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Survival Levels (survival + level)
Selected AbstractsPrediction of poor survival by cyclooxygenase-2 in patients with T4 nasopharyngeal cancer treated by radiation therapy: Clinical and in vitro studiesHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 6 2005Wen-Cheng Chen MD Abstract Background. This study was undertaken to determine the status of cyclooxygenase-2 (COX-2) in nasopharyngeal cancer (NPC) in Taiwanese patients and its relationship to survival after radiotherapy (RT). In addition, the effect of NS-398, a potent selective COX-2 inhibitor, was tested in vitro alone and in combination with radiation on NPC-BM1 human NPC cells as a prelude to using this drug along with RT in the treatment of patients with NPC. Methods. Thirty-seven patients diagnosed with T4N0,3M0 NPC were enrolled into this study. COX-2 expression was determined by immunohistochemical staining of formalin-fixed, paraffin-embedded tumor tissue. Patient survival was the clinical end point. The effects of COX-2 expression on cell survival and radioresistance was tested in vitro using the selective COX-2 inhibitor NS-398 in conjunction with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazonium bromide (MTT) and clonogenic assays. Results. COX-2 immunoreactivity was detected in 62% of NPC tumors, and expression levels were high in 43%. Survival analysis showed the 5-year overall survival rates for patients who had high COX-2 expression was 27% compared with 60% for those with low/absent expression (p = .047). Pattern of failure analysis showed no significant difference between high and low COX-2 expression in locoregional failure (27% vs 25%, p = .91). However, patients with N0 to N1 disease and high COX-2 expression had a significantly higher incidence of distant metastasis compared with patients with stage N0 to N1 disease and low COX-2 expression (83% vs 15%, p = .004). This difference was not observed in patients with N2 to N3 disease. This difference contributed to worse survival of patients whose tumors had high COX-2 expression levels. The selective COX-2 inhibitor NS-398 was directly cytotoxic to NPC-BM1 cells in vitro, as judged in an MTT assay (viable cells decreased from 92% to 76%, 52%, and 22%, with increases of NS-398 from 20 to 40, 60, and 80 ,M, respectively). Radiation-induced cell death was also increased by treatment with NS-398. At a 10% survival level, 40 ,M NS-398 increased radiation cytotoxicity by a factor of 1.37, whereas 60 ,M increased it by a factor of 4.9. Conclusions. COX-2 overexpression is a predictor for poor survival for advanced stage NPC. In vitro, NS-398 radiosensitizes the NPC-BM1 cell line, providing a basis for testing the combination of COX-2 inhibitors with radiation in the treatment of patients with NPC. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source] Resin-bonded fixed partial denture retention: a retrospective 13-year follow-upJOURNAL OF ORAL REHABILITATION, Issue 10 2003M. Zalkind summary, A total of 51 resin-bonded fixed partial dentures (RBFPDs) were inserted under controlled clinical conditions and evaluated over a period of 13 years. Three levels of survival were defined: complete survival (no debonding); functional survival (loss of retention on one occasion with rebonding of the original RBFPD); and multiple survival (loss of retention on several occasions with rebonding of the original RBFPD). The effect of the aetiology, location (anterior/posterior or maxillary/mandibulary) and number of units of the missing tooth on RBFPD survival rates were investigated. The mean survival times and confidence levels were determined for each survival category, using the Kaplan,Meier procedure. The relative risks were calculated by the Cox regression procedure. The overall complete survival level of the study population at the end of the follow-up period was 85 months ± 13%. Rebonding the RBFPDs once increased the overall functional survival rate to 112 months ± 10% and multiple rebonding led to a further increase to 131 months ± 8%. The RBFPD placement under conditions of good periodontal support in which orthodontic treatment was not required, such as trauma among other factors, showed significantly higher survival rates than those placed after periodontal or orthodontic treatment. This indicates that, under both these conditions, RBFPDs may serve as long-term or semi-permanent restorations. [source] ACID TOLERANCE OF ESCHERICHIA COLI FOLLOWING COLD SHOCK TREATMENTJOURNAL OF FOOD SAFETY, Issue 2 2003GREG BLANK ABSTRACT The effect of an initial cold shock treatment (2 h at 10C), following an abrupt downshift in temperature from 37 to 10C, on the subsequent growth and survival of Escherichia coli strains O157:H7 and MY20 (Biotype 1) in acidified Trypticase soy broth (TSB) and fruit juices (orange, apple) was investigated. Overall, no difference in growth at 37C was observed between each cold shocked and noncold shocked E. coli strain when cultured in TSB adjusted with either acetic acid (pH 6.0)or malic, citric and tartaric acid (each adjusted to: pH 4.5, 5.0, 5.5, 6.0). However, significant (P ± 0.05) differences in survival were observed between cold shocked and noncold shocked populations in TSB acidified with acetic acid (pH 5.0) or citric, malic and tartaric acid (pH 4.0). For strain MY20, survivor levels for cold shocked cells in TSB acidified with acetic acid citric, malic and tartaric acid at 8C were significantly (P ± 0.05) higher than in noncold shocked populations. Also, at 37C survival levels for cold shocked cells were significantly (P ± 0.05) higher than noncold shocked cells in TSB acidified with either malic or tartaric acid (pH 4.0). For the O157:H7 strain, survivor levels were higher (P ± 0.05) for cold shocked cells when maintained in TSB at 37C regardless of acid type. At 8C, cold shock treatment only increased (P ± 0.05) the survival of the O157:H7 strain in TSB adjusted with acetic acid (pH 6.0). Acid cross protection induced by cold shocking, as evidenced by enhanced survival, was not apparent for either E. coil strain in apple (pH 3.5) or orange juice (pH 3.8) maintained at 8C. [source] Microbial Inactivation Kinetics during High-Pressure Carbon Dioxide Treatment: Nonlinear Model for the Combined Effect of Temperature and Pressure in Apple JuiceJOURNAL OF FOOD SCIENCE, Issue 8 2008G. Ferrentino ABSTRACT:, Isobaric and isothermal semi-logarithmic survival curves of natural microflora in apple juice treated with high-pressure carbon dioxide at 7, 13, and 16 MPa pressures and 35, 50, and 60 °C temperatures were fitted with a nonlinear equation to find the values of the coefficient b(P ), b(T ), n(P ), and n(T ). Profiles of the model parameters were obtained as a function of pressure and temperature. The model fitted with good agreement (R2 > 0.945), the survival curves. An empirical equation was proposed to describe the combined effects of pressure and temperature. The equation, derived from a power law model, was written in the form: . The proposed model fitted the experimental data well. At 7 MPa and 50 and 60 °C, 13 MPa and 35 and 60 °C, 16 MPa and 35 °C, the model provided log10 reduction residual values (observed value , fitted value) lower than 0.284 showing a good agreement between the experimental and the predicted survival levels. [source] The effect of different carbon sources on the nutritional value of bioflocs, a feed for Macrobrachium rosenbergii postlarvaeAQUACULTURE RESEARCH, Issue 4 2010Roselien Crab Abstract A 15-day lab-scale experiment was performed to determine the possible use of bioflocs as a feed for Macrobrachium rosenbergii postlarvae. The bioflocs were grown on acetate, glycerol and glucose. A glycerol-fed reactor was initially inoculated with a Bacillus spores mixture. The highest protein content was obtained in the (glycerol+Bacillus) bioflocs, i.e. 58±9% dry weight (DW). The glycerol and acetate bioflocs showed a lower, but similar content (42,43% DW) and glucose bioflocs contained 28±3% DW. Higher total n-6 fatty acid contents were observed in the glycerol and (glycerol+Bacillus) bioflocs. The vitamin C content was variable, up to 54 ,g ascorbic acid g,1 DW in the glycerol bioflocs. Bioflocs were fed to M. rosenbergii postlarvae as the sole feed. High survival levels were obtained in the (glycerol+Bacillus) and glucose groups, i.e. 75±7% and 70±0% respectively. This was significantly higher than the starvation control (0% survival after 15 days). This indicated that the prawns were able to feed on the bioflocs. These results are in accordance with the biofloc's nutritional parameters and suggest that the choice of the carbon source used for growing bioflocs is of prime importance. [source] | |||||||||||||