BACKGROUND:The efficacy of clinical islet transplanta-tion has been demonstrated with autografts,and although islet allografts have established insulin independence in a small number of IDDM patients,the treatment is ...BACKGROUND:The efficacy of clinical islet transplanta-tion has been demonstrated with autografts,and although islet allografts have established insulin independence in a small number of IDDM patients,the treatment is con-founded by the necessity of central cell damage immuno-suppression,the lack of donor tissue,and recurring islet immunogenicity.These limitations underscore a need to develop therapies to serve the large population of diabetic patients.This study was designed to document central cell damage to isolated islets of Langerhans in hamsters and its prevention.METHODS:Islets were cultured at 37°C for 7-14 days after isolation,and then at 26°C for 2,4 and 7 days before addi-tional culture at 37°C for an additional 7 days.Central cell damage in the isolated islets was monitored by video-mi-croscopy and analyzed quantitatively by a computer-assis-ted image analysis system.The analysis included daily measurement of the diameter and the area of the isolated is-lets and the area of the central cell damage that developed in those islets over time during culture.Histological exami-nation and TdT-mediated dUTP-biotin nick end labeling(TUNEL)assay were used to characterize cell damage and to monitor islet function.RESULTS;Microscopic analysis showed that during the 7 to 14 days of culture at 37°C,central cell damage appeared in the larger islets with diameters greater than 200μm,which included both necrotic and apoptotic cell death.Low temperature(26°C)culture prevented central cell damage of isolated islets.The 7-day culture procedure at 26°C could inhibit most of the central cell(excluding diameters greater than 300μm)damage when the islets were re-warmed to 37°C.CONCLUSIONS:Our results indicate that central cell da-mage to isolated islets of Langerhans correlates with the size of the islets.Low temperature(26°C)culture can preventcentral cell damage to the isolated islets,and is capable to successfully precondition these islets for 37°C culture.These novel findings may help to understand the patho-physiology of early loss of islet tissue after transplantation,and may provide a new strategy to improve graft function in the clinical setting of islet transplantation.展开更多
For the mammalian brain to process and decipher the rich panoply of sounds that abound in the world, nature has evolved an elegant collection of neural circuits dedicated to this task. Indeed, the complexity, variety ...For the mammalian brain to process and decipher the rich panoply of sounds that abound in the world, nature has evolved an elegant collection of neural circuits dedicated to this task. Indeed, the complexity, variety and number of neural pathways devoted to computing auditory information is unique among sensory modalities （Kaas, 2008）. After the initial sensorineural encoding of sound at the level of the cochlea, auditory information is processed in several lower brainstem centers and eventually converges in the midbrain, at the level of the inferior colliculus （Wenstrup, 2005）, Subsequently, auditory information is transferred through the thalamus, the medial geniculate body, and then the auditory cortex （Winer et al., 2005; Razak and Fuzessery, 2010; Hackett, 2011; Lee and Sherman, 2011; Lee and Winer, 2011;展开更多
Transorbital craniocerebral injury is a relatively rare type of penetrating head injury that poses a significant threat to the ocular and cerebral structures.^([1])The clinical prognosis of transorbital craniocerebral...Transorbital craniocerebral injury is a relatively rare type of penetrating head injury that poses a significant threat to the ocular and cerebral structures.^([1])The clinical prognosis of transorbital craniocerebral injury is closely related to the size,shape,speed,nature,and trajectory of the foreign object,as well as the incidence of central nervous system damage and secondary complications.The foreign objects reported to have caused these injuries are categorized into wooden items,metallic items,^([2-8])and other materials,which penetrate the intracranial region via fi ve major pathways,including the orbital roof (OR),superior orbital fissure (SOF),inferior orbital fissure(IOF),optic canal (OC),and sphenoid wing.Herein,we present eight cases of transorbital craniocerebral injury caused by an unusual metallic foreign body.展开更多
文摘BACKGROUND:The efficacy of clinical islet transplanta-tion has been demonstrated with autografts,and although islet allografts have established insulin independence in a small number of IDDM patients,the treatment is con-founded by the necessity of central cell damage immuno-suppression,the lack of donor tissue,and recurring islet immunogenicity.These limitations underscore a need to develop therapies to serve the large population of diabetic patients.This study was designed to document central cell damage to isolated islets of Langerhans in hamsters and its prevention.METHODS:Islets were cultured at 37°C for 7-14 days after isolation,and then at 26°C for 2,4 and 7 days before addi-tional culture at 37°C for an additional 7 days.Central cell damage in the isolated islets was monitored by video-mi-croscopy and analyzed quantitatively by a computer-assis-ted image analysis system.The analysis included daily measurement of the diameter and the area of the isolated is-lets and the area of the central cell damage that developed in those islets over time during culture.Histological exami-nation and TdT-mediated dUTP-biotin nick end labeling(TUNEL)assay were used to characterize cell damage and to monitor islet function.RESULTS;Microscopic analysis showed that during the 7 to 14 days of culture at 37°C,central cell damage appeared in the larger islets with diameters greater than 200μm,which included both necrotic and apoptotic cell death.Low temperature(26°C)culture prevented central cell damage of isolated islets.The 7-day culture procedure at 26°C could inhibit most of the central cell(excluding diameters greater than 300μm)damage when the islets were re-warmed to 37°C.CONCLUSIONS:Our results indicate that central cell da-mage to isolated islets of Langerhans correlates with the size of the islets.Low temperature(26°C)culture can preventcentral cell damage to the isolated islets,and is capable to successfully precondition these islets for 37°C culture.These novel findings may help to understand the patho-physiology of early loss of islet tissue after transplantation,and may provide a new strategy to improve graft function in the clinical setting of islet transplantation.
文摘For the mammalian brain to process and decipher the rich panoply of sounds that abound in the world, nature has evolved an elegant collection of neural circuits dedicated to this task. Indeed, the complexity, variety and number of neural pathways devoted to computing auditory information is unique among sensory modalities （Kaas, 2008）. After the initial sensorineural encoding of sound at the level of the cochlea, auditory information is processed in several lower brainstem centers and eventually converges in the midbrain, at the level of the inferior colliculus （Wenstrup, 2005）, Subsequently, auditory information is transferred through the thalamus, the medial geniculate body, and then the auditory cortex （Winer et al., 2005; Razak and Fuzessery, 2010; Hackett, 2011; Lee and Sherman, 2011; Lee and Winer, 2011;
文摘Transorbital craniocerebral injury is a relatively rare type of penetrating head injury that poses a significant threat to the ocular and cerebral structures.^([1])The clinical prognosis of transorbital craniocerebral injury is closely related to the size,shape,speed,nature,and trajectory of the foreign object,as well as the incidence of central nervous system damage and secondary complications.The foreign objects reported to have caused these injuries are categorized into wooden items,metallic items,^([2-8])and other materials,which penetrate the intracranial region via fi ve major pathways,including the orbital roof (OR),superior orbital fissure (SOF),inferior orbital fissure(IOF),optic canal (OC),and sphenoid wing.Herein,we present eight cases of transorbital craniocerebral injury caused by an unusual metallic foreign body.
