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1.
Chest ; 160(2): 470-480, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33607083

RESUMO

BACKGROUND: Pulmonary endothelial damage has been shown to precede the development of emphysema in animals, and vascular changes in humans have been observed in COPD and emphysema. RESEARCH QUESTION: Is intraparenchymal vascular pruning associated with longitudinal progression of emphysema on CT imaging or decline in lung function over 5 years? STUDY DESIGN AND METHODS: The Genetic Epidemiology of COPD Study enrolled ever smokers with and without COPD from 2008 through 2011. The percentage of emphysema-like lung, or "percent emphysema," was assessed at baseline and after 5 years on noncontrast CT imaging as the percentage of lung voxels < -950 Hounsfield units. An automated CT imaging-based tool assessed and classified intrapulmonary arteries and veins. Spirometry measures are postbronchodilator. Pulmonary arterial pruning was defined as a lower ratio of small artery volume (< 5 mm2 cross-sectional area) to total lung artery volume. Mixed linear models included demographics, anthropomorphics, smoking, and COPD, with emphysema models also adjusting for CT imaging scanner and lung function models adjusting for clinical center and baseline percent emphysema. RESULTS: At baseline, the 4,227 participants were 60 ± 9 years of age, 50% were women, 28% were Black, 47% were current smokers, and 41% had COPD. Median percent emphysema was 2.1 (interquartile range, 0.6-6.3) and progressed 0.24 percentage points/y (95% CI, 0.22-0.26 percentage points/y) over 5.6 years. Mean FEV1 to FVC ratio was 68.5 ± 14.2% and declined 0.26%/y (95% CI, -0.30 to -0.23%/y). Greater pulmonary arterial pruning was associated with more rapid progression of percent emphysema (0.11 percentage points/y per 1-SD increase in arterial pruning; 95% CI, 0.09-0.16 percentage points/y), including after adjusting for baseline percent emphysema and FEV1. Arterial pruning also was associated with a faster decline in FEV1 to FVC ratio (-0.04%/y per 1-SD increase in arterial pruning; 95% CI, -0.008 to -0.001%/y). INTERPRETATION: Pulmonary arterial pruning was associated with faster progression of percent emphysema and more rapid decline in FEV1 to FVC ratio over 5 years in ever smokers, suggesting that pulmonary vascular differences may be relevant in disease progression. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT00608764; URL: www.clinicaltrials.gov.


Assuntos
Endotélio Vascular/patologia , Artéria Pulmonar/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Progressão da Doença , Endotélio Vascular/diagnóstico por imagem , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/genética , Testes de Função Respiratória , Fumantes , Tomografia Computadorizada por Raios X
3.
5.
Proc IEEE Int Symp Biomed Imaging ; 2019: 1229-1233, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32454950

RESUMO

Computerized fluid dynamics models of particle deposition in the human airways are used to characterize deposition patterns that enable the study of lung diseases like asthma and chronic obstructive pulmonary disease (COPD). Despite this fact, the influence of patient-specific geometry on the deposition efficiency and patterns is not well documented nor modeled. In part, this is due to the complexity of simulating the full Computational Fluid Dynamics (CFD) solution in patient-specific airway geometries, a factor that becomes a major hurdle for patient-specific studies given the complexity of the geometry of human lungs and their related airflow. In this paper, we present an approximation method based on neural networks to the Navier-Stokes equations that govern airway flow in a Physiologically Realistic Bifurcation (PRB) model for the conducting region of a single generation human airway branch. The flow distribution and deposition of tobacco particles have been simulated for the inspiratory regime using ANSYS Fluent and a neural network has been trained to regress the mean velocity and mass flow components. Our results show that the approximation works well under the modeled assumptions and the serial application of this model to a two-generation airway geometry provides reasonable approximations.

6.
Eur J Vasc Endovasc Surg ; 53(3): 347-353, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28089084

RESUMO

OBJECTIVE: Thoraco-abdominal aortic aneurysm (TAAA) repair is a complex procedure performed in patients at high cardiovascular risk. High volume intra-operative bleeding is often recorded, and the amount of intra-operative blood product transfusion is associated with relevant morbidity and mortality. The aim of the study was to identify pre-operative predictors of intra-operative large volume blood transfusions (LVBT) to stratify patients pre-operatively. METHODS: This was a retrospective analysis of prospectively collected data of all patients who underwent open TAAA surgery at San Raffaele Scientific Institute from January 2009 to December 2015. Intra-operative red blood cell (RBC) transfusions were administered to maintain a hematocrit of at least 30%. A LVBT was defined as a transfusion of at least four RBC units, corresponding to 1000 mL. RESULTS: The study population included 428 patients: 260 (61%) received fewer than 4 RBC units, and 168 (39%) were transfused with at least 4 RBC units. In patients who underwent LVBT, higher mortality was observed after surgery (p=.003), longer intensive care unit admission (p=.004), and longer mechanical ventilation compared with less transfused patients (p=.0002). The patients who received fewer units were administered a higher dose of heparin during the surgical operation compared with patients of the LVBT group: 3400±1100 vs. 2900±1300 IU (international units) (p=.0004). Pre-operative chronic renal failure (OR 1.8), the pre-operative haemoglobin value (OR 0.8), and the need for urgent or emergent surgery (OR 3.15) were independent predictors of LVBT on multivariate analysis. CONCLUSIONS: The identification of patients at risk of intra-operative LVBT during TAAA surgery is critical as these patients experience a worse outcome. Nevertheless, only few independent predictors are available for clinical practice.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Eritrócitos , Procedimentos Cirúrgicos Vasculares , Idoso , Aneurisma da Aorta Torácica/mortalidade , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/mortalidade , Feminino , Hematócrito , Humanos , Itália , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
7.
Water Sci Technol ; 60(4): 1041-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19700843

RESUMO

The paper deals with the results obtained as nitrogen removal and energy savings in a wastewater treatment plant located in the Province of Trento where the vineyards grow on about 1,500 ha (19% of total vineyards of the Province). In the plant the municipal and pre-treated winery wastewater were co-treated. The optimal effluent quality and the reduction of energy consumption were achieved changing the total oxidation process to an alternate cycles (AC) one and applying a remote control system for three months. The characterization of the influent highlighted a remarkable variability of the mass loads mainly determined by the cyclic winemaking periods. The AC application allowed the system to cope with the intense variations of influent nitrogen loadings and to obtain a stable quality of the effluent with an average TN concentration less than 10 mg NL(-1). The nitrogen loading rate (NLR) up to 0.227 Kg TN m(-3) d(-1) was tolerated by the elevated AC control level device to assure successful denitrification performances (from 70% to 90%) also in conditions of COD/TN lower than 7. Comparing the AC with the pre AC conditions, a total energy saving in the range of 13-23% was estimated. Moreover, the specific energy consumptions were reduced to 59% despite the increment of the influent mass loadings.


Assuntos
Resíduos Industriais/análise , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Vinho , Aerobiose , Anaerobiose , Biodegradação Ambiental , Eletricidade , Nitritos/análise , Nitrogênio/análise , Oxigênio/isolamento & purificação , Compostos de Amônio Quaternário/análise
8.
Water Sci Technol ; 58(4): 831-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18776618

RESUMO

The paper deals with the real application of a strategy, based on process control automation and remote on-line supervision, for the wastewater treatment in a piedmont. Three existing small wastewater treatment plants were selected to be upgraded and to be included into a network remotely supervised. Further, the potentialities of the process control automation were enhanced by the appropriate upgrading of the whole plant. A consolidated alternating nitrification and denitrification process was applied for the biological treatment. The selected plants well represent the area of Autonomous Province of Trento because they are characterized by remarkable seasonal fluctuation. After five months of experimentation data processed show the real stable high quality of the treated effluent in terms of total nitrogen content. Moreover, the power requirements are significantly reduced according the correct energy policy. The performances of the new biological process applied and the economical balance, put in evidence the gain by chosing the AC technology for upgrading small WWTPs.


Assuntos
Reatores Biológicos , Conservação dos Recursos Naturais/métodos , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Anaerobiose , Itália , Reprodutibilidade dos Testes
9.
Water Sci Technol ; 56(2): 111-20, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17849985

RESUMO

In most cases of winery effluent, the heavy metal content, especially zinc (Zn) and copper (Cu), does not meet the limits for the discharge as imposed by the most restrictive regulations at international level (0.4 mgCu/L and 1.0 mgZn/L in the Italian regulations). An alternative for the reduction of Cu and Zn is the on-site pre-treatment of wastewater at the winery in order to meet the limits for the discharge into the public sewerage. The purpose of this study is to evaluate the effectiveness of a pre-treatment based on chemical precipitation with chelating agents (TMT: 2,4,6-trimercaptotriazine), for the reduction of Cu and Zn from raw winery wastewater. The chemical precipitation was optimised at lab-scale through jar tests in order to evaluate the optimal dosages. An average dosage equal to 0.84 mL of TMT (15%) for 1 mg of Cu removed was estimated. Furthermore, the efficiency of the on-site chemical pre-treatment was investigated at pilot scale. The results confirmed the feasibility of using TMT treatment for the reduction of Cu and Zn in order to meet the limits for discharge into the sewerage. Contextually to the removal of heavy metals, the chemical pre-treatment allowed us to obtain the reduction of particulate COD and TSS. Finally, the costs for the operation and the management of the on-site pre-treatment were evaluated.


Assuntos
Resíduos Industriais/prevenção & controle , Metais Pesados/isolamento & purificação , Purificação da Água/métodos , Vinho , Precipitação Química , Cobre/isolamento & purificação , Zinco/isolamento & purificação
10.
Rev. Clín. Ortod. Dent. Press ; 5(5): 71-78, out.-nov. 2006. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-519772

RESUMO

A biomecânica ortodôntica utiliza vários sistemas de forças que têm como objetivo promover a movimentação dentária de forma mais fisiológica possível. Os elásticos em cadeia são os mais utilizados para este propósito e suas principais aplicações clínicas incluem o fechamento de espaços em geral, retração de caninos, tracionamentos, correção de giroversões e desvios da linha média. Estes materiais vêm se destacando em virtude de suas vantagens, em relação aos demais sistemas de forças existentes, como a fácil aplicação, baixo custo, pouco tempo de trabalho do profissional, geram forças leves, são confortáveis para o paciente e não necessitam da cooperação de mesmo. Porém, possuem deficiências, sendo a principal a incapacidade de manter níveis de força contínuos após um período de tempo. Uma série de fatores pode contribuir no desempenho destes elásticos. O objetivo deste artigo foi fazer uma revisão da literatura, buscando quais fatores podem influenciar, de forma significativa, o desempenho clínico dos elásticos em cadeia, além de exemplificar suas principais aplicações clínicas. Concluiu-se que apenas o tipo de matéria prima empregado, método de fabricação, condições de armazenamento e o meio a que são expostas as cadeias elastoméricas podem influenciar de forma significativa o desempenho clínico deste materiais. Já os procedimentos de desinfecção e esterilização, diferentes cores e marcas comerciais, variações na temperatura e pH, exposição a soluções tópicas de fosfato de flúor acidulado, procedimentos de pré-estiramento, tempo de distensão, tipo de cadeia elastomérica e forma de adaptação dos elásticos aos braquetes não alteram significativamente o desempenho clínico destes materiais.


Assuntos
Elastômeros/uso terapêutico
11.
Water Sci Technol ; 51(1): 71-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15771101

RESUMO

The treatment of winery wastewater was performed at full-scale applying a two-stage fixed bed biofilm reactor (FBBR) system for the discharge in the sewerage. The results of the first year of operation at the full-scale plant are presented. Values of removed organic loads and effluent concentrations were interpreted on the basis of the COD fractionation of influent wastewater assessed through respirometric tests. The average removal efficiency of total COD was 91 %. It was not possible to reach an higher efficiency because of the unbiodegradable soluble fraction of COD (about 10% of total COD on average during the whole year), that cannot be removed by biological process or settling. Due to the high empty space offered by the plastic carriers, FBBRs did not require backwashing during the seasonal operationing period of the plant (September-March). In comparison with other treatment systems the FBBR configuration allows one to ensure a simple management, to obtain high efficiency also in the case of higher fluctuations of flow and loads and to guarantee a good settleability of the sludge, without bulking problems.


Assuntos
Biofilmes , Eliminação de Resíduos Líquidos/métodos , Vinho , Reatores Biológicos , Desenho de Equipamento , Indústrias , Estações do Ano , Movimentos da Água , Poluentes da Água/isolamento & purificação , Poluentes da Água/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-14524684

RESUMO

The aim of this research was the application of a biofilm system for the upgrading of a full-scale overloaded activated sludge MWWTP using the MBBR (Moving Bed Biofilm Reactor) technology. The choice of this fixed biomass system appeared appropriate because it offers several advantages including good potential in nitrification process, easiness of management and above all, the possibility to use the existing tank with very few modifications. MBBR system counts only few full-scale plants in Italy at the moment, thus a pilot-scale experimentation was preliminarily carried out. The acquired parameters were used for the fullscale MWWTP upgrading. The upgrading of the activated sludge reactor in the MBBR system has given (1) a relevant increase in the flowrate treated up to 60%; (2) a good efficiency in organic carbon removal and nitrification, equal to 88% and 90% respectively, with HRTs of 5.5-7 h; (3) the overcoming of the hydraulic overload of the secondary settler, applying a lamellar settler. It was observed a good correlation between the results obtained at pilot-scale and those observed in the full-scale plant.


Assuntos
Reatores Biológicos , Esgotos/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Biofilmes , Nitrogênio/metabolismo , Compostos Orgânicos/isolamento & purificação , Movimentos da Água
13.
Water Sci Technol ; 48(11-12): 169-77, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14753533

RESUMO

Tourists visiting mountain refuges in the Alps have increased significantly in the last decade and the number of refuges and huts at high altitude too. In this research the results of an intensive monitoring of a wastewater treatment plant (WWTP) for a tourist mountain refuge located at 2,981 m a.s.l. are described. Two biofilm reactors were adopted: (a) a Moving Bed Biofilm Reactor (MBBR); (b) a submerged Fixed Bed Biofilm Reactor (FBBR). The aims of this research were: (i) the evaluation of the main parameters characterising the processes and involved in the design of the wastewater plants, in order to compare advantages and disadvantages of the two tested alternatives; (ii) the acquisition of an adequate knowledge of the problems connected with the wastewater treatment in alpine refuges. The main results have been: (i) a quick start-up of the biological reactors obtainable thanks to a pre-colonization before the transportation of the plastic carriers to the refuge at the beginning of the tourist season; (ii) low volume and area requirement; (iii) significantly higher removal efficiency compared to other fixed biomass systems, such as trickling filters, but the energy consumption is higher.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Altitude , Biofilmes , Biomassa , Conservação dos Recursos Naturais , Itália , Estações do Ano , Pele , Suíça , Viagem
14.
Immunopharmacol Immunotoxicol ; 21(3): 551-64, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10466079

RESUMO

In this study we evaluated the maternal cell-mediated immune aspects of preeclampsia in terms of phagocytosis and killing of monocytes and polymorphonuclear cells. To evaluate the contribution of cytokines (Cks) in the pathophysiology of preeclampsia, we investigated the plasma levels of interferon-gamma (IFN-gamma), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), respectively, by an enzyme-linked immunosorbent assay. Data showed that phagocytic and killing activities of monocytes were depressed in preeclamptic and normal pregnancies. At the same time, IFN-gamma plasma levels were undectable in both groups. Conversely, we detected significant levels of TNF-alpha in plasma from preeclamptic and normal pregnancies. Moreover, since in three preeclamptic patients the onset of severe preeclampsia was associated with a sharp increased of TNF-alpha plasma levels, we suggest that an increased production of this CK may be implicated in the pathophysiology of preeclampsia.


Assuntos
Interferon gama/sangue , Interleucina-6/sangue , Pré-Eclâmpsia/imunologia , Fator de Necrose Tumoral alfa/análise , Adulto , Feminino , Humanos , Imunidade Inata , Fagocitose , Gravidez
15.
Headache ; 38(6): 465-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9664752

RESUMO

Thirty-two patients suffering from migraine without aura were assessed during in interictal period to evaluate the contribution of cytokines to the pathophysiology of migraine. To this end, plasma levels of IFN-gamma, IL-4, IL-5, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA) techniques. Plasma levels of both IFN-gamma and IL-10 were not increased in the patients and did not differ significantly from healthy controls. Of interest, we observed a strong increase of IL-5 levels in 84.3% as well as increased IL-4 levels in 37.5% of patients with migraine without aura. These results suggests a preferential enhancement of some Th2-type cytokines, and may support the growing arguments of an immunoallergic mechanism in the pathophysiology of migraine.


Assuntos
Citocinas/sangue , Interleucina-4/sangue , Interleucina-5/sangue , Transtornos de Enxaqueca/sangue , Adulto , Feminino , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/imunologia
16.
J Gastroenterol Hepatol ; 5(6): 633-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1966598

RESUMO

Hepatic fibroplasia seems to play an important role in the course of primary liver cancer (PLC) since, for instance, encapsulated and fibrolamellar hepatocellular carcinomas show a definitely better prognosis. In this study, serum procollagen III amino-terminal peptide (PIIIP) levels, which reflect synthesis and release of procollagen type III, were measured with the aim of assessing hepatic fibrogenesis in PLC patients and determining whether serum PIIIP levels play a diagnostic or prognostic role in PLC. Twenty-five patients with PLC, 74 patients with cirrhosis and 38 healthy volunteers were studied. Serum PIIIP levels were determined by a radioimmunoassay (RIA) method. In PLC patients PIIIP serum levels were significantly higher than those of controls and cirrhotic patients (P less than 0.001 and P less than 0.01 respectively) but an analysis of individual values showed an important overlap between PLC and cirrhosis. No correlation was found between serum PIIIP levels and tumour histology, presence or absence of cirrhosis, Child status, possible aetiology of the disease, indices of hepatocellular inflammation, cholestasis and synthesis, or tumour markers. On the contrary, serum PIIIP levels correlated with tumour gross pattern (z = 3, P less than 0.001) and, inversely, with survival (r = 0.659, P less than 0.01), patients with serum PIIIP over 25 ng/mL showing a significantly worse prognosis. These data confirm that hepatic fibroplasia plays an important, but not yet fully understood, role in the course of PLC. From the clinical point of view, PIIIP determination does not add to the differential diagnosis between PLC and cirrhosis but helps to identify patients with larger liver replacements and worse prognoses.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Cirrose Hepática/sangue , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Radioimunoensaio
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