286 research outputs found
In vitro effects of cocaine on tunneling nanotube formation and extracellular vesicle release in glioblastoma cell cultures
The effects of cocaine (150 nM, 300 nM, and 150 μM) on human glioblastoma cell cultures were studied on tunneling nanotube formation (1-h cocaine treatment) and extracellular vesicle release (1-, 3-, and 8-h cocaine treatment). Cocaine significantly increased the number of tunneling nanotubes only at the lowest concentration used. The release of extracellular vesicles (mainly exosomes) into the medium was stimulated by cocaine at each concentration used with a maximum effect at the highest concentration tested (150 μM). Moreover, cocaine (150 nM) significantly increased the number of vesicles with 61-80 nm diameter while at concentrations of 300 nM and 150 μM, and the smaller vesicles (30-40 nm diameter) were significantly increased with a reduction of the larger vesicles (41-60 nm diameter). A time dependence in the release of extracellular vesicles was observed. In view of the proposed role of these novel intercellular communication modes in the glial-neuronal plasticity, it seems possible that they can participate in the processes leading to cocaine addiction. The molecular target/s involved in these cocaine effects could be specific molecular components of plasma membrane lipid rafts and/or cocaine-induced modifications in cytoplasmic lipid composition
Effectiveness of clozapine and olanzapine: a comparison in severe, psychotically ill patients
The aim of our study was to evaluate the effectivenessof clozapine and olanzapine in the treatment of schizophrenicpatients. Either clozapine or olanzapine signifcantly ameliorated positive symptoms, but only clozapine was effective in reducinganxiety and hallucinations, while olanzapine was more effective in reducing negative symptoms, such as mannerism and posturing, blunted affect and emotional withdrawal. Olanzapine-treated patients obtained significantly higher GAF scores than clozapine-treated patients and more frequently participated in rehabilitative programmes. In conclusio, olanzapine therapy has surprisingly been shown to be more effective than clozapine in improving social and working skills
The main actors involved in parasitization of Heliothis virescens larva
At the moment of parasitization by another insect, the host Heliothis larva is able to defend itself by the activation of humoral and cellular defenses characterized by unusual reactions of hemocytes in response to external stimuli. Here, we have combined light and electron microscopy, staining reactions, and immunocytochemical characterization to analyze the activation and deactivation of one of the most important immune responses involved in invertebrates defense, i.e., melanin production and deposition. The insect host/parasitoid system is a good model to study these events. The activated granulocytes of the host insect are a major repository of amyloid fibrils forming a lattice in the cell. Subsequently, the exocytosed amyloid lattice constitutes the template for melanin deposition in the hemocel. Furthermore, cross-talk between immune and neuroendocrine systems mediated by hormones, cytokines, and neuromodulators with the activation of stress-sensoring circuits to produce and release molecules such as adrenocorticotropin hormone, alpha melanocyte-stimulating hormone, and neutral endopeptidase occurs. Thus, parasitization promotes massive morphological and physiological modifications in the host insect hemocytes and mimics general stress conditions in which phenomena such as amyloid fibril formation, melanin polymerization, pro-inflammatory cytokine production, and activation of the adrenocorticotropin hormone system occur. These events observed in invertebrates are also reported in the literature for vertebrates, suggesting that this network of mechanisms and responses is maintained throughout evolution
Neural damage biomarkers during open carotid surgery versus endovascular approach
BACKGROUND:
Carotid endarterectomy (CEA) is the gold standard for treating severe carotid artery stenosis, whereas carotid artery stenting (CAS) represents an endovascular alternative. The objective of this study was to assess the potential neural damage following open or endovascular carotid surgery measured by peripheral blood concentration of 3 biomarkers: S100β, matrix metalloproteinase-9 (MMP-9), and d-dimer.
METHODS:
Data for this prospective investigation were obtained from the Carotid Markers study (January 2010-2011), which sought to measure the levels of specific biomarkers of neuronal damage and thrombosis on candidates to CEA or CAS presenting at the Department of Vascular Surgery of the Nuovo Ospedale S. Agostino Estense of Modena (Italy) at baseline and at 24 hr after surgery. Relevant medical comorbidities were noted.
RESULTS:
A total of 113 consecutive patients were enrolled in the study, 41 in the endarterectomy group and 72 in the endovascular group. The baseline levels of the studied biomarkers did not show any statistically significant difference between the groups with the exception of MMP-9, which showed higher concentrations in the endovascular group (median 731 vs. 401, P = 0.0007), while 24 hr after surgery the endarterectomy group featured significantly higher peripheral blood concentrations of MMP-9, S100β, and d-dimer. Conversely, no significant difference was detected in the endovascular group except the d-dimer level.
CONCLUSIONS:
Neural damage biomarkers demonstrated a substantial difference between open and endovascular carotid surgery, which, if performed in selected patients, may become a less invasive alternative to CEA
Microvesicle and tunneling nanotube mediated intercellular transfer of g-protein coupled receptors in cell cultures.
none12Recent evidence shows that cells exchange collections of signals via microvesicles (MVs) and tunneling nano-tubes (TNTs). In this paper we have investigated whether in cell cultures GPCRs can be transferred by means of MVs and TNTs from a source cell to target cells. Western blot, transmission electron microscopy and gene expression analyses demonstrate that A(2A) and D(2) receptors are present in released MVs. In order to further demonstrate the involvement of MVs in cell-to-cell communication we created two populations of cells (HEK293T and COS-7) transiently transfected with D(2)R-CFP or A(2A)R-YFP. These two types of cells were co-cultured, and FRET analysis demonstrated simultaneously positive cells to the D(2)R-CFP and A(2A)R-YFP. Fluorescence microscopy analysis also showed that GPCRs can move from one cell to another also by means of TNTs. Finally, recipient cells pre-incubated for 24 h with A(2A)R positive MVs were treated with the adenosine A(2A) receptor agonist CGS-21680. The significant increase in cAMP accumulation clearly demonstrated that A(2A)Rs were functionally competent in target cells. These findings demonstrate that A(2A) receptors capable of recognizing and decoding extracellular signals can be safely transferred via MVs from source to target cells.openM. Guescini; G. Leo; S. Genedani; C. Carone; F. Pederzoli; F. Ciruela; D. Guidolin; V. Stocchi; M. Mantuano; D.O. Borroto-Escuela; K. Fuxe; L.F. AgnatiGuescini, Michele; G., Leo; S., Genedani; C., Carone; F., Pederzoli; F., Ciruela; D., Guidolin; Stocchi, Vilberto; Mantuano, Michela; D. O., Borroto Escuela; K., Fuxe; L. F., Agnat
Systems proteomic analysis reveals that Clusterin and Tissue Inhibitor of Metalloproteinases 3 increase in leptomeningeal arteries affected by cerebral amyloid angiopathy
AIMS: Amyloid beta (Aβ) accumulation in the walls of leptomeningeal arteries as cerebral amyloid angiopathy (CAA) is a major feature of Alzheimer's disease. In this study, we used global quantitative proteomic analysis to examine the hypothesis that the leptomeningeal arteries derived from patients with CAA have a distinct endophenotypic profile compared to those from young and elderly controls.METHODS: Freshly dissected leptomeningeal arteries from the Newcastle Brain Tissue Resource and Edinburgh Sudden Death Brain Bank from seven elderly (82.9±7.5 years) females with severe capillary and arterial CAA, as well as seven elderly (88.3±8.6 years) and five young (45.4±3.9 years) females without CAA were used in this study. Arteries from four patients with CAA, two young and two elderly controls were individually analysed using quantitative proteomics. Key proteomic findings were then validated using immunohistochemistry.RESULTS: Bioinformatics interpretation of the results showed a significant enrichment of the immune response/classical complement and extracellular matrix remodelling pathways (p<0.05) in arteries affected by CAA vs. those from young and elderly controls. Clusterin (Apolipoprotein J) and tissue inhibitor of metalloproteinases-3 (TIMP3), validated using immunohistochemistry, were shown to co-localize with Aβ and to be upregulated in leptomeningeal arteries from CAA patients compared to young and elderly controls CONCLUSIONS: Global proteomic profiling of brain leptomeningeal arteries revealed that clusterin and TIMP3 increase in leptomeningeal arteries affected by CAA. We propose that clusterin and TIMP3 could facilitate perivascular clearance and may serve as novel candidate therapeutic targets for cerebral amyloid angiopathy. This article is protected by copyright. All rights reserved.</p
Cerebral ornithine decarboxylase levels following gestational exposure to cocaine
The pre- and postnatal developmental course of cerebral ornithine decarboxylase (ODC) has been studied in infant rats after treatment of pregnant dams with cocaine. Levels of cocaine attained in brains and serum of embryos were not initially increased over corresponding maternal values, but were more persistent. However, cocaine was not longer detectable in these tissues 4 days after administration. The cerebral ODC level of treated pups was initially depressed and subsequently elevated relative to control values. These changes were apparent at times when cocaine was not detected in the developing brain. Results indicate that a transient exposure to cocaine in utero may lead to prolonged developmental abnormality
ACTH-(11-24) antagonizes ACTH-(1-24)-induced behavioral syndrome
The possible involvement of the ACTH-(11-24) fragment on the stretchings, yawnings and penile erections induced by the intracerebroventricular injection of ACTH-(1-24) in rats, was studied. The results indicate that this C-terminal fragment is devoid of any behavioral activity, but inhibits the behavioral syndrome induced by ACTH-(1-24). This suggests that the fragment-(11-24) of the ACTH molecule may contain or represent an address sequence for brain ACTH receptors and may be involved in the termination of the behavioral response to melanocortins
Phentolamine inhibition of rat seminal vesicle response to dopaminemimetic drugs: α-adrenoceptor implication or lack of specificity?
ACTH and its Role in Immune-neuroendocrine Functions. A Comparative Study
Adrenocorticotropic hormone (ACTH) belongs to the melanocortine group of related peptides which share a common precursor, the pro-opiomelanocortin (POMC). Melanocortin expresses its functional effects by the stimulation of specific G-protein coupled receptors. To date, five receptor subtypes have been cloned. The POMC gene has been highly conserved during evolution, and ACTH has been found in different cells from invertebrates to vertebrates to vertebrates, including man. Witµ regards the immune system, the presence of melanocortin receptors and the production of ACTH have been reported in invertebrate and vertebrate immuno-competent cells. Among its various physiological effects, ATCH has been shown to play a central role in immmune responses, such as chemotaxis and phagocytosis, in lower and higher forms of life. Moreover, ACTH is a key actor in stress response, and the complex cascade of events observed in vertebrates is reproduced and concentrated in intvertebrate immurtocytes. On the basis of the present findings, ACTH should be considered an important immuno regulator, forming part of the complex mosaic of relationships between the immune and neuroendocrine system which appears to have been substantially maintained over the course of evolution.
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