Radiation is an important modality in cancer treatment, and eighty percent of cancer patients need radiotherapy at some point during their clinical management. However, radiation-induced damage to normal tissues restr...Radiation is an important modality in cancer treatment, and eighty percent of cancer patients need radiotherapy at some point during their clinical management. However, radiation-induced damage to normal tissues restricts the therapeutic doses of radiation that can be delivered to tumours and thereby limits the effectiveness of the treatment. The use of radioprotectors represents an obvious strategy to obtain better tumour control using a higher dose in radiotherapy. However, most of the synthetic radioprotective compounds studied have shown inadequate clinical efficacy owing to their inherent toxicity and high cost. Hence, the development of radioprotective agents with lower toxicity and an extended window of protection has attracted a great deal of attention, and the identification of alternative agents that are less toxic and highly effective is an absolute necessity. Recent studies have shown that alpha-2-macroglobulin（α2M） possesses radioprotective effects. α2M is a tetrameric, disulfide-rich plasma glycoprotein that functions as a nonselective inhibitor of different types of non-specific proteases and as a carrier of cytokines, growth factors, and hormones. α2M induces protein factors whose interplay underlies radioprotection, which supports the idea that α2M is the central effector of natural radioprotection in the rat. Pretreatment with α2M has also induced a significant reduction of irradiation-induced DNA damage and the complete restoration of liver and body weight. Mihailovi？ et al. concluded that the radioprotection provided by α2M was in part mediated through cytoprotection of new blood cells produced in the bone marrow; these authors also indicated that an important aspect of the radioprotective effect of amifostine was the result of the induction of the endogenous cytoprotective capability of α2M. The radioprotective effects of α2M are possibly due to antioxidant, antifibrosis, and anti-inflammatory functions, as well as the maintenance of homeostasis, and enhancement of the DNA repair and cell recovery processes. This review is the first to summarise the observations and elucidate the possible mechanisms responsible for the beneficial effects of α2M. The lacunae in the existing knowledge and directions for future research are also addressed.展开更多
AIM: To assess the effi cacy of peginterferon alpha 2b at doses of 50 μg weekly and 80 μg weekly (based on body weight) plus ribavirin in HCV genotype 2 and genotype 3 chronic hepatitis C patients. METHODS: During t...AIM: To assess the effi cacy of peginterferon alpha 2b at doses of 50 μg weekly and 80 μg weekly (based on body weight) plus ribavirin in HCV genotype 2 and genotype 3 chronic hepatitis C patients. METHODS: During the study period of Jan 2002 to Dec 2003, all patients diagnosed as chronic hepatitis C or HCV related compensated cirrhosis were treated with peginterferon alpha 2b 50 μg S/C weekly (body weight < 60 kg) or 80 μg S/C weekly (body weight > 60 kg) plus ribavirin 800 mg/d for 24 wk. RESULTS: Overall 28 patients, 14 patients in each group (based on body weight) were treated during the period. Out of 28 patients, 75% were genotype 3, 18% were genotype 2 and 7% were genotype 1. The mean dose of peginterferon alpha 2b was 0.91 μg/kg in group 1 and 1.23 μg/kg in group 2 respectively. The end of treatment and sustained virologic response rates were 82% and 78% respectively. Serious adverse effects were seen in 3.5% patients. CONCLUSION: Low dose peginterferon alpha 2b in combination with ribavirin for 24 wk is effective in HCV genotype 2 and 3 chronic hepatitis C patients.展开更多
基金supported by grant of the Science and Technology Planning Project of Guangdong Province (2010B060900052 and 2009B030801186)the Fundamental Research Funds for the Central Universities (the Young Teacher Training Project of Sun Yat-sen University 09ykpy12)the Medical Scientific Research Project of Zhuhai City (2012003)
文摘Radiation is an important modality in cancer treatment, and eighty percent of cancer patients need radiotherapy at some point during their clinical management. However, radiation-induced damage to normal tissues restricts the therapeutic doses of radiation that can be delivered to tumours and thereby limits the effectiveness of the treatment. The use of radioprotectors represents an obvious strategy to obtain better tumour control using a higher dose in radiotherapy. However, most of the synthetic radioprotective compounds studied have shown inadequate clinical efficacy owing to their inherent toxicity and high cost. Hence, the development of radioprotective agents with lower toxicity and an extended window of protection has attracted a great deal of attention, and the identification of alternative agents that are less toxic and highly effective is an absolute necessity. Recent studies have shown that alpha-2-macroglobulin（α2M） possesses radioprotective effects. α2M is a tetrameric, disulfide-rich plasma glycoprotein that functions as a nonselective inhibitor of different types of non-specific proteases and as a carrier of cytokines, growth factors, and hormones. α2M induces protein factors whose interplay underlies radioprotection, which supports the idea that α2M is the central effector of natural radioprotection in the rat. Pretreatment with α2M has also induced a significant reduction of irradiation-induced DNA damage and the complete restoration of liver and body weight. Mihailovi？ et al. concluded that the radioprotection provided by α2M was in part mediated through cytoprotection of new blood cells produced in the bone marrow; these authors also indicated that an important aspect of the radioprotective effect of amifostine was the result of the induction of the endogenous cytoprotective capability of α2M. The radioprotective effects of α2M are possibly due to antioxidant, antifibrosis, and anti-inflammatory functions, as well as the maintenance of homeostasis, and enhancement of the DNA repair and cell recovery processes. This review is the first to summarise the observations and elucidate the possible mechanisms responsible for the beneficial effects of α2M. The lacunae in the existing knowledge and directions for future research are also addressed.
文摘AIM: To assess the effi cacy of peginterferon alpha 2b at doses of 50 μg weekly and 80 μg weekly (based on body weight) plus ribavirin in HCV genotype 2 and genotype 3 chronic hepatitis C patients. METHODS: During the study period of Jan 2002 to Dec 2003, all patients diagnosed as chronic hepatitis C or HCV related compensated cirrhosis were treated with peginterferon alpha 2b 50 μg S/C weekly (body weight < 60 kg) or 80 μg S/C weekly (body weight > 60 kg) plus ribavirin 800 mg/d for 24 wk. RESULTS: Overall 28 patients, 14 patients in each group (based on body weight) were treated during the period. Out of 28 patients, 75% were genotype 3, 18% were genotype 2 and 7% were genotype 1. The mean dose of peginterferon alpha 2b was 0.91 μg/kg in group 1 and 1.23 μg/kg in group 2 respectively. The end of treatment and sustained virologic response rates were 82% and 78% respectively. Serious adverse effects were seen in 3.5% patients. CONCLUSION: Low dose peginterferon alpha 2b in combination with ribavirin for 24 wk is effective in HCV genotype 2 and 3 chronic hepatitis C patients.
