The insertion torque of a dental implant is an important indicator for the primary stability of dental implants.Thus,the preoperative prediction for the insertion torque is crucial to improve the success rate of impla...The insertion torque of a dental implant is an important indicator for the primary stability of dental implants.Thus,the preoperative prediction for the insertion torque is crucial to improve the success rate of implantation surgery.In this present research,an alternative method for prediction of implant torque was proposed.First,the mechanical model for the insertion torque was established based on an oblique cutting process.In the proposed mechanical model,three factors,including bone quality,implant geometry and surgical methods were considered in terms of bone-quality coefficients,chip load and insertion speeds,respectively.Then,the defined bone-quality coefficients for cancellous bone with the computed tomography(CT)value of 235–245,345–355 and 415–425 Hu were obtained by a series of insertion experiments of IS and ITI implants.Finally,the insertion experiments of DIO implants were carried out to verify the accuracy of developed model.The predicted insertion torques calculated by the mechanical model were compared with those acquired by insertion experiments,with good agreement,the relative error being less than 15%.This method allows the insertion torque for different implant types to be quickly established and enhances prediction accuracy by considering the effects of implants’geometries and surgical methods.展开更多
BACKGROUND： Aquaporin-4 （AQP4） is abundant in astrocytes, ependymal cells, and the choroid plexus, and is associated with cerebrospinal fluid formation and osmoregulation. AQP4 is speculated to be the hypothalamic ...BACKGROUND： Aquaporin-4 （AQP4） is abundant in astrocytes, ependymal cells, and the choroid plexus, and is associated with cerebrospinal fluid formation and osmoregulation. AQP4 is speculated to be the hypothalamic osmoreceptor and regulator of water balance. OBJECTIVE： To examine AQP4 expression and its role in cultured rat astrocytes after exposure to hypotonic medium. DESIGN, TIME AND SETTING： Randomized control experiment. This experiment was carried out in the Research Room of Neurobiology, Chongqing University of Medical Science, China, between April and October 2003. MATERIALS： Two-day-old newborn Wistar rats （n =20）, weighing 10- 15 g, were purchased from the Experimental Animal Center of Chongqing University of Medical Science, China. METHODS： Purified rat cerebral cortical astrocytes were isolated fiom Wistar rats for in vitro cell culture experiments. The cells were randomly divided into control and hypotonic groups. The in vitro cell edema model was established by exposing astrocytes to hypotonic medium （268, 254, or 240 mmol/L）. Cells in the control group were cultured in normal culture medium. MAIN OUTCOME MEASURES： Morphological changes in astrocytes were observed under an inverted microscope and a transmission electron microscope after cells were cultured for 3, 6, 12, or 24 hours with hypotonic medium or normal culture medium. In each group, AQP4 protein and mRNA expression were assessed by immunocytochemistry, in situ hybridization, and reverse transcription polymerase chain reaction at the different time points. RESULTS： After astrocytes were cultured for 3, 6, 12, or 24 hours with hypotonic medium （268, 254, 240 mmol/L）, they showed typical features of cell edema. In the control group, no astrocytes developed pathological changes. There were no significant changes in the AQP4 mRNA and protein expression in the control group at any of the time points alter astrocytes were cultured with normal culture medium （P 〉 0.05）. Compared with the control group, AQP4 mRNA and protein expression in the hypotonic group were remarkably increased at all time points after astrocytes cultured with hypotonic medium （268, 254, 240 mmol/L; P 〈 0.05）. AQP4 mRNA and protein expression increased with increasing exposure time and with decreasing concentration of the hypotonic medium. CONCLUSION： Hypotonic medium induced cell edema and increased AQP4 mRNA and protein expression. Up-regulated expression of AQP4 was correlated with hypotonic medium concentration in a time dependent manner.展开更多
Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw materials.In the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(GB...Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw materials.In the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(GBS),and the genetic diversity and population structure were analyzed.The results showed that 210,268 Single Nucleotide Polymorphisms(SNPs)were present in total,and the average poly-morphism information content(PIC)was 0.1642.Genetic diversity and population structure analyses suggested that these barley landraces were differentiated and could be divided into three sub-groups,with morphological traits of row-type and adherence of the hulls the main distinguishing factors between groups.Genotypes with similar or duplicated names were also investigated according to their genetic backgrounds and seed appearances.This study provided valuable information on barley landraces from the Shanghai region,and showed that all these barley landraces should be protected and used for future breeding programs.展开更多
基金Major Research&Development Program of Shandong Province(Grant No.2015GGX103043)Taishan Scholars Program of Shandong Province(Grant No.ts201712002).
文摘The insertion torque of a dental implant is an important indicator for the primary stability of dental implants.Thus,the preoperative prediction for the insertion torque is crucial to improve the success rate of implantation surgery.In this present research,an alternative method for prediction of implant torque was proposed.First,the mechanical model for the insertion torque was established based on an oblique cutting process.In the proposed mechanical model,three factors,including bone quality,implant geometry and surgical methods were considered in terms of bone-quality coefficients,chip load and insertion speeds,respectively.Then,the defined bone-quality coefficients for cancellous bone with the computed tomography(CT)value of 235–245,345–355 and 415–425 Hu were obtained by a series of insertion experiments of IS and ITI implants.Finally,the insertion experiments of DIO implants were carried out to verify the accuracy of developed model.The predicted insertion torques calculated by the mechanical model were compared with those acquired by insertion experiments,with good agreement,the relative error being less than 15%.This method allows the insertion torque for different implant types to be quickly established and enhances prediction accuracy by considering the effects of implants’geometries and surgical methods.
基金the National Natural Science Foundation of China, No.30070247
文摘BACKGROUND： Aquaporin-4 （AQP4） is abundant in astrocytes, ependymal cells, and the choroid plexus, and is associated with cerebrospinal fluid formation and osmoregulation. AQP4 is speculated to be the hypothalamic osmoreceptor and regulator of water balance. OBJECTIVE： To examine AQP4 expression and its role in cultured rat astrocytes after exposure to hypotonic medium. DESIGN, TIME AND SETTING： Randomized control experiment. This experiment was carried out in the Research Room of Neurobiology, Chongqing University of Medical Science, China, between April and October 2003. MATERIALS： Two-day-old newborn Wistar rats （n =20）, weighing 10- 15 g, were purchased from the Experimental Animal Center of Chongqing University of Medical Science, China. METHODS： Purified rat cerebral cortical astrocytes were isolated fiom Wistar rats for in vitro cell culture experiments. The cells were randomly divided into control and hypotonic groups. The in vitro cell edema model was established by exposing astrocytes to hypotonic medium （268, 254, or 240 mmol/L）. Cells in the control group were cultured in normal culture medium. MAIN OUTCOME MEASURES： Morphological changes in astrocytes were observed under an inverted microscope and a transmission electron microscope after cells were cultured for 3, 6, 12, or 24 hours with hypotonic medium or normal culture medium. In each group, AQP4 protein and mRNA expression were assessed by immunocytochemistry, in situ hybridization, and reverse transcription polymerase chain reaction at the different time points. RESULTS： After astrocytes were cultured for 3, 6, 12, or 24 hours with hypotonic medium （268, 254, 240 mmol/L）, they showed typical features of cell edema. In the control group, no astrocytes developed pathological changes. There were no significant changes in the AQP4 mRNA and protein expression in the control group at any of the time points alter astrocytes were cultured with normal culture medium （P 〉 0.05）. Compared with the control group, AQP4 mRNA and protein expression in the hypotonic group were remarkably increased at all time points after astrocytes cultured with hypotonic medium （268, 254, 240 mmol/L; P 〈 0.05）. AQP4 mRNA and protein expression increased with increasing exposure time and with decreasing concentration of the hypotonic medium. CONCLUSION： Hypotonic medium induced cell edema and increased AQP4 mRNA and protein expression. Up-regulated expression of AQP4 was correlated with hypotonic medium concentration in a time dependent manner.
基金funded by the Shanghai Agriculture Applied Technology Development Program(Grant No.2019-02-08-00-08-F01109)the Climbing Plan(Grant No.PG22211)and the Ear-Marked Fund for CARS(Grant No.CARS-05-01A-02)N.G.H.is supported at Rothamsted Research by the Biotechnology and Biological Sciences Research Council(BBSRC)via the Designing Future Wheat Programme(BB/P016855/1).
文摘Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw materials.In the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(GBS),and the genetic diversity and population structure were analyzed.The results showed that 210,268 Single Nucleotide Polymorphisms(SNPs)were present in total,and the average poly-morphism information content(PIC)was 0.1642.Genetic diversity and population structure analyses suggested that these barley landraces were differentiated and could be divided into three sub-groups,with morphological traits of row-type and adherence of the hulls the main distinguishing factors between groups.Genotypes with similar or duplicated names were also investigated according to their genetic backgrounds and seed appearances.This study provided valuable information on barley landraces from the Shanghai region,and showed that all these barley landraces should be protected and used for future breeding programs.
