AIM： To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 （TRPM7） in the human gastrointestinal （GI） tract. METHODS： Conventional microel...AIM： To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 （TRPM7） in the human gastrointestinal （GI） tract. METHODS： Conventional microelectrode techniques were used to record intracellular electrical responses from human GI smooth muscle tissue. Immunohistochemistry was used to identify TRPM7 channels in interstitial cells of Cajat （ICCs）. RESULTS： The human GI tract generated slow electrical waves and had ICCs which functioned as pacemak er cells. Flufenamic acid, a nonselective cation channel blocker, and 2-APB （2-aminoethoxydiphenyl borate） and La3＋, TRPM7 channel blockers, inhibited the slowwaves. Also, TRPM7 channels were expressed in ICCs in human tissue. CONCLUSION： These results suggest that the human GI tract generates slow waves and that TRPM7 channels expressed in the ICCs may be involved in the gen- eration of the slow waves.展开更多
The mixed lineage kinase domain-like(MLKL)protein is a key factor in tumor necrosis factor-induced necroptosis.Recent studies on necroptosis execution revealed a commitment role of MLKL in membrane disruption.However,...The mixed lineage kinase domain-like(MLKL)protein is a key factor in tumor necrosis factor-induced necroptosis.Recent studies on necroptosis execution revealed a commitment role of MLKL in membrane disruption.However,our knowledge of how MLKL functions on membrane remains very limited.Here we demonstrate that MLKL forms cation channels that are permeable preferential y to Mg2+rather than Ca2+in the presence of Na+and K+.Moreover,the N-terminal domain containing six helices(H1-H6)is sufficient to form channels.Using the substituted cysteine accessibility method,we further determine that helix H1,H2,H3,H5 and H6 are transmembrane segments,while H4 is located in the cytoplasm.Finally,MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel activity.The Mg2+-preferred permeability and five transmembrane segment topology distinguish MLKL from previously identified Mg2+-permeable channels and thus establish MLKL as a novel class of cation channels.展开更多
OBJECTIVE To investigate how MLKL functions on the membrane and explore its electrophysiological characters and structure.METHODS The full-length human MLKL were expressed in SF21 cells and purified using glutathione-...OBJECTIVE To investigate how MLKL functions on the membrane and explore its electrophysiological characters and structure.METHODS The full-length human MLKL were expressed in SF21 cells and purified using glutathione-sepharose affinity chromatography.The currents of purified MLKL proteins were recorded in avoltage-clamp mode using a Warner BC-535 bilayer clamp amplifier.The currents were digitized using p CLAMP 10.2 software.HEK293 cells were cultured and transfected with MLKL plasmid.Cell viability was examined using the Cell Titer-Glo Luminescent Cell Viability Assay kit.RESULT MLKL forms cation channels that are permeable preferentially to Mg2+rather than Ca2+in the presence of Na+and K+.Moreover,each MLKL monomer contains five transmembrane helices:H1,H2,H3,H5 and H6 of the N-terminal domain which is sufficient to form channels.Finally,MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel activity.展开更多
Aim： To investigate the expression and distribution of the members of the transient receptor potential （TRP） channel members of TRP melastatin （TRPM） and TRP vanilloid （TRPV） subfamilies in rat prostatic tissue...Aim： To investigate the expression and distribution of the members of the transient receptor potential （TRP） channel members of TRP melastatin （TRPM） and TRP vanilloid （TRPV） subfamilies in rat prostatic tissue. Methods： Prostate tissue was obtained from male Sprague-Dawley rats. Reverse transcription polymerase chain reaction （RT-PCR） and quantitative real-time polymerase chain reaction （PCR） were used to check the expression of all TRPM and TRPV channel members with specific primers. Immunohistochemistry staining for TRPM8 and TRPV1 were also performed in rat tissues. Results： TRPM2, TRPM3, TRPM4, TRPM6, TRPM7, TRPMS, TRPV2 and TRPV4 mRNA were detected in all rat prostatic tissues. Very weak signals for TRPM1, TRPVI and TRPV3 were also detected. The mRNA of TRPM5, TRPV5 and TRPV6 were not detected in all RT-PCR experiments. Quantitative real-time RT-PCR showed that TRPM2, TRPM3, TRPM4, TRPMS, TRPV2 and TRPV4 were the most abundantly expressed TRPM and TRPV subtypes, respectively. Fluorescence immunohistochemistry indicated that TRPM8 and TRPV 1 are highly expressed in both epithelial and smooth muscle cells. Conclusion： Our results demonstrate that mRNA or protein for TRPM1, TRPM2, TRPM3, TRPM4, TRPM6, TRPM7, TRPMS, TRPV1, TRPV2, TRPV3 and TRPV4 exist in rat prostatic tissue. The data presented here assists in elucidating the physiological function of TRPM and TRPV channels.展开更多
To investigate the mechanisms of microwave induced pacemaker cell injuries, Wistar rats and the primary pacemaker cells of newborn Wistar rats were exposed to microwave at average power density of 50 mW/cm2. Slower sp...To investigate the mechanisms of microwave induced pacemaker cell injuries, Wistar rats and the primary pacemaker cells of newborn Wistar rats were exposed to microwave at average power density of 50 mW/cm2. Slower spontaneous beating rate, intercellular Ca2＋ aggregation and cell membrane perforation were detected immediately after the exposure. Moreover, hyperpolarizationactivated cyclic nucleotide-gated cation channel 4 （HCN4） was down-regulated immediately after the exposure and up-regulated at 12 h after the exposure. In the sinoatrial node （SAN） of the rats,展开更多
The transient receptor potential cation channel subfamily V member 1（TRPV1） provides the sensation of pain（nociception）. However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whe...The transient receptor potential cation channel subfamily V member 1（TRPV1） provides the sensation of pain（nociception）. However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517（300 mg/kg）, a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immunofluorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clusters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve.展开更多
Molecular dynamics simulation was utilized to investigate the transport and adsorption of chloride in the nanopore of calcium aluminosilicate hydrate(C-A-S-H)with associated cation types of Ca,Mg,Na and K.The local io...Molecular dynamics simulation was utilized to investigate the transport and adsorption of chloride in the nanopore of calcium aluminosilicate hydrate(C-A-S-H)with associated cation types of Ca,Mg,Na and K.The local ionic structure,atomic dynamics and bond stability were analyzed to elucidate the interaction between cations and chloride ions.The results show that interfacial chloride is absorbed through the ion pairing formation in the vicinity of C-A-S-H substrate.Interfacial cations can simultaneously interact aluminosilicate chains,water molecules and Cl^(-)ions,which restrict the motion of interfacial Cl^(-)ions.Pore solution chloride can be immobilized through the solvation effect of cations.Cations along with their hydration shell can connect to neighboring Cl^(-)ions to decrease their mobility.Owing to the varied ionic chemistry,cations show different interaction strength with neighboring water molecules and anions,which determines the chloride transport behavior in the nanopore of C-A-S-H.The chloride immobilization capacity of C-A-S-H nanopore with different associated cations is listed in following order:Mg^(2+)Ca^(2+)<Na^(+)≈K^(+),which agrees reasonably with previous experiments.展开更多
BACKGROUND Transient receptor potential vanilloid-1(TRPV1),a nonselective cation channel,is activated by capsaicin,a pungent ingredient of hot pepper.Previous studies have suggested a link between obesity and capsaici...BACKGROUND Transient receptor potential vanilloid-1(TRPV1),a nonselective cation channel,is activated by capsaicin,a pungent ingredient of hot pepper.Previous studies have suggested a link between obesity and capsaicin-associated pathways,and activation of TRPV1 may provide an alternative approach for obesity treatment.However,data on the TRPV1 distribution in human gastric mucosa are limited,and the degree of TRPV1 distribution in the gastric and duodenal mucosal cells of obese people in comparison with normal-weight individuals is unknown.AIM To clarify gastric and duodenal mucosal expression of TRPV1 in humans and compare TRPV1 expression in obese and healthy individuals.METHODS Forty-six patients with a body mass index(BMI)of>40 kg/m^(2) and 20 patients with a BMI between 18-25 kg/m^(2) were included.Simultaneous biopsies from the fundus,antrum,and duodenum tissues were obtained from subjects between the ages of 18 and 65 who underwent esophagogastroduodenoscopy.Age,sex,history of alcohol and cigarette consumption,and past medical history regarding chronic diseases and medications were accessed from patient charts and were analyzed accordingly.Evaluation with anti-TRPV1 antibody was performed separately according to cell types in the fundus,antrum,and duodenum tissues using an immunoreactivity score.Data were analyzed using SPSS 17.0.RESULTS TRPV1 expression was higher in the stomach than in the duodenum and was predominantly found in parietal and chief cells of the fundus and mucous and foveolar cells of the antrum.Unlike foveolar cells in the antrum,TRPV1 was relatively low in foveolar cells in the fundus(4.92±0.49 vs 0.48±0.16,P<0.01,Mann-Whitney U test).Additionally,the mucous cells in the duodenum also had low levels of TRPV1 compared to mucous cells in the antrum(1.33±0.31 vs 2.95±0.46,P<0.01,Mann-Whitney U test).TRPV1 expression levels of different cell types in the fundus,antrum,and duodenum tissues of the morbidly obese group were similar to those of the control group.Staining with TRPV1 in fundus chief cells and antrum and duodenum mucous cells was higher in patients aged≥45 years than in patients<45 years(3.03±0.42,4.37±0.76,2.28±0.55 vs 1.9±0.46,1.58±0.44,0.37±0.18,P=0.03,P<0.01,P<0.01,respectively,Mann-Whitney U test).The mean staining levels of TRPV1 in duodenal mucous cells in patients with diabetes and hypertension were higher than those in patients without diabetes and hypertension(diabetes:2.11±0.67 vs 1.02±0.34,P=0.04;hypertension:2.42±0.75 vs 1.02±0.33,P<0.01 Mann-Whitney U test).CONCLUSION The expression of TRPV1 is unchanged in the gastroduodenal mucosa of morbidly obese patients demonstrating that drugs targeting TRPV1 may be effective in these patients.展开更多
Simple power analysis is the most devastating attack on the security of elliptic curve scalar multiplication and can probably retrieve the secret key. In this paper,we analyze the formulas of point doubling and additi...Simple power analysis is the most devastating attack on the security of elliptic curve scalar multiplication and can probably retrieve the secret key. In this paper,we analyze the formulas of point doubling and addition on Jacobi-quartic Curve in projective coordination. In addition,a fast and secure side-channel atomic scalar multiplication algorithm is proposed using the side-channel atomic block. Compared with the previous methods,the new algorithm is more efficient. For 192 bits scalar using NAF recoding,the efficiency of the new algorithm is increased by about 6.7%～23% if S/M=0.8 or 12.7%～33.2% if S/M=0.6.展开更多
基金Supported by The Creative Research Initiative Center for Bio-Artificial Muscle of the Ministry of Education,Science and Technology (MEST) in Korea
文摘AIM： To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 （TRPM7） in the human gastrointestinal （GI） tract. METHODS： Conventional microelectrode techniques were used to record intracellular electrical responses from human GI smooth muscle tissue. Immunohistochemistry was used to identify TRPM7 channels in interstitial cells of Cajat （ICCs）. RESULTS： The human GI tract generated slow electrical waves and had ICCs which functioned as pacemak er cells. Flufenamic acid, a nonselective cation channel blocker, and 2-APB （2-aminoethoxydiphenyl borate） and La3＋, TRPM7 channel blockers, inhibited the slowwaves. Also, TRPM7 channels were expressed in ICCs in human tissue. CONCLUSION： These results suggest that the human GI tract generates slow waves and that TRPM7 channels expressed in the ICCs may be involved in the gen- eration of the slow waves.
文摘The mixed lineage kinase domain-like(MLKL)protein is a key factor in tumor necrosis factor-induced necroptosis.Recent studies on necroptosis execution revealed a commitment role of MLKL in membrane disruption.However,our knowledge of how MLKL functions on membrane remains very limited.Here we demonstrate that MLKL forms cation channels that are permeable preferential y to Mg2+rather than Ca2+in the presence of Na+and K+.Moreover,the N-terminal domain containing six helices(H1-H6)is sufficient to form channels.Using the substituted cysteine accessibility method,we further determine that helix H1,H2,H3,H5 and H6 are transmembrane segments,while H4 is located in the cytoplasm.Finally,MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel activity.The Mg2+-preferred permeability and five transmembrane segment topology distinguish MLKL from previously identified Mg2+-permeable channels and thus establish MLKL as a novel class of cation channels.
基金the National Natural Science Foundation of China(No.30470559,30330230,30240059)the National Basic Research Development Program(973)of China(No.2007CB512501)Beijing Natural Science Foundation(No.7052039)
文摘Dorsal root ganglion(DRG)neurons have peripheral terminals in skin,muscle,and other peripheral tissues,andcentral
基金supported by State Key Program of Basic Research of China(2013CB910604)National Natural Science Foundation of China(61327014,61175103,61433017 and31571427)the External Cooperation Program of BIC,Chinese Academy of Sciences(1536631KYSB20130003)
文摘OBJECTIVE To investigate how MLKL functions on the membrane and explore its electrophysiological characters and structure.METHODS The full-length human MLKL were expressed in SF21 cells and purified using glutathione-sepharose affinity chromatography.The currents of purified MLKL proteins were recorded in avoltage-clamp mode using a Warner BC-535 bilayer clamp amplifier.The currents were digitized using p CLAMP 10.2 software.HEK293 cells were cultured and transfected with MLKL plasmid.Cell viability was examined using the Cell Titer-Glo Luminescent Cell Viability Assay kit.RESULT MLKL forms cation channels that are permeable preferentially to Mg2+rather than Ca2+in the presence of Na+and K+.Moreover,each MLKL monomer contains five transmembrane helices:H1,H2,H3,H5 and H6 of the N-terminal domain which is sufficient to form channels.Finally,MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel activity.
文摘Aim： To investigate the expression and distribution of the members of the transient receptor potential （TRP） channel members of TRP melastatin （TRPM） and TRP vanilloid （TRPV） subfamilies in rat prostatic tissue. Methods： Prostate tissue was obtained from male Sprague-Dawley rats. Reverse transcription polymerase chain reaction （RT-PCR） and quantitative real-time polymerase chain reaction （PCR） were used to check the expression of all TRPM and TRPV channel members with specific primers. Immunohistochemistry staining for TRPM8 and TRPV1 were also performed in rat tissues. Results： TRPM2, TRPM3, TRPM4, TRPM6, TRPM7, TRPMS, TRPV2 and TRPV4 mRNA were detected in all rat prostatic tissues. Very weak signals for TRPM1, TRPVI and TRPV3 were also detected. The mRNA of TRPM5, TRPV5 and TRPV6 were not detected in all RT-PCR experiments. Quantitative real-time RT-PCR showed that TRPM2, TRPM3, TRPM4, TRPMS, TRPV2 and TRPV4 were the most abundantly expressed TRPM and TRPV subtypes, respectively. Fluorescence immunohistochemistry indicated that TRPM8 and TRPV 1 are highly expressed in both epithelial and smooth muscle cells. Conclusion： Our results demonstrate that mRNA or protein for TRPM1, TRPM2, TRPM3, TRPM4, TRPM6, TRPM7, TRPMS, TRPV1, TRPV2, TRPV3 and TRPV4 exist in rat prostatic tissue. The data presented here assists in elucidating the physiological function of TRPM and TRPV channels.
文摘To investigate the mechanisms of microwave induced pacemaker cell injuries, Wistar rats and the primary pacemaker cells of newborn Wistar rats were exposed to microwave at average power density of 50 mW/cm2. Slower spontaneous beating rate, intercellular Ca2＋ aggregation and cell membrane perforation were detected immediately after the exposure. Moreover, hyperpolarizationactivated cyclic nucleotide-gated cation channel 4 （HCN4） was down-regulated immediately after the exposure and up-regulated at 12 h after the exposure. In the sinoatrial node （SAN） of the rats,
基金supported by the National Natural Science Foundation of China,No.81171178the Natural Science Foundation of Shanxi Province in China,No.2012011036-3Scientific Research Foundation of Shanxi Province of China for the Returned Overseas Chinese Scholars,No.2013011054-2
文摘The transient receptor potential cation channel subfamily V member 1（TRPV1） provides the sensation of pain（nociception）. However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517（300 mg/kg）, a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immunofluorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clusters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve.
基金Funded by the National Natural Science Foundation of China(Nos.52008002,U21A20149,U2006224 and 51978352)the Open Foundation of the State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology)(No.SYSJJ2022-22)Anhui Province Engineering Laboratory of Advanced Building Materials(No.JZCL2202ZR)。
文摘Molecular dynamics simulation was utilized to investigate the transport and adsorption of chloride in the nanopore of calcium aluminosilicate hydrate(C-A-S-H)with associated cation types of Ca,Mg,Na and K.The local ionic structure,atomic dynamics and bond stability were analyzed to elucidate the interaction between cations and chloride ions.The results show that interfacial chloride is absorbed through the ion pairing formation in the vicinity of C-A-S-H substrate.Interfacial cations can simultaneously interact aluminosilicate chains,water molecules and Cl^(-)ions,which restrict the motion of interfacial Cl^(-)ions.Pore solution chloride can be immobilized through the solvation effect of cations.Cations along with their hydration shell can connect to neighboring Cl^(-)ions to decrease their mobility.Owing to the varied ionic chemistry,cations show different interaction strength with neighboring water molecules and anions,which determines the chloride transport behavior in the nanopore of C-A-S-H.The chloride immobilization capacity of C-A-S-H nanopore with different associated cations is listed in following order:Mg^(2+)Ca^(2+)<Na^(+)≈K^(+),which agrees reasonably with previous experiments.
文摘BACKGROUND Transient receptor potential vanilloid-1(TRPV1),a nonselective cation channel,is activated by capsaicin,a pungent ingredient of hot pepper.Previous studies have suggested a link between obesity and capsaicin-associated pathways,and activation of TRPV1 may provide an alternative approach for obesity treatment.However,data on the TRPV1 distribution in human gastric mucosa are limited,and the degree of TRPV1 distribution in the gastric and duodenal mucosal cells of obese people in comparison with normal-weight individuals is unknown.AIM To clarify gastric and duodenal mucosal expression of TRPV1 in humans and compare TRPV1 expression in obese and healthy individuals.METHODS Forty-six patients with a body mass index(BMI)of>40 kg/m^(2) and 20 patients with a BMI between 18-25 kg/m^(2) were included.Simultaneous biopsies from the fundus,antrum,and duodenum tissues were obtained from subjects between the ages of 18 and 65 who underwent esophagogastroduodenoscopy.Age,sex,history of alcohol and cigarette consumption,and past medical history regarding chronic diseases and medications were accessed from patient charts and were analyzed accordingly.Evaluation with anti-TRPV1 antibody was performed separately according to cell types in the fundus,antrum,and duodenum tissues using an immunoreactivity score.Data were analyzed using SPSS 17.0.RESULTS TRPV1 expression was higher in the stomach than in the duodenum and was predominantly found in parietal and chief cells of the fundus and mucous and foveolar cells of the antrum.Unlike foveolar cells in the antrum,TRPV1 was relatively low in foveolar cells in the fundus(4.92±0.49 vs 0.48±0.16,P<0.01,Mann-Whitney U test).Additionally,the mucous cells in the duodenum also had low levels of TRPV1 compared to mucous cells in the antrum(1.33±0.31 vs 2.95±0.46,P<0.01,Mann-Whitney U test).TRPV1 expression levels of different cell types in the fundus,antrum,and duodenum tissues of the morbidly obese group were similar to those of the control group.Staining with TRPV1 in fundus chief cells and antrum and duodenum mucous cells was higher in patients aged≥45 years than in patients<45 years(3.03±0.42,4.37±0.76,2.28±0.55 vs 1.9±0.46,1.58±0.44,0.37±0.18,P=0.03,P<0.01,P<0.01,respectively,Mann-Whitney U test).The mean staining levels of TRPV1 in duodenal mucous cells in patients with diabetes and hypertension were higher than those in patients without diabetes and hypertension(diabetes:2.11±0.67 vs 1.02±0.34,P=0.04;hypertension:2.42±0.75 vs 1.02±0.33,P<0.01 Mann-Whitney U test).CONCLUSION The expression of TRPV1 is unchanged in the gastroduodenal mucosa of morbidly obese patients demonstrating that drugs targeting TRPV1 may be effective in these patients.
基金sponsored and financial supported by National Natural Science Foundation of China (NSFC), grant No.61003121Sichuan Province High Technology Program under No.2009CD00014
文摘Simple power analysis is the most devastating attack on the security of elliptic curve scalar multiplication and can probably retrieve the secret key. In this paper,we analyze the formulas of point doubling and addition on Jacobi-quartic Curve in projective coordination. In addition,a fast and secure side-channel atomic scalar multiplication algorithm is proposed using the side-channel atomic block. Compared with the previous methods,the new algorithm is more efficient. For 192 bits scalar using NAF recoding,the efficiency of the new algorithm is increased by about 6.7%～23% if S/M=0.8 or 12.7%～33.2% if S/M=0.6.
