Biomedical subjects

Jun Dong

Publications and source records attributed to Jun Dong.

At least 55 records · Page 3Linked to original sources

PubMed2004

Necessity for biatrial ablation to achieve bidirectional cavotricuspid isthmus conduction block in a patient following senning operation.

We report the case of a 28-year-old male patient with a 17-year history of recurrent symptomatic atrial tachyarrhythmia following Senning operation for transposition of the great arteries. Biatrial electroanatomic mapping and entrainment mapping revealed counterclockwise peri-tricuspid annulus reentry in which cavotricuspid isthmus tissue in both systemic and pulmonary venous atria was involved. Linear ablation of the cavotricuspid isthmus in the pulmonary venous atrium terminated the tachycardia but did not block the isthmus conduction, and the tachycardia was reinduced. Bidirectional isthmus conduction block could be achieved only after additional linear ablation targeting the cavotricuspid isthmus tissue in the systemic venous atrium. We conclude that biatrial ablation may be necessary in order to achieve bidirectional isthmus block and prevent tachycardia recurrence in some patients following Senning or Mustard operation.

Adult↗

PubMed2004

A long-term follow-up study of serum lipid levels and coronary heart disease in the elderly.

BACKGROUND: It is still controversial whether or not the correlation between lipid abnormality and coronary heart disease (CHD) becomes weaker in the elderly, and whether patients above 80 years old still benefit from lipid management for the secondary prevention of CHD. The purpose of this study is to assess the correlation between hyperlipidemia and the risk of CHD events in the elderly, and to determine if it is appropriate to use lipid-lowering drugs in those aged above 80, as prescribed by the recommended guidelines for lipid management. METHODS: One thousand two hundred and eleven retirees, mainly males (92%), aged 70 +/- 9 years, were enrolled in this study. Lifestyle habits and medical history were recorded via questionnaires. During the period 1986 - 2000, all subjects participated in an annual physical examination with a blood chemistry survey. The mean follow-up period was 11.2 years. Subjects with incidental illnesses, especially cardiovascular diseases, were diagnosed or treated promptly. Serum lipid parameters, including total cholesterol (TC), low and high-density lipoprotein cholesterol (LDL-C and HDL-C) and triglyceride (TG) levels were analyzed according to standardization of lipid and lipoprotein measurements. The association between lipid levels and the prevalence of acute myocardial infarction (AMI) or coronary death was analyzed statistically. RESULTS: Lipid abnormalities occurred in 2/3 of the 1211 subjects. The most common lipid disorder was high TC and high LDL-C, which was much more prevalent than high TG. Among the subjects, 51.6% had TC levels above 5.2 mmol/L. Mean TC and LDL-C reached peak levels in the 65 - 74 age group without significant decrease until ages over 90. The cumulative total number of deaths due to various causes was 397 in the 15-year follow-up period, with the mortality rate in the high lipid group slightly lower than that in the normal lipid group (30.6% vs 35.3%), although the difference was not significant (P = 0.1931). However, there were more cases of coronary death in the high lipid group than in the normal lipid group (7.9% vs 4.6%, P = 0.0045). When examining AMI survivors, more AMI cases were found in the high lipid group than in the low lipid group (20.9% vs 11.4%, P < 0.0001). The cumulative number of coronary deaths was 89 (with 88 cases above age 70), and the total number of CHD cases was 214 (17.7% of the whole group). Logistic regression analysis reveals that age, hypertension, LDL-C, and HDL-C are important risk factors for CHD. Lifestyle changes were common, but only 45% of the hyperlipidemic cases received drug treatment. Statins were commonly used only in recent years. CONCLUSION: The above results show that high TC and LDL-C levels are correlated with a high CHD risk even in people over 80. For elderly patients with clinical CHD and an aggregation of CHD risk factors, cholesterol-lowering therapy might be considered if the general health of the patient makes this permissible.

Aged↗

PubMed2004

Apparent protective effect of high density lipoprotein against coronary heart disease in the elderly.

BACKGROUND: This study was designed to evaluate the relationship between high-density lipoprotein cholesterol (HDL-C) level and acute myocardial infarction (AMI) and coronary heart disease (CHD) death and to explore the protective effect of HDL against CHD in the elderly Chinese. METHODS: Started from 1986, 1211 retirees (92% males) were enrolled consecutively and studied prospectively. The average starting age was 70 +/- 9 years, and that at the end of the study was 80 +/- 9 years. During the follow-up study, all the participants received yearly physical examination and blood chemistry survey from 1986 - 2000. The average duration of the follow up study was 11.2 years. The end point of this study was either attacks of AMI or death due to CHD and other causes. CHD risk factors were screened by logistic regression analysis. According to their HDL-C levels, cases were divided into low (< 1.03 mmol/L), medium (or normal, 1.03 - 1.56 mmol/L) and high (> 1.56 mmol/L) level groups, the differences in incidence of AMI and CHD death in each group were analyzed. RESULTS: The cumulative attacks of acute coronary syndrome (mostly AMI) were 214 cases, including 89 cases of coronary death and 308 death caused by other diseases during the follow up study. AMI occurrence and CHD death in normal HDL-C group were lower than those in the low HDL-C group by 40% and 53%; and those in the high HDL-C group were lower than in the normal group by 56% and 50%, respectively. Statistical analysis on normal lipid cases (411 cases, total cholesterol < 5.17 mmol/L, triglyceride < 1.69 mmol/L) revealed that the cases at low HDL-C level had similar rates of AMI events and CHD mortality as those of the entire group (including hyperlipidemia); however, AMI attacks and CHD deaths decreased significantly at the normal and high HDL-C levels. The results demonstrated that the protective effect of HDL against coronary artery disease is more prominent in people with low lipid level. CONCLUSION: Low HDL is an important independent risk factor for AMI attacks and CHD death in the elderly; high HDL has significant protective effect against coronary artery disease.

Aged↗

PubMed2004

[Prognostic analysis of lung function and chest X-ray changes of 258 patients with severe acute respiratory syndrome in rehabilitation after discharge].

OBJECTIVE: To analyze the clinical characteristics and prognostic changes of rehabilitating severe acute respiratory syndrome (SARS) patients through regular lung function tests and lung imaging studies after discharge and to retrospectively analyze the treatment data of these patients. METHODS: 258 discharged SARS patients received regular SARS-Co virus IgG test, lung function test and chest X-ray and/or high resolution computerized tomography (HRCT) examination at General Hospital of PLA two months after discharge, and the treatment data of these patients were retrospectively analyzed. RESULTS: 80.6% patients (208 of 258 patients) were positive for SARS-Co virus IgG. 21.3% patients (55 of 258 patients) showed lung diffusion abnormity (D(LCO) < 80%pred). Compared to 155 SARS-Co virus IgG positive patients without lung diffusion abnormity and 50 SARS-Co virus IgG negative patients, the 53 SARS-Co virus IgG positive patients with lung diffusion abnormity had longer fever course, higher dosages of glucocorticoid therapy, higher percentage of oxygen therapy and non-invasive ventilation. 51 of the 53 patients with lung diffusion abnormity received lung function test after one month, and the results of D(LCO) improved in 80.4% patients (41 of 51 patients). 40 of 51 patients with lung diffusion abnormity showed lung fibrosis, and the fibrosis decreased in 55% patients (22 of 40 patients) after one month. CONCLUSIONS: This finding suggests that lung fibrosis caused by SARS mostly occurs in severe patients, and it can resolve spontaneously. D(LCO) may be more sensitive than HRCT in evaluating the fibrotic changes.

Adolescent↗

PubMed2004

[Expressing of N gene encoding nucleocapsid protein of vesicular stomatitis virus and elementary application in ELISA].

The gene encoding the nucleocapsid (N) protein of vesicular stomatitis virus (VSV-NJ) was subcloned from pMD-VN5, and inserted into pBAD/Thio TOPO vector. The recombinant plasmid was identified by restriction analysis and PCR. It was sequenced to confirm the correct sequences and the correct junctional orientations of the inserted N gene. The results of SDS-PAGE and Western immunoblotting revealed that the N protein was expressed in Escherichia coli LGM194 in a high level and the recombinant fusion protein, which contained a N-terminal HP-Thioredoxin and a C-terminal polyhistidine tag. It had a molecular mass of approximately 63.5 kD and immunologically reactive activity. The recombinant protein was characterized and tested in an enzyme-linked immunosorbent assay (ELISA) format for potential application in the serodiagnosis of vesicular stomatitis using 186 serum samples from experimentally infected goats and guinea-pigs with VSV-NJ and VSV-IN, and from field origin and reference serum samples. The sensitivity and specificity of the ELISA were compared with those of the standard microtiter serum neutralization (MTSN) tests. The ELISA and MTSN test results were highly correlated for detection of VSV antibodies. The ELISA was as sensitive as the SN assay in detecting positive serum to VSV. The correlation between SN titers and ELISA titers was statistically significant. These data suggest that the recombinant fusion N protein of VSV could be used as a recombinant test antigen for the serodiagnosis of vesicular stomatitis. The ELISA based on the reconmbinant nucleocapsid protein may offer the best combination of rapidity, sensitivity, simplicity, economy, and laboratory biosafety of any of the methods yet developed for VSV serodiagnosis. This study lay on foundation for the development of the diagnosis methods in serology for VSV.

Amino Acid Sequence↗

PubMed2003

[Apparent protective effect of high density lipoprotein against coronary heart disease in the elderly].

OBJECTIVE: To evaluate the relationship between the level of high-density lipoprotein cholesterol (HDL-C) and acute myocardial infarction (AMI) events and coronary heart disease (CHD) death, and to explore the protective effect of high level HDL against CHD in the elderly Chinese. METHOD: A prospective study was done upon 1211 retired cadres, 92% of which were males, enrolled in succession since 1986, aged 70 +/- 9 on average when being enrolled and aged 80 +/- 9 on average by the end of the study. During a follow up study with an average duration of 11.2 years, till the year 2000 or a specific subject died of CHD or other disease, all the participants received yearly physical examination and blood chemistry survey. CHD risk factors were screened by logistic regression analysis. According to their HDL-C levels, the subjects were divided into 3 groups: low HDL-C (< 1.03 mmol/L), medium HDL-C (1.03 - 1.56 mmol/L), and high HDL-C (> 1.56 mmol/L) groups. The differences in AMI event and CHD death in each group were analyzed. RESULTS: 411 of the subjects were with normal blood lipid (normal blood lipid group, total cholesterol < 5.17 mmol/L, triglyceride < 1.69 mmol/L), 338 subjects were basically healthy (basically healthy group), and 214 subjects developed CHD during the follow-up (CHD group). 23.2% of the subjects could be included in the low HDL-C group, 68.7% in the medium HDL-C group, and 68.5% in the high HDL-C group. The low HDL-C rate was 16.9% in the basically healthy group and 35.0% in the CHD group (P = 0.000165). The high HDL-C rate was 12.4% in the basically healthy group and 3.3% in the CHD group (P = 0.000645). During the follow up study, 214 cumulative attacks of acute coronary syndrome (mostly AMI) were recorded with 89 deaths. 308 cases died of other diseases. The AMI event rate and CHD death rate in the normal HDL-C group were lower than those in the low HDL-C group by 40% and 53% respectively. The AMI event rate and CHD death rate in the high HDL-C group were lower than those in the normal HDL-C group by 56% and 50% respectively. In the normal lipid group, AMI event rate and CHD mortality in the individuals with low HDL-C level were lower than those in the individuals with medium HDL-C level by 79% and 77% respectively (both P < 0.0001). The number of individuals with high HDL-C level was low, however, no CHD death occurred among these subjects. CONCLUSION: Low HDL is an important independent risk factor of AMI attacks and CHD death in the elderly. High HDL protects effectively against coronary artery disease. High TC level weakens the protective effect of HDL-C.

Aged↗

PubMed2003

Nontransgenic hyperexpression of a complement regulator in donor kidney modulates transplant ischemia/reperfusion damage, acute rejection, and chronic nephropathy.

Complement activation during ischemia and reperfusion contributes to the development of tissue injury with severe negative impact on outcomes in transplantation. To counter the effect of complement, we present a strategy to deliver a novel complement regulator stabilized on cell surfaces within donor organs. The membrane-bound complement regulator is able to inhibit complement activation when the donor organ is revascularized and exposed to host-circulating complement. Application of this construct to donor kidneys protected transplanted tissues from ischemia/reperfusion injury and reduced the deposition of activated complement and histological signs of damage under conditions in which a nontargeted control construct was ineffective. Treatment of donor organs in this way improved graft performance in the short and long term. An analysis of the immune response in allograft recipients showed that reducing graft damage at the time of transplantation through complement regulation also modulated the alloresponse. Additionally, the results of perfusion studies with human kidneys demonstrated the feasibility of targeting endothelial and epithelial surfaces with this construct, to allow investigation in clinical transplantation.

Acute Disease↗

PubMed2003

Acute and long-term results of radiofrequency ablation of common atrial flutter and the influence of the right atrial isthmus ablation on the occurrence of atrial fibrillation.

AIMS: The purpose of this study was to evaluate the acute success rate and long-term efficacy of radiofrequency ablation of common type atrial flutter (AFL) by using a standardised anatomical approach in a large series of patients and to assess the influence of right atrial isthmus ablation on the occurrence of atrial fibrillation. There are no large scale prospective or retrospective multicentre studies for radiofrequency ablation of AFL. METHODS AND RESULTS: The study population consisted of 363 consecutive patients with AFL (mean age 58+/-16 years, 265 men) who underwent radiofrequency ablation at the inferior vena cava-tricuspid annulus (IVC-TA) isthmus using a standardised anatomic approach. Bidirectional isthmus block at the IVC-TA was achieved in 328 patients (90%). Following radiofrequency ablation, 343 patients (95%) were followed for a mean of 496+/-335 days. During the follow-up period, 310 patients (90%) remained free of AFL recurrences. Multivariate analysis identified five independent predictors of AFL recurrence: fluoroscopy time (p<0.001), atrial fibrillation after AFL ablation (p=0.01), lack of bidirectional block (p=0.02), reduced left ventricular function (p=0.035) and right atrial dimensions (p=0.046). Atrial fibrillation occurrence was significantly reduced after AFL ablation (112 in 343 patients, 33%) as compared to occurrence of atrial fibrillation before radiofrequency ablation (198 in 363 patients, 55%, p<0.001). CONCLUSIONS: The current anatomical ablation approach for AFL and criteria for evaluation of the IVC-TA isthmus block is associated with an acute success rate of 90% and a long-term recurrence rate of 10%. Radiofrequency ablation of common AFL results in a significant reduction in the occurrence of atrial fibrillation.

Acute Disease↗

PubMed2003

Delineation of intra-atrial reentrant tachycardia circuits after mustard operation for transposition of the great arteries using biatrial electroanatomic mapping and entrainment mapping.

INTRODUCTION: Intra-atrial reentrant tachycardia (IART) circuits after Mustard operation remain incompletely understood due to the complex atrial anatomy after extensive surgical procedures. The aim of this study was to delineate IART circuits and their relations to the individual anatomic boundaries in Mustard patients. METHODS AND RESULTS: Twelve patients (10 men and 2 women; age 29 +/- 4.6 years) with atrial tachyarrhythmias after Mustard operation were included in this study. During 14 IARTs and 2 focal atrial tachycardias, electroanatomic mapping and entrainment mapping were performed in both the systemic venous atrium and the pulmonary venous atrium. The latter was accessed via a retrograde transaortic approach. Thirteen IARTs used a single-loop reentrant circuit, and 1 IART used a dual-loop reentrant circuit. Ten (77%) of 13 single-loop reentrant circuits used the tricuspid annulus (TA) as their central barrier. The remaining 3 IARTs rotated around the inferior vena cava (IVC) (n = 2) or ostium of the right upper pulmonary vein (n = 1). In 6 (60%) of the 10 peritricuspid IARTs, both pulmonary venous atrium and systemic venous atrium components of the mid-portion of the TA-IVC isthmus were demonstrated to be part of the reentry. Overall, 12 (86%) of 14 IARTs in 10 patients were successfully ablated by bridging two barriers that constrained the reentrant circuit. Eight (80%) of 10 peritricuspid circuits were abolished by linear ablation connecting the TA to the IVC (n = 4), incisional scar (n = 2), patch (n = 1), and atriotomy (n = 1). CONCLUSIONS: In Mustard patients, the TA serves as the most frequent central barrier of IART. Biatrial electroanatomic mapping combined with entrainment mapping facilitates delineation of IART circuits in relation to their anatomic barriers and enables the design of individual ablation strategies to achieve high success.

Adult↗

PubMed2003

[Bioinformatic analysis of glioma development relative genes].

BACKGROUND & OBJECTIVE: Exploiting the transcriptional regulation mechanism by microarray and bioinformatics is an important method at genomic research field, and it is better than previous methods, by which we can easily analyze the gene expression regulative networks at genomic level. This study was designed to analyze the glioma gene expression profiles by clustering and bioinformatic retrieving to seek some tumor development relative genes that can be cloned for the purpose of function research in the future. METHODS: Firstly, we analyzed the glioma gene expression profiles of 16,363 genes by clustering, and chose 368 genes which expression differences were greater than 2 folds and the variances of 2 dots were smaller than 0.33. We selected 2 groups of genes that were expressed similarly. One group (11 cases) was upregulated with the glioma development and another (6 cases) was downregulated with the glioma development. Secondly, we determined the genomic information about those 17 genes and exploited their association with the development of gliomas. RESULTS: Two groups of genes were expressed similarly during the glioma development, one group was upregulated with the development of gliomas, and another was downregulated. Bioinformatic analysis showed that 3 of those genes (X55987, M85085, and AB011097) might be important tumor relative genes. CONCLUSION: By bioinformatics and microarray technologies, we found 3 genes, X55987(EDN, eosinophil-derived neurotoxin), AB011097 (ARTS-1, TNF receptor shedding regulator),and M85085(CStF, cleavage stimulation factor), which might be potential key tumor development relative genes that can be developed for therapy targets in the future.

Adult↗

PubMed2003

[Preliminary study on differentiation-inducing associated genes of human brain glioma cells in vitro].

BACKGROUND & OBJECTIVE: Glioma cells can be induced in vitro from low differentiation state to high differentiation state with differentiation-inducing agents, as our previous studies have showed. However, the relevant molecular mechanisms remained unclear. This paper was to establish differentiation-inducing gene expression pedigree of glioma cells and clone new relevant genes, for the purpose of offering genomic information on the molecular mechanisms of differentiation-inducing effects of tumor cells. METHODS: A low differentiated human brain glioma cell line (SHG-44-9) was treated with differentiation-inducing agents. The differentiation-inducing effects on glioma cells were determined using MTT assay, colony-forming efficiency in double-layer soft agar, cell morphological changes, flow cytometry, and fluoroimmunoassay of glial fibrillary acidic protein expression. Gene expression differences of tumor cells before and after inducing were assayed with cDNA microarray techniques. The relevant genes were cloned with differential display polymerase chain reaction (DD-PCR), and verified with Northern blot analysis, then the genomic information about these genes were analyzed with bioinformatics technologies. RESULTS: At dose of 1.75 mmol x L(-1), sodium butyrate caused a marked proliferation inhibitory effect on the SHG-44-9 cells, and drove them to a more mature phenotype. The expression of 98 genes changed obviously when were screened with gene chips immobilized with 18,000 human cDNAs, which were further proved by Northern blot analysis. Twelve differentiation-associated genes were cloned, including MIBP1 gene, which can regulate the c-myc gene expression and may be relevant with glioma cell differentiation. CONCLUSION: Ninety-eight genes associated with differentiation and 12 genes were cloned. These data may help to further study the molecular mechanisms of glioma cells differentiation, and to find new targets for gene therapy against glioma.

Base Sequence↗

PubMed2003

[Establishment of malignant progression associated gene expression profiles in human brain glioma].

OBJECTIVE: To establish malignant progression associated gene expression profiles in human brain glioma. METHODS: The primary (WHO grade II), recurrent (WHO grade III) and re-recurrent (WHO grade IV) glioma specimens were sequentially collected from one single patient. Gene expression of different tumor specimens and normal brain tissue of the same patient was compared by microarrary techniques. RESULTS: 197 differentially expressed genes with differential ratio > or = 3 were observed when compared with normal brain tissue. When the specimens (3 tumor, 1 normal brain) were paired with each other, 7 groups containing 489 genes (upregulated 193, downregulated 296) were observed. According to the descending frequency of the 109 genes with known function, they were the genes associated with development, metabolism, differentiation, signal transduction, DNA binding transcription, cellular receptor, immunity, ion-channel transportation, protein translation, cell backbone motion, stress, protooncogene and anti-oncogene and cell apoptosis, respectively. CONCLUSION: From the 197 differentially expressed genes found in one glioma patient experiencing tumor malignant progression, 17 genes screened out by bioinformatics assay, may offer valuable information on molecular mechanisms on genesis and malignant progression of glioma.

Brain Neoplasms↗

PubMed2003

[PRB technology in situ remediation of groundwater polluted by landfill leachate].

In this paper three reaction media zero valent iron (ZVI), a mixture of ZVI and activated carbon, a mixture of the ZVI and zeolites were used to design three kinds of permeable reactive barrier (PRB), viz. reactors A, B and C and to study the feasibility and the efficiency of the PRB technology in the remediation of leachate-polluted groundwater. The designs of the reactors took into account the relation of the permeability of the reactor with the permeability of the aquifer. The results indicated that the COD removal ratios of the reactor A, B and C were more than 80%, 90% and 70% respectively and the value of the BOD5/COD increased from 0.32 up to 0.781, 0.728, 0.716 respectively. Total nitrogen decreased from 50 mg/L to less than 10 mg/L and the removal ratio of the ammonium ranged from 78%-91%. Zeolites of the reactor C manifested effectiveness in the removal of heavy metals and hardness. The removal ratios of Mn ion, Zn ion and hardness were up to 90%, 80%, 81% respectively. These results indicate that PRB technology is an efficient method for the treatment of leachate-contaminated groundwater.

Bioreactors↗

PubMed2002

Early resolution of ST-segment elevation correlates with myocardial salvage assessed by Tc-99m sestamibi scintigraphy in patients with acute myocardial infarction after mechanical or thrombolytic reperfusion therapy.

BACKGROUND: Early resolution of ST-segment elevation is an indicator of final infarct size and clinical outcomes. Whether this correlation is an expression of initial infarct characteristics or degree of myocardial salvage achieved with reperfusion therapy is unclear. METHODS AND RESULTS: We prospectively included 243 patients with acute myocardial infarction (AMI) treated with either coronary stenting (122 patients) or thrombolysis (121 patients). Serial 12-lead electrocardiograms (ECG) were performed at baseline and 90 minutes after initiation of therapy. ST-segment resolution was defined as complete (> or =70%), partial (<70% to 30%), or no resolution (<30%). Paired technetium-99m sestamibi scintigraphic studies were performed to calculate the initial perfusion defect, final infarct size, and the proportion of initial defect salvaged with reperfusion (salvage index). ST-segment resolution correlated significantly with salvage index (P=0.008), final infarct size (P<0.001), and 6-month mortality (P=0.03). In the groups with complete, partial, and no resolution, salvage index was 0.54+/-0.32, 0.39+/-0.36, and 0.33+/-0.60; final infarct size was 12.5+/-12.0%, 20.0+/-13.9%, and 22.7+/-19.4% of the left ventricle; 6-month mortality was 2.4%, 6.2%, and 12.8%, respectively. After adjustment for baseline characteristics, ST-segment resolution was the second strongest predictor of salvage index (P=0.007) after the type of reperfusion, stenting, or thrombolysis (P=0.001); it was greater after stenting than after thrombolysis (P<0.001). CONCLUSION: Early resolution of ST-segment elevation in surface ECG correlates with myocardial salvage as assessed by scintigraphy in patients with AMI after reperfusion therapy. These data provide an explanation for the favorable prognostic value of the ST-segment resolution and support the use of this parameter to compare the efficacy of different reperfusion strategies.

Electrocardiography↗

PubMed2002

Radiofrequency ablation of cardiac arrhythmias using a three-dimensional real-time position management and mapping system.

A recently developed three-dimensional real-time position management system (RPM) uses an ultrasound ranging technique that enables multiple distance measurements between two reference catheters and a mapping catheter each equipped with ultrasound transducers. In addition to three-dimensional representation of the catheters and ablation sites it displays real-time movements of catheters (including the tip and shaft). A recently released version of the system enables additional geometry reconstruction of the heart chamber and activation mapping. This study included 21 patients (mean age 59 +/- 14.5 years) referred for radiofrequency catheter ablation of various arrhythmias. Geometry was reconstructed by tracing the endocardial contour of the respective heart chambers. Global and local color coded activation maps were constructed to confirm the nature of arrhythmia and to guide ablation. Spontaneous or induced arrhythmias were typical atrial flutter (n = 8), atypical atrial flutter (n = 3), atrioventricular nodal reentrant tachycardia (n = 3), atrial tachycardia (n = 2), atrial fibrillation (n = 2), ventricular tachycardia (n = 2), and Wolff-Parkinson-White syndrome (n = 1). Geometry reconstruction and mapping of arrhythmias were possible in 20 of 21 patients. RPM-guided radiofrequency ablation was successful in 19 (95%) of 20 patients. Due to difficulties in steering the RPM mapping/ablation catheter, in 6 (28%) successfully mapped patients, radiofrequency ablation was performed using another catheter. In one patient, the RPM-guided map was inconclusive and in another patient, ablation failed due to multiple reentrant circuits. No complications were observed. In conclusion, the new RPM system enables geometry reconstruction and three-dimensional positioning of the ablation catheters, reconstruction of the activation maps, marking of anatomic structures and reproducible tracking of multiple ablation sites. The system could be used to guide radiofrequency ablation of atrial and ventricular arrhythmias.

Arrhythmias, Cardiac↗

PubMed2002

Ectopic tachycardia originating from the superior vena cava.

We report a 65-year-old female patient with a 3-year history of symptomatic paroxysmal supraventricular tachycardia. Electroanatomic and basket catheter mapping revealed a focal tachycardia originating in the superior vena cava (SVC), 5 cm above the SVC-right atrium (SVC-RA) junction. An area of fractionated potentials and slow conduction was found on the anterior wall of the SVC. A line of conduction block extending downwardly and obliquely from the anteroseptal aspect to anterolateral aspect of the SVC forcing the impulse to enter the RA via the posterior aspect of SVC-RA junction was observed. Entrainment attempts from multiple sites within the SVC failed to demonstrate reentry as a mechanism of arrhythmia. The ablation approach consisted of isolation of the arrhythmogenic area from the rest of the SVC.

Aged↗

PubMed2002

[Experimental study of combination therapy against human glioma xenograft by differentiation-inducing agent and cytotoxic chemotherapeutic drug].

BACKGROUND & OBJECTIVE: Cytotoxic agent remains the main chemotherapeutic drug for glioma, although it has many limitations. It is not known whether differentiation-inducing agent can enhance antitumor efficiency of cytotoxic agent. This study was designed to investigate anti-tumor effects of differentiation-inducing agent in combination with cytotoxic chemotherapeutic drug against glioma. METHODS: Poorly-differentiated human brain glioma xenografted nude mice were treated with carmustine(1, 3-bis-(2-chloroethyl)-1-nitrosourea, BCNU) and sodium phenylbutyrate (SPB). The therapeutic effects were determined by measuring of tumor size, pathological changes, different phases of cell cycle of tumor cell proliferation, expression of differentiation antigen, and tumor cell apoptosis. RESULTS: The therapeutic effects of SPB plus BCNU group were much better than that of SPB or BCNU group alone, which were proved by lower growth rate of the tumor, cellularity decreasing, appearance of astroid-like polyglonal cells, G0/G1 ratio increasing, upregulation of GFAP expression. CONCLUSION: Combined application of SPB and BCNU can obviously inhibit proliferation of glioma, and promote differentiation of tumor cells.

Animals↗

PubMed1998

In situ hybridization assay of androgen receptor gene in hepatocarcinogenesis.

AIM:To determine the correlation between expression of androgen receptor (AR) gene and hepatocarcinogenesis.METHODS:Male SD rats were used as experimental animals and the animal model of experimental hepatocarcinoma was established by means of 3'-me-DAB administration. Androgen receptor mRNA was detected by a non-radioactive in situ hybridization assay in neoplastic and non-neoplastic liver tissues.RESULTS:The expression of androgen receptor mRNA was observed only in neoplastic cells and some atypical hyperplastic cells. In the liver tissue of control animal and the remaining normal liver cells adjacent to the carcinoma tissue, no positive signal was seen.CONCLUSION:Androgen has an important correlation with hepatocarcinogenesis and the expression of androgen receptor gene might be a mark event during hepatocarcinogenesis.

Journal Article↗