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1.
Edumecentro ; 13(4): 274-287, 2021.
Artigo em Espanhol | LILACS | ID: biblio-1345962

RESUMO

RESUMEN Introducción: la enfermedad por SARS-Cov-2 refuerza la importancia del uso de las nuevas tecnologías de la información y las comunicaciones en función del desarrollo e implementación de sistemas de inteligencia artificial que favorecen el diagnóstico. Objetivo: describir la posibilidad del uso de la inteligencia artificial como una herramienta en la imagenología para los pacientes positivos a la COVID-19. Métodos: se realizó una revisión de fuentes bibliográficas en Infomed, SciELO, PubMed y Google Académico, comprendidas en los años 2015 al 2020 con el uso de palabras claves: coronavirus, COVID-19, neumonía, radiografía e inteligencia artificial. Se seleccionaron 28 documentos por su pertinencia en el estudio. Desarrollo: la creación de sistemas de inteligencia artificial que ayuden al diagnóstico médico requiere un enfoque interprofesional de la ciencia y constituye una de las líneas de trabajo en Cuba durante la pandemia. Una condición indispensable para la introducción de la inteligencia artificial en el diagnóstico radiológico es la capacitación que deben recibir los médicos para interactuar con ella, a través de un proceso formativo que incluya una evaluación y explicación de la calidad de los datos asociada tanto al aprendizaje como a las nuevas predicciones. Conclusiones: la utilización de inteligencia artificial mejorará el rendimiento del radiólogo para distinguir la COVID-19; la integración de estas tecnologías en el flujo de trabajo clínico de rutina puede ayudar a los radiólogos a diagnosticar con precisión.


ABSTRACT Introduction: SARS-Cov-2 disease reinforces the importance of the use of new information and communication technologies based on the development and implementation of artificial intelligence systems that favor diagnosis. Objective: to describe the possibility of using artificial intelligence as a tool in imaging for COVID-19 positive patients. Methods: a review of bibliographic sources was carried out in Infomed, SciELO, PubMed and Google Scholar, from 2015 to 2020 with the use of keywords: coronavirus, COVID-19, pneumonia, radiography and artificial intelligence. 28 documents were selected for their relevance in the study. Development: the creation of artificial intelligence systems that help medical diagnosis requires an interprofessional approach to science and constitutes one of the lines of work in Cuba during the pandemic. An essential condition for the introduction of artificial intelligence in radiological diagnosis is the training that doctors must receive to interact with it, through a training process that includes an evaluation and explanation of the quality of the data associated with both learning and to new predictions. Conclusions: the use of artificial intelligence will improve the radiologist's performance to distinguish COVID-19; integrating these technologies into routine clinical workflow can help radiologists diagnose accurately.


Assuntos
Radiologia , Inteligência Artificial , Infecções por Coronavirus , Imageamento Tridimensional
2.
Rev. cuba. med. mil ; 50(3): e1381, 2021. tab, graf
Artigo em Espanhol | CUMED, LILACS | ID: biblio-1357313

RESUMO

Introducción: Desde el surgimiento de los primeros casos en la pandemia de la COVID-19, se ha desarrollado una carrera vertiginosa en crear un espacio de investigación para el diagnóstico, tratamiento y control de la enfermedad. Objetivo: Describir las características clínicas y radiológicas de los pacientes con la COVID-19. Métodos: Se realizó un estudio descriptivo, en el período comprendido de marzo a octubre del año 2020, se estudiaron 404 pacientes de todas las edades, ingresados, con diagnóstico confirmado con PCR en tiempo real. Las variables utilizadas fueron: edad, sexo, síntomas y radiografía del tórax. Resultados: El 54,5 por ciento de los pacientes fueron del sexo femenino y entre ellos asintomáticos el 55,9 por ciento; el 36,9 por ciento tenía entre 40 a 59 años de edad, en los menores de 20 años, el 64,9 por ciento no presentó síntomas de la enfermedad al ingreso. Estuvieron asintomáticos el 53,5 por ciento; el 76,6 por ciento de las radiografías positivas correspondieron a los sintomáticos, la tos fue el síntoma más frecuente. La mayor positividad en la radiografía del tórax se encontró en los pacientes mayores de 60 años, se observó como patrón más frecuente, la opacidad en velo, de distribución periférica. Conclusiones: Predominan los pacientes asintomáticos, la positividad de las radiografías es mayor en los ancianos(AU)


Introduction: Since the emergence of the first cases of COVID-19 pandemic, a dizzying race has developed in creating a research space for the diagnosis, treatment and control of the disease. Objective: To describe the clinical and radiological characteristics of patients with COVID-19. Methods: A descriptive study was carried out, in the period from March to October 2020, 404 patients of all ages, admitted, with confirmed diagnosis with real-time PCR, were studied. The variables used were: age, sex, symptoms and chest X-ray. Results: 54.5 percent of the patients were female and 55,9 percent of them were asymptomatic, 36,9 percent were between 40 and 59 years old, in those under 20 years 64,9 percent were not. They presented symptoms of the disease upon admission 53,5 percent were asymptomatic, 76,6 percent of the positive radiographs corresponded to the symptomatic ones, coughing was the most frequent symptom. The greatest positivity in the chest X-ray was found in patients older than 60 years, the most frequent pattern was the opacity in the peripheral distribution veil. Conclusions: Asymptomatic patients predominate, the positivity of radiographs is higher in the elderly(AU)


Assuntos
Humanos , Reação em Cadeia da Polimerase , Grupos Raciais , Reação em Cadeia da Polimerase em Tempo Real , COVID-19 , Radiografia Torácica/métodos , Epidemiologia Descritiva
3.
J Appl Toxicol ; 36(11): 1516-25, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27062070

RESUMO

Smallanthus macroscyphus is an herb native to South America whose leaves are a source of antidiabetic compounds, although complete information about their safe use is not available yet. This study was developed to evaluate the toxicity profile of both 10% decoction and the sesquiterpene lactone polymatin A from S. macroscyphus leaves through in vitro cytotoxicity assays and in vivo subchronic oral toxicity. Cell viability of Hep-G2, COS1, CHO-K1 and Vero cell lines decreased in a concentration-dependent manner when cells were incubated with 0.4-200 µg ml(-1) of dry extract or 0.12-60 µg ml(-1) of polymatin A. In subchronic studies, decoction was orally administered to Wistar rats for 90 days at daily doses of 70, 140 and 280 mg kg(-1) of dry extract, whereas polymatin A was administered in the same way at doses of 7, 14 and 28 mg kg(-1) . No toxicity signs or deaths were observed. There were no changes in the behavior, body or organ weights, hematological, biochemical or urine parameters of the rats. No histopathological lesions were observed in the examined organs. The results indicate that the 10% decoction and polymatin A from S. macroscyphus leaves may be considered as non-toxic substances at a wide range of doses, including the effective hypoglycemic dose. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Asteraceae/química , Hipoglicemiantes/toxicidade , Lactonas/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta/química , Sesquiterpenos/toxicidade , Administração Oral , Animais , Asteraceae/crescimento & desenvolvimento , Células CHO , Células COS , Chlorocebus aethiops , Cricetulus , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Hipoglicemiantes/isolamento & purificação , Lactonas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/crescimento & desenvolvimento , Ratos Wistar , Sesquiterpenos/isolamento & purificação , Testes de Toxicidade Subcrônica , Células Vero
4.
J Phys Condens Matter ; 28(9): 094014, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26870908

RESUMO

The ability to selectively chemically functionalize silicon nitride (Si3N4) or silicon dioxide (SiO2) surfaces after cleaning would open interesting technological applications. In order to achieve this goal, the chemical composition of surfaces needs to be carefully characterized so that target chemical reactions can proceed on only one surface at a time. While wet-chemically cleaned silicon dioxide surfaces have been shown to be terminated with surficial Si-OH sites, chemical composition of the HF-etched silicon nitride surfaces is more controversial. In this work, we removed the native oxide under various aqueous HF-etching conditions and studied the chemical nature of the resulting Si3N4 surfaces using infrared absorption spectroscopy (IRAS), x-ray photoelectron spectroscopy (XPS), low energy ion scattering (LEIS), and contact angle measurements. We find that HF-etched silicon nitride surfaces are terminated by surficial Si-F and Si-OH bonds, with slightly subsurface Si-OH, Si-O-Si, and Si-NH2 groups. The concentration of surficial Si-F sites is not dependent on HF concentration, but the distribution of oxygen and Si-NH2 displays a weak dependence. The Si-OH groups of the etched nitride surface are shown to react in a similar manner to the Si-OH sites on SiO2, and therefore no selectivity was found. Chemical selectivity was, however, demonstrated by first reacting the -NH2 groups on the etched nitride surface with aldehyde molecules, which do not react with the Si-OH sites on a SiO2 surface, and then using trichloro-organosilanes for selective reaction only on the SiO2 surface (no reactivity on the aldehyde-terminated Si3N4 surface).

5.
ACS Appl Mater Interfaces ; 6(10): 7340-5, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24750024

RESUMO

The interfacial chemistry of thin (1 nm) silicon (Si) interfacial passivation layers (IPLs) deposited on acid-etched and native oxide InP(100) samples prior to atomic layer deposition (ALD) is investigated. The phosphorus oxides are scavenged completely from the acid-etched samples but not completely from the native oxide samples. Aluminum silicate and hafnium silicate are possibly generated upon ALD and following annealing. The thermal stability of a high-k/Si/InP (acid-etched) stack are also studied by in situ annealing to 400 and 500 °C under ultrahigh vacuum, and the aluminum oxide/Si/InP stack is the most thermally stable. An indium out-diffusion to the sample surface is observed through the Si IPL and the high-k dielectric, which may form volatile species and evaporate from the sample surface.

6.
Chem Biol Interact ; 209: 35-47, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24309157

RESUMO

The aim of the present study was to analyze the in vivo hypoglycaemic effects of both decoction of Smallanthus macroscyphus leaves and pure crystalline polymatin A isolated from its leaves. Phytochemical analysis of the leaf decoction showed that its major constituents were caffeic, chlorogenic and three dicaffeoilquinic acids, together with the sesquiterpene lactone polymatin A. Oral glucose tolerance test in normal rats was performed to evaluate the hypoglycemic activity and to choose the minimum effective dose of the decoction and polymatin A. They have effective hypoglycemic activity at the minimum dose of 140 mg dry extract and 14 mg crystalline powder/kg body weight, respectively, and were selected for the following experiments. Oral administration of a single-dose of decoction produced a moderate lowering effect in fasting glycemia of normal rats, whereas polymatin A had no significant effect. We also assessed the effect of a single-dose on post-prandial blood glucose, resulting in an inhibition of the hyperglycemic peak after sucrose overload. Daily administration of decoction or polymatin A for 4 weeks produced an effective glycemic control in diabetic animals, with a decrease in urinary glucose excretion and a significant reduction in the HbA1c levels. Although there were no significant increases in plasma insulin levels, both treatments improved the fasting blood glucose/insulin ratio. In vivo acute toxicity studies were performed in adult Wistar rats. There were no deaths or signs of toxicity observed after oral administration of decoction or polymatin A at any dose level up to the highest dose tested (14.0 and 2.8 g/kg, respectively). The results presented here strongly support the notion that S. macroscyphus represents a new source of antidiabetic compounds that could help to manage diabetes more efficiently and safely.


Assuntos
Asteraceae/química , Glicemia/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Lactonas/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Administração Oral , Animais , Glicemia/análise , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Experimental/tratamento farmacológico , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Hipoglicemiantes/química , Lactonas/química , Masculino , Extratos Vegetais/química , Folhas de Planta/química , Ratos , Ratos Wistar , Sesquiterpenos/química
7.
J Ethnopharmacol ; 144(2): 362-70, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23000115

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of Smallanthus sonchifolius (Poepp. & Endl.) H. Robinson (yacon) have been used since pre-Columbian times in the Andean region to prepare medicinal herbal tea with beneficial health properties. However, there are still disagreements about the safe use. This work was carried out to evaluate the toxicity profile of both, 10% decoction of yacon leaves and their major active lactone, enhydrin. MATERIALS AND METHODS: In vitro cytotoxicity assays were performed with Hep-G2, COS1, CHO-K1 and Vero cell lines using a test of metabolic competence based upon assessment of mitochondrial performance. In vivo toxicity study was performed in adult Wistar rats. In the acute oral toxicity each group of rats was orally given a single dose of 10% decoction or enhydrin. General condition, behavior and mortality were recorded for up to 14 days post treatment. In subchronic toxicity studies, both products were given orally for 90 days to rats. Body weight and food intakes were observed weekly. Hematological, clinical chemistry parameters and organ weight were determined in all animals at the end of the experimental period. RESULTS: Cell viability decreased in a concentration dependent fashion when cells were incubated with 2-200 µg of 10% decoction and 0.015-7.5 µg of enhydrin. In acute study in rats, there were no deaths or signs of toxicity observed after oral administration of single doses of 10% decoction or enhydrin at any dose level up to the highest dose tested (14.0 g/kg and 0.32 g/kg, respectively). In subchronic studies in rats, both products administered orally for 90 days at daily doses of 0.07, 0.14 and 0.28 g 10% decoction/kg and 0.4, 0.8 and 8.0 mg enhydrin/kg, did not caused haematological, biochemical and histological alterations. CONCLUSIONS: The results presented in this paper lead us to the conclusion that the use of 10% decoction and enhydrin is safe in rat at doses in which it is demonstrated the hypoglycaemic effect.


Assuntos
Asteraceae , Hipoglicemiantes/toxicidade , Extratos Vegetais/toxicidade , Sesquiterpenos/toxicidade , Animais , Células CHO , Células COS , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cricetinae , Cricetulus , Feminino , Células Hep G2 , Humanos , Hipoglicemiantes/isolamento & purificação , Lactonas/isolamento & purificação , Lactonas/toxicidade , Masculino , Folhas de Planta , Ratos Wistar , Sesquiterpenos/isolamento & purificação , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica , Células Vero
8.
Food Chem Toxicol ; 50(5): 1704-15, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22406203

RESUMO

Nephropathy is the most common cause of morbidity and mortality in diabetic patients. Prevention of this complication has a major relevance. Smallanthus sonchifolius (yacon) leaves have been shown to ameliorate hyperglycemia in streptozotocin-induced diabetic rats. We examined the beneficial effects of yacon leaves decoction on diabetic nephropathy and explored the possible underlying action mechanism. Streptozotocin-diabetic rats were orally administered 10% yacon leaves water decoction (70mg dry extract/kg body weight) once a day for 4weeks. Biochemical parameters in blood and urine were analyzed and immunohistochemistry staining, western immunoblotting and qRT-PCR were assessed. Yacon decoction significantly decreased high blood glucose level in diabetic rats and improved insulin production. Diabetic-dependent alterations in urinary albumin excretion, creatinine clearance, kidney hypertrophy and basement membrane thickening were attenuated by yacon decoction. These findings were associated with a marked decrease in TGF-ß1/Smad2/3 signaling. The expression of molecular markers of diabetic nephropathy such as collagen IV, laminin-1, fibronectin and collagen III were also diminished in the yacon-treated group compared to control diabetic group. These results suggest that yacon leaves decoction is a protective agent against renal damage in diabetic nephropathy, whose action can be mediated by TGF-ß/Smads signals.


Assuntos
Asteraceae/química , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/prevenção & controle , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Actinas/metabolismo , Animais , Western Blotting , Colágeno Tipo III/metabolismo , Colágeno Tipo IV/metabolismo , Nefropatias Diabéticas/fisiopatologia , Fibronectinas/metabolismo , Imuno-Histoquímica , Rim/metabolismo , Rim/fisiopatologia , Laminina/metabolismo , Masculino , Ratos , Ratos Wistar , Estreptozocina
9.
Chem Biol Interact ; 185(2): 143-52, 2010 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-20211156

RESUMO

The aim of the present study was to determine the in vivo hypoglycemic activity of five organic extracts and enhydrin obtained from yacon leaves. The main constituents of the most active fraction were identified. Five organic extracts and pure crystalline enhydrin were administered to normoglycemic, transiently hyperglycemic and streptozotocin (STZ)-diabetic rats. The fasting and post-prandial blood glucose, and serum insulin levels were estimated and an oral glucose tolerance test (OGTT) was performed for the evaluation of hypoglycemic activity and dose optimization of each extract. We found that the methanol, butanol and chloroform extracts showed effective hypoglycemic activity at minimum doses of 50, 10 and 20mg/kg body weight, respectively, and were selected for further experiments. Oral administration of a single-dose of each extract produced a slight lowering effect in the fasting blood glucose level of normal healthy rats, whereas each extract tempered significantly the hyperglycemic peak after food ingestion. Daily administration of each extract for 8 weeks produced an effective glycemic control in diabetic animals with an increase in the plasma insulin level. Phytochemical analysis of the most active fraction, the butanol extract, showed that caffeic, chlorogenic and three dicaffeoilquinic acids were significant components. Additionally, enhydrin, the major sesquiterpene lactone of yacon leaves, was also effective to reduce post-prandial glucose and useful in the treatment of diabetic animals (minimum dose: 0.8mg/kg body weight). The results presented here strongly support the notion that the phenolic compounds above as well as enhydrin are important hypoglycemic principles of yacon leaves that could ameliorate the diabetic state.


Assuntos
Asteraceae/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Ácido Clorogênico/química , Ácido Clorogênico/classificação , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Teste de Tolerância a Glucose , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Insulina/sangue , Masculino , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico , Solventes/química , Estreptozocina/toxicidade , Fatores de Tempo
10.
Clin Nutr ; 28(2): 182-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19254816

RESUMO

BACKGROUND & AIMS: Syrup obtained from yacon roots could be well positioned as a nutraceutical product due to its high fructooligosaccharides content. We examined the beneficial effects and tolerance of yacon syrup on human health. METHODS: Obese and slightly dyslipidemic pre-menopausal women were studied over a 120-day period in a double-blind placebo-controlled experiment. We used two doses of yacon syrup, 0.29 g and 0.14 g fructooligosaccharides/kg/day. At the start and end of the study, anthropometric measurements, blood glucose, calcium, lipid and insulin concentrations and Homeostasis Model Assessment index were determined. RESULTS: The recommended daily consumption of yacon syrup with no undesirable gastrointestinal effects is 0.14 g fructooligosaccharides/kg. Daily intake of yacon syrup produced a significant decrease in body weight, waist circumference and body mass index. Additionally, decrease in fasting serum insulin and Homeostasis Model Assessment index was observed. The consumption of yacon syrup increased defecation frequency and satiety sensation. Fasting glucose and serum lipids were not affected by syrup treatment and the only positive effect was found in serum LDL-cholesterol levels. CONCLUSIONS: Yacon syrup is a good source of fructooligosaccharides and its long-term consumption produced beneficial health effects on obese pre-menopausal women with insulin resistance.


Assuntos
Resistência à Insulina , Obesidade/dietoterapia , Extratos Vegetais/administração & dosagem , Preparações de Plantas/farmacologia , Adulto , Antropometria , Glicemia/efeitos dos fármacos , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Cálcio/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dislipidemias/dietoterapia , Feminino , Humanos , Insulina/sangue , Lipídeos/sangue , Pessoa de Meia-Idade , Resposta de Saciedade/efeitos dos fármacos
11.
Food Chem Toxicol ; 43(11): 1657-65, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15979774

RESUMO

Yacon roots are a rich source of fructooligosaccharides (FOS) and have a long use tradition as food in the Andean region. However, there are no published reports regarding their toxicology and use safety. The aim of this study was to analyze the effects of subchronic (4-months) oral consumption of dried yacon root flour as a diet supplement using normal Wistar rats. Two daily intake levels were used, equivalent to 340 mg and 6800 mgFOS/body weight, respectively. Yacon administered as a diet supplement was well tolerated and did not produce any negative response, toxicity or adverse nutritional effect at both intake levels used. Yacon root consumption showed no hypoglycemic activity in normal rats and resulted in significantly reduced post-prandial serum triacylglycerol levels in both doses assayed. Conversely, serum cholesterol reduction was not statistically significant. Cecal hypertrophy was observed in rats fed only the high dose. Our results indicating lack of toxicity and a certain beneficial metabolic activity in normal rats warrant further experiments with normal subjects and patients suffering metabolic disorders. They should also be considered when establishing the regulatory framework of this natural product by national health authorities and international trade agencies.


Assuntos
Asteraceae/toxicidade , Suplementos Nutricionais , Animais , Asteraceae/química , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Carboidratos da Dieta/análise , Suplementos Nutricionais/efeitos adversos , Ingestão de Alimentos , Feminino , Teste de Tolerância a Glucose , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Masculino , Oligossacarídeos/análise , Raízes de Plantas/química , Raízes de Plantas/toxicidade , Ratos , Ratos Wistar , Sobrevida , Triglicerídeos/análise , Urina/química
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