86 research outputs found
EGF as a New Therapeutic Target for Medulloblastoma Metastasis
Medulloblastoma (MB) is a malignant pediatric brain tumor known for its aggressive metastatic potential. Despite the well-documented migration of MB cells to other parts of the brain and spinal column, MB chemotaxis is poorly understood. Herein, we examined the in vitro migratory and cellular responses of MB-derived cells to external signaling of Epidermal Growth Factor (EGF), hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF-BB), and the stromal cellderived factors 1-alpha (SDF-1). Experiments utilized transwell assays and immunocytochemistry to identify receptor activation in MB migration, and used a microfluidic platform to examine directionality, trajectory, and gradient-dependence of motile cells. Data illustrates that MB-derived cells respond strongly to EGF in a dosage and gradient-dependent manner with increased EGF-R activation, and show that high EGF gradient fields cause an increased number of cells to migrate longer directed distances. Our results provide evidence that EGF and its receptor play an important role than previously documented in MB chemotactic migration than previously documented and should be considered for developing migration-target therapies against MB metastasi
G28.17+0.05: An unusual giant HI cloud in the inner Galaxy
New 21 cm HI observations have revealed a giant HI cloud in the Galactic
plane that has unusual properties. It is quite well defined, about 150 pc in
diameter at a distance of 5 kpc, and contains as much as 100,000 Solar Masses
of atomic hydrogen. The outer parts of the cloud appear in HI emission above
the HI background, while the central regions show HI self-absorption. Models
which reproduce the observations have a core with a temperature <40 K and an
outer envelope as much as an order of magnitude hotter. The cold core is
elongated along the Galactic plane, whereas the overall outline of the cloud is
approximately spherical. The warm and cold parts of the HI cloud have a
similar, and relatively large, line width of approximately 7 km/s. The cloud
core is a source of weak, anomalously-excited 1720 MHz OH emission, also with a
relatively large line width, which delineates the region of HI self-absorption
but is slightly blue-shifted in velocity. The intensity of the 1720 MHz OH
emission is correlated with N(H) derived from models of the cold core. There is
12CO emission associated with the cloud core. Most of the cloud mass is in
molecules, and the total mass is > 200,000 Solar Masses. In the cold core the
HI mass fraction may be 10 percent. The cloud has only a few sites of current
star formation. There may be about 100 more objects like this in the inner
Galaxy; every line of sight through the Galactic plane within 50 degrees of the
Galactic center probably intersects at least one. We suggest that G28.17+0.05
is a cloud being observed as it enters a spiral arm and that it is in the
transition from the atomic to the molecular state.Comment: 35 pages, inludes 12 figure
Sertraline and mirtazapine versus placebo in subgroups of depression in dementia: findings from the HTA-SADD randomized controlled trial
Objective
Studies have shown that antidepressants are no better than placebo in treating depression in dementia. The authors examined antidepressant efficacy in subgroups of depression in dementia with different depressive symptom profiles.
Methods
This study focuses on exploratory secondary analyses on the randomized, parallel-group, double-blind, placebo-controlled Health Technology Assessment Study of the Use of Antidepressants for Depression in Dementia (HTA-SADD) trial. The setting included old-age psychiatry services in nine centers in England. The participants included 326 patients meeting National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association probable/possible Alzheimer disease criteria, and Cornell Scale for Depression in Dementia (CSDD) scores of 8 or more. Intervention was placebo (nâŻ=âŻ111), sertraline (nâŻ=âŻ107), or mirtazapine (nâŻ=âŻ108). Latent class analyses (LCA) on baseline CSDD items clustered participants into symptom-based subgroups. Mixed-model analysis evaluated CSDD improvement at 13 and 39 weeks by randomization in each subgroup.
Results
LCA yielded 4 subgroups: severe (nâŻ=âŻ34), psychological (nâŻ=âŻ86), affective (nâŻ=âŻ129), and somatic (nâŻ=âŻ77). Mirtazapine, but not sertraline, outperformed placebo in the psychological subgroup at week 13 (adjusted estimate: â2.77 [standard error (SE) 1.16; 95% confidence interval: â5.09 to â0.46]), which remained, but lost statistical significance at week 39 (adjusted estimate: â2.97 [SE 1.59; 95% confidence interval: â6.15 to 0.20]). Neither sertraline nor mirtazapine outperformed placebo in the other subgroups.
Conclusion
Because of the exploratory nature of the analyses and the small sample sizes for subgroup analysis there is the need for caution in interpreting these data. Replication of the potential effects of mirtazapine in the subgroup of those with depression in dementia with âpsychologicalâ symptoms would be valuable. These data should not change clinical practice, but future trials should consider stratifying types of depression in dementia in secondary analyses
Trace amine-associated receptor 1 (TAAR1) agonists for psychosis: protocol for a living systematic review and meta-analysis of human and non-human studies
Background: There is an urgent need to develop more effective and
safer antipsychotics beyond dopamine 2 receptor antagonists. An
emerging and promising approach is TAAR1 agonism. Therefore, we
will conduct a living systematic review and meta-analysis to synthesize and triangulate the evidence from preclinical animal experiments and
clinical studies on the efficacy, safety, and underlying mechanism of
action of TAAR1 agonism for psychosis.
Methods: Independent searches will be conducted in multiple
electronic databases to identify clinical and animal experimental
studies comparing TAAR1 agonists with licensed antipsychotics or
other control conditions in individuals with psychosis or animal
models for psychosis, respectively. The primary outcomes will be
overall psychotic symptoms and their behavioural proxies in animals.
Secondary outcomes will include side effects and neurobiological
measures. Two independent reviewers will conduct study selection,
data extraction using predefined forms, and risk of bias assessment
using suitable tools based on the study design. Ontologies will be
developed to facilitate study identification and data extraction. Data
from clinical and animal studies will be synthesized separately using
random-effects meta-analysis if appropriate, or synthesis without
meta-analysis. Study characteristics will be investigated as potential
sources of heterogeneity. Confidence in the evidence for each
outcome and source of evidence will be evaluated, considering the
summary of the association, potential concerns regarding internal
and external validity, and reporting biases. When multiple sources of
evidence are available for an outcome, an overall conclusion will be
drawn in a triangulation meeting involving a multidisciplinary team of
experts. We plan trimonthly updates of the review, and any
modifications in the protocol will be documented. The review will be
co-produced by multiple stakeholders aiming to produce impactful
and relevant results and bridge the gap between preclinical and
clinical research on psychosis
Trace amine-associated receptor 1 (TAAR1) agonists for psychosis:protocol for a living systematic review and meta-analysis of human and non-human studies
BACKGROUND: There is an urgent need to develop more effective and safer antipsychotics beyond dopamine 2 receptor antagonists. An emerging and promising approach is TAAR1 agonism. Therefore, we will conduct a living systematic review and meta-analysis to synthesize and triangulate the evidence from preclinical animal experiments and clinical studies on the efficacy, safety, and underlying mechanism of action of TAAR1 agonism for psychosis.METHODS: Independent searches will be conducted in multiple electronic databases to identify clinical and animal experimental studies comparing TAAR1 agonists with licensed antipsychotics or other control conditions in individuals with psychosis or animal models for psychosis, respectively. The primary outcomes will be overall psychotic symptoms and their behavioural proxies in animals. Secondary outcomes will include side effects and neurobiological measures. Two independent reviewers will conduct study selection, data extraction using predefined forms, and risk of bias assessment using suitable tools based on the study design. Ontologies will be developed to facilitate study identification and data extraction. Data from clinical and animal studies will be synthesized separately using random-effects meta-analysis if appropriate, or synthesis without meta-analysis. Study characteristics will be investigated as potential sources of heterogeneity. Confidence in the evidence for each outcome and source of evidence will be evaluated, considering the summary of the association, potential concerns regarding internal and external validity, and reporting biases. When multiple sources of evidence are available for an outcome, an overall conclusion will be drawn in a triangulation meeting involving a multidisciplinary team of experts. We plan trimonthly updates of the review, and any modifications in the protocol will be documented. The review will be co-produced by multiple stakeholders aiming to produce impactful and relevant results and bridge the gap between preclinical and clinical research on psychosis.PROTOCOL REGISTRATION: PROSPERO-ID: CRD42023451628.</p
Variability and magnitude of brain glutamate levels in schizophrenia:a meta and mega-analysis
Glutamatergic dysfunction is implicated in schizophrenia pathoaetiology, but this may vary in extent between patients. It is unclear whether inter-individual variability in glutamate is greater in schizophrenia than the general population. We conducted meta-analyses to assess (1) variability of glutamate measures in patients relative to controls (log coefficient of variation ratio: CVR); (2) standardised mean differences (SMD) using Hedges g; (3) modal distribution of individual-level glutamate data (Hartiganâs unimodality dip test). MEDLINE and EMBASE databases were searched from inception to September 2022 for proton magnetic resonance spectroscopy (1H-MRS) studies reporting glutamate, glutamine or Glx in schizophrenia. 123 studies reporting on 8256 patients and 7532 controls were included. Compared with controls, patients demonstrated greater variability in glutamatergic metabolites in the medial frontal cortex (MFC, glutamate: CVR = 0.15, p < 0.001; glutamine: CVR = 0.15, p = 0.003; Glx: CVR = 0.11, p = 0.002), dorsolateral prefrontal cortex (glutamine: CVR = 0.14, p = 0.05; Glx: CVR = 0.25, p < 0.001) and thalamus (glutamate: CVR = 0.16, p = 0.008; Glx: CVR = 0.19, p = 0.008). Studies in younger, more symptomatic patients were associated with greater variability in the basal ganglia (BG glutamate with age: z = â0.03, p = 0.003, symptoms: z = 0.007, p = 0.02) and temporal lobe (glutamate with age: z = â0.03, p = 0.02), while studies with older, more symptomatic patients associated with greater variability in MFC (glutamate with age: z = 0.01, p = 0.02, glutamine with symptoms: z = 0.01, p = 0.02). For individual patient data, most studies showed a unimodal distribution of glutamatergic metabolites. Meta-analysis of mean differences found lower MFC glutamate (g = â0.15, p = 0.03), higher thalamic glutamine (g = 0.53, p < 0.001) and higher BG Glx in patients relative to controls (g = 0.28, p < 0.001). Proportion of males was negatively associated with MFC glutamate (z = â0.02, p < 0.001) and frontal white matter Glx (z = â0.03, p = 0.02) in patients relative to controls. Patient PANSS total score was positively associated with glutamate SMD in BG (z = 0.01, p = 0.01) and temporal lobe (z = 0.05, p = 0.008). Further research into the mechanisms underlying greater glutamatergic metabolite variability in schizophrenia and their clinical consequences may inform the identification of patient subgroups for future treatment strategies.</p
- âŠ