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1.
Clin Ter ; 172(5): 427-434, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34625774

RESUMO

BACKGROUND: Adequate training in tobacco, nicotine dependence and treatment is lacking in Medical School education. With the rise in popularity of electronic alternatives to cigarettes, future physicians should also be provided with the more recent scientific evidence on these products during their undergraduate studies. We introduced an e-learning course for Medical School students and assessed its effec-tiveness of increasing knowledge on these topics. METHODS: We developed 16 didactic modules divided in 3 courses: tobacco dependence (TDI), treating tobacco dependence (TDII) and electronic products and tobacco control (TDIII). The course was offered to 4th, 5th, and 6th year Medical School students in Italy. To assess learning outcomes, we examined the pre- to post- changes in knowledge scores associated with each course. Paired and independent samples t-tests were performed overall, and among smokers and non-smokers separately. RESULTS: A total of 1318 students completed at least one of the courses; 21% were self-reported smokers. A significant increase in knowledge was observed at the end of TDI (pre-course: 52.1±15.9, post-course: 79.9±13.5, p<0.001), TDII (pre-course: 52.5±13.0, post-course: 66.5±12.0, p<0.001) and TDIII (pre-course: 52.2±15.3, post-course: 76.1±17.7, p<0.001). Smokers showed significantly lower improvements compared to non-smokers. CONCLUSIONS: The e-learning course was effective in increasing knowledge about tobacco dependence, treatments, and electronic ni-cotine products in advanced medical students. Given the fundamental role for healthcare practitioners in encouraging and assisting people in quitting smoking, e-learning may be a useful tool in providing up-to-date and standardized training in the area during Medical School.


Assuntos
Instrução por Computador , Sistemas Eletrônicos de Liberação de Nicotina , Estudantes de Medicina , Tabagismo , Temperatura Alta , Humanos , Faculdades de Medicina , Tabagismo/terapia
2.
Pharmacol Res ; 170: 105691, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34044128

RESUMO

Interkingdom communication between bacteria and host organisms is one of the most interesting research topics in biology. Quorum sensing molecules produced by Gram-negative bacteria, such as acylated homoserine lactones and quinolones, have been shown to interact with host cell receptors, stimulating innate immunity and bacterial clearance. To our knowledge, there is no evidence that these molecules influence CNS function. Here, we have found that low micromolar concentrations of the Pseudomonas aeruginosa quorum sensing autoinducer, 2-heptyl-3-hydroxy-4-quinolone (PQS), inhibited polyphosphoinositide hydrolysis in mouse brain slices, whereas four selected acylated homoserine lactones were inactive. PQS also inhibited forskolin-stimulated cAMP formation in brain slices. We therefore focused on PQS in our study. Biochemical effects of PQS were not mediated by the bitter taste receptors, T2R4 and T2R16. Interestingly, submicromolar concentrations of PQS could be detected in the serum and brain tissue of adult mice under normal conditions. Levels increased in five selected brain regions after single i.p. injection of PQS (10 mg/kg), peaked after 15 min, and returned back to normal between 1 and 4 h. Systemically administered PQS reduced spontaneous locomotor activity, increased the immobility time in the forced swim test, and largely attenuated motor response to the psychostimulant, methamphetamine. These findings offer the first demonstration that a quorum sensing molecule specifically produced by Pseudomonas aeruginosa is centrally active and influences cell signaling and behavior. Quorum sensing autoinducers might represent new interkingdom signaling molecules between ecological communities of commensal, symbiotic, and pathogenic microorganisms and the host CNS.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , AMP Cíclico/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Pseudomonas aeruginosa/metabolismo , Quinolonas/farmacologia , Percepção de Quorum , Transdução de Sinais/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Interações Hospedeiro-Patógeno , Hidrólise , Técnicas In Vitro , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Teste do Labirinto Aquático de Morris/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Quinolonas/metabolismo
3.
Rev. argent. reumatolg. (En línea) ; 30(3): 22-25, 2019. tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1117705

RESUMO

El FIHOA fue desarrollado para evaluar la capacidad funcional de pacientes con OA de manos. Objetivo: Validar FIHOA en pacientes con AR. Métodos: Estudio analítico, observacional prospectivo de corte transversal. Se incluyeron pacientes consecutivos con diagnóstico de AR (ACR/EULAR 2010). Se consignaron datos demográficos y características de la enfermedad. Todos los pacientes completaron los siguientes cuestionarios autoadministrados: FIHOA, HAQ-A, HAQ-UP-A y Quick DASH. En un subgrupo de pacientes, una terapista ocupacional valoró la capacidad funcional de la mano por medio del test de SODA-A. Se evaluó la reproducibilidad de FIHOA. Análisis estadístico: Estadística descriptiva. Confiabilidad con test de Cronbach. Validez de constructo con correlación de Spearman. Reproducibilidad test re-test. Modelo de regresión lineal. Resultados: Se incluyeron 100 pacientes. La prueba alfa de Cronbach fue de 0,94. No se evidenciaron preguntas redundantes. El FIHOA mostró excelente correlación con HAQ-A (r=0,89); HAQ-UP-A (r=0,89); Quick DASH (r=0,90) y SODA-A (r=-0,80); y buena correlación con DAS28-ERS (r=0,65), y con otros parámetros de la enfermedad. La reproducibilidad fue 0,73. La regresión lineal múltiple mostró como principal determinante del FIHOA a la presencia de rigidez matinal seguida por el uso de corticoides y el EVA general de pacientes. Conclusión: El FIHOA resultó ser confiable, válido y reproducible en pacientes con AR


FIHOA was developed to evaluate the functional capacity of patients with OA hands. Objetive: To validate FIHOA in patients with RA. Methods: Analytical, observational, prospective cross-sectional study. Consecutive patients with diagnosis of RA (ACR/EULAR 2010) were included. Demographic and RA characteristics were recorded. Patients completed the following self-administered questionnaires: FIHOA, HAQ-A, HAQ-UP-A and Quick DASH. For a patient subgroup, an occupational therapist performed an objective evaluation of the functional capacity of the hands using the SODA-A. Reproducibility was assessed. Statistical analysis: Descriptive statistics. Reliability with the Cronbach test. Construct validity with Spearman correlation. Reproducibility with test-retest reliability. Linear regression model. Results: One hundred patients were included. Cronbach's alpha test was 0.94. There were no redundant questions. FIHOA showed an excellent correlation with HAQ-A (r=0.89); HAQUP-A (r=0.89); Quick DASH (r=0.90) and SODA-A (r=-0.80); and a good correlation with DAS28- ERS (r=0.65) and with other disease parameters. Questionnaire reproducibility was 0.73. A multiple linear regression showed morning stiffness as the main determinant of FIHOA, followed by glucocorticoid use and patient global assessment. Conclusion: FIHOA was found to be reliable, valid and reproducible in patients with RA


Assuntos
Osteoartrite , Artrite Reumatoide , Mãos
4.
Osteoporos Int ; 28(6): 1915-1923, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28243706

RESUMO

This study deals with the role of texture analysis as a predictive factor of radiation-induced insufficiency fractures in patients undergoing pelvic radiation. INTRODUCTION: This study aims to assess the texture analysis (TA) of computed tomography (CT) simulation scans as a predictive factor of insufficiency fractures (IFs) in patients with pelvic malignancies undergoing radiation therapy (RT). METHODS: We performed an analysis of patients undergoing pelvic RT from January 2010 to December 2014, 24 of whom had developed pelvic bone IFs. We analyzed CT-simulation images using ImageJ macro software and selected two regions of interest (ROIs), which are L5 body and the femoral head. TA parameters included mean (m), standard deviation (SD), skewness (sk), kurtosis (k), entropy (e), and uniformity (u). The IFs patients were compared (1:2 ratio) with controlled patients who had not developed IFs and matched for sex, age, menopausal status, type of tumor, use of chemotherapy, and RT dose. A reliability test of intra- and inter-reader ROI TA reproducibility with the intra-class correlation coefficient (ICC) was performed. Univariate and multivariate analyses (logistic regression) were applied for TA parameters observed both in the IFs and the controlled groups. RESULTS: Inter- and intra-reader ROI TA was highly reproducible (ICC > 0.90). Significant TA parameters on paired t test included L5 m (p = 0.001), SD (p = 0.002), k (p = 0.006), e (p = 0.004), and u (p = 0.015) and femoral head m (p < 0.001) and SD (p = 0.001), whereas on logistic regression analysis, L5 e (p = 0.003) and u (p = 0.010) and femoral head m (p = 0.027), SD (p = 0.015), and sex (p = 0.044). CONCLUSIONS: In our experience, bone CT TA could be correlated to the risk of radiation-induced IFs. Studies on a large patient series and methodological refinements are warranted.


Assuntos
Fraturas de Estresse/etiologia , Ossos Pélvicos/lesões , Lesões por Radiação/etiologia , Radioterapia de Alta Energia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Colo do Fêmur/diagnóstico por imagem , Fraturas de Estresse/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Ossos Pélvicos/efeitos da radiação , Neoplasias Pélvicas/radioterapia , Valor Preditivo dos Testes , Lesões por Radiação/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Dosagem Radioterapêutica , Radioterapia de Alta Energia/métodos , Medição de Risco/métodos , Tomografia Computadorizada por Raios X/métodos
5.
Pharmacol Res ; 119: 12-19, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28137639

RESUMO

Acid-sensing ion channels (ASICs), members of the degenerin/epithelial Na+ channel superfamily, are widely distributed in the mammalian nervous system. ASIC1a is highly permeable to Ca2+ and are thought to be important in a variety of physiological processes, including synaptic plasticity, learning and memory. To further understand the role of ASIC1a in synaptic transmission and plasticity, we investigated metabotropic glutamate (mGlu) receptor-dependent long-term depression (LTD) in the hippocampus. We found that ASIC1a channels mediate a component of LTD in P30-40 animals, since the ASIC1a selective blocker psalmotoxin-1 (PcTx1) reduced the magnitude of LTD induced by application of the group I mGlu receptor agonist (S)-3,5-Dihydroxyphenylglycine (DHPG) or induced by paired-pulse low frequency stimulation (PP-LFS). Conversely, PcTx1 did not affect LTD in P13-18 animals. We also provide evidence that ASIC1a is involved in group I mGlu receptor-induced increase in action potential firing. However, blockade of ASIC1a did not affect DHPG-induced polyphosphoinositide hydrolysis, suggesting the involvement of some other molecular partners in the functional crosstalk between ASIC1a and group I mGlu receptors. Notably, PcTx1 was able to prevent the increase in GluA1 S845 phosphorylation at the post-synaptic membrane induced by group I mGlu receptor activation. These findings suggest a novel function of ASIC1a channels in the regulation of group I mGlu receptor synaptic plasticity and intrinsic excitability.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Hipocampo/fisiologia , Depressão Sináptica de Longo Prazo , Receptores de Glutamato Metabotrópico/metabolismo , Potenciais de Ação , Animais , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Células Piramidais/fisiologia
6.
Neurosci Lett ; 630: 23-29, 2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27412236

RESUMO

Mutations in parkin cause autosomal recessive Parkinsonism and mitochondrial defects. A recent drug screen identified a class of steroid-like hydrophobic compounds able to rescue mitochondrial function in parkin-mutant fibroblasts. Whilst these possess therapeutic potential, the size and high hydrophobicity of some may limit their ability to penetrate the blood-brain barrier from systemic circulation, something that could be improved by novel drug formulations. In the present study, the steroid-like compounds Ursolic Acid (UA) and Ursocholanic Acid (UCA) were successfully encapsulated within nanoscopic polymersomes formed by poly(2-(methacryloyloxy)ethyl phosphorylcholine)-poly(2-di-isopropylamino)ethyl methacrylate) (PMPC-PDPA) and separated into spherical and tubular morphologies to assess the effects of nanoparticle mediated delivery on drug efficacy. Following incubation with either morphology, parkin-mutant fibroblasts demonstrated time and concentration dependent increases in intracellular ATP levels, resembling those resulting from treatment with nascent UA and UCA formulated in 0.1% DMSO, as used in the original drug screen. Empty PMPC-PDPA polymersomes did not alter physiological measures related to mitochondrial function or induce cytotoxicity. In combination with other techniques such as ligand functionalisation, PMPC-PDPA nanoparticles of well-defined morphology may prove a promising platform for tailoring the pharmacokinetic profile and organ specific bio-distribution of highly hydrophobic compounds.


Assuntos
Ácidos Cólicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Nanocápsulas/administração & dosagem , Fosforilcolina/análogos & derivados , Ácidos Polimetacrílicos/farmacologia , Triterpenos/farmacologia , Ubiquitina-Proteína Ligases/genética , Trifosfato de Adenosina/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Mitocôndrias/metabolismo , Mutação , Nanocápsulas/toxicidade , Nanocápsulas/ultraestrutura , Fosforilcolina/farmacologia , Fosforilcolina/toxicidade , Ácidos Polimetacrílicos/toxicidade , Ácido Ursólico
7.
Dis Esophagus ; 28(4): 394-403, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24708360

RESUMO

Human epidermal growth factor receptor 2 (HER2) is involved in the malignant progression of several human cancers, including esophageal adenocarcinoma (EAC). The purpose of this study was to evaluate HER2 overexpression and to explore the feasibility of confocal laser endomicroscopy for in vivo molecular imaging of HER2 status in an animal model of Barrett's-related EAC. Rats underwent esophagojejunostomy with gastric preservation. At 30 weeks post-surgery, the esophagus of 46 rats was studied; endoscopic and histological findings were correlated with HER2 immunofluorescence on excised biopsies and gross specimens. At this age, 23/46 rats developed Barrett's esophagus (BE), and 6/46 had cancer (four EAC and two squamous cell carcinomas). A significant overexpression of HER2 was observed in esophageal adenocarcinoma compared with normal squamous esophagus (9.4-fold) and BE (6.0-fold). AKT and its phosphorylated form were also overexpressed in cancer areas. Molecular imaging was performed at 80 weeks post-surgery in four rats after tail injection of fluorescent-labeled anti-HER2 antibody. At this age, 3/4 rats developed advance adenocarcinoma and showed in vivo overexpression of HER2 by molecular confocal laser endomicroscopy with heterogeneous distribution within cancer; no HER2 signal was observed in normal or Barrett's tissues. Therefore, HER2 overexpression is a typical feature of the surgical induced model of EAC that can be easily quantified in vivo using an innovative mini-invasive approach including confocal endomicroscopy; this approach may avoid limits of histological evaluation of HER2 status on 'blinded' biopsies.


Assuntos
Adenocarcinoma/metabolismo , Esôfago de Barrett/metabolismo , Neoplasias Esofágicas/metabolismo , Imagem Molecular/métodos , Adenocarcinoma/induzido quimicamente , Animais , Esôfago de Barrett/complicações , Biópsia , Carcinoma de Células Escamosas/metabolismo , Modelos Animais de Doenças , Endoscopia , Neoplasias Esofágicas/induzido quimicamente , Imunofluorescência , Microscopia Intravital/métodos , Microscopia Confocal/métodos , Ratos , Ratos Sprague-Dawley , Receptor ErbB-2 , Coloração e Rotulagem
8.
G Ital Nefrol ; 31(1)2014.
Artigo em Italiano | MEDLINE | ID: mdl-24671839

RESUMO

In order to optimize the use of ultrasound in the characterization of cystic or nodular lesions, the incidence of simple cysts in the general population, their growth and evolution is discussed considering some follow-up studies. After studying the typical sonographic criteria of simple cyst, we describe the sonographic features of cancer and the incidence of various types of tumors. In such cases radiological evaluations are required and the Bosniak classification is useful in the clinical choice of waiting, more detailed diagnosis or excision of the lesion. The use of the radiological means will decrease when EcocolorDoppler with contrast is widely available. Nevertheless, this technique has already found its way into peculiar fields and in certain cases, it has a higher sensitivity compared to TAC with contrast medium.


Assuntos
Doenças Renais Císticas/diagnóstico por imagem , Feminino , Humanos , Masculino , Ultrassonografia
9.
Cell Death Differ ; 20(3): 396-407, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23175182

RESUMO

Drug treatment of malignant gliomas is limited by the intrinsic resistance of glioma stem cells (GSCs) to chemotherapy. GSCs isolated from human glioblastoma multiforme (GBM) expressed metabotropic glutamate receptors (mGlu3 receptors). The DNA-alkylating agent, temozolomide, killed GSCs only if mGlu3 receptors were knocked down or pharmacologically inhibited. In contrast, mGlu3 receptor blockade did not affect the action of paclitaxel, etoposide, cis-platinum, and irinotecan. mGlu3 receptor blockade enabled temozolomide toxicity by inhibiting a phosphatidylinositol-3-kinase/nuclear factor-κB pathway that supports the expression of O(6)-methylguanine-DNA methyltransferase (MGMT), an enzyme that confers resistance against DNA-alkylating agents. In mice implanted with GSCs into the brain, temozolomide combined with mGlu3 receptor blockade substantially reduced tumor growth. Finally, 87 patients with GBM undergoing surgery followed by adjuvant chemotherapy with temozolomide survived for longer time if tumor cells expressed low levels of mGlu3 receptors. In addition, the methylation state of the MGMT gene promoter in tumor extracts influenced survival only in those patients with low expression of mGlu3 receptors in the tumor. These data encourage the use of mGlu3 receptor antagonists as add-on drugs in the treatment of GBM, and suggest that the transcript of mGlu3 receptors should be measured in tumor specimens for a correct prediction of patients' survival in response to temozolomide treatment.


Assuntos
Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Aminoácidos/toxicidade , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Quimioterapia Adjuvante , Terapia Combinada , Metilação de DNA/efeitos dos fármacos , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/mortalidade , Humanos , Camundongos , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/citologia , O(6)-Metilguanina-DNA Metiltransferase/genética , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Receptores de Glutamato Metabotrópico/genética , Transdução de Sinais , Taxa de Sobrevida , Temozolomida , Transplante Heterólogo , Células Tumorais Cultivadas , Xantenos/toxicidade
11.
J Cardiovasc Surg (Torino) ; 53(2): 187-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22456641

RESUMO

AIM: The aim of this study was to evaluate early and follow-up results of below-knee bypasses performed with a bioactive heparin-treated ePTFE graft in patients with peripheral arterial obstructive disease (PAOD) in a multicentric retrospective registry involving seven Italian vascular centers and to compare them with those obtained in patients operated on with autologous saphenous vein (ASV) in the same centres in the same period of time. METHODS: Over a nine-year period, ending in 2010, a heparin bonded prosthetic graft (Propaten Gore-Tex, W.L. Gore & Associates Inc, Flagstaff, AZ, USA) was implanted in 556 patients undergoing below-knee revascularization for PAOD (HePTFE group). In the same period of time 394 below-knee bypasses with ipsilateral ASV were performed (ASV group). Data concerning these interventions were retrospectively collected in a multicenter registry with a dedicated database. Early (<30 days) results were analyzed in terms of graft patency, major amputation rates and mortality. Follow-up results were analyzed in terms of primary and secondary graft patency, limb salvage and survival. RESULTS: Among patients of HePTFE group, 413 had critical limb ischemia (74%); the corresponding figure for ASV group was 84% (332 interventions, P<0.001). Eighty-nine patients in HePTFE group (16%) and 207 patients in ASV group (52.5%; P<0.001) had distal tibial anastomosis. Patients in HePTFE group had more frequently adjunctive procedures performed at distal anastomotic sites in order to improve run-off status. Thirty-day death rate was 1.9% in HePTFE group and 0.5% in ASV group (P=0.08). The rates of perioperative thromboses and amputations were 6% and 3.5% in HePTFE group, and 5% and 1.7% in ASV group, without significant differences between the two groups. Mean duration of follow-up was 28.5±22.1 months; 921 patients (97%) had at least one postoperative clinical and ultrasonographic control. Estimated 48-month survival rates were 81% in HePTFE group and 74% in ASV group (P=0.7, log rank 0.1). Primary patency rate at 48 months was significantly better in ASV group (61%) than in HePTFE group (44.5%; P=0.004, log rank 8.1). The rates of secondary patency at 48 months were 57% in HePTFE group and 67.5% in ASV group (P=0.1, log rank 1.9); the corresponding values in terms of limb salvage in patients with critical limb ischemia were 77% and 79.5% (P=0.3, log rank 0.9), respectively. CONCLUSION: Data from this large, retrospective registry confirmed that the indexed heparin-bonded ePTFE graft provides satisfactory early and mid-term results in patients undergoing surgical below-knee revascularization. While autologous saphenous vein maintains its superiority in terms of primary patency, secondary patency and limb salvage rates are comparable.


Assuntos
Arteriopatias Oclusivas/cirurgia , Prótese Vascular , Artéria Femoral/cirurgia , Heparina/farmacologia , Politetrafluoretileno , Artéria Poplítea/cirurgia , Veia Safena/transplante , Idoso , Angiografia , Anticoagulantes/farmacologia , Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/fisiopatologia , Materiais Revestidos Biocompatíveis , Feminino , Artéria Femoral/fisiopatologia , Seguimentos , Humanos , Itália , Masculino , Desenho de Prótese , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Grau de Desobstrução Vascular
12.
Mol Pharmacol ; 81(5): 643-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22311707

RESUMO

Cinnabarinic acid is an endogenous metabolite of the kynurenine pathway that meets the structural requirements to interact with glutamate receptors. We found that cinnabarinic acid acts as a partial agonist of type 4 metabotropic glutamate (mGlu4) receptors, with no activity at other mGlu receptor subtypes. We also tested the activity of cinnabarinic acid on native mGlu4 receptors by examining 1) the inhibition of cAMP formation in cultured cerebellar granule cells; 2) protection against excitotoxic neuronal death in mixed cultures of cortical cells; and 3) protection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity in mice after local infusion into the external globus pallidus. In all these models, cinnabarinic acid behaved similarly to conventional mGlu4 receptor agonists, and, at least in cultured neurons, the action of low concentrations of cinnabarinic acid was largely attenuated by genetic deletion of mGlu4 receptors. However, high concentrations of cinnabarinic acid were still active in the absence of mGlu4 receptors, suggesting that the compound may have off-target effects. Mutagenesis and molecular modeling experiments showed that cinnabarinic acid acts as an orthosteric agonist interacting with residues of the glutamate binding pocket of mGlu4. Accordingly, cinnabarinic acid did not activate truncated mGlu4 receptors lacking the N-terminal Venus-flytrap domain, as opposed to the mGlu4 receptor enhancer, N-phenyl-7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxamide (PHCCC). Finally, we could detect endogenous cinnabarinic acid in brain tissue and peripheral organs by high-performance liquid chromatography-tandem mass spectrometry analysis. Levels increased substantially during inflammation induced by lipopolysaccharide. We conclude that cinnabarinic acid is a novel endogenous orthosteric agonist of mGlu4 receptors endowed with neuroprotective activity.


Assuntos
Cinurenina/metabolismo , Oxazinas/farmacologia , Receptores de Glutamato Metabotrópico/agonistas , Animais , Células Cultivadas , AMP Cíclico/biossíntese , Ácido Glutâmico/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Oxazinas/análise , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato Metabotrópico/fisiologia
13.
Dis Esophagus ; 25(3): 263-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21883657

RESUMO

The programmed cell death 4 (PDCD4) tumor suppressor is down-regulated in several malignancies, and the (subcellular) expression of its protein product is modulated by both oncomiR miR-21 and protein kinase B (Akt). PDCD4 and activated Akt (phosphorylated Akt [pAkt]) expression were assessed immunohistochemically in 53 tissue samples obtained from 25 endoscopic esophageal mucosal resections performed for squamous intraepithelial neoplasia (IEN) or squamous intramucosal carcinoma (IM-SSC). In total, 33 IEN (low-grade = 15; high-grade = 15) and 20 IM-SSC specimens were considered; 50 additional tissue samples of histologically proven normal esophageal mucosa were considered as normal controls. To further validate the results achieved, miR-21 expression (as assessed by quantitative real-time polymerase chain reaction and in situ hybridization) was tested in another series of 15 normal esophageal tissue samples, 15 high-grade IEN, and 15 IM-SCCs. Normal suprabasal squamous epithelial layers consistently featured strong PDCD4 nuclear immunostaining, which was significantly lower (P < 0.001) in IEN (both low-and high-grade) and in IM-SSC. Conversely, pAkt and miR-21 expression was significantly up-regulated in the whole spectrum of preneoplastic/neoplastic lesions considered. PDCD4 down-regulation, as assessed by immunohistochemistry, is a reliable biomarker of early-stage squamous cell esophageal neoplasia, providing additional information in the histological assessment of these lesions.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma in Situ/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a RNA/metabolismo , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , Núcleo Celular/metabolismo , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Regulação para Baixo , Neoplasias Esofágicas/patologia , Humanos , Imuno-Histoquímica , Estudos Retrospectivos , Estatísticas não Paramétricas
14.
Neuropharmacology ; 60(7-8): 1281-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21277877

RESUMO

Eight-month old WAG/Rij rats, which developed spontaneous occurring absence seizures, showed a reduced function of mGlu1 metabotropic glutamate receptors in the thalamus, as assessed by in vivo measurements of DHPG-stimulated polyphosphoinositide hydrolysis, in the presence of the mGlu5 antagonist MPEP as compared to age-matched non-epileptic control rats. These symptomatic 8-month old WAG/Rij rats also showed lower levels of thalamic mGlu1α receptors than age-matched controls and 2-month old (pre-symptomatic) WAG/Rij rats, as detected by immunoblotting. Immunohistochemical and in situ hybridization analysis indicated that the reduced expression of mGlu1 receptors found in symptomatic WAG/Rij rats was confined to an area of the thalamus that excluded the ventroposterolateral nucleus. No mGlu1 receptor mRNA was detected in the reticular thalamic nucleus. Pharmacological manipulation of mGlu1 receptors had a strong impact on absence seizures in WAG/Rij rats. Systemic treatment with the mGlu1 receptor enhancer SYN119, corresponding to compound RO0711401, reduced spontaneous spike and wave discharges spike-wave discharges (SWDs) in epileptic rats. Subcutaneous doses of 10 mg/kg of SYN119 only reduced the incidence of SWDs, whereas higher doses (30 mg/kg) also reduced the mean duration of SWDs. In contrast, treatment with the non-competitive mGlu1 receptor antagonist, JNJ16259685 (2.5 and 5 mg/kg, i.p.) increased the incidence of SWDs. These data suggest that absence epilepsy might be associated with a reduction of mGlu1 receptors in the thalamus, and that compounds that amplify the activity of mGlu1 receptors might be developed as novel anti-absence drugs. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.


Assuntos
Epilepsia Tipo Ausência/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Regulação Alostérica , Animais , Ciprofloxacina/análogos & derivados , Ciprofloxacina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Epilepsia Tipo Ausência/tratamento farmacológico , Epilepsia Tipo Ausência/genética , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Quinolinas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos , Receptores de Glutamato Metabotrópico/genética , Transdução de Sinais/efeitos dos fármacos , Núcleos Talâmicos/metabolismo , Núcleos Talâmicos/fisiopatologia , Tálamo/metabolismo , Tálamo/fisiopatologia
15.
Mol Pharmacol ; 76(2): 379-87, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19439499

RESUMO

The interaction between 5-hydroxytryptamine(2A) (5-HT(2A)) serotonin receptors and metabotropic glutamate (mGlu) 2/3 receptors underlies the antipsychotic activity of mGlu2/3 receptor agonists in experimental animals and humans. The molecular nature of this interaction is only partially known. We here report for the first time that pharmacological activation of mGlu2/3 receptors attenuates the stimulation of polyphosphoinositide (PI) hydrolysis mediated by 5-HT(2A) receptors in the frontal cortex of living mice. Mice were injected intracerebroventricularly with [myo-(3)H]inositol and treated with drugs 1 h after a pretreatment with lithium, which blocks the conversion of inositol monophosphate into free inositol. Systemic injection of the mGlu2/3 receptor agonist (-)-2-oxa-4-aminocyclo[3.1.0]hexane-4,6-dicarboxylic acid (LY379268) inhibited the stimulation of PI hydrolysis induced by the hallucinogenic 5-HT(2A) receptor agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) without affecting the stimulation by mGlu1/5 or muscarinic receptors. The action of LY379268 was prevented by the preferential mGlu2/3 receptor antagonist (2S,1'S,2'S)-2-(9-xanthylmethyl)-2-(2'-carboxycyclopropyl)glycine (LY341495). N-(4'-cyano-biphenyl-3-yl)-N-(3-pyridinylmethyl)-ethanesulfonamide hydrochloride (LY566332), a selective mGlu2 receptor enhancer, also reduced DOI-stimulated PI hydrolysis when combined with subthreshold doses of LY379268. Systemic LY379268 inhibited DOI-stimulated PI hydrolysis in mice lacking either mGlu2 or mGlu3 receptors but was inactive in double mGlu2/mGlu3 receptor knockout mice, suggesting that both mGlu2 and mGlu3 receptors interact with 5-HT(2A) receptors. Surprisingly, contrasting results were obtained in cortical slice preparations, where LY379268 amplified both DOI- and 3,5-dihydroxyphenylglycine-stimulated PI hydrolysis. Amplification was abrogated by the mGlu5 receptor antagonist 2-methyl-6-(phenylethynyl)pyridine, suggesting that experiments in brain slices are biased by an additional component of receptor-stimulated PI hydrolysis. This highlights the importance of in vivo models for the study of the interaction between 5-HT(2A) and mGlu2/3 receptors.


Assuntos
Lobo Frontal/efeitos dos fármacos , Fosfatidilinositóis/farmacologia , Receptor 5-HT2A de Serotonina/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Aminoácidos/farmacologia , Anfetaminas/farmacologia , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hidrólise , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Piridinas/farmacologia , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Receptores de Glutamato Metabotrópico/fisiologia , Sulfonamidas/farmacologia , Xantenos/farmacologia
16.
Neuroscience ; 158(4): 1599-607, 2009 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-19095043

RESUMO

Selective serotonin reuptake inhibitors (SSRIs), such as Prozac, are used to treat mood disorders. SSRIs attenuate (i.e. desensitize) serotonin 1A (5-HT(1A)) receptor signaling, as demonstrated in rats through decreased release of oxytocin and adrenocorticotropin hormone (ACTH) following 5-HT(1A) receptor stimulation. Maximal therapeutic effects of SSRIs for treatment of mood disorders, as well as effects on hypothalamic 5-HT(1A) receptor signaling in animals, take 1 to 2 weeks to develop. Estradiol also attenuates 5-HT(1A) receptor signaling, but, in rats, these effects occur within 2 days; thus, estrogens or selective estrogen receptor modulators may serve as useful short-term tools to accelerate desensitization of 5-HT(1A) receptors in response to SSRIs if candidate estrogen receptor targets in the hypothalamus are identified. We found high levels of GPR30, which has been identified recently as a pertussis-toxin (PTX) sensitive G-protein-coupled estrogen receptor, in the hypothalamic paraventricular nucleus (PVN) of rats. Double-label immunohistochemistry revealed that GPR30 co-localizes with 5-HT(1A) receptors, corticotrophin releasing factor (CRF) and oxytocin in neurons in the PVN. Pretreatment with PTX to the PVN before peripheral injections of 17-beta-estradiol 3-benzoate completely prevented the reduction of the oxytocin response to the 5-HT(1A) receptor agonist, (+)-8-hydroxy-2-dipropylaminotetralin (DPAT). Treatment with the selective GRP30 agonist, G-1, attenuated 5-HT(1A) receptor signaling in the PVN as measured by an attenuated oxytocin (by 29%) and ACTH (by 31%) response to DPAT. This study indicates that a putative extra-nuclear estrogen receptor, GPR30, may play a role in estradiol-mediated attenuation of 5-HT(1A) receptor signaling, and potentially in accelerating the effects of SSRIs in treatment of mood disorders.


Assuntos
Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Serotonina/metabolismo , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Hormônio Adrenocorticotrópico/sangue , Análise de Variância , Animais , Benzoatos/farmacologia , Hormônio Liberador da Corticotropina , Interações Medicamentosas , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Ovariectomia/métodos , Ocitocina/sangue , Toxina Pertussis/farmacologia , Radioimunoensaio/métodos , Ratos , Ratos Sprague-Dawley , Receptor 5-HT1A de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/farmacologia
17.
Neuropharmacology ; 55(4): 568-76, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18621067

RESUMO

Targeted-therapies enhancing differentiation of glioma-initiating cells (GICs) are potential innovative approaches to the treatment of malignant gliomas. These cells support tumour growth and recurrence and are resistant to radiotherapy and chemotherapy. We have found that GICs express mGlu3 metabotropic glutamate receptors. Activation of these receptors sustained the undifferentiated state of GICs in culture by negatively modulating the action of bone morphogenetic proteins, which physiologically signal through the phosphorylation of the transcription factors, Smads. The cross-talk between mGlu3 receptors and BMP receptors was mediated by the activation of the mitogen-activated protein kinase pathway. Remarkably, pharmacological blockade of mGlu3 receptors stimulated the differentiation of cultured GICs into astrocytes, an effect that appeared to be long lasting, independent of the growth conditions, and irreversible. In in vivo experiments, a 3-month treatment with the brain-permeant mGlu receptor antagonist, LY341495 limited the growth of infiltrating brain tumours originating from GICs implanted into the brain parenchyma of nude mice. While clusters of tumour cells were consistently found in the brain of control mice, they were virtually absent in a large proportion of mice treated with LY341495. These findings pave the way to a new non-cytotoxic treatment of malignant gliomas based on the use of mGlu3 receptor antagonists.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Receptores de Glutamato Metabotrópico/fisiologia , Transdução de Sinais/fisiologia , Aminoácidos/farmacologia , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Glioma/tratamento farmacológico , Glioma/patologia , Glioma/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosforilação/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Xantenos/farmacologia
18.
Neuropharmacology ; 55(4): 525-31, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18590921

RESUMO

Spontaneously depressed flinders sensitive line (FSL) rats showed a reduced expression of mGlu2/3 metabotropic glutamate receptors in the hippocampus, as compared to "non-depressed" flinders resistant line (FRL) rats. No changes in mGlu2/3 receptor protein levels were found in other brain regions, including the amygdala, hypothalamus, and cerebral cortex. Biochemical analysis of receptor signalling supported the reduction of mGlu2/3 receptors in the hippocampus of FSL rats. Accordingly, the selective mGlu2/3 receptor agonist, LY379268 (1microM) reduced forskolin-stimulated cAMP formation by 56% and 32% in hippocampal slices from FRL and FSL rats, respectively. In addition, LY379268 enhanced 3,5-dihydroxyphenylglycine-stimulated inositol phospholipid hydrolysis from 65% to 215% in hippocampal slices from FRL rats, whereas it was inactive in slices from FRL rats. We also examined the behavioural response of FSL rats to systemic injection of LY379268 (0.5mg/kg, i.p., once a day for 1-21 days) by measuring the immobility time in the forced swim test, which is known to be increased in these rats. LY379268 was administered alone or combined with the classical antidepressant, chlorimipramine (10mg/kg, i.p.). LY379268 alone had no effect at any of the selected time-points, whereas chlorimipramine alone reduced the immobility time only after 21 days of treatment. In contrast, when combined with LY379268, chlorimipramine reduced the immobility time during the first 14 days of treatment. These data support the view that mGlu2/3 receptors might be involved in the pathophysiology of depressive disorders, and that pharmacological activation of these receptors may shorten the latency of antidepressant medication.


Assuntos
Depressão/genética , Depressão/patologia , Hipocampo/metabolismo , Receptores de Glutamato Metabotrópico/deficiência , Aminoácidos/farmacologia , Animais , Antidepressivos Tricíclicos/farmacologia , Antidepressivos Tricíclicos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Clomipramina/farmacologia , Clomipramina/uso terapêutico , Colforsina/farmacologia , AMP Cíclico/metabolismo , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Interações Medicamentosas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Hipocampo/efeitos dos fármacos , Técnicas In Vitro , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , RNA Mensageiro/metabolismo , Ratos , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/metabolismo , Natação
19.
Radiol Med ; 113(4): 599-608, 2008 Jun.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-18536873

RESUMO

Evaluation of the legal implications of error in radiology and therefore the assessment of criminal and civil liability in the practice of the profession requires an analysis of how the public perception of the right to health has radically changed. This change has initiated a defensive approach to medicine and radiology that tends to be oriented towards precautionary measures, with a proliferation of often unnecessary imaging studies. In radiology, errors of omission or commission are frequent. A critical appraisal of the different types of error in radiology will help practitioners undertake the essential corrective measures. Through analysis of several cases derived from legal or insurance proceedings brought against radiologists, the most common forms of error are described, and their implications for criminal and civil liability are illustrated, although it is emphasised that the existence of an error does not always translate into the presence of malpractice.


Assuntos
Responsabilidade Legal , Imperícia/legislação & jurisprudência , Erros Médicos/legislação & jurisprudência , Radiologia/legislação & jurisprudência , Humanos , Itália , Doses de Radiação , Lesões por Radiação/prevenção & controle , Radioterapia
20.
Dis Esophagus ; 21(3): 262-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18430109

RESUMO

There is no clear consensus concerning the best endoscopic treatment of benign refractory esophageal strictures due to caustic ingestion. Different procedures are currently used: frequent multiple dilations, retrievable self-expanding stent, nasogastric intubation and surgery. We describe a new technique to fix a suspended esophageal silicone prosthesis to the neck in benign esophageal strictures; this permits us to avoid the frequent risk of migration of the expandable metallic or plastic stents. Under general anesthesia a rigid esophagoscope was placed in the patient's hypopharynx. Using transillumination from the optical device, the patient's neck was pierced with a needle. A n.0 monofilament surgical wire was pushed into the needle, grasped by a standard foreign body forceps through the esophagoscope and pulled out of the mouth (as in percutaneous endoscopic gastrostomy procedure). After tying the proximal end of the silicone prosthesis with the wire, it was placed through the strictures under endoscopic view. This procedure was successfully utilized in four patients suffering from benign refractory esophageal strictures due to caustic ingestion. The prosthesis and its suspension from the neck were well-tolerated until removal (mean duration 4 months). A postoperative transitory myositis was diagnosed in only one patient. One of the most frequent complications of esophageal prostheses in refractory esophageal strictures due to caustic ingestion is distal migration. Different solutions were proposed. For example the suspension of a wire coming from the nose and then fixed behind the ear. This solution is not considered optimal because of patient complaints and moreover the aesthetic aspect is compromised. The procedure we utilized in four patients utilized the setting of a silicone tube hanging from the neck in a way similar to that of endoscopic pharyngostomy. This solution is a valid alternative both for quality of life and for functional results.


Assuntos
Queimaduras Químicas/cirurgia , Estenose Esofágica/induzido quimicamente , Estenose Esofágica/cirurgia , Esofagoscopia , Próteses e Implantes , Adulto , Feminino , Humanos , Masculino
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