Aqueous mechano-bactericidal action of acicular aragonite crystals.

Nanoneedle structures on dragonfly and cicada wing surfaces or black silicon nanoneedles demonstrate antibacterial phenomena, namely mechano-bactericidal action. These air-exposed, mechano-bactericidal surfaces serve to destroy adherent bacteria, but their bactericidal action in the water is no precedent to report. Calcium carbonate easily accumulates on solid surfaces during long-term exposure to hard water. We expect that aragonite nanoneedles, in particular, which grow on TiO2 during the photocatalytic treatment of calcium-rich groundwater, exhibit mechano-bactericidal action against bacteria in water. Here, we showed that acicular aragonite modified on TiO2 ceramics prepared from calcium bicarbonate in mineral water by photocatalysis exhibits mechanical bactericidal activity against E. coli in water. Unmodified, calcite-modified and aragonite-modified TiO2 ceramics were exposed to water containing E. coli (in a petri dish), and their bactericidal action over time was investigated under static and agitated conditions. The surfaces of the materials were observed by scanning electron microscopy, and the live/dead bacterial cells were observed by confocal laser scanning microscopy. As a result, the synergistic bactericidal performance achieved by mechano-bactericidal action and photocatalysis was demonstrated. Aragonite itself has a high biological affinity for the human body different from the other whisker-sharpen nanomaterials, therefore, the mechano-bactericidal action of acicular aragonite in water is expected to inform the development of safe water purification systems for use in developing countries.

Clinical manifestations of liver injury in patients with anorexia nervosa.

AIM: The number of Japanese patients with anorexia nervosa (AN) is increasing as society changes. Mild liver injury is a complication of AN in around 30% of cases. In some rare instances, patients present with severe liver injury similar to acute liver failure. However, there are numerous uncertainties over the clinical characteristics of this condition. The objective of the present study was to clarify the clinical characteristics of AN complicated by liver injury and to investigate the factors related to hepatic complications. METHODS: Thirty-seven patients hospitalized at our institution with a diagnosis of AN were enrolled as the study subjects. The study used clinical data obtained at the time of hospitalization. The enrolled patients underwent subgroup analysis and were categorized into three groups: (i) normal alanine aminotransferase (ALT), (ii) moderately elevated ALT, and (iii) highly elevated ALT. RESULTS: All of the study subjects were female with a median age of 24 years and presenting with marked weight loss (mean body mass index, 13 kg/m(2) ). Thirteen of the subjects had liver injury. We found that patients in the highly elevated ALT group had a significantly high blood urea nitrogen (BUN)/creatinine ratio, and a low blood sugar level. CONCLUSIONS: Our present findings indicate that AN patients with highly elevated ALT have a severe dehydration. This suggests that dysfunction of hepatic circulation accompanying severe dehydration due to malnutrition may be an important factor in the development of liver injury in AN patients.

Effects of the "affectionless control" parenting style on personality traits in healthy subjects.

The effects of the affectionless control (AC) parenting style on personality traits were studied in 414 Japanese healthy subjects. Perceived parental rearing was assessed by the Parental Bonding Instrument, which comprises care and protection factors, and personality traits were assessed by the Temperament and Character Inventory, which has seven dimensions. Parental rearing was classified into four types, i.e., optimal parenting (high care/low protection), affectionate constraint (high care/high protection), neglectful parenting (low care/low protection), and AC (low care/high protection). Males with maternal AC showed significantly higher harm avoidance (HA) scores and lower scores of persistence and cooperativeness than those with maternal optimal parenting. Females with maternal AC showed significantly higher HA scores and lower self-directedness scores than those with maternal optimal parenting. Paternal AC was not significantly related to any personality score. In females, the interaction between paternal rearing and maternal rearing was significant; the effect of maternal AC on HA scores was strongest when combined with paternal neglectful parenting. The present study suggests that the AC type parenting by mothers is associated with specific personality traits, especially high HA, in healthy subjects.

Relationship of interpersonal sensitivity with dimensions of the Temperament and Character Inventory in healthy subjects.

The relationship of interpersonal sensitivity measured by the Interpersonal Sensitivity Measure (IPSM) with the 7 dimensions of the Temperament and Character Inventory (TCI) was studied in 481 healthy subjects. The multiple regression analysis showed that the IPSM scores were correlated with the scores of 5 dimensions of the TCI, and the correlations were especially strong with self-directedness (beta = -.35) and harm avoidance (beta = .29). In the principal component analysis of the IPSM combined with the TCI dimensions, the IPSM formed a group with self-directedness and harm avoidance, with respective loading values of 0.82, -0.83, and 0.69. The present study suggests that interpersonal sensitivity is related to some dimensions of the TCI, especially with low self-directedness and high harm avoidance.

The -181 A/C polymorphism in the excitatory amino acid transporter-2 gene promoter affects the personality trait of reward dependence in healthy subjects.

There have been some animal and human data suggesting that excitatory amino acid transporter (EAAT)-2, the major subtype of EAAT, is involved in human mental function and behavior. Recently, it has been shown that the -181 A/C polymorphism in the EAAT2 gene promoter affects plasma glutamate concentrations in humans. In the present study, the association of this genetic polymorphism with personality traits was examined in 575 Japanese healthy volunteers. Personality traits were assessed by the Temperament and Character Inventory, and the EAAT2 polymorphism was detected by a PCR-RFLP method. The scores of reward dependence were significantly (p=0.017) lower in the group with the A allele (A/A and A/C) than in that without this allele (C/C). When males and females were analyzed separately, the significant difference between the two genotype groups was observed in females (p=0.021) but not in males. The present study thus suggests that the -181 A/C polymorphism in the EAAT2 gene promoter affects the personality trait of reward dependence in healthy subjects.

Association study of catechol-O-methyltransferase Val158Met polymorphism with personality traits in Japanese healthy volunteers.

Catechol-O-methyltransferase (COMT) is one of the major enzymes for the degradation of catecholamines. It has been suggested that catecholaminergic neurotransmission is involved in characterization of personality. Previous studies on the association between the COMT Val158Met polymorphism and personality traits in healthy subjects have produced inconsistent results. Therefore, the relationship between this polymorphism and personality was re-examined in 478 Japanese healthy volunteers. Personality traits were assessed by the Temperament and Character Inventory (TCI), and the COMT genotypes were determined by a PCR-RFLP method. In total, there were no significant differences among the Val/Val, Val/Met, and Met/Met genotypes in seven TCI dimension scores. Similarly, no significant relationship was found between the COMT genotypes and the TCI dimensions when males and females were analyzed separately. The present study thus suggests that the COMT Val158Met polymorphism is not associated with personality traits in Japanese healthy subjects.

No association between the -3081A/T polymorphism in the norepinephrine transporter gene promoter and personality traits in healthy subjects.

There have been several data suggesting that norepinephrine neurotransmission is involved in the characterization of personality traits. Recently, the -3081A/T polymorphism in the promoter region of the norepinephrine transporter (NET) gene affecting promoter activity has been reported. In the present study, we studied the association between this NET polymorphism and personality traits in 553 Japanese healthy subjects. Personality traits were assessed by the Temperament and Character Inventory (TCI), and the NET genotypes were identified by a PCR-RFLP method. Multivariate two-factor analysis of covariance with genotype and gender as factors and with age as a covariate showed no association between the NET genotypes and the TCI dimension scores. The present study thus suggests that the -3081A/T polymorphism in the NET gene promoter is not involved in the characterization of personality traits in healthy subjects.

Influences of parental rearing on the personality traits of healthy Japanese.

Influences of parental rearing on the personality traits of healthy subjects were studied in 323 Japanese volunteers. Perceived parental rearing was assessed with the use of the Parental Bonding Instrument, which consists of the factors of care and protection, whereas personality traits were assessed with the use of the Temperament and Character Inventory, which has 7 dimensions. In male subjects, all personality dimensions except for novelty seeking were influenced by parental rearing; in female subjects, only the harm avoidance (HA) and self-directedness (SD) dimensions were affected by parenting. Paternal rearing influenced 3 dimensions in male subjects and 1 dimension in female subjects, whereas maternal rearing influenced 5 dimensions in male subjects and 2 dimensions in female subjects. In male subjects, higher HA was related to higher paternal protection (P < .05), whereas in female subjects, it was related to higher maternal protection (P < .01). In male subjects, lower SD was related to higher paternal protection (P < .05) and lower maternal care (P < .01), whereas in female subjects, it was related to lower paternal care (P < .05) and higher maternal protection (P < .01). These results suggest that parental rearing influences the personality traits of healthy subjects, especially HA and SD, with sex specificity in parents and recipients.

CYP2C19 polymorphism affects personality traits of Japanese females.

It has been suggested that personality traits are heritable. The polymorphic cytochrome P450 (CYP) 2C19 metabolizes sex hormones and 5-hydroxytryptamine, which are involved in multiple brain functions. In the present study, the relationship between the CYP2C19 polymorphism and personality traits was examined in 487 Japanese healthy volunteers. Personality traits were assessed by the Temperament and Character Inventory (TCI), and the two mutated alleles causing absent CYP2C19 activity were identified by a PCR-RFLP method. In females, the scores of reward dependence (p=0.026), cooperativeness (p=0.001), and self-transcendence (ST) (p=0.049) were significantly lower in poor metabolizers (PMs) than in extensive metabolizers (EMs). In males, none of the seven TCI dimensions was significantly different between EMs and PMs. The present study thus suggests that the CYP2C19 polymorphism affects personality traits of Japanese females.

No association between the TPH A218C polymorphism and personality traits in Japanese healthy subjects.

It has been suggested that the central serotonergic activity is implicated in personality traits. Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in serotonin synthesis. In the present study, the association between the TPH A218C polymorphism and personality traits assessed by the Temperament and Character Inventory (TCI) was examined in 345 Japanese healthy subjects. The TPH A218C polymorphism was determined by a PCR-RFLP method. There were no significant differences in the seven dimension scores of TCI among the A/A, A/C, and C/C genotype groups by the one-way ANOVA. There was a significant negative correlation between age and the NS scores. Females showed significantly higher scores of HA, RD, and ST, and significantly lower scores of SD than males. The multiple regression analysis using age, gender, and the TPH genotype as independent variables also showed no significant association between any dimension score and the genotype. The present study thus suggests that the TPH A218C polymorphism does not affect personality traits in Japanese healthy subjects.

Effects of caffeine on the kinetics of fluvoxamine and its major metabolite in plasma after a single oral dose of the drug.

The effects of caffeine on the kinetics of fluvoxamine (FLV) and its major metabolite fluvoxamino acid (FLA) in plasma, after a single oral dose of the drug, were studied in 12 healthy male volunteers. The subjects received caffeine 300 mg/d or placebo for 11 days in a double-blind randomized crossover manner, and on the eighth day they received a single oral 50-mg dose of FLV. Blood sampling and pharmacodynamic evaluation were conducted up to 72 hours after FLV dosing. Plasma concentrations of FLV and FLA were measured by high-performance liquid chromatography. Caffeine significantly decreased the plasma concentrations at 6 time points (P<0.05) and total area under the plasma concentration-time curve (156.5+/-51.7 vs. 118.9+/-38.2 ng/h/mL, P<0.01) of FLV. Plasma concentration and pharmacokinetic parameters of FLA were not affected by caffeine. Caffeine induced no significant change in the pharmacodynamic effects of FLV. The present study suggests that caffeine slightly induces the metabolism of FLV, probably mediated by CYP1A2.

Monoamine oxidase A gene promoter polymorphism affects novelty seeking and reward dependence in healthy study participants.

It has been suggested that monoamine oxidase A plays an important role in the characterization of personality. Previous studies on the association between the polymorphism of variable number tandem repeat in the promoter region of the monoamine oxidase A gene and personality traits have, however, been unproductive. In the present study, the association between the monoamine oxidase A variable number tandem repeat polymorphism and personality traits assessed by the Temperament and Character Inventory was examined in 324 Japanese volunteers without psychiatric disorders. The low activity allele with three repeats (allele 3) and high activity allele with four repeats (allele 4) were determined by a polymerase chain reaction method. The carriers of allele 3 in males and the homozygotes of allele 3 in females were classified as the low activity group, the heterozygotes of alleles 3 and 4 in females as the medium activity group, and the carriers of allele 4 in males and the homozygotes of allele 4 in females as the high activity group. One-way analysis of variance showed that the scores of novelty seeking (P=0.006) and reward dependence (P=0.013) were significantly higher in the high activity group than in the low activity group. Multiple regression analysis demonstrated that the excess in the high activity allele was significantly associated with higher scores of novelty seeking (P=0.004) and reward dependence (P=0.003). The present study thus suggests that the monoamine oxidase A variable number tandem repeat polymorphism affects novelty seeking and reward dependence in healthy study participants.