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.     

Interference with viral infection by defective RNA replicase.

RNA-dependent RNA and DNA polymerases have a conserved segment, Tyr-X-Asp-Asp (G. Karmer and P. Argos, Nucleic Acids Res. 12:7269-7282, 1984). To investigate the function of this segment, we changed the Gly residue at position 357 in the conserved sequence Tyr-356-Gly-357-Asp-358-Asp-359 of the replicase of RNA coliphage Q beta to Ala, Ser, Pro, Met, or Val and examined the replicase activity in vivo. Cells carrying the variant plasmids lost the replicase activity and severely inhibited the proliferation of phage Q beta (group III) and related phage SP (group IV) by suppressing phage RNA synthesis. In contrast, substitution of the Gly residue at 390 showed only a slight inhibitory effect, although replicase activity was also lost. These results suggest that the cells harboring an altered replicase at the conserved segment can interfere specifically with the wild-type phage and different but related phage infections.     

Regional assignment of five genes on human chromosome 19

A human-mouse hybrid segregant HM76Dd40-6 with new characteristics was derived from the hybrid cell line HM76Dd containing human chromosome 19 as the only human chromosome. Three virus sensitivities located on human chromosome 19 (PVS, E11S and RDRC) were lost in HM76Dd40-6, while six other genes (C3, LDLR, EF2, GPI, PEPD and MANB) were retained. Cytogenetic analysis and in situ hybridization using human or mouse repeated sequences as probes showed that the region q13.1-qter of human chromosome 19 had been replaced by a fragment of mouse chromosome. Our results permit further regional assignment for the following five genes on human chromosome 19: GPI in the region cen-q12, MANB in p13.2-q12, E11S and RDRC in q13.1-qter, and EF2 in pter-q12.     

Antibody-dependent cell-mediated cytotoxicity using a murine monoclonal antibody against human colorectal cancer in cancer patients

Summary Antibody-dependent cell-mediated cytotoxicity (ADCC) mediated by a murine monoclonal antibody against human colerectal carcinoma, antibody 19–9, with human effector cells was tested in 33 patients with various carcinomas, 16 patients with benign lesions, and 13 normal controls, using a 12-h ⁵¹Cr release assay using human colorectal cancer cells as targets. Peripheral blood mononuclear cells (PBM) from these groups of patients and normal controls achieved moderate levels of target cell lysis in the presence of the monoclonal antibody at the high effector to target cell ratio of 200:1. The ADCC activity of PBM in cancer patients was significantly higher than that in either normal persons or patients with benign lesions. Since the ADCC was shown to be mainly mediated by adherent monocytes in the PBM, ADCC activity of monocytes from cancer patients was compared to those from control groups at an effector to target cell ratio of 30:1. The results also showed that the lytic capacity of monocytes was significantly higher in cancer patients than that in the control populations.     

N-Terminal Amino Acid Sequence and Processing Site of Sweet Potato Cytochrome c Oxidase Subunit II

The N-terminal amino acid sequence of sweet potato cytochromec oxidase subunit II polypeptide was determined. Comparisonsbetween the sequence and amino acid sequences deduced from thenucleotide sequences of other higher plant subunit II genesindicate a post-translational clevage of N-terminal extensionpart. ¹Present address: Institute of Low Temperature Science, HokkaidoUniversity, Sapporo, 060 Japan. (Received June 13, 1989; Accepted September 8, 1989)     

Fluorimetric coupled enzyme assay for lysoplasmalogenase activity in liver.

Two new proteins with apparent molecular masses of 53 kDa and 190 kDa have been identified in both sarcoplasmic reticulum and human blood platelets using a monoclonal antibody, FII1b5. The sarcoplasmic reticulum FII1b5 antigens were present in the terminal cisternae fraction, but were absent from light sarcoplasmic reticulum. The platelet and skeletal muscle proteins were not sensitive to digestion with endoglycosidase H under conditions that removed carbohydrate from the 53 kDa glycoprotein in sarcoplasmic reticulum or GPIIIa in platelet microsomes and did not bind 45Ca in a nitrocellulose overlay calcium-binding assay. These results distinguished the FII1b5 antigens from the 53 kDa glycoprotein and calsequestrin of sarcoplasmic reticulum. The 190 kDa platelet and sarcoplasmic reticulum proteins were extracted from membranes with high concentrations of NaCl, indicating that the high molecular mass FII1b5 antigens are peripherally associated with the bilayers. In contrast, the platelet and muscle 53 kDa proteins remained membrane-bound in the presence of high salt concentrations, suggesting that they are integral proteins.