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71.
Carlos Santamaría Silda Larios Yamileth Angulo Javier Pizarro-Cerda Jean-Pierre Gorvel Edgardo Moreno Bruno Lomonte 《Toxicon》2005,45(7):807-815
A short peptide derived from the C-terminal region of Bothrops asper myotoxin II, a Lys49 phospholipase A(2) (PLA(2)), was previously found to reproduce the bactericidal activity of its parent molecule. In this study, a panel of eight PLA(2) myotoxins purified from crotalid snake venoms, including both Lys49 and Asp49-type isoforms, were all found to express bactericidal activity, indicating that this may be a common action of the group IIA PLA(2) protein family. A series of 10 synthetic peptide variants, based on the original C-terminal sequence 115-129 of myotoxin II and its triple Tyr-->Trp substituted peptide p115-W3, were characterized. In vitro assays for bactericidal, cytolytic and anti-endotoxic activities of these peptides suggest a general correlation between the number of tryptophan substitutions introduced and microbicidal potency, both against Gram-negative (Salmonella typhimurium) and Gram-positive (Staphylococcus aureus) bacteria. Peptide variants with high bactericidal activity also tended to be more cytolytic towards skeletal muscle C2C12 myoblasts, thus limiting their potential in vivo use. However, the peptide variant pEM-2 (KKWRWWLKALAKK) showed reduced toxicity towards muscle cells, while retaining high bactericidal potency. This peptide also showed the highest endotoxin-neutralizing activity in vitro, and was shown to functionally interact with lipopolysaccharide (LPS) using a chimeric bacteria model. The bactericidal and anti-endotoxic properties of pEM-2, combined with its relatively low toxicity towards eukaryotic cells, highlight it as a promising candidate for further evaluation of its antimicrobial potential in vivo. 相似文献
72.
BACKGROUND AND PURPOSE: To determine whether the information gathered from a fixed number of periodic verification films accurately reflects the true imprecision in patient positioning during the whole radiation therapy of early breast cancer. PATIENTS AND METHODS: A total of 204 medial and lateral treatment fields were evaluated in 102 breast cancer patients treated with conservative surgery and radiation therapy. For each treatment field, the central lung distance was measured on portal films obtained from one simulation and four treatment controls at weekly intervals during breast irradiation. Systematic and random errors in patient positioning throughout all treatment fractions were estimated from the available controls using Bayesian methods. RESULTS: The average systematic and random errors during treatment controls were 2.7 and 1.9 mm, respectively. For these mean control values, the probabilities that the true systematic and random errors remain below 5mm during all treatment fractions were 99 and 100%, respectively. CONCLUSIONS: Reproducibility of patient positioning was supported by a virtually null probability for systematic or random errors greater than 5 mm during the whole radiation therapy. Weekly verification films seem to be sufficient to estimate patient positioning errors with high accuracy in radiotherapy of early breast cancer. 相似文献
73.
Javier Sastre Eugenio Marcuello Bartomeu Masutti Matilde Navarro Silvia Gil Antonio Antón Albert Abad Enrique Aranda Joan Maurel Manuel Valladares Inmaculada Maestu Alfredo Carrato José María Vicent Eduardo Díaz-Rubio 《Journal of clinical oncology》2005,23(15):3545-3551
PURPOSE: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients. PATIENTS AND METHODS: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion. RESULTS: By intent-to-treat analysis, in 85 assessable patients, the objective response rate was 35% (95% CI, 25% to 46%), and stable disease was 33% (95% CI, 23% to 44%). Median time to progression was 8.0 months (95% CI, 6.0 to 10.0 months), and median overall survival time was 15.3 months (95% CI, 13.8 to 16.9 months). Toxicity was moderate. Grade 3 and 4 neutropenia, diarrhea, and asthenia were observed in 21%, 17%, and 13% of patients, respectively. Only one case of neutropenic fever occurred. There were two toxic deaths, one was a result of grade 4 diarrhea and acute kidney failure, and the other was a result of massive intestinal hemorrhage in the first cycle. The study of prognostic factors did not reveal any predictive factor of response. Response to treatment and baseline lactate dehydrogenase were the main factors conditioning progression-free and overall survival. CONCLUSION: Twice a month continuous-infusion CPT-11 combined with FU is a valid therapeutic alternative for elderly patients in good general condition. 相似文献
74.
Vicente Valentín Maganto Carlos Camps Herrero Joan Carulla Torrent Javier Cassinello Espinosa Javier Dorta Delgado Carlos Jara Sánchez José Andrés Moreno Nogueira 《Clinical & translational oncology》2005,7(5):205-212
INTRODUCTION: Oral trans-mucosal fentanyl citrate (OTFC) is the one drug specifically developed for the management of breakthrough pain. This study assesses the long-term safety and efficacy of OTFC standard clinical conditions. Patients and methods. Six-month observational study performed on cancer patients with episodes of breakthrough pain. Safety was assessed by recording the advent of adverse events and efficacy by the evaluating the intensity of breakthrough pain. RESULTS: 174 cancer patients were recruited into the study. All adverse reactions reported were mild or moderate. OTFC was significantly faster (time to the commencement of pain relief: 12.7 +/- 11.4 vs 32.7 +/- 18.4 minutes; p < 0.001) and potent (post-treatment pain intensity: 3.4 +/- 1.5 vs 4.3 +/- 1.5; p < 0.001) than the previously-used drugs. CONCLUSIONS: This observational study confirms the good safety profile of OTFC as well as its effectiveness over long-term period treatment of breakthrough pain. 相似文献
75.
Fernando Moreno Antón Javier Sastre Valera Belén Loboff de León Sara López-Tarruella Luis Ortega Medina Eduardo Díaz-Rubio 《Clinical & translational oncology》2005,7(7):321-323
Metastastic tumours involving the epididymis are rare and most often found in patients with disseminated disease. It is even more unusual when the metastasis of the epididymis is the first sign of tumour recurrence. We report a case of an asymptomatic recurrent colon carcinoma presenting as metastasis in the epididymis. Although metastatic cancer presenting as an intra-scrotal mass is extremely rare, it should be considered as a possibility in patients who present with a mass involving the testicle or epididymis. 相似文献
76.
Immunohistochemical expression of DNA repair proteins in familial breast cancer differentiate BRCA2-associated tumors. 总被引:2,自引:0,他引:2
Emiliano Honrado Ana Osorio José Palacios Roger L Milne Lydia Sánchez Orland Díez Alicia Cazorla Kirsi Syrjakoski David Huntsman P?ivi Heikkil? Enrique Lerma Anne Kallioniemi Carmen Rivas William D Foulkes Heli Nevanlinna Javier Benítez 《Journal of clinical oncology》2005,23(30):7503-7511
PURPOSE: Morphologic and immunohistochemical studies of familial breast cancers have identified specific characteristics associated with BRCA1 mutation-associated tumors when compared with BRCA2 and non-BRCA1/2 tumors, but have not identified differences between BRCA2 and non-BRCA1/2 tumors. Because BRCA1 and BRCA2 genes participate in the DNA repair pathway, we have performed an immunohistochemical study with markers related to this pathway to establish the profile of the three groups. MATERIALS AND METHODS: We have studied two tissue microarrays that include 103 familial and 104 sporadic breast tumors, with a panel of DNA repair markers including ATM, CHEK2, RAD51, RAD50, XRCC3, and proliferating cell nuclear antigen. RESULTS: We found more frequent expression of CHEK2 in BRCA1 and BRCA2 tumors than in non-BRCA1/2 and sporadic tumors. We found absence of nuclear expression and presence of cytoplasmic expression of RAD51 in BRCA2 tumors that differentiate them from other familial tumors. We validated these results with a new series of patient cases. The final study with 253 familial patient cases (74 BRCA1, 71 BRCA2, 108 non-BRCA1/2), and 288 sporadic patient cases, has allowed us to confirm our preliminary results. Because BRCA2 tumors present a specific immunohistochemical profile for RAD51 and CHEK2 markers that is different from non-BRCA1/2 tumors, we have built a multivariate model with these markers that distinguish both tumors with an estimated probability of at least 76%. CONCLUSION: Our results suggest that BRCA2 tumors demonstrate more cytoplasmic and less nuclear RAD51 staining, and increased CHEK2 staining. This pattern may distinguish BRCA2 from familial non-BRCA1/2 tumors. 相似文献
77.
Dolores Caballero Jose A García-Marco Rodrigo Martino Victoria Mateos José M Ribera José Sarrá Angel León Guillermo Sanz Javier de la Serna Rafael Cabrera Marcos González Jorge Sierra Jesús San Miguel 《Clinical cancer research》2005,11(21):7757-7763
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
78.
Olmos M Vidarte MA Ballester JA Lasuen J Escobar A 《Revista espa?ola de anestesiología y reanimación》2000,47(8):337-342
OBJECTIVES: To assess the effect of a single prophylactic dose of urapidil for arterial hypertension during the period before start of extracorporeal circulation. PATIENTS AND METHODS: Forty-four patients with good ventricular function (ejection fraction < 40%) scheduled for coronary surgery were enrolled for prospective study. The patients were randomly assigned to receive 0.5 mg/kg of urapidil (group U, n = 22) or nothing (group N, n = 22) 3 min before skin incision. If hypertension developed sodium nitroprusside was administered, starting with a dose of 0.5 microgram/kg/min. Monitoring of arterial pressure, heart rate and ST segment (DII and V5) was continuous. The study ended with cannulation of the aorta. RESULTS: The demographic features, cardiovascular history, medication and duration of surgery were comparable in the two groups. Six patients in group U (27%) and 19 in group N (86%) developed arterial hypertension (p < 0.001), the duration of which was 2.23 +/- 4.49 min in group U and 9.64 +/- 9.7 min in group N (p < 0.05). Arterial hypotension was observed in 13 group U patients and 7 group N patients (NS). No significant differences in duration of tachycardia, bradycardia or myocardial ischemia were found. CONCLUSIONS: The administration of a single dose of urapidil prevents arterial hypertension during the phase before extracorporeal circulation for coronary surgery and reduces the need for nitroprusside. No clinically relevant side effects are evident. 相似文献
79.
80.
Jos Rubn Herrera-Atoche Nieves Aime Huerta-García Mauricio Escoffi-Ramírez Fernando Javier Aguilar-Prez Fernando Javier Aguilar-Ayala Eduardo Andrs Lizarraga-Colom Gabriel Eduardo Colom-Ruiz Ivn Daniel Zúiga-Herrera 《Medicine》2022,101(31)
This study’s objective was to compare the total and outside the cleft prevalence of dental anomalies (DA) between patients with cleft lip and palate (CLP) and a control group. This retrospective cross-sectional study was done under a case–control design. The case group consisted of 192 non-syndromic patients with complete CLP, while the control group included 411 patients. All subjects had orthopantomography, intra, and extraoral photographs. The prevalence of dental agenesis, supernumerary teeth, impacted teeth, dental transposition, and microdontia were compared using a chi-squared test (P < .05). Next, a second test was made, but only the anomalies outside the cleft were considered for this study. Total prevalence was 89.1% for cases, and 20.9% for controls (P < .01). The prevalence of each DA was significantly higher for the case group. In the analysis of DAs outside the cleft, the total prevalence was still significantly associated (P < .01); however, only dental agenesis was statistically significant (P < .01). Further analysis found that a high rate of upper premolar absence (P < .01) could explain this event. Patients with CLP have a higher prevalence of DAs compared to controls. After considering only the DAs outside the cleft, the total prevalence remains significantly higher. However, this phenomenon is explained mainly by the elevated prevalence of upper premolars’ agenesis. This study’s results suggest that environmental factors are behind the high prevalence of DAs in subjects with CLP. 相似文献