Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
BMC Pulm Med ; 19(1): 111, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221137

RESUMO

BACKGROUND: Interstitial lung disease (ILD) is a severe systemic manifestation of rheumatoid arthritis (RA). High-resolution computed tomography (HRCT) represents the gold standard for the diagnosis of ILD, but its routine use for screening programs is not advisable because of both high cost and X-ray exposure. Velcro crackles at lung auscultation occur very early in the course of interstitial pneumonia, and their detection is an indication for HRCT. Recently, we developed an algorithm (VECTOR) to detect the presence of Velcro crackles in pulmonary sounds and showed good results in a small sample of RA patients. The aim of the present investigation was to validate the diagnostic accuracy of VECTOR in a larger population of RA patients, compared with that of the reference standard of HRCT, from a multicentre study. METHODS: To avoid X-ray exposure, we enrolled 137 consecutive RA patients who had recently undergone HRCT. Lung sounds of all patients were recorded in 4 pulmonary fields bilaterally with a commercial electronic stethoscope (ES); subsequently, all HRCT images were blindly evaluated by a radiologist, and audio data were analysed by means of VECTOR. RESULTS: Fifty-nine of 137 patients showed ILD (43.1%). VECTOR correctly classified 115/137 patients, showing a diagnostic accuracy of 83.9% and a sensitivity and specificity of 93.2 and 76.9%, respectively. CONCLUSIONS: VECTOR may represent the first validated tool for the screening of RA patients who are suspected for ILD and who should be directed to HRCT for the diagnosis. Moreover, early identification of RA-ILD could contribute to the design of prospective studies aimed at elucidating unclear aspects of the disease.


Assuntos
Artrite Reumatoide/complicações , Auscultação/instrumentação , Doenças Pulmonares Intersticiais/diagnóstico , Sons Respiratórios/diagnóstico , Idoso , Algoritmos , Feminino , Humanos , Pulmão/fisiopatologia , Doenças Pulmonares Intersticiais/etiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
2.
J Dairy Sci ; 97(2): 642-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24342684

RESUMO

The use of raw milk in the processing of buffalo Mozzarella cheese is permitted, but the heat treatment used for stretching the curd must ensure that the final product does not contain pathogens such as Shiga toxin-producing Escherichia coli (STEC) that may be present on buffalo dairy farms. This study carried out challenge tests at temperatures between 68 °C and 80 °C for 2 to 10 min to simulate curd temperatures during the stretching phase. Curd samples were inoculated with 2 STEC strains (serotypes O157 and O26), and their inactivation rates were assessed in the different challenge tests. The curd samples were digested with papain to ensure a homogeneous dispersion of bacteria. The STEC cells were counted after inoculation (range 7.1-8.7 log cfu/g) and after heat treatments using the most probable number (MPN) technique. A plot of log MPN/g versus time was created for each separate experiment. The log linear model with tail was used to provide a reasonable fit to observed data. Maximum inactivation rate (k(max), min(-1)), residual population (log MPN/g), decimal reduction time (min), and time for a 4D (4-log10) reduction (min) were estimated at each temperature tested. A 4D reduction of the O26 STEC strain was achieved when curd was heated at 68 °C for 2.6 to 6.3 min or at 80 °C for 2.1 to 2.3 min. Greater resistance was observed for the O157 strain at 68 °C because k(max) was 1.48 min(-1). The model estimates can support cheesemakers in defining appropriate process criteria needed to control possible STEC contamination in raw milk intended for the production of Mozzarella.


Assuntos
Queijo/microbiologia , Microbiologia de Alimentos , Escherichia coli Shiga Toxigênica/fisiologia , Animais , Búfalos , Contagem de Colônia Microbiana , Escherichia coli O157/fisiologia , Temperatura Alta , Cinética
3.
Front Pharmacol ; 14: 1267414, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035009

RESUMO

Lysophosphatidic acid (LPA) is a bioactive phospholipid that acts as an agonist of six G protein-coupled receptors named LPA receptors (LPA1-6). LPA elicits diverse intracellular events and modulates several biological functions, including cell proliferation, migration, and invasion. Overactivation of the LPA-LPA receptor system is reported to be involved in several pathologies, including cancer, neuropathic pain, fibrotic diseases, atherosclerosis, and type 2 diabetes. Thus, LPA receptor modulators may be clinically relevant in numerous diseases, making the identification and pharmacodynamic characterization of new LPA receptor ligands of strong interest. In the present work, label-free dynamic mass redistribution (DMR) assay has been used to evaluate the pharmacological activity of some LPA1 and LPA2 standard antagonists at the recombinant human LPA1 and LPA2 receptors. These results are compared to those obtained in parallel experiments with the calcium mobilization assay. Additionally, the same experimental protocol has been used for the pharmacological characterization of the new compound CHI. KI 16425, RO 6842262, and BMS-986020 behaved as LPA1 inverse agonists in DMR experiments and as LPA1 antagonists in calcium mobilization assays. Amgen compound 35 behaved as an LPA2 antagonist, while Merck compound 20 from WO2012028243 was detected as an LPA2 inverse agonist using the DMR test. Of note, for all the compounds, similar potency values were estimated by DMR and calcium assay. The new compound CHI was found to be an LPA1 inverse agonist, but with potency lower than that of the standard compounds. In conclusion, we have demonstrated that DMR assay can be successfully used to characterize LPA1 and LPA2 ligands. Compared to the classical calcium mobilization assay, DMR offers some advantages, in particular allowing the identification of inverse agonists. Finally, in the frame of this study, a new LPA1 inverse agonist has been identified.

4.
Nat Med ; 6(2): 151-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10655102

RESUMO

Trypsin and mast cell tryptase cleave proteinase-activated receptor 2 and, by unknown mechanisms, induce widespread inflammation. We found that a large proportion of primary spinal afferent neurons, which express proteinase-activated receptor 2, also contain the proinflammatory neuropeptides calcitonin gene-related peptide and substance P. Trypsin and tryptase directly signal to neurons to stimulate release of these neuropeptides, which mediate inflammatory edema induced by agonists of proteinase-activated receptor 2. This new mechanism of protease-induced neurogenic inflammation may contribute to the proinflammatory effects of mast cells in human disease. Thus, tryptase inhibitors and antagonists of proteinase-activated receptor 2 may be useful anti-inflammatory agents.


Assuntos
Inflamação/etiologia , Receptores de Trombina/agonistas , Animais , Sequência de Bases , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Quimases , Sondas de DNA , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Humanos , Hibridização In Situ , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Receptor PAR-2 , Receptores de Trombina/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais , Substância P/metabolismo , Tripsina/metabolismo , Triptases
5.
Handb Exp Pharmacol ; (187): 49-61, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18825335

RESUMO

The transient receptor potential (TRP) family of channels is represented by at least six members in primary sensory neurons. These include the TRP vanilloid subtypes 1 (TRPV1), 2, 3, and 4, the cold and menthol receptor TRPM8, and TRPA1. Much interest has been directed to the study of the TRPV1, because capsaicin has been instrumental in discovering the unique role of a subset of primary sensory neurons in causing nociceptive responses, in activating reflex pathways including cough, and in producing neurogenic inflammation. TRPV1 is now regarded as an integrator of diverse sensory modalities because it undergoes marked plasticity and sensitization through a variety of mechanisms, including activation of G-protein-coupled or tyrosine kinase receptors. Evidence in experimental animals and in patients with airway diseases indicates a marked hypersensitivity to cough induced by TRPV1 agonists. Recent studies with newly developed high-affinity and selective TRPV1 antagonists have revealed that TRPV1 inhibition reduces cough induced by citric acid or antigen challenge.


Assuntos
Tosse/fisiopatologia , Canais de Potencial de Receptor Transitório/fisiologia , Animais , Tosse/patologia , Humanos , Neurite (Inflamação)/patologia , Neurite (Inflamação)/fisiopatologia , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/fisiologia
6.
Gut ; 57(5): 628-33, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18182589

RESUMO

BACKGROUND AND AIMS: It has recently been described that bradykinin B(2) receptors are expressed in the human gallbladder and that their activation induces a powerful contraction, especially in acute cholecystitis tissues. Here the role of the B(1) receptor in the contractility of control and inflamed human gallbladder was investigated. METHODS: Strips of human gallbladder from either acute gallstone cholecystitis or elective gastro-entero-pancreatic surgery (control) were assessed in vitro and processed for reverse transcription-PCR analysis. Cumulative concentration-response curves with the selective B(1) receptor agonist, Lys-Des-Arg(9)-bradykinin, cholecystokinin and carbachol were performed in control and cholecystitis specimens. RESULTS: Lys-Des-Arg(9)-bradykinin concentration-dependently contracted strips of control gallbladders and its motor effect was higher in inflamed gallbladders. Lys-Des-Arg(9)-bradykinin-induced contraction was not altered by pretreatment with the selective bradykinin B(2) receptor antagonist, HOE140 (1 microM), the NK(1) (SR140333), NK(2) (SR48968) and NK(3) (SR142801) tachykinin receptor antagonists (all 1 microM), the muscarinic acetylcholine receptor antagonist, atropine (1 microM), and the cyclo-oxygenase inhibitor, indomethacin (5 microM). In contrast, the Lys-Des-Arg(9)-bradykinin-induced motor response was significantly reduced by the selective B(1) receptor antagonist, R-715. Finally, quantitative real-time PCR analysis indicated that B(1) receptor mRNA levels were significantly higher in cholecystitis smooth muscle specimens, when compared with that observed in control tissues. CONCLUSIONS: Bradykinin B(1) receptor has an important role as a spasmogen of human gallbladder, and selective antagonists of the B(1) receptor may represent a valid therapeutic option to control pain in patients with acute cholecystitis.


Assuntos
Antagonistas de Receptor B1 da Bradicinina , Antagonistas de Receptor B2 da Bradicinina , Colecistite/tratamento farmacológico , Vesícula Biliar/efeitos dos fármacos , Adulto , Idoso , Atropina/farmacologia , Colecistite/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Feminino , Vesícula Biliar/fisiologia , Humanos , Indometacina/farmacologia , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/farmacologia , Receptor B1 da Bradicinina/metabolismo , Receptor B2 da Bradicinina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Cephalalgia ; 28(1): 9-17, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17888011

RESUMO

Ethanol stimulating transient receptor potential vanilloid 1 (TRPV1) on primary sensory neurons promotes neurogenic inflammation, including calcitonin gene-related peptide (CGRP)-mediated coronary dilation. Alcoholic beverages trigger migraine attacks and activation of trigeminal neurons plays a role in migraine. We have investigated in guinea pigs whether ethanol by TRPV1 stimulation causes neurogenic inflammation in the trigeminovascular system. Ethanol-evoked release of neuropeptides from slices of dura mater was abolished by Ca(2+) removal, capsaicin pretreatment and the TRPV1 antagonist, capsazepine. Intragastric ethanol increased plasma extravasation in dura mater, an effect abolished by capsazepine and the NK1 receptor antagonist, SR140333, and caused vasodilation around the middle meningeal artery, an effect abolished by capsazepine and the CGRP receptor antagonist, BIBN4096BS. Vasodilation of meningeal vessels by TRPV1 activation and CGRP release may be relevant to the mechanism by which alcohol ingestion triggers migraine attacks.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Etanol/farmacologia , Canais de Cátion TRPV/metabolismo , Gânglio Trigeminal/irrigação sanguínea , Gânglio Trigeminal/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Animais , Dura-Máter/irrigação sanguínea , Dura-Máter/efeitos dos fármacos , Dura-Máter/metabolismo , Cobaias , Masculino , Canais de Cátion TRPV/fisiologia , Gânglio Trigeminal/metabolismo , Vasodilatação/fisiologia , Vasodilatadores/farmacologia
8.
Nat Neurosci ; 5(6): 546-51, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11992116

RESUMO

The vanilloid receptor-1 (VR1) is a heat-gated ion channel that is responsible for the burning sensation elicited by capsaicin. A similar sensation is reported by patients with esophagitis when they consume alcoholic beverages or are administered alcohol by injection as a medical treatment. We report here that ethanol activates primary sensory neurons, resulting in neuropeptide release or plasma extravasation in the esophagus, spinal cord or skin. Sensory neurons from trigeminal or dorsal root ganglia as well as VR1-expressing HEK293 cells responded to ethanol in a concentration-dependent and capsazepine-sensitive fashion. Ethanol potentiated the response of VR1 to capsaicin, protons and heat and lowered the threshold for heat activation of VR1 from approximately 42 degrees C to approximately 34 degrees C. This provides a likely mechanistic explanation for the ethanol-induced sensory responses that occur at body temperature and for the sensitivity of inflamed tissues to ethanol, such as might be found in esophagitis, neuralgia or wounds.


Assuntos
Capsaicina/análogos & derivados , Etanol/farmacologia , Nociceptores/efeitos dos fármacos , Nociceptores/fisiologia , Receptores de Droga/fisiologia , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Etanol/administração & dosagem , Gânglios Espinais/citologia , Gânglios Espinais/efeitos dos fármacos , Temperatura Alta , Humanos , Masculino , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Concentração Osmolar , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Limiar Sensorial/efeitos dos fármacos , Substância P/metabolismo , Canais de Cátion TRPV , Termorreceptores/efeitos dos fármacos , Termorreceptores/fisiologia , Gânglio Trigeminal/citologia , Gânglio Trigeminal/efeitos dos fármacos
9.
Biomed Res Int ; 2017: 1609836, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28904945

RESUMO

The kneading treatment of the fresh curd in hot water is a critical control point in the manufacturing of mozzarella. Factors such as the ratio between hot water and curd mass, the rheological properties, and the mixing and kneading activity affect the processing time and the internal temperature of the curd. The aim of this study was to investigate the effect of thermal treatments on the fate of Shiga toxin-producing Escherichia coli (STEC). Nine curd samples (weight 160-270 g) were artificially contaminated with O157 or O26 STEC and stretched in hot water (90-95°C) for 5-10 min. Depending on the heating process and spinning, different nonisothermal profiles were recorded. Observed reductions of O157 and O26 STEC varied between 1.01 and more than 5.38 log⁡MPN (Most Probable Number)/g at the end of the temperature treatments. Further, nonisothermal log-linear tail models were developed to compare observed reductions for O157 and O26 VTEC under variable temperature conditions. Results obtained showed that the comparison of predictions provided by the dynamic model with observations described well the linear inactivation pattern since nonsignificant differences were denoted at all profiles tested. The dynamic model developed can be useful to evaluate the effectiveness of the thermal treatments used in the manufacturing of mozzarella in the inactivation of STEC.


Assuntos
Infecções por Escherichia coli/prevenção & controle , Escherichia coli O157/patogenicidade , Temperatura Alta , Escherichia coli Shiga Toxigênica/patogenicidade , Infecções por Escherichia coli/microbiologia , Manipulação de Alimentos , Microbiologia de Alimentos , Humanos , Carne/microbiologia , Toxina Shiga/química , Água
10.
J Health Popul Nutr ; 24(3): 282-97, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17366770

RESUMO

The Bangladesh Arsenic Mitigation and Water Supply Program (BAMWSP) has compiled field-kit measurements of the arsenic content of groundwater for nearly five million wells. By comparing the spatial distribution of arsenic inferred from these field-kit measurements with geo-referenced laboratory data in a portion of Araihazar upazila, it is shown here that the BAMWSP data could be used for targeting safe aquifers for the installation of community wells in many villages of Bangladesh. Recent experiences with mobile-phone technology to access and update the BAMWSP data in the field are also described. It is shown that the technology, without guaranteeing success, could optimize interventions by guiding the choice of the drilling method that is likely to reach a safe aquifer and identifying those villages where exploratory drilling is needed.


Assuntos
Arsênio/análise , Água Doce/análise , Sistemas de Informação Geográfica , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Bangladesh , Monitoramento Ambiental , Humanos
11.
J Neurosci ; 21(4): 1104-9, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11160380

RESUMO

Recently, the cannabinoid (CB) receptor agonist anandamide (AEA) has been shown to excite perivascular terminals of primary sensory neurons via activation of the vanilloid receptor-1 (VR-1). To determine whether AEA stimulates central terminals of these neurons, via VR-1 activation, we studied the release of calcitonin gene-related peptide (CGRP)- and substance P (SP)-like immunoreactivities (LI) from slices of rat dorsal spinal cord. Mobilization of Ca(2+) in rat dorsal root ganglion (DRG) neurons in culture was also studied. AEA (0.1-10 micrometer) increased the outflow of CGRP-LI and SP-LI from slices of the rat dorsal spinal cord in a Ca(2+)-dependent manner and increased [Ca(2+)](i) in capsaicin-sensitive cultured DRG neurons. Both effects of AEA were abolished by capsaicin pretreatment and by the VR-1 antagonist capsazepine but not affected by the CB receptor antagonists AM281 or AM630. Both neuropeptide release and Ca(2+) mobilization induced by electrical field stimulation (EFS) were inhibited by a low concentration of AEA (10 nm). Inhibition by AEA of EFS-induced responses was reversed by AM281 and AM630, but was not affected by capsazepine. Results indicate that stimulation of VR-1 with high concentrations of AEA excites central terminals of capsaicin-sensitive DRG neurons, thus causing neuropeptide release in the dorsal spinal cord. This novel activity opposes the CB receptor-mediated inhibitory action of low concentrations AEA. However, only if large amounts of endogenous AEA could be produced at the level of the dorsal spinal cord, they may not inhibit, but rather activate, nociceptive sensory neurons.


Assuntos
Ácidos Araquidônicos/farmacologia , Capsaicina/análogos & derivados , Gânglios Espinais/metabolismo , Neurônios Aferentes/metabolismo , Terminações Pré-Sinápticas/efeitos dos fármacos , Receptores de Droga/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Cálcio/metabolismo , Capsaicina/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Endocanabinoides , Gânglios Espinais/citologia , Gânglios Espinais/efeitos dos fármacos , Técnicas In Vitro , Masculino , Neurônios Aferentes/citologia , Neurônios Aferentes/efeitos dos fármacos , Alcamidas Poli-Insaturadas , Ratos , Receptores de Canabinoides , Receptores de Droga/agonistas , Receptores de Droga/antagonistas & inibidores , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Substância P/metabolismo , Canais de Cátion TRPV
12.
Vet Res Commun ; 29 Suppl 2: 107-12, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16244934

RESUMO

Risk assessment is a tool used by manufacturers, governmental, or regulatory bodies to evaluate the safety of food production systems and decide on strategies to protect consumers. This article presents a general approach to the use of probabilistic models to assess the risk related to specific hazards in some categories of food. It discusses their value in organising and analysing the scientific knowledge about the factors that most affect risk along the food production chain, but also highlights the data gaps that currently hamper accurate risk assessment.


Assuntos
Indústria de Processamento de Alimentos/normas , Doenças Transmitidas por Alimentos/etiologia , Modelos Estatísticos , Medição de Risco/métodos , Animais , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/prevenção & controle , Humanos , Organização Mundial da Saúde
13.
Br J Pharmacol ; 129(5): 915-20, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10696090

RESUMO

The tachykinin, neurokinin A (NKA), contracts guinea-pig airways both in vitro and in vivo, preferentially activating smooth muscle NK(2) receptors, although smooth muscle NK(1) receptors may also contribute. In vitro evidence suggests that NKA activates epithelial NK(1) receptors, inducing the release of nitric oxide (NO) and subsequent smooth muscle relaxation. A number of selective NK(1) receptor agonists have been reported to activate both smooth muscle and epithelial NK(1) receptors, however septide appears only to activate smooth muscle NK(1) receptors. The aim of the present study was to investigate whether NKA-induced bronchoconstriction in guinea-pigs in vivo may be limited by NO release via NK(1) receptor activation, and whether selective NK(1) receptor agonists may activate this mechanism differently. Aerosolized NKA caused an increase in total pulmonary resistance (RL) that was markedly reduced by the NK(2) receptor antagonist, SR 48968, and abolished by the combination of SR 48968 and the NK(1) receptor antagonist, CP-99, 994. The increase in RL evoked by NKA was potentiated by pretreatment with the NO synthase (NOs) inhibitor, L-NAME, but not by the inactive enantiomer D-NAME. Potentiation by L-NAME of NKA-induced increase in RL was reversed by L-Arginine, but not by D-Arginine. Pretreatment with L-NAME did not affect the increase in RL induced by the selective NK(2) receptor agonist, [beta-Ala(8)]NKA(4-10), and by the selective NK(1) receptor agonist, septide, whereas it markedly potentiated the increase in RL caused by a different NK(1) selective agonist, [Sar(9),Met(O(2))(11)]SP. Dose-response curves showed that septide was a more potent bronchoconstrictor than [Sar(9),Met(O(2))(11)]SP to cause bronchoconstriction. Pretreatment with the NK(1) receptor antagonist, CP-96,994, abolished the ability of L-NAME to increase bronchoconstriction to aerosolized NKA. Bronchoconstriction to aerosolized NKA was increased by L-NAME, after pretreatment with the NK(3) receptor antagonist, SR 142801. The present study shows that in vivo bronchoconstriction in response to the aerosolized naturally occurring tachykinin, NKA, is limited by its own ability to release relaxant NO via NK(1) receptor activation. This receptor is apparently insensitive to septide, thus justifying, at least in part, the high potency of septide to cause bronchoconstriction in guinea-pigs.


Assuntos
Broncoconstrição/efeitos dos fármacos , Neurocinina A/antagonistas & inibidores , Óxido Nítrico/fisiologia , Fragmentos de Peptídeos/farmacologia , Receptores da Neurocinina-1/efeitos dos fármacos , Substância P/análogos & derivados , Aerossóis , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Cobaias , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Neurocinina A/administração & dosagem , Neurocinina A/farmacologia , Antagonistas dos Receptores de Neurocinina-1 , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III , Ácido Pirrolidonocarboxílico/análogos & derivados , Receptores da Neurocinina-1/agonistas , Receptores da Neurocinina-2/agonistas , Receptores da Neurocinina-2/antagonistas & inibidores , Receptores da Neurocinina-2/efeitos dos fármacos , Receptores de Taquicininas/agonistas , Receptores de Taquicininas/antagonistas & inibidores , Substância P/farmacologia
14.
Br J Pharmacol ; 131(4): 689-94, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11030717

RESUMO

We have investigated the ability of protease-activated receptor-1 (PAR-1), PAR-2, PAR-3 and PAR-4 agonists to induce contractile responses in isolated guinea-pig gallbladder. Thrombin, trypsin, mouse PAR-1 activating (SFLLRN-NH(2)) peptide, and mouse PAR-2 activating (SLIGRL-NH(2)) and human PAR-2 activating (SLIGKV-NH(2)) peptides produced a concentration-dependent contractile response. Mouse PAR-4 activating (GYPGKF-NH(2)) peptide, the mouse PAR-1 reverse (NRLLFS-NH(2)) peptide, the mouse PAR-2 reverse (LRGILS-NH(2)) and human PAR-2 reverse (VKGILS-NH(2)) peptides caused negligible contractile responses at the highest concentrations tested. An additive effect was observed following the contractile response induced by either trypsin or thrombin, with the addition of a different PAR agonist (SFLLRN-NH(2) and SLIGRL-NH(2), respectively). Desensitization to PAR-2 activating peptide attenuated the response to trypsin but failed to attenuate the response to PAR-1 agonists, and conversely desensitization to PAR-1 attenuated the response to thrombin but failed to alter contractile responses to PAR-2 agonists. The contractile responses produced by thrombin, trypsin, SFLLRN-NH(2) and SLIGRL-NH(2) were markedly reduced in the presence of the cyclo-oxygenase inhibitor, indomethacin, whilst the small contractile response produced by NRLLFS-NH(2) and LRGILS-NH(2) were insensitive to indomethacin. The contractile responses to thrombin, trypsin, SFLLRN-NH(2) and SLIGRL-NH(2) were unaffected by the presence of: the non-selective muscarinic antagonist, atropine; the nitric oxide synthase inhibitor, L-NAME; the sodium channel blocker, tetrodotoxin; the combination of selective tachykinin NK(1) and NK(2) receptor antagonists, (S)-1-[2-[3-(3,4-dichlorphenyl)-1 (3-isopropoxyphenylacetyl) piperidin-3-yl] ethyl]-4-phenyl-1 azaniabicyclo [2.2.2] octane chloride (SR140333) and (S)-N-methyl-N-[4-acetylamino-4-phenylpiperidino-2-(3, 4-dichlorophenyl)-butyl] benzamide (SR48968), respectively. The results indicate that PAR-1 and PAR-2 activation causes contractile responses in the guinea-pig gallbladder, an effect that is mediated principally by prostanoid release, and is independent of neural mechanisms.


Assuntos
Proteínas de Caenorhabditis elegans , Vesícula Biliar/fisiologia , Proteínas de Helminto/fisiologia , Contração Muscular , Prostaglandinas/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Relação Dose-Resposta a Droga , Vesícula Biliar/efeitos dos fármacos , Cobaias , Humanos , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Substância P/farmacologia , Trombina/farmacologia
15.
Br J Pharmacol ; 126(6): 1293-300, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10217521

RESUMO

1. Motor responses to des-Arg9-bradykinin and bradykinin were studied in the isolated mouse trachea (precontracted with carbachol, 10 microM) and the urinary bladder of either Swiss, C57B1/6J or bradykinin B2 receptor knockout (Bk2r(-/-)) mice after 1-6 h in vitro. The expression of mRNA for the mouse B1 receptor in tracheal and urinary bladder tissues was also studied by using Northern blot analysis. 2. In isolated tracheae, des-Arg9-bradykinin produced a relaxant response that increased over time: no response was observed after 1 h of incubation, whereas after 6 h the maximum response (1 microM) was 68-84% of the relaxation produced by isoproterenol (1 microM) in the three mouse strains. The relaxant response to bradykinin (1 microM) observed at 1 h (38-51% of isoproterenol) was increased (62-65% of isoproterenol) after 6 h in Swiss and C57B1/6J mice, but was absent in Bk2r(-/-) mice. In the presence of cycloheximide, des-Arg9-bradykinin did not cause any response at 6 h. 3. Similar findings were obtained in the urinary bladder: at 1 h des-Arg9-bradykinin (1 microM) did not cause any motor effect, whereas at 6 h it caused a contraction that was 28-59% of that produced by carbachol (1 microM) in the three mouse strains. Cycloheximide blocked the response to des-Arg9-bradykinin. Bradykinin (1 microM) contracted urinary bladders at 1 h (34-35% of carbachol), as well as at 6 h (66-77% of carbachol) in Swiss and C57B1/6J strains, but was without effect in Bk2r(-/-) mice. 4. Northern blot hybridization with a specific cDNA probe against mouse B1 receptor mRNA using total RNA extracted from tracheae and urinary bladders freshly removed from Swiss and Bk2r(-/-) mice revealed minimal expression. However, marked hybridization was detected 150 min after in vitro exposure in both tissues. 5. Evidence is provided that in vitro exposure of mouse trachea and urinary bladder causes a time-dependent induction of B1 receptors that cause relaxation and contraction, respectively.


Assuntos
Receptores da Bradicinina/genética , Traqueia/metabolismo , Bexiga Urinária/metabolismo , Animais , Northern Blotting , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor B1 da Bradicinina , Fatores de Tempo , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia
16.
Arch Ophthalmol ; 116(4): 488-91, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9565047

RESUMO

OBJECTIVE: To measure scattered laser energy reaching the posterior pole during transscleral cyclophotocoagulation. METHODS: Transscleral cyclophotocoagulation was performed on 4 cadaver eyes with Nd:YAG noncontact, Nd:YAG contact, and diode contact lasers. Energy was measured with a photodiode through a 7-mm trephined hole in the posterior pole. Average percentage power, average power, and average energy transmission were calculated. American Conference of Governmental Industrial Hygienists (ACGIH) guidelines were used to calculate allowable energy exposures for each laser. RESULTS: All 3 lasers transmitted 3% to 5% of the power to the posterior pole. The average energy transmission was 240 to 260 mJ for all lasers. The contact lasers had an average power transmission of 120 mW. The noncontact Nd:YAG laser, with shorter pulse duration, had an average power transmission of 13,000 mW, significantly greater than that of the other lasers. The ACGIH guidelines for allowable energy exposures were 93 mJ for the noncontact Nd:YAG laser, 1300 mJ for the contact Nd:YAG laser, and 440 mJ for the contact diode laser. CONCLUSIONS: Three percent to 5% of laser power delivered during cyclophotocoagulation reaches the posterior pole. Exposure energies may approach or exceed ACGIH guidelines. The clinical significance of these findings remains to be shown.


Assuntos
Corpo Ciliar/cirurgia , Fotocoagulação a Laser , Retina/efeitos da radiação , Idoso , Humanos , Fotocoagulação a Laser/efeitos adversos , Fotocoagulação a Laser/normas , Concentração Máxima Permitida , Guias de Prática Clínica como Assunto/normas , Lesões por Radiação/etiologia , Espalhamento de Radiação , Esclera , Transtornos da Visão/etiologia
17.
Arch Surg ; 122(7): 823-4, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2884983

RESUMO

Multiple visceral aneurysms complicating periarteritis nodosa are considered characteristic, though not pathognomonic, on arteriography. This arteriographic pattern has been described with hairy-cell leukemia, collagen vascular disorders, and atrial myxoma, but, to our knowledge, has not been previously reported with subacute bacterial endocarditis. A patient with enterococcal endocarditis sustained separate intra-abdominal hemorrhages, 24 hours apart, from aneurysms of the middle colic and left colic arteries. Sterile vessel cultures with inflammatory infiltrates, decreased complement levels, positive rheumatoid factor, and arteriographic evidence of multiple visceral aneurysms suggest the vasculitis was immunologically mediated and not mycotic. Antibiotic therapy after control of hemorrhage controlled abdominal symptoms.


Assuntos
Aneurisma/complicações , Endocardite Bacteriana/complicações , Artérias Mesentéricas/cirurgia , Idoso , Aneurisma/cirurgia , Morte Súbita/etiologia , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/microbiologia , Hemorragia/diagnóstico por imagem , Humanos , Laparotomia , Masculino , Artérias Mesentéricas/diagnóstico por imagem , Poliarterite Nodosa/etiologia , Radiografia , Reoperação
18.
Am J Ophthalmol ; 110(3): 300-2, 1990 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-2396656

RESUMO

Five children (three girls and two boys, aged 3 1/2 to 9 1/2 years) were referred by their pediatricians for evaluation of intermittent pulling on their eyelids. All the children were free of systemic disease. One child wore spectacles for accommodative esotropia but no child had evidence of an acute ocular disorder. The duration of symptoms before examination ranged from one to 13 months. None of the parents were able to identify temporally related stressful events. Reassurance alone was given to both parents and children; eyelid pulling resolved in all cases within two weeks. In only the youngest patient did eyelid pulling recur and no child developed other symptoms during a follow-up of six to 15 months. Following resolution, parents believed their children pulled on the eyelids to gain attention or because their eyes were initially irritated and they then developed a "bad habit." Children said they did it to "look funny" or because their "eyes were not opening enough."


Assuntos
Comportamento Infantil , Pálpebras , Atenção , Atitude Frente a Saúde , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pais
19.
Life Sci ; 64(13): PL157-63, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10210279

RESUMO

We studied the action of nociceptin (NC) on the atropine-resistant contractions of the guinea pig isolated bronchus evoked by the electrical field stimulation (EFS), an effect that is mediated by the activation of excitatory non adrenergic-non cholinergic (eNANC) nerves and the subsequent release of tachykinins. The functional site by which NC acts in this preparation was investigated using few different NC receptor agonists and the newly discovered NC receptor antagonist, [Phe1psi(CH2-NH)Gly2]NC(1-13)NH2 ([F/G]NC(1-13)NH2). NC inhibited in a concentration dependent manner (pEC50 7.14; Em - 87 +/- 3% of control values) EFS induced contractions. NC effect was mimicked by the NC analogues, NCNH2 and NC(1-13)NH2, but not by NC(1-9)NH2. NC (1 microM) did not affect the contractile effects of exogenously applied neurokinin A (1 microM). [F/G]NC(1-13)NH2 (10 microM) completely prevented the inhibition induced by NC (1 microM), whereas naloxone (1 microM) was found inactive. Both naloxone and ([F/G]NC(1-13)NH2 were per se inactive on basal resting tone as well as on the electrically induced contractions. The present findings show that NC inhibits the atropine-resistant EFS-induced contraction in the guinea pig bronchus by inhibiting eNANC nerves, and suggest the presence of NC receptors, distinct from opioid receptors, on the nerves of the guinea pig bronchus.


Assuntos
Broncoconstrição , Receptores Opioides/fisiologia , Receptores de Taquicininas/fisiologia , Animais , Brônquios/inervação , Estimulação Elétrica , Feminino , Cobaias , Técnicas In Vitro , Masculino , Neurocinina A/farmacologia , Substância P/farmacologia , Receptor de Nociceptina
20.
Am Surg ; 57(5): 301-5, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2039128

RESUMO

A startling 31 per cent rate of perforated appendicitis in 1984 prompted a 5-year review at the Guthrie Medical Center. An increase over previous rates of 13 per cent and 0 per cent in 1964 and 1944 was confirmed in this study. Perforation accompanied 44 of 240 cases of appendicitis (18.3%); diagnostic accuracy in 295 cases undergoing operation was 81.4 per cent. Groups at risk for perforation were patients in the first decade of life (34.3% with perforations) and those over 50 years of age (48% perforated). Perforation rates were generally inversely related to accuracy. Accuracy was poorest in women in the second to fourth decade or those in the mid-portion of the menstrual cycle. When the appendix was not perforated, complications occurred in 8.7 per cent of patients while 29.5 per cent with a perforation had a complication. The mean hospital stay was prolonged by 2.5 days if the appendix was perforated. An increased awareness of the risk by both the public and physicians is essential to reduce the number of perforations.


Assuntos
Apendicite/epidemiologia , Perfuração Intestinal/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apendicectomia/efeitos adversos , Apendicite/complicações , Apendicite/patologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Perfuração Intestinal/complicações , Perfuração Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Pennsylvania/epidemiologia , Peritonite/etiologia , Ruptura Espontânea
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA