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Yong-Jin Kim

Publications and source records attributed to Yong-Jin Kim.

At least 19 recordsLinked to original sources
PubMed2005

Association between plasma lipids, and apolipoproteins and coronary artery disease: a cross-sectional study in a low-risk Korean population.

BACKGROUND: Due to the lower level of the traditional lipid profiles in Koreans than in the series of patients from the western countries, the need to investigate other lipid parameters to help identify the individuals at high risk of CAD has been emphasized. AIM AND METHODS: To investigate whether apolipoprotein B (apo B), apolipoprotein A-I (apo A-I) and their ratio give additional information to the traditional lipid risk factors for discriminating the individuals at high-risk for coronary artery disease (CAD), 544 subjects, who met the lipid criteria of total cholesterol (TC) <230 mg/dl, low-density lipoprotein cholesterol (LDL-C) <120 mg/dl and high-density lipoprotein cholesterol (HDL-C) >40 mg/dl were recruited. Patients were considered to be CAD(+) if they had > or =50% stenosis in at least one coronary artery. RESULTS: In men, TC and apo B/apo A-I ratio were significantly different between groups with and without CAD after adjusting for age and diabetes (P = 0.037 and 0.035), and in women, triglyceride (TG), HDL-C and apo B/apo A-I ratio were significantly different after adjusting for age, diabetes and smoking status (P = 0.006, 0.007 and 0.030, respectively). In the lowest quartile of TC, TG and LDL-C, and the highest quartile of HDL-C, only apo B/apo A-I ratio was associated with CAD in both men and women. The only variable showing a significant difference between patients with and without CAD was apo B/apo A-I ratio. In models assessing whether apolipoproteins give additional information to traditional lipid risk factors, HDL-C, LDL-C, apo B/apo A-I ratio and in women but not in men, TG and apo B were all independent markers for the presence of CAD. Among the nontraditional lipid factors, only apo B/apo A-I ratio showed its additional value for identifying the presence of CAD. CONCLUSION: Apo B/apo A-I ratio is the only variable that differentiates the patients with CAD from those without and, furthermore, gives additional information to that supplied by traditional lipid risk factors in a low-risk Korean population.

Aged↗
PubMed2005

IFN-gamma/IRF-1-induced p27kip1 down-regulates telomerase activity and human telomerase reverse transcriptase expression in human cervical cancer.

Telomerase activation is regulated by the expression of human telomerase reverse transcriptase (hTERT) and is a key step in the development of human cancers. Interferon-gamma (IFN-gamma) signaling induces growth arrest in many tumors through multiple regulatory mechanisms. The p27 tumor suppressor protein inhibits the formation of tumors through the induction of cell cycle arrest and/or apoptosis. We demonstrate here that p27Kip1 inhibits hTERT mRNA expression and telomerase activity through post-transcriptional up-regulation by IFN-gamma/IRF-1 signaling. The ectopic expression of p27 suppressed hTERT expression and telomerase activity in human cervical cancer cell lines, HeLa and HT3. Furthermore, hTERT promoter activity of mouse embryonic fibroblasts (MEFs) deficient in p27 (p27-/- MEFs) was significantly higher than that of wild-type MEFs. Overexpression of p27 suppressed hTERT promoter activity and telomerase activity of p27-/- MEFs. In addition p27 down-regulated E7 protein expression and in transiently transfected HeLa cells, E7 increased hTERT promoter activity. In conclusion, we propose that inhibition of the hTERT expression and telomerase activity may be a novel tumor suppressor function of p27.

Cell Cycle Proteins↗
PubMed2005

Late occurrence of adenosine-sensitive focal junctional tachycardia in complex congenital heart disease.

BACKGROUND: Although supraventricular tachycardia in complex congenital heart disease (CHD) has been reported after surgical repair, its exact electrophysiologic identification has been limited to intraatrial reentrant tachycardia (IART). Moreover, junctional tachycardia (JT) has not previously been described as a cause of late postoperative arrhythmia. METHODS AND RESULTS: Since 1993, a total of 12 patients with congenital heart disease presented with paroxysmal focal JT. The patients with only typical immediate postoperative junctional ectopic tachycardia were excluded. Medical records, standard electrocardiography and Holter monitoring were reviewed. An intracardiac electrophysiologic (EP) study was performed in 11 patients. Ten patients were in post-Fontan status (5.7% of total Fontan survivors). Focal JT occurred more frequently in heterotaxy syndrome among the Fontan survivors (7/52 vs. 3/124; P < 0.05). The commonest anatomy of the atrioventricular (AV) junction was complete AV canal in 8 patients. EP characteristics of focal JT were as follows: (1) various tachycardia mechanisms were identified (increased automaticity or a triggered mechanism in 6/11, and focal reentry in 5/11, including one concealed nodofascicular pathway) (2) ventriculoatrial conduction during tachycardia was either dissociation (7/12) or variable (5/12) (3) All JTs were terminated by adenosine. Class III antiarrhythmic agent was effective in 5/6. His bundle ablation was performed in one Fontan patient, who already had pacemaker because of accompanying intractable IART and sinus node dysfunction. CONCLUSION: Focal JT may be a source of late term supraventricular tachycardia in patients with complex CHD. The tachycardia mechanism was either automatic/triggered or reentrant. In all patients, JT was effectively terminated by adenosine.

Adenosine↗
PubMed2005

Differences in the immediate effects of smoking on left ventricular diastolic function between healthy volunteers and patients with type 2 diabetes mellitus.

BACKGROUND: In contrast to in-depth studies on the chronic hazardous effects of smoking, the immediate effects of smoking on left ventricular function have not been evaluated in detail. OBJECTIVES: We aimed to assess the hypothesis that smoking a cigarette might have more deleterious immediate impacts on left ventricular function in patients with diabetes mellitus than in healthy volunteers. METHODS: In all, 20 patients with type 2 diabetes mellitus and 25 healthy volunteers were consecutively enrolled. Mitral inflow parameters (peak early and late diastolic velocities, and deceleration time of early diastolic mitral inflow) and mitral annulus velocity parameters (systolic, late, and early diastolic velocity [E']) were obtained together with heart rate and blood pressure before and 5, 15, 30, 45, 60, and 75 minutes after smoking a cigarette. RESULTS: Transient elevations in heart rate and blood pressure were observed after smoking in both groups. In terms of mitral inflow parameters, transient trends toward abnormal relaxation were noted in both groups. For mitral annulus velocity parameters, in contrast to a temporary decrease in E' in healthy volunteers, reduction in E' persisted throughout the study for patients with diabetes. No significant change in peak early diastolic velocity/E' ratio was observed in healthy volunteers; however, a significant increase in peak early diastolic velocity/E' ratio lasted throughout the study period for patients with diabetes. Systolic velocity had no significant change during the study in either group. CONCLUSIONS: Even one cigarette can induce more protracted and more severe left ventricular diastolic dysfunction in patients with type 2 diabetes mellitus than in healthy volunteers. Our results have clinically relevant implications in the current era of increasing recognition of the diabetes epidemic and of the associated cardiovascular risks.

Adult↗
PubMed2005

Utilizing a database to interpret leaching characteristics of lead from bottom ashes of municipal solid waste incinerators.

This study focuses on evaluation and quantification of factors affecting leachability of lead from bottom ashes of municipal solid waste incinerators (MSWI) by utilizing a database. The database, which was constructed with data collected from sources such as research papers, questionnaires and reports, consists of 1149 data sets on 508 MSWI plants. Factors chosen as affecting lead leachability included: pH in the leachate, loss on ignition of bottom ash, total content of lead, and content of main elements such as Fe, Mn, Si and Al. The lead leachability was reduced to a minimum at neutral pH, increased with increasing pH and, especially, showed an abrupt increase at pH levels above 12. The main factor controlling the pH of the leachate appeared to be leachable Ca(2+) originating from portlandite (Ca(OH)(2)). Leaching concentration increased with increasing total contents of lead, and the relationship between leaching of lead and loss on ignition showed no distinct tendencies. The lead leaching ratio increased with decreasing total contents of Si, Mn and Fe. It is evident, therefore, that these numerous factors determine the leachability of lead in a simultaneous and complex manner.

Air Pollutants↗
PubMed2005

Twin AV node and induced supraventricular tachycardia in Fontan palliation patients.

INTRODUCTION: The coexistence of two distinct atrioventricular (AV) nodes has been described in congenital heart disease requiring Fontan type palliation. The purpose of this study was to evaluate the occurrence of twin AV node according to anatomical subgroups, and to determine its relation to tachycardia. METHODS: From 2001 to 2003, we performed an electrophysiologic (EP) study upon 52 consecutive patients who had undergone cardiac catheterization after Fontan completion. Atrial pacing was performed at three or more different atrial sites. RESULTS: In 10/52 patients, two different QRS complexes were recorded at different pacing sites, suggesting twin AV node (9/20 in right isomerism, 1/8 discordance AV connections, 0/24 other complex anomalies). AV reciprocating tachycardia (AVRT), presumably involving two AV nodes and a connecting sling, was induced in 6 of 10 patients who had twin AV node (4/6 used posterior AV node as an antegrade limb, 2/6 used an anterior AV node as an antegrade limb). Heterotaxy syndrome (P < 0.001) and complete AV septal defect (P = 0.002) were found to be risk factors for twin AV node. Junctional tachycardia (JT; HR > 150/min) with either VA dissociation (7/9) or second degree VA block (2/9) were induced by pacing or isoproterenol infusion in 9/52 patients. CONCLUSION: JT induction was associated with a twin AV node (P = 0.04), or a history of early postoperative junctional ectopic tachycardia (P = 0.02). A complicated AV node conduction system such as twin AV node was frequent in heterotaxy syndrome. Both AVRT and JT with VA block may be important causes of tachyarrhythmia in this patient group.

Adolescent↗
PubMed2004

Effects of intracoronary infusion of peripheral blood stem-cells mobilised with granulocyte-colony stimulating factor on left ventricular systolic function and restenosis after coronary stenting in myocardial infarction: the MAGIC cell randomised clinical trial.

BACKGROUND: Bone-marrow stem-cell transplantation has been shown to improve cardiac function in patients with myocardial infarction. We examined the feasibility and efficacy of granulocyte-colony stimulating factor (G-CSF) therapy and subsequent intracoronary infusion of collected peripheral blood stem-cells (PBSCs) in such patients. METHODS: We prospectively randomised 27 patients with myocardial infarction who underwent coronary stenting for the culprit lesion of infarction into three groups; cell infusion (n=10), G-CSF alone (n=10), and control group (n=7). Changes in left ventricular systolic function and perfusion were assessed after 6 months. By December, 2003, seven patients from the cell infusion group, three from the G-CSF group, and one from the control group had been assessed. FINDINGS: G-CSF injection and intracoronary infusion of the mobilised PBSC did not aggravate inflammation and ischaemia during the periprocedural period. Exercise capacity (mean treadmill exercise time: 450 s [SD 178] at baseline vs 578 s [168] at 6 months' follow-up, p=0.004), myocardial perfusion (perfusion defect 11.6% [9.6] vs 5.3% [5.0], p=0.020) and systolic function (left ventricular ejection fraction 48.7% [8.3] vs 55.1% [7.4], p=0.005) improved significantly in patients who received cell infusion. However, we noted an unexpectedly high rate of in-stent restenosis at culprit lesion in patients who received G-CSF, and therefore we stopped enrollment. INTERPRETATION: G-CSF therapy with intracoronary infusion of PBSC showed improved cardiac function, and promoted angiogenesis in patients with myocardial infarction. However, aggravation of restenosis could be a serious problem. In future studies with G-CSF based stem-cell therapy, patients should be carefully monitored for unexpected effects.

Arteries↗
PubMed2004

Impact of left ventricular diastolic function on exercise capacity in patients with chronic mitral regurgitation: an exercise echocardiography study.

BACKGROUND: Mitral regurgitation (MR) is known as one of the most frequent causes of heart failure and sudden death. In spite of increasing prevalence of MR, there have been no available data on cardiac determinants of exercise capacity in patients with chronic MR. HYPOTHESIS: This study aimed to investigate cardiac determinants of exercise capacity in patients with chronic MR. METHODS: We consecutively enrolled 32 patients (11 men, mean age: 44 +/- 14 years) who had greater than moderate MR with normal left ventricular (LV) systolic function (LV ejection fraction >50%). Conventional echocardiographic indices and parameters measured by Doppler tissue imaging at septal side of mitral annulus were obtained before exercise. Mitral regurgitation fraction, forward stroke volume, pulmonary venous flow velocities, and systolic pulmonary artery pressure (sPAP) were also obtained with standard methods. RESULTS: Left ventricular ejection fraction was 61 +/- 6% and MR fraction was 48 +/- 13%. All patients finished a symptom-limited treadmill exercise test with a peak heart rate of >85% of predicted maximum heart rate. Mean exercise time was 9.95 +/- 2.17 min, corresponding to 11 +/- 2 metabolic equivalents. Among pre-exercise echocardiographic variables, only early diastolic mitral annulus velocity (E') and pulmonary venous reversal flow velocity (PVa) showed a significant correlation with exercise time (r = 0.44, p = 0.011, and r = -0.40, p = 0.040, respectively), which persisted after multivariate analysis (p = 0.011 and 0.038, respectively). Other parameters such as systolic mitral annulus velocity, resting and postexercise sPAP, forward stroke volume, LV size, LV ejection fraction, left atrial size, and regurgitant fraction showed no significant correlation. CONCLUSIONS: Left ventricular diastolic function is an important determinant of exercise capacity in patients with chronic MR. Both E' and PVa, accepted surrogate estimates for LV diastolic function, may be useful for identifying patients with chronic MR and with poor exercise capacity.

Adult↗
PubMed2004

Leaching of brominated flame retardants in leachate from landfills in Japan.

Leachate samples were taken from seven different landfills and concentrations of brominated flame retardants (BFRs), i.e. polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA), were quantified. Leaching characteristics of BFRs, especially factors affecting leachability, were clarified to obtain basic information regarding the release of BFRs into the environment. The results obtained for observed levels of the sum of PBDE-47, -99 and -100 were n.d.--4000 pg/l for the raw leachate and n.d. for the treated one, respectively, and those of TBBPA were n.d.--620,000 pg/l for the raw leachate and n.d.--11,000 pg/l for the treated one, respectively. Three sites that not only had crushed material from bulk wastes such as waste electric and electronic equipment, but also were under operation or within a year since closure, indicated a higher concentration of BFRs than the other sites. In particular extremely high concentration of PBDEs was observed at a site with a large amount of organics. Considering the leaching characteristics of BFRs, there exists the possibility that leachability of PBDEs is influenced by the presence of dissolved humic matter (DHM) in the leachate. The high removal efficiency for BFRs in the leachate treatment process was also confirmed.

Carbon Isotopes↗
PubMed2004

Unique features of early diastolic mitral annulus velocity in constrictive pericarditis.

BACKGROUND: In most primary myocardial diseases, early diastolic mitral annulus velocity (E') decreases with disease progression. To our knowledge, constrictive pericarditis (CP) is the only condition without this phenomenon. OBJECTIVE: This study was performed to evaluate the diagnostic and pathophysiologic role of mitral annulus velocity in patients with CP. METHODS: In all, 17 patients with CP (9 men; mean age 46.5 +/- 14.3 years), 8 patients with cardiac tamponade (Tamp) (2 men; mean age 44.5 +/- 15.0 years), and age- and sex-matched control subjects for CP and Tamp were recruited for the study. Early mitral inflow velocity and E' were obtained while simultaneously recording respiration. In 8 patients with CP and in all patients with Tamp, these measurements were repeated after the relief of constrictive physiology or after pericardiocentesis. RESULTS: In patients with CP, E' was significantly higher than it was for control subjects (12.9 +/- 3.0 cm/s vs 9.8 +/- 2.4 cm/s, P <.01). An E' of 2 cm/s higher than the predicted normal E' could differentiate patients with CP from control subjects with a sensitivity of 76% and specificity of 82%. In 12 of 17 patients (71%), inspiratory E' was higher than expiratory E'-the opposite of mitral inflow variation. In 8 patients, E' decreased significantly after the relief of constrictive physiology (13.8 +/- 2.5 cm/s vs 9.3 +/- 3.1 cm/s, P <.05). In contrast, E' in the Tamp group was significantly lower than in the control group (6.8 +/- 1.6 cm/s vs 10.2 +/- 2.5 cm/s, P <.01), did not show significant respiratory variation, and increased significantly after pericardiocentesis (6.8 +/- 1.6 cm/s vs 9.5 +/- 3.0 cm/s, P <.05). CONCLUSION: E' is exaggerated in CP, which is helpful for diagnosis. The opposite phenomenon was noted in Tamp, a dissimilarity that might contribute to different hemodynamics.

Adult↗
PubMed2004

The pseudorestrictive pattern of transmitral Doppler flow pattern after conversion of atrial fibrillation to sinus rhythm: is atrial or ventricular dysfunction to blame?

Patients with paroxysmal atrial fibrillation (AF) who have recently converted from AF to sinus rhythm often exhibit a restrictive Doppler pattern in the transmitral flow (TMF) velocity. However, the mechanism of this phenomenon has not been well defined. We evaluated the temporal change of TMF pattern and hemodynamics after conversion of AF to in sinus rhythm in an animal model. Eight open-chest dogs underwent 3 hours of pacing-induced AF. TMF velocities and pressure data were acquired at baseline (sinus rhythm), immediately after conversion of AF, and every 10 minutes thereafter. Early diastolic TMF velocity was increased immediately after conversion and recovered to the baseline value in 20 minutes. Atrial systolic TMF velocity was reduced after AF and recovered to baseline value in 20 to 30 minutes. Early diastolic/atrial systolic TMF velocity was increased after conversion, and recovered to baseline value in 20 to 30 minutes. The mean left atrial (LA) pressure increased immediately, 10 and 20 minutes after the conversion of AF to sinus rhythm. The left ventricular end-diastolic pressure was increased and positive left ventricular dP/dt and tau were decreased immediately after AF, whereas they recovered within 10 minutes. In conclusion, a pseudorestrictive pattern of TMF after AF occurred as a result of transient LA mechanical functional impairment and increased LA pressure caused by LA stunning. Transient left ventricular diastolic dysfunction also effected the TMF velocity immediately after the conversion from AF to sinus rhythm, although it recovered faster than LA mechanical dysfunction.

Animals↗
PubMed2004

Transthoracic echocardiographic evaluation of coronary flow reserve in patients with hypertrophic cardiomyopathy.

Recently, it has become possible to measure coronary flow reserve (CFR) non-invasively with transthoracic echocardiography (TTE). Twenty-one hypertrophic cardiomyopathy (HCMP) patients with asymmetric septal hypertrophy who had either not started medication or had stopped medication for at least 24 h were enrolled, along with 29 normal subjects. Mean diastolic coronary flow velocity (CFmv) and time velocity integral of diastolic coronary flow velocity (CFtvi) were measured at the distal left anterior descending artery with a 7 MHz transducer at the baseline and after dipyridamole infusion at a dose of 0.56 mg/kg. CFR was defined as the ratio of CFmv after dipyridamole over CFmv before dipyridamole. The baseline values for CFmv and CFtvi were significantly higher (0.40+/-0.09 vs. 0.31+/-0.06 m/s, p<0.001, 0.25+/-0.07 vs. 0.16+/-0.04 m, p<0.001, respectively), while that for CFR was significantly lower (2.01+/-0.42 vs. 3.06+/-0.39 m/s, p<0.001) in the HCMP patients, compared to the normal subjects. In the HCMP patients, CFR showed a moderate negative correlation with both baseline CFmv (r=-0.522, p=0.015) and baseline CFtvi (r=-0.495, p=0.034). Treadmill test was performed in 14 patients with Bruce protocol. CFR, baseline CFmv and baseline CFtvi did not correlate with maximal exercise time. In seven patients, the CFR measured after verapamil treatment was not significantly different from that measured before treatment. In conclusion, in patients with HCMP, CFR is probably reduced due to the recruitment of vasodilatory capacity at the resting state and this reduction is not directly related to reduced exercise capacity. Also, CFR is not affected by treatment with calcium antagonist.

Adult↗
PubMed2004

Investigation on the humification of municipal solid waste incineration residue and its effect on the leaching behavior of dioxins.

In this study, we investigated the humification of municipal solid waste incineration residue through identification of extracted humic substances, and examined the leachability of dioxins by batch leaching test. The samples were incineration residues excavated from lysimeters 6-8 years after being filled. The results of investigation of humic substances showed that the top layers from the surface to a depth of 30-70 cm contained more humic substances than the other layers judging from the color of the samples and optical characteristics of the extracts. In particular, humification in the lysimeter filled with a small amount of compost had progressed through all the layers, not only the top one. The tests revealed that the leaching concentrations of dioxins increased with advanced humification and showed relatively good correlation to dissolved organic carbon (DOC) of leachate at each lysimeter. Humification advances from the surface first, and DOC generated from the humification may preferentially carry down the highly chlorinated dioxin compounds such as O8CDD as DOC-dioxin complexes. Comparing the content and leaching concentration according to depth, we observed not only a decrease in dioxin content but also an increase in leaching of the highly chlorinated dioxins at deeper layers in the lysimeters with the compost. This tendency seemed to result from biological activities.

Carbon↗
PubMed2004

Influence of coexisting surface-active agents on leachability of dioxins in raw and treated fly ash from an MSW incinerator.

The leaching behavior of dioxins from raw and treated fly ash (FA) under the coexistence of several types of surface-active agents (SAAs) was examined by batch leaching tests to obtain significant information not only for evaluating leachability of dioxins as hydrophobic organic pollutants (HOPs) under the severe environment in which SAAs coexist, but also for evaluating the reduction efficiency of dioxin-leachability from the treated FA. Enhancement of dioxin-leachability by sufficient addition of SAAs was observed in the leaching test, whereas addition of a smaller quantity depressed the leachability. The higher the degree of chlorination in PCDDs/PCDFs homologues, the more effectively the SAAs enhanced the leachability. Moreover, there was a large difference in the potential for leachability enhancement due to each surface activity, based on critical micelle concentration (CMC) of the SAAs although Aldrich humic acid enhanced the leachability at a much lower concentration than CMC. A comparison of the leachability in FA treated by several methods showed a difference in the reduction efficiency of leachability, depending on the adsorption of SAAs by each treated FA.

Carbon↗
PubMed2004

Association between cardiac valvular calcification and coronary artery disease in a low-risk population.

BACKGROUND: Mitral annulus calcification (MAC) or aortic valve sclerocalcification (AVSC) is common with aging and associated with coronary artery disease (CAD) in Caucasians. This study was performed to determine whether MAC or AVSC is also associated with, and has a power to predict, CAD in Koreans as in Caucasians. METHODS: Three hundred and eight patients with chest pain, who had undergone coronary angiography and transthoracic echocardiography, were enrolled (189 males; mean 60.5 +/- 9.8 years). RESULTS: The prevalence of MAC and AVSC was significantly more common in CAD (+) compared with CAD (-) group (83.9%:55.2%, 87.9%:57.5%, respectively, both p < 0.001). On multivariate analysis with MAC and AVSC along with conventional coronary risk factors (cRF), MAC, male gender, AVSC, and diabetes mellitus were significantly associated with CAD (p < 0.001, < 0.001, 0.010 and 0.014 respectively). Additionally, a positive linear relationship was found between the prevalence of both MAC and AVSC and the extent of CAD defined by the number of stenotic coronary arteries (both p < 0.001). Furthermore, the odds ratio for CAD in the group with both multiple valvular sclerocalcification (MVSC) and > or = 2 cRF was 12.3 compared to the < or = 1 cRF group without MVSC. CONCLUSIONS: MAC and AVSC were independently associated with CAD in a low-risk Korean population. Also, combination of MVSC with > or = 2 cRF increased the predictability of the presence of CAD. Therefore, the possibilities of CAD must be considered when MVSC is detected in transthoracic echocardiography in patients with > or = 2 cRF.

Aged↗
PubMed2003

Interferon regulatory factor-1 (IRF-1) is a mediator for interferon-gamma induced attenuation of telomerase activity and human telomerase reverse transcriptase (hTERT) expression.

Constitutive activation of the telomerase is a key step in the development of human cancers. Interferon-gamma (IFN-gamma) signaling induces growth arrest in many tumors through multiple regulatory mechanisms. In this study, we show that IFN-gamma signaling represses telomerase activity and human telomerase reverse transcriptase (hTERT) transcription, and suggest that this signaling is mediated by IRF-1. Ectopic expression of IRF-1 attenuated hTERT promoter activity. Murine embryonic fibroblasts (MEFs) genetically deficient in IRF-1 (IRF-1(-/-)) showed an elevated level (>15 times) of hTERT promoter activity as compared to the hTERT promoter activity of wild-type MEFs. The telomerase activity and hTERT expression in IRF-1(-/-) MEFs were downregulated by IRF-1 transfection. Interestingly, less extent of telomerase repression was observed in HPV E6 and E7 negative, p53 mutant HT-3 cells than in HPV 18 E6 and E7 positive HeLa cells (intact p53). These findings provide evidence that IRF-1 is a potential mediator of IFN-gamma-induced attenuation of telomerase activity and hTERT expression.

Animals↗