Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with v...Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with vasospastic angina, with one of which presenting with sudden cardiac arrest, while the other presenting with a relatively benign syncope. But both of them have J waves formation on ECG during active ischemia. The diagnosis and management of vasospastic angina, as well as the proposed clinical significance of J waves during coro- nary soasm are discussed.展开更多
Objective The -455 G/A(HaeIII)polymorphism of β-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of ischemic cerebrovascular disease. Methods We accumulat...Objective The -455 G/A(HaeIII)polymorphism of β-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of ischemic cerebrovascular disease. Methods We accumulated 134 acute ischemic cerebrovascular disease(ICVD)cases and compared their -455 G/A status with a control group(n = 166). The β-fibrinogen gene -455 G/A polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme HaeIII. Results Plasma fibrinogen was higher in AA homozygous participants(341 mg/dL)than in partici-pants carrying the G allele: GA(290 mg/dL), GG(298 mg/dL)in the control group. Plasma fibrinogen was also higher in AA homozygous patients(353 mg/dL)than in cases carrying the G allele: GA(287 mg/dL), GG(302 mg/dL)in the ICVD group. However, there was no significant association between β-fibrinogen gene -455 G/A polymorphism and ICVD group. Conclusions Although a small effect cannot be excluded, β-fibrinogen gene -455 G/A polymor-phism is an independent predictor of plasma fibrinogen, but not of ischemic cerebrovascular disease.展开更多
AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infe...AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis B infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis B virus （HBV） infection were classified into three groups： past hepatitis, ＂anti-HBc alone＂ and chronic hepatitis. Determination of DNA from HBV, and RNA and genotype from hepatitis C virus （HCV） were performed on ＂anti-HBc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HBV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-HBc alone＂ （29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （Cl） 1.33-4.00] and antibodies to HCV infection [odds ratio （OR） 2.87; 95% CI 1.10-7.48] were factors independently associated with the ＂anti-HBc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-HBs were not associated with HCV infection （nor viral replication or HCV genotype）, or with HIV replication or CD4 level. No ＂anti-HBc alone＂ patient tested positive for HBV DNA. CONCLUSION： ＂Anti-HBc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HCV infection. In clinical practice, HBV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,展开更多
The generalized linear model is an indispensable tool for analyzing non-Gaussian response data, with both canonical and non-canonical link functions comprehensively used. When missing values are present, many existing...The generalized linear model is an indispensable tool for analyzing non-Gaussian response data, with both canonical and non-canonical link functions comprehensively used. When missing values are present, many existing methods in the literature heavily depend on an unverifiable assumption of the missing data mechanism, and they fail when the assumption is violated. This paper proposes a missing data mechanism that is as generally applicable as possible, which includes both ignorable and nonignorable missing data cases, as well as both scenarios of missing values in response and covariate.Under this general missing data mechanism, the authors adopt an approximate conditional likelihood method to estimate unknown parameters. The authors rigorously establish the regularity conditions under which the unknown parameters are identifiable under the approximate conditional likelihood approach. For parameters that are identifiable, the authors prove the asymptotic normality of the estimators obtained by maximizing the approximate conditional likelihood. Some simulation studies are conducted to evaluate finite sample performance of the proposed estimators as well as estimators from some existing methods. Finally, the authors present a biomarker analysis in prostate cancer study to illustrate the proposed method.展开更多
基金grants from the National Nat-ural Science Foundation of China，the PhD Programs Foundation of Ministry of Education of China (20120001120131). The authors of this article do not have potential conflicts of interest
文摘Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with vasospastic angina, with one of which presenting with sudden cardiac arrest, while the other presenting with a relatively benign syncope. But both of them have J waves formation on ECG during active ischemia. The diagnosis and management of vasospastic angina, as well as the proposed clinical significance of J waves during coro- nary soasm are discussed.
文摘Objective The -455 G/A(HaeIII)polymorphism of β-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of ischemic cerebrovascular disease. Methods We accumulated 134 acute ischemic cerebrovascular disease(ICVD)cases and compared their -455 G/A status with a control group(n = 166). The β-fibrinogen gene -455 G/A polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme HaeIII. Results Plasma fibrinogen was higher in AA homozygous participants(341 mg/dL)than in partici-pants carrying the G allele: GA(290 mg/dL), GG(298 mg/dL)in the control group. Plasma fibrinogen was also higher in AA homozygous patients(353 mg/dL)than in cases carrying the G allele: GA(287 mg/dL), GG(302 mg/dL)in the ICVD group. However, there was no significant association between β-fibrinogen gene -455 G/A polymorphism and ICVD group. Conclusions Although a small effect cannot be excluded, β-fibrinogen gene -455 G/A polymor-phism is an independent predictor of plasma fibrinogen, but not of ischemic cerebrovascular disease.
文摘AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis B infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis B virus （HBV） infection were classified into three groups： past hepatitis, ＂anti-HBc alone＂ and chronic hepatitis. Determination of DNA from HBV, and RNA and genotype from hepatitis C virus （HCV） were performed on ＂anti-HBc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HBV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-HBc alone＂ （29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （Cl） 1.33-4.00] and antibodies to HCV infection [odds ratio （OR） 2.87; 95% CI 1.10-7.48] were factors independently associated with the ＂anti-HBc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-HBs were not associated with HCV infection （nor viral replication or HCV genotype）, or with HIV replication or CD4 level. No ＂anti-HBc alone＂ patient tested positive for HBV DNA. CONCLUSION： ＂Anti-HBc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HCV infection. In clinical practice, HBV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,
基金supported by the Chinese 111 Project B14019the US National Science Foundation under Grant Nos.DMS-1305474 and DMS-1612873the US National Institutes of Health Award UL1TR001412
文摘The generalized linear model is an indispensable tool for analyzing non-Gaussian response data, with both canonical and non-canonical link functions comprehensively used. When missing values are present, many existing methods in the literature heavily depend on an unverifiable assumption of the missing data mechanism, and they fail when the assumption is violated. This paper proposes a missing data mechanism that is as generally applicable as possible, which includes both ignorable and nonignorable missing data cases, as well as both scenarios of missing values in response and covariate.Under this general missing data mechanism, the authors adopt an approximate conditional likelihood method to estimate unknown parameters. The authors rigorously establish the regularity conditions under which the unknown parameters are identifiable under the approximate conditional likelihood approach. For parameters that are identifiable, the authors prove the asymptotic normality of the estimators obtained by maximizing the approximate conditional likelihood. Some simulation studies are conducted to evaluate finite sample performance of the proposed estimators as well as estimators from some existing methods. Finally, the authors present a biomarker analysis in prostate cancer study to illustrate the proposed method.
