Association between light exposure at night and manic symptoms in bipolar disorder: cross-sectional analysis of the APPLE cohort

ABSTRACT

Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a “hypomanic state.” The median (interquartile range) YMRS score was 2.0 (0–5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09–4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15–5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients.     

Characterization of Avian Paramyxoviruses Isolated from Feral Ducks in Northern Japan: The Presence of Three Distinct Viruses in Nature

Seventy-eight strains of avian paramyxoviruses (PMV) were isolated from cloacal and/or tracheal swabs taken from 1,342 feral ducks, comprised of spot-bill ducks, mallards, pintails, teals, falcated teals, wigeons and buffie-heads, in Wakuya-cho, Miyagi Prefecture, Japan, between 1976 and 1979. Five and a half percent of the ducks were positive for virus. Serological and structural characterization indicated that three different avian paramyxoviruses arc prevalent in the Japanese feral duck population. The first group of PMV was Newcastle disease virus (NDV), and in vivo pathogenecity tests in embryonated chicken eggs and 1-day-old chicks revealed that all the NDV strains isolated were avirulent. The second and most prevalent strain was closely related to PMV-4, duck/Hong Kong/D3/75 strain. The viruses of the third group were recovered only from pintails. They cross-reacted antigenically with PMV-3 when antisera to the PMV-3 reference strains, turkey/Wisconsin/68 and parakeet/Netherlands/449/75, were employed. However, no cross-reaction was observed when antiserum to pintail/ Wakuya/20/78, the prototype of this group, was used. The viruses of the third group also differed in viral polypeptide profile from the reference strains of PMV-3.     

Molecular cloning of a non-isopeptide-selective human endothelin receptor.

We isolated several complementary DNA (cDNA) clones encoding a non-isopeptide-selective human endothelin receptor (ETBR) from a human placenta cDNA library. The clones, different in the length of their 3'-untranslated regions, encoded the same 442-amino acid protein with a transmembrane topology similar to that of other G protein-coupled receptors. The rank order of the binding of ET isopeptides (ET-1, ET-2 and ET-3) to the receptor expressed in COS-7 cells was ET-1 = ET-2 = ET-3. Northern blot analysis identified three mRNA species, 4.3 kb, 2.7 kb and 1.7 kb in size, probably generated by their use of alternative polyadenylation sites. These mRNAs were expressed in a wide variety of human tissues, at the highest level in the brain and at a significant level in cultured endothelial cells.     

Capability of intensity discrimination in multiple receptor model of insect taste

A simple model in which one CNS taste neuron integrates inputsfrom multiple peripheral receptors is introduced in order toinvestigate the mechanism of acute intensity taste discriminationin flies. Information theory is applied to evaluate the acuteability of discrimination provided by the model. The presentanalysis is carried out under two statistical conditions concerningthe uncertainty of receptor response. Based on experimentaldata obtained by Smith et al. (1983), we estimate the mutualinformation entropy of the model. The numerical results obtainedhere indicate that the uncertainty observed in a single receptorresponse is dramatically reduced by the central integration.Furthermore, each of the eleven stimulus intensity levels experimentallyapplied by Smith et al., can be discriminated completely byintegrating the responses of the realistic number of receptors(33–212). Such a great improvement of the differentialsensitivity in the model resolves the discrepancy between thelow differential sensitivity of single sugar receptors (Smithet al., 1983) and the high sensitivity obtained in the feedingbehavior (Dethier and Rhoades, 1954; Dethier and Bowdan, 1984)of the blowfly.     

Identification and estimation algorithm for stochastic neural system. II

The algorithm for identifying the stochastic neural system and estimating the system process which reflects the dynamics of the neural network are presented in this papar. The analogous algorithm has been proposed in our preceding paper (Nakao et al., 1984), which was based on the randomly missed observations of a system process only. Since the previous algorithm mentioned above was subject to an unfavorable effect of consecutively missed observations, to reduce such an effect the algorithm proposed here is designed additionally to observe an intensity process in a neural spike train as the information for the estimation.The algorithm is constructed with the extended Kalman filters because it is naturally expected that a nonlinear and time variant structure is necessary for the filters to realize the observation of an intensity process by means of mapping from a system process to an intensity process. The performance of the algorithm is examined by applying it to some artificial neural systems and also to cat's visual nervous systems. The results in these applications are thought to prove the effectiveness of the algorithm proposed here and its superiority to the algorithm proposed previously.     

A case of Klinefelter's syndrome associated with hypothalamic-pituitary dysfunction caused by an intracranial germ cell tumor

A 17 year-old boy was admitted to the hospital because of thirst, polyuria (5-61/day), delayed sexual development and muscle weakness. He appeared obese, had an eunuchoidal body habitus and was excessively tall. Chromosomal analysis revealed a 47XXY karyotype. Serum cortisol was 1.3 microgram/dl, LH, 10.4 mIU/ml, FSH, 2.0 mIU/ml, and testosterone, 10 ng/dl. Endocrinological dynamic tests indicated diabetes insipidus and hypopituitarism of a hypothalamic type. Brain CT disclosed the existence of a tumor shadow around the calcified pineal body, extending towards the suprasellar region. Replacement therapy with glucocorticoid and DDAVP was started. The patient complained of a headache and plasma AFP and hCG concentrations were 868 ng/ml and 68.6 IU/ml respectively. A hCG- and AFP- producing germ cell tumor was suspected and radiation therapy with 60Co was performed. Plasma AFP and hCG were decreased with significant clinical improvement. Soon after irradiation, he started to complain of a headache and had elevated AFP and hCG levels. Right hemiparesis and unconsciousness suddenly appeared and he died of left thalamic bleeding. This is the first case of Klinefelter's syndrome associated with intracranial germ cell tumor. Plasma testosterone levels fluctuated in parallel with the change in plasma hCG levels. This shows that the Leydig cells in this patient could respond to some extent to tumor-producing hCG.     

Cancer Cell Analyses at the Single Cell-Level Using Electroactive Microwell Array Device

Circulating tumor cells (CTCs), shed from primary tumors and disseminated into peripheral blood, are playing a major role in metastasis. Even after isolation of CTCs from blood, the target cells are mixed with a population of other cell types. Here, we propose a new method for analyses of cell mixture at the single-cell level using a microfluidic device that contains arrayed electroactive microwells. Dielectrophoretic (DEP) force, induced by the electrodes patterned on the bottom surface of the microwells, allows efficient trapping and stable positioning of single cells for high-throughput biochemical analyses. We demonstrated that various on-chip analyses including immunostaining, viability/apoptosis assay and fluorescent in situ hybridization (FISH) at the single-cell level could be conducted just by applying specific reagents for each assay. Our simple method should greatly help discrimination and analysis of rare cancer cells among a population of blood cells.