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1.
J Chromatogr A ; 1723: 464913, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38642449

RESUMEN

Mass spectrometry is characterized by its high sensitivity, ability to measure very low analyte concentrations, specificity to distinguish between closely related compounds, availability to generate high-throughput methods for screening, and high multiplexing capacity. This technique has been used as a platform to analyze fluid biomarkers for Alzheimer's disease. However, more effective sample preparation procedures, preferably antibody-independent, and more automated mass spectrometry platforms with improved sensitivity, chromatographic separation, and high throughput are needed for this purpose. This short communication discusses the development of a fiber-in-tube SPME-CapLC-MS/MS method to determine Aß peptides in cerebrospinal fluid obtained from Alzheimer's disease patients. To obtain the fiber-in-tube SPME capillary, we longitudinally packed 22 nitinol fibers coated with a zwitterionic polymeric ionic liquid into the same length of the PEEK tube. In addition, this communication compares this fiber-in-tube SPME method with the conventional HPLC scale (HPLC-MS/MS) and when directly coupled to CapESI-MS/MS without chromatographic separation, and, as a case study, discusses the benefits and challenges inherent in miniaturizing the flow scale of the sample preparation technique (fiber-in-tube SPME) to the CapLC-MS/MS system. Fiber-in-tube SPME-CapLC-MS/MS provided LLOQ ranging from 0.09 to 0.10 ng mL-1, accuracy ranging from 91 to 117 % (recovery), and reproducibility of less than 18 % (RSD). Analysis of the cerebrospinal fluid samples obtained from Alzheimer's disease patients evidenced that the method is robust. At the capillary scale (10 µL min-1), this innovative method presented higher analytical sensitivity than the conventional HPLC-MS/MS scale. Although fiber-in-tube SPME directly coupled to CapESI-MS/MS offers advantages in terms of high throughput, the sample was dispersed and non-quantitatively desorbed from the capillary at low flow rate. These results highlighted that chromatographic separation is important to decrease the matrix effect and to achieve higher detectability, which is indispensable for bioanalysis.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem , Enfermedad de Alzheimer/líquido cefalorraquídeo , Humanos , Espectrometría de Masas en Tándem/métodos , Microextracción en Fase Sólida/métodos , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/análisis , Cromatografía Líquida de Alta Presión/métodos , Límite de Detección , Biomarcadores/líquido cefalorraquídeo , Biomarcadores/análisis , Reproducibilidad de los Resultados
2.
J Chromatogr A ; 1713: 464518, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38000199

RESUMEN

Organic-silica hybrid monolithic materials have attracted considerable attention as potential stationary phases in separation science. These materials combine the advantages of organic polymer and silica-based monoliths, including easy preparation, lower back pressure, high permeability, excellent mechanical strength, thermal stability, and tunable surface chemistry with high surface area and selectivity. The outstanding chromatographic efficiency as stationary phase of hybrid monolithic capillary columns for capillary liquid chromatography and capillary electrochromatography has been reported in many papers. Organic-silica hybrid monolithic materials have also been extensively used in the field of sample preparation. Owing to their surface functionalities, these porous sorbents offer unique selectivity for pre-concentration of different analytes in the most complex matrixes by fast dynamic transport. These sorbents not only improve the analytical method sensitivity, but also introduce novelties in terms of extraction devices and instrument coupling strategies. The current review covers the period spanning from 2017 to 2023 and describes the properties of organic-inorganic hybrid monolithic materials, the present status of this technology and summarizes recent developments in their use as innovative sorbents for microextraction sample preparation techniques (solid phase microextraction with pipette tip, offline in-tube SPME, in-tube SPME online with LC, and in-tube SPME directly coupled with mass spectrometry). Aspects such as the synthesis methods (sol-gel process, one-pot approach, and polyhedral oligomeric silsesquioxanes-based procedure), characterization techniques, and strategies to improve extraction efficiency in various applications in different areas (environmental, food, bioanalysis, and proteomics) are also discussed.


Asunto(s)
Electrocromatografía Capilar , Dióxido de Silicio , Dióxido de Silicio/química , Cromatografía Liquida/métodos , Electrocromatografía Capilar/métodos , Microextracción en Fase Sólida/métodos , Polímeros
4.
Anal Bioanal Chem ; 415(18): 4003-4021, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36877264

RESUMEN

Alzheimer's disease (AD), a neurological disorder, is a major public health concern and the most common form of dementia. Its typical symptoms include memory loss, confusion, changes in personality, and cognitive impairment, which result in patients gradually losing independence. Over the last decades, some studies have focused on searching for effective biomarkers as early diagnostic indicators of AD. Amyloid-ß (Aß) peptides have been consolidated as reliable AD biomarkers and have been incorporated into modern diagnostic research criteria. However, quantitative analysis of Aß peptides in biological samples remains a challenge because both the sample and the physical-chemical properties of these peptides are complex. During clinical routine, Aß peptides are measured in the cerebrospinal fluid by immunoassays, but the availability of a specific antibody is critical-in some cases, an antibody may not exist, or its specificity may be inadequate, leading to low sensitivity and false results. HPLC-MS/MS has been reported as a sensitive and selective method for determining different fragments of Aß peptides in biological samples simultaneously. Developments in sample preparation techniques (preconcentration platforms) such as immunoprecipitation, 96-well plate SPME, online SPME, and fiber-in-tube SPME have enabled not only effective enrichment of Aß peptides present at trace levels in biological samples, but also efficient exclusion of interferents from the sample matrix (sample cleanup). This high extraction efficiency has provided MS platforms with higher sensitivity. Recently, methods affording LLOQ values as low as 5 pg mL-1 have been reported. Such low LLOQ values are adequate for quantifying Aß peptides in complex matrixes including cerebrospinal fluid (CSF) and plasma samples. This review summarizes the advances in mass spectrometry (MS)-based methods for quantifying Aß peptides and covers the period 1992-2022. Important considerations regarding the development of the HPLC-MS/MS method such as the sample preparation step, optimization of the HPLC-MS/MS parameters, and matrix effects are described. Clinical applications, difficulties related to analysis of plasma samples, and future trends of these MS/MS-based methods are also discussed.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Humanos , Péptidos beta-Amiloides/química , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Enfermedad de Alzheimer/diagnóstico , Anticuerpos , Biomarcadores/líquido cefalorraquídeo , Fragmentos de Péptidos/química
5.
Talanta ; 254: 124186, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36521326

RESUMEN

Current research efforts at neurological diseases have focused on identifying novel biomarkers to aid in diagnosis, to provide accurate prognostic information, and to monitor disease progression. This study presents the direct coupling of fiber-in-tube solid-phase microextraction to tandem mass spectrometry as a reliable method to determine amyloid beta peptides (Aß38, Aß40, and Aß42) as biomarkers for Alzheimer's disease in cerebrospinal fluid (CSF) samples. To obtain the biocompatible fiber-in-tube SPME capillary, a PEEK tube segment was longitudinally packed with fine fibers [nitinol wires coated with a zwitterionic polymeric ionic liquid], to act as selective extraction medium. The fiber-in-tube SPME-MS/MS method integrated analyte extraction/enrichment and sample cleanup (exclusion of interferents) into one step. The method provided lower limits of quantification (LLOQ: 0.2 ng mL-1 for Aß38 and 0.1 ng mL-1 for Aß40 and Aß42), high precision (CV lower than 11.6%), and high accuracy (relative standard deviation lower than 15.1%). This method was successfully applied to determine Aß peptides in CSF samples obtained from AD patients (n = 8) and controls (healthy volunteers, n = 10). Results showed that Aß42 levels in the CSF samples obtained from AD patients were significantly lower compared to healthy controls (p < 0.05). On the basis of the ROC analysis results, the Aß42/Aß40 ratio (AUC = 0.950, p < 0.01; 95%) performed significantly better than Aß42 alone (AUC = 0.913, p < 0.01; 95%) in discriminating between AD patients and healthy controls and presented better diagnostic ability for AD. The novelties of this study are not only related to evaluating Aß peptides as AD biomarkers, but also to demonstrating direct online coupling of fiber-in-tube SPME with MS/MS as a quantitative high-throughput method for bioanalysis.


Asunto(s)
Enfermedad de Alzheimer , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem , Humanos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/química , Biomarcadores , Fragmentos de Péptidos , Microextracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos
6.
Rev. bras. cineantropom. desempenho hum ; 25: e95102, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1529714

RESUMEN

Abstract The present study aimed to describe a study protocol for Orienteers' anthropometric characteristics and physical activity level. This is an individualized, observation and cross-sectional pilot study, that has encompassed three Orienteers (2 Portuguese men and 1 Spanish woman) with mean age 22.6 ± 3.78 years and 8.0 ± 2.64 consecutive years of Orientation practice. In total, 26 anthropometric variables were assessed: four basic measurements, nine skinfolds, nine girths and four breadths; Body Mass Index was calculated, as well as body composition and somatotype (according to the Heath-Carter method). The International Physical Activity Questionnaire - Short Form was used to obtain the score expressed as metabolic equivalent and the energy expenditure in kilocalories, both during the reference week. Mean somatotype recorded for Orienteering athletes could be defined as balanced mesomorph. Scores recorded for different physical activity/ inactivity expressed domains have shown high-energy expenditure. Sports Science Professionals can use the herein proposed protocol to improve Orienteers' training.


Resumo Objetivou-se descrever um protocolo de estudo das características antropométricas e do nível de atividade física de Orientistas. Trata-se de um estudo piloto, caracterizado como individualizado, observacional e transversal. Participaram do estudo três Orientistas (2 homens Portugueses e 1 mulher Espanhola) com 22,6 ± 3,78 anos de idade e 8,0 ± 2,64 anos de prática consecutiva de Orientação. Foram avaliadas 26 variáveis antropométricas: quatro medidas básicas, nove dobras cutâneas, nove circunferências e quatro diâmetros ósseos; Índice de Massa Corporal foi calculado, bem como a composição corporal e o somatotipo (de acordo com o método Heath-Carter). O Questionário Internacional de Atividade Física, versão curta e auto-administrado, foi utilizado para obter a pontuação expressa como equivalente metabólico e o dispêndio energético em quilocalorias, ambos durante a semana de referência. A média do somatotipo dos atletas de Orientação pode ser definida como mesomorfo balanceado. As pontuações dos diferentes domínios da atividade física/ inatividade expressas, demonstraram um elevado dispêndio energético. Profissionais das Ciências do Esporte podem usar o protocolo proposto para melhor controle do treinamento de Orientistas.

7.
Rev. Odontol. Araçatuba (Impr.) ; 43(2): 29-34, maio-ago. 2022. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: biblio-1362016

RESUMEN

A articulação temporomandibular está vunerável a várias condições de anormalidades já bastante conhecidas, dentre elas, o deslocamento do disco articular sem redução, considerado pela literatura o mais comum das patologias desta região. A deterioração do quadro pode ser um indicativo da necessidade cirúrgica. Em específico, no deslocamento de disco sem redução, o reposicionamento definitivo pode ser adquirido através de discopexia e artrocentese. O presente trabalho tem como objetivo relatar um caso clínico de deslocamento de disco articular bilateral sem redução, apresentando a importância da fisioterapia associada à abordagem cirúrgia na recuperação da função mandibular, bem como, reforçar a importância de uma abordagem conjunta entre análise clínica e imaginológica para resolução de casos. Paciente feminino cursando com diversos sintomas em face e pescoço de forma progressiva ao longo de dois anos foi submetida a cirurgia na articulação temporo-mandibular, onde foi feita a discopexia através de ancoragem dos discos articulares com parafusos. A avaliação física, assim como, a imaginológica, ajudaram na confirmação do diagnóstico. A abordagem cirurgica adotada no tratamento deste caso foi descrita na literatura desde o final do século XIX. Conclui-se que, o método utilizado no tratamento do deslocamento de disco sem redução deve ser baseado nos sinais e sintomas do paciente, cuja abordagem deve ser readequada de acordo com as mudanças do quadro apresentado. Nesta análise, a abordagem cirúrgica associada à fisioterapia específica para as estruturas musculoesquelética da face trouxeram resultados positivos(AU)


The temporomandibular joint is responsible for several well-known conditions of abnormalities, among them, the joint disc displacement without reduction, considered by the literature the most common pathology of this region. Deterioration of the condition may be indicative of surgical need. Specifically, in displacement disc without reduction, definitive repositioning can be achieved through discopexy and arthrocentesis. The aim of the present study is to report a case of unilateral articular disc displacement without reduction, as well the importance of physiotherapy associated with the surgical approach in the recovery of mandibular function, as well as reinforcing the importance of a joint approach between clinical and imaging analysis for case resolution. Female patient with several symptoms in the face and neck progressively over two years, underwent surgery in the temporomandibular joint, where discopexy was performed by anchoring the articular discs with screws. The physical assessment, as well as the imaging, helped to confirm the diagnosis. The surgical approach adopted in the treatment of this case has been described in the literature since the end of the 19th century. In conclusion, the method used to treat articular disc displacement without reduction should be based on the patient's signs and symptoms, whose approach should be readjusted according to the changes in the presented picture. In this analysis, the surgical approach associated with specific physiotherapy for the musculoskeletal structures of the face brought positive results(AU)


Asunto(s)
Humanos , Femenino , Adulto , Disco de la Articulación Temporomandibular , Disco de la Articulación Temporomandibular/lesiones , Luxaciones Articulares , Articulación Temporomandibular/lesiones , Modalidades de Fisioterapia , Disco de la Articulación Temporomandibular/cirugía , Disco de la Articulación Temporomandibular/diagnóstico por imagen , Artrocentesis
8.
J Chromatogr A ; 1668: 462925, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35263675

RESUMEN

Miniaturized liquid chromatography (LC) has been recognized as one of the most important analytical methods in several research fields. Reduced analytical work-scale provides superior chromatographic resolution and decreases sample and organic solvent consumption. However, frequent clogging of tubing connections and use of small sample volumes are significant limitations when high throughput and sensitive analyses are required. Effective sample preparation could help to overcome these limitations. Online coupling of sample preparation techniques (such as column switching and in-tube solid-phase microextraction) with these miniaturized systems may result in more sensitive and reproducible analyses, improving analytical efficiency. This review describes the most common online miniaturized LC configurations, and the main applications of current online sample preparation techniques coupled to miniaturized LC systems in the bioanalytical, omics, and environmental areas. Relevant features, and challenges of these systems, and innovative sorbents, including restricted access materials, monoliths, and immunosorbents is also discussed.


Asunto(s)
Microextracción en Fase Sólida , Manejo de Especímenes , Cromatografía Liquida/métodos , Inmunoadsorbentes , Microextracción en Fase Sólida/métodos , Solventes
9.
Anal Chim Acta ; 1193: 339394, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35058015

RESUMEN

Alzheimer disease (AD) is a neurodegenerative disorder characterized by extracellular accumulation of amyloid-ß peptide (Aß) in the brain interstitium. Human serum albumin (HSA) highly binds to Aß in blood plasma and is thought to inhibit plaque formation in peripheral tissue. Thus, the evaluation of albumin binding to Aß is an important key to understand the dynamics of these molecules in the biological system of patients with AD. In this work, a fiber-in-tube solid-phase microextraction (fiber-in-tube SPME) and ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to estimate Aß fraction binding to HSA in cerebrospinal fluid (CSF) and plasma samples. Crosslinked zwitterionic polymeric ionic liquid (zwitterionic PIL)-coated nitinol wires were developed and packed into a polyether ether ketone (PEEK) capillary for a fiber-in-tube SPME and UHPLC-MS/MS method. Zwitterionic PIL sorbent was synthetized from 1-vinyl-3-(butanesulfonate)imidazolium ([VIm+C4SO3-]) and 1,12-di(3-vinylimidazolium)dodecane dibromide ([(VIm)2C12]2[Br]) monomers by in-situ thermally-initiated polymerization. Morphological characterization by scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed a decrease in the surface roughness of the nitinol wires from ∼17 nm to 1 nm after the in-situ polymerization. The zwitterionic PIL sorbent selectively preconcentrates Aß through a two-pronged interaction mechanism. The fiber-in-tube SPME and UHPLC-MS/MS method presented lower limits of quantification (LLOQ) of 0.4 ng mL-1 for Aß38 and 0.3 ng mL-1 for Aß40 and Aß42, a linear range from LLOQ values to 15 ng mL-1 with coefficients of determination higher than 0.99, precision with coefficient of variation (CV) values ranging from 2.1 to 7.3% and accuracy with relative standard deviation (RSD) values from -0.3 to 7.4. This method was successfully applied to evaluate the binding of HSA to Aß in cerebrospinal fluid (CSF) and plasma samples.


Asunto(s)
Péptidos beta-Amiloides , Líquidos Iónicos , Aleaciones , Proteínas Portadoras , Cromatografía Líquida de Alta Presión , Humanos , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem
10.
Eur Heart J Digit Health ; 3(1): 98-104, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36713991

RESUMEN

Aims: The existing instruments for assessing heart rate (HR) and heart rate variability (HRV) require contact area. This is difficult to obtain from specific groups of patients and from those moving. The aim of this study was to validate the use of the HRVCam software for measuring HR and HRV in healthy adults. Methods and results: The HR and HRV variables were evaluated in terms of time and frequency using a webcam and Polar® S810i. The Shapiro-Wilk test was used to test the normality of the data, and the Pearson's correlation coefficient (r) was used to identify the possible correlation between the two instruments. The size of the effect was calculated based on a generalized linear model, and the Bland-Altman plots were used to analyse the agreement between the methods. The level of significance for all analyses was set at P < 0.05. We evaluated 102 participants, of whom 52% were men; 83.3% were aged between 18 and 29.9 years; and 84.3% were single. Conclusion: There was a good agreement and moderate to strong correlations among all analysed variables. The biases were low, except for the low frequency/high frequency measures. Moreover, the difference between the samples was small to moderate. The results of this study corroborate the use of HRVCam for measuring HR and HRV.

11.
Rev. cir. traumatol. buco-maxilo-fac ; 21(2): 35-38, abr.-jun. 2021. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: biblio-1390983

RESUMEN

Introdução: O cisto do ducto nasopalatino é uma lesão não odontogênica com etiologia controversa. No entanto, fatores irritantes, como trauma local e infecções bacterianas, podem estimular o remanescente epitelial do ducto nasopalatino, levando a uma formação cística. Sua predileção ocorre em homens adultos entre a quarta e a sexta décadas. Geralmente é assintomático, sendo detectado por exame de rotina. O objetivo do presente estudo é apresentar e discutir um caso de cisto do Ducto Nasopalatino, analisando-se os aspectos clínicos e imaginológicos da patologia em face, comparando-o com dados provenientes da literatura corrente. Relato de caso: Como resultado este artigo apresenta a abordagem de um caso cirúrgico de cisto do Ducto Nasopalatino em face, assintomático, descoberto em exame imaginológico de rotina, biopsiado e enucleado cirurgicamente, com acompanhamento de 5 anos sem recidiva. Considerações finais: É evidente, portanto, que a literatura ainda não é unânime quanto ao aspecto epidemiológico, contudo, se reafirma a forma de abordagem cirúrgica excisional como tratamento eficaz definitivo. Faz-se necessária, portanto, a análise clínica, imaginológica e histopatológica para a confirmação diagnóstica da lesão. A observação de tais aspectos é de fundamental importância para um tratamento eficaz e definitivo, reduzindo as chances de recidiva... (AU)


Introduction: The nasopalatine duct cyst is a non-odontogenic lesion with controversial etiology. However, irritating factors, such as local trauma and bacterial infections, can stimulate the epithelial remnant of the nasopalatine duct, leading to a cystic formation. Its predilection occurs in adult men between the fourth and sixth decades. It is usually asymptomatic, being detected by routine examination. Objectives: To present and discuss a case of cyst of the Nasopalatine duct, analyzing the clinical and imaging aspects of the pathology in the face, comparing it with data from the current literature. Case Report: As a result, this article presents the approach of a surgical case of Nasopalatine Ducto cyst in the face, asymptomatic, discovered in a routine imaging exam, biopsied and surgically enucleated, with a 5-year follow-up without recurrence. Final considerations: It is evident, therefore, that the literature is not yet unanimous in terms of the epidemiological aspect, however, the form of excisional surgical approach as a definitive effective treatment is reaffirmed. Therefore, clinical, imaging and histopathological analysis is necessary to confirm the diagnosis of the lesion. The observation of such aspects is of fundamental importance for an effective and definitive treatment, reducing the chances of recurrence... (AU)


Asunto(s)
Humanos , Femenino , Adulto , Recurrencia , Quistes Odontogénicos/cirugía , Quistes Odontogénicos/patología , Infecciones Bacterianas , Paladar Duro/lesiones
12.
Anal Chim Acta ; 1165: 238110, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-33975700

RESUMEN

Fiber-in-tube solid-phase microextraction (fiber-in-tube SPME) with short capillary longitudinally packed with fine fibers as extraction device allows direct coupling to high performance liquid chromatography (HPLC) systems to determine weakly volatile or thermally labile compounds. This technique associates the advantages of miniaturized and analytical on-line systems. Major achievements include the use of different capillaries (fused-silica, copper, stainless steel, polyetheretherketone (PEEK), or poly(tetrafluoroethylene) (PTFE)) that are packed with neat fibers (Zylon®, silk, or Kevlar 29®) or fibers (stainless steel, basalt, or carbon) functionalized with selective coatings (aerogels, ionic liquids (ILs), polymeric ionic liquids (PILs), molecularly imprinted polymers (MIPs), layered double hydroxides (LDHs), or conducting polymer). This review outlines the fundamental theory and the innovative extraction materials for fiber-in-tube SPME-HPLC systems and highlights their main applications in environmental and bioanalyses.

13.
J Sep Sci ; 44(8): 1662-1693, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33528909

RESUMEN

In-tube solid-phase microextraction with a capillary column as extraction device can be directly coupled with high-performance liquid chromatography systems (HPLC). The in-tube solid-phase microextraction technique has been continuously developed since it was introduced in 1997. New couplings have also been evaluated on the basis of state-of-the-art HPLC instruments. Different types of capillaries (wall-coated open tubular, porous layer open tubular, sorbent-packed, porous monolithic rods, or fiber-packed) with selective stationary phases (monoliths, magnetic nanoparticles, conducting polymers, restricted access materials, ionic liquids, carbon, deep eutectic solvents, and hybrid materials) have been developed to boost in-tube solid-phase microextraction performance (sorption capacity and selectivity). This technique has been successfully applied to analyze biological samples (serum, plasma, whole blood, hair, urine, milk, skin, and saliva) for therapeutic drug monitoring, to study biomarkers, to detect illicit drugs, to conduct metabolomics studies, and to assess exposure to drugs. This review describes current advances in in-tube solid-phase microextraction extraction devices and their application in bioanalysis.


Asunto(s)
Carbono/química , Líquidos Iónicos/química , Microextracción en Fase Sólida , Cromatografía Líquida de Alta Presión , Tamaño de la Partícula , Porosidad , Solventes/química , Propiedades de Superficie
14.
Med Mycol ; 59(5): 476-485, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32823281

RESUMEN

Drug repositioning has been an important ally in the search for new antifungal drugs. Statins are drugs that act to prevent sterol synthesis in both humans and fungi and for this reason they are promissory candidates to be repositioned to treat mycoses. In this study we evaluated the antifungal activity of atorvastatin by in vitro tests to determine the minimum inhibitory concentration against azole resistant Candida albicans and its mechanisms of action. Moreover, the efficacy of both atorvastatin-loaded oral and vaginal emulgels (0.75%, 1.5% and 3% w/w) was evaluated by means of in vivo experimental models of oral and vulvovaginal candidiasis, respectively. The results showed that atorvastatin minimal inhibitory concentration against C. albicans was 31.25 µg/ml. In oral candidiasis experiments, the group treated with oral emulgel containing 3.0% atorvastatin showcased total reduction in fungal load after nine days of treatment. Intravaginal delivery atorvastatin emulgel showed considerable effectiveness at the concentration of 3% (65% of fungal burden reduction) after nine days of treatment. From these findings, it is possible to assert that atorvastatin may be promising for drug repositioning towards the treatment of these opportunistic mycoses.


Atorvastatin is a statin drug that presents antifungal activity. This study showed that atorvastatin-containing oral and vaginal emulgels were able to treat vulvovaginal and oral candidiasis of infected animal model. Therefore, we showcased that atorvastatin may be a possible therapeutic agent in order to be a used to control opportunistic mucosal fungal infections caused by Candida albicans.


Asunto(s)
Atorvastatina/farmacología , Atorvastatina/uso terapéutico , Candida albicans/efectos de los fármacos , Candidiasis Bucal/tratamiento farmacológico , Candidiasis Vulvovaginal/tratamiento farmacológico , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Azoles/farmacología , Candidiasis Bucal/microbiología , Candidiasis Vulvovaginal/microbiología , Modelos Animales de Enfermedad , Reposicionamiento de Medicamentos , Farmacorresistencia Fúngica , Femenino , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Ratas , Resultado del Tratamiento
15.
J Chromatogr A ; 1636: 461766, 2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33316562

RESUMEN

To evaluate the endocannabinoid system in an animal model of Parkinson's disease, in-tube solid-phase microextraction (in-tube SPME) was directly coupled to a tandem mass spectrometry (MS/MS) system for determination of the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in rat brain samples. In-tube SPME-which consisted of a microtube of restricted access material (RAM) with a hydrophilic diol external surface and a hydrophobic octyl inner surface-efficiently excluded (up to 95%) macromolecules from the biological samples and selectively pre-concentrated the analytes. In-tube SPME parameters, such as sample volume, mobile phases, flow rate, and pre-concentration time, were evaluated to improve the extraction efficiency and throughput performance. The selectivity of the in-tube SPME and MS/MS (MRM mode) techniques allowed them to be directly coupled online, which dismissed the need for the chromatographic separation step. The in-tube SPME-MS/MS method was validated and shown to be linear from 6.0 to 30.0 ng mL-1 for AEA and from 10.0 to 100.0 ng mL-1 for 2-AG; the intra- and inter-assay accuracy and precision were lower than 15%. Parallelism between the calibration curves constructed in the matrix and aqueous solution confirmed that there was no matrix effect. The method allowed endogenous concentrations of AEA and 2-AG to be determined in rat brain striatum from unilaterally 6-hydroxydopamine-lesioned animals. The concentrations of these endocannabinoids in striatum ipsilateral and contralateral to the lesion differed significantly (p<0.001).


Asunto(s)
Ácidos Araquidónicos/análisis , Encéfalo/metabolismo , Endocannabinoides/análisis , Glicéridos/análisis , Alcamidas Poliinsaturadas/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Ácidos Araquidónicos/aislamiento & purificación , Ácidos Araquidónicos/normas , Encéfalo/efectos de los fármacos , Calibración , Cromatografía Líquida de Alta Presión , Endocannabinoides/aislamiento & purificación , Endocannabinoides/normas , Glicéridos/aislamiento & purificación , Glicéridos/normas , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Oxidopamina/farmacología , Alcamidas Poliinsaturadas/aislamiento & purificación , Alcamidas Poliinsaturadas/normas , Ratas , Ratas Wistar , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem/normas
16.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1288220

RESUMEN

resumo A pandemia da COVID-19 afetou diversas atividades humanas, tais como práticas de medições antropométricas, desde o campo clínico e de pesquisa até o campo do ensino. Dada a falta de vacinas e/ou medicamentos eficazes contra a COVID-19, a Organização Mundial da Saúde (OMS) recomendou medidas de prevenção e enfrentamento da doença. Essas recomendações foram posteriormente endossadas pela Sociedade Internacional para o Avanço da Cineantropometria/ International Society for the Advancement of Kinanthropometry (ISAK), com adaptações às rotinas antropométricas, que complementamos para aplicação abrangente nos diversos segmentos de atuação da antropometria. Este ponto de vista visa enfatizar e contribuir às considerações de segurança das rotinas antropométricas em um mundo pós-COVID-19. Entende-se aqui que o protocolo de biossegurança apresentado neste ponto de vista para retorno e continuidade das atividades antropométricas, no mundo inteiro, independentemente da formação/ capacitação/ atuação profissional, no que diz respeito à vida e às comunidades, também pode ter aplicação recorrente no combate a outros patógenos respiratórios semelhantes para se transformarem em pandemias no futuro. Sugere-se o desenvolvimento de vídeos demonstrativos das recomendações deste ponto de vista para reforçar as boas práticas higiênico-sanitárias a serem adotadas pelos profissionais da antropometria na realização das medições do corpo humano.


abstract The COVID-19 pandemic has affected several human activities such as anthropometrics measures practices, from the clinical and research fields to the teaching field. Given the lack of effective vaccines and/or drugs against COVID-19, the World Health Organization (WHO) has recommended taking measures to prevent and cope with the disease. These recommendations were subsequently endorsed by the International Society for the Advancement of Kinanthropometry (ISAK), with adaptations to anthropometric routines, which were made to enable comprehensive application in several anthropometry segments. This point of view aims to emphasize and contribute to security considerations about anthropometric routines in the post-COVID-19 world. It is herein understood that the biosafety protocol presented under this point of view to enable the return and continuation of anthropometric activities, worldwide, regardless of professional training/ qualification/ performance, with respect to life and communities, may also have recurring application to fight other respiratory pathogens with similar potential to turn into pandemics in the future. Demonstrative videos presenting these recommendations, based on this point of view, should be developed to help reinforcing the good hygienic-sanitary practices to be adopted by anthropometry professionals who carry out human body measurements.

18.
Biomed Pharmacother ; 129: 110432, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32768935

RESUMEN

Gastrointestinal diseases are very common problems; available treatments are very limited and come with a range of side effects. Coumarins are an extensive class of phenolic compounds that can be found in plants, fungi and bacteria. The 7-hydroxycoumarin, also known as umbelliferone (UMB), is a compound that comes from coumarin and has been showing biological activities in other studies. As of this scenario, the present study was designed to evaluate the acute oral toxicity, mutagenic, antidiarrheal, anti-bacterial, and antiulcerogenic effects, and antioxidant capacity of UMB. An investigation was conducted through the hippocratic screening method and through histopathological analysis in animals to evaluate the effects of acute oral administration of a dose of 50, 100 and 200 mg/kg of UMB. A micronucleus test on peripheral blood of Swiss mice, which were orally treated with three doses (50, 100 and 200 mg/kg), was conducted to evaluate mutagenic activities. The antiulcerogenic activity was accomplished through the ethanol-induced damage method. Antidiarrheal activities were tested for inducing diarrhea with castor oil and evaluating intestinal transit duration; additionally, the antimicrobial effect against some enteropathogenic bacteria was analyzed. Finally, the antioxidant capability was determined by the capacity of the UMB sample to kidnap the stable radical 2,2-diphenyl-1-picrylhydrazyl. Of the evaluated doses, signs of toxicity after acute administration of the compound were not observed. UMB presented antiulcerogenic activity (100 and 200 mg/kg), which was explained because of its antioxidant capacity. A gastro protective effect was similar to the positive control, and the UMB was able to significantly reduce intestinal transit, and also diarrheal symptoms. Furthermore, UMB had an anti-bacterial effect with minimum inhibitory concentration fluctuating between 62.5 and 1000 µg/mL. Based on these findings, we can suggest that UMB has important biological activities in vivo and in vitro and is not toxic under the evaluated circumstances, which demonstrates its large potential for pharmacological use.


Asunto(s)
Antiulcerosos/farmacología , Antidiarreicos/farmacología , Diarrea/prevención & control , Úlcera Gástrica/prevención & control , Umbeliferonas/farmacología , Animales , Antibacterianos/farmacología , Antiulcerosos/toxicidad , Antidiarreicos/toxicidad , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Aceite de Ricino , Defecación/efectos de los fármacos , Diarrea/inducido químicamente , Diarrea/fisiopatología , Modelos Animales de Enfermedad , Etanol , Motilidad Gastrointestinal/efectos de los fármacos , Masculino , Ratones , Estómago/efectos de los fármacos , Estómago/patología , Úlcera Gástrica/inducido químicamente , Umbeliferonas/toxicidad
19.
Motrivivência (Florianópolis) ; 32(63): [1-17], Jul. 2020.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1148054

RESUMEN

Este ensaio objetiva abordar a relação entre esporte e a questão racial, com reflexo nas práticas profissionais das Ciências do Esporte. Consideramos que essa relação é deturpada por estereótipos até os dias atuais com explicações pseudo-científicas, reducionismos filosóficos, teóricos e operacionais, inválidos e insustentáveis nas suas apropriações, porém raramente são desafiados de forma eficaz. Sugerimos o desenvolvimento de um trabalho orientado por princípios inclusivistas que permitam uma pedagogia do corpo no esporte, produzida no interior das relações sociais, com ações mais abrangentes e preocupadas com a diversidade humana.


This essay aims to discuss the relationship between sport and the racial question, with reflection on the professional practices of Sport Sciences. We consider this relationship to be distorted by stereotypes to the present day with pseudo-scientific explanations, philosophical, theoretical and operational reductions, invalid and unsustainable in their appropriations, but rarely are effectively challenged. We suggest a shift of conceptions to the development of a work guided by the principles of coeducation and regionalism, with integration/inclusion and situations of respect, that allows a pedagogy of the body in the sport, produced within social relations, with more comprehensive and preoccupied actions with human diversity.


Este ensayo tiene el objetivo abordar la relación entre deporte y la cuestión racial, con reflejo en las prácticas profesionales de las Ciencias del Deporte. Consideramos que esta relación es distorsionada por estereotipos hasta los días actuales con explicaciones pseudo-científicas, reduccionismos filosóficos, teóricos y operativos, inválidos e insostenibles en sus apropiaciones, pero rara vez son desafiados de forma eficaz. Se sugiere un desplazamiento de concepciones para el desarrollo de un trabajo orientado por los principios de la coeducación y regionalismo, con integración/inclusión y situaciones de respeto, que permita una pedagogía del cuerpo en el deporte, producida en el interior de las relaciones sociales, con acciones más amplias y preocupadas con la diversidad humana.

20.
Anal Chem ; 91(8): 4969-4974, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30901521

RESUMEN

To achieve high separation power of complex samples using multidimensional gas chromatography (MDGC), the selectivity of the employed stationary phases is crucial. The nonpolar × polar column combination remains the most popular column set used in MDGC. However, resolution of mixtures containing light analytes possessing very similar properties remains a formidable challenge. The development of stationary phases that offer unique separation mechanisms have the potential to significantly improve MDGC separations, particularly in resolving coeluting peaks in complex samples. For the first time, a stationary phase containing silver(I) ions was successfully designed and employed as a second-dimension column using comprehensive two-dimensional gas chromatography (GC × GC) for the separation of mixtures containing alkynes, dienes, terpenes, esters, aldehydes, and ketones. Compared with a widely used nonpolar and polar column set, the silver-based column exhibited superior performance by providing better chromatographic resolution of coeluting compounds. A mixture of unsaturated fatty acids was successfully separated using a GC × GC method in which the elution order in the second dimension was highly dependent on the number of double bonds within the analytes.

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