INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relatio...INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relationship between expression of multidrugresistance (MDR) phenotype P-glycoprotein (P-gp)and the malignant properties of tumors, but theresults are often conflicting[1-8]. The difference intumor types or MDR phenotype induced by specificagents might account for this discrepancy. Taxotere(TXT), a member of the family of taxanes, hasantitumor activity through its effect of promotingthe polymerization of tubulin[9,10].展开更多
As chondroitinase ABC can improve the hostile microenvironment and cell transplantation is proven to be effective after spinal cord injury, we hypothesized that their combination would be a more effective treatment op...As chondroitinase ABC can improve the hostile microenvironment and cell transplantation is proven to be effective after spinal cord injury, we hypothesized that their combination would be a more effective treatment option. At 5 days after T8 spinal cord crush injury, rats were injected with bone marrow mesenchymal stem cell suspension or chondroitinase ABC 1 mm from the edge of spinal cord damage zone. Chondroitinase ABC was first injected, and bone marrow mesenchymal stem cell suspension was injected on the next day in the combination group. At 14 days, the mean Basso, Beattie and Bresnahan score of the rats in the combination group was higher than other groups. Hematoxylin-eosin staining showed that the necrotic area was significantly reduced in the combination group compared with other groups. Glial fibrillary acidic protein-chondroitin sulfate proteoglycan double staining showed that the damage zone of astrocytic scars was significantly reduced without the cavity in the combination group. Glial fibrillary acidic protein/growth associated protein-43 double immunostaining revealed that positive fibers traversed the damage zone in the combination group. These results suggest that the combination of chondroitinase ABC and bone marrow mesenchymal stem cell transplantation contributes to the repair of spinal cord injury.展开更多
Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain,such as a heparan,dermatan,chondroitin,or keratan sulfate,covalently attached to the protein core.These molecules arecategorized...Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain,such as a heparan,dermatan,chondroitin,or keratan sulfate,covalently attached to the protein core.These molecules arecategorized based on their structure,localization,and function,and can be found in the extracellular matrix,on the cell surface,and in the cytoplasm.Cell-surface heparan sulfate proteoglycans,such as syndecans,are the primary type present in healthy liver tissue.However,deterioration of the liver results in overproduction of other proteoglycan types.The purpose of this article is to provide a current summary of the most relevant data implicating proteoglycans in the development and progression of human and experimental liver cancer.A review of our work and other studies in the literature indicate that deterioration of liver function is accompanied by an increase in the amount of chondroitin sulfate proteoglycans.The alteration of proteoglycan composition interferes with the physiologic function of the liver on several levels.This article details and discusses the roles of syndecan-1,glypicans,agrin,perlecan,collagen XVIII/endostatin,endocan,serglycin,decorin,biglycan,asporin,fibromodulin,lumican,and versican in liver function.Specifically,glypicans,agrin,and versican play significant roles in the development of liver cancer.Conversely,the presence of decorin could potentially provide protective effects.展开更多
Proteoglycans in the central nervous system play integral roles as "traffic signals" for the direction of neurite outgrowth. This attribute of proteoglycans is a major factor in regeneration of the injured central n...Proteoglycans in the central nervous system play integral roles as "traffic signals" for the direction of neurite outgrowth. This attribute of proteoglycans is a major factor in regeneration of the injured central nervous system. In this review, the structures of proteoglycans and the evidence suggesting their involvement in the response following spinal cord injury are presented. The review further describes the methods routinely used to determine the effect proteoglycans have on neurite outgrowth. The effects of proteoglycans on neurite outgrowth are not completely understood as there is disagreement on what component of the molecule is interacting with growing neurites and this ambiguity is chronicled in an historical context. Finally, the most recent findings suggesting possible receptors, interactions, and sulfation patterns that may be important in eliciting the effect of proteoglycans on neurite outgrowth are discussed. A greater understanding of the proteoglycan-neurite interaction is necessary for successfully promoting regeneration in the iniured central nervous system.展开更多
A long-standing goal of spinal cord injury research is to develop effective repair strategies,which can restore motor and sensory functions to near-normal levels.Recent advances in clinical management of spinal cord i...A long-standing goal of spinal cord injury research is to develop effective repair strategies,which can restore motor and sensory functions to near-normal levels.Recent advances in clinical management of spinal cord injury have significantly improved the prognosis,survival rate and quality of life in patients with spinal cord injury.In addition,a significant progress in basic science research has unraveled the underlying cellular and molecular events of spinal cord injury.Such efforts enabled the development of pharmacologic agents,biomaterials and stem-cell based therapy.Despite these efforts,there is still no standard care to regenerate axons or restore function of silent axons in the injured spinal cord.These challenges led to an increased focus on another therapeutic approach,namely neuromodulation.In multiple animal models of spinal cord injury,epidural electrical stimulation of the spinal cord has demonstrated a recovery of motor function.Emerging evidence regarding the efficacy of epidural electrical stimulation has further expanded the potential of epidural electrical stimulation for treating patients with spinal cord injury.However,most clinical studies were conducted on a very small number of patients with a wide range of spinal cord injury.Thus,subsequent studies are essential to evaluate the therapeutic potential of epidural electrical stimulation for spinal cord injury and to optimize stimulation parameters.Here,we discuss cellular and molecular events that continue to damage the injured spinal cord and impede neurological recovery following spinal cord injury.We also discuss and summarize the animal and human studies that evaluated epidural electrical stimulation in spinal cord injury.展开更多
基金Supported in part by phone-Poulenc Rorer Pharmaceuticals INC
文摘INTRODUCTIONDevelopment of drug-resistance to chemotherapyand subsequent metastasis of tumor are primarilyresponsible for treatment failure and the death fromcancer. There have been many previous studies onthe relationship between expression of multidrugresistance (MDR) phenotype P-glycoprotein (P-gp)and the malignant properties of tumors, but theresults are often conflicting[1-8]. The difference intumor types or MDR phenotype induced by specificagents might account for this discrepancy. Taxotere(TXT), a member of the family of taxanes, hasantitumor activity through its effect of promotingthe polymerization of tubulin[9,10].
文摘As chondroitinase ABC can improve the hostile microenvironment and cell transplantation is proven to be effective after spinal cord injury, we hypothesized that their combination would be a more effective treatment option. At 5 days after T8 spinal cord crush injury, rats were injected with bone marrow mesenchymal stem cell suspension or chondroitinase ABC 1 mm from the edge of spinal cord damage zone. Chondroitinase ABC was first injected, and bone marrow mesenchymal stem cell suspension was injected on the next day in the combination group. At 14 days, the mean Basso, Beattie and Bresnahan score of the rats in the combination group was higher than other groups. Hematoxylin-eosin staining showed that the necrotic area was significantly reduced in the combination group compared with other groups. Glial fibrillary acidic protein-chondroitin sulfate proteoglycan double staining showed that the damage zone of astrocytic scars was significantly reduced without the cavity in the combination group. Glial fibrillary acidic protein/growth associated protein-43 double immunostaining revealed that positive fibers traversed the damage zone in the combination group. These results suggest that the combination of chondroitinase ABC and bone marrow mesenchymal stem cell transplantation contributes to the repair of spinal cord injury.
基金Supported by Hungarian Research Fund(OTKA)(No.100904 to Kovalszky Iand No.105763 to Baghy K)
文摘Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain,such as a heparan,dermatan,chondroitin,or keratan sulfate,covalently attached to the protein core.These molecules arecategorized based on their structure,localization,and function,and can be found in the extracellular matrix,on the cell surface,and in the cytoplasm.Cell-surface heparan sulfate proteoglycans,such as syndecans,are the primary type present in healthy liver tissue.However,deterioration of the liver results in overproduction of other proteoglycan types.The purpose of this article is to provide a current summary of the most relevant data implicating proteoglycans in the development and progression of human and experimental liver cancer.A review of our work and other studies in the literature indicate that deterioration of liver function is accompanied by an increase in the amount of chondroitin sulfate proteoglycans.The alteration of proteoglycan composition interferes with the physiologic function of the liver on several levels.This article details and discusses the roles of syndecan-1,glypicans,agrin,perlecan,collagen XVIII/endostatin,endocan,serglycin,decorin,biglycan,asporin,fibromodulin,lumican,and versican in liver function.Specifically,glypicans,agrin,and versican play significant roles in the development of liver cancer.Conversely,the presence of decorin could potentially provide protective effects.
基金supported by the NIH(NS53470)the Kentucky Spinal Cord and Head Injury Research Trust(#10-11A)the Department of Defense,CDMRP(SC090248/W81XWH-10-1-0778)
文摘Proteoglycans in the central nervous system play integral roles as "traffic signals" for the direction of neurite outgrowth. This attribute of proteoglycans is a major factor in regeneration of the injured central nervous system. In this review, the structures of proteoglycans and the evidence suggesting their involvement in the response following spinal cord injury are presented. The review further describes the methods routinely used to determine the effect proteoglycans have on neurite outgrowth. The effects of proteoglycans on neurite outgrowth are not completely understood as there is disagreement on what component of the molecule is interacting with growing neurites and this ambiguity is chronicled in an historical context. Finally, the most recent findings suggesting possible receptors, interactions, and sulfation patterns that may be important in eliciting the effect of proteoglycans on neurite outgrowth are discussed. A greater understanding of the proteoglycan-neurite interaction is necessary for successfully promoting regeneration in the iniured central nervous system.
基金This work was supported by the Medical Scientist Training Program T32GM007250Predoctoral Training in Molecular Therapeutics Program T32GM008803(to EHC).
文摘A long-standing goal of spinal cord injury research is to develop effective repair strategies,which can restore motor and sensory functions to near-normal levels.Recent advances in clinical management of spinal cord injury have significantly improved the prognosis,survival rate and quality of life in patients with spinal cord injury.In addition,a significant progress in basic science research has unraveled the underlying cellular and molecular events of spinal cord injury.Such efforts enabled the development of pharmacologic agents,biomaterials and stem-cell based therapy.Despite these efforts,there is still no standard care to regenerate axons or restore function of silent axons in the injured spinal cord.These challenges led to an increased focus on another therapeutic approach,namely neuromodulation.In multiple animal models of spinal cord injury,epidural electrical stimulation of the spinal cord has demonstrated a recovery of motor function.Emerging evidence regarding the efficacy of epidural electrical stimulation has further expanded the potential of epidural electrical stimulation for treating patients with spinal cord injury.However,most clinical studies were conducted on a very small number of patients with a wide range of spinal cord injury.Thus,subsequent studies are essential to evaluate the therapeutic potential of epidural electrical stimulation for spinal cord injury and to optimize stimulation parameters.Here,we discuss cellular and molecular events that continue to damage the injured spinal cord and impede neurological recovery following spinal cord injury.We also discuss and summarize the animal and human studies that evaluated epidural electrical stimulation in spinal cord injury.