1,720,991 research outputs found
Impact of acute inflammation on neurogenesis in rat subventricular zone. Proceedings of the 63rd Congress of the Italian Embryological Group (GEI)
No full textSchizophrenia and neurogenesis. A stem cell approach
No full textSeveral recent research findings indicate that schizophrenia (SCZ) may begin with an abnormal neuro-genesis from embryonic Neural Stem Cells (NSCs) and that this process may be particularly vulnerable to a number of genetic and/or environmental disturbances of early brain development. Since it is now well known that neurogenesis is not confined to the womb, but is a protracted process continuing in postnatal life well into adolescence and beyond, and since in the majority of subjects diagnosed with SCZ the first psychotic break occurs in late adolescence or early adulthood, the aim of our paper is to summarize the main findings supporting a possible link between changes in developmental postnatal neurogenesis and SCZ, with a specific focus on the critical period of adolescence and associated environmental risk factors. Establishing a significant role of adult neurogenesis in the emergence of psychosis will help us not only to better understand the pathogenesis of this neuopsychiatric disorder, but also to provide the key to potential strategies toward possible treatments and/or early corrective interventions
VEGF inhibition alters neurotrophin signalling pathways and induces caspase-3 activation and autophagy in rabbit retina
No full textThis study sought to evaluate the prospective role exerted by vascular endothelial growth factor (VEGF) in the modulation of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) signalling pathways in the rabbit retina. To reach this aim, the anti-VEGF agents aflibercept and ranibizumab were used as a pharmacological approach to evaluate the putative consequences elicited by VEGF inhibition on neurotrophin signalling. VEGF inhibition determined a marked imbalance in proneurotrophin expression, a significant reduction in TrkA and TrkB phosphorylation states and a decrease in the pan-neurotrophin receptor p75. Importantly, VEGF blockade also caused a strong increase in cleaved caspase-3, beclin-1 and lipidated LC3. The effects were more pronounced in the aflibercept group when compared with ranibizumab-treated rabbits, particularly 1 week after injection. This study demonstrates that VEGF exerts pivotal physiological roles in regulating NGF and BDNF pathways in the retina, as its inhibition by anti-VEGF agents deeply impacts neurotrophin homeostasis. These events are accompanied by a sustained induction of apoptotic and autophagic markers, suggesting that anti-VEGF-dependent impairments in neurotrophin signalling could be responsible for the activation of retinal cell death pathways
NGF eye administration recovers the trkb and glutamate/GABA marker deficit in the adult visual cortex following optic nerve crush
No full textEye-drop recombinant human nerve growth factor (ed-rhNGF) has proved to recover the retina and optic nerve damage in animal models, including the unilateral optic nerve crush (ONC), and to improve visual acuity in humans. These data, associated with evidence that ed-rhNGF stimulates the brain derived neurotrophic factor (BDNF) in retina and cortex, suggests that NGF might exert retino-fugal effects by affecting BDNF and its receptor TrkB. To address these questions, their expression and relationship with the GABAergic and glutamatergic transmission markers, GAD65 and GAD67, vesicular inhibitory amino acid transporter (VGAT), and vesicular glutamate transporters 1 and 2 (VGLUT-1 and VGLUT-2) were investigated in adult ONC rats contralateral and ipsilateral visual cortex (VCx). Ed-rhNGF recovers the ONC-induced alteration of GABAergic and glutamatergic markers in contralateral VCx, induces an upregulation of TrkB, which is positively correlated with BDNF precursor (proBDNF) decrease in both VCx sides, and strongly enhances TrkB+ cell soma and neuronal endings surrounded by GAD65 immuno-reactive afferents. These findings contribute to enlarging the knowledge on the mechanism of actions and cellular targets of exogenously administrated NGF, and suggest that ed-rhNGF might act by po-tentiating the activity-dependent TrkB expression in GAD+ cells in VCx following retina damage and/or ONC
Evaluation of the effectiveness of BNT162b2 primary vaccination and booster dose to SARS-CoV-2 in eliciting stable mucosal immunity
Full text linkThe waning effectiveness of the primary vaccination for SARS-CoV-2 led to administration of an additional booster dose (BD). The efficacy of the BD in stimulating humoral systemic immune response is well established, but its effectiveness on inducing mucosal immune reaction has not yet been reported. To address this issue, we evaluated SARS-CoV-2-specific antibody responses in the serum, saliva, and tears after BNT162b2 (Pfizer/BioNTech, New York, NY, USA) vaccination and BD, as well as after SARS-CoV-2 infection. After two doses of BNT162b2 vaccine, we observed specific serum IgG in 100% and IgA in 97.2% of subjects, associated with mucosal response in both salivary samples (sIgA in 97.2% and IgG(S) in 58.8%) and in tears (sIgA in 77.8% and IgG(S) in 67.7%). BD induced a recovery of the systemic humoral response and of tear sIgA when compared to 6 months of follow-up titers (p < 0.001; p = 0.012). However, sIgA levels in both tears and saliva were significantly lower following BD when compared to patients with prior SARS-CoV-2 infection (p = 0.001 and p = 0.005, respectively). Our results demonstrated that administration of BD restored high serum levels of both IgG and IgA but had a poor effect in stimulating mucosal immunity when compared to prior SARS-CoV-2 infection
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Emotional stress induced by parachute jumping enhances blood nerve growth factor levels and the distribution of nerve growth factor receptors in lymphocytes
No full textWe examined the plasma nerve growth factor (NGF) level and the distribution of NGF receptors in peripheral lymphocytes of young soldiers (mean age, 20-24 yr) experiencing the thrill of a novice about to make their first parachute jumps. Blood was collected from soldiers who knew they were selected to jump (n = 26), as well as from soldiers who knew they were not selected (n = 17, controls). The former group was sampled the evening before the jump and 20 min after landing. Compared with controls, NGF levels increased 84% in prejump and 107% in postjump sampling. Our studies also showed that the increase of NGF levels preceded the increase of plasma cortisol and adrenocorticotropic hormone. No changes in the baseline levels of circulating interleukin 1 beta or tumor necrosis factor were found, suggesting that the increased levels of NGF were not correlated with change in these cytokines. Moreover, immunofluorescence analysis demonstrated that parachuting stress enhances the distribution of low-affinity p75LNGFR and high-affinity p140trkA NGF receptors in circulating peripheral blood mononuclear cells. These observations suggest that the release of NGF might be involved in the activation of cells of the immune system and is most probably associated with homeostatic adaptive mechanisms, as previously shown for stressed rodents
Increased plasma levels of substance P in vernal keratoconjunctivitis
No full textThe increase of nerve growth factor (NGF) plasma levels in vernal keratoconjunctivitis (VKC) patients has been demonstrated previously. Results of numerous studies in vitro and in vivo have shown that NGF modulates the synthesis of substance P (SP), a neuropeptide involved in the pathogenesis of human allergic diseases. In this study the involvement of SP in this allergic conjunctivitis is investigated, along with its relationship with NGF and other systemic and local markers of VKC
Daily serum and saliva BDNF levels correlate with morning-evening personalità type in women and are affected by light therapy
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