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1.
Sensors (Basel) ; 19(22)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766187

RESUMO

Gas multisensor devices offer an effective approach to monitor air pollution, which has become a pandemic in many cities, especially because of transport emissions. To be reliable, properly trained models need to be developed that combine output from sensors with weather data; however, many factors can affect the accuracy of the models. The main objective of this study was to explore the impact of several input variables in training different air quality indexes using fuzzy logic combined with two metaheuristic optimizations: simulated annealing (SA) and particle swarm optimization (PSO). In this work, the concentrations of NO2 and CO were predicted using five resistivities from multisensor devices and three weather variables (temperature, relative humidity, and absolute humidity). In order to validate the results, several measures were calculated, including the correlation coefficient and the mean absolute error. Overall, PSO was found to perform the best. Finally, input resistivities of NO2 and nonmetanic hydrocarbons (NMHC) were found to be the most sensitive to predict concentrations of NO2 and CO.

2.
Materials (Basel) ; 12(10)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121948

RESUMO

This study aims to investigate the prediction of critical buckling load of steel columns using two hybrid Artificial Intelligence (AI) models such as Adaptive Neuro-Fuzzy Inference System optimized by Genetic Algorithm (ANFIS-GA) and Adaptive Neuro-Fuzzy Inference System optimized by Particle Swarm Optimization (ANFIS-PSO). For this purpose, a total number of 57 experimental buckling tests of novel high strength steel Y-section columns were collected from the available literature to generate the dataset for training and validating the two proposed AI models. Quality assessment criteria such as coefficient of determination (R2), Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE) were used to validate and evaluate the performance of the prediction models. Results showed that both ANFIS-GA and ANFIS-PSO had a strong ability in predicting the buckling load of steel columns, but ANFIS-PSO (R2 = 0.929, RMSE = 60.522 and MAE = 44.044) was slightly better than ANFIS-GA (R2 = 0.916, RMSE = 65.371 and MAE = 48.588). The two models were also robust even with the presence of input variability, as investigated via Monte Carlo simulations. This study showed that the hybrid AI techniques could help constructing an efficient numerical tool for buckling analysis.

3.
Rev Med Virol ; 28(3): e1977, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29664167

RESUMO

Middle East respiratory syndrome (MERS) is a respiratory disease caused by MERS coronavirus. Because of lack of vaccination, various studies investigated the therapeutic efficacy of antiviral drugs and supportive remedies. A systematic literature search from 10 databases was conducted and screened for relevant articles. Studies reporting information about the treatment of MERS coronavirus infection were extracted and analyzed. Despite receiving treatment with ribavirin plus IFN, the case fatality rate was as high as 71% in the IFN-treatment group and exactly the same in patients who received supportive treatment only. Having chronic renal disease, diabetes mellitus and hypertension increased the risk of mortality (P < .05), and chronic renal disease is the best parameter to predict the mortality. The mean of survival days from onset of illness to death was 46.6 (95% CI, 30.5-62.6) for the IFN group compared with 18.8 (95% CI, 10.3-27.4) for the supportive-only group (P = .001). Delay in starting treatment, older age group, and preexisting comorbidities are associated with worse outcomes. In conclusion, there is no difference between IFN treatment and supportive treatment for MERS patients in terms of mortality. However, ribavirin and IFN combination might have efficacious effects with timely administration and monitoring of adverse events. Large-scale prospective randomized studies are required to assess the role of antiviral drugs for the treatment of this high mortality infection.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio , Antivirais/farmacologia , Infecções por Coronavirus/mortalidade , Feminino , Humanos , Interferons/farmacologia , Interferons/uso terapêutico , Masculino , Fatores de Risco , Resultado do Tratamento
4.
J Cereb Blood Flow Metab ; 37(6): 2112-2124, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27481936

RESUMO

Brain lactate concentration is higher during wakefulness than in sleep. However, it is unknown why arousal is linked to an increase in brain lactate and why lactate declines within minutes of sleep. Here, we show that the glymphatic system is responsible for state-dependent changes in brain lactate concentration. Suppression of glymphatic function via acetazolamide treatment, cisterna magna puncture, aquaporin 4 deletion, or changes in body position reduced the decline in brain lactate normally observed when awake mice transition into sleep or anesthesia. Concurrently, the same manipulations diminished accumulation of lactate in cervical, but not in inguinal lymph nodes when mice were anesthetized. Thus, our study suggests that brain lactate is an excellent biomarker of the sleep-wake cycle and increases further during sleep deprivation, because brain lactate is inversely correlated with glymphatic-lymphatic clearance. This analysis provides fundamental new insight into brain energy metabolism by demonstrating that glucose that is not fully oxidized can be exported as lactate via glymphatic-lymphatic fluid transport.


Assuntos
Encéfalo/metabolismo , Líquido Cefalorraquidiano/metabolismo , Ácido Láctico/metabolismo , Sistema Linfático/metabolismo , Sono/fisiologia , Vigília/fisiologia , Animais , Aquaporina 4/genética , Eletroencefalografia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microdiálise
5.
Diabetes ; 64(1): 104-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25048197

RESUMO

Chromogranin A knockout (Chga-KO) mice exhibit enhanced insulin sensitivity despite obesity. Here, we probed the role of the chromogranin A-derived peptide pancreastatin (PST: CHGA(273-301)) by investigating the effect of diet-induced obesity (DIO) on insulin sensitivity of these mice. We found that on a high-fat diet (HFD), Chga-KO mice (KO-DIO) remain more insulin sensitive than wild-type DIO (WT-DIO) mice. Concomitant with this phenotype is enhanced Akt and AMPK signaling in muscle and white adipose tissue (WAT) as well as increased FoxO1 phosphorylation and expression of mature Srebp-1c in liver and downregulation of the hepatic gluconeogenic genes, Pepck and G6pase. KO-DIO mice also exhibited downregulation of cytokines and proinflammatory genes and upregulation of anti-inflammatory genes in WAT, and peritoneal macrophages from KO mice displayed similarly reduced proinflammatory gene expression. The insulin-sensitive, anti-inflammatory phenotype of KO-DIO mice is masked by supplementing PST. Conversely, a PST variant peptide PSTv1 (PST-NΔ3: CHGA(276-301)), lacking PST activity, simulated the KO phenotype by sensitizing WT-DIO mice to insulin. In summary, the reduced inflammation due to PST deficiency prevented the development of insulin resistance in KO-DIO mice. Thus, obesity manifests insulin resistance only in the presence of PST, and in its absence obesity is dissociated from insulin resistance.


Assuntos
Cromogranina A/imunologia , Obesidade/imunologia , Obesidade/metabolismo , Hormônios Pancreáticos/farmacologia , Paniculite/imunologia , Transdução de Sinais/imunologia , Tecido Adiposo/imunologia , Tecido Adiposo/metabolismo , Animais , Células Cultivadas , Quimiotaxia/imunologia , Cromogranina A/genética , Cromogranina A/metabolismo , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Intolerância à Glucose/tratamento farmacológico , Intolerância à Glucose/imunologia , Intolerância à Glucose/metabolismo , Resistência à Insulina/imunologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/tratamento farmacológico , Hormônios Pancreáticos/imunologia , Hormônios Pancreáticos/metabolismo , Paniculite/tratamento farmacológico , Paniculite/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/imunologia , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
6.
Radiol Clin North Am ; 52(5): 1087-99, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25173660

RESUMO

The development of colorectal cancer screening programs in many countries has led to increasingly large numbers of patients undergoing optical colonoscopy. Although acute complications from screening optical colonoscopy are uncommon, they may occur in up to 5% or more of patients where biopsies or therapeutic procedures are performed. Abdominal radiographs are of value only for the detection of intraperitoneal perforation. There is a wide spectrum of other important associated complications. Such complications are most reliably identified using abdominal and pelvic CT, which also can guide appropriate conservative, interventional, or surgical management.


Assuntos
Colonografia Tomográfica Computadorizada/métodos , Colonoscopia/efeitos adversos , Enteropatias/diagnóstico por imagem , Enteropatias/etiologia , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Peritônio/diagnóstico por imagem , Peritônio/lesões , Baço/diagnóstico por imagem , Baço/lesões
7.
Clin Nucl Med ; 38(9): e367-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23856822

RESUMO

Extraskeletal osteosarcoma (EO) is a rare malignancy and its FDG PET/CT imaging is seldom reported. We present staging and restaging images of a FDG PET/CT imaging in an EO originating from paraspinous musculature. Initial staging FDG PET/CT scan showed increased metabolism of a mass in the right paraspinous region without nodal or distant metastasis. The patient underwent tumor resection and radiation therapy with a pathological diagnosis of EO. Restaging FDG PET/CT imaging demonstrated postsurgical changes without nodal or distant metastasis. This case demonstrates the clinical relevance of FDG PET/CT imaging for staging and restaging EO.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Fluordesoxiglucose F18 , Osteossarcoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Humanos , Masculino , Imagem Multimodal
8.
Int J Radiat Oncol Biol Phys ; 85(5): 1375-82, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23219566

RESUMO

PURPOSE: To extract and study comprehensive spatial-temporal (18)F-labeled fluorodeoxyglucose ([(18)F]FDG) positron emission tomography (PET) features for the prediction of pathologic tumor response to neoadjuvant chemoradiation therapy (CRT) in esophageal cancer. METHODS AND MATERIALS: Twenty patients with esophageal cancer were treated with trimodal therapy (CRT plus surgery) and underwent [(18)F]FDG-PET/CT scans both before (pre-CRT) and after (post-CRT) CRT. The 2 scans were rigidly registered. A tumor volume was semiautomatically delineated using a threshold standardized uptake value (SUV) of ≥2.5, followed by manual editing. Comprehensive features were extracted to characterize SUV intensity distribution, spatial patterns (texture), tumor geometry, and associated changes resulting from CRT. The usefulness of each feature in predicting pathologic tumor response to CRT was evaluated using the area under the receiver operating characteristic curve (AUC) value. RESULTS: The best traditional response measure was decline in maximum SUV (SUVmax; AUC, 0.76). Two new intensity features, decline in mean SUV (SUVmean) and skewness, and 3 texture features (inertia, correlation, and cluster prominence) were found to be significant predictors with AUC values ≥0.76. According to these features, a tumor was more likely to be a responder when the SUVmean decline was larger, when there were relatively fewer voxels with higher SUV values pre-CRT, or when [(18)F]FDG uptake post-CRT was relatively homogeneous. All of the most accurate predictive features were extracted from the entire tumor rather than from the most active part of the tumor. For SUV intensity features and tumor size features, changes were more predictive than pre- or post-CRT assessment alone. CONCLUSION: Spatial-temporal [(18)F]FDG-PET features were found to be useful predictors of pathologic tumor response to neoadjuvant CRT in esophageal cancer.


Assuntos
Quimiorradioterapia Adjuvante/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Fluordesoxiglucose F18 , Terapia Neoadjuvante/métodos , Compostos Radiofarmacêuticos , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Cisplatino/administração & dosagem , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Fluordesoxiglucose F18/farmacocinética , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Estudos Retrospectivos , Análise Espaço-Temporal , Tomografia Computadorizada por Raios X
9.
Clin Nucl Med ; 37(5): 492-4, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22475902

RESUMO

Peritoneal mesothelioma is a rare and aggressive tumor. Early diagnosis of the disease is difficult, delaying effective treatment. We report a case of recurrent, biphasic, diffuse, malignant peritoneal mesothelioma. Initial abdominal computed tomography showed abnormal but nonspecific findings suggestive of an ovarian malignancy, with a negative endoscopy and laboratory studies. An abdominal exploratory laparotomy found widespread malignancy within the peritoneum with a pathological diagnosis of peritoneal mesothelioma. A PET/CT imaging showed diffusely increased metabolic activity throughout the peritoneum, with no evidence of thoracic or pleural involvement. This case demonstrates the PET/CT findings seen with malignant recurrent peritoneal mesothelioma.


Assuntos
Fluordesoxiglucose F18 , Mesotelioma/diagnóstico por imagem , Imagem Multimodal , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias Peritoneais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Feminino , Humanos , Pessoa de Meia-Idade
10.
PET Clin ; 6(4): 441-52, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27156879

RESUMO

Recent advances in multidetector computed tomography (CT), with submillimeter spatial resolution, improved temporal resolution, and electrocardiographic gating, make it possible to image and accurately characterize the coronary arteries. Cardiac CT offers the ability to noninvasively assess cardiovascular anatomy, including coronary arteries, bypass grafts and stents, myocardium, pericardium, and cardiac function. A growing body of literature supports the prognostic value of coronary CT angiography. This article provides an overview of clinical applications, scanning protocols, limitations, and future developments of cardiac CT.

11.
Radiol Clin North Am ; 48(4): 757-70, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20705171

RESUMO

Although conventional coronary angiography is used to evaluate the patency of coronary artery bypass grafts, it is invasive and has associated risks. The evolution of the multidetector CT (MDCT) has enabled accurate, noninvasive visualization of graft patency. This article identifies and describes typical MDCT findings in bypass grafts and native coronary arteries.


Assuntos
Doenças Cardiovasculares/cirurgia , Ponte de Artéria Coronária/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Stents , Tomografia Computadorizada por Raios X/métodos , Artefatos , Doenças Cardiovasculares/diagnóstico por imagem , Meios de Contraste , Angiografia Coronária , Eletrocardiografia , Humanos , Grau de Desobstrução Vascular
12.
J Comput Assist Tomogr ; 34(3): 385-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20498541

RESUMO

RATIONALE AND OBJECTIVES: The purpose of the study was to quantitatively assess the percentage of total lung parenchyma visualized on cardiac computed tomographic angiography (CTA) using standard and tight-coned fields of view (FOVs). MATERIALS AND METHODS: The authors evaluated lung volumes in 43 electrocardiogram-gated cardiac CTAs performed as part of triple rule-out/chest pain protocol CTAs over a 9-month period. Using a commercially available software package, a quantitative tissue differentiation analysis was performed using a threshold of -750 Hounsfield units to segment air in the lungs. Using each triple rule-out data set as a starting point, measurements of lung volume were performed with 2 cardiac CTA FOV scenarios, obtained by excluding the periphery of the triple rule-out volume: (1) standard cardiac CTA FOV typically used and recommended by the manufacturer and (2) tight cardiac CTA FOV maximally coned to the heart. For each scenario, the volume of the lung within the restricted FOV was compared with the overall volume of the lungs derived from the triple rule-out study, expressed as a percentage. RESULTS: On the standard cardiac CTA FOV typically used at our institution, a mean of 58% of the lung parenchyma is included with wide variability (range, 26%-86%). On the severely limited FOV, a mean of 14% (range, 7.5%-22%) of the lung parenchyma is included. CONCLUSIONS: The percentage of lung parenchyma included in a standard FOV is considerable, although this can be mitigated by using a tight FOV, with potential exclusion of part of the cardiac anatomy. Interpreters of cardiac CTA images should have adequate training and skill in evaluating structures outside the heart.


Assuntos
Angiografia Coronária/métodos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
J Immunol ; 171(6): 3148-53, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12960342

RESUMO

In some parts of Africa, 50% of deaths attributed to malaria occur in infants less than 8 mo. Thus, immunization against malaria may have to begin in the neonatal period, when neonates have maternally acquired Abs against malaria parasite proteins. Many malaria vaccines in development rely upon CD8 cells as immune effectors. Some studies indicate that neonates do not mount optimal CD8 cell responses. We report that BALB/c mice first immunized as neonates (7 days) with a Plasmodium yoelii circumsporozoite protein (PyCSP) DNA vaccine mixed with a plasmid expressing murine GM-CSF (DG) and boosted at 28 days with poxvirus expressing PyCSP were protected (93%) as well as mice immunized entirely as adults (70%). Protection was dependent on CD8 cells, and mice had excellent anti-PyCSP IFN-gamma and cytotoxic T lymphocyte responses. Mice born of mothers previously exposed to P. yoelii parasites or immunized with the vaccine were protected and had excellent T cell responses. These data support assessment of this immunization strategy in neonates/young infants in areas in which malaria exacts its greatest toll.


Assuntos
Animais Recém-Nascidos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade Materno-Adquirida , Ativação Linfocitária , Vacinas Antimaláricas/imunologia , Malária/prevenção & controle , Poxviridae/imunologia , Vacinas de DNA/administração & dosagem , Animais , Anticorpos Antiprotozoários/biossíntese , Anticorpos Antiprotozoários/sangue , Feminino , Imunidade Materno-Adquirida/genética , Esquemas de Imunização , Imunização Secundária/métodos , Injeções Intramusculares , Cinética , Ativação Linfocitária/genética , Malária/imunologia , Malária/parasitologia , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/genética , Masculino , Troca Materno-Fetal/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Poxviridae/genética , Gravidez , Esporozoítos/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia
14.
Infect Immun ; 70(7): 3493-9, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12065488

RESUMO

The persistence of immunity to malaria induced in mice by a heterologous DNA priming and poxvirus boosting regimen was characterized. Mice were immunized by priming with DNA vaccine plasmids encoding the Plasmodium yoelii circumsporozoite protein (PyCSP) and murine granulocyte-macrophage colony-stimulating factor and boosting with recombinant vaccinia encoding PyCSP. BALB/c mice immunized with either high-dose (100 microg of p PyCSP plus 30 microg of pGM-CSF) or low-dose (1 microg of p PyCSP plus 1 microg of pGM-CSF DNA) priming were protected against challenge with 50 P. yoelii sporozoites. Protection 2 weeks after immunization was 70 to 100%, persisted at this level for at least 20 weeks, and declined to 30 to 40% by 28 weeks. Eight of eight mice protected at 20 weeks were still protected when rechallenged at 40 weeks. The antigen (Ag)-specific effector CD8(+)-T-cell population present 2 weeks after boosting had ex vivo Ag-specific cytolytic activity, expressed both gamma interferon (IFN-gamma) and tumor necrosis factor alpha, and constituted 12 to 20% of splenic CD8(+) T cells. In contrast, the memory CD8(+)-Ag-specific-cell population at 28 weeks lacked cytolytic activity and constituted only 6% of splenic CD8(+) T cells, but at the single-cell level it produced significantly higher levels of IFN-gamma than the effectors. High levels of Ag- or parasite-specific antibodies present 2 weeks after boosting had declined three- to sevenfold by 28 weeks. Low-dose priming was similarly immunogenic and as protective as high-dose priming against a 50-, but not a 250-, sporozoite challenge. These results demonstrate that a heterologous priming and boosting vaccination can provide lasting protection against malaria in this model system.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , DNA de Protozoário/imunologia , Vacinas Antimaláricas/imunologia , Malária/prevenção & controle , Plasmodium yoelii/imunologia , Proteínas de Protozoários/imunologia , Vacinas de DNA/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/genética , Feminino , Vetores Genéticos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Imunização Secundária , Memória Imunológica/imunologia , Malária/imunologia , Vacinas Antimaláricas/genética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Plasmodium yoelii/genética , Proteínas de Protozoários/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia , Fatores de Tempo , Vacinas de DNA/genética , Vaccinia virus
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