Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthet...Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthetic materials due to increased biocompatibility and reduced foreign body reaction within human tissues.However,we present a case report describing a patient who displayed rejection to a Permacol mesh when used in the repair of abdominal wound dehiscence following an emergency laparotomy.Review of the English language literature using PubMed and Medline, showed only two previously published cases of explantation of Permacoldue to sepsis or wound breakdown. The authors believe this is the first case of severe foreign body reaction leading to rejection of Permacol.Both animal and human studies show conflicting evidence of biocompatibility.There are several reports of successful use of Permacolto repair complex incisional herniae or abdominal walls in the presence of significant contamination.It appears from the literature that Permacolis a promising material,but as we have demonstrated,it has the potential to evoke a foreign body reaction and rejection in certain subjects.展开更多
Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively u...Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively under biaxial tensile condition with cruciform specimen. Effects of transverse constant tensile load on longitudinal tensile mechanical properties are indistinctive compared with corresponding uniaxial longitudinal tensile mechanical properties. It can be relative to larger difference between longitudinal and transverse mechanical properties. Its dominating failure mode is typical fiber dominated mode; However, Experiment results indicate that transverse mechanical properties of nylon cord rubber composite with longitudinal constant tensile loads are distinct from its uniaxial transverse tensile mechanical properties. It can be attribute to action of longitudinal tension that makes material rigidify in the direction perpendicular to fiber, Mode of failure is representative of matrix dominated failure. For the measurement of large deformation up to 50 percent, a special CCD imaging method is employed in the experimental investigation that makes measurement of large deformations more precise.展开更多
Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified w...Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified with surfactant （hexadecyl-trimethyl-ammonium bromide, CTAB） as a pore templating material. The synthesized samples were characterized by the transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption techniques. The results indicated that the mesoporous silica synthesized by using [bmim][BF4] and CTAB as mixed templates showed better mesostructural order and smaller pore size, compared with mesoporous silica materials synthesized by using single [bmim][BF4] as template under the same conditions. This indicates that the presence of surfactant can affect the microstructures of silica prepared by＇the present synthesis method.展开更多
There have been few reports concerning the hydrothermal synthesis of silicon anode materials. In this manuscript, starting from the very cheap silica sol, we hydrothermally prepared porous silicon nanospheres in an au...There have been few reports concerning the hydrothermal synthesis of silicon anode materials. In this manuscript, starting from the very cheap silica sol, we hydrothermally prepared porous silicon nanospheres in an autoclave at 180 ℃. As anode materials for lithium-ion batteries （LIBs）, the as-prepared nano-silicon anode without any carbon coating delivers a high reversible specific capacity of 2,650 mAh·g^-1 at 0.36 A·g^-1 and a significant cycling stability of about 950 mAh·g^-1 at 3.6 A·g^-1 during 500 cycles.展开更多
Objective: To investigate the effect of nano hydroxyapatite/collagen (nHA/collagen) composite as a graft extender and enhancer when combined with recombinant human bone morphogenetic protein 2 (rhBMP 2) on lumbar inte...Objective: To investigate the effect of nano hydroxyapatite/collagen (nHA/collagen) composite as a graft extender and enhancer when combined with recombinant human bone morphogenetic protein 2 (rhBMP 2) on lumbar intertransverse fusion in rabbits. Methods: Sixty four adult female New Zealand white rabbits, aged 1 year and weighing 3.5 4.5 kg, underwent similar posterolateral intertransverse process arthrodesis and were randomly divided into 4 groups based on different grafts: autogenous cancellous bone alone (ACB group), nHA/collagen alone (HAC group), half autogenous cancellous bone and half nHA/collagen (ACB+HAC group) and nHA/collagen combined with rhBMP 2 (HAC+BMP group). The fusion masses were analyzed by manual palpation, radiography, biomechanical testing and histological examination. Results: Fusion was observed in 4 cases in the 6th week and in 5 cases in the 10th week after surgery in ACB group. No case showed fusion in HAC group. In ACB+HAC group, there was fusion in 3 cases in the 6th week and in 4 cases in the 10th week after surgery. In HAC+BMP group, fusion in 1 case was found in the 4th week, in 5 cases in the 6th week and in 6 cases in the 10th week after surgery. It suggested that ACB, ACB+HAC and HAC+BMP groups showed similar fusion ratio and mechanical strength in the 6th and 10th week after surgery. According to the microstructure analysis of the samples, nHA/collagen had no negative effect when implanted together with ilium autograft. In HAC+BMP group, new bone like tissue was observed in the 2nd week postoperatively, and nearly all of the implanted composites were replaced by mature bone matrix and new bones in 10th week postoperatively. Conclusions: The nHA/collagen, especially combined with rhBMP 2, is a promising bone substitute, for it has quick biodegradation, fine bone bending ability, and high osteoconductivity on posterolateral spinal fusion in rabbits.展开更多
Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achie...Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achievement of the gelator molecules still needs good design and tedious organic synthesis.In this paper,we proposed a simple and general mixing approach to get the organogel for nearly all the organic compounds and even soluble nanoparticles without any modification.We have designed a universal gelator molecule,which forms organogels with more than 40 kinds of organic solvents from aploar to polar solvents.More interestingly,when other organic compounds or even nanomaterials,which are soluble in certain organic solvents,are mixed with this gelator molecule,they can form organogels no matter whether the individual compounds could form organogel or not.This method is applicable to nearly all kinds of soluble organic compounds and opens an efficient and universal way to fabricate gel materials.展开更多
文摘Permacol mesh has shown promise when used in abdominal wall repair,especially in the presence of a contaminated surgical field.This biomaterial,derived from porcine dermis collagen,has proposed advantages over synthetic materials due to increased biocompatibility and reduced foreign body reaction within human tissues.However,we present a case report describing a patient who displayed rejection to a Permacol mesh when used in the repair of abdominal wound dehiscence following an emergency laparotomy.Review of the English language literature using PubMed and Medline, showed only two previously published cases of explantation of Permacoldue to sepsis or wound breakdown. The authors believe this is the first case of severe foreign body reaction leading to rejection of Permacol.Both animal and human studies show conflicting evidence of biocompatibility.There are several reports of successful use of Permacolto repair complex incisional herniae or abdominal walls in the presence of significant contamination.It appears from the literature that Permacolis a promising material,but as we have demonstrated,it has the potential to evoke a foreign body reaction and rejection in certain subjects.
文摘Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively under biaxial tensile condition with cruciform specimen. Effects of transverse constant tensile load on longitudinal tensile mechanical properties are indistinctive compared with corresponding uniaxial longitudinal tensile mechanical properties. It can be relative to larger difference between longitudinal and transverse mechanical properties. Its dominating failure mode is typical fiber dominated mode; However, Experiment results indicate that transverse mechanical properties of nylon cord rubber composite with longitudinal constant tensile loads are distinct from its uniaxial transverse tensile mechanical properties. It can be attribute to action of longitudinal tension that makes material rigidify in the direction perpendicular to fiber, Mode of failure is representative of matrix dominated failure. For the measurement of large deformation up to 50 percent, a special CCD imaging method is employed in the experimental investigation that makes measurement of large deformations more precise.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.50564006）, the Natural Science Foundation From Science and Technology Committee of Yunnan （No.2005E0042）, and the Specialized Research Foundation for the Doctoral Program of Higher Education of China （No.20070674001）. We also thank Academician Si-shen Xie, Institute of Physics of Chinese Academy Sciences for helping with an SEM facility.
文摘Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified with surfactant （hexadecyl-trimethyl-ammonium bromide, CTAB） as a pore templating material. The synthesized samples were characterized by the transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption techniques. The results indicated that the mesoporous silica synthesized by using [bmim][BF4] and CTAB as mixed templates showed better mesostructural order and smaller pore size, compared with mesoporous silica materials synthesized by using single [bmim][BF4] as template under the same conditions. This indicates that the presence of surfactant can affect the microstructures of silica prepared by＇the present synthesis method.
文摘There have been few reports concerning the hydrothermal synthesis of silicon anode materials. In this manuscript, starting from the very cheap silica sol, we hydrothermally prepared porous silicon nanospheres in an autoclave at 180 ℃. As anode materials for lithium-ion batteries （LIBs）, the as-prepared nano-silicon anode without any carbon coating delivers a high reversible specific capacity of 2,650 mAh·g^-1 at 0.36 A·g^-1 and a significant cycling stability of about 950 mAh·g^-1 at 3.6 A·g^-1 during 500 cycles.
文摘Objective: To investigate the effect of nano hydroxyapatite/collagen (nHA/collagen) composite as a graft extender and enhancer when combined with recombinant human bone morphogenetic protein 2 (rhBMP 2) on lumbar intertransverse fusion in rabbits. Methods: Sixty four adult female New Zealand white rabbits, aged 1 year and weighing 3.5 4.5 kg, underwent similar posterolateral intertransverse process arthrodesis and were randomly divided into 4 groups based on different grafts: autogenous cancellous bone alone (ACB group), nHA/collagen alone (HAC group), half autogenous cancellous bone and half nHA/collagen (ACB+HAC group) and nHA/collagen combined with rhBMP 2 (HAC+BMP group). The fusion masses were analyzed by manual palpation, radiography, biomechanical testing and histological examination. Results: Fusion was observed in 4 cases in the 6th week and in 5 cases in the 10th week after surgery in ACB group. No case showed fusion in HAC group. In ACB+HAC group, there was fusion in 3 cases in the 6th week and in 4 cases in the 10th week after surgery. In HAC+BMP group, fusion in 1 case was found in the 4th week, in 5 cases in the 6th week and in 6 cases in the 10th week after surgery. It suggested that ACB, ACB+HAC and HAC+BMP groups showed similar fusion ratio and mechanical strength in the 6th and 10th week after surgery. According to the microstructure analysis of the samples, nHA/collagen had no negative effect when implanted together with ilium autograft. In HAC+BMP group, new bone like tissue was observed in the 2nd week postoperatively, and nearly all of the implanted composites were replaced by mature bone matrix and new bones in 10th week postoperatively. Conclusions: The nHA/collagen, especially combined with rhBMP 2, is a promising bone substitute, for it has quick biodegradation, fine bone bending ability, and high osteoconductivity on posterolateral spinal fusion in rabbits.
基金supported by the National Natural Science Foundation of China (50673095 and 21021003)the Basic Research Development Program (2007CB808005 and 2009CB930802)the Fund of the Chinese Academy of Sciences
文摘Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achievement of the gelator molecules still needs good design and tedious organic synthesis.In this paper,we proposed a simple and general mixing approach to get the organogel for nearly all the organic compounds and even soluble nanoparticles without any modification.We have designed a universal gelator molecule,which forms organogels with more than 40 kinds of organic solvents from aploar to polar solvents.More interestingly,when other organic compounds or even nanomaterials,which are soluble in certain organic solvents,are mixed with this gelator molecule,they can form organogels no matter whether the individual compounds could form organogel or not.This method is applicable to nearly all kinds of soluble organic compounds and opens an efficient and universal way to fabricate gel materials.
