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1.
Ment Health Phys Act ; 19: 100360, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33020704

RESUMO

The aim of this review is to systematically describe and quantify the effects of PA interventions on alcohol and other drug use outcomes, and to identify any apparent effect of PA dose and type, possible mechanisms of effect, and any other aspect of intervention delivery (e.g. key behaviour change processes), within a framework to inform the design and evaluation of future interventions. Systematic searches were designed to identify published and grey literature on the role of PA for reducing the risk of progression to alcohol and other drug use (PREVENTION), supporting individuals to reduce alcohol and other drug use for harm reduction (REDUCTION), and promote abstinence and relapse prevention during and after treatment of alcohol and other drug use (TREATMENT). Searches identified 49,518 records, with 49,342 excluded on title and abstract. We screened 176 full text articles from which we included 32 studies in 32 papers with quantitative results of relevance to this review. Meta-analysis of two studies showed a significant effect of PA on prevention of alcohol initiation (risk ratio [RR]: 0.72, 95%CI: 0.61 to 0.85). Meta-analysis of four studies showed no clear evidence for an effect of PA on alcohol consumption (Standardised Mean Difference [SMD]: 0.19, 95%, Confidence Interval -0.57 to 0.18). We were unable to quantitatively examine the effects of PA interventions on other drug use alone, or in combination with alcohol use, for prevention, reduction or treatment. Among the 19 treatment studies with an alcohol and other drug use outcome, there was a trend for promising short-term effect but with limited information about intervention fidelity and exercise dose, there was a moderate to high risk of bias. We identified no studies reporting the cost-effectiveness of interventions. More rigorous and well-designed research is needed. Our novel approach to the review provides a clearer guide to achieve this in future research questions addressed to inform policy and practice for different populations and settings.

2.
J Microsc ; 259(2): 137-142, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25907464

RESUMO

Serial block-face scanning electron microscopy (SBEM) is becoming increasingly popular for a wide range of applications in many disciplines from biology to material sciences. This review focuses on applications for circuit reconstruction in neuroscience, which is one of the major driving forces advancing SBEM. Neuronal circuit reconstruction poses exceptional challenges to volume EM in terms of resolution, field of view, acquisition time and sample preparation. Mapping the connections between neurons in the brain is crucial for understanding information flow and information processing in the brain. However, information on the connectivity between hundreds or even thousands of neurons densely packed in neuronal microcircuits is still largely missing. Volume EM techniques such as serial section TEM, automated tape-collecting ultramicrotome, focused ion-beam scanning electron microscopy and SBEM (microtome serial block-face scanning electron microscopy) are the techniques that provide sufficient resolution to resolve ultrastructural details such as synapses and provides sufficient field of view for dense reconstruction of neuronal circuits. While volume EM techniques are advancing, they are generating large data sets on the terabyte scale that require new image processing workflows and analysis tools. In this review, we present the recent advances in SBEM for circuit reconstruction in neuroscience and an overview of existing image processing and analysis pipelines.


Assuntos
Microscopia Eletrônica de Varredura/métodos , Microtomia , Vias Neurais/ultraestrutura , Neurociências/métodos , Animais , Encéfalo/ultraestrutura , Conectoma , Técnicas de Preparação Histocitológica , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura/instrumentação , Neurônios/ultraestrutura , Sinapses/ultraestrutura
3.
Rev Sci Instrum ; 83(11): 115101, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23206092

RESUMO

An in situ stress analysis by means of synchrotron x-ray diffraction was carried out during laser surface hardening of steel. A single exposure set-up that based on a special arrangement of two fast silicon strip line detectors was established, allowing for fast stress analysis according to the sin(2)ψ x-ray analysis method. For the in situ experiments a process chamber was designed and manufactured, which is described in detail. First measurements were carried out at the HZG undulator imaging beamline (IBL, beamline P05) at the synchrotron storage ring PETRA III, DESY, Hamburg (Germany). The laser processing was carried out using a 6 kW high power diode laser system. Two different laser optics were compared, a Gaussian optic with a focus spot of ø 3 mm and a homogenizing optic with a rectangular spot dimension of 8 × 8 mm(2). The laser processing was carried out using spot hardening at a heating-/cooling rate of 1000 K/s and was controlled via pyrometric temperature measurement using a control temperature of 1150 °C. The set-up being established during the measuring campaign allowed for this first realization data collection rates of 10Hz. The data evaluation procedure applied enables the separation of thermal from elastic strains and gains unprecedented insight into the laser hardening process.

4.
Int J Hyg Environ Health ; 210(3-4): 345-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17321208

RESUMO

The Integrated Exposure Assessment Survey (INES) was started in the year 2005. Altogether 50 healthy adults living in Bavaria, Germany, were included into the study. Monitoring was conducted in accordance with relevant routes of human exposure (inhalation, ingestion) and integrated different pathways (indoor air, food, house dust). This approach consisted of a combination of external measurements of contaminants with the determination of these substances or their metabolites in body fluids. The target substances were phthalates, perfluorinated compounds (PFC), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), and polybrominated diphenylethers (PBDEs). This paper gives a brief description of the objectives and the concept of INES as well as methods of sampling and analyses of target compounds. Some preliminary results of biomonitoring data for PFC and phthalates as well as of the dietary intake of DEHP will be discussed.


Assuntos
Poluentes Atmosféricos/metabolismo , Exposição Ambiental/análise , Monitoramento Ambiental , Adolescente , Adulto , Poluentes Atmosféricos/análise , Benzofuranos/sangue , Benzofuranos/urina , Estudos de Coortes , Dibenzofuranos Policlorados , Registros de Dieta , Poeira/análise , Feminino , Contaminação de Alimentos/análise , Alemanha , Éteres Difenil Halogenados , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Éteres Fenílicos/sangue , Éteres Fenílicos/urina , Ácidos Ftálicos/sangue , Ácidos Ftálicos/urina , Bifenilos Policlorados/sangue , Bifenilos Policlorados/urina , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/sangue , Dibenzodioxinas Policloradas/urina
5.
Eur Respir J ; 27(1): 172-87, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16387951

RESUMO

Inhaled corticosteroids suppress airway inflammation and components of airway remodelling in bronchial asthma. In the tracheobronchial (airway) vasculature, these include the inhibition of inflammatory hyperperfusion, microvascular hyperpermeability, mucosal oedema formation, and the formation of new blood vessels (angiogenesis). Corticosteroids are now known to exert their effects on the airway vasculature through genomic and nongenomic mechanisms. Genomic actions involve the regulation of target genes, and suppress most of the vascular elements of inflammation and angiogenesis in the airway. In contrast, nongenomic actions are mediated by rapid cellular mechanisms, and induce transient vasoconstriction in the airway, thereby reversing inflammatory hyperperfusion. The vascular actions of corticosteroids contribute to controlling clinical symptoms of asthma primarily by influencing airway calibre in the lung periphery and airway hyperreactivity. In this review article, recent advances into the understanding of cellular mechanisms and the clinical implications of the interaction of inhaled corticosteroids and the airway vasculature in asthma are reviewed.


Assuntos
Corticosteroides/administração & dosagem , Asma/tratamento farmacológico , Brônquios/irrigação sanguínea , Administração por Inalação , Corticosteroides/genética , Obstrução das Vias Respiratórias/fisiopatologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Resistência das Vias Respiratórias/genética , Asma/genética , Asma/fisiopatologia , Velocidade do Fluxo Sanguíneo , Brônquios/efeitos dos fármacos , Broncoconstrição/efeitos dos fármacos , Genoma , Humanos , Músculo Liso Vascular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
6.
Eur J Hum Genet ; 12(5): 365-71, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14735163

RESUMO

Familial adenomatous polyposis (FAP), an autosomal dominantly inherited colorectal cancer predisposition syndrome, displays considerable inter- and intrafamilial phenotypic heterogeneity, which represents a major problem in genetic counselling of APC mutation carriers. The Min mouse model indicated a putative disease modifier locus on chromosome 4, which is syntenic to human chromosome 1p35-36. This finding was subsequently supported by parametric and nonparametric linkage analyses in FAP families, however, without identifying functional variants in candidate genes. Recently, germline mutations in the base-excision repair gene MYH (1p33-34) have been described in patients with multiple adenomas, pointing to a possible role as disease modifier in FAP. Here, we present critical reassessment of one of the largest FAP kindreds published, which was previously used in linkage mapping of 1p35-36. In this family, all affected members harbour the same APC germline mutation (5945delA), but display marked phenotypic variability, in particular regarding the occurrence of extracolonic disease that segregates in several branches of the family tree. Using updated clinical information, additional mutation carriers and polymorphic markers, fine mapping of the critical region as well as mutation analysis of the MYH gene were performed. These investigations allowed us to significantly exclude (i) the 1p33-36 region as a modifier locus and (ii) MYH as a modifier gene for extracolonic disease in this FAP kindred. Our results do not eliminate 1p33-36 from suspicion in other families, but clearly indicate that in our family linkage analysis of further putative candidate regions is necessary to identify a disease modifier locus in FAP.


Assuntos
Polipose Adenomatosa do Colo/genética , Cromossomos Humanos Par 1/genética , Polipose Adenomatosa do Colo/patologia , Adulto , Fatores Etários , Idoso , Mapeamento Cromossômico , DNA Glicosilases/genética , Saúde da Família , Feminino , Ligação Genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Escore Lod , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Modelos Genéticos , Mutação , Linhagem , Penetrância , Fenótipo , Suíça
7.
Lung ; 181(4): 201-11, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14692560

RESUMO

Although the relative effect of racemic and (R)-albuterol on airway smooth muscle tone have been investigated in patients with airflow obstruction, the comparative effectiveness of these drugs in relaxing airway vascular smooth muscle is unknown. Therefore, we determined the actions of inhaled racemic and (R)-albuterol on airway mucosal blood flow (Qaw) normalized for anatomic dead space as an index of airway vascular smooth muscle tone in 11 healthy subjects and 10 subjects with mild asthma. We also monitored the forced expiratory volume in 1 second (FEV1) as an index of airway smooth muscle tone. Mean +/- SE baseline Qaw was 43.1 +/- 1.5 microl x min(-1) x ml(-1) in healthy subjects and 53.4 +/- 2.1 microl x min(-1) x ml(-1) in asthmatic subjects (p < 0.01). The corresponding values for FEV1 were 95.6 +/- 1.4 and 86.8 +/- 2.5% respectively, of predicted (p = 0.01). Racemic and (R)-albuterol caused a transient, dose-dependent increase of Qaw in healthy, but not in asthmatic subjects; the responses were not different between the two drugs. The FEV1 tended to increase more in asthmatics than in healthy subjects, again without a difference between the two drugs. These results show that racemic and (R)-albuterol have comparable effects on airway vascular smooth muscle and suggest that the blunted airway vascular smooth muscle response to albuterol in asthmatics is not related to (S)-albuterol.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Asma/fisiopatologia , Brônquios/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Administração por Inalação , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/química , Adulto , Albuterol/administração & dosagem , Albuterol/química , Brônquios/irrigação sanguínea , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Fatores de Tempo , Vasodilatação/efeitos dos fármacos
8.
Eur Respir J ; 21(6): 989-93, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12797493

RESUMO

The vasoconstrictive efficacies of glucocorticosteroids (GS) are usually compared by the McKenzie skin-blanching test and taken as an index of relative potency. The rationale for the present study was to transpose the McKenzie test to the airway and to compare the airway vascular effects of three inhaled GS: beclomethasone dipropionate (BDP), fluticasone propionate (FP) and budesonide (BUD), in healthy subjects and patients with mild stable asthma. A soluble, inert gas-uptake method was used to measure airway blood flow (Qaw). Baseline mean+/-SD Qaw normalised for anatomical dead space was 53.1+/-1.4 microL x min(-1) x mL(-1) in healthy subjects (n=10) and 67.8+/-3 microL x min(-1) x mL(-1) in asthmatics (n=10). All GS caused a transient decrease in Qaw. The magnitude of the vasoconstriction was greater in asthmatics. The relative vasoconstrictive effect of BDP, FP and BUD was 1, 1.9, and 2.7, respectively, in asthmatics and 1, 3.3 and 3.0, respectively, in healthy subjects, as assessed by the dose required to decrease Qaw by 20%, from the baseline, 30-min postdrug inhalation. Therefore, measuring airway blood flow may be a useful, site-specific parameter to assess the tissue bioavailability and vasoconstrictive efficacy of inhaled glucocorticosteroids.


Assuntos
Androstadienos/administração & dosagem , Androstadienos/uso terapêutico , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Beclometasona/administração & dosagem , Beclometasona/uso terapêutico , Brônquios/irrigação sanguínea , Brônquios/efeitos dos fármacos , Budesonida/administração & dosagem , Budesonida/uso terapêutico , Vasoconstrição/efeitos dos fármacos , Administração por Inalação , Adolescente , Adulto , Androstadienos/farmacologia , Anti-Inflamatórios/farmacologia , Asma/fisiopatologia , Beclometasona/farmacologia , Brônquios/fisiopatologia , Budesonida/farmacologia , Relação Dose-Resposta a Droga , Feminino , Fluticasona , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Índice de Gravidade de Doença , Vasoconstrição/fisiologia
10.
Arch Physiol Biochem ; 111(4): 327-9, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15764066

RESUMO

Several studies have demonstrated that nasal challenges can induce reflex responses in the respiratory system. Some authors have described bronchoconstriction and modification of the pattern of breathing following nasal challenges by irritants and cold air. We propose to determine the effect of nasal stimulation with cold dry air on airway mucosal blood flow (Qaw) in the proximal tracheal bronchial tree of healthy humans. Nine healthy subjects participated in the study. Baseline measurement Qaw, nasal airway resistance (NAR) and airway caliber by specific airways conductance (SGaw) were followed by nasal challenge with cold dry air. Qaw, NAR and Sgaw were determined after the challenge. In those subjects in which a significant decline in Qaw was recorded the protocol was repeated after pretreatment with nasal anesthesia using topical lidocaine. Cold dry air challenge produced a significant decrease in mean Qaw for the nine subjects and this response was abolished by pretreatment with nasal anesthesia using topical lidocaine. There was no significant change in Sgaw and NAR after the challenge and topical lidocaine anesthesia. Our data indicates that nasal stimulation with cold dry air leads to a reduction in Qaw and that this effect may be mediated by a nasal reflex.


Assuntos
Ar , Mucosa Nasal/irrigação sanguínea , Adulto , Anestésicos Locais/farmacologia , Temperatura Baixa , Feminino , Humanos , Lidocaína/farmacologia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia
11.
Arch Physiol Biochem ; 111(4): 341-4, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15764070

RESUMO

The actions of norepinephrine (NE) released from airway sympathetic nerves are partially terminated by the extraneuronal catecholamine uptake. Because various steroid hormones inhibit extraneuronal uptake, it could be responsible for the airway vasoconstriction caused by inhaled glucocorticosteroids (GSs) in vivo. Using bronchial arteries obtained from donor lungs rejected for transplantation, we showed that a plasma membrane-associated transporter is responsible for NE uptake by airway vascular smooth muscle. We identified this transporter, namely the extraneuronal monoamine transporter (EMT), by demonstrating its function and mRNA expression. Furthermore, we showed that the rapid, nongenomic inhibitory GS effect on EMT is likely mediated through the activation of specific K+ channels in the plasma membrane. We believe that our studies identified new molecular targets for GSs in modulating noradrenergic control of airway vascular tone.


Assuntos
Brônquios/irrigação sanguínea , Artérias Brônquicas/metabolismo , Músculo Liso Vascular/metabolismo , Esteroides/metabolismo , Sítios de Ligação , Membrana Celular/metabolismo , Corticosterona/metabolismo , Humanos , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Potássio/metabolismo , Canais de Potássio/metabolismo , RNA Mensageiro/metabolismo , Simportadores/biossíntese , Simportadores/genética
12.
Eur Respir J ; 19(2): 217-24, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11866001

RESUMO

Currently available inhaled bronchodilators used as therapy for chronic obstructive pulmonary disease (COPD) necessitate multiple daily dosing. The present study evaluates the long-term safety and efficacy of tiotropium, a new once-daily anticholinergic in COPD. Patients with stable COPD (age 65.2+/-8.7 yrs (mean+/-SD), n=921) were enrolled in two identical randomized double-blind placebo-controlled 1-yr studies. Patients inhaled tiotropium 18 microg or placebo (mean screening forced expiratory volume in one second (FEV1) 1.01 versus 0.99 L, 39.1 and 38.1% of the predicted value) once daily as a dry powder. The primary spirometric outcome was trough FEV1 (i.e. FEV1 prior to dosing). Changes in dyspnoea were measured using the Transition Dyspnea Index, and health status with the disease-specific St. George's Respiratory Questionnaire and the generic Short Form 36. Medication use and adverse events were recorded. Tiotropium provided significantly superior bronchodilation relative to placebo for trough FEV1 response (approximately 12% over baseline) (p<0.01) and mean response during the 3 h following dosing (approximately 22% over baseline) (p<0.001) over the 12-month period. Tiotropium recipients showed less dyspnoea (p<0.001), superior health status scores, and fewer COPD exacerbations and hospitalizations (p<0.05). Adverse events were comparable with placebo, except for dry mouth incidence (tiotropium 16.0% versus placebo 2.7%, p<0.05). Tiotropium is an effective, once-daily bronchodilator that reduces dyspnoea and chronic obstructive pulmonary disease exacerbation frequency and improves health status. This suggests that tiotropium will make an important contribution to chronic obstructive pulmonary disease therapy.


Assuntos
Broncodilatadores/administração & dosagem , Antagonistas Colinérgicos/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/administração & dosagem , Administração por Inalação , Idoso , Broncodilatadores/efeitos adversos , Antagonistas Colinérgicos/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Feminino , Nível de Saúde , Humanos , Masculino , Pico do Fluxo Expiratório , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Derivados da Escopolamina/efeitos adversos , Espirometria , Brometo de Tiotrópio
13.
J Aerosol Med ; 14(3): 369-75, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11693849

RESUMO

The purpose of the study was to assess the effect of unilateral bronchoconstriction on the deposition patterns of aerosolized particles in a sheep model. Unilateral bronchoconstriction was induced in intubated conscious sheep by placing a protective, obstructing balloon catheter in either main bronchus, prior to administration of aerosolized carbachol at a dose that increased pulmonary resistance by 200-400% above baseline. The catheter was then removed and the animals were positioned under a gamma camera. An equilibrium image was obtained with xenon (133Xe), to determine a lung outline that was used to calculate the proportion of counts in each lung. Aerosols, labeled with technetium (99mTc) and generated by two jet nebulizers, were inhaled tidally by the sheep in serial experiments. (For nebulizer A, mass median aerodynamic diameter [MMAD] = 0.39 microm; for nebulizer B, MMAD = 1.1 microm.) For nebulizer A, percentage deposition in the treated and untreated lungs was not significantly different (50.8% versus 49.2%, respectively), while for nebulizer B, the median deposition in the carbachol treated lung was significantly greater than in the untreated lung (55.8% versus 44.2% respectively; p = 0.005). There was a more central pattern of deposition in the treated lung than in the untreated lung for both nebulizers, but the degree of central deposition was significantly greater with nebulizer B. The findings of the present study suggest that regional obstruction does not preclude the delivery of therapeutic aerosols to the airways in such a region, and may, depending on the size of the aerosol, result in enhanced airway deposition relative to less obstructed regions.


Assuntos
Broncoconstrição , Carbacol/administração & dosagem , Sistemas de Liberação de Medicamentos , Aerossóis , Animais , Feminino , Nebulizadores e Vaporizadores , Ovinos
14.
Am J Respir Cell Mol Biol ; 25(4): 500-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11694456

RESUMO

We have shown that an inhaled glucocorticosteroid (GS) causes alpha(1)-adrenergic antagonist-blockable, rapid, and transient bronchial vasoconstriction in healthy and asthmatic subjects. Steroids inhibit norepinephrine (NE) uptake by non-neuronal cells, thereby increasing NE concentration at alpha-adrenergic receptor sites. This could explain the GS-induced bronchial vasoconstriction. We therefore studied expression of the steroid-sensitive extraneuronal monoamine transporter (EMT) and steroid sensitivity of NE uptake in human bronchial artery and rabbit aorta (as a substitute for the limited supply of human bronchial artery). NE uptake was measured using a semiquantitative, sucrose-potassium phosphate-glyoxylic acid fluorescence method that we newly adapted for use in single cells. Both human bronchial arteries and rabbit aorta expressed messenger RNA for EMT, and steroids blocked NE uptake into freshly dissociated human bronchial arterial and rabbit aortic smooth-muscle cells (SMCs). In the latter, inhibition of NE uptake by steroids was not altered, either by a protein synthesis inhibitor (cycloheximide) or by a transcription inhibitor (actinomycin D), and corticosterone made membrane-impermeant by conjugation to bovine serum albumin inhibited NE uptake equipotently. These data show that NE uptake into bronchial arterial and rabbit aortic SMCs is sensitive to steroids, possibly mediated by EMT, and suggest a mechanism for GS-induced bronchial vasoconstriction.


Assuntos
Brônquios/metabolismo , Músculo Liso Vascular/metabolismo , Norepinefrina/farmacocinética , Proteínas de Transporte de Cátions Orgânicos , Esteroides/farmacologia , Animais , Aorta/metabolismo , Sequência de Bases , Brônquios/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Células Cultivadas , Corticosterona/farmacologia , Feminino , Humanos , Dados de Sequência Molecular , Músculo Liso Vascular/efeitos dos fármacos , Coelhos , Esteroides/metabolismo
15.
Am J Med Genet ; 103(1): 69-74, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11562937

RESUMO

Screenings for the genetic disorder alpha(1) antitrypsin deficiency (AAT Deficiency) have been one of two models: large screenings of general populations and small targeted detection programs in high-risk groups. The most appropriate screening and detection methodologies in terms of target populations, subject participation and yield of positive tests, however, have not been well defined. The major objective of this pilot study was to evaluate the effectiveness in terms of participation of two different AAT Deficiency detection programs using a self-administered fingerstick blood test. Individuals ages 30-60 under the care of a pulmonary physician and with a diagnosis of emphysema, COPD, chronic bronchitis, or bronchiectasis were the targeted population. Participants were offered AAT Deficiency testing in the pulmonary physician's office compared with testing offered through mail. Participation (i.e., frequency of subject participation in the detection program) of two different AAT Deficiency detection programs. Non-participation was due to fear of self-administered testing and research studies; women were more likely to participate than men. Eligible subjects were significantly more likely to participate when offered testing by their pulmonary physician in-office (83%) than mail-only (42%) (P < 0.02). Although self-administered genetic testing is available, highest participation in AAT Deficiency detection program was found when offered directly by the physician. This finding may have implications for screening and detection of other genetic diseases. Future studies need to evaluate the yield (i.e., frequency of positive tests) of these detection methodologies in highly targeted populations.


Assuntos
alfa 1-Antitripsina/genética , Adulto , Bronquiectasia/diagnóstico , Bronquiectasia/genética , Bronquiectasia/metabolismo , Bronquite/diagnóstico , Bronquite/genética , Bronquite/metabolismo , Doença Crônica , Enfisema/diagnóstico , Enfisema/genética , Enfisema/metabolismo , Feminino , Testes Genéticos , Heterozigoto , Homozigoto , Humanos , Pneumopatias Obstrutivas/diagnóstico , Pneumopatias Obstrutivas/genética , Pneumopatias Obstrutivas/metabolismo , Masculino , Pessoa de Meia-Idade , Projetos Piloto , alfa 1-Antitripsina/metabolismo
16.
J Asthma ; 38(1): 99-106, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11256560

RESUMO

This study investigated the relationship between parental self-efficacy and asthma-related morbidity. Participants included 139 parents of children (ages 5-8) who were diagnosed with asthma and were primarily from lower-income and minority backgrounds. Parents completed a 22-item measure of self-efficacy; factor analysis was conducted on this measure, yielding two factors: learned helplessness and self-efficacy. Correlational analyses indicated that higher scores on the learned helplessness factor were significantly related to increased asthma-related morbidity for the majority of morbidity variables. The self-efficacy factor was significantly related to days of school missed. Regression analyses conducted with the factor scores and the morbidity variables provide further support that the learned helplessness factor accounts for a significant amount of the variance in asthma morbidity for many of the variables studied, while the self-efficacy factor was related to only a few. Although improving health outcomes of children with asthma is a multifaceted process, the results of this study suggest that targeting parental self-efficacy, particularly with parents who are experiencing high levels of perceived learned helplessness, may be a helpful component of an intervention program with this population.


Assuntos
Asma/complicações , Saúde da Família , Pais , Autoeficácia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Análise de Regressão , Inquéritos e Questionários
17.
J Appl Physiol (1985) ; 90(2): 665-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11160067

RESUMO

The purpose of the present study was to determine the responsiveness of airway vascular smooth muscle (AVSM) as assessed by airway mucosal blood flow (Qaw) to inhaled methoxamine (alpha(1)-agonist; 0.6-2.3 mg) and albuterol (beta(2)-agonist; 0.2-1.2 mg) in healthy [n = 11; forced expiratory volume in 1 s, 92 +/- 4 (SE) % of predicted] and asthmatic (n = 11, mean forced expiratory volume in 1 s, 81 +/- 5%) adults. Mean baseline values for Qaw were 43.8 +/- 0.7 and 54.3 +/- 0.8 microl. min(-1). ml(-1) of anatomic dead space in healthy and asthmatic subjects, respectively (P < 0.05). After methoxamine inhalation, the maximal mean change in Qaw was -13.5 +/- 1.0 microl. min(-1). ml(-1) in asthmatic and -7.1 +/- 2.1 microl. min(-1). ml(-1) in healthy subjects (P < 0.05). After albuterol, the mean maximal change in Qaw was 3.0 +/- 0.8 microl. min(-1). ml(-1) in asthmatic and 14.0 +/- 1.1 microl. min(-1). ml(-1) in healthy subjects (P < 0.05). These results demonstrate that the contractile response of AVSM to alpha(1)-adrenoceptor activation is enhanced and the dilator response of AVSM to beta(2)-adrenoceptor activation is blunted in asthmatic subjects.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Albuterol/administração & dosagem , Asma/fisiopatologia , Metoxamina/farmacologia , Músculo Liso Vascular/inervação , Administração por Inalação , Agonistas alfa-Adrenérgicos/administração & dosagem , Agonistas Adrenérgicos beta/administração & dosagem , Adulto , Albuterol/farmacologia , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Masculino , Metoxamina/administração & dosagem , Pessoa de Meia-Idade , Músculo Liso Vascular/fisiopatologia , Circulação Pulmonar , Espaço Morto Respiratório , Mucosa Respiratória/irrigação sanguínea , Vasoconstrição , Vasodilatação
18.
Pediatr Pulmonol ; 30(4): 297-301, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015129

RESUMO

The increase in the prevalence, morbidity, and mortality of asthma among children over the last decade has been well documented, especially among low-income minority children. Hypotheses for the increases in morbidity and mortality include limited access to primary care services and the failure to recognize the presence and severity of asthma. The University of Miami Pediatric Mobile Clinic (Mobile Clinic) Asthma Intervention Program is designed to identify underserved asthmatic children at school and offer them culturally sensitive care. Nine elementary schools with low income, predominantly Hispanic and African-American populations regularly served by the Mobile Clinic, were chosen for study participation. All 5,800 students who were enrolled in kindergarten through third grade were given letters at the time of registration by their homeroom teachers about the asthma program. Caretakers who returned the questionnaire and reported that the student had asthma symptoms were invited to have the student undergo a medical evaluation in the Mobile Clinic. Over a 2-year period, caretakers of 423 students (7.3% of all students) expressed an interest in further evaluating their child's respiratory health. Of these, we enrolled and evaluated 154 in the Mobile Clinic's Asthma Intervention Program. The Mobile Clinic physicians identified 145 of the enrollees as having asthma. These results indicate that in elementary schools serving predominantly low-income minority populations, a large fraction of the asthmatic population (estimated prevalence, 6-10%) can be identified by a school-based letter. Further, in a subset of asthmatic students (children of interested caretakers), there is good agreement between caretaker responses and physician diagnosis of asthma. Since school attendance is mandatory, school-based methods may be an effective method for identifying low-income children with asthma.


Assuntos
Asma/epidemiologia , Unidades Móveis de Saúde , Serviços de Saúde Escolar , Negro ou Afro-Americano , Criança , Pré-Escolar , Feminino , Florida , Hispânico ou Latino , Humanos , Masculino , Pobreza , Prevalência
19.
Am J Respir Crit Care Med ; 162(4 Pt 2): S137, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11029381
20.
Phys Rev Lett ; 85(4): 788-91, 2000 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-10991399

RESUMO

Brittle fracture usually proceeds at crack driving forces which are larger than those needed to create the new fracture surfaces. This surplus can lead to faster crack propagation or to the onset of additional dissipation mechanisms. Dynamic fracture experiments on silicon single crystals reported here show several distinct transitions between different dissipation mechanisms. Cleavage fracture is followed by the propagation of a faceted crack front, which is finally followed by a path instability and the propagation of multiple cracks. The fracture surface qualitatively corresponds to the mirror, mist, and hackle morphology of amorphous materials. However, the corresponding fracture mechanisms, which remain largely unknown in the amorphous materials, can clearly be identified here.

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