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1.
Heliyon ; 9(12): e22445, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076038

RESUMO

This study evaluated the ultrasound-assisted extraction of phenolic compounds from Guadua angustifolia leaves, along with their optimization using response surface methodology. The effects of two sonication process conditions were determined using a central composite experimental design, with three levels (low, medium, and high) evaluated for time (10, 20, and 30 min) and temperature (20 °C, 35 °C, and 50 °C). A total of 12 experiments with four replicates were conducted at the central point, with the total phenol and flavonoid contents determined using the Folin-Ciocalteu colorimetric method and complexation with AlCl3, respectively. The optimized extract was analyzed using ultra-performance liquid chromatography (UPLC), and the antioxidant capacity of the optimized extract was determined by DPPH• (2,2-Diphenyl-1-Picrylhydrazyl) and ABTS•+ (2,2'-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) assays. Extraction at 50 °C for 20 min was found to favor the extraction of phenol and total flavonoids. The experimental validation of the total phenol and flavonoid content produced values of 7.39 mg gallic acid equivalents per gram of dry matter and 1.55 mg quercetin equivalents per gram of dry matter, respectively. These values suggest that the extraction process is reproducible, with a relative standard deviation of 22.9 % and 14.1 %, respectively. The chromatographic profile showed that optimization favored the visualization of phenolic compounds compared to the non-optimized extract. The optimized extract had higher antioxidant capacity than the non-optimized extract, with values of 209.23 and 144.76 µmol Trolox per gram extract for the DPPH• and ABTS•+ techniques, respectively. Thus, the conditions evaluated in the ultrasound-assisted extraction were an efficient technique capable of extracting the maximum amount of phenolic compounds with antioxidant activity from the leaves of G. angustifolia, showing its potential application in various industries.

2.
J Clin Med ; 12(18)2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37762822

RESUMO

There is a need of simple, inexpensive, and reliable noninvasive testing to predict coronary artery disease (CAD) in patients with chronic kidney disease (CKD), where the prevalence of cardiovascular (CV) events and death is elevated. We analyzed the association between peripheral artery disease (PAD) and CAD in 201 patients with stage 5 CKD on dialysis using a prospective observational cohort. Diagnosis of PAD by both palpation and USD were significantly correlated. In patients with PAD diagnosed by palpation, CAD was observed in 80%, while in those diagnosed by USD, CAD was present in 79.1%. The absence of a pulse by palpation predicted CAD with a sensitivity of 55% and a specificity of 76%; USD showed a sensitivity of 62% and specificity of 60% to predict CAD. The risk of combined serious CV events and death was significantly higher in subjects with PAD diagnosed by palpation, but not by USD. PAD assessed by palpation also correlated with the occurrence of multivessel CAD and with the probability of coronary intervention. Both methods are moderately useful for predicting CAD, but PAD diagnosis by palpation was a better predictor of combined CV events and death and was also associated with CAD severity and likelihood of intervention.

3.
Entropy (Basel) ; 21(4)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33267144

RESUMO

This paper proposes the q-sigmoid functions, which are variations of the sigmoid expressions and an analysis of their application to the process of enhancing regions of interest in digital images. These new functions are based on the non-extensive Tsallis statistics, arising in the field of statistical mechanics through the use of q-exponential functions. The potential of q-sigmoids for image processing is demonstrated in tasks of region enhancement in ultrasound images which are highly affected by speckle noise. Before demonstrating the results in real images, we study the asymptotic behavior of these functions and the effect of the obtained expressions when processing synthetic images. In both experiments, the q-sigmoids overcame the original sigmoid functions, as well as two other well-known methods for the enhancement of regions of interest: slicing and histogram equalization. These results show that q-sigmoids can be used as a preprocessing step in pipelines including segmentation as demonstrated for the Otsu algorithm and deep learning approaches for further feature extractions and analyses.

4.
Fisioter. mov ; 23(2): 271-281, abr.-jun. 2010.
Artigo em Português | LILACS | ID: lil-566079

RESUMO

OBJETIVO: Fazer uma revisão bibliográfica a respeito dos efeitos dos principais recursos eletrofísicos utilizados na aceleração do metabolismo ósseo e no tratamento da osteoporose. ANTECEDENTES: A Organização Mundial da Saúde (OMS) define a osteoporose como doença esquelética sistêmica caracterizada por diminuição da massa óssea e deterioração microarquitetural do tecido ósseo, com consequente aumento da fragilidade óssea e susceptibilidade à fratura. Vários tratamentos medicamentosos e não medicamentosos vêm sendo desenvolvidos na tentativa de aumentar a massa óssea e prevenir a osteoporose. Dentro desse contexto, os recursos eletrofísicos vêm tendo um papel de destaque, como recursos que apresentam um potencial osteogênico, capazes de estimular a proliferação de osteoblastos e biomodular o metabolismo ósseo. ESTRATÉGIA DE PESQUISA: Foram consultadas as bases de dados: The Cochrane Library, MEDLINE, Embase, LILACS, SciELO, referências dos artigos identificados, e contato com especialisas em laser, entre os anos de 1983 e 2009. CRITÉRIOS DE SELEÇÃO: Foram incluídos estudos experimentais e ensaios clínicos randomizados que avaliaram os efeitos dos recursos eletrofísicos na osteoporose. RECOMPILAÇÃO E ANÁLISE DE DADOS: Dois revisores selecionaram independentemente os estudos, avaliaram sua qualidade metodológica dos estudos e coletaram os dados. RESULTADOS: Todos os recursos eletrofísicos citados neste artigo se mostraram eficazes na estimulação do metabolismo ósseo. No entanto, a grande maioria dos estudos realizados evidenciam esses efeitos através de estudos in vitro e estudos experimentais com cobaias. Cabe ressaltar que trabalhos como esses são raros em seres humanos. Baseado nos achados desta revisão pode ser sugerido que os recursos eletrofísicios como o laser terapêutico, o ultrassom, campos eletromagnéticos e plataformas vibratórias são recursos que tem um potencial osteogênico entretanto mais estudos são necessários para definir os efeitos dos mesmos em humanos, bem como, protocolos mais eficazes de tratamento. CONCLUSÃO: A partir deste levantamento bibliográfico, fica evidente que os recursos eletrofísicos apresentam um grande potencial osteogênico, porém, a maior parte dos estudos é in vitro. São necessários mais estudos in vivo, definindo, assim, melhores parâmetros e doses, para que sejam utilizados no tratamento da osteoporose.


OBJECTIVE: The aim of this article was to provide a literature review regarding the impact of the main eletrophysical resources used on the acceleration of bone metabolism and on the osteoporosis treatment. DEFINITION: The OMS defines osteoporosis as a Sistemic esqueletical disease characterized for diminished bone mass and for deterioration of the bone mass microarchitecture, increasing the bone fragility and susceptibility to fracture. Many drug or non-drug treatments are being developed as an attempt to increase the bone mass, and prevent osteoporosis. Within this context, the eletrophysical resources is having a prominence paper, as a resource which presents a osteogenic potencial, capable of stimulating the proliferation of osteoblasts and biomodulate the bone metabolism. RESEARCH STRATEGIES: The data base consulted were: The Cochrane Library, MEDLINE, Embase, LILACS, SciELO, references of indentified articles and contact with laser's especialists, between 1983 and 2009. SELECTION CRITERIA: Were included experimental study and randomized clinical tests on the effects of eletrophysical resources on osteoporosis. RECOMPILATION AND DATA ANALISIS: Two reviewers independently selected the studies, assessed their methodological quality and collected the data. RESULTS: All the eletrophysical resources quoted on this article were effective in stimulation of bone metabolism. However, most of the studies show these effects through in vitro studies and experimental studies with animals. It is important to say that experiments like these are rare in human beings. Based on the findings of this review, it may be suggested that the eletrophysical resources like lasertherapy, ultra-sound, electromagnetic fields and vibration are resources that has osteogenic potencial, but more studies are needed to define the effects of it in humans, as well as more effective treatment protocols. CONCLUSION: With this literature review it is clear that eletrophysical resources have high osteogenic potential, but most of the studies are in vitro. It is needed more studies in vivo, defining therefore, better parameters and doses to be used in the treatment of osteoporosis.

5.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; RBCF, Rev. bras. ciênc. farm. (Impr.);43(4): 607-613, out.-dez. 2007. tab
Artigo em Português | LILACS | ID: lil-479330

RESUMO

O presente trabalho tem como objetivo comparar os métodos oficiais de determinação físico-química de produtos lácteos (extrato seco desengordurado, proteína, gordura e densidade) com metodologia de ultra-som. Foram analisados diferentes leites (integral e desnatado, convencional e orgânico), leites fermentados comerciais, bases lácteas para leites fermentados e soro de queijo, totalizando vinte produtos lácteos de características diferentes. O método por ultra-som é rápido e os resultados obtidos correlacionam-se àqueles das análises oficiais. Entretanto, é necessário o emprego de um perfil específico através da calibração do equipamento com base nas informações das análises oficiais. Os resultados deste trabalho exploratório sugerem a necessidade de se realizar um estudo com grande número de amostras a fim de validar as conclusões obtidas. As evidências descritas neste artigo são importantes para a indústria brasileira de produtos lácteos.


The present paper aims to compare the official methods of physical-chemical determination of dairy products (defatted dry matter, protein, fat and density) with methodology using ultra-sound. Different products were analyzed: milks (integral and skimmed conventional and organic), commercial fermented milks and dairy milk bases prepared in laboratory and whey totalizing twenty dairy products of different characteristics. The method using ultra-sound is fast and the results are correlated with those of the official analyses. However, the operator of the equipment should be attentive to employ a specific profile of the equipment according to the analysis to be carried out and, to calibrate the equipment based in the information obtained by the official analyses. The results of this exploratory article suggest the need to perform a study with a great number of samples in order to validate the obtained conclusions. The evidences described in this article are important for the Brazilian industry of dairy products.


Assuntos
Composição de Alimentos , Qualidade dos Alimentos , Iogurte/análise , Laticínios/análise , Leite , Ultrassom
6.
Arq. bras. med. vet. zootec ; 55(1): 27-34, fev. 2003. ilus, tab
Artigo em Português | VETINDEX | ID: vti-7576

RESUMO

Avaliaram-se dois protocolos de ultra-som no tratamento de lesões do tendão flexor digital superficial (TFDS). Foram estudados 18 eqüinos, nos quais foi injetada uma solução de colagenase a 0,25 por cento no TFDS esquerdo, à altura do terço médio da região metacarpiana. Os eqüinos foram divididos em: grupo A - tratado por ultra-som (UST) na freqüência de 3 MHz e intensidade de 1W/cm², no modo contínuo, por seis minutos; grupo B - tratado na mesma freqüência, intensidade e tempo, no modo pulsado; e grupo C - controle. Os tratamentos foram iniciados 48h após a indução da lesão, totalizando oito sessões. Os eqüinos foram estudados por 40 dias, avaliando-se o quadro clínico e a regressão dos sintomas. Por meio de exames ultra-sonográficos semanais avaliaram-se a área transversal e a ecogenicidade da lesão para estabelecimento do índice de severidade (IS). A lesão resultou em aumento médio de 1,5cm na circunferência da região metacarpiana, resposta à pressão digital de leve a moderada e grau de claudicação de 1 a 3. A regressão dos sintomas ocorreu, em média, nove dias no grupo A, 12 dias no grupo B e 21 dias no grupo C. O percentual de regressão no IS aos 40 dias foi de 42,5, 57,7 e 34,1, respectivamente. A avaliação histológica mostrou neovascularização pronunciada e maior atividade fibroblástica nos grupos tratados (A e B) comparados ao grupo-controle. Estes resultados sugerem que o UST é efetivo na redução dos sintomas clínicos da tendinite.(AU)


In order to evaluate two therapeutic ultrasound protocols for treatment of injuries of the superficial digital flexor tendon (SDFT) a study was performed in 18 horses. In each horse, a 0.25% solution of collagenase was injected in the middle of the left SDFT. The horses were randomly and equally divided into three groups. Horses from Group A were treated with therapeutic ultrasound of 3 MHz frequency and 1 W/cm2 intensity on continuous mode for six minutes; horses from Group B were treated with the same frequency, intensity, and time, but on pulsed mode; Group C was kept as controls. The treatment began 48 hours after the collagenase injection, totaling eight sessions. The horses were clinically evaluated for 40 days. Ultrasonographic images were evaluated weekly to score the severity rate (SR), which was based on echogenicity and cross sectional area of the lesion in the tendon. The induced lesion resulted on an average increase of 1.5cm in the shin circumference, pain response to digital pressure ranging from low to high and lameness ranging from grade 1 to 3. Regression of clinical signs were detected on average in nine days in Group A, 12 days in Group B, and 21 days in Group C. Decreases of the SR after 40 days were 42.5, 57.7 and 34.1% in groups A, B and C, respectively. Histological evaluation demonstrated intense neovascularization and fibroblastic activity on treated groups (A and B), when compared to the controls. These results suggest that UST is effective in reducing clinical signs of tendinitis.(AU)


Assuntos
Animais , Masculino , Feminino , Cavalos , Terapia por Ultrassom , Tendinopatia
7.
Neotrop. entomol ; 30(3): 497-499, Sept. 2001. tab
Artigo em Inglês | LILACS | ID: lil-514391

RESUMO

Os aparelhos repelentes de mosquitos Anti-Pic®, Mosquito Repeller® DX-600 e Bye-Bye Mosquito® foram avaliados em caixas de experimentação expondo-se a mão humana a adultos de Aedes albopictus (Skuse). Foram realizados dois conjuntos de experimentos baseados em exposições por 15 min. No primeiro, ambas mãos foram introduzidas na caixa, estando uma delas com o aparelho ligado. No segundo foi introduzida uma mão de cada vez, segurando o aparelho, ligado ou não. Os aparelhos falharam em mostrar eficiência em ambas as avaliações. Uma aparente proteção de 30,3 por cento pelo Anti-Pic® no primeiro conjunto de experimentos não foi confirmada no conjunto seguinte. Discute-se o valor desse recurso na prevenção da dengue.


The mosquito-repelling devices Anti-Pic®, Mosquito Repeller® DX-600 and Bye-Bye Mosquito® were evaluated in boxes for experimentation by exposing human hands to Aedes albopictus (Skuse) adults. Two sets of tests were performed based on 15 min. expositions. In the first set both hands were introduced in the box, one of them holding the device on. In the second set only one hand was introduced each time, holdind the device on or off. The devices failed to show efficiency in both evaluations. A seemingly 30.3 percent repellency due to Anti-Pic® in the first set of experiments was not confirmed in the second set. It was discussed the value of such devices for dengue prevention.

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