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
BACKGROUND The intricate relationship between type 2 diabetes mellitus(T2DM)and diabetic nephropathy(DN)presents a challenge in understanding the significance of various biomarkers in diagnosis.AIM To elucidate the ro...BACKGROUND The intricate relationship between type 2 diabetes mellitus(T2DM)and diabetic nephropathy(DN)presents a challenge in understanding the significance of various biomarkers in diagnosis.AIM To elucidate the roles and diagnostic values ofα2-macroglobulin(α2-MG),podocalyxin(PCX),α-L-fucosidase(AFU),retinol-binding protein-4(RBP-4),and cystatin C(CysC)in DN.METHODS From December 2018 to December 2020,203 T2DM patients were enrolled in the study.Of these,115 were diagnosed with DN(115 patients),while the remaining 88 patients were classified as non-DN.The urinary levels ofα2-MG,PCX,and AFU and the serum concentrations RBP-4 and CysC were measured in conjunction with other relevant clinical indicators to evaluate their potential correlations and diagnostic utility.RESULTS After adjustments for age and gender,significant positive correlations were observed between the biomarkers CysC,RBP-4,α2-MG/urinary creatinine(UCr),PCX/UCr,and AFU/UCr,and clinical indicators such as urinary albumin-to-creatinine ratio(UACR),serum creatinine,urea,24-h total urine protein,and neutrophil-to-lymphocyte ratio(NLR).Conversely,these biomarkers exhibited negative correlations with the estimated glomerular filtration rate(P<0.05).Receiver operating characteristic(ROC)curve analysis further demonstrated the diagnostic performance of these biomarkers,with UACR showcasing the highest area under the ROC curve(AUC^(ROC))at 0.97.CONCLUSION This study underscores the diagnostic significance ofα2-MG,PCX,and AFU in the development of DN.The biomarkers RBP-4,CysC,PCX,AFU,andα2-MG provide promising diagnostic insights,while UACR is the most potent diagnostic biomarker in assessing DN.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
AIM: To evaluate the response to pegylated-interferon alpha 2a in chronic hepatitis C patients on chronic haemodialysis. METHODS: Ten patients with chronic C hepatitis were enrolled in this study. All had increased ...AIM: To evaluate the response to pegylated-interferon alpha 2a in chronic hepatitis C patients on chronic haemodialysis. METHODS: Ten patients with chronic C hepatitis were enrolled in this study. All had increased aminotransferases for more than 6 too, positive antiHCV antibodies and positive PCR HCV-RNA. We administrated Peg-Interferon alpha 2a 180 μg/wk for 48 wk. After 12 wk of treatment we evaluated the biochemical and early virological response (EVR). At the end of the treatment we evaluated the biochemical response and 24 wk after the end of the treatment we evaluated the sustained virological response (SVR). We monitored the sideeffects during the treatment. RESULTS: Two patients dropped out in the first 12 wk of treatment and 2 after the first 12 wk of treatment. After 12 wk of treatment, 7 out of 8 patients had biochemical response and EVR and 1 had biochemical response but persistent viremia. We had to reduce the dose of pegylated-interferon to 135 μg/wk in 2 cases. Three out of 6 (50%) patients had SVR 24 wk after the end of the treatment. Intention-to-treat analysis showed that 3 out of 10 patients (30%) had SVR. Side-effects occurred in most of the patients (flu-like syndrome, thrombocytopenia or leucopoenia), but they did not impose the discontinuation of treatment. CONCLUSION: After 12 wk of treatment with Peg-Interferon alpha 2a (40 ku) in patients on chronic haemodialysis with chronic C hepatitis, EVR was obtained in 87.5% (7/8) of the cases. SVR was achieved in 50% of the cases (3/6 patients) that finished the 48 wk of treatment.展开更多
The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to...The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to a true strain of 0.70 in the temperature range of 750-950°C and strain rate range of 0.001-10 s-1.The corresponding microstructures were observed by means of the metallurgical microscopy and scanning electron microscopy(SEM).It was found that all cavities occurred at the bulge regions of the compression specimens.Most of cavities nucleated along prior beta boundaries oriented 45°to the compression axis,while others nucleated at the interfaces of lamellar alpha colonies.Cavity nucleation was inhibited with increasing the volume fraction of beta phase and the volume fraction spheroidized of lamellar alpha phase.展开更多
Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor corte...Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these 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.
基金pported by the Natural Science Foundation of Inner Mongolia Autonomous Region,No.2022MS08057.
文摘BACKGROUND The intricate relationship between type 2 diabetes mellitus(T2DM)and diabetic nephropathy(DN)presents a challenge in understanding the significance of various biomarkers in diagnosis.AIM To elucidate the roles and diagnostic values ofα2-macroglobulin(α2-MG),podocalyxin(PCX),α-L-fucosidase(AFU),retinol-binding protein-4(RBP-4),and cystatin C(CysC)in DN.METHODS From December 2018 to December 2020,203 T2DM patients were enrolled in the study.Of these,115 were diagnosed with DN(115 patients),while the remaining 88 patients were classified as non-DN.The urinary levels ofα2-MG,PCX,and AFU and the serum concentrations RBP-4 and CysC were measured in conjunction with other relevant clinical indicators to evaluate their potential correlations and diagnostic utility.RESULTS After adjustments for age and gender,significant positive correlations were observed between the biomarkers CysC,RBP-4,α2-MG/urinary creatinine(UCr),PCX/UCr,and AFU/UCr,and clinical indicators such as urinary albumin-to-creatinine ratio(UACR),serum creatinine,urea,24-h total urine protein,and neutrophil-to-lymphocyte ratio(NLR).Conversely,these biomarkers exhibited negative correlations with the estimated glomerular filtration rate(P<0.05).Receiver operating characteristic(ROC)curve analysis further demonstrated the diagnostic performance of these biomarkers,with UACR showcasing the highest area under the ROC curve(AUC^(ROC))at 0.97.CONCLUSION This study underscores the diagnostic significance ofα2-MG,PCX,and AFU in the development of DN.The biomarkers RBP-4,CysC,PCX,AFU,andα2-MG provide promising diagnostic insights,while UACR is the most potent diagnostic biomarker in assessing DN.
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.
文摘AIM: To evaluate the response to pegylated-interferon alpha 2a in chronic hepatitis C patients on chronic haemodialysis. METHODS: Ten patients with chronic C hepatitis were enrolled in this study. All had increased aminotransferases for more than 6 too, positive antiHCV antibodies and positive PCR HCV-RNA. We administrated Peg-Interferon alpha 2a 180 μg/wk for 48 wk. After 12 wk of treatment we evaluated the biochemical and early virological response (EVR). At the end of the treatment we evaluated the biochemical response and 24 wk after the end of the treatment we evaluated the sustained virological response (SVR). We monitored the sideeffects during the treatment. RESULTS: Two patients dropped out in the first 12 wk of treatment and 2 after the first 12 wk of treatment. After 12 wk of treatment, 7 out of 8 patients had biochemical response and EVR and 1 had biochemical response but persistent viremia. We had to reduce the dose of pegylated-interferon to 135 μg/wk in 2 cases. Three out of 6 (50%) patients had SVR 24 wk after the end of the treatment. Intention-to-treat analysis showed that 3 out of 10 patients (30%) had SVR. Side-effects occurred in most of the patients (flu-like syndrome, thrombocytopenia or leucopoenia), but they did not impose the discontinuation of treatment. CONCLUSION: After 12 wk of treatment with Peg-Interferon alpha 2a (40 ku) in patients on chronic haemodialysis with chronic C hepatitis, EVR was obtained in 87.5% (7/8) of the cases. SVR was achieved in 50% of the cases (3/6 patients) that finished the 48 wk of treatment.
基金Project(2009ZE56014)supported by the Aeronautical Science Foundation of ChinaProject(gf200901008)supported by the Open Fund of National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University,China
文摘The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to a true strain of 0.70 in the temperature range of 750-950°C and strain rate range of 0.001-10 s-1.The corresponding microstructures were observed by means of the metallurgical microscopy and scanning electron microscopy(SEM).It was found that all cavities occurred at the bulge regions of the compression specimens.Most of cavities nucleated along prior beta boundaries oriented 45°to the compression axis,while others nucleated at the interfaces of lamellar alpha colonies.Cavity nucleation was inhibited with increasing the volume fraction of beta phase and the volume fraction spheroidized of lamellar alpha phase.
基金supported by Consejo Nacional de Ciencia y Tecnología(CONACy T)project CB 2016-287614(to RGP and ABN)by Scholarship Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica de la Universidad Nacional Autónoma de México(PAPIIT-UNAM)IA203319 and PAPIIT-UNAM IN216221 to(LERL)。
文摘Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.