The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollu...The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequent展开更多
Liver cancer ranks sixth in cancer incidence, and is the third leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the most common type of liver cancer, which arises from hepatocytes an...Liver cancer ranks sixth in cancer incidence, and is the third leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the most common type of liver cancer, which arises from hepatocytes and accounts for approximately 70%-85% of cases. Hepatitis B virus (HBV) frequently causes liver inflammation, hepatic damage and subsequent cirrhosis. Integrated viral DNA is found in 85%-90% of HBV-related HCCs. Its presence in tumors from non-cirrhotic livers of children or young adults further supports the role of viral DNA integration in hepatocarcinogenesis. Integration of subgenomic HBV DNA fragments into different locations within the host DNA is a significant feature of chronic HBV infection. Integration has two potential consequences: (1) the host genome becomes altered (“cis” effect); and (2) the HBV genome becomes altered (“trans” effect). The cis effect includes insertional mutagenesis, which can potentially disrupt host gene function or alter host gene regulation. Tumor progression is frequently associated with rearrangement and partial gain or loss of both viral and host sequences. However, the role of integrated HBV DNA in hepatocarcinogenesis remains controversial. Modern technology has provided a new paradigm to further our understanding of disease mechanisms. This review summarizes the role of HBV DNA integration in human carcinogenesis.展开更多
Powdered activated carbon（PAC） adsorption of two fishy odorants, trans,trans-2,4-heptadienal（HDE） and trans,trans-2,4-decadienal（DDE）, was investigated. Both the pseudo first-order and the pseudo second-order ki...Powdered activated carbon（PAC） adsorption of two fishy odorants, trans,trans-2,4-heptadienal（HDE） and trans,trans-2,4-decadienal（DDE）, was investigated. Both the pseudo first-order and the pseudo second-order kinetic models well described the kinetics curves, and DDE was more readily removed by PAC. In isotherm tests, both Freundlich and Modified Freundlich isotherms fitted the experimental data well. PAC exhibited a higher adsorption capacity for DDE than for HDE, which could be ascribed to the difference in their hydrophobicity. The calculated thermodynamic parameters（ΔG^0, ΔH^0, and ΔS^0） indicated an exothermic and spontaneous adsorption process. PAC dosage, p H, and natural organic matter（NOM） presence were found to influence the adsorption process. With increasing PAC dosage, the pseudo first-order and pseudo second-order rate constants both increased. The value of p H had little influence on HDE or DDE molecules but altered the surface charge of PAC, and the maximum adsorption capacity occurred at p H 9. The presence of NOM, especially the fraction with molecular weight less than1 k Dalton, hindered the adsorption. The study showed that preloaded NOM impaired the adsorption capacity of HDE or DDE more severely than simultaneously fed NOM did.展开更多
BACKGROUND Sarcopenia, i.e., muscle loss is now a well-recognized complication of cirrhosis and in cases of non-alcoholic fatty liver disease can contribute to accelerate liver fibrosis leading to cirrhosis. Hence, it...BACKGROUND Sarcopenia, i.e., muscle loss is now a well-recognized complication of cirrhosis and in cases of non-alcoholic fatty liver disease can contribute to accelerate liver fibrosis leading to cirrhosis. Hence, it is imperative to study interventions which targets to improve sarcopenia in cirrhosis.AIM To examine the relationship between interventions such nutritional supplementation, exercise, combined life style intervention, testosterone replacement and trans jugular intrahepatic portosystemic shunt(TIPS) to improve muscle mass in cirrhosis.METHODS We search PubMed, EMBASE and Cochrane between June-August 2018, without a limiting period and the types of articles(RCTs, clinical trial, comparative study)in adult patients with sarcopenia and cirrhosis. The primary outcome of interest was improvement in muscle mass, strength and physical function interventions mentioned above. In the screening process, 154 full text articles were included in the review and 129 studies were excluded.RESULTS We identified 24 studies that met review inclusion criteria. The studies were diverse in terms of the design, setting, interventions, and outcome measurements.We performed only qualitative synthesis of evidence due to heterogeneity amongst studies. Risk of bias was medium in most of the included studies and low quality of evidence showed improvement in the muscle mass, strength and physical function following aerobic exercise. 60% of the included studies on the nutritional intervention, 100% of the studies on testosterone replacement in hypogonadal men and trans-jugular portosystemic shunt were proved to be effective in improving sarcopenia in cirrhosis.CONCLUSION Although the quality of evidence is low, the findings of our systematic review suggest improvement in the sarcopenia in cirrhosis with exercise, nutritional interventions, hormonal and TIPS interventions. High quality randomized controlled trials needed to further strengthen these findings.展开更多
Coordinated transcriptional control employing synthetic promoters and transcription factors （TFs） can be used to achieve customized regulation of gene expression in planta. Synthetic promoter technology has yielded ...Coordinated transcriptional control employing synthetic promoters and transcription factors （TFs） can be used to achieve customized regulation of gene expression in planta. Synthetic promoter technology has yielded a series of promoters with modified cis-regulatory elements that provide useful tools for efficient modulation of gene expression. In addition, the use of zinc fingers （ZFs）, transcription activator-like effectors （TALEs）, and catalytically inactive clustered regularly interspaced short palindromic repeats （CRISPR）-associated protein 9 （dCas9） has made it feasible to engineer TFs that can produce targeted gene expression regulation; these approaches are particularly effective when artificial TFs are coupled with transcriptional activators or repressors. This review focuses on strategies used to engineer both promoters and TFs in the context of targeted transcriptional regulation. We also discuss the creation of synthetic inducible platforms, which can be used to impart stress tolerance to plants. We propose that combinatorial ＂cis-trans engineering＂ using a CRISPR-dCas9-based bipartite module could be used to regulate the expression of multiple target genes. This approach provides an attractive tool for introduction of specific qualitative traits into plants, thus enhancing their overall environmental adaptability.展开更多
Objective To investigate the effects of oral administration of all trans retinoic acid (ATRA) on inhibition of intimal thickening after balloon angioplasty in the rabbit iliac artery atherosclerotic model. Methods ...Objective To investigate the effects of oral administration of all trans retinoic acid (ATRA) on inhibition of intimal thickening after balloon angioplasty in the rabbit iliac artery atherosclerotic model. Methods Iliac atherosclerosis was induced in 24 rabbits, and balloon angioplasty was performed. At angioplasty, 24 rabbits were randomly divided into four groups (n=6 per group): Group 1: controls not receiving oral ATRA administration; Group 2: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning 1 week prior to angioplasty and continuing for 4 weeks; Group 3: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning immediately after angioplasty and continuing for 4 wk; Group 4: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning 1 wk after angioplasty and continuing for 4 wk. Values of cross sectional area, ratio of intimal/medial area and thickness were determined by a computer based morphometric system, and cell proliferative activity was assessed by 3 H thymidine incorporation.Results Both the cross sectional area and the ratio of intimal/medial area and thickness were significantly reduced by ATRA administration compared with control group (P<0.01). The inhibitory effect is less potent when ATRA is administered 1 week before angioplasty. The ATRA inhibitory effect when administered 1 week after angioplasty is not different significantly form that when administered immediately after angioplasty. The 3H thymidine incorporation was also decreased in ATRA treated rabbits compared with controls (P<0.01). Conclusions Oral ATRA administration can be effective in inhibiting intimal thickening after balloon angioplasty. It is reasonable that ATRA should be administered immediately after angioplasty.展开更多
Emerging evidence suggests that dietary fats may influence testicular function. However, most of the published literature on this field has used semen quality parameters as the only proxy for testicular function. We e...Emerging evidence suggests that dietary fats may influence testicular function. However, most of the published literature on this field has used semen quality parameters as the only proxy for testicular function. We examined the association of fat intake with circulating reproductive hormone levels and testicular volume among healthy young Spanish men. This is a cross-sectional study among 209 healthy male volunteers conducted between October 2010 and November 2011 in Murcia Region of Spain. Participants completed questionnaires on lifestyle, diet, and smoking, and each underwent a physical examination, and provided a blood sample. Linear regression was used to examine the association between each fatty acid type and reproductive hormone levels and testicular volumes. Monounsaturated fatty acids intake was inversely associated with serum blood levels of calculated free testosterone, total testosterone, and inhibin B. A positive association was observed between the intake of polyunsaturated fatty acids, particularly of omega-6 polyunsaturated fatty acids, and luteinizing hormone concentrations. In addition, the intake of trans fatty acids was associated with lower total testosterone and calculated free testosterone concentrations （Ptrend = 0.01 and 0.02, respectively）. The intake of omega-3 polyunsaturated fatty acids was positively related to testicular volume while the intake of omega-6 polyunsaturated fatty acids and trans fatty acids was inversely related to testicular volume. These data suggest that fat intake, and particularly intake of omega 3, omega 6, and trans fatty acids, may influence testicular function.展开更多
骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K...骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K共1184名患者骨盆CT影像,其中包含骶骨、左髋骨、右髋骨和腰椎四个部位标签。以3D U-Net骨干网络为基础,结合自注意力机制提出3D多类分割模型3D Trans U-Net,并使用迁移学习训练3D U-Net、V-Net、Attention U-Net作为对照实验。实验结果表明:3D Trans U-Net在测试集上整个骨盆区域、骶骨、左髋骨、右髋骨、腰椎Dice系数分别达到97.99%,96.70%,97.96%,97.95%,96.89%;Dice系数、豪斯多夫距离等评价指标均优于现有经典网络3D U-Net、V-Net、Attention U-Net。因此,改进的3D Trans U-Net对骨盆不同部位具有较好的分割效果,为精准医治骨盆骨疾病提供了一条有效的技术途径。展开更多
文摘The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequent
文摘Liver cancer ranks sixth in cancer incidence, and is the third leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the most common type of liver cancer, which arises from hepatocytes and accounts for approximately 70%-85% of cases. Hepatitis B virus (HBV) frequently causes liver inflammation, hepatic damage and subsequent cirrhosis. Integrated viral DNA is found in 85%-90% of HBV-related HCCs. Its presence in tumors from non-cirrhotic livers of children or young adults further supports the role of viral DNA integration in hepatocarcinogenesis. Integration of subgenomic HBV DNA fragments into different locations within the host DNA is a significant feature of chronic HBV infection. Integration has two potential consequences: (1) the host genome becomes altered (“cis” effect); and (2) the HBV genome becomes altered (“trans” effect). The cis effect includes insertional mutagenesis, which can potentially disrupt host gene function or alter host gene regulation. Tumor progression is frequently associated with rearrangement and partial gain or loss of both viral and host sequences. However, the role of integrated HBV DNA in hepatocarcinogenesis remains controversial. Modern technology has provided a new paradigm to further our understanding of disease mechanisms. This review summarizes the role of HBV DNA integration in human carcinogenesis.
基金supported by the National Natural Science Foundation of China (No. 51290284)
文摘Powdered activated carbon（PAC） adsorption of two fishy odorants, trans,trans-2,4-heptadienal（HDE） and trans,trans-2,4-decadienal（DDE）, was investigated. Both the pseudo first-order and the pseudo second-order kinetic models well described the kinetics curves, and DDE was more readily removed by PAC. In isotherm tests, both Freundlich and Modified Freundlich isotherms fitted the experimental data well. PAC exhibited a higher adsorption capacity for DDE than for HDE, which could be ascribed to the difference in their hydrophobicity. The calculated thermodynamic parameters（ΔG^0, ΔH^0, and ΔS^0） indicated an exothermic and spontaneous adsorption process. PAC dosage, p H, and natural organic matter（NOM） presence were found to influence the adsorption process. With increasing PAC dosage, the pseudo first-order and pseudo second-order rate constants both increased. The value of p H had little influence on HDE or DDE molecules but altered the surface charge of PAC, and the maximum adsorption capacity occurred at p H 9. The presence of NOM, especially the fraction with molecular weight less than1 k Dalton, hindered the adsorption. The study showed that preloaded NOM impaired the adsorption capacity of HDE or DDE more severely than simultaneously fed NOM did.
文摘BACKGROUND Sarcopenia, i.e., muscle loss is now a well-recognized complication of cirrhosis and in cases of non-alcoholic fatty liver disease can contribute to accelerate liver fibrosis leading to cirrhosis. Hence, it is imperative to study interventions which targets to improve sarcopenia in cirrhosis.AIM To examine the relationship between interventions such nutritional supplementation, exercise, combined life style intervention, testosterone replacement and trans jugular intrahepatic portosystemic shunt(TIPS) to improve muscle mass in cirrhosis.METHODS We search PubMed, EMBASE and Cochrane between June-August 2018, without a limiting period and the types of articles(RCTs, clinical trial, comparative study)in adult patients with sarcopenia and cirrhosis. The primary outcome of interest was improvement in muscle mass, strength and physical function interventions mentioned above. In the screening process, 154 full text articles were included in the review and 129 studies were excluded.RESULTS We identified 24 studies that met review inclusion criteria. The studies were diverse in terms of the design, setting, interventions, and outcome measurements.We performed only qualitative synthesis of evidence due to heterogeneity amongst studies. Risk of bias was medium in most of the included studies and low quality of evidence showed improvement in the muscle mass, strength and physical function following aerobic exercise. 60% of the included studies on the nutritional intervention, 100% of the studies on testosterone replacement in hypogonadal men and trans-jugular portosystemic shunt were proved to be effective in improving sarcopenia in cirrhosis.CONCLUSION Although the quality of evidence is low, the findings of our systematic review suggest improvement in the sarcopenia in cirrhosis with exercise, nutritional interventions, hormonal and TIPS interventions. High quality randomized controlled trials needed to further strengthen these findings.
文摘Coordinated transcriptional control employing synthetic promoters and transcription factors （TFs） can be used to achieve customized regulation of gene expression in planta. Synthetic promoter technology has yielded a series of promoters with modified cis-regulatory elements that provide useful tools for efficient modulation of gene expression. In addition, the use of zinc fingers （ZFs）, transcription activator-like effectors （TALEs）, and catalytically inactive clustered regularly interspaced short palindromic repeats （CRISPR）-associated protein 9 （dCas9） has made it feasible to engineer TFs that can produce targeted gene expression regulation; these approaches are particularly effective when artificial TFs are coupled with transcriptional activators or repressors. This review focuses on strategies used to engineer both promoters and TFs in the context of targeted transcriptional regulation. We also discuss the creation of synthetic inducible platforms, which can be used to impart stress tolerance to plants. We propose that combinatorial ＂cis-trans engineering＂ using a CRISPR-dCas9-based bipartite module could be used to regulate the expression of multiple target genes. This approach provides an attractive tool for introduction of specific qualitative traits into plants, thus enhancing their overall environmental adaptability.
文摘Objective To investigate the effects of oral administration of all trans retinoic acid (ATRA) on inhibition of intimal thickening after balloon angioplasty in the rabbit iliac artery atherosclerotic model. Methods Iliac atherosclerosis was induced in 24 rabbits, and balloon angioplasty was performed. At angioplasty, 24 rabbits were randomly divided into four groups (n=6 per group): Group 1: controls not receiving oral ATRA administration; Group 2: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning 1 week prior to angioplasty and continuing for 4 weeks; Group 3: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning immediately after angioplasty and continuing for 4 wk; Group 4: receiving oral ATRA (0.6 mg·kg 1 ·d 1 ) administration beginning 1 wk after angioplasty and continuing for 4 wk. Values of cross sectional area, ratio of intimal/medial area and thickness were determined by a computer based morphometric system, and cell proliferative activity was assessed by 3 H thymidine incorporation.Results Both the cross sectional area and the ratio of intimal/medial area and thickness were significantly reduced by ATRA administration compared with control group (P<0.01). The inhibitory effect is less potent when ATRA is administered 1 week before angioplasty. The ATRA inhibitory effect when administered 1 week after angioplasty is not different significantly form that when administered immediately after angioplasty. The 3H thymidine incorporation was also decreased in ATRA treated rabbits compared with controls (P<0.01). Conclusions Oral ATRA administration can be effective in inhibiting intimal thickening after balloon angioplasty. It is reasonable that ATRA should be administered immediately after angioplasty.
文摘Emerging evidence suggests that dietary fats may influence testicular function. However, most of the published literature on this field has used semen quality parameters as the only proxy for testicular function. We examined the association of fat intake with circulating reproductive hormone levels and testicular volume among healthy young Spanish men. This is a cross-sectional study among 209 healthy male volunteers conducted between October 2010 and November 2011 in Murcia Region of Spain. Participants completed questionnaires on lifestyle, diet, and smoking, and each underwent a physical examination, and provided a blood sample. Linear regression was used to examine the association between each fatty acid type and reproductive hormone levels and testicular volumes. Monounsaturated fatty acids intake was inversely associated with serum blood levels of calculated free testosterone, total testosterone, and inhibin B. A positive association was observed between the intake of polyunsaturated fatty acids, particularly of omega-6 polyunsaturated fatty acids, and luteinizing hormone concentrations. In addition, the intake of trans fatty acids was associated with lower total testosterone and calculated free testosterone concentrations （Ptrend = 0.01 and 0.02, respectively）. The intake of omega-3 polyunsaturated fatty acids was positively related to testicular volume while the intake of omega-6 polyunsaturated fatty acids and trans fatty acids was inversely related to testicular volume. These data suggest that fat intake, and particularly intake of omega 3, omega 6, and trans fatty acids, may influence testicular function.
文摘骨盆CT影像精确分割是骨盆骨疾病的临床诊断和手术规划中非常重要的环节。针对目前2D骨盆分割方法对三维医学影像进行切片处理时损失空间信息的问题,提出了改进3D U-Net网络实现对骨盆CT影像3D自动分割。实验数据为公开数据集CTPelvic1K共1184名患者骨盆CT影像,其中包含骶骨、左髋骨、右髋骨和腰椎四个部位标签。以3D U-Net骨干网络为基础,结合自注意力机制提出3D多类分割模型3D Trans U-Net,并使用迁移学习训练3D U-Net、V-Net、Attention U-Net作为对照实验。实验结果表明:3D Trans U-Net在测试集上整个骨盆区域、骶骨、左髋骨、右髋骨、腰椎Dice系数分别达到97.99%,96.70%,97.96%,97.95%,96.89%;Dice系数、豪斯多夫距离等评价指标均优于现有经典网络3D U-Net、V-Net、Attention U-Net。因此,改进的3D Trans U-Net对骨盆不同部位具有较好的分割效果,为精准医治骨盆骨疾病提供了一条有效的技术途径。
