Biomedical subjects

Hiroshi Satoh

Publications and source records attributed to Hiroshi Satoh.

At least 19 recordsLinked to original sources

PubMed2007

Detection of carotid atherosclerosis in individuals with masked hypertension and white-coat hypertension by self-measured blood pressure at home: the Ohasama study.

OBJECTIVE: To investigate carotid atherosclerosis in individuals with masked hypertension (MHT) and white-coat hypertension (WCHT) in a general population. METHODS: Self-measurement of blood pressure at home (HBP) and casual blood pressure (CBP) measurements were recorded in 812 individuals aged at least 55 years (mean 66.4 years) from the general Japanese population. The intima-media thickness (IMT) of the near and far wall of both common carotid arteries was measured and averaged. The relationships between carotid atherosclerosis (IMT and plaque) and the four blood pressure groups (sustained normal blood pressure: HBP < 135/85 mmHg, CBP < 140/90 mmHg; WCHT: HBP < 135/85 mmHg, CBP >or= 140/90 mmHg; MHT: HBP >or= 135/85 mmHg, CBP < 140/90 mmHg; sustained hypertension: HBP >or= 135/85 mmHg, CBP >or= 140/90 mmHg) were examined using multivariate analysis adjusted for possible confounding factors. RESULTS: Adjusted IMT in individuals with sustained hypertension [0.77 mm; 95% confidence interval (CI) 0.75 to 0.79 mm] and MHT (0.77 mm; 95% CI 0.73 to 0.80 mm) was significantly greater than in those with sustained normal blood pressure (0.71 mm; 95% CI 0.69 to 0.72 mm) and WCHT (0.72 mm; 95% CI 0.71 to 0.74 mm) (P < 0.0001). The odds ratios for the presence of plaques in all four groups were similar to the trends in IMT. CONCLUSIONS: Our findings imply that CBP measurements alone are insufficient to distinguish individuals at high risk of carotid atherosclerosis from those at low risk. However, these individuals do have distinct HBP measurements, suggesting that HBP measurement could become a valuable tool for predicting carotid atherosclerosis.

Aged↗

PubMed2006

Predicting stroke using 4 ambulatory blood pressure monitoring-derived blood pressure indices: the Ohasama Study.

We investigated the association between stroke and blood pressure (BP) indices (systolic BP [SBP], diastolic BP [DBP], mean BP [MBP], and pulse pressure [PP]) determined by ambulatory BP monitoring. The predictive power for stroke of these indices was compared in the general Japanese population. We obtained ambulatory BP data in 1271 subjects (40% men) aged > or = 40 (mean: 61) years. During a mean follow-up of 11 years, 113 strokes were observed. The multivariate adjusted relative hazard and likelihood ratio for a 1-SD increase for each BP index was determined by Cox proportional hazard regression. Comparison of the likelihood ratio between Cox models including 2 indices and those including 1 index indicated that PP was significantly less informative than other indices (P<0.01 when adding MBP, SBP, or DBP to the PP model; P>0.09 when adding PP to the model including another index). However, after removing age from covariates, PP became more informative than DBP and MBP (P<0.0001 when adding PP to the MBP or DBP model, whereas SBP was more informative than PP even after removing age; P<0.05 when adding SBP to the PP model). In conclusion, PP was the weakest predictor of stroke. Exclusion of age from covariates increased the predictive power of PP, suggesting that the stroke risk associated with PP reflected the risk of aging per se.

Adult↗

PubMed2006

Prediction of stroke by home "morning" versus "evening" blood pressure values: the Ohasama study.

Predictive power of self-measured blood pressure at home (home BP) for cardiovascular disease risk has been reported to be higher than casual-screening BP. However, the differential prognostic significance of home BP in the morning (morning BP) and in the evening (evening BP), respectively, has not been elucidated. In the Ohasama study, 1766 subjects (>or=40 years) were followed up for an average of 11 years. The predictive power for stroke incidence of evening BP was compared with that of morning BP as continuous variables. The Cox regression model demonstrated that evening BP and morning BP predicted future stroke risk equally. Subjects were also assigned to 1 of 4 categories based on home BP. In this analysis, stroke risk in morning hypertension ([HT] morning BP >or=135/85 mm Hg and evening BP <135/85 mm Hg; relative hazard (RH): 2.66; 95% CI:1.64 to 4.33) and that in sustained HT(morning BP and evening BP >or=135/85 mm Hg; RH: 2.38; 95% CI: 1.65 to 3.45) was significantly higher than that in normotension (morning BP and evening BP <135/85 mm Hg). The risk in morning HT was more remarkable in subjects taking antihypertensive medication (RH: 3.55; 95% CI: 1.70 to 7.38). Although the risk in evening HT (morning BP <135/85 mm Hg and evening BP >or=135/85 mm Hg) was higher than that in normotension, the differences were not significant. In conclusion, morning BP and evening BP provide equally useful information for stroke risk, whereas morning HT, which indicates HT specifically observed in the morning, might be a good predictor of stroke, particularly among individuals using anti-HT medication.

Aged↗

PubMed2006

Fish consumption and time to pregnancy in Japanese women.

The work described in this paper examined the possible relationship between fish consumption and human fecundity among Japanese women using hair mercury level and time to pregnancy (TTP) as indicators of fish consumption and fecundity. We hypothesized that hair mercury concentrations reflect the level of fish consumption and, consequently, can also be taken to indicate the level of intake of organochlorine compounds (OCs) such as dioxins and polychlorinated biphenyls (PCBs) for which fish are the primary source, and which can disrupt normal human reproductive processes. TTP was obtained by a self-administered questionnaire from women who had been delivered of a baby at either of two hospitals in Sendai, Japan, during the period of January 2002-March 2004. Total mercury concentration in their hair (0-3cm from the scalp) was determined by cold vapor atomic absorption spectrometry. Of the 298 women approached, 193 (65%) reported their TTP. The subjects were classified into two groups according to their TTP: group 1, 0-12 months TTP; and Group 2, >12 months TTP. A step-down procedure backward binominal logistic regression analysis was performed by using age, BMI, parity, frequency of intercourse, life-style parameters (smoking, drinking and dietary habits) and hair mercury level of the female subjects and their partners as independent variables. Two separate analyses were performed by including/excluding information on the partners of the subjects. The analyses did not extract hair mercury concentration as significant indicating that fish consumption did not prolong TTP, which was not consistent with the results of our previous study, i.e., in that study frequent fish eaters showed prolonged TTP. Possible reasons of the negative result are discussed and it is suggested that the hair mercury levels in the present study were not an appropriate indicator of fish consumption of the subjects or of their exposure to OCs. Further study on the relationship between fish consumption (and, ultimately, of OCs intake) and fecundity with more appropriate indicators of fish consumption and/or fish-mediated pollutants intake are warranted to characterize the health risk posed by fish consumption.

Adult↗

PubMed2006

Correlations between mercury concentrations in umbilical cord tissue and other biomarkers of fetal exposure to methylmercury in the Japanese population.

Methylmercury (MeHg) is one of the most risky substances to affect humans through fish consumption, and the fetus is known to be in the most susceptible group. Our objective in this study is to examine the relationships of total mercury (THg) and MeHg concentrations between umbilical cord tissue and other tissues as biomarkers of fetal exposure to MeHg in the Japanese population. In total, 116 paired samples were collected in three Japanese districts, the Tsushima Islands, Fukuoka City, and Katsushika ward of metropolitan Tokyo. THg was measured for hair and THg and MeHg were measured in cord tissues, maternal blood, and cord blood. The relationships among tissues in Hg concentrations were similar among districts. Therefore, we analyzed the relationships using all the samples. More than 90% of Hg in cord tissue, cord blood, and maternal blood was MeHg. THg and MeHg in cord blood was about two times higher than in maternal blood. A strong correlation was found between THg and MeHg in cord tissue. The cord tissue THg and MeHg showed a strong correlation with cord blood Hg, which is recognized as the best biomarker for fetal exposure to MeHg. The findings of this study indicate the significance of cord tissue THg and MeHg as biomarkers for fetal exposure to MeHg at parturition.

Adult↗

PubMed2006

Evaluation of right and left ventricular function by quantitative blood-pool SPECT (QBS): comparison with conventional methods and quantitative gated SPECT (QGS).

Though quantitative ECG-gated blood-pool SPECT (QBS) has become a popular tool in research settings, more verification is necessary for its utilization in clinical medicine. To evaluate the reliability of the measurements of left and right ventricular functions with QBS, we performed QBS, as well as first-pass pool (FPP) and ECG-gated blood-pool (GBP) studies on planar images in 41 patients and 8 healthy volunteers. Quantitative ECG-gated myocardial perfusion SPECT (QGS) was also performed in 30 of 49 subjects. First, we assessed the reproducibility of the measurements of left and right ventricular ejection fraction (LVEF, RVEF) and left and right ventricular end-diastolic volume (LVEDV, RVEDV) with QBS. Second, LVEF and RVEF obtained from QBS were compared with those from FPP and GBP, respectively. Third, LVEF and LVEDV obtained from QBS were compared with those from QGS, respectively. The intra- and inter-observer reproducibilities were excellent for LVEF, LVEDV, RVEF and RVEDV measured with QBS (r = 0.88 to 0.96, p < 0.01), while the biases in the measurements of RVEF and RVEDV were relatively large. LVEF obtained from QBS correlated significantly with those from FPP and GBP, while RVEF from QBS did not. LVEF and LVEDV obtained from QBS were significantly correlated with those from QGS, but the regression lines were not close to the lines of identity. In conclusion, the measurements of LVEF and LVEDV with QBS have good reproducibility and are useful clinically, while those of RVEF and RVEDV are less useful compared with LVEF and LVEDV. The algorithm of QBS for the measurements of RVEF and RVEDV remains to be improved.

Adult↗

PubMed2006

Correlation between pharmacological efficacy of cyclosporine A and tacrolimus, evaluated by lymphocyte immunosuppressant-sensitivity test (LIST) with MTT assay procedure in renal transplant recipients.

The dose of calcineurin inhibitors in renal transplantation has been adjusted, based on the therapeutic drug monitoring data. However, the data do not always correlate with clinical drug efficacy. In vitro response of peripheral-blood mononuclear cells to immunosuppressive drugs is reported to correlate with the recipient-response to therapeutic efficacy of the drug. We report, here, usefulness of a lymphocyte immunosuppressant sensitivity test for the estimation of individual drug sensitivity in renal transplant recipients. The LIST we have developed includes MTT assay procedures without the use of radioisotope-labeled compounds, which is convenient for general hospital use. Utilizing this procedure, we compared the pharmacological efficacy between cyclosporine A and tacrolimus in 41 renal transplant recipients.

Adult↗

PubMed2006

A selective inhibitor of Na+/Ca2+ exchanger, SEA0400, preserves cardiac function and high-energy phosphates against ischemia/reperfusion injury.

The Ca2+ overload by Ca2+ influx via Na+/Ca2+ exchanger (NCX) is a critical mechanism in myocardial ischemia/reperfusion injury. We investigated protective effects of a novel selective inhibitor of NCX, SEA0400, on cardiac function and energy metabolism during ischemia and reperfusion. Langendorff-perfused rat hearts were exposed to 35 minutes global ischemia and 40 minutes reperfusion. Using 31P nuclear magnetic resonance spectroscopy, cardiac phosphocreatine (PCr), ATP, and pHi were monitored. SEA0400 did not change the basic cardiac function, but improved the recovery of left ventricular developed pressure (LVDP) after reperfusion (27.6 +/- 4.9 mm Hg in control, 101.2 +/- 19.3 mm Hg in 0.1 microM, and 115.5 +/- 13.3 mm Hg in 1 microM SEA0400, means +/- SE, n = 6, P < 0.05). SEA0400 reduced left ventricular end-diastolic pressure and increased coronary flow after reperfusion. SEA0400 improved the recoveries of cardiac phosphocreatine and ATP after reperfusion, but did not affect pHi. There were significant linear correlations between left ventricular developed pressure and cardiac phosphocreatine (r = 0.79, P < 0.05), and left ventricular developed pressure and ATP (r = 0.80, P < 0.05). However, SEA0400 increased the incidence and duration of reperfusion ventricular arrhythmias. SEA0400 added only after reperfusion also improved both the contractile function and energy metabolism. It is concluded that the selective inhibition of NCX may be effective to preserve high-energy phosphates and to improve cardiac function after reperfusion, but may not be able to prevent fatal arrhythmias.

Action Potentials↗

PubMed2006

Prognostic significance of night-time, early morning, and daytime blood pressures on the risk of cerebrovascular and cardiovascular mortality: the Ohasama Study.

OBJECTIVE: To clarify whether high blood pressure (BP) at a particular time of day is associated with cerebrovascular and cardiovascular mortality risk. METHODS: Cerebrovascular and cardiovascular mortality in 1360 individuals aged 40 years and older in Ohasama, Japan, was followed for an average of 10.6 years. We used 2-h moving averages of the BP (a total of 24 average BP measurements for two consecutive hours based on four BP readings taken every 30 min) to compare the predictive power of BP taken during a 24-h period given the same number of measurements. The associations between cerebrovascular and cardiovascular mortality risk and the 2-h moving averages of systolic blood pressure (2 h-SBP) recorded over 24 h were analysed using a Cox proportional hazards model after adjusting for possible confounding factors. RESULTS: The total cerebrovascular and cardiovascular mortality risk was significantly associated with elevated 2 h-SBP recorded during the night and early morning periods. Haemorrhagic stroke mortality was significantly associated with elevated daytime 2 h-SBP. Cerebral infarction mortality and heart disease mortality were significantly associated with elevated night-time 2 h-SBP. CONCLUSION: High BP at different times of day were associated with different subtypes of cerebrovascular and cardiovascular mortality risk.

Adult↗

PubMed2006

Introversion associated with large differences between screening blood pressure and home blood pressure measurement: The Ohasama study.

OBJECTIVE: To explore the effect of personality on screening blood pressures measured in clinical settings and home blood pressure measurements. METHODS: From 1997 to 1999, 699 participants underwent screening and home blood pressure measurements and completed the Japanese version of the short-form Eysenck personality questionnaire. An increased screening blood pressure was defined as screening blood pressure > or = 140/90 mmHg and an increased home blood pressure was defined as home blood pressure > or = 135/85 mmHg. RESULTS: Participants with lower extroversion scores (i.e., introversion) showed a greater difference between screening and home systolic blood pressure. The association between introversion and differences was statistically significant, even after adjustment for other possible factors (younger age, female, wide screening pulse pressure, never smoked, and no antihypertensive medication). The adjusted means of SBP differences were 7.3 and 4.4 mmHg among the lowest and highest extroversion quartiles, respectively (P for trend = 0.02). Other personality scores (psychoticism or neuroticism) were not associated with screening and home blood pressure differences. The incorporation of an extroversion score in the basic model consisting of the above factors that affected the difference between screening and home blood pressure slightly improved the prediction of a high home blood pressure. The area under the receiver operating characteristic curve increased by 0.037 among participants with high screening blood pressure and 0.006 for those with normal screening blood pressure compared with the basic model. CONCLUSION: Physicians may need to be aware of 'introverted' patients who have high blood pressure in clinic settings, because they have the potential for 'white-coat' hypertension.

Aged↗

PubMed2006

Prevalence of prostatitis-like symptoms in Japanese men: Population-based study in a town in Hokkaido.

AIM: To determine the prevalence of prostatitis-like symptoms in Japanese men living in one town. METHODS: A cross-sectional and population-based study was performed in a town that had 6385 men aged from 20 to 79 years. We sent two questionnaires, the validated Japanese version of the National Institutes of Health Chronic Prostatitis Symptom Index and the International Prostate Symptom Score (I-PSS) with questions about individual medical information, to 1424 randomly selected community-indwelling men. Subjects were defined as having prostatitis-like symptoms if they complained of perineal and/or ejaculatory pain or discomfort and their total pain score was four or greater. RESULTS: A total of 512 men (36%) responded completely to the questionnaires. Of the 512 responders, 25 men (4.9%) were identified as having prostatitis-like symptoms. Prevalence of symptoms was the same in men aged younger than 50 years (5.0%) as those 50 years and older (4.8%). The I-PSS score was 10.8 in men with prostatitis-like symptoms, which was higher than in those without symptoms. CONCLUSIONS: Prevalence of prostatitis-like symptoms was 4.9% in randomly selected men. International comparison of prevalence of the symptoms may contribute to further understanding of chronic prostatitis.

Adult↗

PubMed2006

Comparison between compliance of fluticasone propionate diskhaler and of fluticasone propionate diskus in adult bronchial asthma patients.

BACKGROUND AND OBJECTIVES: Because inhaled corticosteroids (ICS) play a central role in the management of asthma, new drug delivery systems for fluticasone propionate, Diskhaler (FPdh) and Diskus (FPdk), were developed. However, few studies have focused on compliance with these drug delivery systems, which can influence drug efficacy. Hence, we compared compliance with FPdk versus that with FPdh. METHODS: Data were obtained from a survey of pharmacists dispensing anti-asthmatic drugs to adult asthma patients who visited participating pharmacies between October 2002 and November 2003. Patients were limited to regular users of FPdh or FPdk whose medication had not been changed for >6 months before the survey. Compliance and daily administration frequency of ICS were evaluated on the basis of pharmaceutical records. Data on asthma status and various other factors affecting ICS compliance were obtained by questionnaire. RESULTS: Data were acquired on 337 patients. There were no significant differences in gender, age, and duration between the FPdk and FPdh groups. Although FPdk compliance was significantly higher than that of FPdh, conversely there was no significant difference in daily dose and administration frequency between the 2 groups. Furthermore, there was no significant difference in the rate of concomitant drug and in various influencing factors associated with drug compliance. Regarding compliance of concomitant drug, that of oral sustained-released theophylline was significantly lower in FPdk versus FPdh users. CONCLUSION: In the area of drug compliance, FPdk is superior to FPdh. Although the reason for this is unclear, it is probably due to the characteristics of FPdk itself.

Administration, Inhalation↗

PubMed2006

Arrhythmogenic effects of arsenic trioxide in patients with acute promyelocytic leukemia and an electrophysiological study in isolated guinea pig papillary muscles.

BACKGROUND: Arsenic trioxide (As(2)O (3)) is a new promising regimen for patients with a relapse of acute promyelocytic leukemia (APL), but causes life-threatening arrhythmias. This study aimed to investigate the incidence and mechanism of arrythmogenesis caused by As(2)O(3). METHODS AND RESULTS: Standard 12-lead ECGs were monitored throughout As(2)O(3) therapy in 20 APL patients. As(2)O (3) (0.15 mg/kg) significantly prolonged the corrected QT interval (QTc: 445+/-7 to 517+/-17 ms, means+/-SE, p<0.01), and also increased the QTc dispersion and transmural dispersion of repolarization. Non-sustained ventricular tachycardias and torsades de pointes occurred in 4 and 1 patients, respectively. The action potentials and isometric contraction were measured in guinea pig papillary muscles during As(2)O (3) perfusion (350 micromol/L). The action potential duration was prolonged (APD(90): 150+/-11 to 195+/-12 ms at 60 min, p<0.01, n=5) and perfusion of As(2)O(3) in a low K(+) solution with a low stimulation rate augmented the prolongation of APD, and provoked early after-depolarizations and triggered activities. The prolonged exposure to As(2)O(3) induced muscle contracture, aftercontractions, triggered activities and electromechanical alternans. Tetrodotoxin or butylated hydroxytoluene partially prevented the As(2)O(3)-induced prolongation of APD. CONCLUSIONS: The prolonged QTc and spatial heterogeneity are responsible for the As(2)O(3)-induced ventricular tachyarrhythmias. In addition to prolongation of the APD, cellular Ca(2+) overload and lipid peroxidation might contribute to the electrophysiological abnormalities caused by As(2)O(3).

Action Potentials↗

PubMed2006

Changes of blood biochemical values in ponies recovering from hyperlipemia in Japan.

Hyperlipemia in horses is a disorder of lipid metabolism peculiar to ponies. This study reports changes of blood biochemical values from the acute to the postconvalescent phases in 3 Shetland ponies with hyperlipemia in Japan. Diseased ponies (all 7 to 9 years old, in late pregnancy, and obese) were fed in the same farm. The periods of their hospitalizations ranged from 30 to 45 days. Twelve well-conditioned ponies (3 to 13 years old) around parturition were used to establish baseline values for blood test results. Main clinical findings in the affected ponies were depression, dysphagia, anorexia, ventral edema and milky-appearing plasma. Hypertriglyceridemia (40- to 70-fold rise of controls) was found in the acute phase of the disease in the affected ponies, and was derived from increased very-low density lipoproteins. Aspartate transaminase and gamma-glutamyl transpeptidase activities, blood urea nitrogen, and creatinin concentrations were increased in acute ponies compared to controls, suggesting impairment of liver and kidney functions. However, these values gradually recovered until the end of postconvalescent phase. Hyperinsulinemia was observed in the acute phase of the hyperlipemia of all affected ponies. And an exaggerated insulin response to intravenous glucose was observed in the 2 ponies given intravenous glucose tolerance tests. These findings suggest decreased insulin sensitivity in hyperlipemic ponies.

Animals↗

PubMed2006

Association of maternal smoking during pregnancy and infant neurobehavioral status.

The association of maternal smoking during pregnancy with neurobehavioral status was examined in 344 Japanese infants. Based on a questionnaire, their mothers were classified into three groups, Nonsmokers, Exsmokers, and Smokers. The Neonatal Behavioral Assessment Scale was administered three days after birth. Among the three groups, on the seven clusters and their 28 behavioral subscales there were no significant differences. The infants of Smokers had lower scores than those of Exsmokers and Nonsmokers on two behavioral items, general tone and peak of excitement. General tone remained significant after adjustment for covariates.

Adult↗

PubMed2005

Endoplasmic reticulum Ca2+ depletion induces endothelial cell apoptosis independently of caspase-12.

OBJECTIVE: Apoptosis of endothelial cells is considered an initial step in the development of atherosclerosis. Recent studies have indicated that depletion of the endoplasmic reticulum (ER) Ca(2+) content plays an important role in apoptosis. Caspase-12 is a key signal in ER stress-induced apoptosis. However, it is not known whether the depletion of ER Ca(2+) is linked to caspase-12 signalling in endothelial cells. Here we have investigated the interaction of Ca(2+) signalling and caspase-12 cleavage in apoptosis of endothelial cells. METHODS: Cytosolic Ca(2+) concentration ([Ca(2+)](i)) of primary porcine aortic endothelial cells was measured using fura-2/AM. Apoptosis was assessed by DNA fragmentation, and cleavage of caspase-12 using Western blotting techniques. RESULTS: Thapsigargin (5 microM), an inhibitor of the ER Ca(2+)-ATPase, depleted ER Ca (2+) content, increased [Ca(2+)](i), cleaved caspase-12, and induced apoptosis. Bradykinin (10 nM) also increased [Ca(2+)](i) but did not cleave caspase-12 or induce apoptosis. However, when intracellular Ca(2+) was chelated with BAPTA/AM (100 microM), bradykinin caused ER Ca(2+) depletion and apoptosis without accompanying caspase-12 cleavage. A non-selective caspase inhibitor, z-VAD.fmk (100 microM), inhibited apoptosis and cleavage of caspase-12 stimulated by thapsigargin, while a calpain inhibitor, MDL 28170 (120 microM), inhibited caspase-12 cleavage but not apoptosis. CONCLUSIONS: Thus, increases in intracellular Ca(2+) concentration are not sufficient for the induction of apoptosis in endothelial cells, and ER Ca(2+) depletion appears to induce apoptosis independently of caspase-12.

Amino Acid Chloromethyl Ketones↗

PubMed2005

Prognostic significance for stroke of a morning pressor surge and a nocturnal blood pressure decline: the Ohasama study.

There is continuing controversy over whether the pattern of circadian blood pressure (BP) variation that includes a nocturnal decline in BP and a morning pressor surge has prognostic significance for stroke risk. In this study, we followed the incidence of stroke in 1430 subjects aged > or =40 years in Ohasama, Japan, for an average of 10.4 years. The association between stroke risk and the pattern of circadian BP variation was analyzed with a Cox proportional hazards model after adjustment for possible confounding factors. There was no significant association between total stroke risk and the nocturnal decline in BP (percentage decline from diurnal level) or between total stroke risk and the morning pressor surge. The cerebral infarction risk was significantly higher in subjects with a <10% nocturnal decline in BP as compared with subjects who had a > or =10% nocturnal decline in BP (P=0.04). The morning pressor surge was not associated with a risk of cerebral infarction. On the other hand, an increased risk of cerebral hemorrhage was observed in subjects with a large morning pressor surge (> or =25 mm Hg; P=0.04). Intracerebral hemorrhage was also observed more frequently in extreme dippers (those with a > or =20% nocturnal decline in BP) than dippers (those with a 10% to 19% decline; P=0.02). A disturbed nocturnal decline in BP is associated with cerebral infarction, whereas a large morning pressor surge and a large nocturnal decline in BP, which are analogous to a large diurnal increase in BP, are both associated with cerebral hemorrhage.

Aged↗

PubMed2005

Subclinical effects of prenatal methylmercury exposure on cardiac autonomic function in Japanese children.

OBJECTIVES: The subclinical effects of prenatal exposure to methylmercury from fish consumption on the cardiac autonomic function were assessed in 136 Japanese 7-year-old children recruited for this study. METHODS: Samples of child's hair and dry umbilical cord preserved were collected, and hair mercury and cord tissue methylmercury concentrations were determined as current and prenatal exposure biomarkers, respectively. Cardiac autonomic indicators of parasympathetic and sympathetic activities were calculated from the electrocardiographic RR intervals measured. RESULTS: In the children, the cord tissue methylmercury (0.017-0.367, median 0.089 microg/g) was not significantly correlated with the hair mercury (0.43-6.32, median 1.66 microg/g). The cord tissue methylmercury was related negatively to parasympathetic components of cardiac autonomic indicators (P < 0.05) and positively to sympathovagal indices (P < 0.05), even after correction for possible confounders such as age and sex, although the hair mercury was not significantly correlated with any cardiac autonomic indicators. CONCLUSIONS: Despite the potential limitations involved in the retrospective study, these findings suggest that prenatal methylmercury exposure (median of estimated maternal hair mercury at parturition, 2.24 microg/g) may be associated with reduced parasympathetic activity and/or sympathovagal shift.

Animals↗