Prostate-specific antigen （PSA） testing for the early diagnosis of prostate cancer has led to a decrease in cancer mortality. However, the high prevalence of low-grade prostate cancer and its long natural history, c...Prostate-specific antigen （PSA） testing for the early diagnosis of prostate cancer has led to a decrease in cancer mortality. However, the high prevalence of low-grade prostate cancer and its long natural history, competing causes of death in older men and treatment patterns of prostate cancer, have led to dramatic overtreatment of the disease. Improved markers of prostate cancer lethality are needed to reduce the overtreatment of prostate cancer that leads to a reduced quality of life without extending life for a high proportion of men. The PSA level prior to treatment is routinely used in multivariable models to predict prostate cancer aggressiveness. PSA isoforms and PSA kinetics have been associated with more aggressive phenotypes, but are not routinely employed as part of prediction tools prior to treatment. PSA kinetics is a valuable marker of lethality post treatment and routinely used in determininE the need for salva=e theraov.展开更多
Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still...Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still remains unclear.Herein,the oxidation behavior and mechanisms of PSA resin are systematically investigated combining kinetic analysis and Reax FF molecular dynamics(MD)simulations.Thermogravimetric analysis indicates that the oxidation process of PSA resin undergoes two main steps:oxidative mass gain and oxidative degradation.The distributed activation energy model(DAEM)is employed for describing oxidation processes and the best-fit one is obtained using genetic algorithms and differential evolution.DAEM model demonstrates that the oxidative weight gain stage is dominated by two virtual reactants and the oxidative degradation stage consists of three virtual reactants.Correspondingly,the observation of MD reaction pathways indicates that oxygen oxidation of unsaturated structures occurs in the initial stage,which results in the formation of PSA resin oxides.Furthermore,cracked pieces react with O_(2)to generate CO and other chemicals in the second step.The resin matrix's great antioxidation resilience is illustrated by the formation of SiO_(2).The analysis based on MD simulations exhibits an efficient computational proof with the experiments and DAEM methods.Based on the results,a two-stage reaction mechanism is proposed,which provides important theoretical support for the subsequent study of the oxidation behavior of silica-based resins.展开更多
In the targeted therapy era, it is critical to know the certain points to start or discontinue chemotherapy for patients with castration resistant metastatic prostate cancer. The prognostic factors to determine this r...In the targeted therapy era, it is critical to know the certain points to start or discontinue chemotherapy for patients with castration resistant metastatic prostate cancer. The prognostic factors to determine this response are still not clear yet. We tried to find out if the PSA doubling time helps us to predict the patients who will benefit from docetaxel chemotherapy most, and also to question the value of the PSA response to chemotherapy. Retrospectively, 70 patients who had hormone refractory metastatic prostate cancer that were given at least 4 cycles of docetaxel chemotherapy between 2002 and 2015 were evaluated. After the onset of docetaxel, PSA response to therapy and overall survival rates were analyzed to figure out if these parameters were related to PSA doubling time. The only statistically significant prognostic parameter affecting overall survival was the best PSA response rate to docetaxel chemotherapy being over or under 50%. The most significant parameter that affects the PSA doubling time was the clinical stage at the time of diagnosis. PSA doubling time is not a useful predictive tool for predicting response to docetaxel. By means of overall survival, the clinical stage at the time of diagnosis was the best predictive tool for our cohort. The best PSA response rate to docetaxel chemotherapy was found to be a valuable parameter. The study being retrospective and the low number of patients included in this cohort can be the main weaknesses of this study. Further studies to determine which other factors can be useful are needed.展开更多
Background:?We aim to estimate prostate-specific antigen (PSA) half-life after salvage radiation therapy (SRT) in patients with detectable PSA after radical prostatectomy (RP). Methods: A total of 272 patients treated...Background:?We aim to estimate prostate-specific antigen (PSA) half-life after salvage radiation therapy (SRT) in patients with detectable PSA after radical prostatectomy (RP). Methods: A total of 272 patients treated with salvage radiotherapy between July 1987 and July 2010 were included in this IRB approved retrospective analysis. The median pre-salvage radiotherapy dose was 0.6 ng/mL (range, 0.2 - 21.9 ng/mL), 47 patients had at least a minimum tumor stage of T3b, 29 had a Gleason score over 7, and median dose was 66.6 Gy (range, 54.0 - 72.4 Gy). Results: The estimated PSA half-life in our cohort of patients was 3.0 months (95% CI, 2.9 - 3.2 months;range, 0.5 - 28.5 months). There was no evidence of a statistically significant association between PSA half-life and any baseline clinicopathologic characteristics. The median interval between individual PSA measurements was noted to be 4.6 months (range, 0.1 - 20.4 months). The median interval from the start of radiation therapy to the nadir PSA was 6.3 months (range, 1.3 - 79.1 months). PSA half-life remained approximately 3.0 months when accounting for infrequent and outlier PSA values. Conclusion: The PSA half-life after definitive RT has been reported to be approximately 1.6 months. Our analysis found the PSA half-life after SRT to be approximately twice that of patients treated with definitive RT. These results provide useful information to radiation oncologists when counseling patients both before and after SRT regarding expectations about PSA measurements.展开更多
文摘Prostate-specific antigen （PSA） testing for the early diagnosis of prostate cancer has led to a decrease in cancer mortality. However, the high prevalence of low-grade prostate cancer and its long natural history, competing causes of death in older men and treatment patterns of prostate cancer, have led to dramatic overtreatment of the disease. Improved markers of prostate cancer lethality are needed to reduce the overtreatment of prostate cancer that leads to a reduced quality of life without extending life for a high proportion of men. The PSA level prior to treatment is routinely used in multivariable models to predict prostate cancer aggressiveness. PSA isoforms and PSA kinetics have been associated with more aggressive phenotypes, but are not routinely employed as part of prediction tools prior to treatment. PSA kinetics is a valuable marker of lethality post treatment and routinely used in determininE the need for salva=e theraov.
基金financially supported by National Natural Science Foundation of China(22008073,22078100,21878091)Shanghai Sailing Program(20YF1410600)。
文摘Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still remains unclear.Herein,the oxidation behavior and mechanisms of PSA resin are systematically investigated combining kinetic analysis and Reax FF molecular dynamics(MD)simulations.Thermogravimetric analysis indicates that the oxidation process of PSA resin undergoes two main steps:oxidative mass gain and oxidative degradation.The distributed activation energy model(DAEM)is employed for describing oxidation processes and the best-fit one is obtained using genetic algorithms and differential evolution.DAEM model demonstrates that the oxidative weight gain stage is dominated by two virtual reactants and the oxidative degradation stage consists of three virtual reactants.Correspondingly,the observation of MD reaction pathways indicates that oxygen oxidation of unsaturated structures occurs in the initial stage,which results in the formation of PSA resin oxides.Furthermore,cracked pieces react with O_(2)to generate CO and other chemicals in the second step.The resin matrix's great antioxidation resilience is illustrated by the formation of SiO_(2).The analysis based on MD simulations exhibits an efficient computational proof with the experiments and DAEM methods.Based on the results,a two-stage reaction mechanism is proposed,which provides important theoretical support for the subsequent study of the oxidation behavior of silica-based resins.
文摘In the targeted therapy era, it is critical to know the certain points to start or discontinue chemotherapy for patients with castration resistant metastatic prostate cancer. The prognostic factors to determine this response are still not clear yet. We tried to find out if the PSA doubling time helps us to predict the patients who will benefit from docetaxel chemotherapy most, and also to question the value of the PSA response to chemotherapy. Retrospectively, 70 patients who had hormone refractory metastatic prostate cancer that were given at least 4 cycles of docetaxel chemotherapy between 2002 and 2015 were evaluated. After the onset of docetaxel, PSA response to therapy and overall survival rates were analyzed to figure out if these parameters were related to PSA doubling time. The only statistically significant prognostic parameter affecting overall survival was the best PSA response rate to docetaxel chemotherapy being over or under 50%. The most significant parameter that affects the PSA doubling time was the clinical stage at the time of diagnosis. PSA doubling time is not a useful predictive tool for predicting response to docetaxel. By means of overall survival, the clinical stage at the time of diagnosis was the best predictive tool for our cohort. The best PSA response rate to docetaxel chemotherapy was found to be a valuable parameter. The study being retrospective and the low number of patients included in this cohort can be the main weaknesses of this study. Further studies to determine which other factors can be useful are needed.
文摘Background:?We aim to estimate prostate-specific antigen (PSA) half-life after salvage radiation therapy (SRT) in patients with detectable PSA after radical prostatectomy (RP). Methods: A total of 272 patients treated with salvage radiotherapy between July 1987 and July 2010 were included in this IRB approved retrospective analysis. The median pre-salvage radiotherapy dose was 0.6 ng/mL (range, 0.2 - 21.9 ng/mL), 47 patients had at least a minimum tumor stage of T3b, 29 had a Gleason score over 7, and median dose was 66.6 Gy (range, 54.0 - 72.4 Gy). Results: The estimated PSA half-life in our cohort of patients was 3.0 months (95% CI, 2.9 - 3.2 months;range, 0.5 - 28.5 months). There was no evidence of a statistically significant association between PSA half-life and any baseline clinicopathologic characteristics. The median interval between individual PSA measurements was noted to be 4.6 months (range, 0.1 - 20.4 months). The median interval from the start of radiation therapy to the nadir PSA was 6.3 months (range, 1.3 - 79.1 months). PSA half-life remained approximately 3.0 months when accounting for infrequent and outlier PSA values. Conclusion: The PSA half-life after definitive RT has been reported to be approximately 1.6 months. Our analysis found the PSA half-life after SRT to be approximately twice that of patients treated with definitive RT. These results provide useful information to radiation oncologists when counseling patients both before and after SRT regarding expectations about PSA measurements.
