AIM : To construct and analyze eukaryotic expression plasmid inserted by Cx50 with V64G mutation through bioinformatics software.METHODS: The full coding domain sequence of Cx50 with V64G mutation was acquired from the blood of patients with cataract and was cloned into pcDNA3.1 /Amp (+).The constructed plasmid was identified with PCR , enzyme digestion and sequencing. The analysis of Cx50 with V64G mutation was performed with bioinformatics software.RESULTS : Cx50 with V64G mutation was successfully amplified and its eukaryotic expression plasmid was constructed. Valine-64 is well conserved in the first extracellular loop of connexin 50 in different species and also in different human α -type gap junctional proteins.CONCLUSION : The successive reconstruction and verification of eukaryotic expression plasmid containing Cx50 with V64G mutation established the foundation for further studying the mechanism of cataract.

Objective To observe field potentials (FPs) and activation sequence at Langendorff perfused guinea pigs heart,SD rat cardiac tissue strips perfnsed by Tyrede's solution and cultured ventricular cardiomyocytes of suckling mice by microehtrode arrays (MEA) technique.Method FPs and activation sequence were recorded from perfnsed heart,cardiac tissue strips (5 mm×5 mm) and cultured ventricular cardiomyocytes by MEA.Results (1) FPs could be recorded in hearts perfused for 30 to 90 min with a heart rate 90-120 beats/mitt FP durations of beth ventricular and atrial tissue were (210±78) ms and (164±58) ms,respectively and atrial ventricular conduction time wag (320±150) ms.(2) The excitability of Tyrode's solution perfused tissue strips wag risible for more than 2 h,and FP durations of ventricular and atrial tissue strips were (115.80 ±11.61) ms and (83.71 ±6.48) ms,respectively.(3)Spontaneous beating frequency (150±100) beats/rain and FPs could be readily recorded in cardiomyocytes cultured between 2 to 72 hours.Conclusion MEAs is a sensitive,low noise and stable technique for observing local tissue action potential and activation sequence of whole heart,cardiac tissue strips and cultured cardiomyoeytes.

OBJECTIVETo study the psychologic status and their influencing factors in congenital microtia patients and their families.

METHODSTotally one hundred and two congenital microtia patients (79 men, 23 women, mean age 13.62 +/- 7.2 years) were enrolled. The patients and their families answered the questionnaire written by ourselves to identify the psychosocial problems.

RESULTS(1) 23.5% patients were found to have severe psychosocial problems, such as lack of self-confidence, close and fear and so on. (2) With the growth of age, psychosocial problems of the patients were rated high (P < 0.05). (3) For patients who found their deformations early, psychosocial problems also were rated low. (4) For patients who found their deformations by themselves, psychosocial problems also were rated low. (5) The education and psychosocial impact for parents all affected patients deeply.

CONCLUSIONSTo prevent psychosocial problems, we should operate for patients as early as possible. And correct guidance is very important for youngsters.

Adolescent ; Adult ; Child ; Child, Preschool ; Congenital Abnormalities ; epidemiology ; psychology ; Ear ; abnormalities ; Family ; psychology ; Female ; Humans ; Inpatients ; statistics & numerical data ; Male ; Surveys and Questionnaires ; Young Adult

Objective The aVR lead four steps is a new algorithm for differential diagnosis of wide QRS complex tachycardia(WCT). The study explores the clinical value of this new algorithm on differential diagnosis of WCT. Methods Application of aVR lead four steps to analysis the electrocardiogram of patients with WCT proved by electrophysiological study. Every step's accuracy rate, sensitivity and specificity to differential diagnosis of ventricular tachycardia(VT)were calculated. The first step diagnosed VT according to presence of an initial R wave in the aVR lead. The second step diagnosed VT according to width of an initial r or q wave ＞40 ms in the aVR lead. The third step diagnosed VT according to notching on the initial downstroke of a predominantly negative QRS complex in the aVR lead. The fourth step diagnosised VT according to ventricular activation-velocity ratio(Vi/Vt)in the aVR lead, Vi/Vt ≤ 1 suggested VT. Results derived from aVR lead four steps algorithm were compared with results derived from Brugada and Vereckei four steps algorithm. Results A total of 113 patients with WCT were analyzed(31 supraventricular tachycardia, SVT and 82 ventricular tachycardia, VT). The accuracy rate of differential diagnosis VT is 91.2%, sensitivity is 90. 2% and specificity is 77.4%. The accuracy and sensitivity of the aVR lead four steps algorithm for differential diagnosis of WCT were superior to the Brugada Vereckei four steps algorithm (P ＜ 0. 05). The specificity of the Vereckei four steps algorithm was superior to aVR lead and Brugada four steps algorithm(P ＜0. 05),while the specificity of the aVR lead four steps algorithm was similar as Brugada four steps algorithm(P ＞ 0. 05). Conclusions The aVR lead four steps algorithm is associated with excellent accuracy rate, sensitivity for differential diagnosis of WCT. This algorithm is simple and could be easily learned and applied by physician.

Objective The study aimed to investigate the relationship between arrhythmia occurrence and nerve remodeling of thoracic spinalcord 1-5 nerves as well as myocardial electrophysiological remodeling in a metal stress rat model.Methods Thirty SD rats (weight 180-250 g)were randomly divided into control group (n = 10),stress group (n = 10) and fluoxetine group (n = 10,10 mg/kg i.p.for 3 weeks).Stress model (given by unpredicted chronic mild stress) was established according to Cronli's protocol.Following parameters were observed:( 1 ) ECG waveform change and arrhythmias ; (2)tissue field action potential duration (FAPD) of thoracic spinal cord 1 - 5 and cardiac tissue mapped by microelectrode arrays ( MEA ) technique; ( 3 ) myocardial growth-associated protein ( GAP-43 ),tyrosine hydroxylase (TH),choline acetyltransferase (CHAT) distribution observed by immunofluorescence and confocal laser scanning microscope (LSCM).ResultsThree weeks later:(1) The body weight,food intake,consumption of sugar water,the horizontal and vertical movement score,cleaning action of rats were significantly decreased,and fecal grains significantly increased,P-wave,P-R interval,QRS-wave and Q-T interval were significantly prolonged and heart rate was significantly reduced in stress group compared with control group ( all P ＜0.05).Incidence of ventricular premature beat was 80％ in stress group and 0％ in control group (P ＜ 0.05 ).The FA PD of thoracic spinal cord 1 -5 nerves [ ( 144.25 ± 12.63 )ms vs (79.56 ±8.01 )ms ] and of cardiac tissue [ LA ( 122.43 ± 19.34)ms vs (92.59 ± 7.61 )ms,RA ( 149.89 ± 14.68 )ms vs (105.18 ± 15.94) ms,LV(162.62 ± 7.04) ms vs (110.45 ±6.92) ms,RV (152.21 ± 30.49) ms vs ( 131.06 ± 12.04) ms ] were significantly prolonged,FAPD dispersion (FAPDd) significantly increased [ thoracic spinal cord 1 - 5 ( 13.3 ± 9.11 ) ms vs ( 9.36 ± 7.01 ) ms ] in stress group compared with the control group.Disarrangement of myocardial cells,proliferation of collagen fiber,infiltration of neutrophil and lymphocytes in the cardiac tissue were also observed and distribution of GAP-43,TH and CHAT was significantly increased in stress group.(2) All these changes could be partly reversed by the treatment with fluoxetine.Conclusion Metal stress induced cardiac autonomic nerve and myocardial electrophysiological remodeling and ventricular arrhythmia in rats which could be significantly attenuated by fluoxetine in this model.

Objective Therapy effects and cardiac electrical activity comparison of bone marrow stem cells (BMSCs) transplantation and sarcoplasmic reticulum Ca2+ -ATPase (SERCA2a) gene modified BMSCs transplantation after acute myocardial infarction ( AMI ) in rats.Methods Rats with AMI were divided into 4 groups ( n =30) randomly:normal group ( n =6 ),saline group ( control group,n =8 ),BMSCs transplantation group (BMSCs group,n=8) and SERCA2a gene modified BMSCs transplantation group ( BMSCs+rAd.SERCA2a group,n=8).After 14 days, cardiac function was evaluated by echocardiography and heart electrical activity was evaluated by electrocardiogram and microelectrode array (MEA) technology.Results ( 1 ) The transduction ratio of rAd.SERCA2a to BMSCs were 80％ to 90％.(2) Left ventricular ejection fraction on 14 days after therapy was significantly higher in BMSCs group and BMSCs + rAd.SERCA2a group than in control group ( all P＜0.05 ).(3) QT duration was significantly shorter[ (80.30±6.53 ) ms vs.( 105.31 ± 21.89) ms,P ＜ 0.05 ] and ventricular premature beats less frequent in BMSCs + rAd.SERCA2a group than in the control group.(4)MEA results suggested that isolated heart beat was significantly slowed down and frequent ventricular arrhythmias and atrioventricular block were recorded in control group.The maximum field potential and field potential duration on infarcted myocardium area in BMSCs group and BMSCs + rAd.SERCA2a group were significantly longer than those in control group [the maximum field potential:(0.51 ± 0.15),(0.55 ± 0.16),(0.23 ± 0.10) mV; field potential duration:(104.5±25.43),(107.67 ±24.01),(63.00 ±20.34) ms; all P ＜0.05].(5)The conduction time was the shortest and the cardiac electrical conduction consistency in myocardial infarction tissue was significantly improved in BMSCs + rAd.SERCA2a group.Conclusions BMSCs and SERCA2a gene modified BMSCs transplantation could significantly improve cardiac function and BNSCs +rAd.SERCA2a could also effectively improve electrical conduction of infarcted myocardium and attenuate the incidence of arrhythmia after myocardial infarction in rats.

Objective To investigate chwmc stress induced tissue action potential and pathological changes of thoracic spinal cord 1-5 nerves and heart in SD rats.Methods SD rats(weighing 180-250 g)were randomly divided into depressive group and control group(n=10 each).Depressive model (unpredicted chronic mild stress)waB established according to Gronli's protocol.The heart rhythm,tissue field action potential duration(FAPD)of thoracic spinal cord 1-5 nerves,atrium and veutricle were mapped by microclectrode arrays(MEA)technique.Hcart was sectioned and stained with Massion and HE for pathologicM analysis.Results After 3 weeks chronic stress,P wave[(35.09±7.92)ms vs.(25.43±3.38)ms,P＜0.05]and Q-T interval[(114.64±35.08)ms vs.(81.93±16.35)ms,P＜0.01]were significantly increased,FAPD of thoracic spinal cord 1-5 nerves and heart was significantly prolonged,atrial field action potential duration dispersion(FAPDd)was significantly increased,atrial premature beats(n=2)and ventricular premature beats(n=3)were also recorded in rats from depressive group.Moreover,increased collagen deposition was evidenced in Massion stained myocardium and increased inflammatory cell infiltration in the heart was found by both HE stain and electron microscope from depressive rats.Conclusion Chronic mild stress could activate sympathetic nerves system.promote inflammatory cell myocardial infiltration and myocardial fibrosis,induce arrhythmias by prolonging FAPD and increasing FADPd in thoracic spinal cord 1-5 nerves and/or heart tissue.

Objective To observe the maximal heart rate changes, atrioventricular (A-V) conduction block and atrial fibrillation (AF) inducibility in dogs with vagosympathetic trunk exposed to electromagnetic fields (EMFs). Methods The vagosympathetic trunk of adult dogs was separatedand exposed to EMFs 0.043 kHz(2.87 μG, n=5) and to EMFs 2 kHz(0.34 μG, n=6) for two to three hours. Simultaneously, the vagosympathetic trunk was stimulated with 20 Hz frequency and 1-8 V intensity for 0.1 ms. Heart rate, presence of A-V conduction block and AF inducibility were determined. Results After 5-minutes exposure to EMFs 0.043 kHz (2.87 μG), the maximal heart rate decreased 29%, the voltage applied to vagosympathetic trunk required to induce A-V conduction block decreased by 60% in experimental group versus 5% increase in control group. This effect lasted 2 to 3 hours.While vagosympathetic trunk exposure to EMFs 2 kHz (0.34 μG) was associated with significant increase in the incidence of atrial premature beats, atrial tachycardia and AF, these effects could be blocked by propranolol and atropine. Conclusions Our results showed that 0.043 kHz (2.87 μG) EMFs exposure might reduce while 2 kHz(0.34 μG) EMFs exposure might increase AF inducibility. Our study thus suggested autonomic nervous system of dogs could be affected by EMFs exposure and 0.043 kHz (2.87 μG) EMFs exposure might be a novel option for AF prevention.

BACKGROUNDArrhythmogenic right ventricular cardiomyopathy (ARVC) is one of the leading causes of sudden cardiac death. Recent studies have shown that ARVC, which is an inheritable genetic change, results from mutations in genes encoding desmosomal proteins. Plakophilin-2 is an important component of the desmosome. Because the full range of genetic variations related to ARVC is unknown and no related studies of the Chinese population have been reported, we aimed to investigate the genetic variation of plakophilin-2 in ARVC patients from the Southern Region of China.

METHODSGenomic DNA was isolated from peripheral blood samples of all 34 ARVC patients, who were screened through a clinical evaluation. They were used to detect variations in the sequences of the plakophilin-2 genes by polymerase chain reaction amplification in combination with direct sequencing.

RESULTSIn exon-1 of the plakophilin-2 gene, a deletion mutation (c.145_148 del GACA) was found in one family pedigree. The mutation was also found in exon-2, 4, and 11 of the plakophilin-2 gene. The QT interval dispersion of the ECG was considerably longer in the mutation group than in the non-mutation group of ARVC patients, and this result was statistically significant (P < 0.05).

CONCLUSIONWe discovered a plakophilin-2 mutation that prolongs the QT interval dispersion in the southern Chinese ARVC population.

Adult ; Arrhythmogenic Right Ventricular Dysplasia ; genetics ; Asian Continental Ancestry Group ; genetics ; Child ; China ; DNA Mutational Analysis ; Exons ; genetics ; Genetic Predisposition to Disease ; Humans ; Male ; Middle Aged ; Mutation ; Pedigree ; Plakophilins ; genetics

OBJECTIVETo investigate the ability of Porphyromonas gingivalis to invade human periodontal ligament cells (hPDLCs) and the effect of intracellular P. gingivalis on cell proliferation and osteogenic differentiation in vitro.

METHODSThe invasion ability of P. gingivalis in hPDLCs was tested using an antibiotic protection assay at the multiplicity of infection (MOI) of 10 and 100. The proliferation of the infected cells was detected using a CFDA-SE kit, and the cells were sorted by fluorescence-activated cell sorting (FACS) followed by alizarin red staining for detecting mineralization nodules deposition; real-time PCR was used to examine the expression of Runx2 mRNA in the cells.

RESULTSP. gingivalis actively invaded hPDLCs, and the internalized P. gingivalis was able to resist antibiotic treatment. The cells infected by P. gingivalis exhibited no significant suppression of cell proliferation, but showed significantly lowered capacity for osteogenic differentiation, down-regulated RUNX2 mRNA expression, and reduced mineral deposition.

CONCLUSIONIntracellular P. gingivalis does not significantly affect the proliferation of hPDLCs but inhibits osteogenic differentiation of the cells.

Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit ; metabolism ; Flow Cytometry ; Fluoresceins ; Humans ; Osteogenesis ; Periodontal Ligament ; cytology ; microbiology ; Porphyromonas gingivalis ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; Succinimides