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1.
Int. j. morphol ; 42(4): 1005-1010, ago. 2024. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1569246

RESUMO

SUMMARY: In this study, we aim to share the volumes of the carpal bone and the ratio of these volumes to the total volume of wrist bones from Computed Tomography (CT) images obtained from individuals of different ages and sex using 3D Slicer. Right wrist CT images of 0.625 mm slice thickness of 42 healthy individuals (21 female, 21 male) of both sexes were included in our study. Volume calculations were made by loading the images into 3D Slicer, an open-source software package. In this study, mean capitate volume was the largest in both sexes (male 3479.9±679.2; female 2207.1±272.1 mm3), while pisiform had the smallest mean volume (male 810.0±141.2; female 566.6±97.7 mm3). This order was ordered from largest to smallest as hamate, scaphoid, trapezium, lunate, triquetrum, trapezoid, and pisiform. According to this study, carpal bone volumes were larger in males than in females (p0.05). In this study, it was seen that carpal bone volume differed according to sex. However, it was observed that the bone volumes of both sexes took up the same amount in the total bone volume. This information will be very useful in sex determination, 3D anatomical material creation, implant applications and reconstructive surgery.


Nuestro objetivo fue determinar los volúmenes de los huesos del carpo y la relación entre estos volúmenes y el volumen total de estos huesos a partir de imágenes de TC obtenidas de individuos de diferentes edades y sexos utilizando 3D Slicer. En el estudio se incluyeron imágenes de TC del carpo de la mano derecha de los participantes en el estudio, con un grosor de corte de 0,625 mm, en 42 individuos sanos (21 mujeres, 21 hombres) de ambos sexos. Los cálculos de volumen se realizaron cargando las imágenes en 3D Slicer, un paquete de software de código abierto. El volumen medio del hueso capitado fue el mayor en ambos sexos (hombre 3479,9 ± 679,2; mujer 2207,1 ± 272,1 mm3), mientras que el hueso pisiforme tuvo el volumen medio más pequeño (hombre 810,0 ± 141,2; mujer 566,6 ± 97,7 mm3). De mayor a menor el volumen de los otros huesos fue: hamato, escafoides, trapecio, lunato, piramidal, trapezoide y pisiforme. Según este estudio, los volúmenes óseos del carpo eran mayores en hombres que en mujeres (p0,05). En este estudio se observó que el volumen de los huesos del carpo difería según el sexo. Sin embargo, se observó que los volúmenes óseos de ambos sexos ocuparon la misma cantidad del volumen óseo total. Esta información será de gran utilidad en la determinación del sexo, creación de material anatómico 3D, aplicaciones de implantes y cirugía reconstructiva.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Ossos do Carpo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Caracteres Sexuais , Imageamento Tridimensional , Fatores Sexuais , Titulometria
2.
Respirar (Ciudad Autón. B. Aires) ; 15(2): 94-103, jun2023.
Artigo em Espanhol | LILACS | ID: biblio-1437544

RESUMO

Introducción: se considera aceptable (TitAcept) una prueba con CPAP automático en domicilio (APAP) cuando su uso es ≥ a 4 horas/noche y el índice de apneas residuales (IAHr) ≤ 10 eventos/hora (AASM). Sin embargo, todas las variables relacionadas con la calidad de este procedimiento no se conocen completamente. Objetivo: evaluar la cali-dad de la titulación con APAP en el domicilio. Material y métodos: estudio retrospectivo en pacientes "naïve" de CPAP. El criterio de TitAcept seleccionó dos grupos y la regresión logística múltiple identificó predictores de prueba no aceptables. Resultados: incluimos 1325 TitAcept; 941 hombres (71%), edad: 57 ± 12,4 años, IMC: 32,3 ± 8,8 kg/m2, IAH: 34,2 ± 19 ev/h. La titulación alcanzó 3,4 ± 3,5 noches, adherencia: 379 minutos/noche; pre-sión efectiva: 8,7 ± 1,7 cm H2O, IAHr; 3,1 ± 2,4 ev/h y fugas 16,1 ± 8,7 litros/min. Fueron predictores; edad ≥ 50 años; OR: 1,62 (IC95%: 1,23-3,46), p: 0.0005 y máscara orona-sal; OR: 2,49 (IC95%: 1,79-3,46), p: 0.0001. Conclusiones: una significativa proporción de pacientes que realizaron una titulación no vigilada con APAP en domicilio no alcan-zaron criterios de calidad adecuada. La edad ≥ 50 años y el uso de máscara oronasal se asocian con menor calidad en la prueba, de acuerdo a criterios preestablecidos. (AU)


Introduction: automated CPAP (APAP) titration at home is considered acceptable (Tit-Accept) when its device is used ≥ 4 hours/night and the residual apnea index (AHIr) es ≤ 10 events/hour (AASM). However, all the variables related to quality of this procedure are not fully known. Objective: to assess the quality of the titration with APAP at home.Material and Methods: retrospective study in CPAP "naïve" patients. The TitAccept criteri-on selected two groups and multiple logistic regression identified predictors of non-ac-ceptable titration. Results: we included 1325 TitAccept; 941 men (71%), age: 57 ± 12.4 years, BMI: 32.3 ± 8.8 kg/m2, baseline AHI: 34.2 ± 19 ev/h. The titration reached 3.4 ± 3.5 nights, adherence: 379 minutes/night; effective pressure: 8.7 ± 1.7 cmH2O, AHIr; 3.1 ± 2.4 ev/h and leaks 16.1 ± 8.7 liters/min. The predictors were; age ≥ 50 years; OR: (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Titulometria/métodos , Pressão Positiva Contínua nas Vias Aéreas/métodos , Máscaras , Grupos Etários
3.
Analyst ; 148(9): 2133-2140, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37039548

RESUMO

An auto titrator system was developed to accurately and precisely detect colorimetric endpoints for spectrochemical titrations. This system was constructed using inexpensive components such as a Raspberry Pi® single-board computer, 3D-printed components, and a commercially available spectral sensor. The auto titrator was evaluated by performing a standard method for determination of water hardness. Regardless of analyst experience, the auto titrator performed better than the traditional titration approach that involves manual dosing of titrant and visual detection of the endpoint. Inter-day, intra-day, inter-instrumental, and intra-instrumental validation studies were performed to establish the accuracy and precision of endpoint detection. The auto titrator eliminates the subjective bias in color perception and produces accurate and precise endpoint results.


Assuntos
Colorimetria , Água , Colorimetria/métodos , Titulometria/métodos
4.
Artigo em Inglês | LILACS, CUMED | ID: biblio-1508227

RESUMO

Introducción: Debido a la necesidad de un diagnóstico precoz de los trastornos neurodegenerativos, se ha intentado armonizar los criterios diagnósticos mediante métodos morfométricos basados en técnicas de neuroimagen, pero aún no se han obtenido resultados concluyentes. Objetivo: Determinar el volumen ventricular debido a su amplio uso como marcador de atrofia cerebral e identificar el efecto del sexo sobre estas estructuras, según el tipo de cráneo, estimado a partir de técnicas de imagen de tomografía computarizada multicorte. Métodos: Se desarrolló un estudio observacional y descriptivo en 30 sujetos con funciones neurocognitivas y exploración neuropsiquiátrica normales, con edades comprendidas entre 45 y 54 años, a los que se les realizó una tomografía computarizada multicorte simple de cráneo. Se utilizó un método de segmentación de imágenes basado en la homogeneidad. Resultados: Los volúmenes ventriculares mostraron una correlación significativa y positiva entre ellos, excepto entre el tercer y cuarto ventrículo y el tercero y el volumen ventricular derecho. Los estadísticos del modelo lineal multivariante aplicado mostraron que sólo eran significativos en función del sexo y del tipo de cráneo. No se encontraron diferencias significativas con respecto al sexo en ningún volumen, excepto en el tercer ventrículo (p= 0,01). Lo mismo ocurrió por tipo de cráneo (p= 0,005). Conclusiones: El método de morfometría del sistema ventricular encefálico a partir de imágenes de Tomografía Computarizada / Segmentación por homogeneidad, permitió cuantificar los cambios volumétricos cerebrales asociados al envejecimiento normal y puede ser utilizado como biomarcador de la relación entre la estructura cerebral y las funciones cognitivas(AU)


Introduction: Due to the need for an early diagnosis of neurodegenerative disorders, attempts have been made to harmonize diagnostic criteria using morphometric methods based on neuroimaging techniques, but conclusive results have not yet been obtained. Objective: To determine the ventricular volume due to its wide use as a marker of cerebral atrophy and to identify the effect of sex on these structures, according to the type of skull, estimated from multislice computed tomography imaging techniques. Methods: An observational and descriptive study was developed in 30 subjects with normal neurocognitive functions and neuropsychiatric examination, aged between 45 and 54 years, who underwent a simple multislice CT scan of the skull. An image segmentation method based on homogeneity was used. Results: The ventricular volumes showed a significant and positive correlation between them, except between the third and fourth ventricles and the third and the right ventricular volume. The statistics in the multivariate linear model applied showed that they were only significant in terms of sex and type of skull. No significant differences were found regarding sex in any volume except in the third ventricle (p= 0.01). The same occurred by type of skull (p= 0.005). Conclusions: The morphometry method of the encephalic ventricular system from Computed Tomography images / Segmentation by homogeneity, allowed to quantify the cerebral volumetric changes associated with normal aging and can be used as a biomarker of the relationship between brain structure and cognitive functions(AU)


Assuntos
Humanos , Pessoa de Meia-Idade , Ventrículos Cerebrais/diagnóstico por imagem , Antropometria/métodos , Titulometria/métodos , Cognição , Tomografia Computadorizada Multidetectores/métodos , Neuroimagem/métodos , Epidemiologia Descritiva , Estudo Observacional
5.
Arq. ciências saúde UNIPAR ; 26(3): 1044-1052, set-dez. 2022.
Artigo em Português | LILACS | ID: biblio-1414341

RESUMO

As soluções volumétricas são rotineiramente utilizadas nos laboratórios, principalmente nos processos de síntese de produtos e nas análises quantitativas de matéria-prima e/ou produto acabado, entretanto poucos são os estudos que abordam a estabilidade destas soluções. Considerando que a qualidade das soluções volumétricas pode afetar os procedimentos de análises químicas e consequentemente induzir a erros, e ainda que, a Farmacopeia Brasileira (2010) não cita tempo máximo de utilização dessas soluções padronizadas, a avaliação da estabilidade das mesmas é importante. Sendo assim, o objetivo do trabalho foi avaliar a estabilidadede 10 soluções volumétricas, empregadas rotineiramente em laboratórios de análises químicas, com o intuito de estabelecer o período que essas soluções permanecem estáveis, isto é, sem sofrer alteração na concentração. As metodologias de preparo e padronização das soluções volumétricas seguiram os métodos descritos na Farmacopeia Brasileira (2010), sendo as mesmas padronizadas no momento do preparo e a cada 20 dias, por um período de 180 dias. As soluções contendo ácidos e bases, bem como as soluções de iodato de potássio e nitrato de prata, permaneceram constantes durante o período de análises. As soluções de EDTA, iodo, nitrito de sódio, permanganato de potássio e tiossulfato de sódio apresentaram estabilidade inferior a 180 dias, tornando necessária a realização de padronização periódica. As soluções volumétricas utilizadas nos laboratórios apresentam diferentes estabilidades, o que ressalta a importância da determinação do período que as mesmas se mantêmcom as concentrações estáveis, evitando possíveis alterações de resultados nas análises químicas.


Volumetric solutions are routinely used in laboratories, mainly in product synthesis processes and in quantitative analyzes of raw materials and/or finished products, however there are few studies that address the stability of these solutions. Considering that the quality of volumetric solutions can affect chemical analysis procedures and consequently induce errors, and even though the Brazilian Pharmacopoeia (2010) does not mention the maximum time for using these standardized solutions, the evaluation of their stability is important. Therefore, the aim of this work was to evaluate the stability of 10 volumetric solutions, routinely used in chemical analysis laboratories, in order to establish the period that these solutions remain stable without changing their concentrations. The methodologies for preparing and standardizing the volumetric solutions followed the methods described in the Brazilian Pharmacopoeia (2010), being standardized at the time of preparation and every 20 days, for a period of 180 days. Solutions containing acids and bases, as well as potassium iodate and silver nitrate solutions, were stable during the analysis period. The solutions of EDTA, iodine, sodium nitrite, potassium permanganate and sodium thiosulfate showed stability less than 180 days, making it necessary to carry out periodic standardization of these solutions. The volumetric solutions used in the laboratories have different stabilities, which highlights the importance of determining the period in which they remain stable, avoiding possible changes in results in chemical analyzes.


Las soluciones volumétricas se utilizan de forma rutinaria en los laboratorios, principalmente en los procesos de síntesis de productos y en el análisis cuantitativo de materias primas y/o productos acabados. Sin embargo, existen pocos estudios que aborden la estabilidad de estas soluciones. Considerando que la calidad de las soluciones volumétricas puede afectar los procedimientos de análisis químico y consecuentemente inducir a errores, y también que, la Farmacopea Brasileña (2010) no menciona el tiempo máximo de uso de estas soluciones estandarizadas, la evaluación de su estabilidad es importante. Así, el objetivo del trabajo fue evaluar la estabilidad de 10 soluciones volumétricas, utilizadas rutinariamente en los laboratorios de análisis químico, con el fin de establecer el período en que estas soluciones permanecen estables, es decir, sin sufrir alteraciones en la concentración. Las metodologías de preparación y estandarización de las soluciones volumétricas siguieron los métodos descritos en la Farmacopea Brasileña (2010), siendo las mismas estandarizadas en el momento de la preparación y cada 20 días, por un período de 180 días. Las soluciones que contienen ácidos y bases, así como las soluciones de yodato de potasio y nitrato de plata, permanecieron constantes durante el periodo de análisis. Las soluciones de EDTA, yodo, nitrito de sodio, permanganato de potasio y tiosulfato de sodio fueron estables durante menos de 180 días, por lo que fue necesario realizar estandarizaciones periódicas. Las soluciones volumétricas utilizadas en los laboratorios presentan diferentes estabilidades, lo que pone de manifiesto la importancia de determinar el periodo que permanecen con concentraciones estables, evitando posibles cambios en los resultados en los análisis químicos.


Assuntos
Titulometria , Reagentes de Laboratório/análise , Laboratórios Clínicos , Periodicidade , Permanganato de Potássio/análise , Padrões de Referência , Nitrato de Prata/análise , Nitrito de Sódio/análise , Tiossulfatos/análise , Farmacopeia Brasileira , Iodatos/análise
6.
Rev. Inst. Adolfo Lutz (Online) ; 81: e36985, mar.1, 2022. tab, graf
Artigo em Português | LILACS, CONASS, Coleciona SUS (Brasil), SES-SP, VETINDEX, SESSP-ACVSES, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: biblio-1396577

RESUMO

Os suplementos à base de vitamina C são amplamente consumidos pela população, evidenciando a importância da fiscalização desses produtos. Em julho de 2018, a ANVISA (Agência Nacional de Vigilância Sanitária) publicou as novas regulamentações sobre suplementos alimentares, estabelecendo-se o prazo de 60 meses para as empresas se adequarem a essas normas. O presente trabalho teve como objetivo determinar os teores de vitamina C, comparar os valores analisados com os declarados na informação nutricional e avaliar os dizeres de rotulagem em produtos à base dessa vitamina. Os teores de vitamina C foram determinados por titulação potencio métrica e as análises de rotulagem foram realizadas com base nas legislações da ANVISA em doze amostras de suplementos colhidos pelas Vigilâncias Sanitárias do Estado de São Paulo. Os teores de vitamina C avaliados estavam de acordo com os declarados na informação nutricional do rótulo, com exceção de uma amostra que apresentou teor abaixo do valor declarado. Em relação aos dizeres de rotulagem, sete amostras (58%) apresentaram um ou mais itens em desacordo com a legislação, mostrando a necessidade de monitoramento constante desse tipo de produto. O trabalho representa um estudo preliminar de avaliação dos suplementos no período de adequação às novas regulamentações (AU).


Vitamin C-based supplements are widely consumed by the population, highlighting the importance of monitoring these products. In July 2018, the ANVISA (National Health Surveillance Agency) published new regulations for dietary supplements,setting a 60 months deadline for companies to comply with these standards.The objective of the present work was to evaluate the contents of vitamin C, and compare the analyzed/real values with those reported on the nutrition facts label, and to evaluate the labeling of vitamin supplements. Vitamin C contents were determined by potentiometric titration, and labeling analysis were performed based on ANVISA legislation in twelve samples of supplements collected by the Sanitary Surveillance of the State of São Paulo.The contents of vitamin C were in accordance with those declared in the nutritional information on the label, with the exception of one sample that presented content below the declared value. Regarding the labeling analysis, seven samples (58%) presented one or more items in disagreement with the legislation, showing the need for constant monitoring of this type of product.The work represents a preliminary study to evaluate the supplements in the adequacy period of new regulations (AU).


Assuntos
Rotulagem de Produtos , Ácido Ascórbico , Vitaminas , Titulometria , Suplementos Nutricionais , Legislação como Assunto
7.
Anal Biochem ; 639: 114521, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34906540

RESUMO

NMR is a powerful tool for characterizing intermolecular interactions at atomic resolution. However, the nature of the complex interactions of membrane-binding proteins makes it difficult to elucidate the interaction mechanisms. Here, we demonstrated that structural and thermodynamic analyses using solution NMR spectroscopy and isothermal titration calorimetry (ITC) can clearly detect a specific interaction between the pleckstrin homology (PH) domain of ceramide transport protein (CERT) and phosphatidylinositol 4-monophosphate (PI4P) embedded in the lipid nanodisc, and distinguish the specific interaction from nonspecific interactions with the bulk surface of the lipid nanodisc. This NMR-ITC hybrid strategy provides detailed characterization of protein-lipid membrane interactions.


Assuntos
Bicamadas Lipídicas/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Calorimetria/instrumentação , Calorimetria/métodos , Humanos , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética/instrumentação , Simulação de Dinâmica Molecular , Nanoestruturas/química , Fosfatos de Fosfatidilinositol/química , Ligação Proteica , Domínios Proteicos , Proteínas Serina-Treonina Quinases/química , Titulometria/instrumentação , Titulometria/métodos
9.
Int J Mol Sci ; 22(21)2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34769476

RESUMO

A NASICON-based Na3V2(PO4)2F3 (NVPF) cathode material is reported herein as a potential symmetric cell electrode material. The symmetric cell was active from 0 to 3.5 V and showed a capacity of 85 mAh/g at 0.1 C. With cycling, the NVPF symmetric cell showed a very long and stable cycle life, having a capacity retention of 61% after 1000 cycles at 1 C. The diffusion coefficient calculated from cyclic voltammetry (CV) and the galvanostatic intermittent titration technique (GITT) was found to be ~10-9-10-11, suggesting a smooth diffusion of Na+ in the NVPF symmetric cell. The electrochemical impedance spectroscopy (EIS) carried out during cycling showed increases in bulk resistance, solid electrolyte interphase (SEI) resistance, and charge transfer resistance with the number of cycles, explaining the origin of capacity fade in the NVPF symmetric cell. Finally, the postmortem analysis of the symmetric cell after 1000 cycles at a 1 C rate indicated that the intercalation/de-intercalation of sodium into/from the host structure occurred without any major structural destabilization in both the cathode and anode. However, there was slight distortion in the cathode structure observed, which resulted in capacity loss of the symmetric cell. The promising electrochemical performance of NVPF in the symmetric cell makes it attractive for developing long-life and cost-effective batteries.


Assuntos
Fontes de Energia Elétrica , Técnicas Eletroquímicas , Fluoretos/química , Fosfatos/química , Compostos de Vanádio/química , Técnicas Biossensoriais/instrumentação , Espectroscopia Dielétrica , Difusão , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Teste de Materiais/métodos , Reciclagem , Fluoreto de Sódio/química , Titulometria/métodos
10.
J Inorg Biochem ; 225: 111593, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555598

RESUMO

In this study on model compounds for the resting oxidized state of the iron­copper binuclear center in cytochrome c oxidase (CcO), we describe the synthesis of a new µ-oxo-heme/Cu complex, [(TPP)FeIII-O-CuII(tmpa)][B(C6F5)4] (2) {TPP: tetraphenyl porphyrinate(2-); TMPA: tris(2-pyridylmethylamine)}, as well as two protonation events for three µ-oxo-heme/Cu complexes with varying peripheral substituents on the heme site. The addition of increasing amounts of strong acid to these µ-oxo-heme/Cu systems successively led to the generation of the corresponding µ-hydroxo, µ-aquo, and the dissociated complexes. The heme/Cu assemblies bridged through a water ligand are reported here for the first time and the 1H NMR and 19F NMR spectral properties are consistent with antiferromagnetically coupled high-spin iron(III) and copper(II) centers. By titration using a series of protonated amines, the pKa values for the corresponding µ-hydroxo-heme/Cu species (i.e., the first protonation event) have been reported and compared with the pKa ranges previously estimated for related systems. These synthetic systems may represent structural models for the oxidized FeIII-X-CuII resting state, or turnover intermediates and can be employed to clarify the nature of proton/electron transfer events in CcO. SYNOPSIS: The resting oxidized state of the cytochrome c oxidase active site contains an Fea3-OHx-CuB moiety. Here, we investigated two successive protonation events, for a series of µ-oxo-heme/Cu assemblies and reported the pKa values for the first protonation event. The µ-aquo-heme/Cu complexes described here are the first examples of such systems.


Assuntos
Complexos de Coordenação/química , Heme/análogos & derivados , Aminas/química , Domínio Catalítico , Complexos de Coordenação/síntese química , Cobre/química , Complexo IV da Cadeia de Transporte de Elétrons/química , Modelos Químicos , Estrutura Molecular , Prótons , Titulometria
11.
Odovtos (En línea) ; 23(2)ago. 2021.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1386535

RESUMO

ABSTRACT: Cone-beam computed tomography (CBCT) is a 3D imaging technique widely used in maxillofacial diagnosis. The grayscale value (GSV) is a number that represents the amount of attenuation of the X-ray beam by the material contained in each voxel or structural unit of the tomographic volume. Similarly, in computed tomography (CT) used in medical radiology, the attenuation values are standardized in the Hounsfield Unit (HU) scale. Although GSV may have interesting potential applications in maxillofacial diagnosis, it is essential to know that HU differ from GSV. The latter are susceptible to multiple technical factors during the tomographic acquisition, so their value can vary among different CBCT scanners or when technical parameters are modified. Hence, GSV should not be extrapolated between different CBCT machines, and their use should be cautious while more investigation is available considering various equipment and acquisition protocols.


RESUMEN: La tomografía computarizada de haz cónico (CBCT, por sus siglas en inglés) es una técnica de imagen 3D ampliamente usada en diagnóstico maxilofacial. El valor de densidad en la escala de grises (DEG) es una cifra que corresponde al grado de atenuación de los rayos x del material representado en cada vóxel o unidad estructural de la tomografía. De forma similar, en los sistema de tomografía computarizada de uso médico (CT) el valor de atenuación está estandarizado en las Unidades Hounsfield (UH). Aunque los valores de DEG pueden tener interesantes usos potenciales en el apoyo de diagnóstico en el área dentoalveolar, es importante conocer que los valores UH no son los mismos a los valores DEG, y que los valores de DEG son susceptibles a múltiples factores técnicos durante la adquisición de la tomografía, por lo que se pueden obtener resultados distintos entre equipos y al variar parámetros técnicos en las tomas. Por lo tanto sus valores no deben extrapolarse entre equipos y su uso debe ser cauteloso mientras se realiza mayor investigación específica para cada equipo y para cada protocolo de adquisición.


Assuntos
Titulometria , Tomografia Computadorizada de Feixe Cônico/métodos
12.
Transfusion ; 61(6): 1749-1756, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33797101

RESUMO

BACKGROUND: Antenatal titration testing is traditionally performed using a manual tube test. Tube testing has limitations; it is a manual, time-consuming method with wide interobserver variability. Gel-based testing is an attractive alternative because it is more precise and can be automated. This study's objective was to summarize the published literature that assessed the relationship between titrations performed by tube and gel for anti-D alloimmunized pregnancies. STUDY DESIGN AND METHODS: A comprehensive literature search was performed. Articles were selected if research was original and compared at least five pairs of anti-D titration tests performed by gel and tube. Differences in the number of dilutions between gel and tube methods were compared overall by study and cell type using linear models. RESULTS: A total of 512 articles were identified; eight were included, and titer data from 384 tube and gel pairs were abstracted. The median anti-D titer in tube was 8 (range 0-2048) and by gel was 64 (range 0-4096). Anti-D gel titration results were 2.1 (95% CI; 1-3.3) additional dilutions greater than in tube. Most studies utilized double-dose reagent cells for testing. At a tube titer of 16, the sensitivity and specificity of gel titrations is maximal (91% and 94% respectively) at a gel titer of 64. CONCLUSION: Overall, titrations performed by gel were two dilutions higher than the corresponding tube titer. For titrations, double-dose reagent cells should be considered to standardize practice. A rigorous prospective study is needed to compare tube titrations with gel titrations using a standardized process.


Assuntos
Imunoglobulina rho(D)/análise , Eritroblastose Fetal/diagnóstico , Feminino , Humanos , Imunoensaio/métodos , Isoanticorpos/análise , Gravidez , Diagnóstico Pré-Natal/métodos , Titulometria/métodos
13.
Clin Exp Nephrol ; 25(9): 963-969, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33885995

RESUMO

BACKGROUND: Regional citrate anti-coagulation (RCA) is the recommended anti-coagulation for continuous renal replacement therapy (CRRT). Citrated replacement fluids provide convenience but may compromise effluent delivery when adjusted to maintain circuit ionised calcium levels (circuit-iCa). This study aims to evaluate the effect of RCA titration on the delivered CRRT effluent dose. METHODS: This prospective observational study evaluated patients on RCA-CRRT in continuous veno-venous hemodiafiltration mode. Citrated replacement fluid was titrated to target circuit-iCa 0.26-0.40 mmol/L. Patients were then stratified into 'reduced-dose' who required citrate down-titration and 'stable-dose' who did not. RESULTS: Data from 200 RCA-CRRT sessions were collected. The reduced-dose RCA group (n = 114) had higher median initial citrate dose (3.00 vs 2.50; P < 0.001) but lower time-averaged dose (2.49 vs 2.60; P < 0.001). In addition, median prescribed effluent dose was 33.3 mL/kg/h (28.6-39.2) but median delivered effluent dose was significantly lower at 29.9 mL/kg/h (25.4-36.9; P < 0.001). Mortality was higher in the reduced-dose RCA group (39.5% vs 25.6%; P = 0.022) and in patients with delivered-to-prescribed effluent dose ratio of < 0.9 vs ≥ 0.9 (51.3% vs 29.2%; P = 0.014). CONCLUSION: RCA titration can significantly impact delivered CRRT effluent dose. Measures should be taken to address the CRRT dose deficit and prevent poor outcomes due to inadequate dialysis.


Assuntos
Anticoagulantes/administração & dosagem , Ácido Cítrico/administração & dosagem , Terapia de Substituição Renal Contínua , Insuficiência Renal/terapia , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Cálcio/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Titulometria
14.
Acta Diabetol ; 58(6): 789-796, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33586058

RESUMO

AIMS: The Italian Titration Approach Study (ITAS) demonstrated comparable HbA1c reductions and similarly low hypoglycaemia risk at 6 months in poorly controlled, insulin-naïve adults with T2DM who initiated self- or physician-titrated insulin glargine 300 U/mL (Gla-300) in the absence of sulphonylurea/glinide. The association of patient characteristics with glycaemic and hypoglycaemic outcomes was assessed. METHODS: This post hoc analysis investigated whether baseline patient characteristics and previous antihyperglycaemic drugs were associated with HbA1c change and hypoglycaemia risk in patient- versus physician-managed Gla-300 titration. RESULTS: HbA1c change, incidence of hypoglycaemia (any type) and nocturnal rates were comparable between patient- and physician-managed arms in all subgroups. Hypoglycaemia rates across subgroups (0.03 to 3.52 events per patient-year) were generally as low as observed in the full ITAS population. Small increases in rates of 00:00-pre-breakfast and anytime hypoglycaemia were observed in the ≤ 10-year diabetes duration subgroup in the patient- versus physician-managed arm (heterogeneity of effect; p < 0.05). CONCLUSIONS: Comparably fair glycaemic control and similarly low hypoglycaemia risk were achieved in almost all patient subgroups with patient- versus physician-led Gla-300 titration. These results reinforce efficacy and safety of Gla-300 self-titration across a range of phenotypes of insulin-naïve people with T2DM. CLINICAL TRIAL REGISTRATION: EudraCT 2015-001167-39.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Cálculos da Dosagem de Medicamento , Insulina Glargina/administração & dosagem , Médicos , Autogestão , Adulto , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Seguimentos , Controle Glicêmico/métodos , Controle Glicêmico/normas , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/epidemiologia , Incidência , Insulina Glargina/efeitos adversos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Relações Médico-Paciente , Médicos/normas , Médicos/estatística & dados numéricos , Estudos Retrospectivos , Autogestão/estatística & dados numéricos , Titulometria/métodos , Titulometria/normas
15.
Mass Spectrom Rev ; 40(3): 177-200, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32400038

RESUMO

Within the past decade protein footprinting in conjunction with mass spectrometry has become a powerful and versatile means to unravel the higher order structure of proteins. Footprinting-based approaches has demonstrated the capacity to inform on interaction sites and dynamic regions that participate in conformational changes. These findings when set in a biological perspective inform on protein folding/unfolding, protein-protein interactions, and protein-ligand interactions. In this review, we will look at the contribution of Dr. Michael L. Gross to protein footprinting approaches such as hydrogen deuterium exchange mass spectrometry and hydroxyl radical protein footprinting. This review details the development of novel footprinting methods as well as their applications to study higher order protein structure. © 2020 The Authors. Mass Spectrometry Reviews published by John Wiley & Sons Ltd. Mass Spec Rev.


Assuntos
Espectrometria de Massas/métodos , Fotoquímica/métodos , Pegadas de Proteínas/métodos , Proteínas/química , Medição da Troca de Deutério , Mapeamento de Epitopos/métodos , Concentração de Íons de Hidrogênio , Ligantes , Soluções , Titulometria/métodos
16.
Braz. dent. sci ; 24(1): 1-6, 2021. tab, ilus
Artigo em Inglês | BBO - odontologia (Brasil), LILACS | ID: biblio-1145536

RESUMO

Objective: Forensic dentistry has used some methods for the human identification process. However, there is a need to study characteristics that are able to perform identification more specifically, increasing accuracy. Considering the role of dental arch assessment in prediction of gender and ethnicity, the purpose of this study was to assess the volume of pulp chamber as a mean to obtain new forensic evidence. Material and methods: For this task, 1.190 cone beam computed tomography (CBCT) images were retrospectively selected and subdivided according to the population number, gender, age and ethnicity. All DICOM files were imported to the open-source software ITK-SNAP®(http://www.itksnap.org/pmwiki/pmwiki.php). The segmentation process was performed in all pulp chamber aiming to obtain pulp tissue ́s volume. Results: As a result, the pulp chamber volume of mandibular canine teeth showed to be larger in white population than in non-white (P-value = 0.003) and in male individuals in comparison with female (P-value = 0.038). Conclusion: These results, however, must be confirmed by future studies with a larger sample size and by the assessment of other variables, including texture analysis and density of dental tissues. (AU)


Objetivo: A odontologia forense tem usado alguns métodos para o processo de identificação humana. Porém, há a necessidade de estudar características que consigam de forma mais específica realizar a identificação aumentando a precisão. Considerando o papel da avaliação da arcada dentária na predição de gênero e etnia, o objetivo deste estudo foi avaliar o volume da câmara pulpar mandibular como meio de obtenção de novas evidências periciais. Material e métodos: Foram selecionadas 1.190 imagens de tomografia computadorizada de feixe cônico (TCFC) e subdivididas de acordo com o número da população, sexo, idade e etnia. Todos os arquivos em formato DICOM foram importados para o software de código aberto ITK-SNAP® (http://www.itksnap.org/pmwiki/pmwiki.php) onde o processo de segmentação foi realizado em todas as câmaras pulpares visando a obtenção da volumetria. Resultados: Como resultado, o volume da câmara pulpar dos caninos inferiores mostrou-se maior na população branca do que na não branca (P-valor = 0,003), no sexo masculino em comparação ao feminino (P-valor = 0,038). Conclusão: Esses resultados, entretanto, devem ser confirmados por estudos futuros com maior tamanho amostral e pela avaliação de outras variáveis, incluindo análise de textura e densidade dos tecidos dentários. (AU)


Assuntos
Humanos , Etnicidade , Titulometria , Cavidade Pulpar , Tomografia Computadorizada de Feixe Cônico , Odontologia Legal , Identidade de Gênero
17.
Molecules ; 25(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887468

RESUMO

Vaccination could be a promising alternative warfare against drug addiction and abuse. For this purpose, so-called haptens can be used. These molecules alone do not induce the activation of the immune system, this occurs only when they are attached to an immunogenic carrier protein. Hence obtaining a free amino or carboxylic group during the structural transformation is an important part of the synthesis. Namely, these groups can be used to form the requisite peptide bond between the hapten and the carrier protein. Focusing on this basic principle, six nor-morphine compounds were treated with ethyl acrylate and ethyl bromoacetate, while the prepared esters were hydrolyzed to obtain the N-carboxymethyl- and N-carboxyethyl-normorphine derivatives which are considered as potential haptens. The next step was the coupling phase with glycine ethyl ester, but the reactions did not work or the work-up process was not accomplishable. As an alternative route, the normorphine-compounds were N-alkylated with N-(chloroacetyl)glycine ethyl ester. These products were hydrolyzed in alkaline media and after the work-up process all of the derivatives contained the free carboxylic group of the glycine side chain. The acid-base properties of these molecules are characterized in detail. In the N-carboxyalkyl derivatives, the basicity of the amino and phenolate site is within an order of magnitude. In the glycine derivatives the basicity of the amino group is significantly decreased compared to the parent compounds (i.e., morphine, oxymorphone) because of the electron withdrawing amide group. The protonation state of the carboxylate group significantly influences the basicity of the amino group. All of the glycine ester and the glycine carboxylic acid derivatives are currently under biological tests.


Assuntos
Haptenos/química , Morfina/química , Prótons , Analgésicos Opioides/química , Desmetilação , Ésteres/síntese química , Ésteres/química , Titulometria
18.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;54(3): 285-292, set. 2020. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-1130603

RESUMO

Los posibles efectos adversos que se producen en transfusiones incompatibles ABO son un riesgo latente en el uso de concentrados de plaquetas grupo O, por lo que la titulación de hemolisinas anti-A/B constituye una de las estrategias para su prevención. El objetivo de este estudio fue determinar la frecuencia de títulos de hemolisinas de isotipos IgG e IgM anti-A/B en donantes de sangre. Se trató de un estudio descriptivo, transversal y aleatorio simple con un tamaño muestral de 308 muestras. Se aplicó la metodología en tubo, gel salino y anti-inmunoglobulina IgG y, mediante soluciones seriadas, se evidenció el título. Adicionalmente, se realizó una encuesta sobre los posibles factores de riesgo para el aumento de estos títulos. Se aplicó estadística descriptiva mediante el uso del software informático SPSS versión 22.0 y la relación entre variables independientes a través del análisis estadístico de Chi-cuadrado y, para establecer la concordancia de las lecturas visuales de las tarjetas de gel, se aplicó el índice kappa. Se determinó la existencia de hemolisinas de isotipo IgG e IgM anti-A/B de títulos superiores a 1/64. Existió una relación estadísticamente significativa entre embarazos y títulos de IgG anti-A/B >1/128 y el aumento de hemolisinas de isotipo IgM y la ingesta de probióticos. Los resultados demostraron la necesidad de implementar la titulación de hemolisinas previo a la transfusión de concentrados plaquetarios no isogrupo, por lo que se recomienda una investigación de riesgo-beneficio y el seguimiento de pacientes con transfusiones de concentrados plaquetarios incompatibles ABO.


The possible adverse effects that occur in incompatible ABO transfusions are a latent risk in the use of group O platelet concentrates, so the titration of anti-A/B hemolysins is one of the strategies for its prevention. The objective of this study was to determine the frequency of hemolysins titers IgG and IgM anti-A/B isotypes in blood donours. It was a simple randomized descriptive cross-sectional study with a sample size of 308 samples. The methodology was applied in tube, saline gel and anti-IgG anti-immunoglobulin and by means of serial solutions the title was verified. Additionally, a survey was conducted on the possible risk factors for the increase in securities. Descriptive statistics were used through the application of the SPSS version 22.0 software and the relationship between independent variables through the Chi-square statistical analysis and the kappa index was applied to match the visual readings of the gel cards. The existence of IgG and IgM anti-A/B isotype hemolysins of titers greater than 1/64 was determined. There was a statistically significant relationship between pregnancies and anti-A/B IgG titres>1/128; and the increase in IgM isotype hemolysins and probiotic intake. The results demonstrate the need to implement hemolysin titration prior to transfusion of non-isogroup platelet concentrates, so a risk-benefit investigation and follow-up of patients with transfusions of ABO incompatible platelet concentrates is recommended.


Os possíveis efeitos adversos que ocorrem em transfusões incompatíveis ABO são um risco latente no uso de concentrados de plaquetas do grupo O, portanto a titulação de hemolisinas anti-A/B é uma das estratégias para sua prevenção. O objetivo deste estudo foi determinar a frequência de títulos de hemolisinas de isotipos IgG e IgM anti-A/B em doadores de sangue. Trata-se de um estudo descritivo transversal aleatório simples, com tamanho de amostra de 308 amostras. A metodologia foi aplicada em tubo, gel salino e anti-imunoglobulina IgG e utilizando soluções em série, o título foi verificado. Além disso, foi realizada uma pesquisa sobre os possíveis fatores de risco para o aumento destes títulos. A estatística descritiva foi utilizada através da aplicação do software informático SPSS versão 22.0 e a relação entre variáveis independentes por meio da análise estatística do qui-quadrado e, para estabelecer a concordância com as leituras visuais dos cartões de gel, o índice kappa foi aplicado. Foi determinada a existência de hemolisinas de isotipo IgG e IgM anti-A/B de títulos maiores que 1/64. Existiu uma relação estatisticamente significante entre gestações e títulos de IgG anti-A/B>1/128; e o aumento de hemolisinas do isotipo IgM e a ingestão de probióticos. Os resultados demonstram a necessidade de implementar a titulação da hemolisina antes da transfusão de concentrados de plaquetas não isogrupo, por isso, recomenda-se uma investigação de risco-benefício e acompanhamento de pacientes com transfusões de concentrados de plaquetas incompatíveis com ABO.


Assuntos
Humanos , Masculino , Feminino , Plaquetas , Isotipos de Imunoglobulinas/sangue , Software , Imunoglobulina G , Imunoglobulina M , Imunoglobulinas , Fatores de Risco , Probióticos , Proteínas Hemolisinas , Voluntários , Sangue , Doadores de Sangue , Risco , Morbidade , Titulometria , Assistência ao Convalescente , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Prevenção de Doenças
20.
Methods Mol Biol ; 2142: 9-22, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32367355

RESUMO

Zika virus (ZIKV) is an important pathogen transmitted to humans by the mosquito vector Aedes aegypti. ZIKV is able to infect several tissues and organs and, importantly, has been associated with microcephaly and central nervous system abnormalities in fetuses and newborn babies of mothers exposed to ZIKV during pregnancy, as well as neurological diseases such as Guillain-Barré syndrome in adults. There is currently no vaccine or drug licensed to prevent or treat ZIKV infections. The use of ZIKV isolation in disease diagnosis has been largely replaced by new techniques. However, virus isolation is still considered as a gold standard for the detection of ZIKV and is usually performed in research and reference laboratories for characterization, sequencing, and a variety of research experiments including pathogenesis, drug susceptibility, and vaccine efficacy. The experimental procedures presented here describe the most common techniques used for ZIKV isolation, propagation, purification, and quantification.


Assuntos
Titulometria/métodos , Virologia/métodos , Infecção por Zika virus/virologia , Zika virus/crescimento & desenvolvimento , Zika virus/isolamento & purificação , Animais , Chlorocebus aethiops , Células Vero , Ensaio de Placa Viral/métodos , Infecção por Zika virus/patologia
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