Association between serum uric acid levels and achievement of target blood pressure among Japanese community residents with hypertension

The authors examined the sex-specific association between serum uric acid (SUA) levels and achievement of target blood pressure among Japanese patients with hypertension. This cross-sectional study was conducted between January 2012 and December 2015 and examined 17 113 eligible participants (6499 men; 10 614 women) with hypertension among 66 874 Japanese community residents who underwent voluntary health checkups. Multivariate analysis was used to estimate the association between high SUA level (≥7.0 mg/dL for men and ≥6.0 mg/dL for women) and "therapeutic failure" in achieving target blood pressure (BP) of 140/90 and 130/80 mmHg in both sexes. Multivariate analysis revealed that high SUA level was significantly associated with failure to achieve the 130/80 mmHg treatment goal among men (AOR = 1.24, 95% CI = 1.03-1.50, p = .03). Among women, high SUA level was significantly associated with failure to achieve both the 130/80 and 140/90 mmHg treatment goals (AOR = 1.33, 95% CI = 1.20-1.47, p < .01 and AOR = 1.17, 95% CI = 1.04-1.32, p < .01, respectively). Each increase in SUA quartile was positively associated with increases in systolic BP (SBP) and diastolic BP (DBP) (p < .01 for trend) in both sexes. SBP and DBP in each quartile (Q2-Q4) were also significantly higher compared with those of Q1 in both sexes (p < .01). Our data confirms the difficulties in maintain goal BP control in those with elevated SUA.

Efficacy and safety of semaglutide in glycemic control, body weight management, lipid profiles and other biomarkers among obese type 2 diabetes patients initiated or switched to semaglutide from other GLP-1 receptor agonists

Purpose

Evidence of the efficacy and safety of semaglutide among patients with type 2 diabetes who were initiated on or were switched to semaglutide from other GLP-1 RAs remains limited. The objective of this study was to investigate the short-term effects of switching to semaglutide from other GLP-1 RAs.

Methods

This retrospective cohort study evaluated patients with type 2 diabetes who were initiated on or were switched to semaglutide due to poor diabetes control with other GLP-1 RAs or other medications, or obesity. HbA1c, body weight, serum creatinine, serum uric acid, parameters of lipid metabolism, and parameters of liver function were measured before and 6 months after administration of semaglutide.

Results

A total of 50 patients were registered in the study. After switching to semaglutide (n = 43), HbA1c and body weight significantly decreased (p < 0.01, p < 0.01), respectively. The same findings were observed in semaglutide-naïve patients (p = 0.04, p < 0.02) (n = 7). Serum uric acid, total cholesterol, triglycerides, and urinary albumin-creatinine ratio decreased significantly as well (p = 0.04, p = 0.04, p = 0.02, p = 0.04), whereas serum creatinine did not change significantly (p = 0.51).

Conclusions

Semaglutide showed excellent efficacy, even in patients switched from other GLP-1 RAs. Semaglutide appears to be a promising agent for blood glucose and body weight control in obese type 2 diabetes mellitus patients and could be more potent in treating type 2 diabetes than existing GLP-1 RAs.

An association between subcutaneous fat mass accumulation and hypertension

Evidence to assess relationships between subcutaneous fat area (SFA) and lifestyle-related diseases, including hypertension, remains limited. The aim of this study was to investigate the relationship between SFA and hypertension. This study was a single-institution, cross-sectional study of 1,899 eligible Japanese participants who underwent health checkups between December 2016 and December 2018. All patients were measured for SFA and visceral fat area (VFA) by abdominal computed tomography (CT). SFA was divided into quartiles by gender, and multivariate logistic regression analysis was performed to estimate associations between SFA quartiles (Q) and hypertension. Mean age and SFA were 60.9 9 (standard devastation [SD]:12.0) years and 123.0 (56.9) cm2 in men, and 60.6 (12.8) years and 146.6 (79.0) cm2 in women, respectively. Risk of hypertension from multivariate regression modeling compared with the lowest quartile (Q) in both sexes was as follows: for men Q2 [odds ratio (OR), 1; 95% confidence interval (CI), 0.55-1.51 ], Q3 (OR, 1.73; 95%CI, 1.17-2.56), and Q4 (OR, 1.96; 95%CI, 1.31-2.94); for women Q2 (OR, 0.87; 95%CI, 0.48-1.58), Q3 (OR, 1.73; 95%CI, 1.02-2.95), and Q4 (OR, 2.54; 95%CI, 1.51-4.28). The optimal SFA cutoff value at risk of hypertension was 114.7 cm2 in men and 169.3 cm2 in women. The prevalence of hypertension was positively associated with SFA quartiles in both genders. The present results may indicate the necessity of considering not only VFA, but also SFA for the primary and secondary prevention of hypertension.

An association between visceral or subcutaneous fat accumulation and diabetes mellitus among Japanese subjects

BACKGROUND

The impact of subcutaneous fat accumulation remains controversial. This study assessed the association between visceral or subcutaneous fat area (VFA and SFA, respectively) and diabetes mellitus (DM) among Japanese subjects.

METHODS

This was a cross-sectional study involving 1907 eligible participants (men, 1050; women, 857) who participated in a voluntary health check-up conducted at Juntendo University Hospital from January 2017 to December 2018, in Tokyo, Japan. Associations between VFA or SFA quartiles and DM were identified using adjusted odds ratios (AORs) and 95% confidence intervals (CIs) with multivariable logistic regression analysis adjusted for confounders. Receiver operating characteristic (ROC) curve analysis was used to assess appropriate cut-off values of VFA or SFA.

RESULTS

Multivariate analyses showed that Q4 (≥ 125 cm²) of VFA was significantly positively associated with DM compared to Q1 (< 65 cm²) (AOR = 1.94, 95% CI 1.02-3.71), whereas there was no association between SFA and DM in men. Among women, Q4 (≥ 85 cm²) of VFA was significantly positively associated with DM compared to Q1 (< 30 cm²) (Q4, AOR = 6.15, 95% CI 1.65-22.99). Also, Q3 and Q4 (≥ 135 cm²) of SFA were significantly positively associated with DM compared to Q1 (< 90 cm²) (Q3, AOR = 5.64, 95% CI 1.21-26.25; Q4, AOR = 7.81, 95% CI 1.71-35.65). The appropriate cut-off value of VFA in men was 101.5 cm². Those of VFA and SFA in women were 72.5 cm² and 165.3 cm², respectively.

CONCLUSIONS

Our results suggest the importance of considering SFA as well as VFA, especially in women, for primary and secondary prevention of DM.

Serum zinc concentrations and characteristics of zinc deficiency/marginal deficiency among Japanese subjects

BACKGROUND

Studies that have examined serum zinc deficiency/marginal deficiency in developed countries, including Japan, are still limited. The aim of this study was to assess serum zinc concentrations and associated characteristics among Japanese subjects.

METHODS

This cross-sectional study, conducted from September 2016 to December 2018, included 2056 eligible subjects who participated in a voluntary health checkup. Serum zinc concentration categories were defined as deficiency (<60 μg/dL), marginal deficiency (≥60 to <80 μg/dL), and normal (≥80 μg/dL). Serum zinc concentrations were compared between the first age category (<40 years) and other age categories with Dunnett's method. Trends in P-values were estimated using the Jonckheere-Terpstra test for continuous variables.

RESULTS

The proportions of subjects with deficiency and marginal deficiency were 0.4% and 46.0% in men, and 0.6% and 38.4% in women, respectively. The deficiency/marginal deficiency group had significantly lower lipid profiles and nutritional status, and a significantly lower proportion were non-daily drinkers in both genders. Older age was significantly associated with lower serum zinc concentration only in men.

CONCLUSIONS

Our findings clarified a high proportion of serum zinc deficiency/marginal deficiency, especially in men, and suggest a possible association between serum zinc levels and nutritional status and alcohol consumption. It may be necessary to manage nutritional status, including zinc intake.

Assessing lifestyle-related diseases with body and muscle mass using bioelectrical impedance analysis

Objectives

To investigate the correlation between imbalance of muscle mass to body weight and lifestyle-related diseases using bioelectrical impedance analysis (BIA) among Japanese population.

Methods

This was a retrospective, cross-sectional study conducted at Juntendo University Hospital in Tokyo, Japan, from May 2015 to November 2017. Their muscle-to-weight ratio were stratified into “muscle-to-weight ratio” quartiles as follows: men, Q1 (≥0.79), Q2 (0.75 to <0.79), Q3 (0.72 to <0.75), and Q4 (<0.72); women, Q1 (≥0.73), Q2 (0.68 to <0.73), Q3 (0.63 to <0.68), and Q4 (<0.63). The primary outcome was prevalence of ≥2 lifestyle-related diseases, including hypertension, dyslipidemia, type 2 diabetes mellitus, and hyperuricemia.

Results

Data from 2009 individuals (men, 55%; mean age, 62 years) were analyzed. Compared to the lowest quartile, risk for the presence of ≥2 lifestyle-related diseases, in a multivariable regression model for men was as follows: Q2 (odds ratio [OR], 1.93; 95% confidence interval [CI], 1.31–2.87), Q3 (OR, 2.85; 95% CI, 1.89–4.29), and Q4 (OR, 6.00; 95% CI, 4.07–8.84). For women, an increased risk was seen in Q2 (OR, 2.31; 95% CI, 1.20–4.46), Q3 (OR, 4.45; 95% CI, 2.40–8.26), and Q4 (OR, 12.6; 95% CI, 6.80–23.5). Cutoff values of muscle-to-weight ratio correlated with lifestyle-related diseases (≥2) were 0.76 for men and 0.68 for women.

Conclusions

Our results showed that an imbalance of muscle mass to body weight confers an independent and stepwise increased risk for lifestyle-related diseases.

Achievement of Target Serum Uric Acid Levels and Factors Associated with Therapeutic Failure among Japanese Men Treated for Hyperuricemia/Gout

Objective To assess the rate of successfully achieving treatment goals among Japanese men with hyperuricemia/gout and identify factors influencing the success rate. Methods This cross-sectional study, conducted from January to December 2012, examined the serum uric acid (SUA) levels and clinical characteristics of 2,103 men with hyperuricemia/gout selected from an initial population of 136,770 individuals who participated in a workplace health checkup. The success rates (defined as SUA ≤6.0 mg/dL) were calculated, and a multivariate analysis was used to identify factors associated with "therapeutic failure" to achieve target SUA levels. Results The rate of successfully achieving the target SUA level was 37.5%. The body mass index (BMI) was significantly associated with therapeutic failure [25.0≤ Category (C) 2<27.5, adjusted odds ratio (AOR) =1.35; 27.5≤C3<30.0, AOR=1.69; C4 ≥ 30.0, AOR=1.94; relative to C1<25.0]. A significant positive association was also observed between waist circumference (WC) and therapeutic failure (85≤C2<90, OR=1.29; 90≤C3<95, OR=1.41; 95≤C4, OR=2.28; relative to C1<85.0 cm). Those with higher BMI/WC measurements were significantly more likely to have higher SUA levels than those with lower such measurements. The ongoing intake of dyslipidemia medication was identified as a protective factor against therapeutic failure. Discussion Our findings suggest a possible association between obesity and therapeutic failure, underscoring the importance of maintaining lipid profiles as part of managing SUA levels. Better management of both obesity and dyslipidemia may prevent future cardiovascular disorders by ensuring healthier SUA levels.

Association between high cystatin C levels and carotid atherosclerosis

AIM

To investigate the association between carotid atherosclerosis and cystatin C (CysC) and to determine the optimal CysC cut-off value.

METHODS

One hundred twenty-eight subjects were included in this study. Atherosclerosis was defined as a maximum carotid plaque thickness (MCPT) of greater than 2 mm. A receiver operating characteristic curve analysis was used to determine the diagnostic value of serum CysC for atherosclerosis. The subjects were divided into two groups according to the CysC cut-off value. We screened for diabetes, hypertension, dyslipidemia, smoking status, alcohol consumption, and exercise behavior. The association between atherosclerosis and CysC levels was assessed using multivariate analysis.

RESULTS

The subjects were then divided into two groups according to the CysC cut-off value (0.73 mg/L). The median age of the high CysC group was 72 years (85% males), whereas that of the low CysC group was 61 years (63% males). The CysC levels were significantly correlated with Cr and estimated glomerular filtration rate (eGFR) values. Body-mass index, visceral fat area, hypertension, diabetes mellitus, and MCPT were significantly higher in the high CysC group than in the low CysC group. Furthermore, the eGFR was significantly lower in the high CysC group. Regarding lifestyle habits, only the exercise level was lower in the high CysC group than in the low CysC group. Multivariate analysis, adjusted for age and sex, revealed that high CysC levels were significantly associated with an MCPT of ≥ 2 mm (odds ratio: 2.92; 95%CI: 1.13-7.99).

CONCLUSION

Higher CysC levels were associated with an MCPT of ≥ 2 mm. The CysC cut-off value of 0.73 mg/L appears to aid in the diagnosis of atherosclerosis.

Bacteraemia predictive factors among general medical inpatients: a retrospective cross-sectional survey in a Japanese university hospital

OBJECTIVES

The precise criteria for obtaining blood cultures have not been established; they depend on the physician's judgement. We examined clinical parameters to determine predictive factors of bacteraemia and the need for blood cultures among general medical inpatients.

DESIGN

A retrospective cross-sectional survey.

SETTING

A Japanese university hospital.

PARTICIPANTS

All general inpatients who had blood cultures taken from 1 January 2011 to 31 December 2012.

MAIN MEASURES

Clinical information at or just before blood culture sampling was extracted from medical charts. Factors potentially predictive of bacteraemia were analysed using Fisher's exact test, followed by multivariable logistic regression model analysis.

MAIN RESULTS

A total of 200 patients (male: female=119:81, 64.3±19.1 years old) comprised this study; 57 (28.5%) had positive blood culture results. Multivariable logistic regression analysis revealed that age >60 years (OR=2.75, 95% CI 1.23 to 6.48, p=0.015), female sex (OR=2.21, 95% CI 1.07 to 4.67, p=0.038), pulse rate >90 bpm (OR=5.18, 95% CI 2.25 to 12.48, p<0.001) and neutrophil percentage >80% (OR=3.61, 95% CI 1.71 to 8.00, p=0.001) were independent risk factors for positive blood culture results. The area under the receiver operating characteristic curve analysis of this model was 0.796.

CONCLUSIONS

Our results emphasise the importance of taking blood cultures if the pulse rate is >90 bpm, in elderly patients and in women, and for ordering a differential white cell count.

The Relationships between Metabolic Disorders (Hypertension, Dyslipidemia, and Impaired Glucose Tolerance) and Computed Tomography-Based Indices of Hepatic Steatosis or Visceral Fat Accumulation in Middle-Aged Japanese Men

Background

Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA.

Methods

The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm² at the level of the navel. Metabolic disorders were defined using Japan’s metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups.

Results

Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01).

Conclusions

It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are needed to reveal the relationships between the components of metabolic disorders and HS/VFA.

Association between health literacy and metabolic syndrome or healthy lifestyle characteristics among community-dwelling Japanese people

BACKGROUND

Few studies have assessed the association between health literacy (HL) and healthy lifestyle characteristics among Japanese people, and reports on the association between HL and prevalence of metabolic syndrome are also scarce.

METHODS

The present cross-sectional study included 1817 (781 men and 1036 women) Japanese individuals who participated in a medical health checkup at Bange Kosei General Hospital and Takada Kosei Hospital in Fukushima, Japan, from April 2013-2014. Information regarding HL and healthy lifestyle characteristics listed in Breslow's seven health practices was collected by self-administered questionnaire.

RESULTS

In multivariate logistic analysis, higher HL (≥14) was positively associated with healthy lifestyle characteristics [odds ratio (OR) = 2.08, 95 % confidence interval (CI) = 1.33-3.23] and inversely associated with prevalence of metabolic syndrome (OR = 0.67, 95 % CI = 0.48-0.95) among men. Among HL items, the ability to make decisions based on health-related information was significantly associated with healthy lifestyle characteristics (OR = 2.04, 95 % CI = 1.34-3.10 for men, OR = 1.38, 95 % CI = 1.30-1.85 for women) and inversely associated with prevalence of metabolic syndrome (OR = 0.62, 95 % CI = 0.44-0.88 for men, OR = 0.68, 95 % CI = 0.49-0.95 for women) in both sexes.

CONCLUSIONS

We found positive associations between HL and healthy lifestyle characteristics and an inverse association with prevalence of metabolic syndrome among men. Our findings also suggest that men and women are likely to engage in health-promoting behaviors and make decisions based on health-related information. These findings highlight the importance of comprehensive assessments, including HL, for health promotion in the community.

Achievement of Target Blood Pressure Levels among Japanese Workers with Hypertension and Healthy Lifestyle Characteristics Associated with Therapeutic Failure

BACKGROUND

Few studies have examined Japanese with regard to the achievement rates for target blood pressure levels, or the relationship between these rates and healthy lifestyle characteristics in patients with hypertension as defined by the newly established hypertension management guidelines (JSH2014). The aim of this study was to elucidate achievement rates and examine healthy lifestyle characteristics associated with achievement status among Japanese.

METHODS

This cross-sectional study, conducted in January-December 2012, examined blood pressure control and healthy lifestyle characteristics in 8,001 Japanese workers with hypertension (mean age, 57.0 years; 78.8% were men) who participated in a workplace health checkup. Data were collected from workplace medical checkup records and participants' self-administered questionnaires. We divided into 5 groups [G1; young, middle-aged, and early-phase elderly patients (65-74 years old) without diabetes mellitus or chronic kidney disease (CKD) (<140/90 mmHg), G2; late-phase elderly patients (≥75 years old) without diabetes mellitus or CKD (<150/90 mmHg), G3; diabetic patients (<130/80 mmHg), G4; patients with CKD (<130/80 mmHg), and G5; patients with cerebrovascular and/or coronary artery diseases (<140/90 mmHg)] according to JSH2014. And then, achievement rates were calculated in each group. Multivariate analysis identified healthy lifestyle characteristics associated with "therapeutic failure" of target blood pressure.

RESULTS

Target blood pressures were achieved by 60.2% of young, middle-aged, and early-phase elderly patients (G1), 71.4% of late-phase elderly patients (G2), 30.5% of diabetic patients (G3), 33.4% of those with chronic kidney disease (G4), and 66.0% of those with cerebrovascular and/or coronary artery diseases (G5). A body mass index of 18.5-24.9 and non-daily alcohol consumption were protective factors, and adequate sleep was found to contribute to therapeutic success.

DISCUSSION

We found low achievement rates for treatment goals among patients with chronic kidney disease and diabetes mellitus. Maintaining an ideal body weight and adequate alcohol consumption may help with blood pressure control. Lifestyle modification may be necessary for better management of hypertension.

Association Between Serum Uric Acid Levels/Hyperuricemia and Hypertension Among 85,286 Japanese Workers

This cross-sectional study from January 2012 to December 2012 aimed to examine the sex-specific association between serum uric acid (SUA) levels/hyperuricemia and hypertension among Japanese patients. SUA level, medical histories, and lifestyle-related items were collected from 85,286 of 136,770 participants. Among those with hyperuricemia, the median age was 46 years and 97% were men, which was significantly different than those without hyperurecemia (44 years and 56%, respectively; P<.01). Hyperuricemia was 1.79 times more likely in hypertensive men than normotensive men and almost six times more likely in hypertensive women (odds ratio=5.92 and adjusted odds ratio=1.33 for men and adjusted odds ratio=1.81 for women) after multivariate analysis. SUA quartiles positively correlated with systolic and diastolic blood pressures in both sexes. Hyperuricemia and SUA levels were significantly associated with hypertension in both sexes. These findings underscore the importance of maintaining normal SUA levels to manage and prevent hypertension. Better management of SUA as well as blood pressure may have potential in preventing future cardiovascular disorders.

Utility of 75-g oral glucose tolerance test results and hemoglobin a1c values for predicting the incidence of diabetes mellitus among middle-aged Japanese men -a large-scale retrospective cohort study performed at a single hospital

OBJECTIVE

The aim of this study was to investigate the associations between the incidence of diabetes and the accumulation of markers of impaired glucose metabolism; i.e., pre-diabetes.

METHODS

This retrospective cohort study recruited 1,631 men without diabetes at baseline who attended more than two routine health check-ups at our institution between 2006 and 2012. The participants were divided into four groups based on the number of markers of impaired glucose metabolism exhibited at the initial examination. The following markers of impaired glucose metabolism were defined as risk factors for diabetes: a fasting plasma glucose level of ≥110 mg/dL, 2-hour plasma glucose level of ≥140 mg/dL and glycated hemoglobin (HbA1c) value of ≥6.0% (42 mmol/moL). The risk of developing diabetes was assessed using a multivariate analysis.

RESULTS

The median examination interval was 1,092 days. The incidence of diabetes rose in association with the number of markers. The subjects with two markers displayed a multivariate-adjusted odds ratio (OR) for diabetes of 19.43 [95% confidence interval (CI): 9.70-38.97] and the subjects with three markers displayed an OR of 48.30 (95% CI: 20.39-115.85) compared with the subjects with one or no markers.

CONCLUSION

The present results demonstrate the impact of accumulating markers of impaired glucose metabolism on the risk of developing diabetes. Anti-diabetes intervention strategies should aim to comprehensively assess an individual's risk of developing diabetes at the pre-diabetes stage.

Age-specific effectiveness and safety of newly initiated insulin therapy in Japanese patients with uncontrolled diabetes

INTRODUCTION

One consequence of population aging is an increase in the number of elderly patients with diabetes mellitus. These elderly patients often experience atherosclerotic complications, and diabetes prevention and management are strongly desired to promote health and reduce the financial burden on the healthcare system. In this study, we conducted an age-specific evaluation of the effectiveness and safety of comprehensive management with newly initiated insulin therapy over a 1-year period in elderly (≥65 years) compared with non-elderly (≤64 years) Japanese patients with uncontrolled diabetes [glycated hemoglobin (HbA1c) ≥ 8% for ≥ 3 months].

METHODS

This retrospective single-center cohort study was conducted in Japan. We screened all outpatients with diabetes mellitus who visited the clinic for diabetes treatment between December 2006 and March 2011. Of these patients, 132 with type 2 diabetes who were newly initiated on insulin therapy for continued poor glycemic control and undergoing comprehensive management through self-monitoring of blood glucose (SMBG) were registered to the study.

RESULTS

Thirty-two of 132 registered patients were excluded from the analysis. Among the 100 patients (67 non-elderly, 33 elderly) included in the analysis, median age and proportion of male patients was 69 years and 66.7%, respectively, among the elderly, and 52 years and 68.7%, respectively, among the non-elderly patients. After initiation of insulin therapy, median HbA1c levels improved from 9.6% to 7.2% in elderly patients, and from 10.8% to 7.3% in non-elderly patients at baseline and 12 months. Severe hypoglycemic events were not observed in either patient group; however, uncontrolled diabetes was ongoing in 31.8% of non-elderly and 15.4% of elderly patients, and obesity was associated with poor glycemic control.

CONCLUSION

Our results indicate that the effectiveness and safety of newly initiated insulin therapy are similar between elderly and non-elderly Japanese patients with uncontrolled diabetes, and highlight the importance of comprehensive management using SMBG to avoid hypoglycemia. Better glycemic control supported by adequate intensive management is required to improve mortality and morbidity.

Association between abdominal fat distribution and atherosclerotic changes in the carotid artery

AIM

We aimed to evaluate the association between abdominal fat distribution (e.g., abdominal visceral fat area [VFA], subcutaneous fat area [SFA], and total fat area [TFA]), waist circumference (WC), or body mass index (BMI) and atherosclerotic changes in the carotid artery after adjusting for common risk factors.

METHODS

The present study is a hospital-based, cross-sectional study. Study participants included 223 Japanese individuals who underwent a medical health checkup at Juntendo University Hospital, Tokyo, between December 2005 and August 2011. Multivariate logistic regression analysis was used to examine the association between abdominal VFA, SFA, TFA, the VFA/SFA ratio, WC, or BMI and intima-media thickness [IMT] (mean IMT≥1.1mm or maximum IMT≥1.2mm) as atherosclerotic changes in the carotid artery.

RESULTS

Multivariate logistic regression analysis showed that VFA (OR for ≥150cm(2) versus <100cm(2), 3.88; 95% CI, 1.39-10.85), BMI (OR for ≥27.6kg/m(2) versus <25kg/m(2), 5.22; 95% CI, 1.69-16.16), and TFA (OR for 200-285cm(2) versus <200cm(2), 4.15; 95% CI, 1.34-12.86: OR for ≥285cm(2) versus <200cm(2), 5.53; 95% CI, 1.76-17.35) were significantly associated with atherosclerotic changes in men. After adjustment for BMI, only TFA (OR for ≥285cm(2) versus <200cm(2), 3.76; 95%CI, 1.03-13.79) in men was significantly associated with atherosclerotic changes in the carotid artery.

CONCLUSIONS

Our results indicate that VFA, TFA, and BMI are independently associated with atherosclerotic changes in Japanese men. TFA may be considered as a valuable measure of atherosclerotic changes.

Influence of smoking on HIV infection among HIV-infected Japanese men

We performed a cross-sectional study that included 100 HIV-infected Japanese men without hemophilia to examine the influence of smoking on HIV infection. History of smoking was obtained using a questionnaire. The percentage of current smokers was 40 % and was the highest (50 %) among men in their forties. The mean Brinkman index (BI, number of cigarettes smoked per day multiplied by years of smoking) was 450. The percentage of patients with a BI ≥600 was significantly higher in patients with an AIDS-defining event than in those without an AIDS-defining event. A BI ≥600 was associated with an AIDS-defining event. Reducing smoking appears to be critical to enhancing disease management efforts in Japanese men with HIV.

Infective endocarditis with Lactococcus garvieae in Japan: a case report

Introduction

Lactococcus garvieae is a well-recognized fish pathogen, and it is considered a rare pathogen with low virulence in human infection. We describe the 11th case of L. garvieae infective endocarditis reported in the literature, and the first reported case in Japan.

Case presentation

We report a case of a 55-year-old Japanese woman who had native valve endocarditis with L. garvieae. The case was complicated by renal infarction, cerebral infarction, and mycotic aneurysms. After anti-microbial treatment, she was discharged from the hospital and is now well while being monitored in the out-patient clinic.

Conclusion

We encountered a case of L. garvieae endocarditis that occurred in a native valve of a healthy woman. The 16S ribosomal RNA gene sequencing was useful for the identification of this pathogen. Although infective endocarditis with L. garvieae is uncommon, it is possible to treat high virulence clinically.

Characterization of Foxp2-expressing cells in the developing spinal cord

Two members of winged-helix/forkhead transcription factors, Foxp1 and Foxp2, are expressed in the developing and adult CNS, including the striatum, cerebral cortex, and thalamus. In a previous study, we have demonstrated that Foxp1 is expressed in a subpopulation of V1 interneurons in addition to motor neurons of the spinal cord during mouse embryogenesis. However, the detailed expression pattern of Foxp2 and its relationship with Foxp1 in the developing spinal cord remains to be elucidated. To shed light on the potential roles of Foxp1 and Foxp2 in the developing spinal cord, we characterized Foxp2-expressing cells during mouse embryogenesis. At embryonic day (E) 11.0, Foxp2-expressing cells were first observed in the ventral spinal cord, which were Pax6(-), p27(+), and neuron-specific class III beta-tubulin(+) postmitotic neurons. Between E13.5 and E15.5, high expression of Foxp2 was observed in both medial and lateral parts of the ventral spinal cord. Double-immunofluorescence staining for Foxp2 with some homeodomain transcription factors revealed that Foxp2-expressing neurons were Pax2(+), En1(+), Evx1(-), Chx10(-), Gata3(-), and Lhx3(-) V1 interneurons in the intermediate zone throughout the ventral spinal cord, indicating that Foxp2-expressing neurons were also V1 interneurons with the same phenotypes as Foxp1-expressing interneurons. In addition, neither Foxp1 nor Foxp2 was expressed in ventral calbindin(+) Renshaw cells. However, Foxp2 did not colocalize with Foxp1 in interneurons of the ventral spinal cord. These findings suggest that Foxp1 and Foxp2 are expressed in the distinct subsets of V1 interneurons that belong to non-Renshaw cells in the ventral spinal cord during embryogenesis. Thus, Foxp1 and Foxp2 may be involved in the determination of the cell type identities during late embryogenesis: the classes of neurotransmitters and the functional subtypes of non-Renshaw cells, such as Ia and Ib inhibitory interneurons.

The Tokyo subway sarin attack--lessons learned

The sarin gas attack in the Tokyo subway system is reviewed from a clinical toxicology perspective. Based on the lessons learned from this attack, the following areas should be addressed on a global scale. First, an adequate supply of protective equipment is required, including level B protective equipment with a pressure demand breathing apparatus. In addition, a system should be established that enables a possible cause to be determined based on symptoms, physical findings, general laboratory tests, and a simple qualitative analysis for poisonous substances. If an antidote is needed, the system should enable it to be administered to the victims as quickly as possible. Preparation for a large-scale chemical attack by terrorists requires the prior establishment of a detailed decontamination plan that utilizes not only mass decontamination facilities but also public facilities in the area. A system should be established for summarizing, evaluating, and disseminating information on poisonous substances. Finally, a large-scale scientific investigation of the Tokyo sarin attack should be conducted to examine its long-term and subclinical effects and the effects of exposure to asymptomatic low levels of sarin.

Acute and chronic effects of sarin exposure from the Tokyo subway incident

The Tokyo subway sarin attack was the second documented incident of nerve gas poisoning in Japan. The St. Luke's International Hospital received 640 patients on the day of the attack. Reduction in plasma cholinesterase (ChE) activity was generally associated with the severity of acute signs of toxicity. With time and treatment, the value rose quickly. To evaluate possible residual signs of symptoms 1 year after the attack, we sent questionnaires to the victims; of 303 respondents, 45% still had some symptoms including eye problems, easy fatigability, headache, and fear. Therefore, we conducted a study in collaboration with investigators at the Tokyo University Department of Public Health to evaluate possible long-term neuropsychological sequelae. The findings suggest the need to closely follow such patients for possible persistent functional changes.

Expression of mKirre, a mammalian homolog of Drosophila kirre, in the developing and adult mouse brain

mKirre, a mammalian homolog of the Drosophila kirre, is expressed in bone marrow stromal cells and the brain. Although mKirre has been shown to support the hematopoietic stem cells, little is known about the function of mKirre in the brain. In the present study, to gain insights into the function of mKirre, we investigated the expression pattern of mKirre gene in the developing and adult mouse brain using in situ hybridization. In the adult brain, mKirre mRNA was highly expressed in the olfactory bulb, the piriform cortex, the cochlear nucleus, and the cerebellum. At embryonic day (E) 11.5, we could observe mKirre mRNA in the differentiating zones of various regions, such as the caudate-putamen, the geniculate body, the thalamus, the amygdala, and the brainstem. Its gene expression in these regions at E11.5 also persisted to the adult, in which its expression levels were much less prominent. After birth, we could first observe high expression of mKirre mRNA in the glomerular and mitral layers of the olfactory bulb, the cortical plate of the neocortex, the cochlear nucleus, and the molecular and granule cell layers of the cerebellum. In the hippocampus, its gene expression was first observed in the dentate gyrus at postnatal day 7. The spatiotemporal expression pattern of mKirre mRNA suggests important roles of mKirre in later developmental processes, especially the synapse formation.

Foxp1 gene expression in projection neurons of the mouse striatum

The developmental processes of maturation in the CNS are the result of specific events including mitogenesis, differentiation, and cell death which occur in a precise spatial and temporal manner. It has been reported that many transcription factors, including forkhead transcription factors, play a key role in these processes. First, we examined the expression pattern of the forkhead transcription factor Foxp1 in the adult CNS. Foxp1 was highly expressed in the striatum and moderately in the cerebral cortex, CA1/2 subfields of the hippocampus, and several thalamic nuclei. In situ hybridization combined with immunohistochemistry in the striatum of adult mice revealed that Foxp1 mRNA was detected in a subset of projection neurons, not in interneurons. In addition, the expression of Foxp1 mRNA was observed in the developing basal ganglia with the exception of the globus pallidus. Thus, Foxp1 mRNA was expressed in a subset of striatal projection neurons, probably the matrix neurons. The expression pattern of Foxp1 mRNA suggests that Foxp1 may play a role in the development and formation of a circuit in the basal ganglia, which is involving the matrix neurons.

[Laboratory medicine in the field of emergency medicine and disaster medicine--Old-And-New tools of emergency medical service]

We reviewed the characteristics of the field of laboratory medicine concerning emergency medicine and disaster medicine. Gram's stain was apt to be made light of by clinicians, but it has been reviewed again. A modern sophisticated analysis system is expected for the consequence management of NBC terrorism and mass poisoning, but we would like to emphasize the importance of the basic physical strength of laboratory medicine, such as Gram's stain, to the meaning of old-and-new technology.

Enhancement of Rho/Rho-kinase system in regulation of vascular smooth muscle contraction in tachycardia-induced heart failure

OBJECTIVE

The Rho/Rho-kinase system regulates Ca(2+) sensitivity in vascular smooth muscle. A new drug, Y-27632, specifically inhibits Rho-kinase and hence decreases the phosphorylation of myosin light chain, thus reducing contraction. Here, we compare the effects of Y-27632 and nifedipine on the vasoconstrictor response of the femoral artery in heart failure.

METHODS

Heart failure (HF) was produced by chronic rapid RV pacing (250 bpm, 28 days, six dogs). Indo1-AM was loaded into endothelium-denuded femoral artery segments for measuring intracellular [Ca(2+)]. Tension and changes in intracellular [Ca(2+)] [the change in the ratio (418 nm/468 nm) of Indo1 fluorescence (F(ratio))] were simultaneously measured in Krebs-Ringer solution.

RESULTS

In HF: (i) norepinephrine (10 microM) produced greater tension (784+/-52 g/cm(2)) than in control (502+/-64 g/cm(2)) despite a similar increase in F(ratio), indicating increased Ca(2+) sensitivity in vascular smooth muscle; (ii) nifedipine attenuated this enhanced response by only a maximum of 27% at 1 micromol/l with a 56% reduction in F(ratio); (iii) Y-27632 attenuated it by a maximum of 80% at 100 micromol/l without a significant change in F(ratio); (iv) RhoA protein and mRNA expression levels in the femoral artery were up-regulated by +110% and +56%, respectively, while those of Rho-kinase were unchanged.

CONCLUSIONS

The Ca(2+)-sensitizing mechanism involving the Rho/Rho-kinase system may be deeply involved in the enhanced arterial vasoconstriction seen in HF. Since Y-27632 attenuated this response in small arteries, it shows potential as a novel, potent vasodilator for the treatment of HF.

Altered interaction of FKBP12.6 with ryanodine receptor as a cause of abnormal Ca(2+) release in heart failure

OBJECTIVE

Little information is available as to the Ca(2+) release function of the sarcoplasmic reticulum (SR) in heart failure. We assessed whether the alteration in this function in heart failure is related to a change in the role of FK binding protein (FKBP), which is tightly coupled with the cardiac ryanodine receptor (RyR) and recently identified as a modulatory protein acting to stabilize the gating function of RyR.

METHODS

SR vesicles were isolated from dog LV muscles [normal (N), n=6; heart failure induced by 3-weeks pacing (HF), n=6]. The time course of the SR Ca(2+) release was continuously monitored using a stopped-flow apparatus, and [3H]ryanodine-binding and [3H]dihydro-FK506-binding assays were also performed.

RESULTS

FK506, which specifically binds to FKBP12.6 and dissociates it from RyR, decreased the polylysine-induced enhancement of [3H]ryanodine-binding by 38% in N (P<0.05) but it had no effect in HF. In HF, the rate constant for the polylysine-induced Ca(2+) release from the SR was 61% smaller than in N. FK506 decreased the rate constant for the polylysine-induced Ca(2+) release by 67% in N (P<0.05) but had no effect in HF. The [3H]dihydro-FK506-binding assay revealed that the number (B(max)) of FKBPs was decreased by 83% in HF (P<0.05), while the K(d) value was unchanged. FK506 did not significantly change SR Ca(2+.)-ATPase activity in either N or HF.

CONCLUSIONS

In HF, the number of FKBPs showed a tremendous decrease; this may underlie the RyR-channel instability and the impairment of the Ca(2+) release function of RyR seen in the failing heart.

Altered stoichiometry of FKBP12.6 versus ryanodine receptor as a cause of abnormal Ca(2+) leak through ryanodine receptor in heart failure

BACKGROUND

In the pathogenesis of cardiac dysfunction in heart failure, a decrease in the activity of the sarcoplasmic reticulum (SR) Ca(2+)-ATPase is believed to be a major determinant. Here, we report a novel mechanism of cardiac dysfunction revealed by assessing the functional interaction of FK506-binding protein (FKBP12.6) with the cardiac ryanodine receptor (RyR) in a canine model of pacing-induced heart failure.

METHODS AND RESULTS

SR vesicles were isolated from left ventricular muscles (normal and heart failure). The stoichiometry of FKBP12.6 per RyR was significantly decreased in failing SR, as assessed by the ratio of the B(max) values for [(3)H]dihydro-FK506 to those for [(3)H]ryanodine binding. In normal SR, the molar ratio was 3.6 ( approximately 1 FKBP12.6 for each RyR monomer), whereas it was 1.6 in failing SR. In normal SR, FK506 caused a dose-dependent Ca(2+) leak that showed a close parallelism with the conformational change in RyR. In failing SR, a prominent Ca(2+) leak was observed even in the absence of FK506, and FK506 produced little or no further increase in Ca(2+) leak and only a slight conformational change in RyR. The level of protein expression of FKBP12.6 was indeed found to be significantly decreased in failing SR.

CONCLUSIONS

An abnormal Ca(2+) leak through the RyR is present in heart failure, and this leak is presumably caused by a partial loss of RyR-bound FKBP12.6 and the resultant conformational change in RyR. This abnormal Ca(2+) leak might possibly cause Ca(2+) overload and consequent diastolic dysfunction, as well as systolic dysfunction.

Effect of milrinone on left ventricular relaxation and Ca(2+) uptake function of cardiac sarcoplasmic reticulum

Milrinone, a phosphodiesterase 3 (PDE3) inhibitor, is known to enhance left ventricular (LV) contractility by an inhibition of the breakdown of cAMP through the mechanism inhibiting PDE3. However, it is unclear whether milrinone also exerts positive lusitropy, like dobutamine. Here, we assessed the effects of milrinone on in vivo LV relaxation, as well as the Ca(2+)-ATPase activity and the Ca(2+) uptake function of the cardiac sarcoplasmic reticulum (SR), compared with the effect of dobutamine on those functions. After dobutamine (3 microg x kg(-1) x min(-1)) was administered, the peak value of the first derivative of LV pressure (+dP/dt) increased by 46%, whereas the time constant (tau) of LV pressure decay decreased by 6.9%, respectively. After milrinone (10 microg/kg) was administered, the peak +dP/dt increased to a similar extent as dobutamine (46%), whereas tau decreased much more than dobutamine (19.9%; P < 0.05). In LV crude homogenate, the thapsigargin-sensitive, Ca(2+)-ATPase activity-cAMP relationships was significantly less increased by milrinone compared with dobutamine (P < 0.05), indicating the higher sensitivity of the SR Ca(2+)-ATPase activity on cAMP by milrinone than by dobutamine. In the SR vesicles purified from LV muscles, the addition of cAMP increased the SR Ca(2+) uptake in a dose-dependent fashion, and the PDE3 inhibitors (milrinone and cGMP) significantly augmented this response (P < 0.05). Hence, milrinone substantially improved LV relaxation in association with an acceleration of the SR Ca(2+)-ATPase activity and the SR Ca(2+) uptake. This acceleration might be due to an inhibition of the membrane-bound PDE3 in the SR, leading to a local elevation of cAMP.

Mechanism of preserved positive lusitropy by cAMP-dependent drugs in heart failure

In tachycardia-induced heart failure (HF), positive lusitropic effects of milrinone or dobutamine were assessed by evaluating the time constant of left ventricular (LV) pressure decay (tau) and Ca(2+)-ATPase activity of the sarcoplasmic reticulum (SR). The peak value of the positive first derivative of LV pressure (+dP/dt) was less increased, either by dobutamine (2-10 microg x kg(-1) x min(-1)) or by milrinone (4-20 microg/kg), in HF than in control (P < 0.05), whereas tau was shortened to an extent similar to that in control with dobutamine [P = not significant (NS)] and to an even greater extent with milrinone (P < 0.05). Ca(2+)-ATPase activity increased similarly in HF and control with dobutamine (1 microM; +11% in HF vs. +12% in control, P = NS), whereas it increased more with milrinone (1 microM; +19% in HF vs. +11% in control, P < 0.05). Ca(2+)-ATPase activity-cAMP relationships were shifted to the left by milrinone or dobutamine in HF compared with control. Thus, in HF, the sensitivity of Ca(2+)-ATPase activity to cAMP was increased on addition of cAMP-dependent inotropic agents, contributing to the preservation of positive lusitropy.

Abnormal Ca2+ release from cardiac sarcoplasmic reticulum in tachycardia-induced heart failure

OBJECTIVE

In heart failure, little information is available as to the Ca2+ release function of sarcoplasmic reticulum (SR), which plays a major role in cardiac contractile function. Here, we assessed the rapid kinetics of drug-induced Ca2+ release from cardiac SR in combination with a measurement of ryanodine binding in heart failure.

METHODS

The SR vesicles were isolated from dog left ventricular (LV) muscles (normal (N), n = 10; pacing induced heart failure (HF), n = 10). The time course of SR Ca2+ release was continuously monitored by a stopped-flow apparatus using arsenazoIII as a Ca2+ indicator, and Ca2+ uptake and [3H]ryanodine binding assays were done using a filtration method.

RESULTS

The amount of Ca2+ uptake was reduced in HF to 55% of N (P < 0.05). Even the more marked and earlier appeared decrease was seen in the rate constant and the initial rate of polylysine (PL; a specific release trigger)-induced Ca2+ release (P < 0.05). However, the PL concentration dependency of the initial rate shifted towards lower concentrations of PL in HF than in N ([PL] at half maximum stimulation = 0.13 vs. 0.35 microM). The [3H]ryanodine binding assay revealed a lower Bmax (pmol/mg) in HF than in N (0.91 +/- 0.19 vs. 2.64 +/- 0.59, P < 0.05), but no difference in Kd (nM) (0.95 +/- 0.29 vs. 0.90 +/- 0.11, P = n.s.). The [PL] dependency on the enhancement of [3H]ryanodine binding again showed a shift towards lower [PL] in HF than in N.

CONCLUSIONS

In pacing-induced heart failure, the Ca2+ releasing function of SR is disturbed, which may result in an intra-cellular Ca2+ transient that was slowed down.

Effects of balanced vasodilator, flosequinan, on aortic impedance in failing heart

An arteriovenous vasodilator, flosequinan, has been shown to be effective for the treatment of acute heart failure. However, little is known as to its effect on aortic impedance, which is known to be a proper and precise expression of left ventricular (LV) afterload. To evaluate the acute cardiovascular effect of flosequinan in failing heart, we administered flosequinan intravenously to seven dogs with cardiac failure produced by an infusion of carbon powder (20-50 microm in diameter) into left main trunks of coronary artery. The LV-pump function was severely impaired after intracoronary injection of carbon powder, as evidenced by the findings that cardiac output, circumferential shortening velocity (mean Vcf), and peak +dP/dt of LV pressure were all decreased, associated with a significant increase in LV end-diastolic pressure. Flosequinan (0.9 mg/kg, i.v.) increased cardiac output by 28%, mean Vcf by 44%, and peak +dP/dt by 24%, whereas it decreased total systemic resistance by 32%, time constant of LV pressure decay by 22%, and LV end-diastolic pressure by 18%. Moreover, flosequinan substantially decreased the pulsatile components of LV afterload (i.e., characteristic impedance by 11% and arterial wave reflection coefficient by 45%). Thus flosequinan exerted not only positive inotropic but also positive lusitropic effects, in association with a significant reduction of both pulsatile and steady components of LV afterload, contributing to an improvement of LV-pump function in acute cardiac failure.

Polylysine-induced rapid Ca2+ release from cardiac sarcoplasmic reticulum

The rapid kinetics of polylysine-induced Ca2+ release from cardiac sarcoplasmic reticulum (SR) was assessed in combination with its effect on ryanodine binding. SR vesicles were isolated from canine cardiac SR. The time course of SR Ca2+ release was continuously monitored by a stopped-flow apparatus, and [3H]ryanodine binding was done by using the filtration method. The initial rate of polylysine-induced Ca2+ release from cardiac SR revealed different concentration dependence from those observed in skeletal SR. The initial rate peaked at 0.11 microM, followed by a decrease at higher concentrations in skeletal SR, whereas it increased to 3.7 microM in cardiac SR. The [3H]ryanodine binding was also stimulated by polylysine with an identical parallelism with Ca2+ release in terms of polylysine concentration dependence. Thus we demonstrated that the cardiac SR Ca2+ release channel is sensitive to activation by polylysine and that there is a difference in the concentration dependence of polylysine-induced activation of cardiac and skeletal SR Ca2+ release channels.

TSH receptor antibody-associated thyroid dysfunction following subacute thyroiditis

OBJECTIVE

Autoimmunity plays an important role in the development of thyrotrophin (TSH) receptor antibodies and the pathogenesis of Graves' disease and Hashimoto's thyroiditis. On the other hand, subacute thyroiditis is a self-limited inflammatory disease of presumed viral aetiology. The aim of this study was to examine whether subacute thyroiditis triggers TSH receptor antibody-associated thyroid disorders.

PATIENTS

We reviewed 1,697 patients with subacute thyroiditis seen between 1985 and 1995.

DESIGN AND MEASUREMENTS

We measured antibodies which inhibit the TSH binding to the TSH receptor (TBIAb), thyroid stimulating antibodies (TSAb) and antibodies that block TSH action (TBAb). Other thyroid autoantibodies were also determined.

RESULTS

TBIAb became positive in 38 patients following subacute thyroiditis. Thyroid function after the development of TBIAb appeared to be influenced by the bioactivity of the antibody. Hyperthyroidism developed in the presence of TSAb, and so did hypothyroidism in the presence of TBAb, although 21 patients did not have thyroid dysfunction despite high titres of TBIAb. Fifteen out of 17 patients recovered from hyperthyroidism or hypothyroidism after the disappearance of TBIAb sometimes even without medication. TBIAb-positive patients had a high incidence of a family history of thyroid disease and positive anti-thyroid microsomal antibodies. An ophthalmopathy similar to Graves' disease was also observed in 3 patients.

CONCLUSIONS

Subacute thyroiditis may trigger autoreactive B cells to produce TSH receptor antibodies, resulting in TSH receptor antibody-associated thyroid dysfunction in some patients.

Propolypeptide of von Willebrand factor is a novel ligand for very late antigen-4 integrin

We have previously reported that propolypeptide of von Willebrand factor (pp-vWF) promotes melanoma cell adhesion in a beta1 integrin-dependent manner. In this report, we identified the alpha subunit of the cell adhesion receptor for pp-vWF as alpha4. Human leukemia cell lines that express alpha4beta1 integrin (very late antigen-4, VLA-4), but not cell lines which lack VLA-4, attached well to pp-vWF substrate and these adhesions were completely inhibited by anti-alpha4 integrin monoclonal antibody HP2/1. Adhesion of mouse melanoma expressing alpha4 integrin was also inhibited by anti-mouse alpha4 mAb PS/2. Furthermore, transfection of human alpha4 cDNA into alpha4(-) Chinese hamster ovary cells resulted in an acquisition of adhesive activity to pp-vWF, indicating that pp-vWF is a ligand for VLA-4 integrin. Using a recombinant fragment of pp-vWF, the cell attachment site was shown to be located within amino acid residues 376-455 of pp-vWF. A series of synthetic peptides covering this region were tested for the ability to promote cell attachment and a 15-residue peptide designated T2-15 (DCQDHSFSIVIETVQ, residues numbered 395-409) promoted VLA-4 dependent cell adhesion. The peptide was also capable of inhibiting cell adhesion to pp-vWF, suggesting that this sequence represents the cell attachment site. By affinity chromatography using peptide T2-15-Sepharose, it was found that alpha4beta1 integrin complex from extracts of surface iodinated B16 cells specifically bound to the peptide. These results strongly suggest that pp-vWF is a novel physiological ligand for VLA-4.

Clinical and electrophysiological characteristics of atrial standstill

To clarify the clinical and electrophysiological characteristics of atrial standstill (AS) we studied 11 patients (7 males and 4 females), whose average age was 62 years and who were followed over a period of 4-179 months. Underlying heart disease was present in nine patients and two cases were idiopathic. Major clinical symptoms in the 11 cases included Adams-Stokes attacks, and dyspnea on exertion. In the standard 12-lead ECGs obtained on admission, the P wave was absent in six cases. Atrial flutter (AF) was noted in 3, atrial fibrillation (Af) in 1, and multifocal atrial tachycardia in 1. In some cases, the ECG initially showed AF or Af, and was transformed after several years into ectopic atrial tachycardia or an ectopic atrial rhythm with a markedly decreased amplitude of the P wave. Finally, the P wave disappeared over a prolonged period. When intracardiac mapping was performed, the atrial electrograms tended to diminish at the site of high, mid-lateral right atrium (RA). Electrograms were remained present in the vicinity of the tricuspid valve (TV) annulus. A repeated mapping and pacing study conducted in two patients revealed that the "silent" area spread toward the lower site of RA. During the average follow-up period of 64 months, four patients died. The interval until death in one patient with myocarditis was 6 months, and in another with dilated cardiomyopathy (DCM) it was 8 months. It appears that the atrial muscular lesion starts in the high lateral RA and progresses toward the lower RA, then to the vicinity of the TV annulus. A diffuse and progressive disturbance may occur not only in the atrial muscle, but also in the atrioventricular conduction system in patients with AS who had progressive myocarditis or DCM.

Pulmonary hypertension and antiphospholipid antibody in a patient with Sjögren's syndrome

A 57-year-old female patient with Sjögren's syndrome was complicated with pulmonary hypertension (PH) and antiphospholipid antibody (aPL). She had a history of fetal losses, deep vein thrombosis and chronic thyroiditis. On admission, severe pulmonary hypertension, thrombocytopenia, lupus anticoagulant and a decreased level of protein C were found. Pulmonary artery perfusion scintigram revealed multiple defects. She died suddenly despite an intensive therapy. Intimal proliferation with angiomatoid lesions in small pulmonary arteries was observed by autopsy. Since a close relationship between PH and aPL in connective tissue disease is found, it is important to carefully analyze the antiphospholipid antibodies in patients with PH.

A case of arrhythmogenic right ventricular dysplasia with atrial flutter

A 57-year-old male who had arrhythmogenic right ventricular dysplasia (ARVD) with recurrent atrial flutter (AF) is reported. The patient had more frequent episodes of AF than of ventricular arrhythmias. Magnetic resonance imaging, echocardiography and right ventriculography revealed dilatation of the right ventricle and endomyocardial biopsy specimens from the right ventricle showed findings which were compatible with ARVD. The left ventricular specimen, however, also revealed a loss of myocytes and interstitial fibroelastic changes. The present case demonstrates an overlap of post-inflammatory or primary endomyocardial fibroelastic changes with ARVD.

[Studies on patients with a discrepancy between free thyroid hormones and thyrotropin values]

Thyroid function has been almost exactly evaluated by the measurement of serum free thyroxine (FT4), free triiodothyronine (FT3) and thyrotropin (TSH) concentrations. However, we occasionally experience patients who show a discrepancy between free thyroid hormones and TSH values, and the assessment of thyroid function in such cases is extremely difficult. Thyroid hormone autoantibodies (THAA) interfere with radioimmunoassay (RIA) of FT4 and FT3 by giving inappropriate values. To investigate the incidence of THAA, immune precipitation of patients' sera after incubation with labelled T4 (125I-T4) or T3 (125I-T3) analog tracer was done in 394 patients with thyroid diseases. 9 patients (2.3%) showed an increased binding of 125I-T4 or 125I-T3 analog. Heterophilic antimouse antibodies in a patient's serum (human antimouse immunoglobulin antibodies: HAMA) can interfere in two-site immunometric assays (IMA) using mouse monoclonal antibodies and result in spuriously increased serum TSH concentrations. Manufacturers now customarily add nonspecific mouse immunoglobulins into their assay kits to absorb HAMA and prevent such interference. This approach may not always be enough to prevent HAMA interference in all samples. In 14 thyrotoxic patients with inappropriately high TSH measured by an IMA kit, we measured the levels of TSH by the further addition of mouse serum into this kit. Their serum TSH levels were fully suppressed except for 2 patients with a syndrome of inappropriate secretion of TSH (SITSH). The presence of abnormal albumin in the serum also interferes with RIA of FT4 and FT3. We experienced a female case of Graves' disease treated with methimazole who showed an inappropriately high serum FT3 measured by an analog tracer RIA kit, whose serum FT4, FT3 and TSH were 1.31 ng/dl, 19.3 pg/ml and 1.9 mu U/ml respectively. Although the anti-T3 autoantibody was considered to be present initially, immune precipitation of her serum with 125I-T3 analog tracer gave a negative result. In order to elucidate this finding, Sephadex-G200 chromatography of her serum after incubation with 125I-T3 analog tracer was done. Radioactivity of her serum in albumin fraction was significantly higher than that of normal control serum to indicate the presence of abnormal albumin in the serum. In conclusion, to assess the thyroid function of a patient with a discrepancy between free thyroid hormones and TSH values, it is important to consider the presence of THAA, HAMA, or rarely, an abnormal albumin.

Intra-His bundle block corresponds with interruption of the branching portion of the His bundle

We compared His-bundle electrograms with pathological findings of the atrioventricular conduction system in four patients with complete atrioventricular intra-His block with narrow QRS complexes on ECG. Split His electrograms were recorded at the time of electrophysiological study. The patients died from noncardiac causes at 10 days, 1 year, 4 years, and 9 years, respectively, after the pacemaker implantation. Serial sections through the atrioventricular conduction system revealed strictly localized more than 50% reduction of conducting cells replaced by fibrosis at the branching portion of His bundle. The proximal portions of the bundle branches also exhibited decrease of the conducting cells showing a rough positive relation with the patient's age. Therefore, we considered that the H1 spikes seen on His-bundle electrograms originated from the penetrating portion of His, which was virtually intact in our cases, and that the H2 spikes originated from the right side of the distal branching portion of His.

[Cases of Graves' disease with falsely high TSH values due to interfering substances which cross-link with mouse monoclonal antibodies in the TSH assay kits]

It has been reported that highly sensitive two-site immunometric assays occasionally indicate falsely high serum TSH values. A possible reason for this is that heterophilic antibodies interfere with these assays. Recently we had a patient in whom the Delfia TSH kit falsely indicated an elevated serum TSH value. A 29-year-old female was diagnosed as having Graves' disease and was referred to Ito Hospital for surgical treatment. Her thyroid hormone values were distinctly high two months before admission (FT3: 20.7pmol/L, FT4: 42.3pmol/L), but her serum TSH level was normal (1.1mU/l). She was clinically hyperthyroid, and T3 and T4 values determined after ethanol extraction and T3 or T4 analog binding rates did not indicate the presence of T3 or T4 antibodies. Her TSH value became undetectable when mouse IgG was added to the assay. These results suggested that the "normal" serum TSH value was caused by interfering substances such as anti-mouse IgG antibodies which had cross-linked with mouse monoclonal antibodies in the Delfia TSH kit. Another 12 patients who were suspected of having the interfering substances were examined because of the discordance between TSH values and thyroid hormone values. All of the serum TSH values measured using the DELFIA TSH kit decreased when mouse IgG was added. In another case, the presence of serum TSH could not be detected using the Delfia TSH kit but could be measured using the RIABEAD II TSH kit.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of subacute thyroiditis with highly positive thyrotropin receptor antibodies and normal radioiodine uptake]

In this paper, we report on a 40-year-old female with subacute thyroiditis (SAT) who showed high levels of TSH-binding inhibitory immunoglobulins (TBII) and thyroid-stimulation blocking antibodies (TSBAb) from the early stage of the disease. Thyrotoxicosis continued for 2 months and it was subsequently followed by severe hypothyroidism. Levothyroxine was then started. At that time, both TBII and TSBAb were still positive, but they disappeared 6 months later and she remained euthyroid thereafter without treatment. When she was in a thyrotoxic phase and had a suppressed TSH level, her 24-hour radioiodine uptake was not suppressed (11%), and thyroid scan showed partial suppression of uptake in the right lobe. These observations indicate that the presence of TSH receptor antibodies (TRAb) may have modified the changes in thyroid state and the course of SAT.

A case of idiopathic ventricular fibrillation with incomplete right bundle branch block and persistent ST segment elevation

We report the case of a 42-year-old male who suffered from ventricular fibrillation (VF) without obvious QT prolongation. His electrocardiogram showed incomplete right bundle branch block (IRBBB) and persistent ST segment elevation in the right precordial leads during sinus rhythm. Cardiac catheterization revealed no overt heart disease except moderate endocardial and subendocardial fibrosis in the left ventricle. Mental stress seemed to trigger VF, and ST elevation became prominent just before VF. Propranolol and mexiletine have been effective in preventing VF for over 3 years.

[Change in serum G-CSF levels in patients with Graves' disease by treatment with methimazole]

We evaluated the determination of serum G-CSF in the diagnosis of granulocytopenia due to methimazole (MMI) in 54 patients with Graves' disease, while they were being treated with MMI, by way of measuring WBC counts and serum levels of G-CSF, thyroid hormones, IgE, and interleukin-2. Serum TSH was measured by immunoradiometric assay, serum G-CSF was done by enzyme immunoassay, thyroid hormones and IgE were done by radioimmunoassay, and serum Interleukin-2 was done by enzyme-linked immunosorbent assay. The population whose G-CSF levels were higher than the minimum detectable level (30pg/ml) was 6 (30%) in normal subjects, 4 (22%) in patients with untreated Graves' disease, 2 (12%) in patients with treated euthyroid Graves' disease, 3 (23%) in patients with Graves' disease who had gone through agranulocytosis, and 2 (33%) in patients with Graves' disease complicated with granulocytopenia. There was no significant change in WBC counts for 4 weeks, but there was a significant difference between WBC counts before treatment and those at 8 weeks after treatment. We observed no significant change of serum G-CSF levels in patients with Graves' disease under treatment. However, there were significantly high levels of serum G-CSF and significantly low counts of WBC in patients with Graves' disease complicated with granulocytopenia induced by MMI, compared with those in normal subjects, patients with untreated Graves' disease, patients with treated euthyroid Graves' disease, and patients with euthyroid Graves' disease who had gone through agranulocytosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term follow-up study of three patients with the long QT syndrome

We studied three women with the long QT syndrome. They were aged 42, 52 and 25 years and had experienced recurrent syncopal attacks. We followed case 1 for 17, case 2 for 18, and case 3 for over 6 y. The attacks tended to occur during the premenstrual stage in case 1 and case 2; case 3 often experienced attacks after exercise. The QT(U)c intervals on admission were 0.68, 0.62, and 0.50 in case 1, 2, and 3, respectively. Torsade de pointes followed by ventricular fibrillation was documented in case 1 and case 2. Although each was treated with a beta-blocker, none was fully compliant with the regimen. In case 1, estrogen therapy administered to maintain the hormonal balance premenstrually effectively prevented attacks. Despite the inconsistent use of beta-blockers, the attacks in case 1 and case 2 tended to decrease with age. Case 2 experienced no attacks after menopause. Cause 3 took medication consistently and remained free of attacks for over 6 y. Although she discontinued beta-blocker therapy because of pregnancy, she has experienced no attacks to date. These case studies suggest that hormonal status may be important in the development of syncopal attacks in female patients with the long QT syndrome.