Cardiomyopathies ; complications ; Diverticulum ; complications ; Hematoma ; complications ; Humans ; Male ; Middle Aged

OBJECTIVETo identify the electrophysiological properties of long-QT syndrome (LQTS) associated missense mutations in the outer mouth of the HERG potassium channel in vitro.

METHODSMutations V630A and N633S were constructed by Megaprimer PCR method and cRNA were produced by T7 RNA polymerase. The electrophysiological properties of the mutation were investigated in the Xenopus oocyte heterologous expression system.

RESULTSCoexpression of mutant and wild-type HERG subunits caused a dominant-negative effect, and the currents were significantly decreased. Compared with wild-type HERG channels, V630A and N633S mutations were related to decreased time constants for inactivation for V630A/WT and N633S/WT at all potentials, reduced slope conductance and the voltage dependence of steady-state inactivation was shifted to negative potentials for V630A/WT and N633S/WT.

CONCLUSIONPresent study shows that LQTS associated missense mutations located in the outer mouth of HERG cause a dominant-negative effect and alterations in steady-state voltage dependence of channel gating of heteromultimeric channels suggesting a reduction in expressional current might be one of the pathophysiologic mechanisms of LQTS.

Animals ; DNA Mutational Analysis ; ERG1 Potassium Channel ; Electrocardiography ; Ether-A-Go-Go Potassium Channels ; genetics ; Humans ; Long QT Syndrome ; genetics ; Mutation, Missense ; Oocytes ; Patch-Clamp Techniques ; RNA, Complementary ; Xenopus

OBJECTIVETo study the cytotoxic T lymphocyte (CTL) response induced by dendritic cells (DC) transduced with recombinant adenovirus vector bearing hepatitis B virus surface antigen (HBsAg) gene in hepatocellular carcinoma HepG2. 2. 15 cells in vitro.

METHODSFull length HBsAg cDNAs were subcloned into pIND vector, followed by being cloned into pShuttle vector. The HBsAg gene fragments resulted from the pShuttle-S digested with PI-Sce and I-Ceu were linked to the linear adeno-X virus DNA. After packaged with HEK293 cells, the adenovirus expression vector was obtained. Then the recombinant adenovirus expression plasmid AdVHBsAg was transfected into human monocyte-derived dendritic cells, to construct AdVHBsAg hepatocarcinoma tumor vaccine. The effectiveness of transfection was detected by Western blot. Surface molecules of AdVHBsAg-DC were detected by FACS. Autologous T cell proliferation stimulated by AdVHBsAg-DC was detected by 3H-TdR assay. Cytotoxic CTL activity induced by AdVHBsAg-DC in vitro was detected by LDH assay.

RESULTSHBsAg gene in the inserted DNA of AdVHBsAg was confirmed by PCR, and predictive fragments proved by restriction enzyme digestion analysis were exhibited. Cell pathological changes appear after 10 days HEK293 cells transfected AdVHBsAg. Western blot analysis showed that HBV surface antigen gene was expressed in transfected DC, indicating that the transfection was effective. AdVHBsAg-DC was able to upregulate CD1a, CD11c, CD80, CD86 and HLA-DR. Autologus T cell proliferation induced by AdVHBsAg-DCs was significantly higher than that in DC control group and LacZ-DC group (P < 0.05). AdVHBsAg-DC activated CTL presented the specific killer ability to the hepatocellular carcinoma cells expressing HBsAg.

CONCLUSIONDC transduced with recombinant adenovirus HBsAg can express HBV-related hepatocellular carcinoma antigen (HBsAg), and AdVHBsAg-DC can induce potent immune response against HBsAg-positive hepatocellular carcinoma cells in vitro.

Adenoviridae ; genetics ; Antigens, CD1 ; metabolism ; CD11c Antigen ; metabolism ; Cancer Vaccines ; immunology ; Carcinoma, Hepatocellular ; immunology ; pathology ; virology ; Cell Line, Tumor ; Cell Proliferation ; Cytotoxicity, Immunologic ; immunology ; Dendritic Cells ; cytology ; immunology ; metabolism ; Genetic Vectors ; Hepatitis B Surface Antigens ; genetics ; metabolism ; Humans ; Liver Neoplasms ; immunology ; pathology ; virology ; Plasmids ; Recombinant Proteins ; genetics ; metabolism ; T-Lymphocytes, Cytotoxic ; cytology ; immunology ; Transfection

OBJECTIVETo compare the safety and efficacy of myocardial contrast enhancement (MCE)-guided and angio-pressure (AP)-guided transcoronary ablation of septal hypertrophy (TASH) for patients with hypertrophic obstructive cardiomyopathy (HOCM).

METHODSTASH was performed under MCE-guide (n = 47, group I) or AP-guide (n = 25, group II) for drug-refractory patients with HOCM. Myocardial perfusion imaging (MPI) data as well as other clinical data were compared.

RESULTSTASH both under MCE-guide or AP-guide resulted in similar and significant reduction of left ventricular outflow tract gradient (PG) and associated with significant symptom improvement (all P < 0.001). Dosage of ethanol use, peak-level of CK-MB and ablated myocardial area and incidence of arrhythmia were also similar between the two groups.Similar left ventricular/atrial dimension changes post TASH were observed in the 2 groups during follow-up. However, the first selected septal vessels were changed under MCE in 6 patients.

CONCLUSIONSOur data demonstrated that the MCE-guided TASH was not superior to AP-guided TASH in safety and efficacy. However, MCE-guided TASH can avoid the misplace of ethanol to avoid innocent myocardial ablation.

Adult ; Cardiac Catheterization ; methods ; Cardiomyopathy, Hypertrophic ; diagnostic imaging ; therapy ; Catheter Ablation ; methods ; Female ; Humans ; Male ; Middle Aged ; Myocardial Perfusion Imaging ; Ultrasonography

Adolescent ; Adult ; Aged ; Cardiomyopathy, Hypertrophic ; surgery ; Catheter Ablation ; methods ; Child ; Follow-Up Studies ; Heart Septum ; surgery ; Humans ; Middle Aged

OBJECTIVETo observe serum troponin I (TNI) level in patients with hypertrophic cardiomyopathy (HCM).

METHODSix hundreds and twelve HCM patients were analyzed prospectively from January 1990 to November 2007.Ultracardiography were detected for all the patients. The diagnostic criteria of HCM is ventricular wall thickness more than 15 mm. Serum TNI level was measured in 116 patients with HCM. Clinical data including age, gender, history, main symptoms, NYHA grade, coronary angiograph, electrocardiogram and echocardiography were compared between patients with normal and increased TNI levels.

RESULTSIn 116 patients who detected TNI, 62 of them (53.4%) had a degree higher than normal. The median TNI value of all these patients is 0.07 ng/ml (0 - 4.38 ng/ml). Sixty-nine patients (59.5%) had undergone coronary angiography. Only 9 of them (13.0%) could be diagnosised as coronary heart disease. The TNI values of HCM patients with or without coronary heart disease were similar. The factors related to a higher TNI value included maximal depth of ventricule (P < 0.05), significant T inversion (P < 0.01) and chest pain (P < 0.05). Compared to all the 612 patients, the ones who detected serum TNI were likely to have chest pain (45.7% vs. 34.5%, P < 0.01) and significant T inversion (75.9% vs. 30.1%, P < 0.01).

CONCLUSIONIncreased serum TNI could be seen in half of HCM patients, especially in those patients with chest pain or significant T inversion. It is therefore important to different these patients from patients with acute coronary syndrome.

Adult ; Cardiomyopathy, Hypertrophic ; blood ; diagnosis ; Coronary Disease ; diagnosis ; Diagnosis, Differential ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Troponin I ; blood

Child ; Female ; Fibrosis ; Heart Ventricles ; Humans ; Hypereosinophilic Syndrome ; diagnostic imaging ; surgery ; Myocardium ; pathology ; Thrombosis ; surgery ; Ultrasonography

OBJECTIVETo study whether Ca(2+)-activated Cl(-) current (I(to2)) contributes to the functional remodeling of the failing heart.

METHODSThe cardiac myocytes were isolated enzymatically from rapidly pacing-induced failing canine hearts (HF) at room temperature. Patch-Clamp whole cell recording technique was employed to record the I(to2). The Cl(-) transport blocker 4, 4'-diisothiocyanostilbene-2, 2'-disulfonic acid (DIDS, 200 micromol) was used to isolated the I(to2). The relations of I(to2) to L-type Ca(2+) current (I(Ca-L)) and to the membrane voltage under the constant intracellular [Ca(2+)]i were evaluated in HF and the normal hearts.

RESULTSWe found that the current density of I(to2) was significantly decreased in HF cells compared with the controls. At membrane voltage of 20 mV, for example, the I(to2) density was (3.02 +/- 0.54) pA/pF in control cells (n = 7) vs. (1.31 +/- 0.25) pA/pF in HF (n = 8) cells, P < 0.05. While the averaged I(Ca-L) density did not show difference between two groups. The time constant of current decay of I(to2) was similar in both types of cells. However, in intracellular Ca(2+) clamped mode with 100 micromol [Ca(2+)]i, I(to2) density was increased significantly in HF cells at membrane voltage of +30 mV or higher.

CONCLUSIONSOur results suggest that the decrease of I(to2) density may contribute to the prolongation of the action potential in failing heart. I(to2) density abnormality may cause cardiac arrhythmia and a delayed after-depolarization. Impaired Ca(2+) handing in HF cells rather than reduced CLCA function itself may result in this abnormality.

Animals ; Calcium ; physiology ; Calcium Channels, L-Type ; physiology ; Chloride Channels ; physiology ; Dogs ; Heart Failure ; physiopathology ; Patch-Clamp Techniques ; Ventricular Remodeling ; physiology

OBJECTIVEIn this study we investigated the functional restoration of nonsense mutations in the SCN5A gene.

METHODSThe readthrough-enhancing reagents were introduced to HEK293 cells to suppress one nonsense mutation W822X in the SCN5A gene. Patch-clamp was used to record the whole-cell current and dynamics. Western blot and immunofluorescence staining were used to certify the expression and the location of the sodium channel.

RESULTSIn transfected HEK293 cells, the nonsense mutation in SCN5A inhibited the expression level of full-length protein, and the sodium currents from the mutant channels were less than 3% of the wild-type level. Readthrough enhancement by decreasing translation termination efficiency with a siRNA targeting eukaryotic release factor eRF3a (a GTPase that binds eRF1), the sodium current from the mutant cDNAs was restored to as much as 30% of the wild-type. After the treatment by the readthrough-enhancing reagents, the channels from cDNA carrying W822X remained the features of wild-type phenotype, and Western blot and immunochemical staining also showed the expression of full-length channel proteins.

CONCLUSIONReadthrough-enhancing reagents could effectively suppress nonsense mutations in SCN5A and partially restore the function of sodium channel and the expression of full-length channels.

Codon, Nonsense ; HEK293 Cells ; Humans ; NAV1.5 Voltage-Gated Sodium Channel ; Patch-Clamp Techniques ; Plasmids ; RNA, Small Interfering ; Sodium Channels ; genetics ; metabolism ; Transfection

BACKGROUNDAtrial fibrillation is a common arrhythmia with multi-factorial pathogenesis. Recently, a single nucleotide polymorphism (G/T) at position 1057 in the KCNE4 gene, resulting in a glutamic acid (Glu, E)/aspartic acid (Asp, D) substitution at position 145 of the KCNE4 peptide, was found in our laboratory to be associated with idiopathic atrial fibrillation (atrial fibrillation more frequent with KCNE4 145D). However, the functional effect of the KCNE4 145E/D polymorphism is still unknown.

METHODSWe constructed KCNE4 (145E/D) expression plasmids and transiently co-transfected them with the KCNQ1 gene into Chinese hamster ovary-K1 cells and performed whole-cell patch-clamping recording to identify the possible functional consequences of the single nucleotide polymorphism. Quantitative data were analyzed by Student;s t test. Probability values less than 0.05 were considered statistically significant.

RESULTSA slowly activating, non-inactivating voltage-dependent current ((24.0 +/- 2.9) pA/pF, at +60 mV)) could be recorded in the cells transfected with KCNQ1 alone. Co-expression of wild type KCNE4 inhibited the KCNQ1 current ((7.3 +/- 1.1) pA/pF)). By contrast, co-expression of KCNE4 (145D) augment the KCNQ1 current ((42.9 +/- 7) pA/pF)). The V(1/2) of activation for the KCNQ1/KCNE4 (145D) current was shifted significantly towards the depolarizing potential compared to that for the KCNQ1 current ((-2.3 +/- 0.2) mv vs (-13.0 +/- 1.5) mv, P < 0.01)) without changing the slope factorkappa. Furthermore, KCNE4 (145D) also affected the activation and deactivation kinetics of KCNQ1 channels.

CONCLUSIONWe provide experimental evidence that the KCNE4 (145E/D) polymorphism exerts the effect of "gain of function" on the KCNQ1 channel. It may underlie the genetic mechanism of atrial fibrillation. Further studies on the functional association between I(Ks) and KCNE4 (145D) polymorphism in cardiac myocytes are suggested.

Animals ; CHO Cells ; Cricetinae ; Cricetulus ; Humans ; KCNQ1 Potassium Channel ; physiology ; Polymorphism, Single Nucleotide ; Potassium Channels, Voltage-Gated ; analysis ; genetics ; physiology