1.Gap junction remodeling and stem cell transplantation following acute myocardial infarction
Chinese Journal of Tissue Engineering Research 2007;0(19):-
Gap junctions(GJ) form the chemical signal channels between cardiocytes.The core proteins of these channels are the connexins(Cx).The quantity or distribution of Cx will lead to the remodeling of GJ, which contributed to arrhythmia and remodeling following the acute myocardial infarction.GJ remodeling is the key reason and pathological basis of arrhythmia following acute myocardial infarction.How to increase the number of myocardial cells and lighten or reverse the heart reconstitution have become a focal point.In the acute myocardial infarction cell transplantation treatment, stem cells are characterized by self-renewal and multi-directional differentiation have been paid great attention.This study summarized the basis and clinical research of GJ structure, function, distribution, remodeling and stem cell transplantation treatment following myocardial infarction.
2.Value of cranial MRI on diagnosing nonalcoholic Wernicke's encephalopathy
Chunjiu ZHONG ; Guoqiang FEI ; Lirong JIN
Journal of Clinical Neurology 1988;0(02):-
Objective To evaluate the value of cranial MRI on diagnosing nonalcoholic Wernickes encephalopathy (WE). Methods The clinical characters, cranial MRI features, and outcomes materials in six cases of nonalcoholic Wernickes encephalopathy were analyzed.Results Cranial MR and Flair imaging of the patients exhibited areas of increased T 2W and flair signals symmetrically surrounding the aqueduct and third ventricle and within the medial thalamus. One patient who became persistent vegetative state coexistenced increased T 2W and flair signal of the cortex. According to the follow-up results, the alterations of four patients in T 2W and Flair signals showed to resolve being consistent with the clinical recovery. One patient with persistent vegetative state had no change within two years of the follow-up.Conclusions Cranial MRI is of great value in diagnosing nonalcoholic Wernickes encephalopathy and reflects appropriately the pathological evolution of this disease.
3.Biological performance of Ni-Cr porcelain alloy
Qingyi SHEN ; Guoqiang LI ; Qun ZHONG
Chinese Journal of Tissue Engineering Research 2009;13(38):7555-7558
Biological performances of Ni-Cr porcelain alloy are highly correlated with released metallic ions. Released metal ions from Ni-Cr porcelain alloy, particularly Ni, Be can induce inflammation of the adjacent periodontal tissue and oral mucosa. In vitro evidence has indicated that the immune response can be altered by various metal ions. Allergic reactions due to metallic dental restorations have been documented. Ni has especially been identified as being highly allergenic. The cytotoxicity and corrosion level of Ni-Cr porcelain alloy is increased after recasting. The Ni-Cr porcelain alloy produced according to technology requirements has good biological safety. Ni-Cr porcelain alloy released a few of metal ions which might induce allergy and density of adjacent periodontal tissues, for the stimulation effect of these metal ions. There is no evidence to suggest that Ni-Cr porcelain alloy restorations has systemic toxicity or carcinogenic/genotoxic effect to human.
4.Experimental study of atherosclerosis ⅣChanges of aortic smooth cell proliferation, platelet free calcium and aggregation in atherosclerotic rabbits and the effects of 8501 on these changes.
Zhong WANG ; Yanhua HU ; Guoqiang ZHU
Chinese Pharmacological Bulletin 1986;0(05):-
Smooth muscle cell (SMC) proliferation, platelet free calcium level and aggregation of experimental atherosclerotic rabbits were investigated in this study. Aortic SMC ofhyperlipidemic rabbits in vitro showed higher growth activity than did normal rabbit SMC. And also hyperlipidemic serum stimulated SMC to proliferate at a significantly greater rate than control serum. Moreover, the level of platelet free calcium and the platelet aggregation was also higher in hyperlipidemic rabbits, indicating that activitated platelets possibly release more PDGF to act as a stimulator to SMC proliferation and calcium is an important factor to activate platelets. Furthermore, SMC from 8501-treated rabbits appeared lower proliferative rate than thecells from hyperlipidemic rabbits. And serum from those rabbits inhibited SMC proliferation compared with hyperlipidemic serum, the inhibitory effect was even stronger than that of normal serum. It may be relevant to the favorable effects of 8501 to TXA2/PGI2 balance.
5.Effect of Endothelin-1 on Atrial Fibrosis in Patients With Atrial Fibrillation
Yujie HONG ; Guoqiang ZHONG ; Zhiyuan JIANG ; Shu FANG ; Peizhen SUN
Chinese Circulation Journal 2016;31(2):146-150
Objective:To explore the effect of endothelin-1 on atrial ifbrosis in patients with atrial ifbrillation (AF).
Methods: A total of 72 patients with thoracotomy were studied, the patients were divided into 2 groups:AF group, n=39 and Sinus rhythm (SR) group, n=33. The mRNA and protein expressions of endothelin-1 (ET-1), platelet derived growth factor-B (PDGF-B) and collagen I (COL1) in right atrial appendage (RAA) tissue were measured by RT-PCR and Western blot analysis;meanwhile, the impact of ET-1 stimulation and non-selective ET-1 receptor antagonist (sulfafurazole SIZ) on PDGF-B mRNA and protein expressions in H9c2 cells were measured.
Results: ①The RAA tissue mRNA and protein expressions in AF group were higher than those in SR group, as for ET-1 (2.830 ± 2.276) vs (1.220 ± 0.887) and (0.835 ± 0.241) vs (0.286 ± 0.083), both P<0.01;for PDGF-B (2.568 ± 2.348) vs (1.567 ± 0.831) and (0.807±0.241) vs (0.381 ± 0.105), both P<0.05;for COL1α1 (3.376 ± 1.598) vs (1.629 ± 0.833) and (0.652 ± 0.210) vs (0.312 ± 0.12), both P<0.05.②The protein expressions of ET-1 and COL1 had positive correlation (r=0.580, P<0.01).③ET-1 promoted PDGF-B secretion in H9c2 cells in a concentration and time-dependent manner;SIZ could reduce such promotion.
Conclusion: ET-1 plays an important role in AF occurrence which might be related to PDGF-B regulation.
6.Effect of Tongxinluo capsule on the plasma C-reactive protein and endothelin-1 in acute coronary syndrome patients
Jiaqiang DENG ; Guoqiang ZHONG ; Jinru WEI ; Ruixing YIN ; Qi BI
Clinical Medicine of China 2008;24(6):538-539
Objective To study the effect of Tongxinluo on the plasma C-reactive protein(CRP)and endothelin-1(ET-1)in acute coronary syndrome(ACS) patients.Methods 100 patients with ACS were randomly divided into conventional therapy group and treatment group(conventional therapy+Tongxinluo gelatin capsule).The changes of CRP and ET-1 in the first day,7th and 14th day were observed.Results In the treatment group,CRP and ET-1 were significantly decreased in the 7th and 14th day(P<0.05,P<0.01),and there was significant decrease only in the 14th day(P<0.05)in the conventional therapy group.CRP and ET-1 levels in the treatment group were significantly different as compared with conventional thereapy group(P<0.01).Conclusion Tongxinluo capsule may protect blood vessel endothelium through inhibiting CRP and ET-1 to decrease the inflammatory response of endangium.
7.Effect of microRNA-101 on atrial fibrosis in human chronic atrial fibrillation
Zhiyuan JIANG ; Guoqiang ZHONG ; Fei XIAO ; Yan HE ; Yujie HONG
The Journal of Practical Medicine 2015;(6):890-893
Objective To investigate the effect of microRNA-101 (miRNA-101) on atrial fibrosis in human chronic atrial fibrillation (AF). Methods Right atrial appendages were obtained from 59 patients (30 with AF) undergoing cardiac surgery, including 47 patients with valve heart disease and 12 patients with congenital heart disease. The expression of miRNA-101 was determined by quantitative real-time PCR in the right atrial appendages of patients with and without AF. The cell-specific localization of miRNA-101 was detected by in situ hybridization assay. The mRNA and protein expression levels of transforming growth factor β typeⅠreceptor (TGFβRⅠ) and collagen type I (COL1) were determined by quantitative real-time PCR and Western-blot assay, respectively. Collagen in the right atrial appendages was observed by Masson staining assay. Results The expression of miRNA-101 was found to be significantly down-regulated in AF patients compared with patients with sinus rhythm (SR) (P < 0.05). The result of miRNA-ISH showed that miRNA-101, which was highly distributed within the connective tissues of heart, was down-regulated at about 24.9% in patients with AF compared with patients with SR. No significant differences at the mRNA expression level of TGFβRI was found between patients with AF and patients with SR (P > 0.05). But the protein expression of TGFβRI in patients with AF was significantly higher than that of patients with SR (P < 0.05). The mRNA and protein expressionsl of COL1 were significantly higher in patients with AF than thoset of patients with SR (P < 0.05). The collagen was significantly increased in patients with AF than that of patients with SR (P < 0.05). Conclusions Downregulation of miRNA-101 may contribute to atrial fibrosis in human atrial fibrillation by targeting TGFβRⅠ.
8.Relation between vagus nerves and remodeling of gap junction in superior vena cava myosleeve in dog with atrial fibrillation
Yun LING ; Guoqiang ZHONG ; Jinyi LI ; Yan HE ; Jingchang ZHANG ; Hongxing SONG ; Rixin XIONG
Basic & Clinical Medicine 2010;30(5):510-514
Objective To investigate the relationship between cardiac vagus nerves and changes of connexins(Cx)and intracellular gap junction(GJ)distribution pattern in superior vena cava(SVC)myosleeve in dog with atrial fibrillation(AF).Methods Twenty four hybrid dogs were divided into sham operation group(Sham group,n=8),SVC-AO fat pad removed group(RM group,n=8)and SVC-AO fat pad reserved group(RS group,n=8).In RM group and RS group,right atrial pacing was performed at a frequency of 500~650/min for 6 weeks to establish AF model.AF was induced by programmed stimulation or burst stimulation of atrial pacing.The expression and distribution of Cx40 and Cx43 in the SVC myosleeve tissue in three groups were analyzed by immunofluorescence staining.Transmission electron microscopy was used to observe the uhrastructural organization of gap junction(GJ).Results The rate of inducing sustained AF(> 15 min)in RS group was significantly higher than that in RM group (P < 0.01).The expression of Cx40 and Cx43 in the SVC myosleeve in sham group and RS group were significantly higher than that in RM group(P < 0.05).Furthermore,the expression of Cx40 and Cx43 in RS group were obviously higher than that in sham group(P <0.05).The ratio of end-to-end to side-to-side in RS group was lower than that in Sham group and RM group.Comparing with RM group,the channel of GJ became shorter and wider in RS group(P <0.05).Sarcomere was dissolved and mitochondrion showed vacuole degeneration in RS group.Conclusion The remodeling of Cx40 and Gx43 in SVC myosleeve tissue may be mediated by vagus nerves.It is conducive to the maintenance and stability of AF.However,this effect can be weakened by removing SVC-AO fat pad of canine.
9.Ischemic postconditioning attenuates myocardial cell injury by ischemia-reperfusion injury in rabbits
Yan HE ; Zhiyu ZENG ; Jinyi LI ; Guoqiang ZHONG ; Wei LI ; Weike LI ; Honghong KE
Basic & Clinical Medicine 2010;30(2):133-138
Objective To investigate the effects of ischemic postconditioning on apoptosis, structural and functional changes of mitochondria induced by myocardial isehemia/reperfusion (I/R) injury of rabbits and potential mechanism. Methods Eighty healthy rabbits were divided randomly into five groups: sham operation group ( Group Sham) , ischemic reperfusion group (Group IR) , ischemic preconditioning group (Group IP) , ischemic postconditioning group (Group PC) and 5-HD plus ischemic postconditioning group (Group PC +5-HD). All rabbits in the five groups were killed 4 h after reperfusion. The hearts were quickly collected for microscopy by TUNEL. We observed ultrastructural changes of myocardium under electron microscope and examined mitochondrial membrane potential and Ca~(2+) concentration, MDA content and SOD activity of myocardial mitochondria. Results Compared with group IR, the damage of mitoehondrial ultrastrueture was milder, the apoptosis rate decreased and Ca concentration and MDA content were much lower in group IP and group PC ( P < 0. 05 ). Mitochondrial membrane potential and SOD activity of myocardial mitochondria in group IP and group PC was significantly higher than that in group IR(P<0.05). The protective effect of PC against I/R injury was partially counteracted by 5-HD .Conclusion Ischemic posteonditioning can protect the heart from I/R injury, this is supported by improvement mitochondrial ultrastructure and by decreasing apoptosis, increasing mitochondrial membrane potential and SOD activity, alleviating Ca~(2+) overload and decreasing MDA content in myocardial mitochondria. The cardio protective effects may be explained by mitochondrial ATP sensitive potassium channel.
10.Transplantation of allogenic mesenchymal stem cells up-regulates connexin 43 expression in rats with myocardial infarction
Jinyi LI ; Guoqiang ZHONG ; Honghong KE ; Yan HE ; Lina WEN ; Zhuo WEI ; Yanmei ZHAO
Basic & Clinical Medicine 2010;30(4):337-342
Objective To investigate the alterations of connexin 43 (Cx43) expression and its distribution at different stages of myocardial infarction (MI) in rats after transplantation of allogenic mesenchymal stem cells (MSCs).Methods Wistar rats were ligated on the left anterior descending coronary artery to make MI models.They were injected with allogenic MSCs,which were induced by 5-aza and labelled by DAPI,during the second operation after 7 days of MI.In subgroups,MSCs were detected by fluorescence microscope.Cx43 expression and GJ distribu-tion were examined by immunohistochemistry after 4,8 or 12 weeks respectively.Results MSCs differentiated into cardiac muscle cell-like cells which were capable of pulsing spontaneously,expressing cTnT and forming myofilament in vitro.Transplanted MSCs can survive in MI host and upregulate Cx43 expression and normalize Cx43 distribution at ischemic zones after 4,8 and 12w.No change of Cx43 was seen at infarcted zones.Conclusion MSCs have the plasticity of differentiating into cardiac muscle cell-like cells which can continuously upregulate Cx43 expression and normalize Cx43 distribution at ischemic zones after 4,8 and 12w.