The efficacy of a nanosynthetic bone graft substitute as a bone graft extender in rabbit posterolateral fusion.

Background Context: Synthetic bone graft substitutes are commonly used in spinal fusion surgery. Preclinical data in a model of spinal fusion to support their efficacy is an important component in clinical adoption to understand how these materials provide a biological and mechanical role in spinal fusion.

Purpose: To evaluate the in vivo response of a nanosynthetic silicated calcium phosphate putty (OstP) combined with autograft compared to autograft alone or a collagen-biphasic calcium phosphate putty (MasP) combined with autograft in a rabbit spinal fusion model.

Unusual presentation and urinary tract obstruction due to disseminated intra-abdominal caused by species in a dog.

Intra-abdominal eumycetomas are rare in dogs and usually attributed to contamination of surgical wounds post-operatively. This is the first report of extensively disseminated intra-abdominal eumycetomas due to resulting in urinary tract obstruction and associated chronic recurrent urinary tract infections in a Labrador retriever. Identification of the fungal genus was performed on samples obtained from culture of eumycetomic fungal grains that had been collected sterilely at necropsy.

Testosterone, Cortisol and Financial Risk-Taking.

Both testosterone and cortisol have major actions on financial decision-making closely related to their primary biological functions, reproductive success and response to stress, respectively. Financial risk-taking represents a particular example of strategic decisions made in the context of choice under conditions of uncertainty. Such decisions have multiple components, and this article considers how much we know of how either hormone affects risk-appetite, reward value, information processing and estimation of the costs and benefits of potential success or failure, both personal and social.

Testosterone administration does not affect men's rejections of low ultimatum game offers or aggressive mood.

Correlative evidence suggests that testosterone promotes dominance and aggression. However, causal evidence is scarce and offers mixed results. To investigate this relationship, we administered testosterone for 48h to 41 healthy young adult men in a within-subjects, double-blind placebo-controlled balanced crossover design.

Circadian and ultradian glucocorticoid rhythmicity: Implications for the effects of glucocorticoids on neural stem cells and adult hippocampal neurogenesis.

Psychosocial stress, and within the neuroendocrine reaction to stress specifically the glucocorticoid hormones, are well-characterized inhibitors of neural stem/progenitor cell proliferation in the adult hippocampus, resulting in a marked reduction in the production of new neurons in this brain area relevant for learning and memory. However, the mechanisms by which stress, and particularly glucocorticoids, inhibit neural stem/progenitor cell proliferation remain unclear and under debate. Here we review the literature on the topic and discuss the evidence for direct and indirect effects of glucocorticoids on neural stem/progenitor cell proliferation and adult neurogenesis.

Depression as a risk factor for Alzheimer's disease: Genes, steroids, cytokines and neurogenesis - What do we need to know?

Depression (MDD) is prodromal to, and a component of, Alzheimer's disease (AD): it may also be a trigger for incipient AD. MDD is not a unitary disorder, so there may be particular subtypes of early life MDD that pose independent high risks for later AD, though the identification of these subtypes is problematical. There may either be a common pathological event underlying both MDD and AD, or MDD may sensitize the brain to a second event ('hit') that precipitates AD.

Cortisol and testosterone increase financial risk taking and may destabilize markets.

It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders' financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets.

Maternal postnatal depression predicts altered offspring biological stress reactivity in adulthood.

The offspring of depressed parents have been found to show elevated basal levels of the stress hormone cortisol. Whether heightened cortisol stress reactivity is also present in this group has yet to be clearly demonstrated. We tested whether postnatal maternal depression predicts subsequent increases in offspring biological sensitivity to social stress, as indexed by elevated cortisol reactivity.

Childhood adversity subtypes and depressive symptoms in early and late adolescence.

Within a longitudinal study of 1,005 adolescents, we investigated how exposure to childhood psychosocial adversities was associated with the emergence of depressive symptoms between 14 and 17 years of age. The cohort was classified into four empirically determined adversity subtypes for two age periods in childhood (0-5 and 6-11 years). One subtype reflects normative/optimal family environments (n = 692, 69%), while the other three subtypes reflect differential suboptimal family environments (aberrant parenting: n = 71, 7%; discordant: n = 185, 18%; and hazardous: n = 57, 6%).

Elevated morning cortisol is a stratified population-level biomarker for major depression in boys only with high depressive symptoms.

Major depressive disorder (MD) is a debilitating public mental health problem with severe societal and personal costs attached. Around one in six people will suffer from this complex disorder at some point in their lives, which has shown considerable etiological and clinical heterogeneity. Overall there remain no validated biomarkers in the youth population at large that can aid the detection of at-risk groups for depression in general and for boys and young men in particular.

Functional polymorphism in the brain-derived neurotrophic factor gene interacts with stressful life events but not childhood maltreatment in the etiology of depression.

Background: We test the hypothesis that the functional Val66Met polymorphism of BDNF interacts with recent life events to produce onset of new depressive episodes. We also explore the possibility that the Met allele of this polymorphism interacts with childhood maltreatment to increase the risk of chronic depression.

Methods: In a risk-enriched combined sample of unrelated women, childhood maltreatment and current life events were measured with the Childhood Experience of Care and Abuse, and Life Events and Difficulties Schedule interviews.

Serotonin transporter length polymorphism, childhood maltreatment, and chronic depression: a specific gene-environment interaction.

Background: Key questions about the interaction between the serotonin transporter length polymorphism (5-HTTLPR) and stress in the etiology of depression remain unresolved. We test the hypotheses that the interaction is restricted to childhood maltreatment (as opposed to stressful events in adulthood), and leads to chronic depressive episodes (as opposed to any onset of depression), using gold-standard assessments of childhood maltreatment, severe life events, chronic depression, and new depressive onsets.

Method: In a risk-enriched sample of 273 unrelated women, childhood maltreatment was retrospectively assessed with the Childhood Experience of Care and Abuse (CECA) interview and 5-HTTLPR was genotyped.

Cultured subventricular zone progenitor cells transduced with neurogenin-2 become mature glutamatergic neurons and integrate into the dentate gyrus.

We have previously shown that transplantation of immature DCX+/NeuN+/Prox1+ neurons (found in the neonatal DG), but not undifferentiated neuronal progenitor cells (NPCs) from ventral subventricular zone (SVZ), results in neuronal maturation in vivo within the dentate niche. Here we investigated whether we could enhance the integration of SVZ NPCs by forced expression of the proneural gene Neurogenin 2 (NEUROG2). NPCs cultured from neonatal GFP-transgenic rat SVZ for 7 days in a non-differentiating medium were transduced with a retrovirus encoding NEUROG2 and DsRed or the DsRed reporter gene alone (control).

Depressive symptoms during adolescence: comparison between epidemiological and high risk sampling.

Purpose: Both epidemiological (unselected) and high risk (screening on known risk criteria) samplings have been used to investigate the course of affective disorders. Selecting individuals on multiple risk criteria may create a sample not comparable to individuals with similar risk criteria within the general population. This study compared depressive symptoms across the two sampling methods to test this possibility.

Cortisol levels in response to starting school in children at increased risk for social phobia.

Background: Research on depression has identified hyperactivity of the HPA axis as a potential contributory factor to the intergenerational transmission of affective symptoms. This has not yet been examined in the context of social phobia. The current study compared HPA axis activity in response to a universal social stressor (starting school) in children of 2 groups of women: one with social phobia and one with no history of anxiety (comparison group).

Profiles of family-focused adverse experiences through childhood and early adolescence: the ROOTS project a community investigation of adolescent mental health.

Background: Adverse family experiences in early life are associated with subsequent psychopathology. This study adds to the growing body of work exploring the nature and associations between adverse experiences over the childhood years.

Methods: Primary carers of 1143 randomly recruited 14-year olds in Cambridgeshire and Suffolk, UK were interviewed using the Cambridge Early Experiences Interview (CAMEEI) to assess family-focused adversities.

Novel control by the CA3 region of the hippocampus on neurogenesis in the dentate gyrus of the adult rat.

The dentate gyrus is a site of continued neurogenesis in the adult brain. The CA3 region of the hippocampus is the major projection area from the dentate gyrus. CA3 sends reciprocal projections back to the dentate gyrus.

Cell origin and culture history determine successful integration of neural precursor transplants into the dentate gyrus of the adult rat.

The success of transplants of neural tissue into the adult dentate gyrus in generating mature neurons is highly variable. Here we address the roles of the origin of the tissue and its pre-implantation preparation, and show that both are critical. We transplanted neonatal cultured or primary rat cells from either the ventral subventricular zone (vSVZ) or the dentate gyrus (DG) into the adult rat DG.

The roles of BDNF, pCREB and Wnt3a in the latent period preceding activation of progenitor cell mitosis in the adult dentate gyrus by fluoxetine.

The formation of new neurons continues into adult life in the dentate gyrus of the rat hippocampus, as in many other species. Neurogenesis itself turns out to be highly labile, and is regulated by a number of factors. One of these is the serotoninergic system: treatment with drugs (such as the SSRI fluoxetine) markedly stimulates mitosis in the progenitor cells of the dentate gyrus.

Polymorphisms in BDNF (Val66Met) and 5-HTTLPR, morning cortisol and subsequent depression in at-risk adolescents.

Background: There is increasing evidence for genetic effects on the hypothalamic-pituitary axis system. More than one gene is likely to moderate corticoid-mediated activity.

Aims: To investigate whether the brain-derived neurotrophic factor (BDNF) polymorphism (rs6265, Val66Met) is associated with morning waking salivary cortisol and moderates the corticoid-mediated risk for subsequent depressive episode onset independently of the known effects of 5-HTTLPR (the serotonin transporter gene promoter).

Effect of agomelatine and its interaction with the daily corticosterone rhythm on progenitor cell proliferation in the dentate gyrus of the adult rat.

Agomelatine, a novel melatonin analogue and anti-depressant that acts as an agonist on melatonin receptors 1 and 2 and as an antagonist at the 5HT2C receptor, was tested for its effects on cell proliferation in the dentate gyrus of the adult rat hippocampus under intact and flattened corticosterone rhythm conditions. Agomelatine stimulated mitosis rates in the intact male rat. Flattening the daily corticosterone rhythm by inserting a subcutaneous pellet of this steroid prevented the action of agomelatine.

Disturbances in early parenting of depressed mothers and cortisol secretion in offspring: a preliminary study.

Background: Disturbances in cortisol secretion are associated with risk for psychiatric disorder, including depression. Animal research indicates that early care experiences influence hypothalamic-pituitary-adrenal (HPA) axis functioning in offspring. Similar effects are suggested in human development, but evidence of longitudinal associations between observed early parenting and offspring cortisol secretion is extremely limited.

Serotonin transporter genotype, morning cortisol and subsequent depression in adolescents.

Background: The short (s) allele of the serotonin transporter gene promoter (5-HTTLPR) may be associated with exposure to social adversities and the subsequent onset of depressive illness in adulthood.

Aims: To test in adolescents at high risk for depression whether the short 's' allele is associated with levels of morning cortisol and the subsequent onset of a depressive episode.

Method: High-risk adolescents (n = 403) were genotyped for 5-HTTLPR.