11 research outputs found
Neutron Majorana mass from exotic instantons
We show how a Majorana mass for the Neutron could result from
non-perturbative quantum gravity effects peculiar to string theory. In
particular, "exotic instantons" in un-oriented string compactifications with
D-branes extending the (supersymmetric) standard model could indirectly produce
an effective operator delta{m} n^t n+h.c. In a specific model with an extra
vector-like pair of `quarks', acquiring a large mass proportional to the string
mass scale (exponentially suppressed by a function of the string moduli
fields), delta{m} can turn out to be as low as 10^{-24}-10^{-25} eV. The
induced neutron-antineutron oscillations could take place with a time scale
tau_{n\bar{n}} > 10^8 s, that could be tested by the next generation of
experiments. On the other hand, proton decay and FCNC's are automatically
strongly suppressed and are compatible with the current experimental limits.
Depending on the number of brane intersections, the model may also lead to the
generation of Majorana masses for R-handed neutrini. Our proposal could also
suggest neutron-neutralino or neutron-axino oscillations, with implications in
UCN, Dark Matter Direct Detection, UHECR and Neutron-Antineutron oscillations.
This suggests to improve the limits on neutron-antineutron oscillations, as a
possible test of string theory and quantum gravity.Comment: 35 pages, 11 figures. More comments on neutron-neutralino mixin
Specificity profile of venlafaxine and sertraline in major depression: metaregression of double-blind, randomized clinical trials
Social adjustment among treatment responder patients with mood disorders
Background: Patients with major depression (MD) show reduced social adjustment when compared with healthy controls. However, even among treatment responders, significant differences in social adjustment occur. The main aim of the present work is to study several socio-demographic and clinical variables possibly influencing social adjustment in MD patients who responded to treatment. Methods: Two hundred and eleven MD patients experiencing a depressive episode who responded to their current treatment were recruited within the context of a large European multicentre project. Our primary outcome measure was the association between 19 socio-demographic and clinical variables and total social adjustment scores, as measured with the Social Adjustment Scale (SAS). Secondary outcome measures included the associations between the same variables and SAS sub-scales, and the associations between these variables and self-esteem, as measured with the Rosenberg Self-Esteem Scale. Results: A co-morbidity with anxiety disorders and the severity of residual depression symptoms were the strongest independent factors associated with poorer social adjustment, in terms of total and most sub-areas' SAS scores. Other variables associated with total and sub-areas' SAS scores were identified as well, although some variations across different areas were observed. Limitations: The cross-sectional design, the retrospective assessment of data and the lack of a placebo control group. Conclusions: Our results confirm that a co-morbidity with anxiety disorders and higher residual depression symptoms could reduce social adjustment among responder MD patients. Further longitudinal studies are needed to confirm our results. © 2013 Elsevier B.V. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Social adjustment among treatment responder patients with mood disorders
Background: Patients with major depression (MD) show reduced social adjustment when compared with healthy controls. However, even among treatment responders, significant differences in social adjustment occur. The main aim of the present work is to study several socio-demographic and clinical variables possibly influencing social adjustment in MD patients who responded to treatment. Methods: Two hundred and eleven MD patients experiencing a depressive episode who responded to their current treatment were recruited within the context of a large European multicentre project. Our primary outcome measure was the association between 19 socio-demographic and clinical variables and total social adjustment scores, as measured with the Social Adjustment Scale (SAS). Secondary outcome measures included the associations between the same variables and SAS sub-scales, and the associations between these variables and self-esteem, as measured with the Rosenberg Self-Esteem Scale. Results: A co-morbidity with anxiety disorders and the severity of residual depression symptoms were the strongest independent factors associated with poorer social adjustment, in terms of total and most sub-areas' SAS scores. Other variables associated with total and sub-areas' SAS scores were identified as well, although some variations across different areas were observed. Limitations: The cross-sectional design, the retrospective assessment of data and the lack of a placebo control group. Conclusions: Our results confirm that a co-morbidity with anxiety disorders and higher residual depression symptoms could reduce social adjustment among responder MD patients. Further longitudinal studies are needed to confirm our results. © 2013 Elsevier B.V. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
PPP3CC gene: A putative modulator of antidepressant response through the B-cell receptor signaling pathway
Antidepressant pharmacogenetics represents a stimulating, but often discouraging field. The present study proposes a combination of several methodologies across three independent samples. Genes belonging to monoamine, neuroplasticity, circadian rhythm and transcription factor pathways were investigated in two samples (n=369 and 88) with diagnosis of major depression who were treated with antidepressants. Phenotypes were response, remission and treatment-resistant depression. Logistic regression including appropriate covariates was performed. Genes associated with outcomes were investigated in the STAR∗D (Sequenced Treatment Alternatives to Relieve Depression) genome-wide study (n=1861). Top genes were further studied through a pathway analysis. In both original samples, markers associated with outcomes were concentrated in the PPP3CC gene. Other interesting findings were particularly in the HTR2A gene in one original sample and the STAR∗D. The B-cell receptor signaling pathway proved to be the putative mediator of PPP3CC's effect on antidepressant response (P=0.03). Among innovative candidates, PPP3CC, involved in the regulation of immune system and synaptic plasticity, seems promising for further investigation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Nine differentially expressed genes from a post mortem study and their association with suicidal status in a sample of suicide completers, attempters and controls
none16siSeveral lines of evidence indicate that suicidal behaviour is partly heritable, with multiple genes implicated in its aetiology. We focused on nine genes (S100A13, EFEMP1, PCDHB5, PDGFRB, CDCA7L, SCN2B, PTPRR, MLC1 and ZFP36) which we previously detected as differentially expressed in the cortex of suicide victims compared to controls. We investigated 84 variants within these genes in 495 suicidal subjects (299 completers and 196 attempters) and 1513 controls (109 post-mortem and 1404 healthy). We evaluated associations with: 1) suicidal phenotype; 2) possible endophenotypes for suicidal behaviour. Overall positive results did not survive the correction threshold. However, we found a nominally different distribution of EFEMP1 genotypes, alleles and haplotypes between suicidal subjects and controls, results that were partially replicated when we separately considered the subgroup of suicide completers and post-mortem controls. A weaker association emerged also for PTPRR. Both EFEMP1 and PTPRR genes were also related to possible endophenotypes for suicidal behaviour such as anger, depression-anxiety and fatigue. Because of the large number of analyses performed and the low significance values further replication are mandatory. Nevertheless, neurotrophic gene variants, in particular EFEMP1 and PTPRR, may have a role in the pathogenesis of suicidal behaviour.noneBalestri, Martina; Crisafulli, Concetta; Donato, Luigi; Giegling, Ina; Calati, Raffaella; Antypa, Niki; Schneider, Barbara; Marusic, Dragan; Tarozzi, Maria Eugenia; Marusic, Dorjan; Paragi, Metka; Hartmann, Annette M.; Konte, Bettina; Marsano, Agnese; Serretti, Alessandro; Rujescu, DanBalestri, Martina; Crisafulli, Concetta; Donato, Luigi; Giegling, Ina; Calati, Raffaella; Antypa, Niki; Schneider, Barbara; Marusic, Dragan; Tarozzi, Maria Eugenia; Marusic, Dorjan; Paragi, Metka; Hartmann, Annette M.; Konte, Bettina; Marsano, Agnese; Serretti, Alessandro; Rujescu, Da
Effects of SORL1 Gene on Alzheimer's Disease. Focus on Gender, Neuropsychiatric Symptoms and Pro-Inflammatory Cytokines
It was suggested that the gene encoding for sorLa, (SORL1) may affect
Alzheimer’s disease (LOAD) through a female-specific mechanism. The aims
of this study were to confirm the role of gender in modulating the
association between SORL1 and LOAD and to ascertain the influence of
SORL1 on cognitive impairment, neuropsychiatric symptoms (BPSD) and
secretion of pro-inflammatory cytokines.
Ninety six outpatients with LOAD and 120 unrelated controls were
genotyped for APOE and three SNPs at the 5’ end of SORL1(intron 6): SNP
8 (rs668387); SNP 9 (rs68902); SNP 10 (rs641120). Clinical evaluation
was made with the MMSE, Neuropsychiatric Inventory (NPI) and Cornell
Scale for Depression in Dementia (CDDS). ELISPOT assays were used to
measure pro-inflammatory cytokine (TNF-alpha; IL-6; IL-1beta; IFN-gamma)
production in peripheral blood mononuclear cell (PBMC) supernatant from
AD patients.
SORL1 SNPs were not associated with LOAD in overall sample. Instead the
G-alleles at SNPs 9 (p=0.015) and 10 (p=0.015) and the CGG haplotype
(p=0.02) were associated with LOAD in the women subgroup. The TAA
haplotype was marginally protective in AD patients being associated with
lower BPSD scores (p=0.01). The same haplotype was also associated with
higher IL-1beta (p=0.01) production. These genetic effects were not
modified by APOE4 allele and controlled for illness duration and
treatment.
In conclusion, SORL1 does not appear to be a major risk factor for LOAD.
Its contribution could be underestimated in our small sample.
Sex-specific factors could modulate the association between SORL1 and
AD. The influence of SORL1 variants on production of inflammatory
cytokines warrants further investigation
Temperament and character inventory in bipolar disorder versus healthy controls and modulatory effects of 3 key functional gene variants
Background: Bipolar disorder (BD) has been associated with temperamental and personality traits, although the relationship is still to be fully elucidated. Several studies investigated the genetic basis of temperament and character, identifying catechol-O-methyltransferase (COMT), brain derived neurotrophic factor (BDNF), and serotonin transporter (5-HTT) gene variants as strong candidates. Methods: In the GECO-BIP study, 125 BD patients and 173 HC were recruited. Subjects underwent to a detailed assessment and the temperament and character inventory 125 items (TCI) was administrated. Three functional genetic variants within key candidate genes (COMT rs4680, BDNF rs6265, and the serotonin-transporter-linked polymorphic region (5-HTTLPR)) were genotyped. Univariate and multivariate analyses were performed. Results: Compared to HC, BD patients showed higher scores in novelty seeking (NS; p = 0.001), harm avoidance (HA; p < 0.001), and self transcendence (St; p < 0.001), and lower scores in self directness (p < 0.001) and cooperativeness (p < 0.001) TCI dimensions. Concerning the genetic analyses, COMT rs4680 was associated with NS in the total sample (p = 0.007) and in the male subsample (p = 0.022). When performing the analysis in the HC and BD samples, the association was confirmed only in HC (p = 0.012), and in the HC male subgroup in particular (p = 0.004). BDNF rs6265 was associated with St in the BD group (p = 0.017). Conclusion: COMT rs4680 may modulate NS in males in the general population. This effect was not detected in BD patients, probably because BD alters the neurobiological basis of some TCI dimensions. BDNF rs6265 seems to modulate St TCI dimension only in BD patients, possibly modulating the previously reported association between rs6265 and BD treatment response. Further studies are needed to confirm our findings