The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These g...The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These genes encode polytopic membrane proteins that feature an MtN3/saliva domain, also known as a PQ loop repeat, The rice MtN3/saliva/SWEET gene family consists of 21 members and is among the largest families in sequenced organisms. Accumulating data suggest that these genes are involved in multiple physiological processes, including reproductive development, senescence, environmental adaptation, and host-pathogen interaction, in different species. In rice, some members of the family, including Xa13/Os8N3/OsSWEET11, which is essential for reproductive development, are used by the pathogenic bacterium Xanthomonas oryzae pv. oryzae to invade its host. Emerging data have also revealed that at least some MtN3/saliva/SWEET-type proteins may regulate different physiological processes by facilitating ion transport via interaction with ion transporters or as sugar transporters. The accumulating knowledge about MtN3/saliva/SWEET- type genes will help to elucidate the molecular bases of their function in different organisms.展开更多
A unified approach called partition-and-recur for developing efficient and correct algorithmic programs is presented. An algorithm (represented by recurrence and initiation) is separated from program, and special att...A unified approach called partition-and-recur for developing efficient and correct algorithmic programs is presented. An algorithm (represented by recurrence and initiation) is separated from program, and special attention is paid to algorithm manipulation rather than program calculus. An algorithm is exactly a set of mathematical formulae. It is easier for formal derivation and proof. After getting efficient and correct algorithm, a trivial transformation is used to get a final program. The approach covers several known algorithm design techniques, e.g. dynamic programming, greedy, divide-and-conquer and enumeration, etc. The techniques of partition and recurrence are not new. Partition is a general approach for dealing with complicated objects and is typically used in divide-and-conquer approach. Recurrence is used in algorithm analysis, in developing loop invariants and dynamic programming approach. The main contribution is combining two techniques used in typical algorithm development into a unified and systematic approach to develop general efficient algorithmic programs and presenting a new representation of algorithm that is easier for understanding and demonstrating the correctness and ingenuity of algorithmic programs.展开更多
AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or...AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or rebleeding at our endoscopy center between January 2005 and July 2010.were included in this study.The early rebleeding cases after EVL were confirmed by clinical signs or endoscopy.A case-control study was performed comparing the patients presenting with early rebleeding with those without this complication.RESULTS: The incidence of early rebleeding after EVL was 7.60%,and the morbidity of rebleeding was 26.9%.Stepwise multivariate logistic regression analysis showed that four variables were independent risk factors for early rebleeding: moderate to excessive ascites [odds ratio (OR) 62.83,95% CI: 9.39-420.56,P < 0.001],the number of bands placed (OR 17.36,95% CI: 4.00-75.34,P < 0.001),the extent of varices (OR 15.41,95% CI: 2.84-83.52,P = 0.002) and prothrombin time (PT) > 18 s (OR 11.35,95% CI: 1.93-66.70,P = 0.007).CONCLUSION: The early rebleeding rate after EVL is mainly affected by the volume of ascites,number of rubber bands used to ligate,severity of varices and prolonged PT.Effective measures for prevention and treatment should be adopted before and after EVL.展开更多
The loop invariants take a very important role in the design,proof and derivation of the algorithmic program.We point out the limitations of the traditional standard strategy for developing loop invariants, and propos...The loop invariants take a very important role in the design,proof and derivation of the algorithmic program.We point out the limitations of the traditional standard strategy for developing loop invariants, and propose two new strategies for proving the existing algorithmic program and developing new ones. The strategies use recurrence as vehicle and integrate some effective methods of designing algorithms, e.g.Dynamic Programming,Greedy and Divide Conquer,into the recurrence relation of problem solving sequence.This lets us get straightforward an approach for solving a variety of complicated prob- lems,and makes the standard proof and formal derivation of their algorithmic programs possible.We show the method and advantages of applying the strategies with several typical nontrivial examples.展开更多
Macrophages are typically identified as classically activated(M1) macrophages and alternatively activated(M2) macrophages,which respectively exhibit pro-and anti-inflammatory phenotypes,and the balance between these t...Macrophages are typically identified as classically activated(M1) macrophages and alternatively activated(M2) macrophages,which respectively exhibit pro-and anti-inflammatory phenotypes,and the balance between these two subtypes plays a critical role in the regulation of tissue inflammation,injury,and repair processes.Recent studies indicate that tissue cells and macrophages interact via the release of small extracellular vesicles(EVs) in processes where EVs released by stressed tissue cells can promote the activation and polarization of adjacent macrophages which can in turn release EVs and factors that can promote cell stress and tissue inflammation and injury and vice versa.This review discusses the roles of such EVs in resulating such interactions to influence tissue inflammation and injury in a number of acute and chronic inflammatory disease conditions,and the potential applications,advantage and concerns for using EV-based therapeutic approaches to treat such conditions,including their potential role of drug carriers for the treatment of infectious diseases.展开更多
基金This work was supported by grants from the National Program on the Development of Basic Research in China （2012CB114005）the National Program of High Technology Development of China （2012AA10A303） and the National Natural Science Foundation of China （31100875）No conflict of interest declared.
文摘The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These genes encode polytopic membrane proteins that feature an MtN3/saliva domain, also known as a PQ loop repeat, The rice MtN3/saliva/SWEET gene family consists of 21 members and is among the largest families in sequenced organisms. Accumulating data suggest that these genes are involved in multiple physiological processes, including reproductive development, senescence, environmental adaptation, and host-pathogen interaction, in different species. In rice, some members of the family, including Xa13/Os8N3/OsSWEET11, which is essential for reproductive development, are used by the pathogenic bacterium Xanthomonas oryzae pv. oryzae to invade its host. Emerging data have also revealed that at least some MtN3/saliva/SWEET-type proteins may regulate different physiological processes by facilitating ion transport via interaction with ion transporters or as sugar transporters. The accumulating knowledge about MtN3/saliva/SWEET- type genes will help to elucidate the molecular bases of their function in different organisms.
基金the 863 Hi-Tech Programmethe National Natural ScienceFoundation of China
文摘A unified approach called partition-and-recur for developing efficient and correct algorithmic programs is presented. An algorithm (represented by recurrence and initiation) is separated from program, and special attention is paid to algorithm manipulation rather than program calculus. An algorithm is exactly a set of mathematical formulae. It is easier for formal derivation and proof. After getting efficient and correct algorithm, a trivial transformation is used to get a final program. The approach covers several known algorithm design techniques, e.g. dynamic programming, greedy, divide-and-conquer and enumeration, etc. The techniques of partition and recurrence are not new. Partition is a general approach for dealing with complicated objects and is typically used in divide-and-conquer approach. Recurrence is used in algorithm analysis, in developing loop invariants and dynamic programming approach. The main contribution is combining two techniques used in typical algorithm development into a unified and systematic approach to develop general efficient algorithmic programs and presenting a new representation of algorithm that is easier for understanding and demonstrating the correctness and ingenuity of algorithmic programs.
文摘AIM: To analyze the clinical risk factors for early variceal rebleeding after endoscopic variceal ligation (EVL).METHODS: 342 cirrhotic patients with esophageal varices who received elective EVL to prevent bleeding or rebleeding at our endoscopy center between January 2005 and July 2010.were included in this study.The early rebleeding cases after EVL were confirmed by clinical signs or endoscopy.A case-control study was performed comparing the patients presenting with early rebleeding with those without this complication.RESULTS: The incidence of early rebleeding after EVL was 7.60%,and the morbidity of rebleeding was 26.9%.Stepwise multivariate logistic regression analysis showed that four variables were independent risk factors for early rebleeding: moderate to excessive ascites [odds ratio (OR) 62.83,95% CI: 9.39-420.56,P < 0.001],the number of bands placed (OR 17.36,95% CI: 4.00-75.34,P < 0.001),the extent of varices (OR 15.41,95% CI: 2.84-83.52,P = 0.002) and prothrombin time (PT) > 18 s (OR 11.35,95% CI: 1.93-66.70,P = 0.007).CONCLUSION: The early rebleeding rate after EVL is mainly affected by the volume of ascites,number of rubber bands used to ligate,severity of varices and prolonged PT.Effective measures for prevention and treatment should be adopted before and after EVL.
基金This work was supported by the National Basic Research Program of China (No. 2004CB117506) and the National Natural Science Foundation of China (No. 30471239).
基金Research supported by the National Natural Science Foundation of China.
文摘The loop invariants take a very important role in the design,proof and derivation of the algorithmic program.We point out the limitations of the traditional standard strategy for developing loop invariants, and propose two new strategies for proving the existing algorithmic program and developing new ones. The strategies use recurrence as vehicle and integrate some effective methods of designing algorithms, e.g.Dynamic Programming,Greedy and Divide Conquer,into the recurrence relation of problem solving sequence.This lets us get straightforward an approach for solving a variety of complicated prob- lems,and makes the standard proof and formal derivation of their algorithmic programs possible.We show the method and advantages of applying the strategies with several typical nontrivial examples.
基金the support from Weatherhead Presidential Endowment Fund (USA)。
文摘Macrophages are typically identified as classically activated(M1) macrophages and alternatively activated(M2) macrophages,which respectively exhibit pro-and anti-inflammatory phenotypes,and the balance between these two subtypes plays a critical role in the regulation of tissue inflammation,injury,and repair processes.Recent studies indicate that tissue cells and macrophages interact via the release of small extracellular vesicles(EVs) in processes where EVs released by stressed tissue cells can promote the activation and polarization of adjacent macrophages which can in turn release EVs and factors that can promote cell stress and tissue inflammation and injury and vice versa.This review discusses the roles of such EVs in resulating such interactions to influence tissue inflammation and injury in a number of acute and chronic inflammatory disease conditions,and the potential applications,advantage and concerns for using EV-based therapeutic approaches to treat such conditions,including their potential role of drug carriers for the treatment of infectious diseases.
