Merkel Cells Release Glutamate Following Mechanical Stimulation: Implication of Glutamate in the Merkel Cell-Neurite Complex.

Merkel cells (MCs) have been proposed to form a part of the MC-neurite complex with sensory neurons through synaptic contact. However, the detailed mechanisms for intercellular communication between MCs and neurons have yet to be clarified. The present study examined the increases in intracellular free Ca concentration ([Ca]) induced by direct mechanical stimulation of MCs.

α-Amylase inhibitory triterpene from Abrus precatorius leaves.

In the screening experiments for porcine pancreatic α-amylase inhibitors in 18 plants obtained from Indonesia, a potent inhibitory activity was detected in the extract of leaves of Abrus precatorius. The enzyme assay-guided fractionation of the extract led to the isolation of a triterpene ketone, lupenone (1), as a potent α-amylase inhibitor, together with 24-methylenecycloartenone (2) and luteolin (3). The mode of inhibition of compound 1 against porcine pancreatic α-amylase was a mixed inhibition.

Odontoblasts as sensory receptors: transient receptor potential channels, pannexin-1, and ionotropic ATP receptors mediate intercellular odontoblast-neuron signal transduction.

Various stimuli induce pain when applied to the surface of exposed dentin. However, the mechanisms underlying dentinal pain remain unclear. We investigated intercellular signal transduction between odontoblasts and trigeminal ganglion (TG) neurons following direct mechanical stimulation of odontoblasts.

Functional expression of TRPM8 and TRPA1 channels in rat odontoblasts.

Odontoblasts produce dentin during development, throughout life, and in response to pathological conditions by sensing stimulation of exposed dentin. The functional properties and localization patterns of transient receptor potential (TRP) melastatin subfamily member 8 (TRPM8) and ankyrin subfamily member 1 (TRPA1) channels in odontoblasts remain to be clarified. We investigated the localization and the pharmacological, biophysical, and mechano-sensitive properties of TRPM8 and TRPA1 channels in rat odontoblasts.

[Construction of Maladaptive Behavior Scale in Japanese].

Objectives: To evaluate child development, social competence, like intellectual ability, is an important aspect. The social competence of a child is prescribed by behaviors suitable for the society (adaptive behaviors) and behaviors not suitable for the society (maladaptive behaviors). The Vineland Adaptive Behavior Scales (VABS) have been widely administered to children in a semi-structural interview to evaluate social competence.

Neurobehavioral effects of prenatal exposure to methylmercury and PCBs, and seafood intake: neonatal behavioral assessment scale results of Tohoku study of child development.

As factors affecting neonatal neurodevelopment, methylmercury, polychlorinated biphenyls (PCBs), and maternal seafood intake reflecting n-3 polyunsaturated fatty acids (PUFAs) are believed to have adverse or beneficial effects, but there are a few reports addressing such factors simultaneously. We carried out a birth cohort study to clarify the effects of these three factors on the Neonatal Behavioral Assessment Scale (NBAS), administered 3 days after birth. In a total of 498 mother-neonate pairs, the total mercury level (median, 1.

Gene expression profiles in the brain of the neonate mouse perinatally exposed to methylmercury and/or polychlorinated biphenyls.

Methylmercury (MeHg) and polychlorinated biphenyls (PCBs) are environmentally persistent neurodevelopmental toxicants. The primary source of human exposure is the consumption of contaminated fish, seafood and marine mammals. However, little is known about the molecular mechanisms of MeHg and PCB toxicities and interactions between these contaminants.

Intervention study on cardiac autonomic nervous effects of methylmercury from seafood.

To scrutinize whether the provisional tolerable weekly intake (PTWI, 3.4 microg/kg body weight/week) of methylmercury in Japan is safe for adults, we conducted an intervention study using heart rate variability (HRV) that has been considered to reflect cardiac events. Fifty-four healthy volunteers were recruited and divided into experimental and control groups.

Assessment of exposure to methylmercury in pregnant Japanese women by FFQ.

Objective: To examine whether an FFQ can be used for assessing exposure to methylmercury (MeHg) by estimating MeHg intake from seafood consumption using the FFQ and confirming the accuracy of the estimated value.

Design: Seafood consumption of pregnant women was assessed using the FFQ. Total mercury (T-Hg) concentrations of maternal red blood cells (RBC) and hair were measured as exposure indices of MeHg.

Trends of body mass index distribution in schoolchildren in Sendai, Japan, 1989-2003.

Accumulating evidence indicates a strong association between obesity and health problems. Childhood obesity increases the risk of adulthood obesity. Although it is reported that the number of obese children in Japan has increased, it is unclear whether the obesity index distribution pattern has changed.

Trends in growth status among schoolchildren in Sendai, Japan, 1994-2003: leveling-off of mean body height and weight.

Secular changes in growth have been well documented in various world populations, with secular increase especially noticeable in the developed countries. Accordingly, we have been monitoring the secular changes in growth status among the 6th year children in primary schools (6thPS, 11-12 years old) and 3rd year children in junior high schools (3rdJHS, 14-15 years old) in the city of Sendai since 1934. After World War II, both primary school children and junior high school students showed marked increases in height and weight up to the early 1970s.

Permanent waving does not change mercury concentration in the proximal segment of hair close to scalp.

Mercury in hair is a generally accepted biomarker of methylmercury exposure, and permanent waving has been reported to affect the mercury concentration in hair. We conducted an experimental-field study to examine the changes in the mercury concentration in hair induced by treatments such as permanent waving, straightening and coloring. Hair samples were collected from 19 female subjects enrolled before and after hair treatment by a beautician during each visit to a beauty saloon.

Effects of perinatal coexposure to methylmercury and polychlorinated biphenyls on neurobehavioral development in mice.

Methylmercury (MeHg) and polychlorinated biphenyls (PCBs) are environmental pollutants that cause neurobehavioral deficits in humans. Because exposures to MeHg and PCBs occur through fish consumption, it is necessary to clarify the effects of the interaction of the two pollutants. Therefore, we investigated the effects of perinatal exposure to MeHg and PCBs on the neurobehavioral development in mice.

Assessment of intrauterine methylmercury exposure affecting child development: messages from the newborn.

In evaluating the health effects in the offspring born to the mothers exposed to methylmercury (MeHg) during pregnancy, biomarkers obtained from maternal blood and hair, and umbilical cord have been employed for the exposure assessment. However, which biomarker is employed may affect the study conclusion. In this sense, umbilical cord mercury concentration appears to be a direct exposure biomarker of the fetus.

[Usefulness of umbilical cord mercury concentrations as biomarkers of fetal exposure to methylmercury].

In epidemiological studies on the health effect of methylmercury (MeHg) exposure, maternal-hair mercury concentration has been used as an exposure biomarker because of its ease of collection and capability to recapture the exposure history. However, artificial hair-waving reduces the mercury concentration and there is little agreement about which part of the hair strand properly represents fetal exposure. We presented an overview of the studies addressing umbilical cord and mercury in PubMed and evaluated the usefulness of umbilical cord mercury concentrations as biomarkers of fetal exposure to MeHg.

LARK activates posttranscriptional expression of an essential mammalian clock protein, PERIOD1.

The mammalian molecular clock is composed of feedback loops to keep circadian 24-h rhythms. Although much focus has been on transcriptional regulation, it is clear that posttranscriptional controls also play important roles in molecular circadian clocks. In this study, we found that mouse LARK (mLARK), an RNA binding protein, activates the posttranscriptional expression of the mouse Period1 (mPer1) mRNA.