Risk factors for occupational accidents in agricultural enterprises in Japan

In Japan, the agricultural working environment has undergone significant changes from self-employment to enterprises and employees. As the structure of the agricultural industry changes, there has been a growing interest in occupational health and safety because agriculture is a hazardous industry. However, the public is not aware of the actual situation regarding occupational accidents in agricultural enterprises because most Japanese farmers are not necessarily required to report occupational accidents. The aim of this study is to explore the risk factors regarding occupational accidents for Japanese agricultural employees. We conducted a cross-sectional study among 1,606 employees at 101 agricultural enterprises in Japan. Information on occupational accidents, personal characteristics, and working conditions was collected by questionnaires. A total of 337 valid responses were obtained. Of these respondents, 104 (30.9%) experienced occupational accidents. Multiple logistic regression analysis revealed that permanent employment (OR 3.67, 95% CI, 1.84-7.33), pesticide use (OR 2.61, 95% CI, 1.52-4.47), and long working hours (OR 1.76, 95% CI, 1.15-2.68) were associated with the risk of occupational accidents. This study revealed the risk factors for occupational accidents for Japanese agricultural employees. It is suggested that work-hour restrictions for permanent employees might contribute to reducing occupational accidents.

Leisure-time physical activity in youth as a predictor of adult leisure physical activity among Japanese workers: a cross-sectional study

Background

Workers in Japan are not sufficiently active; however, it remains unclear how their leisure-time physical activity habits may be developed. This cross-sectional study investigated the relationship of age- and intensity-specific leisure-time physical activity in youth to adulthood leisure-time physical activity habits among Japanese workers.

Methods

In 2012, 968 workers (333 males and 635 females) from three companies and six hospitals in the Tokai region of Japan agreed to complete and submit a self-administered questionnaire. Intensity-specific leisure-time physical activity at ages 12 and 20 years was assessed retrospectively, and workers’ current participation in regular leisure-time physical activity was assessed as an outcome measure. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis.

Results

Mean ages for males and females were 40 and 37 years, respectively. Strenuous leisure-time physical activity at age 12 years was significantly positively associated with adulthood participation in leisure-time physical activity among male workers [adjusted OR (95% CI) = 2.29 (1.02, 5.14)]. Additionally, both strenuous and moderate physical activity at age 20 years was significantly positively associated with participation in regular leisure-time physical activity in adulthood among males and females.

Conclusions

Our results suggest that some leisure-time physical activity in youth may predict adult workers’ participation in regular leisure-time physical activity in Japan. Encouragement of leisure-time physical activity in youth could therefore be an effective measure to develop adult leisure-time physical activity habits among workers.

Association between physical activity and sleep-disordered breathing in male Japanese workers: a cross-sectional study

BACKGROUND

Whether physical activity reduces the risk of sleep-disordered breathing (SDB) for non-obese people remains unclear. The present cross-sectional study examined the association between physical activity and SDB among non-obese male Japanese workers.

METHODS

All 200 workers in a company in Tokyo, Japan, who drove a motor vehicle as part of their job, were invited to be screened for SDB to prevent traffic accidents. Of these, 195 agreed to participate in this study. The number of apnea and hypopnea episodes occurring during one night was measured using a single-channel airflow monitor to obtain an individual respiratory disturbance index (RDI). SDB was defined as RDI ≥15 apneas/hypopneas/h. Non-obese males (body mass index <30 kg/m²) were included in the analysis. Unconditional logistic regression analysis was used to calculate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for SDB by physical activity level tertile, as measured by the International Physical Activity Questionnaire.

RESULTS

The prevalence of SDB was 26.9%. The unadjusted analysis showed a significant inverse association between physical activity and SDB: crude ORs for the tertiles of physical activity were 1.00 (low), 1.58 (middle), and 0.27 (high) (95% CI 0.08-0.88; P for trend = 0.007). However, this association was attenuated after adjusting for covariates: Adjusted ORs were 1.00 (low), 1.65 (middle), and 0.41 (high) (95% CI 0.10-1.61; P for trend = 0.11).

CONCLUSIONS

In a cross-sectional study among non-obese male workers in Japan, we found no significant association between physical activity and SDB.

Effects of mineralocorticoid receptor antagonists in patients with hypertension and diabetes mellitus: a systematic review and meta-analysis

Blood pressure (BP) control is important to ameliorate cardiovascular events in patients with diabetes mellitus (DM). However, achieving the target BP with a single drug is often difficult. The objective of this study was to evaluate the antihypertensive effects of mineralocorticoid receptor antagonists (MRAs) as add-on therapy to renin–angiotensin system (RAS) inhibitor(s) in patients with hypertension and DM. Studies were searched through October 2014 in MEDLINE, Embase and the Cochrane Central Register of Controlled Trials. Randomized, controlled trials or prospective, observational studies regarding concomitant administration of MRA and RAS inhibitor(s) in patients with DM were included. Articles were excluded if the mean systolic BP (SBP) was <130 mm Hg before randomization for interventional studies or at baseline for prospective cohort studies. We identified nine eligible studies (486 patients): five randomized placebo-controlled trials; three randomized active drug-controlled trials; and one single-arm observational study. The mean differences in office SBP and diastolic BP (DBP) between the MRA and placebo groups were −9.4 (95% confidence interval (CI) −12.9 to −5.9) and −3.8 (95% CI, −5.5 to −2.2) mm Hg, respectively. Subgroup analysis results for study type, age, baseline office SBP and follow-up duration were similar to those of the main analysis. MRA mildly increased serum potassium (0.4 mEq l⁻¹; 95% CI, 0.3–0.5 mEq l⁻¹). A consistent reduction of albuminuria across these studies was also demonstrated. MRA further reduced SBP and DBP in patients with hypertension and DM already taking RAS inhibitors. Serum potassium levels should be monitored to prevent hyperkalemia.

Cost-benefit analysis of comprehensive mental health prevention programs in Japanese workplaces: a pilot study

We examined the implementation of mental health prevention programs in Japanese workplaces and the costs and benefits. A cross-sectional survey targeting mental health program staff at 11 major companies was conducted. Questionnaires explored program implementation based on the guidelines of the Japanese Ministry of Health, Labor and Welfare. Labor, materials, outsourcing costs, overheads, employee mental discomfort, and absentee numbers, and work attendance were examined. Cost-benefit analyses were conducted from company perspectives assessing net benefits per employee and returns on investment. The surveyed companies employ an average of 1,169 workers. The implementation rate of the mental health prevention programs was 66% for primary, 51% for secondary, and 60% for tertiary programs. The program's average cost was 12,608 yen per employee and the total benefit was 19,530 yen per employee. The net benefit per employee was 6,921 yen and the return on investment was in the range of 0.27-16.85. Seven of the 11 companies gained a net benefit from the mental health programs.

Sick building syndrome by indoor air pollution in Dalian, China

This study assessed subjective symptoms related to indoor concentrations of chemicals among residents in a housing estate in Dalian, China, where indoor air pollution by interior decoration materials has recently become a major health problem. Fifty-nine males and 50 females were surveyed for their symptoms related to sick building syndrome. Formaldehyde (HCHO), NO₂, and volatile organic compounds (VOCs) in their dwellings were collected using a diffusion sampler and measured by GC/MS. For residents with one or more symptoms in the past, HCHO, butanol or 1,2-dichloroethane concentrations were significantly greater in their bedrooms or kitchens compared with those of subjects without previous symptoms. For residents with one or more symptoms at the time of the study, 1,1,1-trichloroethane, xylene, butanol, methyl isobutyl ketone, and styrene concentrations in their bedrooms or kitchens were significantly greater compared with those of residents without symptoms. HCHO, NO₂, and VOCs were detected in all rooms, but their levels were lower than the guideline values except for HCHO in two rooms. Chemical substances from interior decoration materials at indoor air levels lower than their guideline values might have affected the health status of residents.

Prenatal exposure to arsenic and its effects on fetal development in the general population of Dalian

To evaluate prenatal exposure to arsenic in the general population and its effects on birth size, we conducted a cross-sectional study in Dalian, China. Arsenic concentration in maternal and cord blood was detected by inductively coupled plasma-mass spectrometry and its effects on birth size were analyzed by multivariate analysis and multiple linear regression analysis. Arsenic concentrations in cord blood were significantly lower than those in maternal blood. A significant positive correlation was shown between maternal and cord blood arsenic concentrations. Maternal arsenic concentration was negatively associated with birth weight, height and chest circumference, and fetal arsenic concentration was negatively associated with head circumference. Our results indicate that arsenic exposure at environmental levels in uterus may pose adverse effects on fetal development.

Early pregnancy blood lead and spontaneous abortion

Although evidence tends to suggest that high levels of lead exposure increase the risk of spontaneous abortion, we do not yet know whether moderate- to low-level exposure elevates risk. Among 351 women (aged 16 to 35 years, with single pregnancies) who were registered for a longitudinal study, 15 (4.3%) women experienced spontaneous abortion after the 12th week of gestation and before the 20th week. We collected participants' blood samples during the first trimester of pregnancy (8-12 weeks) for lead measurement by inductively coupled plasma-mass spectrometry. Mean ± standard deviation of blood lead was 3.8 ± 2.0 μg/dl (range 1.0-20.5 μg/dl) with a geometric mean of 3.5 μg/dl. Mean blood lead concentrations did not differ significantly between spontaneous abortion cases and ongoing pregnancies (3.51 ± 1.42 and 3.83 ± 1.99 μg/dl, respectively). The findings suggest that in apparently healthy women, low blood lead levels (mean < 5 μg/dl) measured in early pregnancy may not be a risk factor for spontaneous abortion.

Decrease in birth weight and gestational age by arsenic among the newborn in Shanghai, China

OBJECTIVES

To assess the effects of trace metals on birth weight and gestational age among newborn babies of mothers without occupational exposure.

METHODS

The subjects examined were 142 newborn babies (71 males and 71 females) delivered at two university hospitals in Shanghai, China and their parents. Relationships of newborn birth weight and gestational age to concentrations of arsenic, lead, cadmium, manganese, zinc, and cobalt in maternal and cord blood were investigated.

RESULTS

Birth weight was 3379.5 +/- 440.8 (2090-4465) g and the gestational age was 39.7 +/- 1.3 (35-43) weeks. Stepwise regression analysis indicated that, in the male newborn, birth weight and gestational age were inversely related to the logarithm arsenic concentration (4.13 +/- 3.21 microg/l) in mothers' whole blood.

CONCLUSION

Arsenic might have a negative influence on newborn birth weight and gestational age at a relatively low exposure level. This effect was observed in male but not female babies, suggesting a sex differential in susceptibility to arsenic at an early stage of development. Although birth weight is believed to be related to gestational age, arsenic may directly affect both birth weight and gestational age.

Lead and other trace metals in preeclampsia: a case-control study in Tehran, Iran

To assess the effects of environmental exposures to trace metals on the incidence of preeclampsia, concentrations of lead (Pb), antimony (Sb), manganese (Mn), mercury, cadmium, cobalt and zinc in umbilical cord blood (UCB) and mother whole blood (MWB) were measured in 396 postpartum women without occupational exposure to metals in Tehran, Iran, using inductively coupled plasma mass spectrometry. Mother's ages ranged from 15 to 49 (mean 27) years. Preeclampsia was diagnosed in 31 subjects (7.8%). Levels of Pb, Sb and Mn in UCB were significantly higher in preeclampsia cases [mean+/-SD of 4.30+/-2.49 microg/dl, 4.16+/-2.73 and 46.87+/-15.03 microg/l, respectively] than in controls [3.52+/-2.09 microg/dl, 3.17+/-2.68 and 40.32+/-15.19 microg/l, respectively] (P<0.05). The logistic regression analysis revealed that one unit increase in the common logarithms of UCB concentration of Pb, Sb or Mn led to increase in the risk of preeclampsia several-fold; unit risks (95% CI) were 12.96 (1.57-107.03), 6.11 (1.11-33.53) and 34.2 (1.81-648.04) for Pb, Sb and Mn, respectively (P<0.05). These findings suggest that environmental exposure to Pb, Sb and Mn may increase the risk of preeclampsia in women without occupational exposure; levels of metals in UCB to be sensitive indicators of female reproductive toxicity as compared with those in mother MWB. Further studies are necessary to confirm these findings, especially on Sb and Mn.

Relationship between increased blood lead and pregnancy hypertension in women without occupational lead exposure in Tehran, Iran

This study was conducted to assess the relationship between blood lead levels and pregnancy-induced hypertension. Participants were 110 pregnant women, of whom 55 were hypertensive, 27 +/- 5.6 yr of age (mean +/- standard deviation) (range = 17-40 yr); the other 55 women were age- and gravidity-matched normotensive controls. Participants were selected on the basis of their medical history and the results of a questionnaire-based interview. Subjects were at gestational ages 37 +/- 2.5 wk (range = 30-41 wk) and were not occupationally exposed to lead. Blood samples were collected within 24 hr after delivery, and blood lead levels were measured. For the hypertensive cases, blood lead levels were 5.7 +/- 2 microg/dl (range = 2.2-12.6 microg/dl [0.27 +/- 0.10 micromol/l; range = 0.11-0.60 micromol/l]), which were significantly higher than those of the control group (i.e., 4.8 +/- 1.9 microg/dl; range = 1.9-10.6 microg/dl [0.23 +/- 0.09 micromol/l; range = 0.09-0.51 micromol/l]). There were no significant differences in blood lead concentrations among hypertensive subjects with proteinuria (n = 30) and those without proteinuria (n = 25). Results of this study indicated that low-level lead exposure may be a risk factor for pregnancy hypertension.

Effects of pesticides on the peripheral and central nervous system in tobacco farmers in Malaysia: studies on peripheral nerve conduction, brain-evoked potentials and computerized posturography

We examined the effects of pesticides on the central and peripheral nervous system in the setting of a tobacco farm at a developing country. Maximal motor and sensory nerve conduction velocities (MCV and SCV, respectively) in the median, sural and tibial nerves, postural sway, and brain-evoked potentials (auditory event-related and visual-evoked potentials) were measured in 80 male tobacco farmers and age- and sex-matched 40 controls in Kelantan, Malaysia. Median SCV (finger-wrist) in farmers using Delsen (mancozeb, dithiocarbamate fungicide), who showed significant decrease of serum cholinesterase activities, were significantly lower compared with the controls. Sural SCV in farmers using Fastac (alpha-cypermethrin, pyrethroid insecticide) and median MCV (elbow-wrist) in farmers using Tamex (butralin, dinitroaniline herbicide) were significantly slowed compared with their respective controls. In Delsen (mancozeb, dithiocarbamate) users, the power of postural sway of 0-1 Hz was significantly larger than that in the controls both in the anterior-posterior direction with eyes open and in the right-left direction with eyes closed. The former type of sway was also significantly increased in Tamaron (methamidophos, organophosphorus insecticide) users. In conclusion, nerve conduction velocities and postural sway seem to be sensitive indicators of the effects of pesticides on the central and peripheral nervous system.

Increase of olfactory threshold in plating factory workers exposed to chromium in Korea

To disclose the effects of chromium (Cr) on olfactory function, olfactory threshold tests were conducted on 27 male plating workers (Cr workers) with signs and symptoms of olfactory irritation but without nasal septum perforation or ulcer and on 34 male control subjects in Korean plating factories. The Cr workers had been exposed to Cr fume for 0.9 to 18.2 (mean 7.9) years; their blood Cr concentrations (0.16-3.69, mean 1.29 microg/dl) were significantly higher than those of the 34 control subjects (0.04-1.95, mean 0.55 microg/dl). Scores on recognition thresholds among the Cr workers were significantly higher than those of the control subjects (p < 0.05) and related positively and significantly to the exposure periods of the 27 Cr workers (p < 0.05). Olfactory thresholds were not significantly different between the Cr workers with and without nasal signs or symptoms, except that the scores on the recognition threshold were significantly higher in those experiencing difficulty with smell (p < 0.05). It is suggested that olfactory threshold is affected by Cr without development of nasal septum perforation or ulceration.

Sudden cardiac arrest immediately after aortic cross clamping during abdominal aortic aneurysm repair

We report a case of sudden cardiac arrest immediately after aortic cross clamping during surgery for infrarenal abdominal aortic aneurysm in a patient with coronary artery disease. The cause, treatment, and necessary monitoring for the case are discussed.

Square wave voltammetric sensing of uric acid using the self-assembly of mercaptobenzimidazole

The self-assembled monolayer of a heterocyclic thiol, mercaptobenzimidazole (MBI) on gold (Au) electrode is successfully utilized for the voltammetric sensing of uric acid (UA). The self-assembly of MBI separates the voltammetric signal of UA from the interfering ascorbate (AA). Selective detection of UA in the presence of a large excess of AA or the simultaneous detection of UA and AA is achieved at the MBI monolayer-modified electrode. This electrode can detect as low as 1 microM of UA in the presence of 100-fold excess of AA with excellent reproducibility. The practical utility of the electrode is demonstrated by measuring the concentration of UA in human serum.

Association of low job control with a decrease in memory (CD4+ CD45RO+) T lymphocytes in Japanese middle-aged male workers in an electric power plant

To clarify the relationship between perceived job stress and lymphocyte subpopulations, a cross-sectional study was conducted in 231 male electric power plant workers (aged 40 to 60, mean 46 years). Job stress, i.e., job control, job demands, and social support at work, was assessed by means of the Japanese version of the Job Content Questionnaire. Blood samples were taken from all the workers, and numbers of CD4+ T lymphocyte subpopulations, total CD4+ T, T (CD3+) lymphocytes, CD16CD56+ natural killer (NK) cells, total lymphocytes, and white blood cells were determined. After controlling for age, number of cigarettes smoked per day, alcohol drinking, frequency of regular exercise, job demands, and social support at work by the partial correlation coefficients, numbers of memory (CD4+ CD45RO+) T, total CD4+ T, and total T (CD3+) lymphocytes were positively correlated with job control (p<0.05). Neither job demands nor social support at work showed significant correlations with lymphocyte subpopulations. It is suggested that lower job control is associated with a decrease in the number of CD4+ CD45RO+ T lymphocytes in male middle-aged workers.

Assessment of the mutations of p53 suppressor gene and Ha- and Ki-ras oncogenes in malignant mesothelioma in relation to asbestos exposure: a study of 12 American patients

In our previous study, we found no genetic alteration in exons 1 and 2 of Ha- and Ki-ras oncogenes nor in exons 5 to 9 of the p53 suppressor gene in seven Japanese malignant mesothelioma patients exposed to asbestos. To examine further whether malignant mesothelioma due to asbestos has genetic alterations in the p53 suppressor gene and in Ha- and Ki-ras oncogenes, we analyzed point mutations of these genes in paraffin embedded operative open biopsied samples of the primary tumor of malignant mesothelioma in twelve American patients. The genetic analysis was conducted by the PCR-SSCP (polymerase chain reaction single-strand conformation polymorphism) method in all patients and by sequencing analysis of DNA bases in the two patients with suspected gene mutation. The analysis of the p53 suppressor gene showed an amino acid converting mutation of exon 7 in one patient and a polymorphism of exon 6 in another patient; the former patient was a heavy smoker with a biphasic cell type. No genetic alteration was found in exons 1 and 2 of Ha- and Ki-ras oncogenes in any of the patients. The results suggest that the effects of asbestos on the p53 suppressor gene and Ha- and Ki-ras oncogenes in malignant mesothelioma are negligible. Further studies are needed to examine whether the observed mutation of the p53 suppressor gene is due to the combined effects of asbestos and smoking or to other unknown factors.

A case of muscular hamartoma of the breast

We describe a 74-year-old female presenting with a right breast mass. She had found the mass on self-examination. Physical examination revealed a 2.2 x 2.5 cm, firm, smooth, and mobile lump in the upper medial portion of the right breast. Mammography revealed a well marginated, oval-shaped, and isodense nodule. Calcification was not evident. On ultrasonography, the lesion was 17 x 18 x 9 mm and located 5 mm below the overlying skin. Excisional biopsy under local anesthesia was performed. The tumor was easily excised. Histopathologically, the lesion was composed of intersecting bundles of spindle-shaped smooth muscle cells, and involved peripheral ducts and fat tissue. Immunohistochemical staining showed positivity for alpha-smooth muscle actin (SMA), but was negative for S-100 protein, myoglobin, keratin, and vimentin. From these findings a muscular hamartoma of the breast, a rare subtype of hamartoma, was diagnosed.

Drastic up-regulation of Fcepsilonri on mast cells is induced by IgE binding through stabilization and accumulation of Fcepsilonri on the cell surface

It has been shown that IgE binding to FcepsilonRI on mast cells results in increased FcepsilonRI expression, which in turn enhances IgE-dependent chemical mediator release from mast cells. Therefore, prevention of the IgE-mediated FcepsilonRI up-regulation would be a promising strategy for management of allergic disorders. However, the mechanism of IgE-mediated FcepsilonRI up-regulation has not been fully elucidated. In this study, we analyzed kinetics of FcepsilonRI on peritoneal mast cells and bone marrow-derived mast cells. In the presence of brefeldin A, which prevented transport of new FcepsilonRI molecules to the cell surface, levels of IgE-free FcepsilonRI on mast cells decreased drastically during culture, whereas those of IgE-bound FcepsilonRI were stable. In contrast, levels of FcgammaRIII on the same cells were stable even in the absence of its ligand, indicating that FcepsilonRI alpha-chain, but not beta- and gamma-chains, was responsible for the instability of IgE-free FcepsilonRI. As far as we analyzed, there was no evidence to support the idea that IgE binding to FcepsilonRI facilitated synthesis and/or transport of FcepsilonRI to the cell surface. Therefore, the stabilization and accumulation of FcepsilonRI on the cell surface through IgE binding appears to be the major mechanism of IgE-mediated FcepsilonRI up-regulation.

Mouse CD94 participates in Qa-1-mediated self recognition by NK cells and delivers inhibitory signals independent of Ly-49

Inhibitory receptors expressed on NK cells recognize MHC class I molecules and transduce negative signals to prevent the lysis of healthy autologous cells. The lectin-like CD94/NKG2 heterodimer has been studied extensively as a human inhibitory receptor. In contrast, in mice, another lectin-like receptor, Ly-49, was the only known inhibitory receptor until the recent discovery of CD94/NKG2 homologues in mice. Here we describe the expression and function of mouse CD94 analyzed by a newly established mAb. CD94 was detected on essentially all NK and NK T cells as well as small fractions of T cells in all mouse strains tested. Two distinct populations were identified among NK and NK T cells, CD94(bright) and CD94(dull) cells, independent of Ly-49 expression. The anti-CD94 mAb completely abrogated the inhibition of target killing mediated by NK recognition of Qa-1/Qdm peptide on target cells. Importantly, CD94(bright) but not CD94(dull) cells were found to be functional in the Qa-1/Qdm-mediated inhibition. In the presence of the mAb, activated NK cells showed substantial cytotoxicity against autologous target cells as well as enhanced cytotoxicity against allogeneic and "missing self" target cells. These results suggest that mouse CD94 participates in the protection of self cells from NK cytotoxicity through the Qa-1 recognition, independent of inhibitory receptors for classical MHC class I such as Ly-49.

Block of sodium channels by divalent mercury: role of specific cysteinyl residues in the P-loop region

Divalent mercury (Hg(2+)) blocked human skeletal Na(+) channels (hSkM1) in a stable dose-dependent manner (K(d) = 0.96 microM) in the absence of reducing agent. Dithiothreitol (DTT) significantly prevented Hg(2+) block of hSkM1, and Hg(2+) block was also readily reversed by DTT. Both thimerosal and 2,2'-dithiodipyridine had little effect on hSkM1; however, pretreatment with thimerosal attenuated Hg(2+) block of hSkM1. Y401C+E758C rat skeletal muscle Na(+) channels (mu1) that form a disulfide bond spontaneously between two cysteines at the 401 and 758 positions showed a significantly lower sensitivity to Hg(2+) (K(d) = 18 microM). However, Y401C+E758C mu1 after reduction with DTT had a significantly higher sensitivity to Hg(2+) (K(d) = 0.36 microM) than wild-type hSkM1. Mutants C753Amu1 (K(d) = 8.47 microM) or C1521A mu1 (K(d) = 8.63 microM) exhibited significantly lower sensitivity to Hg(2+) than did wild-type hSkM1, suggesting that these two conserved cysteinyl residues of the P-loop region may play an important role in the Hg(2+) block of the hSkM1 isoform. The heart Na(+) channel (hH1) was significantly more sensitive to low-dose Hg(2+) (K(d) = 0.43 microM) than was hSkM1. The C373Y hH1 mutant exhibited higher resistance (K(d) = 1.12 microM) to Hg(2+) than did wild-type hH1. In summary, Hg(2+) probably inhibits the muscle Na(+) channels at more than one cysteinyl residue in the Na(+) channel P-loop region. Hg(2+) exhibits a lower K(d) value (<1. 23 microM) for inhibition by forming a sulfur-Hg-sulfur bridge, as compared to reaction at a single cysteinyl residue with a higher K(d) value (>8.47 microM) by forming sulfur-Hg(+) covalently. The heart Na(+) channel isoform with more than two cysteinyl residues in the P-loop region exhibits an extremely high sensitivity (K(d) < 0. 43 microM) to Hg(+), accounting for heart-specific high sensitivity to the divalent mercury.

Inverted left atrial appendage

An unexpected left atrial mass was found during postoperative echocardiography in a 17-years old man following aortic valve replacement, suggesting thrombus, vegetation and neoplasm. Reoperation showed that the mass to be an inverted left atrial appendage. Left ventricular venting may cause such inversion. To prevent this complication, we suggest the use of careful monitoring and intraoperative transesophageal echocardiography.

[Aortic valve replacement for aortic valve stenosis due to congenital bicuspid aortic valve with abnormal positioning of coronary orifice, pseudotendon, and persistent left superior vena cava, report of a case]

A patient was a 65-year-old female who had a complaint of palpitation was diagnosed aortic valve stenosis due to congenital bicuspid aortic valve with pseudotendon by the echocardiographic examination. We suspected left single coronary artery by the aortography and the coronary artery angiography. Aortic valve replacement and resection of pseudotendon was performed with Carbomedics supra-annular aortic valve (21 A). During surgery, persistent left superior vena cava was detected. High-posterior take-off right coronary artery was casually detected at aortic closure. Ventricular fibrillation due to insufficient supply of cardioplegic solution at right coronary area frequently occurred after cardio-pulmonary bypass and percutaneous cardiopulmonary support was required. The patient was discharged 32 days after the operation. Preoperative and intraoperative evaluation was important in the case of aortic valvular disease.

[A case of successful reoperation for distal aortic arch pseudoaneurysm after replacement of descending aorta]

The patient was a 69-year-old man who had undergone replacement of descending aorta under close clump technique. Hoarseness occurred 8 years after the operation. Computed tomography and aortography revealed a saccular aneurysm of the distal aortic arch. During surgery, the pseudoaneurysm originated from a intimal defect close to the proximal anastomotic site of the graft. Total aortic arch replacement was successfully performed under retrograde and selective cerebral perfusion. The postoperative course has been uneventful.

Reliability of clinical judgment of patients' competency to give informed consent: a case vignette study

The competency of psychiatric patients to give informed consent is important in respecting patients' decisions as well as protecting patients from undue exploitation. A total of 176 members of the Japanese Society of Psychiatry and Neurology gave a clinical judgment in a questionnaire of competency in five case transcriptions. Their interrater reliability of competency judgment was slight (generalized kappa 0.31). Clinicians' global judgment of patients' competency was not reliable, but it may be improved by the use of a structured interview.

Establishment of antigen-specific IgE transgenic mice to study pathological and immunobiological roles of IgE in vivo

We have established transgenic mice that carry the genes coding for heavy and light chains of TNP-specific IgE. They produced high titers of TNP-specific IgE (20-40 microg/ml in serum) and their mast cells were heavily loaded with IgE. The level of FcepsilonRI expression on their mast cells was 6-8 times higher than that in non-transgenic littermates. The expression of low-affinity IgE receptor FcepsilonRII (CD23) on splenic B cells was also 6-8 times higher in the transgenic mice. Consistent with this, substantial amounts of IgE were detected on B cells in the transgenic mice. When challenged with i.v. administration of the corresponding antigen, the transgenic mice exhibited systemic anaphylactic symptoms such as a drastic drop of body temperature and extravasation of administered dye. Biphasic (immediate and delayed) ear swelling response was also elicited in a TNP-specific manner by epicutaneous antigen challenge without any prior sensitization. Thus, IgE produced in the transgenic mice was found to be biologically active to induce both local and systemic allergic reactions in vivo upon the challenge of the corresponding antigen. Taken together, the antigen-specific IgE transgenic mice established for the first time in this study appear to provide an attractive model system to study the pathological roles of IgE in acute and chronic phases of allergic inflammation as well as their immunobiological roles in vivo. They may also be useful to develop novel therapeutic strategies for atopic disorders.

Molecular cloning of the human gene STK10 encoding lymphocyte-oriented kinase, and comparative chromosomal mapping of the human, mouse, and rat homologues

LOK is a new and unique member of the STE20 family with serine/threonine kinase activity, and its expression is restricted mostly to lymphoid cells in mice. We cloned the cDNA encoding the human homologue of LOK. The amino acid sequence deduced from the cDNA shows a high similarity to that of mouse LOK, with 88% identity as a whole. The kinase domains at the N-terminus and the coiled-coil regions at the C-terminus are particularly conserved, showing 98% and 93% identity, respectively. Western blot analysis with mouse LOK-specific antibody detected 130 000 Mr LOK proteins in human and rat lymphoid cell lines and tissues. The gene encoding the LOK (STK10/Stk10) gene was mapped by fluorescence in situ hybridization to chromosome 5q35.1 in human, chromosome 11A4 in mouse, and chromosome 10q12.3 in rat. By virtue of polymorphic CA repeats found in the 3' untranslated region of the mouse Stk10 gene, the Stk10 locus was further pinpointed to chromosome 11 between D11Mit53 and D11Mit84, using the intersubspecific backcross mapping panel. These results established STK10 as a new marker of human chromosome 5 to define the syntenic boundary of human chromosomes 5 and 16 on mouse chromosome 11.

Flow cytometric diagnosis of the cell lineage and developmental stage of acute lymphoblastic leukemia by novel monoclonal antibodies specific to human pre-B-cell receptor

Three novel monoclonal antibodies (MoAbs) have been established that recognize distinct epitopes of a human pre-B-cell receptor (pre-BCR) composed of a mu heavy (muH) chain and a lambda5/VpreB surrogate light (SL) chain. HSL11 reacts with lambda5 whereas HSL96 reacts with VpreB. Intriguingly, HSL2 does not bind to each component of the pre-BCR but does bind to the completely assembled pre-BCR complex. Flow cytometric analyses with cytoplasmic staining of a panel of human cell lines showed that HSL11 and HSL96 specifically stained cell lines derived from the pro-B and pre-B-cell stages of B-cell development. In contrast, HSL2 stained exclusively cell lines derived from the pre-B-cell stage. These results prompted us to explore the possibility of clinical application of these MoAbs for the determination of the cell lineage and developmental stage of acute lymphoblastic leukemia (ALL). Whereas none of mature B-lineage ALLs (B-ALLs), T-lineage ALLs (T-ALLs), and acute myeloid leukemias analyzed were stained in the cytoplasm with these three MoAbs, the vast majority of non-B- and non-T-ALLs (53 out of 56 cases) were found positive for either lambda5, Vpre-B, or both in their cytoplasm. Among these 53 cytoplasmic SL chain-positive ALLs, 19 cases were also positive for cytoplasmic muH chain, indicative of pre-B-cell origin. Interestingly, 6 out of these 19 pre-B-ALL cases were found negative for cytoplasmic staining with HSL2. From these results, we propose a novel classification of B-ALL in which five subtypes are defined on the basis of the differential expression of SL chain, muH chain, pre-BCR, and light chain along the B-cell development.

Increase in memory (CD4+CD29+ and CD4+CD45RO+) T and naive (CD4+CD45RA+) T-cell subpopulations in smokers

To examine the effects of smoking on lymphocyte subpopulations, we measured the following cell subpopulations: CD4+ T-cell subpopulations (i.e., CD4+CD29+, CD4+ CD45RO+, and CD4+CD45RA+ cells); CD8+ T-cell subpopulations (i.e., CD8+CD11a+ and CD8+CD11b+ cells); and natural killer cell subpopulations (i.e., CD16+CD57-, CD16+CD57+, and CD16-CD57+ cells). We measured these subpopulations, together with total CD4+ T, total CD8+ T, total CD3+ T, B (CD19+), and total lymphocytes, in 10 male heavy smokers, 38 male light-to-moderate smokers, and 33 male nonsmokers. The mean ages were 30 y, 31 y, and 32 y, respectively, and ages did not vary significantly among the smokers. CD4+CD29+ and CD4+CD45RO+ (memory T) cells in heavy smokers were significantly more numerous than those in light-to-moderate smokers and nonsmokers. Also, these memory T-cell subpopulations were significantly more numerous in light-to-moderate smokers than in nonsmokers. The number of CD4+CD45RA+ (naive T) cells was significantly larger in heavy smokers than nonsmokers; numbers of CD4+CD45RO+ T and CD4+CD29+ T cells (memory T cells) were significantly correlated with daily cigarette consumption. Numbers of CD3+ T, CD4+ T, CD19+ B, and total lymphocytes in heavy smokers were significantly larger than in nonsmokers. There were significantly more CD3+ T, CD4+ T, and total lymphocytes in light-to-moderate smokers than in nonsmokers. The numbers of CD4+ T lymphocytes in heavy smokers were significantly larger than in light-to-moderate smokers. Perhaps CD4+ T cell subpopulations, especially memory T cells, are most susceptible to the effects of smoking on lymphocyte subpopulations.

[A case of tuberculous granulomatous mediastinitis and constrictive pericarditis simulating malignant mediastinal tumor]

A case is 40-year-old man. He presented anterior chest pain. Pericardial effusion was pointed out and a tuberculin skin test was positive. Tuberculous pericarditis was highly suspected, so INH and RFP were medicated. After 6-month medication pericardial effusion decreased, but right pleural effusion appeared on chest X-ray. Chest CT revealed a thickening of pericardium extend to anterior mediastinal mass. Echocardiogram revealed a pressure gradient in right ventricle, which was compressed by the thickened pericardium. We underwent median sternotomy in order to rule out neoplastic diseases. Intraoperative pathologic diagnosis was granulomatous mediastinitis and pericarditis, so we resected granuloma as much as possible to decompress the heart. Although Mycobacterium tuberculosis was not found in the resected granuloma, it was most probable pathogen. He received additional antituberculous chemotherapy for 6 months.

[Simultaneous operation of intra-descending aorta bypass grafting and brachiocephalic artery reconstruction in a patient of aortitis syndrome]

A 42-year-old woman underwent concomitant intra-descending aorta bypass grafting and brachiocephalic artery reconstruction successfully. She was diagnosed as aortitis syndrome with brachiocephalic artery obstruction, severe stenosis of descending aorta and stenosis of right upper renal artery. Chief complaint was chest oppressive feeling, but none of brain nor upper extremity ischemia. Catheterization showed 100 mmHg pressure gradient across stenosis of descending aorta and 100 mmHg pressure gradient between ascending aorta and right brachial artery. In order to relieve hypertension and prevent right head and upper extremity ischemia, concomitant vascular reconstruction was performed using woven Dacron prostheses. Hypertension had subsided postoperatively, and she was relieved from any symptom.

FK506 (tacrolimus) inhibits extravasation of lymphoid cells by abrogating VLA-4/VCAM-1 mediated transendothelial migration

Extravasation is a critical process for the physiological lymphocyte traffic as well as the hematogenous spread of malignant hemopoietic cells. Here we report that abrogation of calcineurin activity leads to in vitro transendothelial migration and in vivo infiltration of human lymphoma Nalm-6 cells, which are associated with the abrogation of the VLA-4/VCAM-1 mediated pathway. Rapamycin, which can antagonize FK506 but not CsA to inhibit calcineurin, abrogates FK-506 mediated but not CsA mediated inhibition of in vitro transendothelial migration. FK506 may exert its potent immunosuppressive action partly by inhibiting VLA-4/VCAM-1 mediated transendothelial migration or insinuation of lymphoid cells to tissues.

Intracellular Signal-transducing elements involved in transendothelial migration of lymphoma cells

To investigate the molecular mechanisms underlying transendothelial migration of tumor cells, an essential process for their hematogenous dissemination, we developed an in vitro model system that allows the separate monitoring of cell adhesion and transmigration processes. This system uses a human pre-B lymphoma cell line, Nalm-6, and a cultured mouse endothelial cell line, KOP2.16. Nalm-6 cells rapidly adhered to KOP2.16 and subsequently transmigrated underneath them. Using this model, we examined the effects on transendothelial migration, of various reagents which specifically interfere with the function of intracellular signal transduction molecules. Treatment of Nalm-6 cells with wortmannin (WMN), herbimycin A, pertussis toxin, or C3 exoenzyme of Clostridium botulinum, which specifically inhibit P13 kinase and/or myosin light chain kinase, herbimycin-sensitive tyrosine kinases, heterotrimeric G proteins, and the small G proteins, and the small G proteins rho/rac, respectively, reduced transmigration in a dose-dependent manner, Pretreatment of KOP2.16 endothelial cells with WMN also reduced transmigration in a dose-dependent manner. Binding of Nalm-6 binding to KOp2.16 was not affected, even when Nalm-6 or KOP2.16 cells were pretreated with these inhibitors, indicating that the reduction of transmigration was not due to a reduction of Nalm-6 to KOP2.16. These results also indicate that the signal transduction pathway(s) involved in transmigration can be dissociated from that of adhesion. Our results support the notion that endothelial cells are not a passive barrier in lymphoma extravasation, but that they assist lymphoma cell extravasation.

Assessment of mutations of Ha- and Ki-ras oncogenes and the p53 suppressor gene in seven malignant mesothelioma patients exposed to asbestos--PCR-SSCP and sequencing analyses of paraffin-embedded primary tumors

To examine whether malignant mesothelioma due to asbestos has genetic alterations in the Ha- and Ki-ras oncogenes or in the p53 suppressor gene, we analyzed the point mutations of these genes in paraffin-embedded autopsy samples of the primary tumors of malignant mesothelioma in seven asbestos patients who died from malignant mesothelioma. The genetic analysis was conducted by the polymerase chain reaction-single strand comformation polymorphysms (PCR-SSCP) method in all patients, and through the sequencing of deoxyribonucleic acid (DNA) bases in one patient. No genetic alterations were found in exons 1 or 2 of Ha- and Ki-ras oncogenes, or in exons 5 to 9 of the p53 gene, in any of the patients. Further studies on a larger number of patients are required to reach a definite conclusion concerning the genetic effects of asbestos on malignant mesothelioma.

Widespread expression of chondroitin sulfate-type serglycins with CD44 binding ability in hematopoietic cells

Serglycin is a family of small proteoglycans with Ser-Gly dipeptide repeats and is modified with various types of glycosaminoglycan side chains. We previously demonstrated that chondroitin sulfate-modified serglycin is a novel ligand for CD44 involved in the adherence and activation of lymphoid cells. In this study, we investigated the production and distribution of CD44 binding serglycins in various hematopoietic cells and characterized their carbohydrate side chains. Immunoprecipitation analysis using CD44-IgG and polyclonal antibody against the serglycin core peptide demonstrated that various serglycin species capable of binding CD44 are produced by a variety of hematopoietic cells including lymphoid cells, myeloid cells, and a few tumor cell lines. Glycosaminoglycans on these serglycins, which are essential for CD44 binding, are composed of chondroitin 4-sulfate or a mixture of chondroitin 4-sulfate and chondroitin 6-sulfate, but no heparin or heparan sulfate side chain was detected. The serglycins are also secreted by normal splenocytes, lymph node lymphocytes, and bone marrow cells, whereas they are secreted in very small amounts by normal thymocytes. Secretion of serglycins is greatly enhanced by mitogenic stimulation with concanavalin A or lipopolysaccharide. Our results showed that serglycin, unlike hyaluronate, is produced and secreted in a functional (CD44 binding) form by many members of the hematopoietic system including various lymphocyte subsets. Our data suggest that serglycin may serve as a major ligand for CD44 in various events in the lymphohematopoietic system.

The Ig alpha/Igbeta heterodimer on mu-negative proB cells is competent for transducing signals to induce early B cell differentiation

The immunoglobulin alpha (Ig alpha)/Ig beta heterodimer was detected on the surface of mu-negative proB cell lines in association with calnexin. The cross-linking of Ig beta on proB cells freshly isolated from bone marrow of recombination activating gene (RAG)-2-deficient mice induced a rapid and transient tyrosine-phosphorylation of Ig alpha as well as an array of intracellular proteins including Syk, PI3-kinase, Vav, and SLP-76. It also elicited the phosphorylation and activation of a MAP kinase ERK but not JNK/SAPK or p38. When RAG-2-deficient mice were treated with anti-Ig beta monoclonal antibody, developmentally arrested proB cells were induced to differentiate to the small preB cell stage as observed when the mu transgene was expressed in RAG-2-deficient mice. Thus, the cross-linking of Ig beta on proB cells appears to elicit differentiation signals analogous to those delivered by the preB cell receptor in normal B cell development.

Validity and reliability of Structured Interview for Competency Incompetency Assessment Testing and Ranking Inventory

The Structured Interview for Competency and Incompetency Assessment Testing and Ranking Inventory (SICIATRI) is a structured interview guide to assess the competency for giving informed consent to treatment among psychiatric and medical patients. The competency levels of 48 psychiatric and medical inpatients were assessed by SICIATRI. A relatively high- inter-rater reliability of the SICIATRI items (over half of the items had kappa > or = .60) and concurrent validity (sensitivity = .83, specificity = .67 as measured against the global judgement of competency rating by the attending physician) were obtained. In addition to its brevity (it takes about 20 minutes to complete), these findings may warrant application of this instrument in a clinical setting.

The roles of preB cell receptor in early B cell development and its signal transduction

The preB cell receptor is expressed for a short period after mu heavy chain is produced, that is, at the large preB cell stage in B cell development. The severe impairment of B cell differentiation observed in mice deficient for the preB cell receptor clearly demonstrated the importance of the preB cell receptor in B cell development. Analyses of bone marrow precursor B cells in normal and B cell-deficient mutant mice indicated the preB cell receptor transduced signals to drive cell cycle and to induce allelic exclusion. The proliferation of the preB cell receptor-expressing cells leads to the selective expansion of cells which have succeeded in the productive rearrangement of mu heavy chain gene. This process builds up a preB cell pool large enough to generate sufficient numbers of mature B cells. The preB cell receptor appears to induce allelic exclusion by shutting off the expression of recombinase activation gene (RAG). In order to analyse the signal transduction pathway downstream of the preB cell receptor, we have developed a new system in which cross-linking of Ig beta expressed on bone marrow proB cells mimics the signalling through the preB cell receptor to induce differentiation from proB to small preB cells.