14 research outputs found
Prognosis in human glioblastoma based on expression of ligand growth hormone-releasing hormone, pituitary-type growth hormone-releasing hormone receptor, its splicing variant receptors, EGF receptor and PTEN genes
Purpose G lioblastoma (GB) is the most frequent brain
tumor. Despite recent improvement in therapeutic strategies,
the prognosis of GB remains poor. Growth hormone-releasing
hormone (GHRH) may act as a growth factor; antagonists
of GHRH have been successfully applied for experimental
treatment of different types of tumors. The expression profile
of GHRH receptor, its main splice variant SV1 and GHRH
have not been investigated in human GB tissue samples.
Methods We examined the expression of GHRH, fulllength
pituitary-type GHRH receptor (pGHRHR), its functional
splice variant SV1 and non-functional SV2 by RTPCR
in 23 human GB specimens. Epidermal growth factor
receptor (EGFR) and phosphatase and tensin homolog gene
(PTEN) expression levels were also evaluated by quantitative
RT-PCR. Correlations between clinico-pathological
parameters and gene expressions were analyzed.
Results E xpression of GHRH was found to be positive
in 61.9 % of samples. pGHRH receptor was not expressed
in our sample set, while SV1 could be detected in 17.4 %
and SV2 in 8.6 % of the GB tissues. In 65.2 and 78.3 %
of samples, significant EGFR over-expression or PTEN
under-representation could be detected, respectively. In
47.8 % of cases, EGFR up-regulation and PTEN down-regulation
occurred together. Survival was significantly poorer
in tumors lacking GHRH expression. This worse prognosis
in GHRH negative group remained significant even if SV1
was also expressed.
Conclusion Our study shows that GHRH and SV1 genes
expressed in human GB samples and their expression patterns
are associated with poorer prognosis
Subcortical brain alterations in major depressive disorder:findings from the ENIGMA Major Depressive Disorder working group
The pattern of structural brain alterations associated with major depressive disorder (MDD) remains unresolved. This is in part due to small sample sizes of neuroimaging studies resulting in limited statistical power, disease heterogeneity and the complex interactions between clinical characteristics and brain morphology. To address this, we meta-analyzed three-dimensional brain magnetic resonance imaging data from 1728 MDD patients and 7199 controls from 15 research samples worldwide, to identify subcortical brain volumes that robustly discriminate MDD patients from healthy controls. Relative to controls, patients had significantly lower hippocampal volumes (Cohen's d=-0.14, % difference=-1.24). This effect was driven by patients with recurrent MDD (Cohen's d=-0.17, % difference=-1.44), and we detected no differences between first episode patients and controls. Age of onset <= 21 was associated with a smaller hippocampus (Cohen's d=-0.20, % difference=-1.85) and a trend toward smaller amygdala (Cohen's d=-0.11, % difference=-1.23) and larger lateral ventricles (Cohen's d=0.12, % difference=5.11). Symptom severity at study inclusion was not associated with any regional brain volumes. Sample characteristics such as mean age, proportion of antidepressant users and proportion of remitted patients, and methodological characteristics did not significantly moderate alterations in brain volumes in MDD. Samples with a higher proportion of antipsychotic medication users showed larger caudate volumes in MDD patients compared with controls. This currently largest worldwide effort to identify subcortical brain alterations showed robust smaller hippocampal volumes in MDD patients, moderated by age of onset and first episode versus recurrent episode status
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Subcortical brain structure and suicidal behaviour in major depressive disorder: a meta-analysis from the ENIGMA-MDD working group.
The aetiology of suicidal behaviour is complex, and knowledge about its neurobiological mechanisms is limited. Neuroimaging methods provide a noninvasive approach to explore the neural correlates of suicide vulnerability in vivo. The ENIGMA-MDD Working Group is an international collaboration evaluating neuroimaging and clinical data from thousands of individuals collected by research groups from around the world. Here we present analyses in a subset sample (n=3097) for whom suicidality data were available. Prevalence of suicidal symptoms among major depressive disorder (MDD) cases ranged between 29 and 69% across cohorts. We compared mean subcortical grey matter volumes, lateral ventricle volumes and total intracranial volume (ICV) in MDD patients with suicidal symptoms (N=451) vs healthy controls (N=1996) or MDD patients with no suicidal symptoms (N=650). MDD patients reporting suicidal plans or attempts showed a smaller ICV (P=4.12 × 10-3) or a 2.87% smaller volume compared with controls (Cohen's d=-0.284). In addition, we observed a nonsignificant trend in which MDD cases with suicidal symptoms had smaller subcortical volumes and larger ventricular volumes compared with controls. Finally, no significant differences (P=0.28-0.97) were found between MDD patients with and those without suicidal symptoms for any of the brain volume measures. This is by far the largest neuroimaging meta-analysis of suicidal behaviour in MDD to date. Our results did not replicate previous reports of association between subcortical brain structure and suicidality and highlight the need for collecting better-powered imaging samples and using improved suicidality assessment instruments
Model-based optimization of the operation of the coke calcining kiln
A mathematical model was recently developed to simulate the calcination process of regular petroleum coke suitable for aluminum industry applications. The model is made of 14 ordinary differential equations describing energy and mass conservation in the gas and in the coke bed, and complemented by correlations and algebraic equations. It calculates temperature and concentration profiles in the kiln, and also yields other information important to kiln operation, such as calcined coke recovery factor and coke loss through the generation of dust. In this paper it is demonstrated that the model is an efficient tool for the optimization of kiln operation. The model is used to study the effect of key control variables upon kiln operation and productivity. Further, it is shown that higher kiln productivity may be obtained with optimized kiln control and without loss of satisfactory kiln operating condition
Structural brain alterations in major depression: findings from the ENIGMA Major Depressive Disorder Working Group
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Subcortical brain alterations in major depressive disorder: findings from the ENIGMA Major Depressive Disorder working group.
The pattern of structural brain alterations associated with major depressive disorder (MDD) remains unresolved. This is in part due to small sample sizes of neuroimaging studies resulting in limited statistical power, disease heterogeneity and the complex interactions between clinical characteristics and brain morphology. To address this, we meta-analyzed three-dimensional brain magnetic resonance imaging data from 1728 MDD patients and 7199 controls from 15 research samples worldwide, to identify subcortical brain volumes that robustly discriminate MDD patients from healthy controls. Relative to controls, patients had significantly lower hippocampal volumes (Cohen's d=-0.14, % difference=-1.24). This effect was driven by patients with recurrent MDD (Cohen's d=-0.17, % difference=-1.44), and we detected no differences between first episode patients and controls. Age of onset ⩽21 was associated with a smaller hippocampus (Cohen's d=-0.20, % difference=-1.85) and a trend toward smaller amygdala (Cohen's d=-0.11, % difference=-1.23) and larger lateral ventricles (Cohen's d=0.12, % difference=5.11). Symptom severity at study inclusion was not associated with any regional brain volumes. Sample characteristics such as mean age, proportion of antidepressant users and proportion of remitted patients, and methodological characteristics did not significantly moderate alterations in brain volumes in MDD. Samples with a higher proportion of antipsychotic medication users showed larger caudate volumes in MDD patients compared with controls. This currently largest worldwide effort to identify subcortical brain alterations showed robust smaller hippocampal volumes in MDD patients, moderated by age of onset and first episode versus recurrent episode status