Electroconvulsive seizures influence dendritic spine morphology and BDNF expression in a neuroendocrine model of depression.

BACKGROUND: Electroconvulsive therapy (ECT) is a rapid and effective treatment for major depressive disorder. Chronic stress-induced depression causes dendrite atrophy and deficiencies in brain-derived neurotrophic factor (BDNF), which are reversed by anti-depressant drugs. Electroconvulsive seizures (ECS), an animal model of ECT, robustly increase BDNF expression and stimulate dendritic outgrowth. OBJECTIVE: The present study aims to understand cellular and molecular plasticity mechanisms contributing to the efficacy of ECS following chronic stress-induced depression. METHODS: We quantify Bdnf transcript levels and dendritic spine density and morphology on cortical pyramidal neurons in mice exposed to vehicle or corticosterone and receiving either Sham or ECS treatment. RESULTS: ECS rescues corticosterone-induced defects in spine morphology and elevates Bdnf exon 1 and exon 4-containing transcripts in cortex. CONCLUSIONS: Dendritic spine remodeling and induction of activity-induced BDNF in the cortex represent important cellular and molecular plasticity mechanisms underlying the efficacy of ECS for treatment of chronic stress-induced depression.

Predictive factors for pericardial effusion identified by heart dose-volume histogram analysis in oesophageal cancer patients treated with chemoradiotherapy.

OBJECTIVE: To identify predictive factors for the development of pericardial effusion (PCE) in patients with oesophageal cancer treated with chemotherapy and radiotherapy (RT). METHODS: From March 2006 to November 2012, patients with oesophageal cancer treated with chemoradiotherapy (CRT) using the following criteria were evaluated: radiation dose >50 Gy; heart included in the radiation field; dose-volume histogram (DVH) data available for analysis; no previous thoracic surgery; and no PCE before treatment. The diagnosis of PCE was independently determined by two radiologists. Clinical factors, the percentage of heart volume receiving >5-60 Gy in increments of 5 Gy (V5-60, respectively), maximum heart dose and mean heart dose were analysed. RESULTS: A total of 143 patients with oesophageal cancer were reviewed retrospectively. The median follow-up by CT was 15 months (range, 2.1-72.6 months) after RT. PCE developed in 55 patients (38.5%) after RT, and the median time to develop PCE was 3.5 months (range, 0.2-9.9 months). On univariate analysis, DVH parameters except for V60 were significantly associated with the development of PCE (p < 0.001). No clinical factor was significantly related to the development of PCE. Recursive partitioning analysis including all DVH parameters as variables showed a V10 cut-off value of 72.8% to be the most influential factor. CONCLUSION: The present results showed that DVH parameters are strong independent predictive factors for the development of PCE in patients with oesophageal cancer treated with CRT. ADVANCES IN KNOWLEDGE: A heart dosage was associated with the development of PCE with radiation and without prophylactic nodal irradiation.

Threonine 74 of MOB1 is a putative key phosphorylation site by MST2 to form the scaffold to activate nuclear Dbf2-related kinase 1.

Mammalian nuclear Dbf2-related (NDR) kinases (LATS1 and 2, NDR1 and 2) play a role in cell proliferation, apoptosis and morphological changes. These kinases are regulated by mammalian sterile 20-like kinases (MSTs) and Mps one binder (MOB) 1. Okadaic acid (OA), which activates MST2, facilitates the complex formation of MOB1, MST2 and NDR1 in HEK293FT cells. The in vitro biochemical study demonstrates the phosphorylation of MOB1 by MST2. The phosphorylated MOB1 alone is capable to partially activate NDR1 in vitro, but MST2 is also required for the full activation. The knockdown of MOB1 or MST2 abolishes the OA-induced NDR1 activation in HEK293FT cells. Among MOB1 mutants, in which each serine or threonine residue is replaced with alanine, MOB1 T74A and T181A mutants fail to activate NDR1. Thr74, but not Thr181, is phosphorylated by MST2 in vitro, although MOB1 is also phosphorylated by MST2 at other site(s). The interaction of MOB1 T74A with NDR1 is barely enhanced by OA treatment. These findings indicate that the phosphorylation of MOB1 at Thr74 by MST2 is essential to make a complex of MOB1, MST2 and NDR1, and to fully activate NDR1.

Down-regulation of IL-12 p40 gene in Plasmodium berghei-infected mice.

We analyzed the mechanism that causes suppression of IL-12 p40 gene induction during Plasmodium berghei infection. Although IL-12 together with IFN-gamma plays an important role in protection against pathogenic infection, the IL-12 p70 protein production of infected macrophages is lower than that by the uninfected macrophages. We showed in the present study that the induction of IL-12 p40 gene but not IL-12 p35 gene in macrophages of P. berghei-infected mice was profoundly inhibited. The inhibition was induced by interaction with macrophages that had contacted with P. berghei-infected erythrocytes and was mediated by a soluble factor, IL-10. There was comparable activation of NF-kappaB in uninfected and infected cells. The induction of IFN-regulatory factor-1 gene was comparable in transcription level in uninfected and infected cells, while the unidentified complex formation of IFN-regulatory factor-1 was observed in infected cells. Therefore, the inhibition of the IL-12 p40 gene induction appeared to be regulated at transcriptional regulation level of the gene.

Localization of recombination activating gene 1/green fluorescent protein (RAG1/GFP) expression in secondary lymphoid organs after immunization with T-dependent antigens in rag1/gfp knockin mice.

Secondary rearrangements of immunoglobulin gene segments that generate a new antibody repertoire in peripheral B cells have been described as receptor revision and occur by as yet unknown mechanisms. To determine the importance of recombination activating gene (RAG) expression in receptor revision, heterozygous rag1/green fluorescent protein (gfp) knockin mice were used to examine the location of RAG1 expression in the germinal centers (GCs) of lymphoid follicles after immunization with a variety of T-cell-dependent antigens. Immunization of rag1/gfp heterozygous mice or rag1 homozygous knockout mice reconstituted with rag1/gfp heterozygous spleen cells caused the down-regulation of RAG1/GFP signal in GCs. Although some RAG1/GFP(+) cells appeared in regions surrounding the peanut agglutinin (PNA)(+)GL-7(+) GC area, RAG1/GFP(+) cells did not accumulate in the central region. In addition, the stimulation of spleen B cells with anti-mu antibody plus interleukin-4 (IL-4) or with anti-CD40 monoclonal antibody plus IL-7 did not induce GFP signals at detectable levels in vitro. These results clearly demonstrate that RAG1 re-expression either does not occur or is at extremely low levels in antigen-driven B cells in GCs of secondary lymphoid follicles, suggesting that other mechanisms may mediate the gene rearrangements observed in receptor revision.

CD40 expression is induced by the introduction of IgM receptor on the surface of pro-B cell line NFS70.

To examine the molecular mechanism of B cell differentiation, we introduced rearranged immunoglobulin (Ig) mu- and kappa-chain genes into the NFS70 pro-B cell line and observed their maturation. The IgR(+)-transfectants had characteristics of mature surface IgM (sIgM)+ B220high CD40+ CD38+ CD25+ B cells. CD40 expression levels were regulated by stimulation via the IgR. In comparison to wild type NFS70 cells, NF-kappaB activity was up-regulated in the IgR transfectants. Anti-IgR crosslinking of IgR+ cells induced down-regulation of CD40 expression that correlated with down-regulation of NF-kappaB activity in the IgR(+)-transfectants. Immature CD19+ sIgD- B cells from bone marrow also showed an alteration of CD40 expression in response to anti-IgR crosslinking. The results suggest that expression of IgR on the surface is one of the factors responsible for further maturation of B cells.

[Responses of electroencephalogram to different odors].

The responses of electroencephalogram (EEG) to different odors and their densities were studied on four men and two women at rest while sitting. The odors examined were citrus, floral and lavender, and their densities were 100 ppb and 200 ppb. The odors were released for ten minutes from a duct to fill the room completely. The subjective estimation indicated that citrus had a tendency to be the most comfortable odor in this study, but it was not significant. To evaluate changes of EEG, the power spectra of frequency-fluctuation of alpha wave (Fz) and the rate of alpha, beta, and beta/alpha wave (Oz, Fz) were calculated. The rate of alpha wave (Oz) in the period of giving out the citrus at 100 ppb was significantly (p < 0.05) higher than that of the lavender. The rate of beta wave (Oz) in the period of giving out the floral at 200 ppb was significantly (p < 0.05) higher than that of the lavender. The regression coefficient of the power spectra of frequency-fluctuation of alpha wave in the period of giving out the lavender at 100 ppb was significantly higher than those in the other periods of the experiment. The regression coefficient of the power spectra of frequency-fluctuation of alpha wave for lavender given out at 200 ppb was significantly (p < 0.01) higher than those for the other odors given out. It seems that the regression coefficient of the power spectra of frequency-fluctuation of alpha wave can be used for the evaluation of psychophysiological responses.

Isolation and characterization of a cDNA clone encoding the TATA box-binding protein (TFIID) from wheat.

We isolated a complementary DNA (cDNA) encoding the TATA-binding factor 'TFIID' from a wheat seedling cDNA library. The wheat TFIID transcript of 1.2 kb poly(A)+ RNA was expressed at a low level early in germination, but gradually increased as the seedlings developed. In vitro binding experiments showed that the bacterially expressed wheat TFIID protein could specifically bind to the TATA boxes of the cauliflower mosaic virus (CaMV) 35S, wheat histone H3 and adenovirus major late genes with different affinity. A comparison with Arabidopsis TFIID showed the presence of a plant-specific region consisting of 13 amino acids at the divergent amino terminus and a conserved region (182 amino acids) at the carboxy terminus longer than that observed in yeasts (180 amino acids) and animals (181 amino acids).

Sequences involved in brain-specific in vitro transcription from the core promoter of the mouse myelin basic protein gene.

In the previous study, we have shown that a short DNA stretch from -35 to -17 in the core promoter of the mouse myelin basic protein (MBP) gene is mainly responsible for brain-specificity in in vitro transcription. In this study, we found from intensive mutation analysis that the TATA-box sequence at -34 is not critical, but sequences downstream from the TATA-box especially around -20 were important for brain-specificity. The existence of a tissue-specific factor for the MBP core promoter different from the TATA-box-binding factor TFIID is implicated.

Striking homology of the 'variable' N-terminal as well as the 'conserved core' domains of the mouse and human TATA-factors (TFIID).

A complementary DNA (cDNA) encoding a mouse TFIID (mIID) was isolated from mouse brain cDNA libraries. The 316 amino acid sequence deduced from cDNA sequences revealed the presence of an amino-terminal region enriched in serine, threonine, and proline (STP-cluster), an uninterrupted stretch of 13 glutamine residues (Q-run), a second STP-cluster, and a conserved carboxy-terminal region. Amino acid sequences of the first STP-cluster and the conserved carboxy-terminal region were identical to those of the human TFIID (hIID). However, the Q-run was considerably shorter than that in hIID and sequences in the second STP-cluster diverged from those of the hIID. The murine TFIID transcript is expressed as a 2 kilobase poly(A)+ RNA in the mouse brain. Southern blot analysis identified a single gene copy per haploid mouse genome.

Core promoter of the mouse myelin basic protein gene governs brain-specific transcription in vitro.

The core promoter of the mouse myelin basic protein (MBP) gene from -36 to +12 was preferentially transcribed in brain nuclear extracts. Both the TATA at -34 and downstream elements to +12 were required for efficient, accurate and brain-specific transcription. From brain and liver nuclear extracts, we have partially purified the general transcription factor TFIID. The partially purified fractions contained TATA element binding factors of the MBP promoter as well as adenovirus major late promoter (MLP). The tissue-derived TFIID was functionally exchangeable for the HeLa TFIID, and directed transcription from the MLP. Surprisingly, the brain TFIID activated transcription from the MBP core promoter while the liver TFIID did to a much lesser extent. Exchange of the TATA-containing short DNA stretch to the MBP core promoter for a corresponding region of the mouse albumin promoter or MLP abolished the brain specificity. We found that several tissue-specific promoters other than MBP, such as mouse neurofilament and human alpha-1-antitrypsin promoters were also transcribed much more efficiently by the brain and liver TFIID, respectively. We suggest that different tissues contain functionally non-equivalent TFIID or TFIID-like activities.