848 research outputs found
Impaired Activation of CA3 Pyramidal Neurons in the Epileptic Hippocampus.
We employed in vitro and ex vivo imaging tools to characterize the function of limbic neuron networks in pilocarpine-treated and age-matched, nonepileptic control (NEC) rats. Pilocarpine-treated animals represent an established model of mesial temporal lobe epilepsy. Intrinsic optical signal (IOS) analysis of hippocampal-entorhinal cortex (EC) slices obtained from epileptic rats 3 wk after pilocarpine-induced status epilepticus (SE) revealed hyperexcitability in many limbic areas, but not in CA3 and medial EC layer III. By visualizing immunopositivity for FosB/DeltaFosB-related proteins which accumulate in the nuclei of neurons activated by seizures we found that: (1) 24 h after SE, FosB/DeltaFosB immunoreactivity was absent in medial EC layer III, but abundant in dentate gyrus, hippocampus proper (including CA3) and subiculum; (2) FosB/DeltaFosB levels progressively diminished 3 and 7 d after SE, whereas remaining elevated (p < 0.01) in subiculum; (3) FosB/DeltaFosB levels sharply increased 2 wk after SE (and remained elevated up to 3 wk) in dentate gyrus and in most of the other areas but not in CA3. A conspicuous neuronal damage was noticed in medial EC layer III, whereas hippocampus was more preserved. IOS analysis of the stimulus-induced responses in slices 3 wk after SE demonstrated that IOSs in CA3 were lower (p < 0.05) than in NEC slices following dentate gyrus stimulation, but not when stimuli were delivered in CA3. These findings indicate that CA3 networks are hypoactive in comparison with other epileptic limbic areas. We propose that this feature may affect the ability of hippocampal outputs to control epileptiform synchronization in EC
Can We Rely on AGNP Therapeutic Targets also for LAI Antipsychotics?
The updated AGNP Consensus Guidelines for Therapeutic Drug Monitoring (TDM) in Neuropsychopharmacology recently published in the journal have reinforced the key role of TDM to individualize psychoparmacological therapies in clinical practice. However, we believe, that these guidelines have missed the important opportunity to face with, and to provide useful information on, the emerging issue of long-acting injectable formulations of atypical antipsychotics. Specific therapeutic ranges also for these formulations should be included in the next AGNP guidelines
Effect of crystallization kinetics on the properties of spray dried microparticles
<p>A droplet chain technique was used to study the influence of the crystallization process on the morphology of spray dried microparticles. A piezoceramic dispenser produced a chain of monodisperse solution droplets with an initial diameter in the range of 60–80 µm. Aqueous solutions of sodium nitrate were prepared in concentrations ranging from 5 mg/ml to 5⋅10<sup>−5</sup> mg/ml. The solution droplets were injected into a laminar flow with gas temperatures varying from 25 to 150°C, affecting the droplet temperature and the evaporation rate, accordingly. Dried particles with diameters between 0.3 and 18 µm were collected. The properties of the collected microparticles were studied and correlated with a particle formation model which predicted the onset of saturation and crystallization. The model accounted for the dependence of the diffusion coefficient of sodium nitrate in water on droplet viscosity. The viscosity trend for sodium nitrate solutions was determined by studying the relaxation time observed during coalescence of two aqueous sodium nitrate droplets levitated in optical tweezers. The combination of theoretical derivations and experimental results showed that longer time available for crystallization correlates with larger crystal size and higher degrees of crystallinity in the final microparticles.</p> <p>© 2016 American Association for Aerosol Research</p
Large-scale, high-resolution electrophysiological imaging of field potentials in brain slices with microelectronic multielectrode arrays
Multielectrode arrays (MEAs) are extensively used for electrophysiological studies on brain slices, but the spatial resolution and field of recording of conventional arrays are limited by the low number of electrodes available. Here, we present a large-scale array recording simultaneously from 4096 electrodes used to study propagating spontaneous and evoked network activity in acute murine cortico-hippocampal brain slices at unprecedented spatial and temporal resolution. We demonstrate that multiple chemically induced epileptiform episodes in the mouse cortex and hippocampus can be classified according to their spatio-temporal dynamics. Additionally, the large-scale and high-density features of our recording system enable the topological localization and quantification of the effects of antiepileptic drugs in local neuronal microcircuits, based on the distinct field potential propagation patterns. This novel high-resolution approach paves the way to detailed electrophysiological studies in brain circuits spanning spatial scales from single neurons up to the entire slice network
Nightmare disorder and REM sleep behavior disorder in inflammatory arthritis: Possibility beyond neurodegeneration.
OBJECTIVES:To investigate the prevalence of REM sleep behavior disorder (RBD) in patients with inflammatory arthritis (IA) to ascertain if RBD could be an internal red flag signaling a fluctuating state of inflammation based on the theory of "protoconsciousness".
MATERIALS & METHODS:One hundred and three patients with a confirmed diagnosis of IA were consecutively recruited. The patients underwent general (IA activity, functional status, laboratory tests) and neurological evaluations. A neurologist investigated RBD and REM sleep parasomnias in a semi-structured interview. Sleep quality was assessed with the Pittsburgh Sleep Quality Index, while the risk of obstructive sleep apnea syndrome (OSAS) was evaluated with the Berlin questionnaire. Beck Depression Inventory II and State-Trait Anxiety Inventory investigated depression and anxiety.
RESULTS:Patients had a mean age of 53.7 ± 14.6 years, 65% were women; 57.3% were in a clinically active phase of IA. Two women fulfilled ICSD-3 criteria for RBD appearing 11 years after and 20 years before IA onset respectively. 31 patients scored positive for nightmare disorder (ND), 8 for recurrent isolated sleep paralysis. 65 (63.1%) patients reported poor sleep quality and 25 (24.3%) resulted at high risk for OSAS. 32 (31.0%) patients scored positively for depression or anxiety.
CONCLUSIONS:The prevalence of RBD in patients with IA did not differ from that in the general population, whereas ND presented a 2-fold increased prevalence. Whether RBD can be considered a red flag signaling an internal danger remains an open question, while ND may be a new player in this intriguing relation
Acute pancreatitis secondary to non-functioning pancreatic neuroendocrine tumor: uncommon clinical presentation. Clinical case and review of literature
I tumori neuroendocrini del pancreas (PNET) sono rari, e rappresentano <5% di tutte le neoplasie pancreatiche, suddivisi in PNET funzionanti con secrezione ormonale responsabile di sintomi specifici e PNET non funzionanti (nf-PNET) generalmente di diagnosi tardiva per la comparsa di metastasi o manifestazioni cliniche per effetti compressivi. L’approccio chirurgico è il trattamento di scelta per PNETs funzionanti, non-funzionanti di diametro superiore a 2 cm o sintomatici per disturbi da compressione. Osservazione personale. Donna di 76 anni ricoverata presso la UOC-Università-Chirurgia Ospedale “A. Fiorini” di Terracina per nausea e dolore ai quadranti addominali superiori con irradiazione dorso-lombare, insorti dopo un pasto serale. Dopo gli esami ematochimici e le indagini strumentali, è stata fatta la diagnosi di pancreatite acuta severa. Gli US convenzionali, CCT, CE-MRI ed EUS hanno mostrato una lesione di 2,8 cm di diametro nella giunzione testa-corpo del pancreas. L’esame citologico FNA non ha rilevato la presenza di cellule pancreatiche atipiche. La scintigrafia total body con Octreoscan® ha documentato un’area di ipercaptazione patologica situata in corrispondenza della neoformazione. La paziente è stata sottoposta a spleno-pancreasectomia corpo-coda. L’esame istologico ha dimostrato un nf-PNET di grado intermedio (G2) stenosante il vena lienale e stenosante il dotto di Wirsung, con pancreatite perilesionale. L’immunoistochimica ha mostrato un immunofenotipo positivo per CAM5.2, sinaptofisina (> 95%) e cromogranina (60%), con espressione di somatostatina intratumorale negativa. CONCLUSIONE: Sebbene raramente un nf-PNETS può essere la causa di grave pancreatite acuta non biliare da compressione del sistema duttale pancreatico. Nei casi in cui la PET / CT68Ga non può essere eseguita, la scintigrafia total body con Octreoscan® rimane il metodo più utilizzato per la diagnosi dei PNET e l’identificazione delle eventuali lesioni extra-pancreatiche. La cromogranina e la sinaptofisina sono confermate come marcatori specifici del differenziamento neuroendocrino.BACKGROUND: Pancreatic neuroendocrine tumors (PNETs) are uncommon, representing <5% of all pancreatic neoplasms, divided into functioning PNETs with secreted hormone cause of specific symptoms, and non-functioning PNETs (nf- PNETs) characterized by delayed diagnosis with metastases and clinical manifestations of compressive effects. Surgical approach is recommended for functioning and nf-PNETs >2 cm in diameter. CASE REPORT: A 76-year-old woman was admitted to the UOC-University-Surgery Hospital "A. Fiorini" in Terracina for nausea and pain in the upper abdominal quadrants with dorso-lumbar irradiation, arising after the evening meal. After the haematochemistry tests and the instrumental investigations, the diagnosis of acute, severe halitiasic pancreatitis was made. Conventional US, CCT, CE-MRI and EUS showed a 2.8cm diameter lesion in the head-body junction of the pancreas. FNA-cytological examination did not found the presence of atypical pancreatic cells. Total-body scintigraphy with Octreoscan® documented a pathological hypercaptation area located in correspondence with the neoformation. The patient underwent a body-tail spleno-pancreatectomy. The histological examination showed an intermediate grade (G2) nf-PNET infiltrating the lienal vein and stenosing the Wirsung duct, with perilesional pancreatitis. Immunohistochemistry showed CAM 5.2, Synaptophysin (>95%) and Chromogranin (60%) positive immunophenotype, with negative intratumoral Somatostatin expression. CONCLUSION: Although rarely, nf-PNETS may be the cause of severe non-biliary acute pancreatitis from pancreatic ductal system compression. In cases where PET/CT68Ga cannot be performed, total-body scintigraphy with Octreoscan® remains the most widely used method for the diagnosis of PNETs and the identification of extra-pancreatic lesions. Chromogranin and Synaptophysin are confirmed as specific markers of neuroendocrine differentiation. KEY WORDS: Acute pancreatitis, Chromogranin, Pancreatic neuroendocrine tumor, Synaptophysin, Somatostatin
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