Post-dilatation improves stent apposition in patients with ST-segment elevation myocardial infarction receiving primary percutaneous intervention: A multicenter, randomized controlled trial using optical coherence tomography.

BACKGROUND: Stent failure is more likely in the lipid rich and thrombus laden culprit lesions underlying ST-segment elevation myocardial infarction (STEMI). This study assessed the effectiveness of post-dilatation in primary percutaneous coronary intervention (pPCI) for acute STEMI. METHODS: The multi-center POST-STEMI trial enrolled 41 consecutive STEMI patients with symptom onset <12 hours undergoing manual thrombus aspiration and Promus Element stent implantation. Patients were randomly assigned to control group (n=20) or post-dilatation group (n=21) in which a non-compliant balloon was inflated to >16 atm pressure. Strut apposition and coverage were evaluated by optical coherence tomography (OCT) after intracoronary verapamil administration via thrombus aspiration catheter, post pPCI and at 7-month follow-up. The primary endpoint was rate of incomplete strut apposition (ISA) at 7 months after pPCI. RESULTS: There were similar baseline characteristics except for stent length (21.9 [SD 6.5] mm vs. 26.0 [SD 5.8] mm, respectively, P=0.03). In post-dilatation vs. control group, ISA rate was lower (2.5% vs. 4.5%, P=0.04) immediately after pPCI without affecting final TIMI flow 3 rate (95.2% vs. 95.0%, P>0.05) or corrected TIMI frame counts (22.6±9.4 vs. 22.0±9.7, P>0.05); and at 7-month follow-up (0.7% vs. 1.8%, P<0.0001), the primary study endpoint, with similar strut coverage (98.5% vs. 98.4%, P=0.63) and 1-year rate of major adverse cardiovascular events (MACE). CONCLUSION: In STEMI patients, post-dilatation after stent implantation and thrombus aspiration improved strut apposition up to 7 months without affecting coronary blood flow or 1-year MACE rate. Larger and longer term studies are warranted to further assess safety (ClinicalTrials.gov identifier: NCT02121223).

A Risk Prediction Model for In-hospital Mortality in Patients with Suspected Myocarditis.

BACKGROUND: Myocarditis is an inflammatory disease of the myocardium that may lead to cardiac death in some patients. However, little is known about the predictors of in-hospital mortality in patients with suspected myocarditis. Thus, the aim of this study was to identify the independent risk factors for in-hospital mortality in patients with suspected myocarditis by establishing a risk prediction model. METHODS: A retrospective study was performed to analyze the clinical medical records of 403 consecutive patients with suspected myocarditis who were admitted to Ningbo First Hospital between January 2003 and December 2013. A total of 238 males (59%) and 165 females (41%) were enrolled in this study. We divided the above patients into two subgroups (survival and nonsurvival), according to their clinical in-hospital outcomes. To maximize the effectiveness of the prediction model, we first identified the potential risk factors for in-hospital mortality among patients with suspected myocarditis, based on data pertaining to previously established risk factors and basic patient characteristics. We subsequently established a regression model for predicting in-hospital mortality using univariate and multivariate logistic regression analyses. Finally, we identified the independent risk factors for in-hospital mortality using our risk prediction model. RESULTS: The following prediction model for in-hospital mortality in patients with suspected myocarditis, including creatinine clearance rate (Ccr), age, ventricular tachycardia (VT), New York Heart Association (NYHA) classification, gender and cardiac troponin T (cTnT), was established in the study: P = ea/(1 + ea) (where e is the exponential function, P is the probability of in-hospital death, and a = -7.34 + 2.99 × [Ccr <60 ml/min = 1, Ccr ≥60 ml/min = 0] + 2.01 × [age ≥50 years = 1, age <50 years = 0] + 1.93 × [VT = 1, no VT = 0] + 1.39 × [NYHA ≥3 = 1, NYHA <3 = 0] + 1.25 × [male = 1, female = 0] + 1.13 × [cTnT ≥50 µg/L = 1, cTnT <50 µg/L = 0]). The area under the receiver operating characteristic curve was 0.96 (standard error = 0.015, 95% confidence interval [CI]: 0.93-0.99). The model demonstrated that a Ccr <60 ml/min (odds ratio [OR] = 19.94, 95% CI: 5.66-70.26), an age ≥50 years (OR = 7.43, 95% CI: 2.18-25.34), VT (OR = 6.89, 95% CI: 1.86-25.44), a NYHA classification ≥3 (OR = 4.03, 95% CI: 1.13-14.32), male gender (OR = 3.48, 95% CI: 0.99-12.20), and a cTnT level ≥50 µg/L (OR = 3.10, 95% CI: 0.91-10.62) were the independent risk factors for in-hospital mortality. CONCLUSIONS: A Ccr <60 ml/min, an age ≥50 years, VT, an NYHA classification ≥3, male gender, and a cTnT level ≥50 µg/L were the independent risk factors resulting from the prediction model for in-hospital mortality in patients with suspected myocarditis. In addition, sufficient life support during the early stage of the disease might improve the prognoses of patients with suspected myocarditis with multiple risk factors for in-hospital mortality.

Imbalanced response of ATP-binding cassette transporter A1 and CD36 expression to increased oxidized low-density lipoprotein loading contributes to the development of THP-1 derived foam cells.

ATP-binding cassette transporter A1 (ABCA1) and CD36, type B scavenger receptor, function as the key mediators of macrophages cholesterol efflux and intake, respectively. However, their contribution to development of foam cells still remains uncertain. We here examined the effects of increased oxidized low-density lipoprotein (oxLDL) loading on the ABCA1 and CD36 expression, and lipid accumulation in THP-1 macrophages. The cultured THP-1 macrophages were treated with different copper-oxLDL concentrations. The intracellular lipid contents and cholesterol efflux were measured, and the ABCA1 and CD36 expression were assessed. We found that expression of ABCA1 and CD36 were coordinately induced upon low to moderate doses of oxLDL loading. However, higher doses of oxLDL stimulation resulted in the imbalanced expression of ABCA1 and CD36 proteins with more preferentially suppressed ABCA1 protein, attenuated cholesterol efflux and development of THP-1 derived foam cells. The PPAR-γ expression was remarkably induced, and PPAR-γ agonist, pioglitazone, significantly promoted the ABCA1 and CD36 expression. Additionally, ABCA1 and CD36 proteins were strong colocalized in THP-1 macrophages membrane. In conclusion, the more preferentially suppressed ABCA1 expression as compared with CD36 at higher doses of oxLDL stimulation may be the initiator for the formation of macrophage-derived foam cells.

[Evaluation of myocardial perfusion in patients with coronary slow flow by myocardial contrast echocardiography].

OBJECTIVE: To explore myocardial perfusion of patients with coronary slow flow (CSF) using myocardial contrast echocardiography. METHODS: Myocardial contrast echocardiography was performed in coronary artery angiography diagnosed CSF patients (n = 20) and control patients (n = 20). The images at baseline and after low dose dobutamine stress test were analyzed by automatic tracking software and the maximal amplitude score A, the mean ascending slope of the curve ß and the product of A×ß were measured. The reserve of A×ß was also calculated. Electrocardiogram at rest and at each stage of dobutamine stress test was obtained simultaneously. RESULTS: At baseline, the A [(6.85 ± 2.99) dB vs. (7.01 ± 3.49) dB], ß[(0.59 ± 0.33)/s vs. (0.61 ± 0.38)/s] and A×ß [(3.48 ± 1.46) dB/s vs. (3.31 ± 0.96) dB/s] values were similar between CSF group and control group (all P > 0.05). After dobutamine stress test, both ß and A×ß were significantly increased in two groups. The ß [(0.89 ± 0.42)/s vs. (1.31 ± 0.54)/s, P < 0.01] and A×ß [(5.82 ± 2.69) dB/s vs. (8.07 ± 2.76)dB/s, P < 0.05] in CSF group were significantly lower than in control group. Electrocardiogram of all the subjects was normal at rest, but the electrocardiogram positive rate was significantly higher in CSF group than in control group after dobutamine stress test (12% vs. 2%, 60% vs. 10%, P < 0.01). CONCLUSIONS: Dobutamine stress test could induce myocardial perfusion abnormalities in patients with coronary slow flow phenomenon.

[KCNQ1 mutation in patients with lone atrial fibrillation].

OBJECTIVE: Recent studies suggest that mutation of the slow delayed rectifier potassium channel [I(Ks)] contributes to familial atrial fibrillation (FAF). In the current study, we explored the potential association between KCNQ1 polymorphism with lone AF (LAF). METHODS: Clinical data and blood samples were collected from 95 Han Chinese patients with LAF and matched healthy controls. Variants of the KCNQ1 gene were identified using single-strand conformational polymorphism (SSCP) analysis. A case-control association study in KCNQ1 identified four known single-nucleotide polymorphisms (SNPs) during SSCP screening of the 95 LAF patients and 190 healthy controls. RESULTS: Three new variations were identified in KCNQ1 from 95 sporadic LAF including 1 in 5'UTR(c.-22T > C), 1 in exon9 synonymous mutation (c.1008C > T) and 1 in intron region (c.1590 + 31A > T). These variations were heterozygous and not presented in 190 healthy controls. Highly significant difference was detected between LAF group and control groups in rs760419 polymorphism. Logistic regression revealed that rs760419 was independent risk factor for LAF(OR = 2.056, P = 0.001). CONCLUSIONS: KCNQ1 mutation is associated with LAF and rs760419 polymorphism is a susceptible marker for LAF.

[Clinical application of VerifyNow-P2Y12 assay in evaluation of platelet inhibition efficacy of clopidogrel].

OBJECTIVE: To evaluate the platelet inhibition efficacy in patients under regular maintenance dose of clopidogrel by VerifyNow-P2Y12 assay and explore the clinical characteristics of clopidogrel non-responders and related predicting factors. METHODS: A total of 99 patients underwent percutaneous coronary intervention procedure and receiving clopidogrel in regular maintenance dose for at least 1 week were enrolled. Platelet reactivity, including baseline, P2Y12 reaction unit (PRU), and platelet inhibition rate were measured with VeifyNow-P2Y12 assay. The dosage of anti-platelet drugs, combination with any other drugs, clinical characters in baseline of all enrolled patients were analyzed. PRU ≤ 240 was used as cut-off to identify clopidogrel responder and clopidogrel non-responder. In the non-responder group, patients were further separated into 3 sub-groups (types) according to the baseline and platelet inhibition rate: type I with high baseline, high inhibition rate, representing false non-responder; type II with low inhibition rate, representing true non-responder and type III mixed type. RESULTS: In this study, 48 of 99 patients were found to be clopidogrel non-responder (48.5%). The ratio of type I, type II and type III in the non-responder group was 9.1% (n = 9), 27.3% (n = 27), and 12.1% (n = 12), respectively. Baseline platelet value in female patients was significantly higher than in males (P < 0.01), number of females with high PRU also is higher than males (P < 0.01), female gender was a predict factor for type I non-responder (OR = 6.5, 95%CI 2.295 - 18.407, P < 0.01). BMI > 24 kg/m(2) was a risk factor for clopidogrel non-responder (P < 0.05), and may be regarded as a predict factor for type II non-responder (OR = 3.207, 95%CI 1.375 - 7.485, P < 0.01). Age, hypertension, diabetics, smoking, hyperlipidemia, CRP and pantoprazole use do not show significant correlation with baseline and platelet inhibition rate. CONCLUSIONS: Clopidogrel responses could be reliably detected by VerifyNow-P2Y12 assay. Female gender and high body weight are independent risk factors for clopidogrel non-responses.

[Diagnostic value of 320-slice computed tomography coronary angiography to assess in-stent restenosis].

OBJECTIVE: To evaluate the diagnostic accuracy of 320-slice CT coronary angiography (CTA) in the evaluation of in-stent restenosis (ISR, ≥50% luminal narrowing) in comparison with quantitative coronary angiography (CAG). METHODS: A total of 69 patients with previous stent implantation who underwent both CTA and CAG were prospectively included. We assessed diagnostic valve for ISR with CTA in comparison with CAG. RESULTS: A total of 110 stents were implanted in these patients.CAG identified 14 ISR. CTA correctly identified 13 ISR and misdiagnosed 5 ISR in stents without ISR. Besides, 6 stents could not be evaluated by CTA due to unsatisfied image quality. Accordingly, sensitivity, specificity, positive and negative predictive value of CTA for diagnosing ISR were 93%, 89%, 54% and 99%, respectively. The image quality of CTA was significantly better in larger stents (percentages of good and moderate stent image of ≥3.0 mm and <3.0 mm: 56% vs. 27%, 25% vs. 49%) and which was linked with better diagnostic coincidence rate (95% vs. 78%) for larger stents. The image quality of CTA was significantly better in stents with thinner stent strut thickness (percentages of poor CTA stent image quality of stent strut thickness<140 µm and ≥140 µm: 12% vs. 45%, P<0.01) and which was associated with better diagnostic coincidence rate for stents with thinner stent strut thickness (94% vs. 76%, P<0.05). The image quality of CTA was also significantly better in single stent (percentages of poor CTA stent image quality of single stent vs. overlap and dedicated stent: 17% vs. 36%, P<0.05). However, heart rate (≥65 beats/min vs. <65 beats/min) during CTA acquisition was not associated with image quality and the diagnostic coincidence rate (all P>0.05). CONCLUSIONS: Our results indicate that 320-slice CTA allows accurate noninvasive assessment of significant in-stent restenosis in selected patients. Stents with a large diameter and thin struts are associated with better image quality and higher diagnostic accuracy.

[A new method for purification and identification of hepatocellular carcinoma stem cell of SMMC-7721].

OBJECTIVE: To explore a new efficient purification method of hepatocellular carcinoma (HCC) stem cells and identify their features. METHODS: Human hepatocellular carcinoma cell line SMMC-7721 was cultured in sphere-culture system of polyhedra-treated dish and tumor stem cell specific medium. Upon the formation of cellular sphere, the cells were inoculated subcutaneously into immunocompromised mice and received the interventions of different concentrations of cisplatin. Then the drug-resistant cells were purified and re-cultured in TSC medium. Finally the stem cell markers and tumor stem cell markers were determined through real-time polymerase chain reaction (PCR), immunofluorescence method and flow cytometry. RESULTS: Through the double filter of TSC medium and cisplatin-resistance, SMMC-7721 stem cells could be grown in a suspended form and formed spheres in TSC medium. The stem cell markers (NANOG, OCT-4, SOX-2 and Notch) and tumor stem cell markers (CD24, 90.0%; CD133, 6.1%; CD90, 4.8%) were all over-expressed in purified cancer stem cells as compared with ordinary cells. And the over-expression of CD24 was the most obvious. CONCLUSIONS: The combination of in vitro cell culture with TSC medium, in vivo proliferation and cisplatin resistance test is a new efficient method of purifying hepatocellular carcinoma stem cells. Tumor stem cell with stem cell characteristics and an over-expression of CD24 may be cloned from SMMC-7721.

[Geographical characteristics of single nucleotide polymorphism of candidate genes associated with coronary artery disease in Chinese Han population].

OBJECTIVE: To investigate the geographical characteristics of single nucleotide polymorphism (SNP) of candidate genes associated with coronary artery disease in Chinese Han population. METHODS: Study population were Chinese Han nationality recruited from Xi'an, Shiyan and Ningbo districts. Patients with coronary artery disease were defined by coronary angiography with stenosis >or= 50% and control subjects with stenosis < 10%, respectively. The DNA was extracted from peripheral white blood cell by approach comprised proteinase K digestion, phenol and chloroform extraction as well as isopropanol precipitation. The SNP of ATP-binding cassette transporter (ABCA1)-G596A, cholesteryl ester transfer protein (CETP)-Taq1B, Lipoprotein lipase (LPL)-Hind III and LPL-Pvu II were genotyped by PCR-RFLPs, and verified by gene sequencing. RESULTS: A Total of 615 patients undertaken coronary angiography were recruited from cardiac center in Xi'an (220), Ningbo (209) and Shiyan district (186), China (mean age 60 +/- 10 years, 75.9% males). Diabetes mellitus was more prevalent in Xi'an Cohort population than Shiyan and Ningbo cohort (P < 0.01). Plasma total cholesterol, LDL cholesterol and triglyceride levels in Xi'an Cohort population were significantly higher, and HDL-C siginificantly lower than in Shiyan and Ningbo cohort population [HDL-C: (1.17 +/- 0.48) mmol/L vs. (1.25 +/- 0.33) mmol/L and (1.29 +/- 0.44) mmol/L, P < 0.05]. Distribution differences for ABCA1-G596A and CETP-Taq1B genotypes were found in Xi'an Cohort population compared to Ningbo and Shiyan cohorts (for ABCA1, Xi'an: 0.24, 0.53, 0.23 and Shiyan: 0.17, 0.62, 0.21 and Ningbo: 0.34, 0.37, 0.29, for GG, AG, AA, respectively, P < 0.01; and for CETP, Xi'an: 0.29, 0.54, 0.17 and Shiyan: 0.38, 0.40, 0.22 and Ningbo: 0.39, 0.49, 0.12 for B1B1, B1B2, B2B2, respectively, P < 0.01), but not for LPL variants. ABCA1-G596A variant predicted HDL-C [Xi'an: (1.2 +/- 0.3) mmol/L, (1.3 +/- 0.2) mmol/L and (1.4 +/- 0.4) mmol/L, P = 0.01; Shiyan: (1.1 +/- 0.4) mmol/L: (1.2 +/- 0.3) mmol/L and (1.3 +/- 0.4) mmol/L, P = 0.03; Ningbo, (1.2 +/- 0.3) mmol/L, (1.3 +/- 0.4) mmol/L and (1.4 +/- 0.3) mmol/L, across GG, GA to AA genotype, respectively, P = 0.01] and TG levels [Xi'an: (2.4 +/- 1.3) mmol/L, (1.9 +/- 0.9) mmol/L and (1.6 +/- 0.8) mmol/L, P < 0.01; Shiyan: (2.1 +/- 1.0) mmol/L, (1.9 +/- 0.8) mmol/L and (1.8 +/- 0.7) mmol/L, P = 0.03; Ningbo: (1.9 +/- 1.1) mmol/L, (1.8 +/- 0.9) mmol/L and (1.6 +/- 0.7) mmol/L, across GG, GA to AA genotype, P = 0.05] with dose-dependent relationship. LPL-Hind III (+) carriers had higher triglycerides in three cohort population [Xi'an: (2.2 +/- 1.0) mmol/L, (1.8 +/- 0.9) mmol/L, (1.6 +/- 0.7) mmol/L, P = 0.01; Shiyan: (2.1 +/- 0.7) mmol/L, (1.9 +/- 1.0) mmol/L, (1.7 +/- 0.6) mmol/L, P = 0.01; Ningbo: (1.8 +/- 1.0) mmol/L, (1.6 +/- 0.6) mmol/L and (1.4 +/- 0.5) mmol/L, for +/+, +/- and -/- genotypes, respectively, P = 0.001]. SNP of CETP-Taq1B, LPL-Hind III and LPL-Pvu II predicted HDL-C and/or TG levels in different cohort population with different manners. All these SNP were not significantly associated with the development of coronary artery disease (all P > 0.05). CONCLUSION: A geographical heterogeneity of environmental and genetic risk factors related to the development of coronary artery disease exists in Chinese Han population. Irrespective of the different geographical cohort of Chinese Han population, the SNP of candidate genes can partly predict the differences in risk-related plasma HDL-C and/or TG levels rather than angiographic coronary artery disease.

Modified classic risk factors for coronary artery disease in Chinese Han population.

OBJECTIVE: To investigate the levels of cardiovascular disease risk factors and their relations to clinical phenotype associated with coronary artery disease (CAD). METHODS: The subjects were recruited from five independent cardiovascular centers. Coronary angiography was employed to define the CAD with stenosis in each major vessel > or = 70% and control with stenosis < 10% in every lesion. The classic risk factors including family history, body mass index, smoking habits, hypertension, diabetes mellitus, and serum lipid levels were surveyed according to established criteria. Associations between risk levels and clinical phenotypes were assessed by case control and correlation analysis. RESULTS: A total of 762 individuals were collected, including 481 men and 281 women, aged from 17 to 81 (mean 60 +/- 10) years. The patients with CAD accounted for 55.5% of all participants, and controls 44.5%, respectively. Compared with the pattern in published data, our study showed that mean serum high density lipoprotein cholesterol (HDL-C) level was significantly lower (P < 0.001) and triglycerides was significantly higher (P < 0.001), while total cholesterol (TC) and low density lipoprotein cholesterol levels were comparative (both P > 0.05). The prevalence of low HDL-C (< 40 g/L) and hypertriglyceridemia (> 150 g/L) were 27.2% and 41.4%, respectively. Mean serum levels of HDL-C and apolipoprotein A1 were significantly higher in female subjects than in male (P < 0.001). Lower HDL-C functioned as an independent risk factor for CAD only in men (RR = 2.8, 95% CI: 1.5-4. 2, P < 0.001), yet increased non-HDL cholesterol combined with diabetes mellitus and obesity seemed to play a key role in the development of CAD in women. Similarity in risk association with CAD was found for hypertension and TC/HDL ratio in male and female subjects, while family history had no relationship with the presence of CAD. CONCLUSION: It is remarkable that emphasis of intervention in future should be given on the prevalent low serum HDL-C and its strong risk correlation with the presence of CAD in male subjects of Chinese Han population.

Prevention of pericardial constriction by transcatheter intrapericardial fibrinolysis with urokinase.

OBJECTIVE: To investigate whether intrapericardial urokinase irrigation along with pericardiocentesis could prevent pericardial constriction in patients with infectious exudative pericarditis. METHODS: A total of 94 patients diagnosed as infectious exudative pericarditis (34 patients with purulent pericarditis and 60 with tuberculous pericarditis, the disease courses of all patients were less than 1 month), 44 males and 50 females, aged from 9 to 66 years (mean 45.4 +/- 14.7 years), were consecutively recruited from 1993 to 2002. All individuals were randomly given either intrapericardial urokinase along with conventional treatment in study group, or conventional treatment alone (including pericardiocentesis and drainage) in control group. The dosage of urokinase ranged from 200000 to 600000 U (mean 320000 +/- 70000 U). The immediate effects were detected by pericardiography with sterilized air and diatrizoate meglumine as contrast media. The long-term investigation depended on the telephonic survey and echocardiographic examination. The duration of following-up ranged from 8 to 120 months (mean 56.8 +/- 29.0 months). RESULTS: Percutaneous intrapericardial urokinase irrigation promoted complete drainage of pericardial effusion, significantly reduced the thickness of pericardium (from 3.1 +/- 1.6 mm to 1.6 +/- 1.0 mm in study group, P < 0.001; from 3.4 +/- 1.6 mm to 3.2 +/- 1.8 mm in control group, P > 0.05, respectively), and alleviated the adhesion. Intrapericardial bleeding related to fibrinolysis was found in 6 of 47 patients with non-blood pericardial effusion and no systemic bleeding and severe puncture-related complication was observed. In follow-up, there was no cardiac death, and pericardial constriction events were observed in 9 (19.1%) of study group and 27 (57.4%) of control group. Cox analysis illustrated that urokinase could significantly reduce the occurrence of pericardial constriction (relative hazard coefficient = 0.185, P < 0.0001). CONCLUSION: The early employment of intrapericardial fibrinolysis with urokinase and pericardiocentesis appears to be safe and effective in preventing the development of pericardial constriction in patients with infectious exudative pericarditis.

[Single nucleotide polymorphisms of genes associated with high density lipoprotein metabolism in Chinese population].

OBJECTIVE: To study the single nucleotide polymorphisms in genes associated with the high density lipoprotein (HDL) metabolism in Chinese population. METHODS: Two hundred and nine normal Han ethnic subjects, aged 59+/-10 years, were recruited from 5 medical centers in western part of China. DNA was extracted by proteinase K digestion, phenol and chloroform extraction as well as isopropanol precipitation. The polymerase chain reaction (PCR)-restriction fragment length polymorphisms (RFLP) in conjunction with sequencing were employed to test the single nucleotide polymorphisms (SNPs) in ATP-binding cassette transporter (ABCA1), cholesteryl ester transfer protein (CETP) and lipoprotein lipase (LPL) genes. RESULTS: The allelic frequencies of A and G of ABCA1 gene are 53.4% and 46.6%; of B2 and B1 allele of CETP, 41.0% and 59.0%; of HindIII (-) and (+) allele of LPL, 18.9% and 81.1%; and of PvuII(+) and (-) allele of LPL, 66.0% and 34.0%, respectively. All genotype frequencies fit well with the Hardy-Weinberg equilibrium; the significant linkage disequilibrium exists between LPL HindIII(+)and PvuII(+) polymorphisms. All of the RFLP in these genes result from the single nucleic substitution in fragment recognized by corresponding restriction enzymes. CONCLUSION: The genetic polymorphisms of ABCA1, LPL-HindIII and LPL-PvuII in Chinese Han ethnic population are significantly different from Caucasians residing in USA or Europe.