Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically un...Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically unstable and tend to aggregate or sinter at elevated temperatures. This scenario is particularly true for supported nanogold catalysts because the gold nanostructures are easily sintered at high temperatures, under reaction conditions, or even during storage at ambient temperature. Here, we demonstrate that isolated Au single atoms dispersed on iron oxide nanocrystallites （Aul/FeOx） are much more sintering- resistant than Au nanostructures, and exhibit extremely high reaction stability for CO oxidation in a wide temperature range. Theoretical studies revealed that the positively charged and surface-anchored Aul atoms with high valent states formed significant covalent metal-support interactions （CMSIs）, thus providing the ultra-stability and remarkable catalytic performance. This work may provide insights and a new avenue for fabricating supported Au catalysts with ultra-high stability.展开更多
Hepatic steatosis affects 20% to 30% of the general adult population in the western world. Currently, the technique of choice for determining hepatic fat deposition and the stage of fibrosis is liver biopsy. However, ...Hepatic steatosis affects 20% to 30% of the general adult population in the western world. Currently, the technique of choice for determining hepatic fat deposition and the stage of fibrosis is liver biopsy. However, it is an invasive procedure and its use is limited, particularly in children. It may also be subject to sampling error. Non-invasive techniques such as ultrasound, computerised tomography (CT), magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) can detect hepatic steatosis, but currently cannot distinguish between simple steatosis and steatohepatitis, or stage the degree of fibrosis accurately. Ultrasound is widely used to detect hepatic steatosis, but its sensitivity is reduced in the morbidly obese and also in those with small amounts of fatty infiltration. It has been used to grade hepatic fat content, but this is subjective. CT can detect hepatic steatosis, but exposes subjects to ionising radiation, thus limiting its use in longitudinal studies and in children. Recently, magnetic resonance (MR) techniques using chemical shift imaging have provided a quantitative assessment of the degree of hepatic fatty infiltration, which correlates well with liver biopsy results in the same patients. Similarly, in vivo 1H MRS is a fast, safe, non-invasive method forthe quantification of intrahepatocellular lipid (IHCL) levels. Both techniques will be useful tools in future longitudinal clinical studies, either in examining the natural history of conditions causing hepatic steatosis (e.g. non-alcoholic fatty liver disease), or in testing new treatments for these conditions.展开更多
BACKGROUND Esophageo-gastro-duodenoscopy(EGD)is an important procedure used for detection and diagnosis of esophago-gastric lesions.There exists no consensus on the technique of examination.AIM To identify recent adva...BACKGROUND Esophageo-gastro-duodenoscopy(EGD)is an important procedure used for detection and diagnosis of esophago-gastric lesions.There exists no consensus on the technique of examination.AIM To identify recent advances in diagnostic EGDs to improve diagnostic yield.METHODS We queried the PubMed database for relevant articles published between January 2001 and August 2019 as well as hand searched references from recently published endoscopy guidelines.Keywords used included free text and MeSH terms addressing quality indicators and technological innovations in EGDs.Factors affecting diagnostic yield and EGD quality were identified and divided into the follow segments:Pre endoscopy preparation,sedation,examination schema,examination time,routine biopsy,image enhanced endoscopy and future developments.RESULTS We identified 120 relevant abstracts of which we utilized 67 of these studies in our review.Adequate pre-endoscopy preparation with simethicone and pronase increases gastric visibility.Proper sedation,especially with propofol,increases patient satisfaction after procedure and may improve detection of superficial gastrointestinal lesions.There is a movement towards mandatory picture documentation during EGD as well as dedicating sufficient time for examination improves diagnostic yield.The use of image enhanced endoscopy and magnifying endoscopy improves detection of squamous cell carcinoma and gastric neoplasm.The magnifying endoscopy simple diagnostic algorithm is useful for diagnosis of early gastric cancer.CONCLUSION There is a steady momentum in the past decade towards improving diagnostic yield,quality and reporting in EGDs.Other interesting innovations,such as Raman spectroscopy,endocytoscopy and artificial intelligence may have widespread endoscopic applications in the near future.展开更多
Photocatalysis has attracted worldwide attention due to its potential in solar energy conversion.As a ＂green＂ advanced oxidation technology, it has been extensively used for water disinfection and wastewater treatme...Photocatalysis has attracted worldwide attention due to its potential in solar energy conversion.As a ＂green＂ advanced oxidation technology, it has been extensively used for water disinfection and wastewater treatment. This article provides a review of the recent progress in solar energy-induced photocatalytic disinfection of bacteria, focusing on the development of highly efficient photocatalysts and their underlying mechanisms in bacterial inactivation. The photocatalysts are classified into Ti O2-based and non-Ti O2-based systems, as Ti O2 is the most investigated photocatalyst. The synthesis methods, modification strategies, bacterial disinfection activities and mechanisms of different types of photocatalysts are reviewed in detail.Emphasis is given to the modified Ti O2, including noble metal deposition, non-metal doping,dye sensitization and composite Ti O2, along with typical non-Ti O2-based photocatalysts for bacterial disinfection, including metal oxides, sulfides, bismuth metallates, graphene-based photocatalysts, carbon nitride-based photocatalysts and natural photocatalysts. A simple and versatile methodology by using a partition system combined with scavenging study is introduced to study the photocatalytic disinfection mechanisms in different photocatalytic systems. This review summarizes the current state of the work on photocatalytic disinfection of bacteria, and is expected to offer useful insights for the future development in the field.展开更多
AIM： To assess the effectiveness of the current UK clinical practice in reducing hepatic fat （IHCL）.METHODS： Whole body MRI and IH MRS were obtained, before and after 6 mo nutritional counselling, from liver, sole...AIM： To assess the effectiveness of the current UK clinical practice in reducing hepatic fat （IHCL）.METHODS： Whole body MRI and IH MRS were obtained, before and after 6 mo nutritional counselling, from liver, soleus and tibialis muscles in 10 subjects with non-alcoholic fatty liver disease （NAFLD）.RESULTS： A 500 Kcal-restricted diet resulted in an average weight loss of 4% （-3.4 kg,） accompanied by significant reductions in most adipose tissue （AT） depots, including subcutaneous （-9.9%）, abdominal subcutaneous （-10.2%） and intra-abdominal- AT （-11.4%）. Intramyocellular lipids （IMCL） were significantly reduced in the tibialis muscle （-28.2%）. Decreases in both IHCL （-39.9%） and soleus IMCL （-12.2%） content were also observed, although these were not significant. Several individuals showed dramatic decreases in IHCL, while others paradoxically showed increases in IHCL content. Changes in body composition were accompanied by improvements in certain liver function tests： serum aspartate aminotransferase （AST） and alanine aminotransferase （ALT）. Significant correlations were found between decreases in IHCL and reductions in both intra-abdominal and abdominal subcutaneous AT. Improvements in liver function tests were associated with reductions in intra-abdominal AT, but not with changes in IHCL. CONCLUSION： This study shows that even a very modest reduction in body weight achieved through lifestyle modification can result in changes in body fat depots and improvements in LETs.展开更多
Aim： To determine the effect of two different extracts of red maca in male rats. Methods： Prostatic hyperplasia was induced in male rats with testosterone enanthate （TE）. The study comprised six groups： one contr...Aim： To determine the effect of two different extracts of red maca in male rats. Methods： Prostatic hyperplasia was induced in male rats with testosterone enanthate （TE）. The study comprised six groups： one control group （group 1）, one group treated with TE （group 2）, two groups treated with TE and aqueous extract of red maca （groups 3 and 4）, one group treated with hydroalcoholic extract of red maca （group 5） and one group treated with finasteride （0.1 mg, group 6）. Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates （0.02-0.08 mg） in red maca extracts was assessed. Results： Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion： The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.展开更多
Telerobotic surgery is the most advanced development in the field of minimally invasive surgery. The da Vinci surgical system, which is currently the most widely used telerobotic device, was approved by the Food and D...Telerobotic surgery is the most advanced development in the field of minimally invasive surgery. The da Vinci surgical system, which is currently the most widely used telerobotic device, was approved by the Food and Drug Administration of the United States of America for clinical use in all abdominal operations in July 2000. The first da Vinci surgical system in China was installed in November 2005 at our institution. We herein report the first telerobotic-assisted laparoscopic abdominoperineal resection using the 3-arm da Vinci surgical system for low rectal cancer in Hong Kong and China, which was performed in August 2006. The operative time and blood loss were 240 min and 200 mL, respectively. There was no complication, and the patient was discharged on postoperative day five. An updated review of published literature on telerobotic-assisted colorectal surgery is included in this report, with special emphasis on its advantages and limitations.展开更多
文摘Supported noble metal nanoparticles （including nanoclusters） are widely used in many industrial catalytic processes. While the finely dispersed nanostructures are highly active, they are usually thermodynamically unstable and tend to aggregate or sinter at elevated temperatures. This scenario is particularly true for supported nanogold catalysts because the gold nanostructures are easily sintered at high temperatures, under reaction conditions, or even during storage at ambient temperature. Here, we demonstrate that isolated Au single atoms dispersed on iron oxide nanocrystallites （Aul/FeOx） are much more sintering- resistant than Au nanostructures, and exhibit extremely high reaction stability for CO oxidation in a wide temperature range. Theoretical studies revealed that the positively charged and surface-anchored Aul atoms with high valent states formed significant covalent metal-support interactions （CMSIs）, thus providing the ultra-stability and remarkable catalytic performance. This work may provide insights and a new avenue for fabricating supported Au catalysts with ultra-high stability.
基金Grants from the Novo Nordisk UK Research Foundation (supporting S.R.M)Pfizer Global Research and Development (Sandwich, UK)the British Medical Research Council and the United Kingdom Department of Health Research and Development Initiative
文摘Hepatic steatosis affects 20% to 30% of the general adult population in the western world. Currently, the technique of choice for determining hepatic fat deposition and the stage of fibrosis is liver biopsy. However, it is an invasive procedure and its use is limited, particularly in children. It may also be subject to sampling error. Non-invasive techniques such as ultrasound, computerised tomography (CT), magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) can detect hepatic steatosis, but currently cannot distinguish between simple steatosis and steatohepatitis, or stage the degree of fibrosis accurately. Ultrasound is widely used to detect hepatic steatosis, but its sensitivity is reduced in the morbidly obese and also in those with small amounts of fatty infiltration. It has been used to grade hepatic fat content, but this is subjective. CT can detect hepatic steatosis, but exposes subjects to ionising radiation, thus limiting its use in longitudinal studies and in children. Recently, magnetic resonance (MR) techniques using chemical shift imaging have provided a quantitative assessment of the degree of hepatic fatty infiltration, which correlates well with liver biopsy results in the same patients. Similarly, in vivo 1H MRS is a fast, safe, non-invasive method forthe quantification of intrahepatocellular lipid (IHCL) levels. Both techniques will be useful tools in future longitudinal clinical studies, either in examining the natural history of conditions causing hepatic steatosis (e.g. non-alcoholic fatty liver disease), or in testing new treatments for these conditions.
文摘BACKGROUND Esophageo-gastro-duodenoscopy(EGD)is an important procedure used for detection and diagnosis of esophago-gastric lesions.There exists no consensus on the technique of examination.AIM To identify recent advances in diagnostic EGDs to improve diagnostic yield.METHODS We queried the PubMed database for relevant articles published between January 2001 and August 2019 as well as hand searched references from recently published endoscopy guidelines.Keywords used included free text and MeSH terms addressing quality indicators and technological innovations in EGDs.Factors affecting diagnostic yield and EGD quality were identified and divided into the follow segments:Pre endoscopy preparation,sedation,examination schema,examination time,routine biopsy,image enhanced endoscopy and future developments.RESULTS We identified 120 relevant abstracts of which we utilized 67 of these studies in our review.Adequate pre-endoscopy preparation with simethicone and pronase increases gastric visibility.Proper sedation,especially with propofol,increases patient satisfaction after procedure and may improve detection of superficial gastrointestinal lesions.There is a movement towards mandatory picture documentation during EGD as well as dedicating sufficient time for examination improves diagnostic yield.The use of image enhanced endoscopy and magnifying endoscopy improves detection of squamous cell carcinoma and gastric neoplasm.The magnifying endoscopy simple diagnostic algorithm is useful for diagnosis of early gastric cancer.CONCLUSION There is a steady momentum in the past decade towards improving diagnostic yield,quality and reporting in EGDs.Other interesting innovations,such as Raman spectroscopy,endocytoscopy and artificial intelligence may have widespread endoscopic applications in the near future.
基金supported by research grants from Research Grant Council (GRF 478611)Innovation and Technology Commission (ITS/237/13) of Hong Kong SAR Government.P.K.supported by CAS/SAFEA International Partnership Program for Creative Research Teams of Chinese Academy of Sciences, China
文摘Photocatalysis has attracted worldwide attention due to its potential in solar energy conversion.As a ＂green＂ advanced oxidation technology, it has been extensively used for water disinfection and wastewater treatment. This article provides a review of the recent progress in solar energy-induced photocatalytic disinfection of bacteria, focusing on the development of highly efficient photocatalysts and their underlying mechanisms in bacterial inactivation. The photocatalysts are classified into Ti O2-based and non-Ti O2-based systems, as Ti O2 is the most investigated photocatalyst. The synthesis methods, modification strategies, bacterial disinfection activities and mechanisms of different types of photocatalysts are reviewed in detail.Emphasis is given to the modified Ti O2, including noble metal deposition, non-metal doping,dye sensitization and composite Ti O2, along with typical non-Ti O2-based photocatalysts for bacterial disinfection, including metal oxides, sulfides, bismuth metallates, graphene-based photocatalysts, carbon nitride-based photocatalysts and natural photocatalysts. A simple and versatile methodology by using a partition system combined with scavenging study is introduced to study the photocatalytic disinfection mechanisms in different photocatalytic systems. This review summarizes the current state of the work on photocatalytic disinfection of bacteria, and is expected to offer useful insights for the future development in the field.
基金supported by the National Natural Science Foundation of China (21067004, 21263005)the Science and Technology Project of the Education Department of Jiangxi Province (GJJ12344)+1 种基金the Young Scientists Cultivating Program of Jiangxi Province (20122BCB23015)the China Scholarship Council (2011836054)~~
基金Supported by the British Medical Research Council, United Kingdom, No. MRC CEG G99000178
文摘AIM： To assess the effectiveness of the current UK clinical practice in reducing hepatic fat （IHCL）.METHODS： Whole body MRI and IH MRS were obtained, before and after 6 mo nutritional counselling, from liver, soleus and tibialis muscles in 10 subjects with non-alcoholic fatty liver disease （NAFLD）.RESULTS： A 500 Kcal-restricted diet resulted in an average weight loss of 4% （-3.4 kg,） accompanied by significant reductions in most adipose tissue （AT） depots, including subcutaneous （-9.9%）, abdominal subcutaneous （-10.2%） and intra-abdominal- AT （-11.4%）. Intramyocellular lipids （IMCL） were significantly reduced in the tibialis muscle （-28.2%）. Decreases in both IHCL （-39.9%） and soleus IMCL （-12.2%） content were also observed, although these were not significant. Several individuals showed dramatic decreases in IHCL, while others paradoxically showed increases in IHCL content. Changes in body composition were accompanied by improvements in certain liver function tests： serum aspartate aminotransferase （AST） and alanine aminotransferase （ALT）. Significant correlations were found between decreases in IHCL and reductions in both intra-abdominal and abdominal subcutaneous AT. Improvements in liver function tests were associated with reductions in intra-abdominal AT, but not with changes in IHCL. CONCLUSION： This study shows that even a very modest reduction in body weight achieved through lifestyle modification can result in changes in body fat depots and improvements in LETs.
文摘Aim： To determine the effect of two different extracts of red maca in male rats. Methods： Prostatic hyperplasia was induced in male rats with testosterone enanthate （TE）. The study comprised six groups： one control group （group 1）, one group treated with TE （group 2）, two groups treated with TE and aqueous extract of red maca （groups 3 and 4）, one group treated with hydroalcoholic extract of red maca （group 5） and one group treated with finasteride （0.1 mg, group 6）. Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates （0.02-0.08 mg） in red maca extracts was assessed. Results： Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion： The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.
文摘Telerobotic surgery is the most advanced development in the field of minimally invasive surgery. The da Vinci surgical system, which is currently the most widely used telerobotic device, was approved by the Food and Drug Administration of the United States of America for clinical use in all abdominal operations in July 2000. The first da Vinci surgical system in China was installed in November 2005 at our institution. We herein report the first telerobotic-assisted laparoscopic abdominoperineal resection using the 3-arm da Vinci surgical system for low rectal cancer in Hong Kong and China, which was performed in August 2006. The operative time and blood loss were 240 min and 200 mL, respectively. There was no complication, and the patient was discharged on postoperative day five. An updated review of published literature on telerobotic-assisted colorectal surgery is included in this report, with special emphasis on its advantages and limitations.
