1.Two-way concentration-dependent effect of H2O2 on I(Kur) and I(Ca,L) in human atrial myocytes..
Guang-Wei ZHANG ; Tian-Xiang GU ; Chun WANG ; Lei YU ; Ti WEN
Acta Physiologica Sinica 2008;60(6):695-703
It has been shown that oxidative stress correlates with atrial fibrillation (AF). The purpose of the present study was to investigate the effects of reactive oxygen species (ROS) on the electrophysiological activity of human atrial myocytes. Right atrial appendages were obtained from patients with AF (AF group, n=12) and without AF (non-AF group, n=12). Single human atrial myocytes were isolated through enzymatic dissociation with type XXIV protease and type V collagenase, then divided into three subgroups: control group (n=12), H2O2 group (0.1, 0.2, 0.5, 0.75, 1, 2, 5, 10 mumol/L, n=7 at each concentration) and vitamin C (antioxidant) group (1 mumol/L, n=7). Ultrarapid delayed rectifier K(+) current (I(Kur)), L-type calcium current (I(Ca,L)) and action potential duration (APD) were recorded by whole-cell patch clamp. In AF control group, the maximum current densities of I(Kur) and I(Ca,L) were significantly lower than that in non-AF control group (both P<0.05) and APD(90) was significantly shorter as well (P<0.05). In both non-AF and AF groups, H2O2 showed two-way concentration-dependent effect on I(Kur) and I(Ca,L). The maximum current densities of I(Kur) and I(Ca,L) was significantly increased at lower H2O2 concentration, but was decreased at higher H2O2 concentration. In non-AF group, 0.2 mumol/L H2O2 caused a peak increase in the maximum current identities of I(Kur) [(8.92+/-0.51) pA/pF, P<0.05] and I(Ca,L) [(9.32+/-0.67) pA/pF, P<0.05]. H2O2 at a concentration higher than 0.75 mumol/L decreased I(Kur) and I(Ca,L). When the H2O2 concentrations were 0.2, 1, 2, 5 and 10 mumol/L, APD(90) was significantly shorter compared with that in non-AF control group (P<0.05), meanwhile it had no significant difference from that in AF control group. In AF group, the peak effective concentration of H2O2 was 0.5 mumol/L, and the turning concentration was 1 mumol/L. The H2O2 concentration-current density curve in AF group was similar to that in non-AF group, but the turning point shifted to the right, indicating that the way that H2O2 acted on ion channels in AF was the same as that in non-AF, however, the sensitivity of ion channels to H2O2 was decreased in AF. Vitamin C reversed these changes induced by H2O2, and did not affect the characteristics of ion channels. H2O2-induced electrophysiological changes in human atrial myocytes were similar to atrial electrical remodeling (AER) in AF, suggesting that ROS might induce AF. Meanwhile, H2O2 also could aggravate AER in AF, contributing to the maintenance of AF. The results suggest that antioxidants might play a significant role in the prevention and treatment of AF.
Action Potentials
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Atrial Fibrillation
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physiopathology
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Calcium
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physiology
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Calcium Channels, L-Type
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physiology
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Delayed Rectifier Potassium Channels
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physiology
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Heart Atria
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cytology
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Humans
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Hydrogen Peroxide
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chemistry
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Myocytes, Cardiac
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physiology
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Patch-Clamp Techniques
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Potassium
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physiology
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Reactive Oxygen Species
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chemistry
2.Effects of post material on stress distribution in dentine.
Xiang-tao CHEN ; Xiao-na LI ; Zhen-qun GUAN ; Xiao-guang LIU ; Yuan-xian GU
Chinese Journal of Stomatology 2004;39(4):302-305
OBJECTIVETo investigate stress distribution of different material restored post-cores in dentine and provide a theoretical guidance for clinical use.
METHODSA three-dimensional finite element model of maxillary central incisor restored with post-core and PFM crown was constructed by SCT scan technology. Based on this model, stress distribution in dentine was analyzed before and after post-core restorations with 6 different materials, including cast Ni-Cr alloy, cast titanium alloy, cast gold alloy, glass fiber reinforced composite, polythene fiber reinforced composite, and common composite resin.
RESULTSWhen the tooth was restored with cast Ni-Cr alloy post and PFM crown, the maximum tensile stress and Von Mises stress in dentin at post apex increased 152% and 162% respectively, compared with a tooth restored only with PFM crown. If polythene fiber reinforced composite was used as post material, the stress distribution did not significantly change. When the other materials were used for the post, the stress distribution changed greatly. The elastic modulus of post-core materials affected the stress distribution pattern in dentine.
CONCLUSIONThe materials with elastic modulus similar to that of dentin, such as polythene fiber reinforced composite, may be suitable for post restoration.
Chromium Alloys ; Dental Materials ; Dental Restoration, Permanent ; Dental Stress Analysis ; methods ; Dentin ; Finite Element Analysis ; Humans ; Incisor ; physiology ; Materials Testing ; Post and Core Technique ; Tensile Strength
3.Staging Based Strategies and Practice for Prostate Cancer.
Zhi-qiang CHEN ; Shu-sheng WANG ; Zun-guang BAI ; Zhao-hui WANG ; Li-guo LV ; Chi-ming GU ; Song-tao XIANG ; Rui-xin DAI ; Shou-lun ZHU
Chinese Journal of Integrated Traditional and Western Medicine 2016;36(6):749-752
Authors raised that staging based strategies and practice of integrative medicine (IM) by combining syndrome typing and disease identification, and choosing suitable measures in accordance with different persons and seasonal conditions after more than ten years' clinical practice and researches. Radical operation as prior (as evil eliminating) and strengthening vital qi in perioerative period are best strategy for promoting rapid rehabilitation of early stage prostate cancer patients. Strengthening body resistance to eliminate evil was used in treating advanced prostate cancer patients. For example, a comprehensive treatment program for hormone-dependent patients was combined with endocrinotherapy and Chinese herbs for synergisic efficacy-enhancing actions. In this way, these patients' quality of life (QOL) were improved and time to castration resistant prostate cancer (CRPC) was delayed, even some patients were clinically cured. There are lack of effective medicines and methods for CRPC patients. Greatly tonifying original qi is mainly used for improving their clinical symptoms and prolonging survivals. Practice has proved staging based strategies and practice of IM has favorable advantages in treating prostate cancer, especially showing prospect in prolonging survival and postponing progression of advanced prostate cancer patients. Besides, it also could provide beneficial considerations and inspiration for combination of syndrome typing and disease identification.
Disease Progression
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Humans
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Male
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Medicine, Chinese Traditional
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Neoplasm Staging
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Prostatic Neoplasms, Castration-Resistant
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diagnosis
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Quality of Life
4.Mid-term follow-up results of laparoscopic radiofrequency ablation for renal cell carcinoma of T1aN0M0 stage.
Jian-nan SONG ; Xiao-zhi ZHAO ; Hui-bo LIAN ; Guang-xiang LIU ; Xiao-gong LI ; Gu-tian ZHANG ; Wei-dong GAN ; Hong-qian GUO
Chinese Journal of Surgery 2013;51(4):320-322
OBJECTIVETo determine the effect of laparoscopic radiofrequency ablation of T1aN0M0 renal cell carcinoma (RCC) with regular follow-up.
METHODSAll patients underwent surgery from March 2006 to March 2009. Eight cases were solitary kidney. Twenty-two cases of left RCC and 18 cases of right RCC were diagnozed by ultrasonography and CT scanning.All of the cases were T1aN0M0 stage. No metastasis was found by iconography test. By ultrasound positioning, laparoscopic radiofrequency were performed on the renal tumor. All patients were followed up with eGFR and enhanced-CT.
RESULTSAll patients underwent laparoscopic radiofrequency ablation surgery successfully. The mean operation time was (101 ± 19) minutes and the mean blood loss was (90 ± 14) ml (no blood transfusion pre- and post-operation). During postoperative follow-up, enhanced CT revealed complete ablation in 39 cases (the success rate was 97.5%), and 1 residue tumor was confirmed by enhanced CT 7 days post operation. This patient was under close surveillance because of solitary kidney. No progression of the residue tumor was found during the follow-up. One case of recurrence was confirmed by enhanced CT in 6 month after operation. The 3-year recurrence rate was 2.5%. No further intervation was performed on this patient and no change was found in the recurrence area during the follow-up. Both 3-year total survival rate and 3-year cancer specific survival rate were 100%. The mean eGFR was (72 ± 9) ml/(min·1.73 m(2)) in 3 years after surgery. There was no significant difference between pre-and post-operation (P > 0.05).
CONCLUSIONMid-term follow-up results show the effectiveness and safety of laparoscopic radiofrequency ablation in the treatment for T1aN0M0 RCC and have no negative influence on the renal function.
Carcinoma, Renal Cell ; mortality ; surgery ; Catheter Ablation ; methods ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; mortality ; surgery ; Laparoscopy ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; epidemiology ; Treatment Outcome
5.Effects of human alpha-mannosidase Man2c1 transgene on growth and metastasis of transplanted tumor in mice.
Dong-dong JIANG ; Yu-qin LIU ; Bei GU ; Zhi-guang XIANG ; Yun TIAN ; Yi-qun ZHOU ; Ji-yu JU ; Yin LIU ; Lian-feng ZHANG ; Li-ping ZHU
Acta Academiae Medicinae Sinicae 2007;29(4):528-532
OBJECTIVETo study the effect of human alpha-mannosidase Man2c1 transgene on tumor growth and metastasis in mice.
METHODSHepatoma cell H22 or squamous epithelial carcinoma cell S180 was subcutaneously inoculated into the right armpit of mice (wild type mice and 28#, 35#, and 54# transgenic mice). Tumor size was measured every week. Mice were sacrificed on day 9 or 10 and then the tumors were exercised and weighted. Tumors and lungs were fixed in formaldehyde and sectioned. The sections were stained with hematoxylin/eosin and examined under microscope. The red blood cells in spleen were destroyed by Tris-NH4Cl. Natural killer (NK) cell activity was detected with Yac-1 cell as target.
RESULTSH22 and S180 tumors grew faster in all the three transgenic mice (28#, 35#, and 54#) than in wild type mice. The average size and weight of tumors between the transgenic mice and wild type mice were significantly different (P<0.05). Most tumors in the transgenic mice invaded the surrounding tissues. In contrast, nearly all the tumors in wild type mice were capsulized. Three of 10 28# transgenic mice, 5 of 10 35# transgenic mice, 3 of 10 54# transgenic mice, and 1 of 10 wild type mice showed lung metastasis of H22 tumor. Two of 6 28# transgenic mice, 3 of 6 35# transgenic mice, 1 of 6 54# transgenic mice, and 0 of 6 wild type mice showed lung metastasis of S180 tumor. No difference of NK activity in spleen cells was observed between the transgenic mice and wild type mice.
CONCLUSIONShMan2c1 transgene promotes growth, invasion, and metastasis of transplanted H22 and S180 tumors in mice. hMan2cl transgene does not affect NK activity in splenocytes.
Animals ; Cell Line, Tumor ; Humans ; Killer Cells, Natural ; immunology ; Lung Neoplasms ; secondary ; Mannosidases ; genetics ; Mice ; Mice, Transgenic ; Neoplasm Invasiveness ; Neoplasm Transplantation ; Neoplasms, Experimental ; immunology ; metabolism ; pathology ; Spleen ; immunology ; Transgenes
6.Recipient dendritic cells modified by RNA interference targeting CD80 and CD86 elicit T cell hyporesponsiveness via enhanced T cell apoptosis.
Jun HONG ; Xiao-dong GU ; Jian-bin XIANG ; Zhe ZHANG ; Yi-wen ZANG ; Qun-hua ZHANG ; Shi-guang QIAN ; Zong-you CHEN
Chinese Medical Journal 2013;126(11):2139-2144
BACKGROUNDDespite extensive research, the mechanism of immature dendritic cells (DCs) induced immune hyporesponsiveness remains incompletely understood.
METHODSRecipient DCs from C3H mouse bone marrow cells were incubated with donor antigen from splenic lymphocytes of C57BL/6 mouse; these DCs were transfected with CD80/86 specific siRNA using lentiviral vectors. Flow cytometry was used to evaluate expression of CD80/86 on the antigen-pulsed recipient DCs. Immune regulatory activity was examined by mixed lymphocyte reaction, in which irradiated DCs were cultured with C3H spleen T cells. After the reaction, interleukin (IL)-2, IL-4, IL-10, and interferon (INF)-γ levels of mixed lymphocyte reaction culture supernatant were measured by enzyme-linked immunosorbent assay. The apoptotic T lymphocytes were identified by Annexin V and CD3 staining.
RESULTSThere was a significant inhibition of CD80/86 expression in DCs transfected with CD80/86 lentiviral vectors compared with the control groups (P < 0.05), indicating the specificity of RNA interference. Enzyme-linked immunosorbent assay results showed a significant reduction of INF-γ, IL-2 and IL-10 in the CD80/86 lentivirus transfected group compared to the control groups (P < 0.05). There was no significant difference in IL-4 levels between the groups (P > 0.05). We also showed that CD80/86 low DCs loaded with alloantigen (1) stimulated low T cell proliferative responses via the indirect recognition pathway and (2) enhanced apoptotic activity (P < 0.05) in co-cultured T cells.
CONCLUSIONSLentiviral vector transfection can effectively and specifically knock down target genes in DCs. The CD80/86 low DCs may show tolerogenic activity via induction of T-cell apoptosis, thereby modulating the activity of recipient-derived DCs. The use of this approach may potentially be clinically applicable.
Animals ; Apoptosis ; B7-1 Antigen ; genetics ; physiology ; B7-2 Antigen ; genetics ; physiology ; Dendritic Cells ; immunology ; Lentivirus ; genetics ; Lymphocyte Activation ; Mice ; Mice, Inbred C3H ; Mice, Inbred C57BL ; RNA Interference ; T-Lymphocytes ; cytology ; immunology
7.Bio-effects of water soluble taurine multi-wall carbon nanotubes on lungs of mice.
Xiang WANG ; Xiao-yong DENG ; Hai-fang WANG ; Yuan-fang LIU ; Tian-cheng WANG ; Yi-qun GU ; Guang JIA
Chinese Journal of Preventive Medicine 2007;41(2):85-90
OBJECTIVETo track the translocation of water soluble taurine multi-wall carbon nanotubes (14C-tau-MWCNTs) in lungs of the Kunming mice and evaluate the acute lung toxicity of intratracheally instilled tau-MWCNTs in Kunming mice.
METHODSHealthy adult Kunming mice were randomly grouped by their body weight (5 mice in each group). The lungs of mice were intratracheally instilled with 0.125, 0.25, 0.5 and 1 mg/kg of water soluble tau-MWCNTs and phosphate-buffered saline (PBS) as negative control. After exposure of 1, 7, 14 and 28 days, the blood and lung tissue were collected. Blood were assessed by using biochemical biomarkers of alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and angiotensin converting enzyme (ACE). Lung tissues were assessed by histopathology. The intratracheal instillation of 14C-tau-MWCNTs was conducted in the same way, after 1, 3, 7, 14, 21, 28 days, 14C-activity of the samples was counted in several organs, tissues, blood and feces etc.
RESULTS14C-activities were detected only in lungs, and with the exposure time proceeding the radioactivity descending from (80 +/- 7.7)% of the 1st day to (22 +/- 6.9)% of the 28th day. Activity of all groups of ALP and LDH went to the highest level on the 7th day postexposure, and back to the control level on the 28th day post-exposure, but LDH of 1 mg/kg group[(14.18 +/- 1.70) micromol x s(-1) x L(-1)] was still higher than that of control [(10.95 +/- 3.51) micromol x s(-1) x L(-1)] after 28 days' exposure. There was no significant changes observed in the activity of ACE. Histopathology found that lungs of all groups presented significant increase in pulmonary inflammation, lung cell proliferation. Many tau-MWCNTs were clearly found in some alveolar macrophages and bronchial epithelial cells.
CONCLUSIONIntratracheal instillation of water soluble tau-MWCNTs could induce slight bio-effects on lungs of Kunming mice.
Animals ; Instillation, Drug ; Lung ; drug effects ; Male ; Mice ; Mice, Inbred Strains ; Nanotubes, Carbon ; Taurine ; administration & dosage ; pharmacokinetics ; pharmacology ; Trachea
8.Experimental study of differentiation of canine bone marrow mesenchymal stem cell into fibroblasts in vitro.
Xiang-yang WEI ; Wei-yong LIU ; Guo-cheng SUN ; Hui OUYANG ; Chun-hu GU ; Xing-guang LIU
Chinese Journal of Surgery 2005;43(18):1198-1201
OBJECTIVETo explore the way of stably inducing canine bone marrow mesenchymal stem cells (BMSCs) to differentiate into fibroblasts and myofibroblasts in vitro, and provide seed cells for fabricating tissue engineering heart valves (TEHV).
METHODSAdult canine BMSCs were separated by a gradient centrifugation on Percoll (density 1.073 g/ml), then the cells were incubated in low-glucose Dulbecco Eagle's minimum essential medium (LG-DMEM) with 10% bovine calf serum. Cell phenotype were identified by immunohistochemistry staining. The second and third generation of BMSCs were committedly induced by conditioning culture medium, which were detected by immunohistochemistry staining. The induced-BMSCs were freezed, preserved and resuscitated after 7 d to observe the cell growth, proliferation and function.
RESULTSBMSCs deriving from the bone marrow mononuclear cells separated by a Percoll gradient were positive expression of alpha-smooth muscle antibody, vimentin and negative expression of CD34, laminin. About (50 +/- 3)% induced-BMSCs were positive expression of laminin. Approximately (85 +/- 3)% freezed induced-BMSCs could be resuscitated. And the growth, proliferation and function were well.
CONCLUSIONBMSCs could be committedly induced to differentiate into fibroblasts and myofibroblasts in vitro. It is suitable to be the seed cells.
Animals ; Cell Culture Techniques ; methods ; Cell Differentiation ; Dogs ; Fibroblasts ; cytology ; Mesenchymal Stromal Cells ; cytology ; Monocytes ; cytology ; Myoblasts ; cytology
9.Establishment and Analysis for Differential Gene Expression Profile of Left Atrium in Permanent Atrial Fibrillation Patients
Jie GAO ; Jian ZHOU ; xiong Pi SU ; Yan LIU ; Song GU ; tao Xi ZHANG ; guang Xiang AN
Chinese Circulation Journal 2017;32(11):1085-1090
Objective: To explore the relevant gene, signaling pathway for permanent atrial fibrillation (pAF) occurrence in order to provide the molecular basis of the pathogenesis of pAF. Methods: Our research included in 2 groups: pAF group, n=7 patients and Control group, n=4 healthy subjects with sinus rhythm. Agilent 4x44K microarray was used to analyze the mRNA in left atrium for differential gene expression profile. Based on Gene Ontology, KEGG and Biocarta databases, differentially expressed genes were studied for their relevant function and signaling pathway. Furthermore, the genes with significant differences were verified by quantitative real time PCR (qRT-PCR) in pathological specimen from 5 pAF patients and 5 normal heart donors. Results: The expression profile identified 987 abnormally expressed genes, 567 of them were down-regulated and 420 were up-regulated. 9 genes with significant differences were verified by qRT-PCR in pathological specimen and the changes were similar to microarray; those genes were closely related to pAF by involving left atrium fibrosis, electrical remodeling, inflammation, cellular stress response, metabolism and transcription regulation. GO and Pathway analysis indicated that down-regulated genes were mainly involved in metabolic processes; up-regulated genes had the effects on cellular stress response, immune response and platelet activation. Conclusion: Microarray technology identified some important genes related to pAF occurrence; such genes involved in left atrial structural and functional remodeling via affecting cellular metabolism, inflammation, immune response and thrombogenesis in relevant patients.
10.Effects of delayed opening of infarct-related artery on late left ventricular remodeling in patients with acute anterior myocardial infarction.
Li-kun MA ; Hua YU ; Xiang-yang HUANG ; Jun ZHU ; Ke-fu FENG ; Shi-guang LI ; Xiao-hong ZHANG ; Zheng-bin SHAO ; Xiao-mei DING ; Ji YAN ; Tong-yuan GU
Chinese Journal of Cardiology 2005;33(4):328-331
OBJECTIVETo assess the effect of delayed opening of the infarct-related artery (IRA) by percutaneous coronary intervention (PCI) on the late left ventricular remodeling after acute anterior myocardial infarction (AAMI).
METHODSSixty four patients with initial Q-wave AAMI and with the total occluded IRA conformed by angiogram at 9.1 +/- 2.3 (2 - 14) days after the onset were divided into successful PCI group and control group (not receiving PCI or the IRA not re-opened). Two-D echocardiogram was performed at acute phase (about 3 weeks), 2 and 6 months after onset of AAMI respectively to detect the left ventricular function and left ventricular wall motion abnormality (VWMA). The total congestive heart failure events were recorded during 6 months follow-up.
RESULTSVWMA scores, left ventricular ejection fraction (LVEF), left ventricular end-diastolic and end-systolic volume indexes (LVEDVI and LVESVI) were similar in 2 groups at acute phase and 2 months after the onset of AAMI. There were no differences between the parameters above at acute phase and 2 months in each group too. VWMA scores and LVEF did not changed significantly at 6 months in each group compared with those at acute phase and 2 months (P > 0.05). But LVEDVI and LVESVI were significantly smaller in the successful PCI group than those in the control group (P < 0.01, P < 0.05). The rate of congestive heart failure events was 19% in control group and 2.0% in successful PCI group (P > 0.05) respectively.
CONCLUSIONSDelayed opening of IRA in AAMI could prevent the late phase but not the early phase of left ventricular remodeling after AMI.
Aged ; Aged, 80 and over ; Angioplasty, Balloon, Coronary ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; pathology ; physiopathology ; therapy ; Myocardial Reperfusion ; Ventricular Remodeling