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1.
J Pers Assess ; 106(3): 361-371, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37594306

RESUMO

Moral Foundations Theory proposes that five innate modules offer an intuitive response that drives our moral judgments. Various instruments were developed to measure the five moral foundations, including the MFV and the MFQ-30 which focus on deliberative moral reasoning. This approach is limited because intuitions are more basic and affect-laden. The Moral Foundations Sacredness Scale (MFSS) was designed to elicit responses that more closely resemble these phenomena. However, studies have not converged on a factorial structure for the MFSS, and measurement invariance has never been assessed. Our study sought to evaluate these properties across four adult samples, via Exploratory Structural Equation Modeling, and the associations between the MFSS's scales and relevant constructs. We found that a two-factor solution, reflecting the individualizing and binding foundations, had a reasonable fit, and had invariance (configural, metric, and scalar) across gender, age groups, and (configural) four international samples. The scales were reliable, had construct validity with the MFQ-30, and criterion-related validity with the binding moderately predicting belief in God/spirit and religious behaviors. The convergence we found regarding the MFSS's factorial structure across groups has important implications for the dimensionality of these constructs, and - ultimately - for the development of Moral Foundations Theory.


Assuntos
Julgamento , Princípios Morais , Adulto , Humanos , Resolução de Problemas
2.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13766-13777, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37467087

RESUMO

Millions of papers are submitted and published every year, but researchers often do not have much information about the journals that interest them. In this paper, we introduced the first dynamical clustering algorithm for symbolic polygonal data and this was applied to build scientific journals profiles. Dynamic clustering algorithms are a family of iterative two-step relocation algorithms involving the construction of clusters at each iteration and the identification of a suitable representation or prototype (means, axes, probability laws, groups of elements, etc.) for each cluster by locally optimizing an adequacy criterion that measures the fitting between clusters and their corresponding prototypes The application gives a powerful vision to understand the main variables that describe journals. Symbolic polygonal data can represent summarized extensive datasets taking into account variability. In addition, we developed cluster and partition interpretation indices for polygonal data that have the ability to extract insights about clustering results. From these indices, we discovered, e.g., that the number of difficult words in abstract is fundamental to building journal profiles.

3.
J Pers Assess ; 105(1): 22-33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35298310

RESUMO

The Schwartz Model of Basic Values is an influential framework that describes what people find important and worth pursuing in life. The model proposes that ten human values are found cross-culturally, and so significant efforts have gone into empirically testing these claims. While instruments such as the Portrait Values Questionnaire-40 (PVQ-40) reliably discriminated the full set of theorized values, briefer versions have either suffered from a lack of construct validity (PVQ-21) or from not having been put through a rigorous statistical test of its underlying structure (Twenty Item Values Inventory [TwIVI]) via confirmatory factor analysis (CFA). The present study, using a Portuguese sample of adults (n = 524), is the first to examine the factorial structure of the TwIVI via CFA. We apply a magnifying glass approach by testing two separate models, each covering five values, which reflect the Growth and Self-protective dimensions. Moreover, we provide evidences that the TwIVI is reliable and capable of capturing the theorized quasi-circumplex structure, and the cross-cultural gender differences and relative hierarchical importance of values. Finally, we establish criterion-related validity, with values correlating with political identity and social and economic issues.


Assuntos
Reprodutibilidade dos Testes , Adulto , Humanos , Portugal , Inquéritos e Questionários , Análise Fatorial , Psicometria
4.
Anticancer Agents Med Chem ; 22(18): 3163-3171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692152

RESUMO

BACKGROUND: Calotropis procera is a laticiferous plant (Apocynaceae) found in tropical regions all over the world. The ultrastructural characteristics of laticifers, their restricted distribution among different taxonomic groups, and in some species in each clade, as peptidases from latex, make them very attractive for biological analysis. OBJECTIVE: The study aims to investigate the effects of LP-PII-IAA (laticifer protein (LP) sub-fraction II (PII) of C. procera presenting an iodoacetamide-inhibited cysteine proteinase activity) on irinotecan-induced intestinal mucositis, a serious adverse effect of this medicine for the treatment of cancer. METHODS: LP-PII-IAA is composed of closely related isoforms (90%) of peptidases derived from catalysis and an osmotin protein (5%). Animals receiving co-administration of LP-PII-IAA presented a significant decrease in mortality, absence of diarrhea, histological preservation, and normalization of intestinal functions. RESULTS: Clinical homeostasis was accompanied by a reduction in MPO activity and declined levels of IL-1ß, IL-6 and KC, while the IL-10 level increased in LP-PII-IAA-treated animals. COX-2 and NF-kB immunostaining was reduced and the levels of oxidative markers (GSH, MDA) were normalized in animals that received LP-PII-IAA. CONCLUSION: We suggest that peptidases from the latex of Calotropis procera were instrumental in the suppression of the adverse clinical and physiological effects of irinotecan.


Assuntos
Calotropis , Cisteína Proteases , Animais , Calotropis/química , Ciclo-Oxigenase 2 , Interleucina-10 , Interleucina-6 , Iodoacetamida , Irinotecano/farmacologia , Látex/química , Látex/farmacologia , NF-kappa B , Proteínas de Plantas/farmacologia , Proteínas de Plantas/uso terapêutico
5.
J Med Virol ; 94(9): 4170-4180, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35535440

RESUMO

We adopted the reverse-transcriptase-loop-mediated isothermal amplification (RT-LAMP) to detect severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) in patient samples. Two primer sets for genes N and Orf1ab were designed to detect SARS-CoV-2, and one primer set was designed to detect the human gene Actin. We collected prospective 138 nasopharyngeal swabs, 70 oropharyngeal swabs, 69 salivae, and 68 mouth saline wash samples from patients suspected to have severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 to test the RT-LAMP in comparison with the gold standard technique reverse-transcription quantitative polymerase chain reaction  (RT-qPCR). The accuracy of diagnosis using both primers, N5 and Orf9, was evaluated. Sensitivity and specificity for diagnosis were 96% (95% confidence interval [CI]: 87-99) and 85% (95% CI: 76-91) in 138 samples, respectively. Accurate diagnosis results were obtained only in nasopharyngeal swabs processed via extraction kit. Accurate and rapid diagnosis could aid coronavirus disease 2019 (COVID-19) pandemic management by identifying, isolating, and treating patients rapidly.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil , COVID-19/diagnóstico , Teste para COVID-19 , Técnicas de Laboratório Clínico/métodos , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Estudos Prospectivos , RNA Viral/genética , SARS-CoV-2/genética , Sensibilidade e Especificidade
6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21264242

RESUMO

This study aimed to evaluate the efficacy and toxicity of tenofovir (TDF) and TDF combined with emtricitabine (TDF/FTC) in patients with mild to moderate COVID-19 infections. We conducted a randomized, double-blind, placebo-controlled clinical trial in patients with clinical suspicion of mild to moderate respiratory infection caused by SARS-CoV-2 who were treated at an outpatient clinic. Patients were randomly recruited to take 10 days of TDF (300 mg/day), TDF (300 mg/day) combined with FTC (200 mg/day) or placebo Vitamin C (500 mg/day). The primary parameter was the score of symptoms and predictive signs of COVID-19, assessed on the seventh day of patient follow-up. From a total of 309 patients with clinical suspicion of SARS-CoV-2, 227 met the inclusion criteria and were randomly distributed into the following groups: (a) 75 (one did not initiate treatment) in the TDF group; (b) 74 in the TDF combined with FTC group; and (c) 77 in the Vitamin C group (placebo). Of the 226 patients, 139 (62%) were positive for SARS-CoV-2. Fever ([≥]37.8{degrees}C), ageusia or dysgeusia, anosmia or dysosmia, and two or more clinical symptoms or signs were significantly associated with SARS-CoV-2 infection. There was no significant change in clinical score based on clinical symptoms and signs between treatment groups. Patients with mild to moderate infection by SARS-CoV-2 had higher concentrations of G-CSF, IL-1{beta}, IL-6 and TNF- compared to patients without infection. Patients with mild to moderate respiratory infection, with fever ([≥]37.8{degrees}C), loss of smell, loss of taste and two or more symptoms, have a better prediction for the diagnosis of COVID-19. Patients with SARS-CoV-2 showed higher and more persistent proinflammatory cytokines profile compared to patients not infected with SARS-CoV-2. Pharmacological intervention with TDF or TDF combined with FTC did not change the clinical signs and symptoms score in mild to moderate respiratory infection in patients with SARS-CoV-2 compared to the Vitamin C group (placebo).

7.
Biochem Pharmacol ; 186: 114500, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33684388

RESUMO

The angiotensin (Ang) II converting enzyme (ACE II) pathway has recently been shown to be associated with several beneficial effects on the body, especially on the cardiac system and gastrointestinal tract. ACE II is responsible for converting Ang II into the active peptide Ang-(1-7), which in turn binds to a metabotropic receptor, the Mas receptor (MasR). Recent studies have demonstrated that Diminazene Aceturate (DIZE), a trypanosomicide used in animals, activates the ACE II pathway. In this study, we aimed to evaluate the antidiarrheal effects promoted by the administration of DIZE to activate the ACE II/Ang-(1-7)/MasR axis in induced diarrhea mice models. The results show that activation of the ACE II pathway exerts antidiarrheal effects that reduce total diarrheal stools and enteropooling. In addition, it increases Na+/K+-ATPase activity and reduces gastrointestinal transit and thus inhibits contractions of intestinal smooth muscle; decreases transepithelial electrical resistance, epithelial permeability, PGE2-induced diarrhea, and proinflammatory cytokines; and increases anti-inflammatory cytokines. Enzyme-linked immunosorbent assay (ELISA) demonstrated that DIZE, when activating the ACE II/Ang-(1-7)/MasR axis, can still interact with GM1 receptors, which reduces cholera toxin-induced diarrhea. Therefore, activation of the ACE II/Ang-(1-7)/MasR axis can be an important pharmacological target for the treatment of diarrheal diseases.


Assuntos
Angiotensina II/metabolismo , Angiotensina I/metabolismo , Antidiarreicos/uso terapêutico , Diarreia/metabolismo , Diminazena/análogos & derivados , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Antidiarreicos/farmacologia , Óleo de Rícino/toxicidade , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Diminazena/farmacologia , Diminazena/uso terapêutico , Relação Dose-Resposta a Droga , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Masculino , Camundongos , Proto-Oncogene Mas , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia
8.
Med Hypotheses ; 143: 109886, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32504925

RESUMO

Coronavirus disease 2019 (COVID-19) is an infectious disease with fast spreading all over the world caused by the SARS-CoV-2 virus which can culminate in a severe acute respiratory syndrome by the injury caused in the lungs. However, other organs can be also damaged. SARS-CoV-2 enter into the host cells using the angiotensin-converting enzyme 2 (ACE2) as receptor, like its ancestor SARS-CoV. ACE2 is then downregulated in lung tissues with augmented serum levels of ACE2 in SARS-CoV-2 patients. Interestingly, ACE2+ organs reveal the symptomatic repercussions, which are signals of the infection such as dry cough, shortness of breath, heart failure, liver and kidney damage, anosmia or hyposmia, and diarrhea. ACE2 exerts a chief role in the renin-angiotensin system (RAS) by converting angiotensin II to angiotensin-(1-7) that activates Mas receptor, inhibits ACE1, and modulates bradykinin (BK) receptor sensitivity, especially the BK type 2 receptor (BKB2R). ACE2 also hydrolizes des-Arg9-bradykinin (DABK), an active BK metabolite, agonist at BK type 1 receptors (BKB1R), which is upregulated by inflammation. In this opinion article, we conjecture a dialogue by the figure of Sérgio Ferreira which brought together basic science of classical pharmacology and clinical repercussions in COVID-19, then we propose that in the course of SARS-CoV-2 infection: i) downregulation of ACE2 impairs the angiotensin II and DABK inactivation; ii) BK and its metabolite DABK seems to be in elevated levels in tissues by interferences in kallikrein/kinin system; iii) BK1 receptor contributes to the outbreak and maintenance of the inflammatory response; iv) kallikrein/kinin system crosstalks to RAS and coagulation system, linking inflammation to thrombosis and organ injury. We hypothesize that targeting the kallikrein/kinin system and BKB1R pathway may be beneficial in SARS-CoV-2 infection, especially on early stages. This route of inference should be experimentally verified by SARS-CoV-2 infected mice.


Assuntos
Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Sistema Calicreína-Cinina/fisiologia , Modelos Biológicos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Enzima de Conversão de Angiotensina 2 , Animais , COVID-19 , Infecções por Coronavirus/etiologia , Humanos , Sistema Calicreína-Cinina/efeitos dos fármacos , Camundongos , Pandemias , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/etiologia , Receptores Virais/fisiologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia , SARS-CoV-2 , Pesquisa Translacional Biomédica , Internalização do Vírus/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
9.
Pharmaceuticals (Basel) ; 13(1)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963683

RESUMO

Anadenanthera colubrina var. cebil (Griseb.) Altschul (Fabaceae family), commonly known as the red angico tree, is a medicinal plant found throughout Brazil's semi-arid area. In this study, a chemical analysis was performed to investigate the antidiarrheal activity and safety profile of red angico gum (RAG), a biopolymer extracted from the trunk exudate of A. colubrina. Upon FT-IR spectroscopy, RAG showed bands in the regions of 1608 cm-1, 1368 cm-1, and 1029 cm-1, which relate to the vibration of O-H water molecules, deformation vibration of C-O bands, and vibration of the polysaccharide C-O band, respectively, all of which are relevant to glycosidic bonds. The peak molar mass of RAG was 1.89 × 105 g/mol, with the zeta potential indicating electronegativity. RAG demonstrated high yield and solubility with a low degree of impurity. Pre-treatment with RAG reduced the total diarrheal stool and enteropooling. RAG also enhanced Na+/K+-ATPase activity and reduced gastrointestinal transit, and thereby inhibited intestinal smooth muscle contractions. Enzyme-Linked Immunosorbent Assay (ELISA) demonstrated that RAG can interact with GM1 receptors and can also reduce E. coli-induced diarrhea in vivo. Moreover, RAG did not induce any signs of toxicity in mice. These results suggest that RAG is a possible candidate for the treatment of diarrheal diseases.

10.
Eur J Pharmacol ; 806: 52-58, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28392466

RESUMO

2-Nitro-1-phenyl-1-propanol (NPP) is a nitro alcohol with vasodilator activity in the rat aorta. The present study investigated the vasodilator properties of NPP in small vessels of the mesenteric bed, which, contrary to the aorta, contains resistance vessels. Using myography, isometric contractions were recorded in rings of second- and third-order branches from the rat mesenteric artery. NPP relaxed mesenteric ring preparations that were contracted with phenylephrine, U-46619, and KCl (40mM), resulting in significantly different EC50 values (0.41µM [0.31-0.55µM], 0.16µM [0.10-0.24µM], and 4.50µM [1.86-10.81µM], respectively). NPP-induced vasodilation decreased as the extracellular K+ concentration increased. The pharmacological blockade of K+ channels with tetraethylammonium, BaCl2, CsCl, and apamin also blunted NPP-induced vasorelaxation. In contrast, NPP-induced vasodilation was resistant to indomethacin, L-NG-nitroarginine methyl ester (L-NAME), and endothelium removal, indicating that neither prostaglandins nor the endothelial release of nitric oxide is involved in the relaxant effects of NPP. Conversely, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), cis-N-(2-phenylcyclopentyl)-azacyclotridec-1-en-2-amine hydrochloride (MDL-12,330A), and H-89 reduced NPP-induced vasodilation. Under Ca2+-free conditions, NPP did not alter transient contractions that were evoked by caffeine, but it reduced transient contractions that were evoked by phenylephrine. In mesenteric rings that were loaded with the fluorescent Ca2+ indicator Fluo-4 AM and stimulated with phenylephrine, NPP blunted both contractions and fluorescence signals that were related to cytosolic Ca2+ levels. In conclusion, the vasodilatory actions NPP on mesenteric vessel resistance involved the participation of cyclic nucleotides and the opening of K+ channels.


Assuntos
Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Nitrocompostos/farmacologia , Propanóis/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Cálcio/metabolismo , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Guanilato Ciclase/metabolismo , Masculino , Artérias Mesentéricas/citologia , Artérias Mesentéricas/metabolismo , Fenilefrina/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Ratos , Ratos Wistar
11.
J Pharm Pharmacol ; 69(6): 722-732, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28211571

RESUMO

OBJECTIVE: Justicia pectoralis is a plant useful for the treatment of respiratory diseases. Here, we studied the antiasthmatic properties of a standardized extract of J. pectoralis (Jp). METHODS: Ovalbumin (OVA)-sensitized rats were actively challenged with saline or OVA to study airway hyper-responsiveness after oral treatment with saline or Jp. The ability of Jp to inhibit hyper-reactivity was evaluated in isolated trachea mounted in isolated organ bath chamber. KEY FINDINGS: Using KCl or carbachol as contractile agents, tracheal rings of OVA-challenged rats contracted with higher magnitude than trachea of rats challenged with saline. Such hyper-responsive phenotype of OVA-challenged tissues decreased with Jp administration. In Ca+ -free medium, Jp or its major constituent coumarin inhibited preferentially the contractions induced by Ca2+ addition in tissues of OVA-challenged rats stimulated with KCl or acetylcholine. In tissues depleted of their internal Ca+ stores in the presence of thapsigargin, Jp inhibited the contraction induced by capacitative Ca2+ entry. By gavage, Jp abolished the increase caused by challenge with OVA on the levels of IL-1ß and TNF-α in the bronchoalveolar fluid and also impaired the changes in gene expression of canonical transient receptor proteins. CONCLUSIONS: Jp has antiasthmatic properties in an experimental model that reproduces tracheal hyper-reactivity.


Assuntos
Justicia/química , Extratos Vegetais/farmacologia , Hipersensibilidade Respiratória/tratamento farmacológico , Animais , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/metabolismo , Líquido da Lavagem Broncoalveolar/química , Cálcio/metabolismo , Carbacol , Masculino , Modelos Animais , Ovalbumina/farmacologia , Ratos , Ratos Wistar , Hipersensibilidade Respiratória/induzido quimicamente , Hipersensibilidade Respiratória/metabolismo , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
ROBRAC ; 24(71): 201-203, 20150000. ilus
Artigo em Português | LILACS | ID: biblio-836753

RESUMO

O desarranjo interno da articulação temporo mandibular acomete cerca de 30% da população, sendo que apenas 5% requerem algum tipo de intervenção cirúrgica. A discectomia tem sido empregada quando o disco encontra-se comprometido estruturalmente, deslocado, na dor secundária em desarranjos com estágio avançado (Wilks IV e V) ou na permanência da disfunção após cirurgia prévia de reposicionamento do disco, artroscopia/artrocentese e condilectomia. Considerando-se que o sucesso no tratamento cirúrgico da articulação temporo mandibular diminui com o aumento no número de procedimentos prévios e que o reposicionamento cirúrgico do disco articular não tem se mostrado tão efetivo em longo prazo, estudos recentes têm mostrado que a discectomia tem sido o procedimento cirúrgico com maior probabilidade de sucesso e com menor morbidade quando indicado como primeira opção terapêutica.


The internal derangement of the temporomandibular affects about 30% of the population, and only 5% require some kind surgery. The most frequent indication currently published for discectomys pain secondary to late-stage internal derangement (Wilkes stages IV to V), in which the degrees of disc deformity, degeneration, or displacement, and the inelasticity of the anterior attachment, precludeits successful surgical repositioning. Another indication includes discectomy after failed surgical disc repositioning, arthroscopy. Considering that disc repositioning and disc replacement surgery have not been shown to be effective long term, and that the eventual fate of most operated joints is discectomy, then the selection of the surgical procedure with the highest probability of success and the least morbidity should be considered primarily. The aim of this article is show a case report of a female pacient that fail a conservative treatment with occlusal splint and Arthrocentesis, being subjected to discectomy for treatment of internal derangements.

13.
J Urol ; 194(6): 1777-86, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26220217

RESUMO

PURPOSE: Hemorrhagic cystitis is an important dose limiting side effect of ifosfamide based cancer chemotherapy. Despite chemoprophylaxis inflammation can still be found in cystoscopy guided biopsies. Previous studies confirmed the role of TNF-α and IL-1ß. We evaluated the protective effect of the IL-1R antagonist anakinra and the anti-TNF-α antibody infliximab in experimental ifosfamide induced hemorrhagic cystitis. MATERIALS AND METHODS: Hemorrhagic cystitis was induced by an injection of ifosfamide (400 mg/kg intraperitoneally) in Swiss wild-type C57Bl/6, IL-1R-/-, TNFR1-/- or TNFR1/R2-/- mice. Mice were treated 30 minutes before ifosfamide with anakinra (100 mg/kg intraperitoneally), infliximab (5 mg/kg intraperitoneally) or vehicle. Visceral nociception was evaluated after hemorrhagic cystitis induction. At 12 hours the animals were sacrificed. Bladders were harvested to assess bladder wet weight, vascular permeability, macroscopic and microscopic findings, muscle contractility, and for cystometrography. Inflammatory cell infiltration was assessed by myeloperoxidase assay and flow cytometry. RESULTS: Anakinra attenuated hemorrhage, edema, neutrophil infiltration, visceral hyperalgesia and bladder dysfunction. IL-1R-/- mice also showed milder hemorrhagic cystitis. Infliximab inhibited bladder edema and visceral hyperalgesia without preventing hemorrhage, bladder dysfunction, neutrophils or accumulation. Additionally, the lack of TNFR1 decreased bladder edema but not cell infiltration whereas concomitant deficiency of TNFR1 and TNFR2 resulted in worse hemorrhagic cystitis. CONCLUSIONS: Anakinra is effective for preventing experimentally ifosfamide induced hemorrhagic cystitis. It seems that neutrophil and macrophage infiltration in this circumstance depends on IL-1 signaling through IL1R. Possibly TNFR2 has a protective role in hemorrhagic cystitis.


Assuntos
Cistite/induzido quimicamente , Cistite/prevenção & controle , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Ifosfamida/toxicidade , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Receptores de Interleucina-1/antagonistas & inibidores , Animais , Cistite/patologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Hemorragia/patologia , Infliximab/farmacologia , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia
14.
Biochem Pharmacol ; 91(2): 191-201, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25107700

RESUMO

The nitroderivative 1-nitro-2-phenylethane (NPE) was recently described as a compound possessing heme-dependent soluble guanylyl cyclase (sGC) stimulating properties in vascular smooth muscle cells. In this study, we tested such pharmacological property of NPE in mice pancreatic acinar cells subjected to the bile salt taurocholate, a type of pathological stimulus that simulates pancreatitis. Here, isolated acinar cells were treated with NPE in order to assess the role of sGC on the detrimental effects induced by taurocholate. NPE reduced taurocholate-elicited Ca(2+) overload, production of reactive oxygen species (ROS), apoptosis, necrosis, and exerted a protective effect against mitochondrial membrane potential (ΔΨm) dissipation. These NPE-induced effects were abolished by pretreatment with ODQ and KT 5823, and after the blockade of nitric oxide (NO) synthase with l-NAME, inhibitors of key components of the sGC pathway. Contrarily to cGMP that alone increased ΔΨm collapse and cell damage, the cytoprotective effect of NPE on ΔΨm and cell necrosis was almost reproduced by 8-nitro-cGMP, a second messenger generated by sGC under oxidative stress conditions. In conclusion, putative sGC stimulation with NPE reveals its cytoprotective profile on pancreatic cells subjected to taurocholate. Moreover, ROS and NO conjunctly appear to drive sGC activity in pancreatic acinar cells to implement an adaptive mechanism in response to oxidative and Ca(2+) stress through 8-nitro-cGMPsynthesis.


Assuntos
Células Acinares/efeitos dos fármacos , Derivados de Benzeno/farmacologia , GMP Cíclico/análogos & derivados , Pâncreas/citologia , Ácido Taurocólico/toxicidade , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Células Cultivadas , GMP Cíclico/metabolismo , Masculino , Camundongos , Necrose , Pâncreas/efeitos dos fármacos , Espécies Reativas de Oxigênio
15.
Eur J Pharmacol ; 740: 192-9, 2014 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-25046838

RESUMO

Methyl cinnamate (MC) is a safe flavoring agent useful to food industry. Although chemically analog to tyrosine kinase inhibitors, there is little information regarding its biological actions. Here, we aimed at assessing the MC effects on gastrointestinal contractility and the putative involvement of tyrosine kinase in the mediation of these effects. Isometric contractions were recorded in rat isolated strips from stomach, duodenum and colon segments. In gastric strips, MC (3-3000 µM) showed antispasmodic effects against carbachol-induced contractions, which remained unchanged by either l-NAME or tetraethylammonium pretreatment and occurred with potency similar to that obtained against contractions evoked by potassium or U-46619. In colon strips, MC was four times more potent than in gastric ones. MC and the positive control genistein inhibited phasic contractions induced by acetylcholine in Ca2+-free medium, an effect fully prevented by sodium orthovanadate. Both MC and genistein decreased the spontaneous contractions of duodenal strips and shortened the time necessary for gastric fundic tissues to reach 50% of maximal relaxation. In freshly isolated colon myocytes, MC decreased the basal levels of cytoplasmic Ca2+, but not the potassium-elicited cytoplasmic Ca2+ elevation. Colon strips obtained from rats subjected to intracolonic acetic acid instillation showed reduced contractility to potassium, which was partially recovered in MC-treated rats. Inhibitory effect of nifedipine against cholinergic contractions, blunted in acetic acid-induced colitis, was also recovered in MC-treated rats. In conclusion, MC inhibited the gastrointestinal contractility with a probable involvement of tyrosine kinase pathways. In vivo, it was effective to prevent the deleterious effects of colitis resulting from acetic acid injury.


Assuntos
Cinamatos/farmacologia , Colo/efeitos dos fármacos , Duodeno/efeitos dos fármacos , Aromatizantes/farmacologia , Parassimpatolíticos/farmacologia , Estômago/efeitos dos fármacos , Ácido Acético , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Carbacol , Cinamatos/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/fisiopatologia , Colo/fisiologia , Duodeno/fisiologia , Aromatizantes/uso terapêutico , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Nifedipino/farmacologia , Parassimpatolíticos/uso terapêutico , Cloreto de Potássio/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/fisiologia , Ratos Wistar , Estômago/fisiologia
16.
J Appl Physiol (1985) ; 116(9): 1133-41, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24557800

RESUMO

Physical exercise, mainly after vigorous activity, may induce gastrointestinal dysmotility whose mechanisms are still unknown. We hypothesized that physical exercise and ensuing lactate-related acidemia alter gastrointestinal motor behavior. In the present study, we evaluated the effects of short-term exercise on gastric emptying rate in awake rats subjected to 15-min swimming sessions against a load equivalent to 5% of their body weight. After 0, 10, or 20 min of exercise testing, the rats were gavage fed with 1.5 ml of a liquid test meal (0.5 mg/ml of phenol red in 5% glucose solution) and euthanized 10 min postprandially to measure fractional gastric dye recovery. In addition to inducing acidemia and increasing blood lactate levels, acute exercise increased (P < 0.05) gastric retention. Such a phenomenon presented a positive correlation (P < 0.001) between blood lactate levels and fractional gastric dye recovery. Gastric retention and other acidbase-related changes were all prevented by NaHCO3 pretreatment. Additionally, exercise enhanced (P < 0.05) the marker's progression through the small intestine. In anesthetized rats, exercise increased (P < 0.05) gastric volume, measured by a balloon catheter in a barostat system. Compared with sedentary control rats, acute exercise also inhibited (P < 0.05) the contractility of gastric fundus strips in vitro. In conclusion, acute exercise delayed the gastric emptying of a liquid test meal by interfering with the acid-base balance.


Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Esvaziamento Gástrico/fisiologia , Condicionamento Físico Animal/fisiologia , Bicarbonato de Sódio/farmacologia , Vigília/fisiologia , Animais , Masculino , Condicionamento Físico Animal/métodos , Ratos , Ratos Wistar , Fatores de Tempo , Resultado do Tratamento , Vigília/efeitos dos fármacos
17.
Am J Physiol Heart Circ Physiol ; 304(10): H1397-405, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23504183

RESUMO

Arteriovenous anastomoses disrupt cardiovascular and renal homeostasis, eliciting hemodynamic adjustments, resetting the humoral pattern, and inducing cardiac hypertrophy. Because acute circulatory imbalance alters gut motor behavior, we studied the effects of arteriovenous fistula placement on the gastric emptying (GE) of a liquid meal in awake rats. After laparotomy, we created an aortocaval fistula (ACF) by aorta and cava wall puncture with a 21-, 23-, or 26-gauge needle. The ACF was not created in the control group, which underwent sham operation. After 12, 24, or 48 h, mean arterial pressure, heart rate, and central venous pressure were continuously recorded, and cardiac output was estimated by thermal dilution. The rats were then gavage fed a test meal (i.e., phenol red in glucose solution), and fractional dye retention was determined 10, 20, or 30 min later. The effect of prior bleeding on ACF-induced GE delay, the role of neuroautonomic pathways, and changes in plasma hormone levels (i.e., angiotensin II, arginine vasopressin, atrial natriuretic peptide, corticosterone, and oxytocin) were evaluated. When compared with the sham-operated group, ACF rats exhibited arterial hypotension, higher (P < 0.05) heart rate, central venous pressure, and cardiac output values and increased (P < 0.05) gastric dye retention, a phenomenon prevented by bilateral subdiaphragmatic vagotomy and hexamethonium treatment. Pirenzepine also impaired the occurrence of gastric delay in subjects with ACF. In addition to causing hyperkinetic circulation, ACF placement delayed the GE of liquid in awake rats, an effect that likely involves a parasympathetic pathway.


Assuntos
Aorta Abdominal , Fístula Arteriovenosa/fisiopatologia , Esvaziamento Gástrico/fisiologia , Veia Cava Inferior , Animais , Sistema Nervoso Autônomo/fisiologia , Gasometria , Débito Cardíaco , Eletrodos Implantados , Ganglionectomia , Trânsito Gastrointestinal/fisiologia , Hormônios/sangue , Laparotomia , Masculino , Vias Neurais/fisiologia , Ratos , Ratos Wistar , Receptores Nicotínicos/fisiologia , Vagotomia
18.
J Pediatr Surg ; 48(2): 326-32, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23414860

RESUMO

BACKGROUND/PURPOSE: The mechanism of fetal gastric dilation in gastroschisis is controversial. This study was designed to characterize changes in the contractile profile of strips of stomach from rats following experimental gastroschisis. METHODS: Pregnant Wistar rats were operated on day 18.5. Fetuses were divided into three groups: gastroschisis (G), sham (S), and control (C). On day 21.5, gastric fundus and antrum strips were obtained and suspended to a force transducer connected to a digital data acquisition system. They were submitted to increasing concentrations of carbachol (CCh) and weighed at the end of each procedure. Frequency and amplitude of each contraction were evaluated. RESULTS: Under basal conditions, spontaneous oscillatory contractions of antrum and fundus strips of G, S, and C were similar (P>0.05; ANOVA). However, cumulative concentrations of CCh (0.01-100 µM) produced different effects in all groups and were characterized by a significant increase in amplitude and frequency of spontaneous contractions in antral smooth muscle and a sustained increase in tonus in fundic strips. Upon analysis, no significant difference in frequency or amplitude was noted in antral tissues comparing C to G and to S (P>0.05). No significant contractility difference was noted in fundic smooth muscle (comparing all groups, P>0.05), with the CCh-induced curve following a typical sigmoidal format, dependent on increasing concentrations (P<0.001). CONCLUSIONS: Gastric contractile responses to CCh are preserved in experimental gastroschisis. These results do not support the theory that gastric dilation occurs secondary to intestinal inflammation alone.


Assuntos
Gastrosquise/embriologia , Gastrosquise/fisiopatologia , Contração Muscular , Animais , Modelos Animais de Doenças , Técnicas In Vitro , Ratos , Ratos Wistar
19.
Biochem Pharmacol ; 85(6): 780-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23270994

RESUMO

1-Nitro-2-phenylethane is the first organic NO2-containing molecule isolated from plants. It possesses interesting hypotensive, bradycardic, and vasodilator properties, but the mode by which it induces vasorelaxation is still unknown. The underlying mechanism involved in the vasodilator effect of 1-nitro-2-phenylethane was investigated in rat aorta. The vasorelaxant effects of 1-nitro-2-phenylethane did not depend on endothelial layer integrity, and the effects were refractory to L-N(G)-nitroarginine methyl ester (L-NAME)-induced nitric oxide synthase inhibition. Vasorelaxation was similarly resistant to treatment with indomethacin, cis-N-(2-phenylcyclopentyl)-azacyclotridec-1-en-2-amine hydrochloride (MDL-12330A), and KT5720, indicating that neither prostaglandin release nor adenylyl cyclase activation is involved. Conversely, methylene blue- and ODQ-induced guanylate cyclase inhibition reduced the vasorelaxation induced by 1-nitro-2-phenylethane. The pharmacological blockade of K(+) channels with tetraethylammonium, glybenclamide, and 4-aminopyridine also blunted vasorelaxation induced by 1-nitro-2-phenylethane. The effects of 1-nitro-2-phenylethane were reversed by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and comparable to the effects induced by sodium nitroprusside. In silico analysis using an Ns H-NOX subunit of guanylate cyclase revealed a pocket on the macromolecule surface where 1-nitro-2-phenylethane preferentially docked. In vitro, 1-nitro-2-phenylethane increased cyclic guanosine 3',5'-monophosphate (cGMP) levels in rat aortic rings, an effect also reversed by ODQ. In conclusion, 1-nitro-2-phenylethane produces vasodilator effects by stimulating the soluble guanylate cyclase-cGMP pathway.


Assuntos
Derivados de Benzeno/farmacologia , GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Vasodilatadores/farmacologia , Animais , Masculino , Ratos , Ratos Wistar , Guanilil Ciclase Solúvel
20.
Can J Physiol Pharmacol ; 90(1): 23-35, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22171824

RESUMO

The present study deals with the pharmacological effects of the sesquiterpene alcohol (-)-α-bisabolol on various smooth-muscle preparations from rats. Under resting tonus, (-)-α-bisabolol (30-300 µmol/L) relaxed duodenal strips, whereas it showed biphasic effects in other preparations, contracting endothelium-intact aortic rings and urinary bladder strips, and relaxing these tissues at higher concentrations (600-1000 µmol/L). In preparations precontracted either electromechanically (by 60 mmol/L K(+)) or pharmacomechanically (by phenylephrine or carbachol), (-)-α-bisabolol showed only relaxing properties. The pharmacological potency of (-)-α-bisabolol was variable, being higher in mesenteric vessels, whereas it exerted relaxing activity with a lesser potency on tracheal or colonic tissues. In tissues possessing spontaneous activity, (-)-α-bisabolol completely decreased spontaneous contractions in duodenum, whereas it increased their amplitude in urinary bladder tissue. Administered in vivo, (-)-α-bisabolol attenuated the increased responses of carbachol in tracheal rings of ovalbumin-sensitized rats challenged with ovalbumin, but was without effect in the decreased responsiveness of urinary bladder strips in mice treated with ifosfamide. In summary, (-)-α-bisabolol is biologically active in smooth muscle. In some tissues, (-)-α-bisabolol preferentially relaxed contractions induced electromechanically, especially in tracheal smooth muscle. The findings from tracheal rings reveal that (-)-α-bisabolol may be an inhibitor of voltage-dependent Ca(2+) channels.


Assuntos
Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Carbacol/antagonistas & inibidores , Carbacol/farmacologia , Cistite/induzido quimicamente , Cistite/tratamento farmacológico , Modelos Animais de Doenças , Duodeno/efeitos dos fármacos , Duodeno/fisiologia , Ifosfamida , Técnicas In Vitro , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Masculino , Sesquiterpenos Monocíclicos , Contração Muscular/fisiologia , Relaxamento Muscular/fisiologia , Músculo Liso/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Ovalbumina , Fenilefrina/farmacologia , Ratos , Ratos Wistar , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologia
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