Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms ...Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis, we in- duced a photochemical model of cerebral infarction in an inbred line of mice （BALB/c）. Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment. Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction, mainly in neurons and vascular endothelial cells. Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31. Moreover, hypoxic preconditioning reduced the infarct volume and improved neu- rological function in mice. These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra, which promoted angiogenesis.展开更多
Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was ...Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the animals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensiti- zation during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein kinase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits mi- graine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C activation.展开更多
The expanding development of the world economy has triggered various approaches to address the impending environmental problems,among which docximentary serves as one of the most effective and attractive ways to culti...The expanding development of the world economy has triggered various approaches to address the impending environmental problems,among which docximentary serves as one of the most effective and attractive ways to cultivate eco-harmony awareness.This article aims to probe how attitudinal resources are being distributed and what Sino-British ideologies have conveyed in the Chinese documentary,Wild China,and the British documentary,Climate Change:The Facts,under the framework of appraisal theory with the help of UAM CorpusTool 3.3.The results from this study indicate that Wild China tends to employ more dis/inclination resources to show that China is willful to collaborate with other countries for environmental protection.On the other hand,the United Kingdom(UK)tends to adopt dis/satisfaction resources to explicitly or implicitly convey their disagreement with the promotion of the economy under the cost of the environment.The appraisal resources employed by both documentaries convey the ideology of opposing humans5 over-exploitation of natural resources.The findings of this study have both theoretical and practical implications in enriching the application of appraisal theory on the analysis of ecological discourse and further encourage the world to take action in order to prevent the over-exploitation of natural resources.展开更多
This article discusses about the cultivation of foreign language talents,through which it can be appreciated that the emphasis is to be laid on improving their comprehensive qualities.Only in this way can foreign lang...This article discusses about the cultivation of foreign language talents,through which it can be appreciated that the emphasis is to be laid on improving their comprehensive qualities.Only in this way can foreign language talents adapt to the needs of the market,integrate into the ranks of technical personnel in the field of engineering,and be warmly welcomed by employers or employing units.Nevertheless,in order to achieve this aim,three factors should be overcome to avoid the hindrance faced by technical colleges and universities from cultivating foreign language talents with comprehensive qualities.This article probes into the three negative factors:first,students are not fluent in their mother tongue;second,foreign language majors lack basic knowledge of science and technology so much so that they are not able to do well in such translation;third,they lack the ability to perform simultaneous interpretation Simultaneous interpreting.In regard to those factors,this article then provides several suggestions as countermeasures to those three negative factors,so as to cultivate talents that can satisfy the needs of the market.展开更多
BACKGROUND:It has been shown that although brain does not contain lining endothelial lymphatic vessel,it has lymphatic drain.Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducin...BACKGROUND:It has been shown that although brain does not contain lining endothelial lymphatic vessel,it has lymphatic drain.Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system;however,the significance of lymphatic drain and the effect on cerebral edema remains unclear.OBJECTIVE:To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats.DESIGN:Randomized controlled animal study.SETTING:Institute of Cerebral Microcirculation of Taishan Medical College and Department of Neurology of Affiliated Hospital.MATERIALS:A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study.Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups:general observation group(n=12),light microscopic observation group(n=21)and electronic microscopic observation group(n=14).The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup.Sixteen rats were used for observing the effect of cerebral lymphatic block on cortical evoked potential,in which the animals were randomly divided into sham-operation group(n=6)and cerebral lymphatic block group(n=10).METHODS:The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003.Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition.Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels,respectively,and then lymph node was removed so as to establish cerebral lymphatic drain disorder models.Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes,and other operations were as the same as those in cerebral lymphatic block group.Morphological changes of the brain and alterations of latency of cortical evoked potential were detected on the 1st,2nd,3rd,5th,7th,10th and 15th days after operation under general,light microscope and electronic microscope observations.MAIN OUTCOME MEASURES:①Cerebral morphological changes;②latent changes of cortical evoked potential.RESULTS:A total of 63 rats were involved in the final analysis.①Cerebral morphological changes:General observation showed that,for cerebral lymphatic block rats,the surface of brain was pale and full,and cerebral gyrus was wide and flattened sulci after cerebral lymphatic block;and cerebral tissue space prolongation,increased interstitial fluid,neuronal degeneration and necrosis,diffused phagocytes and satellitosis were observed under light microscope.Neuronal swell and necrosis,glial cell swell,apparent subcellular changes such as mitochondron were observed under electronic microscope.②Latent changes of cortical evoked potential:As compared with sham-operation control group,latency of cortical evoked potential in cerebral lymphatic blockage group prolonged on the 5th day and 7th day after cerebral lymphatic block[(6.28±0.23),(6.97±0.35)ms;(6.23±0.22),(7.12±0.20)ms;P<0.01].CONCLUSION:①Cerebral lymphatic block plays an important role in cerebral morphology,and may result in abnormality of sensitive impulse conduction and prolong latency of cortical evoked potential.②Examination of cortical evoked potential is easy and convenient,so it is regarded as a key index for lymphatic disturbed cerebral injury.展开更多
The diverse functions of phosphoenolpyruvate carboxylase （PEPCase; EC 4.1.1.31） in C3 plants are not as well understood as in C4 plants. To investigate the functions of PEPCase in C3 plants, rapeseed （Brassica napu...The diverse functions of phosphoenolpyruvate carboxylase （PEPCase; EC 4.1.1.31） in C3 plants are not as well understood as in C4 plants. To investigate the functions of PEPCase in C3 plants, rapeseed （Brassica napus L.） PEPCase gene （referred to as BNPE15） was silenced by the RNA interference （RNAi） technique. Under normal growth conditions, no significant difference in lipid content and fatty acid composition were found between wild-type （WT） and transgenic rapeseed plants. However, when these plants were subjected to osmotic stress induced by osmoticum polyethylene glycol （PEG-6000）, membrane permeability and membrane lipid peroxidization in roots and leaves of transgenic plants were higher than those of WT plants. It suggested that transgenic plants are more susceptible to osmotic stress than WT plants. Taken together, the results showed that the suppression of PEPCase by RNAi leads to susceptibility to osmotic stress in rapeseed, and PEPCase is involved in the response of C3 plants to environmental stress.展开更多
Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalitie...Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalities underlying the differences in ol-factory dysfunction between EOD and LOD remain unclear.Objective:The aim of this study was to compare the functional connectivity(FC)patterns of olfactory regions between EOD patients and LOD patients and examine their relationship with cognitive function.Methods:One hundred and five patients with EOD,101 patients with LOD and 160 normal controls(NCs)were recruited for the present study.Participants underwent clinical assessment,olfactory testing,cognitive assessments,and magnetic resonance imaging.Eight regions of the primary and secondary olfactory regions were selected to investigate olfactory FC.Results:Patients with LOD exhibited decreased odor identification(OI)compared with patients with EOD and NCs.The LOD group exhibited decreased FC compared with the EOD and NC groups when primary and secondary olfactory regions were selected as the regions of interest(the piriform cortex,lateral entorhinal cortex,and orbital-frontal cortex).Additionally,these abnormal olfactory FCs were associated with decreased cognitive function scores and OI,and the FC between the left orbital-frontal cortex and left amygdala was a partial mediator of the relationship between global cognitive scores and OI.Conclusion:Overall,patients with LOD exhibited decreased FC in both the primary and secondary olfactory cortices compared with patients with EOD,and abnormal olfactory FC was associated with OI dysfunction and cognitive impairment.The FC between the orbital-frontal cortex and amygdala mediated the relationship between global cognitive function and OI.展开更多
基金supported by the National Natural Science Foundation of China,No.30870854the Natural Science Foundation of Beijing,No.7111003the Natural Science Foundation of Shandong Province,No.ZR2010HM029
文摘Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis, we in- duced a photochemical model of cerebral infarction in an inbred line of mice （BALB/c）. Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment. Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction, mainly in neurons and vascular endothelial cells. Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31. Moreover, hypoxic preconditioning reduced the infarct volume and improved neu- rological function in mice. These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra, which promoted angiogenesis.
基金financially sponsored by the Natural Science Foundation of Shandong Province,No.ZR2012HQ014a grant from the Science and Technology Plan Program of Universities in Shandong Province,No.J10LF14
文摘Peripheral and central sensitizations are phenomena that occur during migraine. The role of gabapentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the animals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensiti- zation during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein kinase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits mi- graine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C activation.
基金the Fundamental Research Funds for the Central Universities of Central South University,(Grant Number:1053320210469).
文摘The expanding development of the world economy has triggered various approaches to address the impending environmental problems,among which docximentary serves as one of the most effective and attractive ways to cultivate eco-harmony awareness.This article aims to probe how attitudinal resources are being distributed and what Sino-British ideologies have conveyed in the Chinese documentary,Wild China,and the British documentary,Climate Change:The Facts,under the framework of appraisal theory with the help of UAM CorpusTool 3.3.The results from this study indicate that Wild China tends to employ more dis/inclination resources to show that China is willful to collaborate with other countries for environmental protection.On the other hand,the United Kingdom(UK)tends to adopt dis/satisfaction resources to explicitly or implicitly convey their disagreement with the promotion of the economy under the cost of the environment.The appraisal resources employed by both documentaries convey the ideology of opposing humans5 over-exploitation of natural resources.The findings of this study have both theoretical and practical implications in enriching the application of appraisal theory on the analysis of ecological discourse and further encourage the world to take action in order to prevent the over-exploitation of natural resources.
文摘This article discusses about the cultivation of foreign language talents,through which it can be appreciated that the emphasis is to be laid on improving their comprehensive qualities.Only in this way can foreign language talents adapt to the needs of the market,integrate into the ranks of technical personnel in the field of engineering,and be warmly welcomed by employers or employing units.Nevertheless,in order to achieve this aim,three factors should be overcome to avoid the hindrance faced by technical colleges and universities from cultivating foreign language talents with comprehensive qualities.This article probes into the three negative factors:first,students are not fluent in their mother tongue;second,foreign language majors lack basic knowledge of science and technology so much so that they are not able to do well in such translation;third,they lack the ability to perform simultaneous interpretation Simultaneous interpreting.In regard to those factors,this article then provides several suggestions as countermeasures to those three negative factors,so as to cultivate talents that can satisfy the needs of the market.
文摘BACKGROUND:It has been shown that although brain does not contain lining endothelial lymphatic vessel,it has lymphatic drain.Anterior lymphatic system of lymphatic vessel in brain tissue plays a key role in introducing brain interstitial fluid to lymphatic system;however,the significance of lymphatic drain and the effect on cerebral edema remains unclear.OBJECTIVE:To investigate the effect of cerebral lymphatic block on cerebral morphology and cortical evoked potential in rats.DESIGN:Randomized controlled animal study.SETTING:Institute of Cerebral Microcirculation of Taishan Medical College and Department of Neurology of Affiliated Hospital.MATERIALS:A total of 63 healthy adult male Wistar rats weighing 300-350 g were selected in this study.Forty-seven rats were used for the morphological observation induced by lymphatic drain and randomly divided into three groups:general observation group(n=12),light microscopic observation group(n=21)and electronic microscopic observation group(n=14).The rats in each group were divided into cerebral lymphatic block subgroup and sham-operation control subgroup.Sixteen rats were used for observing the effect of cerebral lymphatic block on cortical evoked potential,in which the animals were randomly divided into sham-operation group(n=6)and cerebral lymphatic block group(n=10).METHODS:The experiment was carried out in the Institute of Cerebral Microcirculation of Taishan Medical College from January to August 2003.Rats in cerebral lymphatic block group were anesthetized and separated bilateral superficial and deep cervical lymph nodes under sterile condition.Superior and inferior boarders of lymph nodes were ligated the inputting and outputting channels,respectively,and then lymph node was removed so as to establish cerebral lymphatic drain disorder models.Rats in sham-operation control group were not ligated the lymphatic vessel and removed lymph nodes,and other operations were as the same as those in cerebral lymphatic block group.Morphological changes of the brain and alterations of latency of cortical evoked potential were detected on the 1st,2nd,3rd,5th,7th,10th and 15th days after operation under general,light microscope and electronic microscope observations.MAIN OUTCOME MEASURES:①Cerebral morphological changes;②latent changes of cortical evoked potential.RESULTS:A total of 63 rats were involved in the final analysis.①Cerebral morphological changes:General observation showed that,for cerebral lymphatic block rats,the surface of brain was pale and full,and cerebral gyrus was wide and flattened sulci after cerebral lymphatic block;and cerebral tissue space prolongation,increased interstitial fluid,neuronal degeneration and necrosis,diffused phagocytes and satellitosis were observed under light microscope.Neuronal swell and necrosis,glial cell swell,apparent subcellular changes such as mitochondron were observed under electronic microscope.②Latent changes of cortical evoked potential:As compared with sham-operation control group,latency of cortical evoked potential in cerebral lymphatic blockage group prolonged on the 5th day and 7th day after cerebral lymphatic block[(6.28±0.23),(6.97±0.35)ms;(6.23±0.22),(7.12±0.20)ms;P<0.01].CONCLUSION:①Cerebral lymphatic block plays an important role in cerebral morphology,and may result in abnormality of sensitive impulse conduction and prolong latency of cortical evoked potential.②Examination of cortical evoked potential is easy and convenient,so it is regarded as a key index for lymphatic disturbed cerebral injury.
基金supported by the National Natural Science Foundation of China(30770224)
文摘The diverse functions of phosphoenolpyruvate carboxylase （PEPCase; EC 4.1.1.31） in C3 plants are not as well understood as in C4 plants. To investigate the functions of PEPCase in C3 plants, rapeseed （Brassica napus L.） PEPCase gene （referred to as BNPE15） was silenced by the RNA interference （RNAi） technique. Under normal growth conditions, no significant difference in lipid content and fatty acid composition were found between wild-type （WT） and transgenic rapeseed plants. However, when these plants were subjected to osmotic stress induced by osmoticum polyethylene glycol （PEG-6000）, membrane permeability and membrane lipid peroxidization in roots and leaves of transgenic plants were higher than those of WT plants. It suggested that transgenic plants are more susceptible to osmotic stress than WT plants. Taken together, the results showed that the suppression of PEPCase by RNAi leads to susceptibility to osmotic stress in rapeseed, and PEPCase is involved in the response of C3 plants to environmental stress.
基金supported by a grant from the National Natu-ral Science Foundation of China (nos 82171533,82101508)Medical Scientific Technology Research Foundation of Guangdong Province of China (no.A2020446)the Key Laboratory for Innovation Platform Plan,the Science and Technology Program of Guangzhou,China,the Science and Technology Plan Project of Guangdong Province (no.2019B030316001).
文摘Background:Late-onset depression(LOD)and early-onset depression(EOD)exhibit different pathological mechanisms and clinical phenotypes,including different extents of olfactory dysfunction.However,the brain abnormalities underlying the differences in ol-factory dysfunction between EOD and LOD remain unclear.Objective:The aim of this study was to compare the functional connectivity(FC)patterns of olfactory regions between EOD patients and LOD patients and examine their relationship with cognitive function.Methods:One hundred and five patients with EOD,101 patients with LOD and 160 normal controls(NCs)were recruited for the present study.Participants underwent clinical assessment,olfactory testing,cognitive assessments,and magnetic resonance imaging.Eight regions of the primary and secondary olfactory regions were selected to investigate olfactory FC.Results:Patients with LOD exhibited decreased odor identification(OI)compared with patients with EOD and NCs.The LOD group exhibited decreased FC compared with the EOD and NC groups when primary and secondary olfactory regions were selected as the regions of interest(the piriform cortex,lateral entorhinal cortex,and orbital-frontal cortex).Additionally,these abnormal olfactory FCs were associated with decreased cognitive function scores and OI,and the FC between the left orbital-frontal cortex and left amygdala was a partial mediator of the relationship between global cognitive scores and OI.Conclusion:Overall,patients with LOD exhibited decreased FC in both the primary and secondary olfactory cortices compared with patients with EOD,and abnormal olfactory FC was associated with OI dysfunction and cognitive impairment.The FC between the orbital-frontal cortex and amygdala mediated the relationship between global cognitive function and OI.
