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1.
Phys Chem Chem Phys ; 18(5): 3910-20, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26765796

RESUMO

New insights into the reaction pathways of different potassium/magnesium amide-hydride based systems are discussed. In situ SR-PXD experiments were for the first time performed in order to reveal the evolution of the phases connected with the hydrogen releasing processes. Evidence of a new K-N-H intermediate is shown and discussed with particular focus on structural modification. Based on these results, a new reaction mechanism of amide-hydride anionic exchange is proposed.

2.
Scand J Med Sci Sports ; 24(5): e381-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25371933

RESUMO

The aim of the present study was to assess the validity of the classification system used in Open-class wheelchair tennis by investigating the relationship between post-impact ball velocity in the serve (measured using a sports radar gun) and the severity of impairment. Shoulder and wrist angles at the instant of ball impact were also estimated from 2D motion analysis. Forty-three nationally ranked Italian Open-class wheelchair tennis players were assigned to four groups (A­D) according to descending level of activity limitation. Ten successful flat serves (WFSs) and 10 successful kick serves (WKSs) for each player were recorded. One-way ANOVA showed that the severity of impairment significantly (P < 0.05) affected post-impact ball velocity and shoulder angle at the instant of ball impact. Furthermore, the mean value of post-impact ball velocity in WFS increased from group A to group D, i.e., with descending level of activity limitation. The results of this cross-sectional study indicate that the severity of impairment per se is associated with velocity of the wheelchair tennis serve, suggesting that the current classification is flawed in that it overlooks the impact of severity of impairment on players' performance.


Assuntos
Atletas/classificação , Desempenho Atlético/fisiologia , Esportes para Pessoas com Deficiência/fisiologia , Tênis/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Transversais , Avaliação da Deficiência , Humanos , Masculino , Cadeiras de Rodas
3.
Biol Sport ; 31(3): 209-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25177099

RESUMO

The purpose of this study was to investigate the rear knee angle range in the set position that allows sprinters to reach greater propulsion on the rear block during the sprint start. Eleven university-track team sprinters performed the sprint start using three rear knee angle conditions: 90°, 115° and 135°. A motion capture system consisting of 8 digital cameras (250 Hz) was used to record kinematic parameters at the starting block phase and the acceleration phase. The following variables were considered: horizontal velocity of the centre of mass (COM), COM height, block time, pushing time on the rear block, percentage of pushing time on the rear block, force impulse, push-off angle and length of the first two strides. The main results show that first, horizontal block velocity is significantly greater at 90° vs 115° and 135° rear knee angle (p<0.05 and p<0.001 respectively) at block clearance and the first two strides; second, during the pushing phase, the percentage of pushing time of the rear leg is significantly greater at 90° vs 135° rear knee angle (p<0.01). No significant difference was found for block time among the conditions. These results indicate that block velocity is the main kinematic parameter affected by rear knee angle during the starting block phase and acceleration phase. Furthermore, the 90° rear knee angle allows for a better push-off of the rear leg than larger angles at the set position. The findings of this study provide some direction and useful practical advice in defining an efficient rear leg biomechanical configuration at the set position.

4.
Neurol Sci ; 31 Suppl 3: 295-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20644975

RESUMO

At the end of 2006, a pharmacovigilance program on natalizumab was settled by the Italian Pharmaceutical Agency, and on January 2007, multiple sclerosis patients poorly responding to the immunomodulating therapies or with an aggressive clinical form of disease from onset initiated to be registered and to receive the medication. On February 2010, almost 3,000 cases have been treated with natalizumab. The drop-out rate is 10%. Almost 800 cases received cycles of natalizumab for more than 18 months. One case of PML was reported and other adverse events are similar to those described in phase III studies. The majority of cases remained stable, while in 25% of cases, an improvement of disability was documented.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Vigilância de Produtos Comercializados/tendências , Sistema de Registros , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Feminino , Humanos , Itália/epidemiologia , Masculino , Esclerose Múltipla/epidemiologia , Natalizumab , Sistema de Registros/estatística & dados numéricos
5.
Anal Chim Acta ; 1142: 201-210, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33280698

RESUMO

There is an increasing interest in determining the concentration of furanic compounds naturally formed in food aqueous matrices, by in situ, fast and low-cost methods. A sensor presenting such characteristics is here proposed, and characterized. It is based on a molecularly imprinted polymer (MIP) as a receptor with electrochemical transduction on a screen printed cell (SPC). The molecularly imprinted polymer has been developed for a particular furanic derivative, 2-furaldehyde (2-FAL). The detection bases on the reduction of 2-FAL selectively adsorbed on the polymer layer in contact with the working electrode. The polymer layer is simply formed by in situ polymerization, directly over the SPC and it was characterized by IR, SEM and electrochemical methods. Even if based on an easy and fast preparation procedure, the layer sufficiently adheres to the cell surface giving a reusable sensor. Square wave voltammetry (SWV) was applied as the signal acquisition method. The sensor performance in aqueous solution (NaCl 0.1 M) was tested, obtaining that the dose-response curve is fitted by the Langmuir adsorption isotherm. The sensitivity, and so the limit of detection, were noticeably improved by a chemometric approach based on the Design of experiment method. (optimized conditions: Estep = 0.03 V, Epulse = 0.066 V, f = 31 s-1). In water solution at pH around neutrality the dynamic range was from about 50 µM to 20 mM. Similar results were obtained for a white wine containing 12% ethanol, which has been considered as a typical example of beverage possibly containing furhaldehydes. The higher limit of quantification can be modulated by the amount of MIP deposited, while the lower detection limit by the conditions of the electrochemical measurement.


Assuntos
Impressão Molecular , Bebidas , Técnicas Eletroquímicas , Eletrodos , Furaldeído , Limite de Detecção , Polímeros Molecularmente Impressos
6.
Sci Rep ; 11(1): 10139, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980934

RESUMO

Post-operative cognitive dysfunction (POCD) is a debilitating clinical phenomenon in elderly patients. Management of pain in elderly is complicated because analgesic opiates elicit major side effects. In contrast, paracetamol (acetaminophen) has shown analgesic efficacy, no impact on cognition, and its side effects are well tolerated. We investigated the efficacy of paracetamol, compared to the opioid analgesic buprenorphine, in a model of POCD by investigating cognitive decline, allodynia, peripheral and hippocampal cytokines levels, and hippocampal microtubule dynamics as a key modulator of synaptic plasticity. A POCD model was developed in middle-aged (MA) rats by inducing a tibia fracture via orthopaedic surgery. Control MA rats did not undergo any surgery and only received isoflurane anaesthesia. We demonstrated that cognitive decline and increased allodynia following surgery was prevented in paracetamol-treated animals, but not in animals which were exposed to anesthesia alone or underwent the surgery and received buprenorphine. Behavioral alterations were associated with different peripheral cytokine changes between buprenorphine and paracetamol treated animals. Buprenorphine showed no central effects, while paracetamol showed modulatory effects on hippocampal cytokines and markers of microtubule dynamics which were suggestive of neuroprotection. Our data provide the first experimental evidence corroborating the use of paracetamol as first-choice analgesic in POCD.


Assuntos
Acetaminofen/farmacologia , Disfunção Cognitiva/tratamento farmacológico , Citoesqueleto/metabolismo , Complicações Cognitivas Pós-Operatórias/tratamento farmacológico , Complicações Cognitivas Pós-Operatórias/metabolismo , Fatores Etários , Analgésicos/farmacologia , Anestésicos , Animais , Cognição/efeitos dos fármacos , Citocinas/metabolismo , Gerenciamento Clínico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Projetos Piloto , Complicações Cognitivas Pós-Operatórias/etiologia , Ratos
7.
J Exp Med ; 163(6): 1583-8, 1986 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-3519831

RESUMO

A 10-12 kD lymphokine, herein termed TCAF, was recently shown to be secreted from Th after crosslinking of their antigen/MHC (T3-Ti) receptors. TCAF stimulates resting T lymphocyte proliferation via binding to surface components of the T11 pathway. To determine whether TCAF could induce antigen-independent activation of the lytic machinery of cytotoxic cells, the present studies were conducted. In the presence of TCAF, both T8+ class I MHC-specific and T4+ class II MHC-specific cytotoxic T cell clones were induced to kill targets, including those lacking the appropriate MHC molecules. This effect was unique to TCAF, since IL-1, IL-2, IFN-gamma could not stimulate lytic activity. Furthermore, both T3+T11+ and T3-T11+ NK clones were triggered to lyse NK-resistant target cells. These findings suggest that TCAF can function in an antigen-independent fashion to amplify cytotoxic effector responses.


Assuntos
Células Matadoras Naturais/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfocinas/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Anticorpos Monoclonais/imunologia , Células Clonais/efeitos dos fármacos , Testes Imunológicos de Citotoxicidade , Antígenos HLA/imunologia , Antígeno HLA-B7 , Interleucina-2/isolamento & purificação , Interleucina-2/farmacologia , Células Matadoras Naturais/imunologia , Linfócitos T Citotóxicos/classificação , Linfócitos T Citotóxicos/imunologia
8.
J Neurosci Res ; 87(2): 425-39, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18756517

RESUMO

We report on the structural and functional properties of the Helix contactin-related proteins (HCRPs), a family of closely related glycoproteins previously identified in the nervous system of the land snail Helix pomatia through antibodies against the mouse F3/contactin glycoprotein. We focus on HCRP1 and HCRP2, soluble FNIII domains-containing proteins of 90 and 45 kD bearing consensus motifs for both N- and O-glycosylation. Using the anti-HCRPs serum, we find secreted HCRPs in Helix nervous tissue isotonic extracts and in culture medium conditioned by Helix ganglia. In addition, we demonstrate expression of HCRPs on neuronal soma and on neurite extensions. Functionally, in Helix neurons, the antisense HCRP2 mRNA counteracts neurite elongation, and the recombinant HCRP2 protein exerts a strong positive effect on neurite growth when used as substrate. These data point to HCRPs as novel neurite growth-promoting molecules expressed in invertebrate nervous tissue.


Assuntos
Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Caracois Helix/fisiologia , Neurônios/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Células Cultivadas , Contactinas , Ensaio de Desvio de Mobilidade Eletroforética , Eletrofisiologia , Imuno-Histoquímica , Dados de Sequência Molecular , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Transfecção
9.
J Neurol Neurosurg Psychiatry ; 80(9): 1023-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19443471

RESUMO

OBJECTIVES: To assess the responsiveness of the three most used patient reported multiple sclerosis (MS) specific questionnaires: the Functional Assessment of MS (FAMS), the MS Impact Scale (MSIS-29) and the 54 item MS Quality of Life (MSQOL-54). DESIGN: Prospective multicentre longitudinal study on 104 MS patients treated with intravenous steroids for clinical exacerbation. METHODS: Patient reported data, Expanded Disability Status Scale (EDSS) score and clinical information were collected at admission and 8 weeks later. "Internal" (distribution based) responsiveness was assessed by standardised response means (SRM). "External" (anchor based) responsiveness was assessed by receiver operating characteristic (ROC) curves in relation to corresponding changes in a pre-specified reference measure (anchor). The pre-specified anchor was patients' self-reported recovery assessed on a 5 point Likert scale. RESULTS: SRM was 0.39 for FAMS, 0.58 for MSIS-29 physical scale, 0.45 for MSIS-29 psychological scale, 0.71 for MSQOL-54 physical health composite and 0.57 for MSQOL-54 mental health composite. Seventy-three patients (70%) reported they had improved; physicians agreed substantially with patient assessments (kappa statistic 0.70, 95% CI 0.54 to 0.85). Areas under ROC curves differed significantly from 0.50 only for the MSIS-29 and MSQOL-54 scales where areas ranged from 0.65 (95% CI 0.53 to 0.76) for the MSIS-29 psychological scale to 0.70 (95% CI 0.58 to 0.81) for the MSQOL-54 mental health composite. Areas under ROC curves assessed using a physician based anchor were similar to the patient based areas. CONCLUSIONS: The responsiveness of the MS specific instruments was less than ideal. The MSIS-29 and MSQOL-54 were significantly more responsive, using both distribution based and anchor based approaches, than FAMS, and should be preferred in longitudinal studies.


Assuntos
Esclerose Múltipla/terapia , Adolescente , Adulto , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Avaliação da Deficiência , Emoções/fisiologia , Feminino , Seguimentos , Nível de Saúde , Humanos , Injeções Intravenosas , Estudos Longitudinais , Masculino , Saúde Mental , Pessoa de Meia-Idade , Esclerose Múltipla/psicologia , Estudos Prospectivos , Qualidade de Vida , Curva ROC , Recidiva , Esteroides/administração & dosagem , Esteroides/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
Science ; 231(4742): 1118-22, 1986 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-2935936

RESUMO

A novel lymphokine with apparent molecular size of 10 to 12 kilodaltons is secreted from helper T cell clones within hours after cross-linking their T cell antigen-MHC (major histocompatibility complex) receptors (T3-Ti). This lymphokine, termed interleukin-4A (IL-4A), stimulates resting lymphocytes by binding to a surface component (or components) of the alternative T11 pathway and subsequently by inducing interleukin-2 (IL-2) receptors. The activation process is neither dependent on antigen specificities of the recruited population or the presence of macrophages. It appears, therefore, that IL-4A is a mediator involved in amplifying the T cell immune response.


Assuntos
Linfocinas/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T/imunologia , Anticorpos Monoclonais , Células Clonais , Humanos , Ativação Linfocitária , Peso Molecular , Receptores Imunológicos/análise , Receptores de Interleucina-2
11.
Neurol Sci ; 30 Suppl 2: S163-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19882367

RESUMO

At the end of 2006 a country-based surveillance program on natalizumab therapy in multiple sclerosis was settled in Italy by a collaborative effort of the Italian Drug Agency (AIFA) and a group of experts and neurologists appointed by the National Society of Neurology (SIN). After 2 years, 1,818 patients are registered in the database. The majority of cases (88.6%) failed the therapy with beta interferon or glatiramer acetate and had relapses or accumulated disability during immunomodulating treatment, while 11.4% of patients enrolled in the surveillance study were not previously treated with immunomodulating therapies and had a rapidly evolving clinical course. Almost 10% of the patients treated with natalizumab interrupted, for various different reasons, the therapy. Treatment was well tolerated and side effects were similar to those reported in the registrative studies. The majority of treated cases are stable or ameliorated.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Vigilância de Produtos Comercializados , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Itália , Imageamento por Ressonância Magnética , Masculino , Natalizumab , Pacientes Desistentes do Tratamento
12.
Cochrane Database Syst Rev ; (1): CD002819, 2007 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-17253481

RESUMO

BACKGROUND: Multiple sclerosis is a presumed cell-mediated autoimmune disease of the central nervous system. Cyclophosphamide (CFX) is a cytotoxic and immunosuppressive agent, used in systemic autoimmune diseases. Controversial results have been reported on its efficacy in MS. We conducted a systematic review of all relevant trials, evaluating the efficacy of CFX in patients with progressive MS. OBJECTIVES: The main objective was to determine whether CFX slows the progression of MS. SEARCH STRATEGY: We searched the Cochrane MS Group Trials Register (searched June 2006), Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3 2006), MEDLINE (January 1966 to June 2006), EMBASE (January 1988 to June 2006) and reference lists of articles. We also contacted researchers in the field. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating the clinical effect of CFX treatment in patients affected by clinically definite progressive MS.CFX had to be administered alone or in combination with adrenocorticotropic hormone (ACTH) or steroids. The comparison group had to be placebo or no treatment or the same co-intervention (ACTH or steroids) DATA COLLECTION AND ANALYSIS: Two reviewers independently decided the eligibility of the study, assessed the trial quality and extracted data. We also contacted study authors for original data. MAIN RESULTS: Of the 461 identified references, we initially selected 70: only four RCTs were included for the final analysis. Intensive immunosuppression with CFX (alone or associated with ACTH or prednisone) in patients with progressive MS compared to placebo or no treatment (152 participants) did not prevent the long-term (12, 18, 24 months) clinical disability progression as defined as evolution to a next step of Expanded Disability Status Scale (EDSS) score. However, the mean change in disability (final disability subtracted from the baseline) significantly favoured the treated group at 12 (effect size - 0.21, 95% confidence interval - 0.25 to -0.17) and 18 months (- 0.19, 95% confidence interval - 0.24 to - 0.14) but favoured the control group at 24 months (0.14, CI 0.07 to 0.21). We were unable to verify the efficacy of other schedules. Five patients died; sepsis and amenorrhea frequently occurred in treated patients (descriptive analysis). AUTHORS' CONCLUSIONS: We were unable to achieve all of the objectives specified for the review. This review shows that the overall effect of CFX (administered as intensive schedule) in the treatment of progressive MS does not support its use in clinical practice.


Assuntos
Ciclofosfamida/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
J Colloid Interface Sci ; 498: 271-281, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28342310

RESUMO

The synthesis of Ag nanoparticles from Ag+ has been investigated, with pectin acting both as reductant and coating.∼100% Ag+ to Ag(0) one-pot conversion was obtained, yielding p-AgNP, i.e. an aqueous solution of pectin-coated spherical Ag nanoparticles (d=8.0±2.6nm), with a<1ppm concentration of free Ag+ cation. Despite the low free Ag+ concentration and low Ag+ release with time, the nature of the coating allows p-AgNP to exert excellent antibacterial and antibiofilm actions, comparable to those of ionic silver, tested on E. coli (Gram-) and S. epidermidis (Gram+) both on planctonic cells and on pre- and post-biofilm formation conditions. Moreover, p-AgNP were tested on fibroblasts: not only p-AgNP were found to be cytocompatible but also revealed capable of promoting fibroblasts proliferation and to be effective for wound healing on model cultures. The antibacterial activity and the wound healing ability of silver nanoparticles are two apparently irreconcilable properties, as the former usually requires a high sustained Ag+ release while the latter requires low Ag+ concentration. p-AgNP represents an excellent compromise between opposite requirements, candidating as an efficient medication for repairing wounds and/or to treat vulnerable surgical site tissues, including the pre-treatment of implants as an effective prophylaxis in implant surgery.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Pectinas/química , Prata/química , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Tamanho da Partícula , Pectinas/farmacologia , Plâncton/citologia , Plâncton/efeitos dos fármacos , Prata/farmacologia , Nitrato de Prata/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Propriedades de Superfície
14.
J Physiol Pharmacol ; 67(6): 851-858, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28195065

RESUMO

Econazole is an anti-mycotic agent widely used for the treatment of cutaneous fungal infections, and for the therapy of vaginal candidiasis. Topical application of this azole is generally safe, although some patients have complained of mild burning sensation/cutaneous irritation and itching, especially when administered intravaginally. The underlying mechanisms responsible of these adverse effects are poorly understood, though they suggest excitation of cutaneous nociceptor terminals. We report that exposure of primary cultures of rat nociceptors to econazole augments neuronal excitability. This effect appears mediated by increments in the intracellular Ca2+ by stimulating Ca2+ entry and release from the endoplasmic reticulum. Ca2+ entry was not due to activation of thermo transient receptor potential (TRP) channels, suggesting a different ion channel targeted by the azole. Noteworthy, econazole-evoked responses were potentiated by a pro-inflammatory agent, which resulted in an increase in neuronal excitability. Econazole-elicited action potential firing was significantly abolished by the inflammatory cytokine inhibiting drug benzydamine via blockade of voltage-gated Na+ (Nav) channels. Collectively, our results indicate that the burning sensation of econazole is due at least in part to modulation of nociceptor excitability, and such sensation is increased in the presence of pro-inflammatory stimuli and blocked by benzydamine. These findings imply that a combination of the azole with benzydamine has the potential to reduce significantly the unpleasant symptoms related to infection and to the adverse effects of topical econazole formulations.


Assuntos
Benzidamina/farmacologia , Econazol/farmacologia , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Antifúngicos/farmacologia , Cálcio/metabolismo , Células Cultivadas , Citocinas/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Ratos , Ratos Wistar , Células Receptoras Sensoriais/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo
15.
Chem Commun (Camb) ; 52(26): 4836-9, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26971390

RESUMO

The Ca(BH4)2-Mg2NiH4 system presented here is, to the best of our knowledge, the first described Ca(BH4)2-based hydride composite that reversibly transfers boron from the Ca-based compound(s) to the reaction partner. The ternary boride MgNi2.5B2 is formed upon dehydrogenation and the formation of Ca(BH4)2 upon rehydrogenation is confirmed.

16.
Neuroscience ; 134(4): 1133-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16054762

RESUMO

Short-term activity-dependent synaptic plasticity has a fundamental role in short-term memory and information processing in the nervous system. Although the neuronal circuitry controlling different behaviors of land snails of the genus Helix has been characterized in some detail, little is known about the activity-dependent plasticity of synapses between identified neurons regulating specific behavioral acts. In order to study homosynaptic activity-dependent plasticity of behaviorally relevant Helix synapses independently of heterosynaptic influences, we sought to reconstruct them in cell culture. To this aim, we first investigated in culture the factors regulating synapse formation between Helix neurons, and then we studied the short-term plasticity of in vitro-reconstructed monosynaptic connections involved in the neural control of salivary secretion and whole-body withdrawal. We found that independently of extrinsic factors, cell-cell interactions are seemingly sufficient to trigger the formation of electrical and chemical synapses, although mostly inappropriate--in their type or association--with respect to the in vivo synaptic connectivity. The presence of ganglia-derived factors in the culture medium was required for the in vitro reestablishment of the appropriate in vivo-like connectivity, by reducing the occurrence of electrical connections and promoting the formation of chemical excitatory synapses, while apparently not influencing the formation of inhibitory connections. These heat-labile factors modulated electrical and chemical synaptogenesis through distinct protein tyrosine kinase signal transduction pathways. Taking advantage of in vitro-reconstructed synapses, we have found that feeding interneuron-efferent neuron synapses and mechanosensory neuron-withdrawal interneuron synapses display multiple forms of short-term enhancement-like facilitation, augmentation and posttetanic potentiation as well as homosynaptic depression. These forms of plasticity are thought to be relevant in the regulation of Helix feeding and withdrawal behaviors by inducing dramatic activity-dependent changes in the strength of input and output synapses of high-order interneurons with a crucial role in the control of Helix behavioral hierarchy.


Assuntos
Comportamento Alimentar/fisiologia , Caracois Helix/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Animais , Comunicação Celular/fisiologia , Células Cultivadas , Potenciais Pós-Sinápticos Excitadores/fisiologia , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Microscopia Eletrônica de Transmissão , Neurônios/ultraestrutura , Sinapses/ultraestrutura
17.
Eur J Hum Genet ; 3(5): 303-11, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8556305

RESUMO

To verify whether multiallelic polymorphisms belonging to HLA class II genes are linked to multiple sclerosis (MS) in the Italian population, we studied 28 multiplex MS families originating from different areas of Italy. Allelic characterization was carried out by analysis of RFLPs and oligonucleotide typing. Evidence supporting the existence of linkage between MS susceptibility and the HLA class II loci DRB1, DQA1 and DQB1 was provided using two non-parametric tests, affected sib-pair analysis, and affected-pedigree-member (APM) analysis. The APM analysis also suggested the existence of genetic heterogeneity for the HLA class II loci and MS susceptibility in our series. Linkage disequilibrium between MS susceptibility and the haplotype DRB1*1501,DQA1*0102,DQB1*0602 was demonstrated by applying the transmission linkage disequilibrium test to our families. Finally, lod score analysis suggests that in our Italian families, MS susceptibility is conferred by HLA class II alleles according to a low-penetrance autosomal recessive mode of inheritance.


Assuntos
Genes MHC da Classe II , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Alelos , Distribuição de Qui-Quadrado , Feminino , Genes Recessivos , Ligação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Itália/epidemiologia , Escore Lod , Masculino , Epidemiologia Molecular , Esclerose Múltipla/etnologia , Linhagem , Estatísticas não Paramétricas
18.
J Immunol Methods ; 174(1-2): 249-57, 1994 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-8083529

RESUMO

Chemokines are a superfamily of structurally related cytokines involved in leukocyte recruitment in normal and neoplastic tissues. The availability of non-cross-reacting reagents specific for each member of the C-C and C-X-C family is important for careful characterization of their in vitro and in vivo production and relevance. Here we describe a novel, highly specific, mAb against monocyte chemotactic protein-1 (MCP-1). The 5D3-F7 mAb (IgG1,kappa) recognizes human recombinant and natural MCP-1 in ELISA, immunoprecipitation and immunoblot analysis. As a source of natural MCP-1 we used the 8387 human sarcoma line which produces spontaneously MCP-1 and responds to TNF with increased expression and release. The 5D3-F7 mAb inhibited the chemotactic activity of MCP-1 for monocytes. Using the 5D3-F7 mAb and a polyclonal rabbit anti-MCP-1 serum, a sandwich ELISA was developed. In both the direct and the sandwich ELISA, the 5D3-F7 mAb recognized human MCP-1, but not the closely related C-C chemokines MCP-1, MCP-2, MCP-3, MIP-1 alpha, and RANTES and the C-X-C chemokines IL-8, gro alpha and NAP-2. In culture supernatants the sensitivity of the sandwich ELISA was approximately equal to 30 pg/ml. The sandwich ELISA permitted detection of MCP-1 in resting or cytokine-stimulated endothelial, mesothelial and Kaposi's sarcoma cells. Preliminary immunohistochemical analysis revealed production of MCP-1 by macrophage-like cells at sites of inflammation. The 5D3-F7 mAb provides a novel, highly specific reagent with which to investigate the in vitro and in vivo production and role of MCP-1.


Assuntos
Anticorpos Monoclonais/imunologia , Fatores Quimiotáticos/imunologia , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Quimiocina CCL2 , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Técnicas Imunoenzimáticas , Proteínas Recombinantes/imunologia
19.
J Neuroimmunol ; 79(1): 76-83, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9357450

RESUMO

The in vivo effects on the expression of adhesion molecules and on the adhesion between mononuclear cells and multiple sclerosis human brain endothelial cells (MS-HBECs) were investigated at the beginning of beta-IFN-1b treatment of MS patients. MS-HBECs were isolated from a surgical specimen obtained from an MS patient undergoing brain surgery for vascular aneurysm. 48 h after the first single administration of beta-IFN-1b, PBMNCs of 10 MS patients were analyzed for HLA-DR, CD11a, CD18 and VLA-4 expression and the adhesion between PBMNCs and both stimulated and unstimulated MS-HBECs evaluated. sICAM-1 and sVCAM-1 dosage in the serum of the patients was checked as well. The experiments were repeated using HUVECs in order to detect possible endothelial organ-specific differences. The experiments were also performed after six months of beta-INF-1b treatment on HUVECs. No significant effects on mononuclear cells/endothelium adhesion were detected at 48 h, but adhesion of PBMNCs to HUVECs decreased at six months. An increase in HLA-DR and VLA-4 and a decrease of CD18 was detected in monocytes. The serum level of sVCAM-1 increased at T2 and was still higher than at T0 at six months. The effect of the beta-IFN-1b treatment on both MS-HBECs and HUVECs, was selectively studied in vitro by testing the expression of cytokine-induced adhesion molecules HLA-DR, ICAM-1 and VCAM-1. The in vitro experiments confirmed that beta-IFN-1b is able to antagonize gamma-IFN-induced HLA-DR expression on MS human brain endothelial cells without relevant effects on VCAM-1 and ICAM-1.


Assuntos
Circulação Cerebrovascular/fisiologia , Endotélio Vascular/fisiopatologia , Interferon beta/uso terapêutico , Monócitos/fisiologia , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/fisiopatologia , Veias Umbilicais/fisiopatologia , Adulto , Antígenos/análise , Adesão Celular/efeitos dos fármacos , Endotélio Vascular/citologia , Feminino , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interferon beta-1a , Interferon beta-1b , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Esclerose Múltipla/patologia , Veias Umbilicais/patologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
20.
Biotechniques ; 13(6): 876-9, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1282346

RESUMO

The nucleotide analogue digoxigenin-11-dUTP is widely used as a nonradioactive marker in a broad range of techniques including dot blots, Southern and Northern blots, colony and plaque screenings and in situ hybridizations. In this report, we describe the incorporation of this molecule into a cDNA synthesized by reverse transcriptase as a novel application for digoxigenin. This reaction can be performed as a useful control to check the integrity of a bulk mRNA preparation in the construction of a cDNA library, since the ability of mRNA to direct the synthesis of long molecules of first-strand cDNA is a sign of its integrity.


Assuntos
DNA/biossíntese , Nucleotídeos de Desoxiuracil , Digoxigenina/análogos & derivados , RNA Mensageiro/genética , DNA/genética , Sondas de DNA , Estudos de Avaliação como Assunto , Técnicas Genéticas , Técnicas de Sonda Molecular , DNA Polimerase Dirigida por RNA/metabolismo
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