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BACKGROUND: Alcohol dependence is common, yet highly undertreated. Smartphone applications (apps) have potential to enhance treatment accessibility and effectiveness, however evidence is limited, especially studies focussing on user experiences. The aim was to describe patient perceptions on the usability and acceptability of self-monitoring apps provided as treatment complement for alcohol dependence. METHODS: Individual semi-structured interviews were conducted through video or phone calls with 21 participants, recruited from a randomized controlled trial at a dependency clinic in Stockholm. The participants had used two specific apps for self-monitoring consumption ("Glasklart" and "iBAC") during 12 wk prior to the interviews. Data was analyzed using Qualitative Content Analysis. RESULTS: Two domains were identified: 1) Smartphone applications as facilitators to treatment, and 2) Barriers to smartphone application use. Using apps within the treatment context was believed to increase the accuracy of the reported consumption. Participants became more aware of their alcohol problem and described the apps as reinforcers that could increase both the motivation to change and the focus on the problem and commitment to treatment. The apps were further described as helpful to control alcohol consumption. However, app usage was constrained by technical problems, unfit app-specific features and procedures, and alcohol-related shame and stigma. DISCUSSION AND CONCLUSIONS: Self-monitoring alcohol apps have several beneficial features that can help assess, track, and control alcohol consumption, and improve communication with clinicians. The results indicate they can be useful complements to treatment for patients with alcohol dependence, but their use can be limited by different, foremost technical, issues.
Smartphone applications for self-monitoring of alcohol consumption may help provide accurate data, increase consumption awareness, focus, motivation, and perceived control;Smartphone applications for self-monitoring of alcohol consumption are considered helpful complements to alcohol treatment;The use of smartphone applications for self-monitoring of alcohol consumption can be constrained by technical problems, and unfit app-specific features and procedures.
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Alcoolismo , Aplicativos Móveis , Humanos , Alcoolismo/terapia , Smartphone , ComunicaçãoRESUMO
On 19 March 2020, California put in place Stay-At-Home orders to reduce the spread of SARS-CoV-2. As a result, decreases up to 50% in traffic occurred across the South Coast Air Basin (SoCAB). We report that, compared to the 19 March to 30 June period of the last 5 years, the 2020 concentrations of PM2.5 and NO x showed an overall reduction across the basin. O3 concentrations decreased in the western part of the basin and generally increased in the downwind areas. The NO x decline in 2020 (approximately 27% basin-wide) is in addition to ongoing declines over the last two decades (on average 4% less than the -6.8% per year afternoon NO2 concentration decrease) and provides insight into how air quality may respond over the next few years of continued vehicular reductions. The modest changes in O3 suggests additional mitigation will be necessary to comply with air quality standards.
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Ozone pollution affects human health, especially in urban areas on hot sunny days. Its basic photochemistry has been known for decades and yet it is still not possible to correctly predict the high ozone levels that are the greatest threat. The CalNex_SJV study in Bakersfield CA in May/June 2010 provided an opportunity to examine ozone photochemistry in an urban area surrounded by agriculture. The measurement suite included hydroxyl (OH), hydroperoxyl (HO2), and OH reactivity, which are compared with the output of a photochemical box model. While the agreement is generally within combined uncertainties, measured HO2 far exceeds modeled HO2 in NOx-rich plumes. OH production and loss do not balance as they should in the morning, and the ozone production calculated with measured HO2 is a decade greater than that calculated with modeled HO2 when NO levels are high. Calculated ozone production using measured HO2 is twice that using modeled HO2, but this difference in calculated ozone production has minimal impact on the assessment of NOx-sensitivity or VOC-sensitivity for midday ozone production. Evidence from this study indicates that this important discrepancy is not due to the HO2 measurement or to the sampling of transported plumes but instead to either emissions of unknown organic species that accompany the NO emissions or unknown photochemistry involving nitrogen oxides and hydrogen oxides, possibly the hypothesized reaction OH + NO + O2 â HO2 + NO2.
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OBJECTIVE: To examine the association between meeting behavioural goals and diabetes incidence over 10 years in a large, representative Swedish population. METHODS: Population-based prospective cohort study of 32,120 individuals aged 35 to 55 years participating in a health promotion intervention in Västerbotten County, Sweden (1990 to 2013). Participants underwent an oral glucose tolerance test, clinical measures, and completed diet and activity questionnaires. Poisson regression quantified the association between achieving six behavioural goals at baseline - body mass index (BMI) <25 kg/m(2), moderate physical activity, non-smoker, fat intake <30% of energy, fibre intake ≥15 g/4184 kJ and alcohol intake ≤20 g/day - and diabetes incidence over 10 years. RESULTS: Median interquartile range (IQR) follow-up time was 9.9 (0.3) years; 2211 individuals (7%) developed diabetes. Only 4.4% of participants met all 6 goals (n=1245) and compared to these individuals, participants meeting 0/1 goals had a 3.74 times higher diabetes incidence (95% confidence interval (CI)=2.50 to 5.59), adjusting for sex, age, calendar period, education, family history of diabetes, history of myocardial infarction and long-term illness. If everyone achieved at least four behavioural goals, 14.1% (95% CI: 11.7 to 16.5%) of incident diabetes cases might be avoided. CONCLUSION: Interventions promoting the achievement of behavioural goals in the general population could significantly reduce diabetes incidence.
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Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Comportamentos Relacionados com a Saúde , Adulto , Índice de Massa Corporal , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Atividade Motora , Análise de Regressão , Fatores de Risco , Fumar/epidemiologia , Inquéritos e Questionários , Suécia/epidemiologiaRESUMO
BACKGROUND: Alcohol habits in Sweden, assessed as sales and estimates of unrecorded consumption, have changed since joining the EU. Earlier studies using the Alcohol Use Disorders Identification Test (AUDIT) showed that reported consumption is consistent with sales data, which makes it possible to assess consumption according to sex and age. AIMS: This study reports the changes in alcohol habits between 2009 and 2014, a period starting a couple of years after Sweden joined the EU. METHOD: The AUDIT was sent to a random sample of the Swedish population aged between 17 and 80 years old. RESULTS: No statistically significant changes were shown in six age and sex groups. CONCLUSIONS: Alcohol habits have stabilised in Sweden but on a higher consumption level than before.
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Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/diagnóstico , Programas de Rastreamento/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comércio/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suécia/epidemiologia , Adulto JovemRESUMO
Recent laboratory studies have demonstrated that isoprene oxidation products can partition to atmospheric aerosols by reacting with condensed phase sulfuric acid, forming low-volatility organosulfate compounds. We have identified organosulfate compounds in free tropospheric aerosols by single particle mass spectrometry during several airborne field campaigns. One of these organosulfates is identified as the sulfate ester of IEPOX, a second generation oxidation product of isoprene. The patterns of IEPOX sulfate ester in ambient data generally followed the aerosol acidity and NO(x) dependence established by laboratory studies. Detection of the IEPOX sulfate ester was most sensitive using reduced ionization laser power, when it was observed in up to 80% of particles in the tropical free troposphere. Based on laboratory mass calibrations, IEPOX added > 0.4% to tropospheric aerosol mass in the remote tropics and up to 20% in regions downwind of isoprene sources. In the southeastern United States, when acidic aerosol was exposed to fresh isoprene emissions, accumulation of IEPOX increased aerosol mass by up to 3%. The IEPOX sulfate ester is therefore one of the most abundant single organic compounds measured in atmospheric aerosol. Our data show that acidity-dependent IEPOX uptake is a mechanism by which anthropogenic SO(2) and marine dimethyl sulfide emissions generate secondary biogenic aerosol mass throughout the troposphere.
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Aerossóis/análise , Poluentes Atmosféricos/análise , Butadienos/química , Hemiterpenos/química , Compostos Orgânicos/análise , Pentanos/química , Sulfatos/análise , Atmosfera/química , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Oxirredução , Estados UnidosRESUMO
BACKGROUND: Short-term trials conducted in adults with type 2 diabetes mellitus (T2DM) showed that reducing sedentary behaviour by performing regular short bouts of light-intensity physical activity enhances health. Moreover, support for reducing sedentary behaviour may be provided at a low cost via mobile health technology (mHealth). There are a wide range of mHealth solutions available including SMS text message reminders and activity trackers that monitor the physical activity level and notify the user of prolonged sitting periods. The aim of this study is to evaluate the effects of a mHealth intervention on sedentary behaviour and physical activity and the associated changes in health in adults with T2DM. METHODS: A dual-arm, 12-month, randomized controlled trial (RCT) will be conducted within a nationwide Swedish collaboration for diabetes research in primary health care. Individuals with T2DM (n = 142) and mainly sedentary work will be recruited across primary health care centres in five regions in Sweden. Participants will be randomized (1:1) into two groups. A mHealth intervention group who will receive an activity tracker wristband (Garmin Vivofit4), regular SMS text message reminders, and counselling with a diabetes specialist nurse, or a comparator group who will receive counselling with a diabetes specialist nurse only. The primary outcomes are device-measured total sitting time and total number of steps (activPAL3). The secondary outcomes are fatigue, health-related quality of life and musculoskeletal problems (self-reported questionnaires), number of sick leave days (diaries), diabetes medications (clinical record review) and cardiometabolic biomarkers including waist circumference, mean blood pressure, HbA1c, HDL-cholesterol and triglycerides. DISCUSSION: Successful interventions to increase physical activity among those with T2DM have been costly and long-term effectiveness remains uncertain. The use of mHealth technologies such as activity trackers and SMS text reminders may increase awareness of prolonged sedentary behaviour and encourage increase in regular physical activity. mHealth may, therefore, provide a valuable and novel tool to improve health outcomes and clinical management in those with T2DM. This 12-month RCT will evaluate longer-term effects of a mHealth intervention suitable for real-world primary health care settings. TRIAL REGISTRATION: ClinicalTrials.gov NCT04219800 . Registered on 7 January 2020.
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Diabetes Mellitus Tipo 2 , Telemedicina , Adulto , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Exercício Físico/fisiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Comportamento Sedentário , Postura SentadaRESUMO
The current work focuses on the detailed evolution of the chemical composition of both the gas- and aerosol-phase constituents produced from the OH-initiated photooxidation of naphthalene under low- and high-NO(x) conditions. Under high-NO(x) conditions ring-opening products are the primary gas-phase products, suggesting that the mechanism involves dissociation of alkoxy radicals (RO) formed through an RO(2) + NO pathway, or a bicyclic peroxy mechanism. In contrast to the high-NO(x) chemistry, ring-retaining compounds appear to dominate the low-NO(x) gas-phase products owing to the RO(2) + HO(2) pathway. We are able to chemically characterize 53-68% of the secondary organic aerosol (SOA) mass. Atomic oxygen-to-carbon (O/C), hydrogen-to-carbon (H/C), and nitrogen-to-carbon (N/C) ratios measured in bulk samples by high-resolution electrospray ionization time-of-flight mass spectrometry (HR-ESI-TOFMS) are the same as the ratios observed with online high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS), suggesting that the chemical compositions and oxidation levels found in the chemically-characterized fraction of the particle phase are representative of the bulk aerosol. Oligomers, organosulfates (R-OSO(3)), and other high-molecular-weight (MW) products are not observed in either the low- or high-NO(x) SOA; however, in the presence of neutral ammonium sulfate seed aerosol, an organic sulfonic acid (R-SO(3)), characterized as hydroxybenzene sulfonic acid, is observed in naphthalene SOA produced under both high- and low-NO(x) conditions. Acidic compounds and organic peroxides are found to account for a large fraction of the chemically characterized high- and low-NO(x) SOA. We propose that the major gas- and aerosol-phase products observed are generated through the formation and further reaction of 2-formylcinnamaldehyde or a bicyclic peroxy intermediate. The chemical similarity between the laboratory SOA and ambient aerosol collected from Birmingham, Alabama (AL) and Pasadena, California (CA) confirm the importance of PAH oxidation in the formation of aerosol within the urban atmosphere.
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Simultaneous in situ measurements of the concentrations of OH, HO(2), ClO, BrO, NO, and NO(2) demonstrate the predominance of odd-hydrogen and halogen free-radical catalysis in determining the rate of removal of ozone in the lower stratosphere during May 1993. A single catalytic cycle, in which the rate-limiting step is the reaction of HO(2) with ozone, accounted for nearly one-half of the total O(3) removal in this region of the atmosphere. Halogen-radical chemistry was responsible for approximately one-third of the photochemical removal of O(3); reactions involving BrO account for one-half of this loss. Catalytic destruction by NO(2), which for two decades was considered to be the predominant loss process, accounted for less than 20 percent of the O(3) removal. The measurements demonstrate quantitatively the coupling that exists between the radical families. The concentrations of HO(2) and ClO are inversely correlated with those of NO and NO(2). The direct determination of the relative importance of the catalytic loss processes, combined with a demonstration of the reactions linking the hydrogen, halogen, and nitrogen radical concentrations, shows that in the air sampled the rate of O(3) removal was inversely correlated with total NOx, loading.
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Large particles containing nitric acid (HNO3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.
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BACKGROUND: The sensitivity and specificity of exercise testing have never been studied simultaneously against an objective quantification of arterial stenosis. Aims were to define the sensitivity and specificity of several exercise tests to detect peripheral artery disease (PAD), and to assess whether or not defined criteria defined in patients suspected of having a PAD show a difference dependent on the resting ABI. METHODS: In this prospective study, consecutive patients with exertional limb pain referred to our vascular center were included. All patients had an ABI, a treadmill exercise-oximetry test, a second treadmill test (both 10% slope; 3.2km/h speed) with post-exercise pressures, and a computed-tomography-angiography (CTA). The receiver-operating-characteristic curve was used to define a cut-off point corresponding to the best area under the curve (AUC; [CI95%]) to detect arterial stenosis ≥50% as determined by the CTA. RESULTS: Sixty-three patients (61+/-11 years-old) were included. Similar AUCs from 0.72[0.63-0.79] to 0.83[0.75-0.89] were found for the different tests in the overall population. To detect arterial stenosis ≥50%, cut-off values of ABI, post-exercise ABI, post-exercise ABI decrease, post-exercise ankle pressure decrease, and distal delta from rest oxygen pressure (DROP) index were ≤0.91, ≤0.52, ≥43%, ≥20mmHg and ≤-15mmHg, respectively (p<0.01). In the subset of patients with an ABI >0.91, cut-off values of post-exercise ABI decrease (AUC = 0.67[0.53-0.78]), and DROP (AUC = 0.67[0.53-0.78]) were ≥18.5%, and ≤-15mmHg respectively (p<0.05). CONCLUSION: Resting ABI is as accurate as exercise testing in patients with exertional limb pain. Specific exercise testing cut-off values should be used in patients with normal ABI to diagnose PAD.
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Teste de Esforço/métodos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico , Idoso , Índice Tornozelo-Braço/estatística & dados numéricos , Monitorização Transcutânea dos Gases Sanguíneos , Angiografia por Tomografia Computadorizada , Teste de Esforço/estatística & dados numéricos , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Sensibilidade e EspecificidadeRESUMO
NASA's Orbiting Carbon Observatory-2 (OCO-2) mission was motivated by the need to diagnose how the increasing concentration of atmospheric carbon dioxide (CO2) is altering the productivity of the biosphere and the uptake of CO2 by the oceans. Launched on 2 July 2014, OCO-2 provides retrievals of the column-averaged CO2 dry-air mole fraction ([Formula: see text]) as well as the fluorescence from chlorophyll in terrestrial plants. The seasonal pattern of uptake by the terrestrial biosphere is recorded in fluorescence and the drawdown of [Formula: see text] during summer. Launched just before one of the most intense El Niños of the past century, OCO-2 measurements of [Formula: see text] and fluorescence record the impact of the large change in ocean temperature and rainfall on uptake and release of CO2 by the oceans and biosphere.
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Atmosfera/química , Ciclo do Carbono , Dióxido de Carbono/análise , Mudança Climática , Clorofila/análise , Fluorescência , Plantas/química , Estações do AnoRESUMO
Formation of organic nitrates (RONO2) during oxidation of biogenic volatile organic compounds (BVOCs: isoprene, monoterpenes) is a significant loss pathway for atmospheric nitrogen oxide radicals (NOx), but the chemistry of RONO2 formation and degradation remains uncertain. Here we implement a new BVOC oxidation mechanism (including updated isoprene chemistry, new monoterpene chemistry, and particle uptake of RONO2) in the GEOS-Chem global chemical transport model with â¼25 × 25 km2 resolution over North America. We evaluate the model using aircraft (SEAC4RS) and ground-based (SOAS) observations of NOx, BVOCs, and RONO2 from the Southeast US in summer 2013. The updated simulation successfully reproduces the concentrations of individual gas- and particle-phase RONO2 species measured during the campaigns. Gas-phase isoprene nitrates account for 25-50% of observed RONO2 in surface air, and we find that another 10% is contributed by gas-phase monoterpene nitrates. Observations in the free troposphere show an important contribution from long-lived nitrates derived from anthropogenic VOCs. During both campaigns, at least 10% of observed boundary layer RONO2 were in the particle phase. We find that aerosol uptake followed by hydrolysis to HNO3 accounts for 60% of simulated gas-phase RONO2 loss in the boundary layer. Other losses are 20% by photolysis to recycle NOx and 15% by dry deposition. RONO2 production accounts for 20% of the net regional NOx sink in the Southeast US in summer, limited by the spatial segregation between BVOC and NOx emissions. This segregation implies that RONO2 production will remain a minor sink for NOx in the Southeast US in the future even as NOx emissions continue to decline.
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BACKGROUND: Endothelin-converting enzyme-1 (ECE-1) processes big endothelin-1 (ET-1) to ET-1, a peptide implicated in atheroma formation. ECE-1 exists in 2 isoforms (ECE-1alpha and ECE-1beta), the result of alternative splicing of a common gene. Neutral endopeptidase (NEP) is a genetically distinct metallopeptidase that degrades the natriuretic peptides. These peptides mediate antiproliferative and vasodilating actions. We sought to demonstrate the distribution of the 2 ECE-1 isoforms in experimental atherosclerosis, to determine the effects of chronic NEP-I on plasma cGMP concentrations, vascular wall ECE-1 activity, and ET-1 concentration, and to correlate these actions with atheroma formation. Our hypothesis was that chronic NEP-I, in association with augmented cGMP, would inhibit ECE-1 conversion of big ET-1 to active ET-1, thus reducing tissue ET-1 concentrations and associated atheroma formation. METHODS AND RESULTS: Cholesterol-fed New Zealand White rabbits (n=8, 1% cholesterol diet) and NEP-I-treated cholesterol-fed New Zealand White rabbits (n=8; candoxatril, 30 mg/kg per day, Pfizer) were euthanized after 8 weeks of feeding. ECE-1alpha and ECE-1beta immunoreactivity was present in the aortas of both groups. Compared with control values, plasma cGMP concentrations were increased (2.8+/-0.6 versus 8.4+/-1.2 pmol/mL, P<0.05), ECE-1 activity was attenuated (68+/-3% versus 32+/-8%, P<0. 05), aortic tissue ET-1 concentrations were reduced (4.6+/-0.5 versus 3.2+/-0.3 pg/mg protein, P<0.05), and atheroma formation was attenuated (62+/-6% versus 34+/-5%, P<0.01) by NEP-I. CONCLUSIONS: These studies suggest that ECE-1 is present and functionally active in the vascular wall in atherosclerosis. Inhibition of ECE-1 by NEP-I represents a novel approach to interruption of the endothelin system in this cardiovascular disease state.
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Arteriosclerose/enzimologia , Ácido Aspártico Endopeptidases/metabolismo , Isoenzimas/metabolismo , Neprilisina/antagonistas & inibidores , Animais , Aorta/enzimologia , Ácido Aspártico Endopeptidases/análise , Fator Natriurético Atrial/metabolismo , Doença Crônica , GMP Cíclico/metabolismo , Dieta Aterogênica , Modelos Animais de Doenças , Endotelina-1/metabolismo , Enzimas Conversoras de Endotelina , Endotelinas/metabolismo , Técnicas In Vitro , Isoenzimas/análise , Masculino , Metaloendopeptidases , Neprilisina/metabolismo , Precursores de Proteínas/metabolismo , Coelhos , Fatores de Tempo , Vasoconstrição/fisiologiaRESUMO
Left ventricular, and possibly also right ventricular, mass is an important determinant of prognosis in cardiovascular disease. Consequently, noninvasive estimation of ventricular mass may be an important clinical investigation. The ideal technique for this purpose would be widely available and accurate, employ short study times and avoid exposure to contrast agents and radiation. Conventional nuclear magnetic resonance (NMR) imaging fulfills most of these criteria, but it is time-consuming and expensive. Moreover, its accuracy in estimating right ventricular mass has yet to be assessed. Accordingly, high speed NMR imaging using the snapshot gradient echo technique was used to assess right and left ventricular mass in 10 dogs and the results were compared with values obtained at autopsy, which ranged from 26.1 to 52.9 and 61 to 119.8 g, respectively. The mean absolute difference between the NMR imaging estimates and autopsy findings was 2 +/- 1.2 g (range 0.4 to 4.2) for right ventricular mass and 4.4 +/- 1.7 g (range 1.8 to 6.6) for left ventricular mass. Total NMR imaging time was less than or equal to 5 min. These data demonstrate that high speed NMR imaging can be used to accurately estimate right as well as left ventricular mass.
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Ventrículos do Coração/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Animais , Cardiomegalia/diagnóstico , Cães , Função Ventricular/fisiologiaRESUMO
OBJECTIVES: We sought to define the vascular actions of the cardiac hormone brain natriuretic peptide (BNP) on cellular proliferation and cyclic guanosine monophosphate (cGMP) in human aortic vascular smooth muscle cells (HAVSMCs). Secondly, we investigated BNP and acetylcholine (ACh) vasorelaxations in aortic rings from normal and atherosclerotic rabbits in the presence and absence of long-term oral inhibition of neutral endopeptidase (NEP). BACKGROUND: The vascular actions of BNP are not well defined, despite the presence of its receptor in vascular smooth muscle and the upregulation of NEP, the ectoenzyme that degrades BNP, in the vascular wall in atherosclerosis. METHODS: HAVSMCs stimulated with fetal calf serum (FCS) were pulsed with bromodeoxyuridine (BrdU) with and without BNP. The HAVSMCs were incubated in the presence and absence of BNP to assess cGMP. Vasorelaxations to BNP and ACh were assessed in rings in normal and atherosclerotic rabbits in the presence and absence of long-term oral inhibition of NEP, together with assessment of atheroma formation. RESULTS: FCS-stimulated BrdU uptake in HAVSMCs was suppressed with BNP. BNP potentiated cGMP in HAVSMCs. BNP resulted in potent vasorelaxation in normal isolated aortic rings, which were impaired in atherosclerotic versus normal rabbits and preserved with NEP inhibition, which also decreased atheroma formation. Relaxations to ACh, which were also impaired in atherosclerosis, were preserved with inhibition of NEP. CONCLUSIONS: We conclude that BNP potently inhibits vascular smooth muscle cell proliferation and potentiates the generation of cGMP. BNP potently relaxes the normal rabbit aorta, and this response is impaired in atherosclerosis but preserved with inhibition of NEP, together with a reduction in atheroma formation and preservation of relaxations to ACh.
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Arteriosclerose/fisiopatologia , Músculo Liso Vascular/efeitos dos fármacos , Peptídeo Natriurético Encefálico/farmacologia , Neprilisina/metabolismo , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/enzimologia , Aorta/patologia , Arteriosclerose/enzimologia , Arteriosclerose/patologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Fenilefrina/farmacologia , Coelhos , Vasoconstritores/farmacologia , Vasodilatadores/farmacologiaRESUMO
OBJECTIVE: To determine whether Dendroaspis natriuretic peptide (DNP), a novel peptide isolated from the venom of the Dendroaspis angusticeps snake that contains a 17-amino acid disulfide ring structure similar to that in atrial, brain, and C-type natriuretic peptides, is present in normal human plasma and myocardium and whether, like the other natriuretic peptides, DNP-like immunoreactivity (DNP-LI) is activated in human congestive heart failure (CHF). MATERIAL AND METHODS: Circulating DNP-LI was assessed in 19 normal human subjects and 19 patients with CHF (New York Heart Association class III or IV) with a specific and sensitive radioimmunoassay for DNP with no cross-reactivity with the other natriuretic peptides. Immunohistochemical studies that used polyclonal rabbit anti-DNP antiserum were performed on human atrial myocardial tissue obtained from four patients with end-stage CHF who were undergoing cardiac transplantation and from three donor hearts at the time of transplantation. RESULTS: We report that DNP-LI circulates in normal human plasma and is present in the normal atrial myocardium. In addition, DNP-LI is increased in the plasma of patients with CHF. CONCLUSION: This study demonstrates, for the first time, the presence of a DNP-like peptide in normal human plasma and in the atrial myocardium. Additionally, these studies demonstrate increased plasma DNP-LI in human CHF. These results support the possible existence of an additional new natriuretic peptide in humans, which may have a role in the neurohumoral activation that characterizes human CHF.
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Venenos Elapídicos/sangue , Venenos Elapídicos/imunologia , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/imunologia , Peptídeos/sangue , Peptídeos/imunologia , Animais , Estudos de Casos e Controles , Venenos Elapídicos/análise , Venenos Elapídicos/química , Átrios do Coração/química , Humanos , Soros Imunes , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos/análise , Peptídeos/química , Coelhos , Radioimunoensaio , Índice de Gravidade de DoençaRESUMO
OBJECTIVE: The cytokine tumor necrosis factor alpha (TNF-alpha) is an important regulator of bone metabolism. Polymorphisms in the promoter region of the TNF-alpha gene at positions -308 and -863 have been identified. We investigated whether these polymorphisms and circulating TNF-alpha levels were related to bone mineral density and bone area in adolescent girls. DESIGN: Bone mineral density (BMD), bone area (BA), anthropometric characteristics and biochemical analyses were measured in adolescent girls and compared with regard to TNF-alpha genotype. METHODS: Allelic variants of the TNF-alpha gene in 97 girls, aged 16.9+/-1.2 years (mean+/-S.D.), were identified using polymerase chain reaction and the restriction endonucleases NcoI and TaiI. Bone mineral density and bone area of the femoral neck, lumbar spine and total body were measured using dual energy X-ray absorptiometry. RESULTS: Carriers of the rare -863 A allele (n=25) had higher body weight (P=0.03), lumbar spine BMD (P=0.02), and larger total BA (P=0.03), femoral neck area (P<0.05), and lumbar spine area (P=0.01). The independent predictors of BMD and BA were investigated using multiple regression. The TNF-alpha-863 genotypes (beta=0.18, P=0.03) and the TNF-alpha plasma levels (beta=0.19, P=0.04) independently predicted BA of the lumbar spine but not BA or BMD of any other measured sites. No statistically significant differences in body constitution parameters, biochemical parameters, bone density, or bone area at the measured skeletal sites were found when comparing the groups defined by the allelic variants at position -308 (P=0.17-0.84). CONCLUSIONS: We found the TNF-alpha-863 polymorphism and the TNF-alpha plasma levels to be independent predictors of lumbar spine area in healthy Caucasian adolescent females.
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Vértebras Lombares/anatomia & histologia , Polimorfismo Genético , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/genética , População Branca/genética , Adolescente , Alelos , Antropometria , Densidade Óssea , Feminino , Previsões , Genótipo , Heterozigoto , Humanos , Vértebras Lombares/metabolismo , Análise Multivariada , Valores de ReferênciaRESUMO
Previous research has indicated that the relation between adolescent and adult alcohol habits is not very strong. The objective of the present study was to illustrate associations between different aspects of alcohol habits from adolescence to early middle age in a normal, representative Swedish birth cohort of male (n = 122) and female (n = 90) participants. The sample was prospectively followed by means of self-reports on drinking habits at ages 18, 25, and 36. The results show that heavy drinking at age 18 and frequent intoxication at age 25 substantially increase the risk of heavy consumption at age 36 but that hazardous alcohol habits at either age 18 or 25 alone cannot be considered a substantial risk factor.
Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/psicologia , Hábitos , Adolescente , Adulto , Alcoolismo/diagnóstico , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , SuéciaRESUMO
BACKGROUND: With currently available effective interventional methods to treat superficial venous insufficiency, it becomes particularly important to have a simple and reliable method to evaluate the location and severity of venous reflux. To date, there are few studies that evaluated plethysmography with and without tourniquet application to differentiate superficial from deep venous incompetence. OBJECTIVES: To determine if strain gauge plethysmography (SGP) with and without tourniquet application can be used to distinguish between the superficial and deep venous components of venous incompetence. METHODS: We conducted a prospective study using SGP with and without tourniquet application and duplex ultrasound (duplex US) to assess the severity and location of venous incompetence in 62 patients (85 limbs, 42 women, with an age range of 32-81 years) referred to our vascular laboratory for haemodynamic evaluation. Based on duplex US results, patients were diagnosed with superficial (SVI), deep and superficial (mixed) and deep vein incompetence (DVI). RESULTS: Mixed incompetence was the most common type. Twenty-three out of 33 limbs in the SVI group normalized their refill rate (RR) with tourniquet application (69.6%). Normalization of the RR with tourniquet application was less common in the mixed (n: 17 out of 40, 42.5%) and DVI (n: 2 out of 6, 33.3%) groups. CONCLUSION: SGP with tourniquet application is a simple and fast technique that can identify patients with SVI, based on RR improvement, who probably would benefit more from ablation procedures. Further studies evaluating impact of SGP with tourniquet test results on clinical outcome of SVI invasive treatment are warranted.