial 3-year of overall survival and progression free rates were 18.6 months and 28%, and 12.7 months and 10.4%, respectively. CONCLUSIONS: This schedule showed a high pCR, resectability and local control rate. Treatment-related mortality limits its clinical applicability, but further investigations are warranted. 相似文献
93.
Left Ventricular Anomalous Muscle Band and Electrocardiographic Repolarization Changes 总被引:6,自引:0,他引:6
J. Salazar 《Pediatric cardiology》1997,18(6):434-436
A child with considerable electrocardiographic (ECG) repolarization abnormalities is reported in whom, after clinical and
hemodynamic evaluation, only a large muscular false tendon within the left ventricular cavity was found. The genesis of the
ECG changes in such cases is discussed, and the differential diagnosis from apical hypertrophic cardiomyopathy is analyzed. 相似文献
94.
Keith D Salazar Patricia de la Rosa John B Barnett Rosana Schafer 《Toxicological sciences》2005,87(1):123-133
Propanil (3,4-dichloropropionanilide) and 2,4-D (2,4-dichlorophenoxyacetic acid) are commonly used herbicides that have toxic effects on the immune system. The present study determined the effect of exposure to these chemicals on the immune response to a bacterial vaccine. The antibody responses to the T-independent type 2 antigen, phosphorylcholine (PC) and the T-dependent antigen, pneumococcal surface protein A (PspA) were characterized in C57BL/6 mice after heat-killed Streptococcus pneumoniae (HKSP) immunization and single or mixture herbicide exposure. Propanil exposure significantly increased the number of PC-specific IgM, IgG2b, and IgG3 antibody-secreting B cells (ASC) in the spleen 4-6-fold over control animals in a dose-dependent manner. However, the number of ASC in the bone marrow and serum titers were comparable in control and propanil-treated mice. In contrast, 2,4-D exposure decreased the number of PC-specific IgM and IgG bone marrow ASC 2-3-fold from control animals. The decrease in bone marrow ASC in 2,4-D-treated mice corresponded to a 3-4-fold decrease in PC-specific IgM, IgG2b, and IgG3 serum titers compared to control mice. The number of ASC in the spleens of 2,4-D-treated mice was, however, comparable to control mice. The antibody response to PspA was not affected by any of the treatments. There were no mixture interactions between the two herbicides in any of the responses measured. These results characterize the primary PC-specific antibody response in the bone marrow, spleen, and serum after HKSP vaccination and herbicide exposure. The differential effects of propanil and 2,4-D on the antibody response to a bacterial vaccine demonstrate the potential of chemical exposure to augment or suppress immune responses to vaccines and infectious diseases. 相似文献
95.
José Rosselló-Urgell Josep Vaqué-Rafart Eduardo Hermosilla-Pérez Alejandro Allepuz-Palau 《Infection control and hospital epidemiology》2004,25(1):41-46
OBJECTIVE: To analyze a method that identifies potentially preventable nosocomial infections, as a tool to evaluate the performance of infection control programs through quantification of their potential for reducing nosocomial infections. METHODS: The database of the Study of the Prevalence of Nosocomial Infections in Spain (EPINE) was reanalyzed. The method was based on the use of false negatives of the classification table obtained from application of a fixed multiple logistic regression model, as an estimator of the number of potentially preventable nosocomial infections. RESULTS: The calculated number of patients with preventable infections was 7,493, which constituted 21.6% of the infected patients. Among hospital areas, intensive care had the lowest preventability rate (4.6%), whereas gynecology and obstetrics had the highest (40.6%). There was a significant inverse exposure-effect relationship between the proportion of preventable infections and the National Nosocomial Infections Surveillance (NNIS) System risk index. No correlation was observed between the prevalence of patients with nosocomial infection and the percentage of preventable infections. CONCLUSION: This analysis suggests that fewer nosocomial infections may be preventable in Spanish hospitals than previously assumed. 相似文献
96.
Zachary A Rodd Richard L Bell Ying Zhang James M Murphy Avram Goldstein Alejandro Zaffaroni Ting-Kai Li William J McBride 《Neuropsychopharmacology》2005,30(2):330-338
The meso-limbic dopamine (DA) system has an important role in regulating alcohol drinking. Previous findings from our laboratory indicated that Wistar rats self-administered ethanol (EtOH) directly into the posterior, but not anterior, ventral tegmental area (VTA), and that coadministration of a DA D(2,3) receptor agonist or a serotonin-3 (5-HT3) receptor antagonist blocked EtOH self-administration. In addition, we reported that alcohol-preferring (P) rats self-administered acetaldehyde (ACD), the first metabolite of EtOH, into the posterior VTA. The objectives of this study were to compare the reinforcing effects of EtOH and ACD within the VTA of P rats to examine the possibility that the reinforcing effects of EtOH within the VTA may be mediated by its conversion to ACD. Adult female P rats were stereotaxically implanted with guide cannulae aimed at either the posterior or anterior VTA. At 1 week after surgery, rats were placed in standard two-lever (active and inactive) experimental chambers for a total of seven to eight sessions. The 4-h sessions were conducted every other day. The results indicated that (a) 75-300 mg% (17-66 mM) EtOH and 6-90 microM ACD were self-administered into the posterior, but not anterior, VTA; (b) the self-administration of 150 mg% EtOH was not altered by coinfusion of a catalase inhibitor; (c) coadministration of the D(2/3) agonist quinpirole (100 microM) blocked the self-infusions of 150 mg% EtOH and 23 microM ACD into the posterior VTA; and (d) coadministration of 200 microM ICS205,930 (5-HT3 receptor antagonist) prevented the self-infusion of 150 mg% EtOH, whereas concentrations of ICS 205,930 up to 400 microM had no effect on the self-infusion of 23 microM ACD into the posterior VTA. Overall, the results of this study indicate that EtOH and ACD can independently produce reinforcing effects within the posterior VTA, and that activation of DA neurons mediates these effects. Furthermore, activation of 5-HT3 receptors within the posterior VTA is involved in the self-infusion of EtOH, but not ACD. 相似文献
97.
Induction of p53 up-regulated modulator of apoptosis messenger RNA by chemotherapeutic treatment of locally advanced breast cancer. 总被引:1,自引:0,他引:1
Rutger Middelburg Richard R de Haas Henk Dekker Ron M Kerkhoven Paula R Pohlmann Adolfo Fuentes-Alburo Alejandro Mohar Herbert M Pinedo Jan Lankelma 《Clinical cancer research》2005,11(5):1863-1869
PURPOSE: In biopsies of patients with locally advanced breast cancer, we investigated the in vivo changes of the gene expression pattern induced by chemotherapy to find genes that are potentially responsible for the efficacy of the drug. EXPERIMENTAL DESIGN: Early cellular responses to chemotherapy-induced damage, both in vivo and in vitro, were investigated by analyzing chemotherapy-induced changes in gene expression profiles. Core biopsies were taken from nine patients with locally advanced breast cancer, before and at 6 hours after initiation of doxorubicin-based chemotherapy. Both samples were cohybridized on the same microarray containing 18,000 cDNA spots. RESULTS: The analysis revealed marked differences in gene expression profile between treated and untreated samples. The gene which was most frequently found to be differentially expressed was p53 up-regulated modulator of apoptosis (PUMA). This gene was up-regulated in eight of nine patients with an average factor of 1.80 (range, 1.36-2.73). In vitro MCF-7 breast cancer cells exposed to clinically achievable doxorubicin concentrations for 6 hours revealed marked induction of PUMA mRNA, as well. CONCLUSIONS: This is the first report describing PUMA mRNA to be up-regulated as a response to chemotherapy in patients. Because PUMA is a known member of the family of BH3-only proapoptotic proteins, this finding suggests PUMA's potential importance for the response to anticancer drugs. 相似文献
98.
Angiogenesis in the bone marrow of patients with breast cancer. 总被引:3,自引:0,他引:3
Mariana Chavez-Macgregor Alejandro Aviles-Salas Dan Green Adolfo Fuentes-Alburo Celedonio Gómez-Ruiz Alvaro Aguayo 《Clinical cancer research》2005,11(15):5396-5400
PURPOSE: Pathologic angiogenesis has been correlated with tumor growth, dissemination, metastasis, and prognosis in solid tumors including breast cancer. Angiogenesis has also been implicated in the pathophysiology of, and shown to be a therapeutic target in tumors arising in the bone marrow. The status of angiogenesis in the bone marrow of breast cancer patients is unknown. The aim of this study was to estimate the extent of bone marrow angiogenesis in this subset of patients. EXPERIMENTAL DESIGN: We studied 42 women with breast cancer in whom a bone marrow biopsy was done. Bone marrow samples were sorted according to their infiltration status by breast cancer cells. In all bone marrow sections, blood vessels were highlighted by staining endothelial cells with an antibody directed against the CD34-related antigen. A hematopathologist blind to the status of infiltration of breast cancer did the bone marrow vessel count. RESULTS: Nineteen patients (45%) had bone marrow metastasis. The bone marrow microvessel density was significantly higher in patients with bone marrow metastases compared with patients without bone marrow metastases (P < 0.0005). Median bone marrow microvessel density was 2 for the negative bone marrow group, and 15 for the positive bone marrow group. An increased microvessel density was correlated with presence of disease at last follow-up. CONCLUSIONS: This is the first study showing that bone marrow microvessel density is significantly higher in breast cancer patients with bone marrow metastases, when compared with breast cancer patients without evidence of bone marrow metastatic disease. Further research is needed to shed light into the prognostic and therapeutic relevance of this finding. 相似文献
99.
Blanca Ramos-Cerrillo Alejandro Olvera George V Odell Fernando Zamudio Jorge Paniagua-Solís Alejandro Alagón Roberto P Stock 《Toxicon》2004,44(5):507-514
In this study we report the isolation and characterization of several sphingomyelinase D isoforms from the venoms of the North American spiders Loxosceles boneti and Loxosceles reclusa, from Mexico and the United States, respectively. We have measured their enzymatic activity, their capacity to induce necrotic lesions in rabbits, cloned the cDNAs coding for the mature forms of two of the isoforms from L. boneti and two of L. reclusa based on N-terminal sequence information of the purified proteins, and performed a comprehensive comparison of the sequence data generated by us with that reported for other sphingomyelinase genes to date. 相似文献
100.