Lithium in drinking water and suicide prevention: The largest nationwide epidemiological study from Japan.

OBJECTIVES: The aims of the present study thus were (a) to further investigate the association between lithium levels in drinking water and suicide rates by adjusting relevant factors using the so far largest available dataset in Japan, (b) to confirm sex differences, (c) to estimate the effects of long-term exposure to trace lithium, (d) to investigate the effects of drinking bottled instead of tap water, and (e) to exploratorily investigate which lithium levels may be associated with lower suicide rates. METHODS: Mean lithium levels in drinking water of all 808 cities and wards (ie, 785 cities of 46 prefectures and 23 wards of Tokyo) in Japan were examined in relation to mean suicide standardized mortality ratios (SMRs) during the 7 years from 2010 to 2016. Multiple regression analyses adjusted for the size of each population were used to investigate the association of lithium levels with suicide SMRs with adjustments for relevant factors. RESULTS: The adjusted model showed significant inverse associations of lithium levels with total and male SMRs, but not with female SMRs. Neither the proportion of residents who continued to live in the same city nor the consumption of bottled water changed the association between lithium levels and suicide SMRs. Finally, it was 30 µg/L or more that was associated with lower suicide SMRs. CONCLUSIONS: The present findings reconfirm the inverse association between lithium levels in drinking water and suicide rates particularly in the male population.

Thought Process Evolved From Rigid to Flexible in a Patient With Bipolar Disorder Via "Return to Work Program": A Case Report.

ABSTRACT: In the working population, bipolar disorder can have a significant negative effect on professional relationships, attendance, functioning, and loss of productivity. In Japan, workers who take a leave due to depressive episodes receive a work-focused intervention program called the "return to work program" during their leave. A 39-year-old Japanese woman with bipolar II disorder took a third sick leave of absence. We recommended her the return to work program of our university hospital. At the beginning of the program, she had a rigid thought process toward her perceptions of her duties in the workplace and at home. Through the program, mindfulness might identify rigidity, group cognitive-behavioral therapy might correct rigidity, and self-analysis might have regained flexibility. In conclusion, a variety of effects of our return to work program might have enabled her thought process to evolve from rigid to flexible, and she showed successful reinstatement.

A specific group of patients with diagnostic conversion from depression to bipolar disorder and finally to dementia as a mental GSK-3 disease: A hypothesis.

OBJECTIVES: To focus on a specific group of patients whose diagnoses were changed from unipolar depression to bipolar disorder, and finally to dementia. METHODS: Qualitative review of the relevant articles. RESULTS: A substantial portion of patients with unipolar depression manifest manic and/or hypomanic episodes, resulting in a change of diagnoses to bipolar disorder. Further, a substantial portion of bipolar patients develop dementia. Previous research suggests that genetic variants in the glycogen synthase kinase 3ß (GSK-3ß) gene are associated with early onset of unipolar depression, a subset of which may be bipolar depression, with three SNPs (rs334555, rs119258668, and rs11927974) identified. Notably, another promotor SNP (rs334558) of the GSK-3ß gene is reportedly associated with unipolar depression, bipolar disorders, and dementia. Additionally, lithium, which is reported to inhibit GSK-3, is generally accepted to be effective for bipolar disorder and recently reported to be effective for dementia. CONCLUSIONS: There is a specific group of patients whose diagnoses longitudinally change from depression to bipolar disorder and finally to dementia, and GSK-3 may be a common etiological factor in these diseases and in diagnostic conversions.

Association between lithium in tap water and suicide mortality rates in Miyazaki Prefecture.

BACKGROUND: Most studies have reported that suicide mortality rates are negatively associated with lithium levels in tap water; however, a few studies showed either no association or a positive association. Thus, the association between suicide mortality and lithium levels in tap water remains controversial. To clarify the association, our study evaluated the association between lithium levels in tap water and suicide mortality rates in Miyazaki Prefecture of Japan, after adjusting for confounding factors. METHODS: We measured lithium levels in tap water across the 26 municipalities of Miyazaki Prefecture in Japan. We examined the standardized mortality ratio (SMR) for suicide in each municipality and used the data as the average suicide SMRs over 5 years (2009-2013). Weighted least-squares regression analysis, adjusted for the size of each municipality's population, was used to investigate the association between lithium levels in tap water and suicide SMRs. In addition to a crude model, in an adjusted model, potential confounding factors (proportion of elderly people, proportion of one-person households, annual marriage rate, annual mean income, unemployment rate, the density of medical doctors per 100,000 people, annual total rainfall, and proportion of people with a college education or higher) were added as covariates. RESULTS: We showed that male and female suicide SMRs were not associated with lithium levels in tap water in Miyazaki Prefecture. After adjusting for confounders, male suicide SMRs were significantly and positively associated with the proportion of elderly people in the population and annual total rainfall, and female suicide SMRs were associated with the proportion of elderly people in the population. CONCLUSIONS: No association between lithium levels in tap water and suicide mortality rates was found in Miyazaki Prefecture.

Relationship between hyperthymic temperament, self-directedness, and self-transcendence in medical students and staff members.

AIM: We aimed to investigate the hypotheses that hyperthymic temperament may be positively associated with self-directedness and self-transcendence with adjustment for relevant factors. METHODS: Using the database of our previous studies, the data from 111 healthy subjects with scores for both the Temperament and Character Inventory and the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire were secondarily used for the present study. RESULTS: Hyperthymic Temperament scores were significantly and positively associated with Self-Transcendence scores, but not with Self-Directedness scores, following adjustment for relevant factors. Despite the lack of association between self-transcendence and self-directedness, cooperativeness was significantly and positively associated with self-transcendence and self-directedness, but not with hyperthymic temperament. Moreover, despite the lack of association between hyperthymic temperament and self-directedness, harm avoidance was significantly and negatively associated with hyperthymic temperament and self-directedness, but not with self-transcendence. CONCLUSION: The present findings suggest that hyperthymic temperament may be positively associated with self-transcendence, but not with self-directedness. Moreover, hyperthymic temperament may be, a selfish and reckless trait, self-transcendence may be altruistic and not reckless, and self-directedness may be altruistic but reckless.

Relationship between ambient light and glucose metabolism in healthy subjects.

BACKGROUND: Given the reported inverse association between light and depressive mood, ambient light may also be associated with some of the brain regions in healthy subjects. The present study aims to investigate the effects of ambient light on glucose metabolism in the brain. We used the data of 28 healthy participants of the no intervention group from our previous randomized controlled trial and analyzed the association between ambient light and [18F]-FDG uptake in the brain. RESULTS: A whole brain analysis revealed a cluster of [18F]-FDG uptake that was significantly and inversely associated with log-transformed ambient light in the left culmen of the left cerebellum vermis. After adjustment for age, gender and serum melatonin levels, there remained a significant cluster of [18F]-FDG uptake with log-transformed ambient light in the left cerebellar vermis. CONCLUSIONS: The present findings suggest that the uptake of [18F]-FDG is significantly and inversely associated with ambient light in the left cerebellar vermis in healthy subjects. The cerebellar vermis may be involved in mood suppression which may be alleviated by light exposure where glucose uptake and metabolism in this area are decreased. Trial Registration This study is a secondary analysis of the previous randomized study which was registered as UMIN000007537. Retrospectively registered (March 20th, 2012).

Trace lithium and mental health.

Lithium therapy is generally accepted as a first-line treatment for bipolar disorder, and it is also identified as one of the best augmenting options for treatment-resistant depression. Furthermore, lithium has been investigated in association with suicide, dementia and aggressiveness. In this review, we examined articles about the effects of very small amounts of lithium in treating suicide, dementia, bipolar disorder and temperament, to assess the present state of trace lithium's effect on mental state. The results indicate that trace lithium may be effective for suicide prevention but randomized, placebo-controlled trials are required to draw a definite conclusion. Indications for using trace lithium in treating such conditions as dementia, bipolar disorder and temperament are supported by very limited evidence and such effects are yet to be determined.

Relationship between anxious temperament and harm avoidance in medical students and staff.

AIM: In order to resolve the equivocal relationship between anxious temperament rated by the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire (TEMPS-A) and harm avoidance rated by the Temperament and Character Inventory (TCI), the present study aimed to investigate whether the anxious temperament scale and the harm avoidance scale are significantly associated with adjustment of relevant factors. Our hypothesis was that anxious temperament might be associated with harm avoidance. METHODS: From the database of our previous studies, the data of 111 healthy subjects who had both TCI and TEMPS-A scores were extracted for the present study. Two multiple regression analyses were performed: one to predict variance in anxious temperament scores without and with harm avoidance scores, and relevant factors; and another to predict variance in harm avoidance scores without and with anxious temperament scores, and relevant factors. RESULTS: Anxious temperament was significantly and positively associated with depressive temperament, irritable temperament, and Hamilton Rating Scale for Depression whereas harm avoidance was significantly and negatively associated with hyperthymic temperament, novelty seeking, persistence, and self-directedness, although both were significantly and positively associated with each other. CONCLUSION: These findings support our hypothesis and suggest that anxious temperament may have 'depressive proneness' whereas harm avoidance may have 'passive proneness.'

Effects of indoor and outdoor cultivation conditions on 137 Cs concentrations in cultivated mushrooms produced after the Fukushima Daiichi Nuclear Power Plant accident.

BACKGROUND: Radiocesium (134 Cs and 137 Cs) in mushrooms has been a matter of public concern after the accident at Fukushima Daiichi Nuclear Power Plant. To minimize the internal dose by ingestion of cultivated mushrooms, the Japanese government set a guideline level with respect to the radiocesium concentration in bed-logs and mushroom beds; however, the effects of indoor and outdoor cultivation methods on radiocesium concentrations in cultivated mushrooms were not clear. RESULTS: The effects of indoor and outdoor cultivation on the radiocesium concentrations in mushroom were examined using published food monitoring data. 137 Cs concentration data in Lentinula edodes from the Aizu area in Fukushima Prefecture and seven prefectures outside Fukushima were used for the analysis. No statistically significant 137 Cs concentration differences were found between these two cultivation methods. Using detected 137 Cs data in shiitake, the geometric means from each prefecture were less than one-quarter of the standard limit (100 Bq kg-1 ) for total radiocesium under both cultivation conditions. CONCLUSION: It was suspected that re-suspended radiocesium might have been taken up by mushrooms or that radiocesium might have been absorbed into the mushrooms from the soil in the outdoor cultures. However, neither effect was significant for cultivated mushrooms in the areas examined. © 2016 Society of Chemical Industry.

Determination of ¹³5Cs and ¹³5Cs/¹³7Cs atomic ratio in environmental samples by combining ammonium molybdophosphate (AMP)-selective Cs adsorption and ion-exchange chromatographic separation to triple-quadrupole inductively coupled plasma-mass spectrometry.

Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011, the activity ratio of (134)Cs/(137)Cs has been widely used as a tracer for contamination source identification. However, because of the short half-life of (134)Cs (2.06 y), this tracer will become unavailable in the near future. This article presents an analytical method for the determination of the long-lived (135)Cs (t(2/1) = 2 × 10(6) y) and the atomic ratio of (135)Cs/(137)Cs, as a promising geochemical tracer, in environmental samples. The analytical method involves ammonium molybdophosphate (AMP)-selective adsorption of Cs and subsequent two-stage ion-exchange chromatographic separation, followed by detection of isolated radiocesium isotopes via triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-MS/MS). The AMP-selective adsorption of Cs and the chromatographic separation system showed high decontamination factors (10(4)-10(5)) for interfering elements, such as Ba, Mo, Sb, and Sn. Using ICP-MS/MS, only selected ions enter the collision/reaction cell to react with N2O, reducing the isobaric interferences ((135)Ba(+) and (137)Ba(+)) and polyatomic interferences ((95) Mo(40)Ar(+), (97) Mo(40)Ar(+), (119)Sn(16)O(+), and (121)Sb(16)O(+)) produced by sample matrix ions. The high abundance sensitivity (10(-9) for the (135)Cs/(133)Cs ratio) provided by ICP-MS/MS allowed reliable analysis of (135)Cs and (137)Cs isotopes with the lowest detection limits ever reported by mass counting methods (0.01 pg mL(-1) and 0.006 pg mL(-1), respectively). The developed analytical method was successfully applied to the determination of (135)Cs and (137)Cs isotopes in environmental samples (soil, litter, and lichen) collected after the FDNPP accident for contamination source identification.

Estimation of Te-132 distribution in Fukushima Prefecture at the early stage of the Fukushima Daiichi Nuclear Power Plant reactor failures.

Tellurium-132 ((132)Te, half-life: 3.2 d) has been assessed as the radionuclide with the third largest release from the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011; thus it would have made some dose contribution during the early stage of the reactor failures. The available data for (132)Te are, however, limited. In this study, available reported values of other isotopes of Te were compiled to estimate (132)Te concentration (in MBq m(-2)). It was found that (132)Te and (129m)Te (half-life: 33.6 d) concentrations were well correlated (R = 0.99, p < 0.001) by t test. Thus, (132)Te concentrations on March 11, 2011 were estimated from (129m)Te using the concentration conversion factor ((132)Te /(129m)Te) of 14.5. It was also found that since deposited (129m)Te was well retained in the soil, the data collected in March-May of 2011 were applicable to (132)Te estimation. It was possible to obtain the first (132)Te concentration contour map for the eastern part of Fukushima Prefecture, including data from within the 20-km exclusion zone around the FDNPP, using these newly available estimated (132)Te data sets.

Community structure of planktonic fungi and the impact of parasitic chytrids on phytoplankton in Lake Inba, Japan.

Freshwater fungi have received little attention by scientific research in recent years, especially fungi of the pelagic zone. Recently, parasitic fungi, termed chytrids, have been found to play important roles in aquatic food webs. Yet, the diversity and community structure of planktonic fungi including chytrids are not well studied. In this study, we examined the temporal fluctuations of freshwater fungi, including chytrids, in Lake Inba by using molecular techniques of denaturing gradient gel electrophoresis (DGGE). DGGE profiles, and associated sequence analysis, indicated that chytrids were present on all sampling dates from May to October (n = 12). In addition, analysis showed that a large proportion of the sequences belonged to chytrids of both parasitic and saprotrophic species. This finding was supported by microscopic observations using Calcofluor white to stain chytrids infecting various phytoplankton species. The percentages of infection by chytrids on two dominant diatom species, Aulacoseira granulata and Aulacoseira ambigua, showed a similar seasonal pattern in the DGGE band profiles. From the phylogenetic analysis and microscopic identification, the chytrids infecting the two diatoms are likely to be affiliated to Chytriomyces sp. and Zygorhizidium sp.. This is the first study to show that DGGE is a useful preliminary approach for examining the diversity of planktonic fungi including chytrids. Our results indicate both parasitic and saprotrophic chytrids are a significant component of freshwater fungi inhabiting the pelagic zone of Lake Inba, Japan. Further modification of DGGE, together with new molecular techniques and microscopic observation, would reveal the hidden diversity and ecological significance of planktonic fungi in aquatic ecosystems.