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1.
Behav Brain Res ; 379: 112393, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31785362

RESUMO

Cognitive flexibility, shown to be impaired in patients presenting with compulsions, is dependent on balanced dopaminergic and serotonergic interaction. Towards the development of a zebrafish (Danio rerio) screening test for anti-compulsive drug action, we manipulated social reward appraisal under different contexts by means of dopaminergic (apomorphine) and serotonergic (escitalopram) intervention. Seven groups of zebrafish (n = 6 per group) were exposed for 24 days (1 h per day) to either control (normal tank water), apomorphine (50 or 100 µg/L), escitalopram (500 or 1000 µg/L) or a combination (A100/E500 or A100/E1000 µg/L). Contextual reward appraisal was assessed over three phases i.e. Phase 1 (contingency association), Phase 2 (dissociative testing), and Phase 3 (re-associative testing). We demonstrate that 1) sight of social conspecifics is an inadequate motivational reinforcer under circumstances of motivational conflict, 2) dopaminergic and serotonergic intervention lessens the importance of an aversive stimulus, increasing the motivational valence of social reward, 3) while serotoninergic intervention maintains reward directed behavior, high-dose dopaminergic intervention bolsters cue-directed responses and 4) high-dose escitalopram reversed apomorphine-induced behavioral inflexibility. The results reported here are supportive of current dopamine-serotonin opponency theories and confirm the zebrafish as a potentially useful species in which to investigate compulsive-like behaviors.


Assuntos
Comportamento Animal/efeitos dos fármacos , Agonistas de Dopamina/farmacologia , Motivação/efeitos dos fármacos , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Recompensa , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Comportamento Social , Animais , Apomorfina/farmacologia , Citalopram/farmacologia , Conflito Psicológico , Modelos Animais de Doenças , Agonistas de Dopamina/administração & dosagem , Retroalimentação Psicológica , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Peixe-Zebra
2.
Int J Pers Cent Med ; 4(2): 69-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26140190

RESUMO

Global inequalities contribute to marked disparities in health and wellness of human populations. Many opportunities now exist to provide health care to all people in a person- and people-centered way that is effective, equitable, and sustainable. We review these opportunities and the scientific, historical, and philosophical considerations that form the basis for the International College of Person-centered Medicine's 2014 Geneva Declaration on Person- and People-centered Integrated Health Care for All. Using consistent time-series data, we critically examine examples of universal healthcare systems in Chile, Spain, and Cuba. In a person-centered approach to public health, people are recognized to have intrinsic dignity and are treated with respect to encourage their developing health and happiness. A person-centered approach supports the freedom and the responsibility to develop one's life in ways that are personally meaningful and that are respectful of others and the environment in which we live together. Evidence suggests that health care organizations function well when they operate in a person-and people-centered way because that stimulates better coordination, cooperation, and social trust. Health care coverage must be integrated at several interconnected levels in order to be effective, efficient, and fair. To reduce the burden of disease, integration is needed between the people seeking and delivering care, within the social network of each person, across the trajectory of each person's life, among primary caregivers and specialists, and across multiple sectors of society. For integration to succeed across all these levels, it must foster common values and a shared vision of the future.

4.
Comb Chem High Throughput Screen ; 12(8): 812-23, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19531008

RESUMO

Drug discovery efforts advance in step with advancements in assay technologies, as new technologies provide new lenses through which biology can be viewed. The novel information gathered results in the better understanding of drug-target interactions leading to better decision making during the drug discovery process. One area of rapid development is within label-free technologies. Label-free technologies offer many distinct advantages to the drug discovery workflow. One such novel technology is the CellKey System, an impedance-based label-free live cell assay platform. The system is based on impedance technology and is a universal platform for the functional measurement of all classes of G-protein coupled receptors (GPCRs). Data are generated in a kinetic fashion on both endogenously expressed and transfected receptors in a wide variety of cell types. In the studies detailed here, we used the system to perform an enhanced selectivity screen of a small panel of compounds simultaneously against two unrelated GPCR targets signaling through different pathways. Utilizing both the quantitative measures of cellular activation and the qualitative information inherent in the rich output data, we gained knowledge not only about the relative selectivity of each compound across both targets, but also about the character of the interaction of each with the cellular target. In this manner, we successfully demonstrated proof of principal for using an impedance-based technology to perform selectivity analyses and to triage lead compounds in a simplified format.


Assuntos
Bioensaio/métodos , Receptores Acoplados a Proteínas G/metabolismo , Animais , Bioensaio/instrumentação , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Descoberta de Drogas/instrumentação , Descoberta de Drogas/métodos , Cinética , Ligantes , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Sensibilidade e Especificidade , Coloração e Rotulagem
5.
Psychol Psychother ; 79(Pt 3): 461-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16945202

RESUMO

From 73 patients, 10 with the best, and 10 with the worst outcomes after psychotherapy were compared statistically for the frequency of 'not' and 'never' at commencement of psychotherapy, and for change in their frequency after therapy. A highly statistically significantly difference was found at commencement of psychotherapy in that the negative was used more frequently by the worst outcome group (p=.006). No significant differences were found for change in frequency after therapy. Thus, the frequent use of the negative at commencement of psychotherapy seems to predict a poor outcome.


Assuntos
Negação em Psicologia , Negativismo , Psicoterapia , Resultado do Tratamento , Humanos , Determinação da Personalidade , Prognóstico , Semântica , Falha de Tratamento , Comportamento Verbal
6.
Artigo em Inglês | AIM (África) | ID: biblio-1269788

RESUMO

Background: Following the introduction of a new; integrated; problem-oriented undergraduate medical curriculum at the University of Pretoria (UP) in 1997; a research project was undertaken to study interpersonal skills; professional attitudes; teamwork; ethics and related topics - which have come to be known collectively as `soft skills'. This contribution is the first of two articles on the professional socialisation of medical students and their development of `soft skills'. It describes the particular qualitative methodology developed for; and applied to; the study of soft skills among medical students at UP. Methods: This paper describes the aim of the study; reasons for adopting a qualitative research approach to achieve this aim; the theoretical orientation underpinning the qualitative approach that we considered most suitable; the design; the sampling; the data management and analysis; and the methods that we deployed to ensure the credibility of the findings. Research Design: The aim of the study was to explore the subjective meanings that students attributed to soft skills; as they understood them. These subjective meanings involve the way students interact meaningfully with fellow students; lecturers and other individuals participating in the medical and clinical education programme; and the way they construct shared conceptualisations of soft skills and medical education in their lives and social world. A qualitative approach was considered most appropriate; as this study set out to uncover subjective and diverse meanings that do not necessarily amount to generalisable truths. The particular qualitative strategy or design used was that of an extended case study; or `casing'; within the modernist theoretical orientation of symbolic interactionism. Elements of process evaluation were incorporated into the design to account for the process of curriculum reform within which this study was embedded.We recruited participants for this study from two cohorts of students. The first group; who completed their studies in 2001; had followed the traditional curriculum; while the second group; who completed their programme in 2002; had followed the reformed curriculum. The data collection tools were face-to-face individual interviews; focused group interviews and solicited autobiographical sketches. The utilisation of more than one method or data source enabled triangulation or cross-checking of findings. We followed an inductive reasoning approach; which means that we did not search for data to test any hypotheses that had been formulated prior to commencing the study; but focused instead on building constructs that were grounded in or reflected intimate familiarity with the students' world. Conclusion:The modernist qualitative research approach enabled us to uncover; describe and illuminate the subjective points of view on soft skills as expressed by final-year medical students before and after curriculum reform. More specifically; by carrying out an extended case study we were able to perform a process evaluation of the curriculum reform in terms of soft skills and the professional socialisation of the students. This paper outlines how qualitative research methods enabled us to capture and explore aspects of the inner life (social worlds) of these students. Whether they would be the same; similar or different in another setting are questions for further exploration or research - questions prompted by our study in a manner that illuminates the qualities that may be inherent in these subjective meanings


Assuntos
Medicina/educação , Estudantes
7.
Artigo em Inglês | AIM (África) | ID: biblio-1269789

RESUMO

Background: This paper reports on medical students' views on the ways in which their `soft skills' were developed. It is the result of a study on soft skills among two groups of students before and after curriculum reform at the School of Medicine of the University of Pretoria. One of the aims of the reform was to provide more teaching and learning opportunities for the development of soft skills. Soft skills include professional interpersonal and social skills; communication skills; and professional and ethical attitudes.Methods: As symbolic interactionism was used as the theoretical framework to guide the research; qualitative methods were used to collect the data. A purposive-theoretical sample of 42 final-year medical students from the traditional curriculum and 49 from the reformed curriculum was recruited. Data were collected by means of focus groups; individual in-depth interviews and autobiographical sketches.ResultsThe same categories of comments emerged from the data collected from the study participants from both the traditional and the reformed curriculum. The students ascribed their behaviour related to soft skills to personality and innate features. They had varying opinions on whether soft skills could be taught; but there was as a strong feeling that teaching should focus on principles and guidelines for dealing with difficult situations. They believed that; in the end; they should take responsibility for their own development of soft skills. Most participants felt they could at least grow through exposure to teaching activities and the observation of role models. They also indicated that they had developed their soft skills and constructed their own identity through their interaction with others. Their definition of situations was shaped by their interactions with doctors and educators; fellow students and other health professionals. Interaction with patients was considered the most important. For both groups of students their third year was a watershed; as it is the first year of more intensive patient contact and the beginning of serious learning from interaction with patients. The views on the development of soft skills differed very little between the traditional and reformed curriculum groups; except that students who had followed the reformed curriculum felt more prepared through the increased teaching and training efforts. Further consideration needs to be given to the intention of the changed curriculum compared to the actual effect.The way in which the participants in the study described their development of soft skills could be categorised as a complex interplay between `being' and `becoming'. Instead of using the word `acquisition' of soft skills; `development' seemed to be more appropriate. The metaphor of `guiding' and `growing' also captures the development of these skills better than the terms `teaching' and `learning'. Conclusion: Teaching activities in the clinical years should be adapted with a view to facilitating the students' professional growth. New models for the development of medical educators should be created and institutional barriers should be investigated


Assuntos
Medicina/educação , África do Sul , Estudantes de Medicina
8.
Aust N Z J Psychiatry ; 38(4): 226-32, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15038801

RESUMO

OBJECTIVE: To examine changes in linguistic markers in the course of psychotherapy, drawing on Frege's logic of relations to define semantic variables distinct from syntactic variables. METHOD: From a sample of 73 patients, 10 patients with the best and 10 patients with the worst outcomes were selected. Forty transcribed sessions of each outcome group were compared statistically for change between commencement and termination of psychotherapy in: (i) the syntactic usage of first person pronouns ('I', 'me', 'we', 'us', 'implied I', 'implied me'); (ii) semantic usage of first person pronouns (expressing alpha, omega, or unclear positions); and (iii) non-pronoun linguistic variables (passive voice, negative, copula, auxiliary verbs expressing a sense of obligation). RESULTS: There were no significant differences between the best and worst outcome groups in the change of either syntactic usage, or of the non-pronoun linguistic variables. However, the outcome groups differed significantly in the change of their semantic usage (alpha: p = 0.002; omega: p = 0.028): The best outcome group showed an increase of alpha positions and a decrease of omega positions, whereas the worst outcome group showed the inverse (i.e. decrease of alpha and increase of omega positions). CONCLUSIONS: Results suggest only semantic, that is meaning-driven, usage of first person pronouns marks recovery in the course of psychotherapy. If replicated, this finding could be used to monitor treatment responses. Replication in other kinds of treatment could mean these semantic changes are markers of recovery more generally than in psychotherapy.


Assuntos
Idioma , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Psicoterapia/métodos , Psicoterapia/estatística & dados numéricos , Recuperação de Função Fisiológica , Semântica , Humanos , Linguística/métodos , Linguística/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Gravação em Fita
9.
J Med Ethics ; 29(1): 41-3, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12569195

RESUMO

What renders some mentally disordered patients incapable of informed consent to medical interventions? It is argued that a patient is incapable of giving informed consent owing to mental disorder, if a mental disorder prevents a patient from understanding what s/he consents to; if a mental disorder prevents a patient from choosing decisively; if a mental disorder prevents a patient from communicating his/her consent; or if a mental disorder prevents a patient from accepting the need for a medical intervention. This paper holds that a patient's capacity to give informed consent should be assessed clinically by using these conditions necessary for informed consent, and should be assessed specifically for each intervention and specifically at the time when the consent has to be given. The paper considers patients' incapacity to give informed consent to treatment, to give informed consent to be examined clinically, and to give informed consent to participate in research.


Assuntos
Consentimento Livre e Esclarecido/ética , Competência Mental/psicologia , Transtornos Mentais/psicologia , Comportamento de Escolha/ética , Cognição , Comunicação , Humanos , Consentimento Livre e Esclarecido/legislação & jurisprudência , Autoimagem , Reino Unido
10.
Am J Vet Res ; 62(11): 1755-60, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11703020

RESUMO

OBJECTIVE: To determine potency and selectivity of nonsteroidal anti-inflammatory drugs (NSAID) and cyclooxygenase- (COX-) specific inhibitors in whole blood from horses, dogs, and cats. SAMPLE POPULATION: Blood samples from 30 healthy horses, 48 healthy dogs, and 9 healthy cats. PROCEDURE: Activities of COX-1 and COX-2 were determined by measuring coagulation-induced thromboxane and lipopolysaccharide-induced prostaglandin E2 concentrations, respectively, in whole blood with and without the addition of various concentrations of phenylbutazone, flunixin meglumine, ketoprofen, diclofenac, indomethacin, meloxicam, carprofen, 5-bromo-2[4-fluorophenyl]-3-14-methylsulfonylphenyl]-thiophene (DuP 697), 5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl) phenyl-2(5H)-furan one (DFU), 3-(3,4-difluorophenyl)-4-(4-(methylsulfonyl)phenyl)-2-(5H)-furanone (MF-tricyclic), and celecoxib. Potency of each test compound was determined by calculating the concentration that resulted in inhibition of 50% of COX activity (IC50). Selectivity was determined by calculating the ratio of IC50 for COX-1 to IC50 for COX-2 (COX-1/COX-2 ratio). RESULTS: The novel compound DFU was the most selective COX-2 inhibitor in equine, canine, and feline blood; COX-1/COX-2 ratios were 775, 74, and 69, respectively. Carprofen was the weakest inhibitor of COX-2, compared with the other COX-2 selective inhibitors, and did not inhibit COX-2 activity in equine blood. In contrast, NSAID such as phenylbutazone and flunixin meglumine were more potent inhibitors of COX-1 than COX-2 in canine and equine blood. CONCLUSIONS AND CLINICAL RELEVANCE: The novel COX-2 inhibitor DFU was more potent and selective in canine, equine, and feline blood, compared with phenylbutazone, flunixin meglumine, and carprofen. Compounds that specifically inhibit COX-2 may result in a lower incidence of adverse effects, compared with NSAID, when administered at therapeutic dosages to horses, dogs, and cats.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Gatos/sangue , Inibidores de Ciclo-Oxigenase/farmacologia , Cães/sangue , Cavalos/sangue , Animais , Carbazóis/farmacologia , Clonixina/análogos & derivados , Clonixina/farmacologia , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Dinoprostona/biossíntese , Dinoprostona/sangue , Feminino , Furanos/farmacologia , Concentração Inibidora 50 , Isoenzimas/antagonistas & inibidores , Isoenzimas/sangue , Masculino , Fenilbutazona/farmacologia , Prostaglandina-Endoperóxido Sintases/sangue , Tromboxano B2/biossíntese , Tromboxano B2/sangue
11.
Br J Pharmacol ; 126(4): 979-88, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10193778

RESUMO

1. The aim of this study was to assess the inhibitory activities of phosphodiesterase type 4 (PDE4) inhibitors on tumour necrosis factor-alpha (TNF-alpha) and leukotriene B4 (LTB4) production in a novel human whole blood assay. 2. Lipopolysaccharide (LPS) stimulation of human whole blood caused a time dependent increase in TNF-alpha and prostaglandin E2 (PGE2) plasma levels. Inhibition of LPS-induced TNF-alpha by the selective PDE4 inhibitor RP73401 was proportionally enhanced with endogenous PGE2 (maximal after 24 h). In contrast, blocking endogenous PGE2 production with indomethacin in blood stimulated with LPS for 24 h decreased the potency of RP73401 to that observed with a 4 h LPS incubation. 3. Non-selective and selective PDE4 inhibitors showed greater inhibition of LPS-induced TNF-alpha after 24 h compared to 4 h. Stereoselectivity was only achieved in the 24 h method. 4. LPS-stimulation of whole blood for either 30 min or 24 h followed by N-formyl-Met-Leu-Phe (fMLP) activation resulted in low plasma LTB4 levels. Combination of both treatments resulted in a greater than 7 fold increase in plasma LTB4 levels. Inhibition of the double LPS and fMLP-activated LTB4 production was observed with non-selective and PDE4-selective inhibitors. Their LTB4 inhibitory potencies were similar to that observed in the 24 h LPS-induced TNF-alpha assay. Thus, stimulation of human whole blood with two LPS stimulations followed by fMLP gives rise to both TNF-alpha and LTB4 and their inhibition by various compounds can be assessed in the same blood sample. 5. Calcium ionophore (A23187) stimulation of whole blood resulted in plasma LTB4 levels similar to the double LPS and fMLP method. Inhibition of A23187-induced LTB4 biosynthesis was also achieved by PDE4-selective inhibitors as well as the direct 5-lipoxygenase (5-LO) inhibitor L-739,010. 6. These results confirm the anti-inflammatory properties of PDE4 inhibitors. Thus, this novel human whole blood can be used to assess the biochemical efficacy of PDE4 inhibitors in human subjects.


Assuntos
Leucotrieno B4/biossíntese , Inibidores de Fosfodiesterase/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Calcimicina/farmacologia , Dinoprostona/biossíntese , Feminino , Humanos , Leucotrieno B4/sangue , Lipopolissacarídeos/farmacologia , Masculino , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Piridinas/farmacologia
12.
Am J Respir Cell Mol Biol ; 13(2): 133-43, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7626283

RESUMO

The ovalbumin-sensitized guinea pig is commonly used as a small animal model of allergic asthma. This animal model exhibits many of the hallmark characteristics observed in patients afflicted with asthma including nonspecific airway hyperreactivity, airway eosinophilia, early and late phase bronchoconstriction, and plasma extravasation into the airways. In addition, mucous hypersecretion in the airways of asthmatic patients is thought to be responsible for the plugging of distal airways and to contribute to the morbidity and mortality associated with the disease process. In this study we examined whether the allergic guinea pig model exhibits an increase in airway high molecular weight glycoconjugate (HMWG) secretion in response to an antigen challenge and whether dexamethasone exerts any modulatory effects upon the response. Ovalbumin (OVA) -sensitized guinea pigs were challenged with OVA 2 wk following the initial exposure. Trachobronchoalveolar lavages (TBAL) were performed, and the samples were assayed for total eosinophil cell number, eosinophil peroxidase activity (EPO), and both acidic and neutral HMWG content. Morphometric analysis of mucous-containing cells was also performed on tissue sections prepared from the trachea, mainstem bronchus, and three lobes of the left lung. Within 24 h of an antigen challenge, TBAL samples obtained from the allergic guinea pigs exhibited increases in eosinophil cell number, measured EPO enzyme activity, and acidic HMWG content compared to TBAL samples prepared from vehicle-exposed animals. These antigen-induced changes were dependent on the concentration of aerosolized OVA administered. Exposing the animals to 0.3% OVA provoked a 6.23-fold increase in airway eosinophils, 15-fold elevation in TBAL EPO enzyme activity, and 175% increase in TBAL acidic HMWG. No significant changes in TBAL neutral HMWG were measured. The changes in measured EPO activity correlated with the levels of acidic HMWG found in the TBAL samples (r = 0.73, P < or = 0.001). The measured increase in TBAL acidic HMWG was time dependent and was found to be maximal at 2 h post-antigen challenge. Morphometric analysis of Alcian blue (pH 2.5) -stained airway sections showed a decline in stored mucosubstances following the antigen exposure, supporting the notion that the allergic guinea pig model exhibits a mucosecretory component. Pretreating the animals with dexamethasone attenuated the antigen-induced release of HMWG and changes in measured EPO activity. In conclusion, these data indicate that the allergic guinea pig may be a useful model for examining the neural and cellular mechanisms underlying mucus hypersecretion in individuals afflicted with bronchial asthma.


Assuntos
Dexametasona/farmacologia , Glicoconjugados/metabolismo , Hipersensibilidade/tratamento farmacológico , Ovalbumina/metabolismo , Animais , Asma/imunologia , Líquido da Lavagem Broncoalveolar/química , Modelos Animais de Doenças , Eosinófilos/efeitos dos fármacos , Eosinófilos/metabolismo , Glicoconjugados/análise , Cobaias , Masculino , Peso Molecular , Muco/metabolismo , Ovalbumina/imunologia
13.
Am J Respir Crit Care Med ; 151(6): 1931-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7767542

RESUMO

Chronic exposure of rats to high concentrations of SO2 gas causes pathologic changes in airway similar to those seen in human chronic bronchitis. The purpose of this study was to examine the pulmonary mechanical correlates of these changes and to quantify the extent of mucous hypersecretion by measuring changes in mucous glycoproteins. Female Sprague-Dawley rats were exposed to 250 ppm SO2 gas, 5 h/d, 5 d/wk, for a period of 4 wk. Control rats were exposed to air only. On the day after the last SO2 exposure, rats were anesthetized, instrumented for the measurement of pulmonary resistance (RL) and dynamic compliance (Cdyn), and ventilated. Chronic SO2 exposure caused a small but significant increase in RL and decrease in Cdyn. Airway responsiveness to inhaled aerosolized methacholine was increased in SO2-exposed rats, as indicated by approximately 6.6- and 4.6-fold decreases respectively, in the doses of inhaled methacholine required to double RL or decrease Cdyn to 50% of baseline. SO2 exposure had no effect on the contractile response of the trachea measured in vitro. Tracheae and lungs from SO2-exposed animals exhibited 140 and 535% increases in measured neutral mucous glycoproteins, respectively, and 33 and 37% increases in acid glycoproteins. Our results indicate that this animal model of chronic bronchitis mimics the mucous hypersecretion, airway obstruction, and increased airway responsiveness observed in human bronchitis and may allow us to begin to probe their mechanistic basis.


Assuntos
Hiper-Reatividade Brônquica/fisiopatologia , Bronquite/fisiopatologia , Animais , Brônquios/metabolismo , Brônquios/fisiopatologia , Testes de Provocação Brônquica , Bronquite/induzido quimicamente , Bronquite/diagnóstico , Feminino , Glicoproteínas/metabolismo , Pulmão/fisiopatologia , Cloreto de Metacolina , Mucinas/metabolismo , Muco/química , Muco/metabolismo , Ratos , Ratos Sprague-Dawley , Dióxido de Enxofre , Traqueia/fisiopatologia
14.
Can J Physiol Pharmacol ; 72(9): 1025-30, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7842384

RESUMO

The ability of aerosolized sodium metabisulfite to induce hypertrophic and hyperplastic changes in rat airway secretory epithelial cells was investigated. A 10% solution of sodium metabisulfite was aerosolized into a Plexiglas exposure chamber, using an ultrasonic humidifier. The level of SO2 gas generated by this apparatus was measured to be 500 ppm. Measured levels of neutral and acidic mucous glycoproteins in extracts from tracheal and lung tissue were used as indices of hypertrophic (increases in mucus content per cell) and hyperplastic (increased numbers of cells containing mucus per gram of tissue) changes occurring in mucus-secreting cells of the airways. Exposing rats to sodium metabisulfite for 3 weeks resulted in profound increases in total neutral mucous glycoproteins found in tracheal and lung tissue (6.2-fold and 10.1-fold, respectively), compared with the H2O-treated counterparts. Total acidic mucous glycoproteins were significantly elevated in lung tissue only (13.5-fold). In addition, neutral and acidic mucous glycoproteins were elevated 20-fold and 9-fold, respectively, in bronchoalveolar lavage samples prepared from sodium metabisulfite exposed animals. These results indicate that aerosolized sodium metabisulfite may be a useful agent for developing small animal models of mucus hypersecretion.


Assuntos
Epitélio/efeitos dos fármacos , Glicoproteínas/análise , Muco/metabolismo , Sulfitos/administração & dosagem , Aerossóis , Animais , Modelos Animais de Doenças , Epitélio/metabolismo , Epitélio/patologia , Hiperplasia/induzido quimicamente , Hipertrofia/induzido quimicamente , Pulmão , Pneumopatias Obstrutivas/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Projetos de Pesquisa , Traqueia
15.
Am J Respir Cell Mol Biol ; 10(6): 625-34, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7516172

RESUMO

Determination of hyperplastic and hypertrophic changes of mucus-secreting cells in animal airways has been performed in the past by using histologic, immunologic, and/or molecular biologic approaches. Histologic techniques are tedious and time-consuming. The other approaches require specific antibodies and cDNA probes that have proved difficult to develop. Described here is a method for the rapid estimation of hyperplastic and hypertrophic changes of secretory epithelial cells in rat airways. The assay specifically measures acidic and neutral mucoproteins in a linear fashion from 0.5 microgram to at least 10 micrograms. Male Sprague-Dawley rats were exposed to metabisulfite mist (10% wt/vol) for 5 days/wk for 3 wk. The lungs were removed and homogenized in a phosphate-buffered solution containing reducing agents and protease inhibitors. The particulate matter was removed by centrifugation, and the soluble extract was applied to a column packed with Sepharose CL-6B. The material eluting in the void volume was applied to a PVDF membrane and stained for either acidic or neutral mucosubstances using Alcian blue or periodic acid-Schiff (PAS) staining, and the absorbance was read using a 96-well plate reader. Lungs from sodium metabisulfite-exposed animals showed a 7-fold and 3.5-fold increase in PAS-positive and Alcian blue-positive material, respectively. The increase in both PAS and Alcian blue staining was hyaluronidase and chondroitinase insensitive. The observed changes are consistent with morphometric measurements of mucus-containing cells in histologic sections of the tissues. This assay may be useful in determining which neurohumoral mediators might be involved in mucus cell hypertrophy and hyperplasia in animal models of chronic obstructive pulmonary disease.


Assuntos
Azul Alciano , Histocitoquímica/métodos , Pulmão/patologia , Mucinas/análise , Reação do Ácido Periódico de Schiff , Administração por Inalação , Animais , Cromatografia em Agarose , Epitélio/patologia , Hiperplasia , Hipertrofia , Pulmão/química , Masculino , Mucinas/efeitos dos fármacos , Mucinas/isolamento & purificação , Proteoglicanas/análise , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Sulfitos/administração & dosagem , Sulfitos/farmacologia , Traqueia/química
16.
Pflugers Arch ; 421(4): 400-2, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1408665

RESUMO

We have developed a system for immobilizing non-adherent cells for use in macroscopic fluorescence measurements in a perfused cuvette. Using normal human T lymphocytes loaded with the fluorescent Ca(2+)-indicator, fluo-3, we have validated the properties of these cells immobilized on clear, non-fluorescent fluorohalocarbon film (Aclar) using the non-charged cell adhesive, Cell-Tak.


Assuntos
Separação Celular/métodos , Perfusão/métodos , Humanos , Espectrometria de Fluorescência/métodos , Linfócitos T
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