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China Journal of Chinese Materia Medica ; (24): 4328-4336, 2023.
Article in Chinese | WPRIM | ID: wpr-1008687


This Fructus,study including and aimed to construct a rapid and nondestructive detection flavonoid,model betaine,for and of the content vitamin of(Vit four four quality C).index components Lycium barbarum polysaccharide,of inL ycii rawma total and C Hyperspectral data quantitative of terials modelswere powder developed Lycii using Fructus partial were squares effects collected,regression raw based LSR),on the support content vector the above components,the forest least(P regression compared,(SVR),the and effects random three regression(RFR)were algorithms.also The Four spectral predictive commonly data of the materialsand powder were were applied and of spectral quantitative for models reduction.compared.used were pre-processing screened methods feature to successive pre-process projection the raw algorithm data(SPA),noise competitive Thepre-processed for bands using adaptive reweigh ted sampling howed(CARS),the and maximal effects relevance based and raw minimal materials redundancy and(MRMR)were algorithms Following to optimize multiplicative the models.scatter The correction Based resultss(MS that prediction SPA on feature the powder prediction similar.PLSR C)denoising sproposed and integrated for model,screening the the coefficient bands,determination the effect(R_C~2)of(MSC-SPA-PLSR)coefficient was optimal.of on(R_P~2)thi of of calibration flavonoid,and and of all determination greater prediction0.83,L.barbarum inconte nt prediction of polysaccharide,total mean betaine,of Vit C were than smallest In the compared study,root with mean other prediction content squareserror models of the calibration(RMSEC)residual and deviation root squares was error2.46,prediction2.58,(RMSEP)and were the,and prediction(RPD)2.50,developed3.58,achieve respectively.rapid this the the quality mod el(MSC-SPA-PLSR)fourcomponents based Fructus,on hyperspectral which technology was approach to rapid and effective detection detection of the of Lycii in Lycii provided a new to the and nondestructive of of Fructus.

Spectroscopy, Near-Infrared/methods , Betaine , Powders , Least-Squares Analysis , Algorithms , Flavonoids
Arch. argent. pediatr ; 120(2): 129-135, abril 2022. ilus
Article in English, Spanish | LILACS, BINACIS | ID: biblio-1363811


La espectroscopia cercana infrarroja (NIRS, por su sigla en inglés), es una técnica óptica no invasiva y no ionizante utilizada para medir la oxigenación tisular regional a través de sensores transcutáneos. En los últimos años, han aumentado de manera exponencial las publicaciones sobre este tema; esto refleja el creciente interés de investigadores y clínicos por la utilización de esta nueva tecnología y los beneficios que podría ofrecerles a los pacientes pediátricos. El objetivo de esta revisión es dar a conocer el funcionamiento y las posibles aplicaciones de la saturación regional medida por NIRS, así como los desafíos en el futuro.

Near infrared spectroscopy (NIRS) is a non-invasive optical technique for the evaluation of regional tissue oxygenation using transcutaneous detectors. In recent years, publications about this topic have increased exponentially; this reflects the growing interest among investigators and clinicians about this new technology and its potential benefits for pediatric patients. The objective of this review is to know the functioning and potential uses of regional saturation measured by NIRS and establish future challenges.

Humans , Child , Pediatrics , Hemodynamic Monitoring , Oxygen , Oximetry/methods , Spectroscopy, Near-Infrared/methods
China Journal of Chinese Materia Medica ; (24): 1293-1299, 2022.
Article in Chinese | WPRIM | ID: wpr-928055


This study established a method for rapid quantification of terpene lactone, bilobalide, ginkgolide C, ginkgolide A and ginkgolide B in the chromatographic process of Ginkgo Folium based on near infrared spectroscopy(NIRS). The effects of competitive adaptive reweighting sampling(CARS), random frog(RF), and synergy interval partial least squares(siPLS) on the performance of partial least squares regression(PLSR) model were compared to the reference values measured by HPLC. Among them, the correlation coefficients of prediction(Rp) of validation sets of terpene lactone, bilobalide, and ginkgolide C were all higher than 0.98, and the relative standard errors of prediction(RSEPs) were 5.87%, 6.90% and 6.63%, respectively. Aiming at ginkgolide A and ginkgolide B with relatively low content, the genetic algorithm joint extreme learning machine(GA-ELM) was used to establish the optimized quantitative analysis model. Compared with CARS-PLSR model, the CARS-GA-ELM models of ginkgolide A and ginkgolide B exhibited a reduction in RSEP from 15.65% to 8.52% and from 21.28% to 10.84%, respectively, which met the needs of quantitative ana-lysis. It has been proved that NIRS can be used for the rapid detection of various lactone components in the chromatographic process of Ginkgo Folium.

Chromatography, High Pressure Liquid , Ginkgo biloba , Lactones/analysis , Least-Squares Analysis , Spectroscopy, Near-Infrared/methods
Chinese Journal of Contemporary Pediatrics ; (12): 620-625, 2022.
Article in Chinese | WPRIM | ID: wpr-939638


OBJECTIVES@#To investigate the incidence and mortality of gastrointestinal dysfunction in children with sepsis, the application of near-infrared spectroscopy (NIRS) in monitoring mesenteric regional tissue oxygen saturation (rSO2), and the association between rSO2 and gastrointestinal dysfunction.@*METHODS@#In this prospective study, 79 children with sepsis in the pediatric intensive care unit (sepsis group) and 40 children who underwent physical examination in the Department of Child Healthcare (healthy control group) from January to December, 2021 were enrolled as subjects. The related medical data were collected, including general information on admission and at discharge, treatment during hospitalization, and laboratory examination results. NIRS was used to measure mesenteric rSO2. Clinical characteristics were compared between the patients with and without gastrointestinal dysfunction.@*RESULTS@#For the 79 children with sepsis, the incidence rate of gastrointestinal dysfunction was 49% (39/79), and the mortality rate of the children with gastrointestinal dysfunction was 26% (10/39). The children with gastrointestinal dysfunction had a longer duration of mechanical ventilation and a higher 28-day mortality rate (P<0.05). The children with gastrointestinal dysfunction had a significantly lower median rSO2 (64%) than the children without gastrointestinal dysfunction (72%) and the healthy control group (78%) (P<0.05).@*CONCLUSIONS@#There are high incidence and mortality rates of gastrointestinal dysfunction in children with sepsis, and the reduction in rSO2 may be associated with the development of gastrointestinal dysfunction.

Child , Humans , Gastrointestinal Diseases/etiology , Intensive Care Units, Pediatric , Oxygen , Prospective Studies , Sepsis/complications , Spectroscopy, Near-Infrared/methods
Journal of Biomedical Engineering ; (6): 228-236, 2022.
Article in Chinese | WPRIM | ID: wpr-928218


Working memory is an important foundation for advanced cognitive function. The paper combines the spatiotemporal advantages of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) to explore the neurovascular coupling mechanism of working memory. In the data analysis, the convolution matrix of time series of different trials in EEG data and hemodynamic response function (HRF) and the blood oxygen change matrix of fNIRS are extracted as the coupling characteristics. Then, canonical correlation analysis (CCA) is used to calculate the cross correlation between the two modal features. The results show that CCA algorithm can extract the similar change trend of related components between trials, and fNIRS activation of frontal pole region and dorsolateral prefrontal lobe are correlated with the delta, theta, and alpha rhythms of EEG data. This study reveals the mechanism of neurovascular coupling of working memory, and provides a new method for fusion of EEG data and fNIRS data.

Electroencephalography/methods , Memory, Short-Term , Neurovascular Coupling/physiology , Prefrontal Cortex , Spectroscopy, Near-Infrared/methods
J. vasc. bras ; 20: e20200143, 2021. tab, graf
Article in English | LILACS | ID: biblio-1250251


Abstract Background There is a spectrum of possibilities for analyzing muscle O2 resaturation parameters for measurement of reactive hyperemia in microvasculature. However, there is no consensus with respect to the responsiveness of these O2 resaturation parameters for assessing reactive hyperemia. Objectives This study investigates the responsiveness of the most utilized muscle O2 resaturation parameters to assess reactive hyperemia in the microvasculature of a clinical group known to exhibit impairments of tissue O2 saturation (StO2). Methods Twenty-three healthy young adults, twenty-nine healthy older adults, and thirty-five older adults at risk of cardiovascular disease (CVD) were recruited. Near-infrared spectroscopy (NIRS) was used to assess StO2 after a 5-min arterial occlusion challenge and the following parameters were analyzed: StO2slope_10s, StO2slope_30s, and StO2slope_until_baseline (upslope of StO2 over 10s and 30s and until StO2 reaches the baseline value); time to StO2baseline and time to StO2max (time taken for StO2 to reach baseline and peak values, respectively); ∆StO2reperfusion (the difference between minimum and maximum StO2 values); total area under the curve (StO2AUCt); and AUC above the baseline value (StO2AUC_above_base). Results Only StO2slope_10s was significantly slower in older adults at risk for CVD compared to healthy young individuals (p < 0.001) and to healthy older adults (p < 0.001). Conversely, time to StO2max was significantly longer in healthy young individuals than in older adult at CVD risk. Conclusions Our findings suggest that StO2slope_10s may be a measure of reactive hyperemia, which provides clinical insight into microvascular function assessment.

Resumo Contexto Existe um espectro de possibilidades na análise dos parâmetros de ressaturação de O2 muscular como uma medida de hiperemia reativa na microvasculatura. No entanto, não há consenso com relação à responsividade desses parâmetros de ressaturação de O2 para avaliação de hiperemia reativa. Objetivos Este estudo investigou a capacidade de resposta dos parâmetros de ressaturação muscular de O2 mais utilizados para avaliar a hiperemia reativa na microvasculatura de um grupo clínico conhecido por apresentar comprometimento da saturação de O2 (StO2). Métodos Foram recrutados 23 jovens saudáveis, 29 idosos saudáveis e 35 idosos com risco para doença cardiovascular. A espectroscopia no infravermelho próximo foi usada para avaliar a StO2 após um teste de oclusão arterial de 5 minutos, no qual os seguintes parâmetros foram analisados: StO2slope_10s, StO2slope_30s e StO2slope_until_baseline (inclinação da StO2 em 10 s, 30 s e até StO2 atingir valores basais); tempo para StO2baseline e tempo para StO2máx (o tempo necessário para StO2 atingir os valores da linha de base e o máximo, respectivamente); ∆StO2reperfusão (a diferença entre o valor de StO2mínimo e StO2máximo); área total sob a curva (StO2AUCt); e área sob a curva acima do valor da linha de base (StO2AUC_above_base). Resultados Apenas StO2slope_10s foi significativamente mais lento em idosos em risco de doença cardiovascular comparados com indivíduos jovens saudáveis (p < 0,001) e idosos saudáveis (p < 0,001). Por outro lado, o tempo para StO2max foi significativamente maior em indivíduos jovens saudáveis do que em idosos em risco de doença cardiovascular. Conclusões Nossos achados sugerem que StO2slope_10s pode ser uma medida de hiperemia reativa, que fornece informações clínicas sobre a avaliação da função microvascular.

Humans , Male , Female , Adult , Middle Aged , Aged , Young Adult , Oxygen Saturation , Hyperemia/diagnosis , Muscles/blood supply , Reference Values , Aging , Cardiovascular Physiological Phenomena , Oxygen Level , Age Factors , Spectroscopy, Near-Infrared/methods , Microcirculation
J. vasc. bras ; 19: e20190027, 2020. tab, graf
Article in Portuguese | LILACS | ID: biblio-1091015


Resumo Contexto A espectroscopia próxima ao infravermelho (NIRS) é uma técnica não invasiva que detecta as alterações hemodinâmicas teciduais. A NIRS pode monitorar de forma contínua as informações fisiológicas vasculares intracranianas. Por ser portátil, ela pode ser utilizada à beira do leito e no centro cirúrgico. Objetivos Avaliar as possíveis alterações hemodinâmicas cerebrais durante a endarterectomia em pacientes com estenoses maiores que 70% utilizando NIRS. Métodos Foram avaliados 10 voluntários portadores de doença carotídea aterosclerótica com indicação de endarterectomia. Após a seleção dos pacientes, que responderam um questionário com dados epidemiológicos e informações referentes à presença de comorbidades, a doença foi confirmada por métodos diagnósticos. No procedimento cirúrgico, utilizou-se a NIRS para monitorização. Foram avaliadas as variáveis saturação de oxigênio (SatO2), hemoglobina total (HbT), hemoglobina reduzida (HbR) e hemoglobina oxigenada (HbO) nos três tempos cirúrgicos pré-, trans e pós-clampeamento carotídeo. Utilizou-se p < 0,05 como nível de significância. Resultados A avaliação dos resultados obtidos por meio das medidas registradas pela NIRS permite afirmar que HbR e SatO2 variam ao longo das etapas da cirurgia. Durante o clampeamento, a variável HbR mostra valores mais elevados que nas outras duas etapas da cirurgia. Por outro lado, a variável SatO2 mostra redução durante o clampeamento. Conclusões A NIRS é um método viável e aplicável de monitorização intracerebral, não invasivo e em tempo real, durante a endarterectomia carotídea, capaz de medir de forma precisa as mudanças das condições hemodinâmicas capilares intracerebrais.

Abstract Backgrounds Near-infrared spectroscopy (NIRS) is non-invasive technique that detects hemodynamic alterations in tissues. It enables continuous monitoring of intracerebral vascular physiologic information. Due to its portable nature, NIRS may be used bedside or in the operating room. Objectives To evaluate use of NIRS for intraoperative monitoring of the brain hemodynamic response, during carotid endarterectomy. Methods 10 patients with atherosclerotic carotid disease scheduled for endarterectomy were evaluated. After patients had been selected, they answered a questionnaire on epidemiological data and information about comorbidities and then carotid disease was confirmed with diagnostic methods. NRIS monitoring was used during the surgical procedure. The variables analyzed before, during and after carotid clamping were oxygen saturation (SatO2), total hemoglobin (THb), reduced hemoglobin (RHb), and oxyhemoglobin (OHb). A p value of <0.05 was considered statistically significant. Results The results obtained from NIRS show that RHb and SatO2 vary during the different stages of surgery. RHb levels are higher during clamping, when compared with the other two surgical stages. On the other hand, SatO2 is lower during clamping. Conclusions During carotid endarterectomy, NIRS is a feasible, real-time, and non-invasive intracranial monitoring method that accurately and reliably measures the changes in intracerebral capillary hemodynamic conditions.

Humans , Male , Female , Middle Aged , Aged , Monitoring, Intraoperative/instrumentation , Endarterectomy, Carotid/instrumentation , Spectroscopy, Near-Infrared/methods , Carotid Artery Diseases/surgery , Cross-Sectional Studies , Prospective Studies , Cerebrum/blood supply , Hemodynamic Monitoring/instrumentation , Intraoperative Period
An. acad. bras. ciênc ; 90(1): 205-217, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-886921


ABSTRACT Soybeans contain about 30% carbohydrate, mainly consisting of non-starch polysaccharides (NSP) and oligosaccharides. NSP are not hydrolyzed in the gastrointestinal tract of monogastric animals. These NSP negatively affect the development of these animals, especially the soluble fraction. This work aimed to establish a method to quantify NSP in soybeans, using high performance liquid chromatography (HPLC), and to estimate correlations between NSP, oligosaccharides, protein and oil. Sucrose, raffinose + stachyose, soluble and insoluble NSP contents were determined by HPLC. Oil and protein contents were determined by near-infrared spectroscopy (NIRS). The soluble PNAs content showed no significant correlation with protein, oil, sucrose and raffinose + stachyose contents, but oligosaccharides showed a negative correlation with protein content. These findings open up the possibility of developing cultivars with low soluble NSP content, aiming to develop feed for monogastric animals.

Animals , Polysaccharides/analysis , Glycine max/chemistry , Soybean Oil/analysis , Oligosaccharides/analysis , Uronic Acids/analysis , Chromatography, High Pressure Liquid/methods , Spectroscopy, Near-Infrared/methods , Animal Feed/analysis
J. vasc. bras ; 14(4): 311-318, out.-dez. 2015. tab, graf
Article in English | LILACS | ID: lil-767702


O relato de sintoma claudicante em pacientes com doença arterial periférica é utilizado como modulador da intensidade de exercício físico para o tratamento clínico, entretanto os valores de oxigenação tecidual nesse momento são desconhecidos. Objetivo Descrever o suprimento tecidual de oxigênio por meio da espectroscopia de luz próxima ao infravermelho ou Near-Infrared Spectroscopy (NIRS) nos momentos em que o paciente relata sintoma claudicante inicial e máximo em testes de exercício. Métodos Nove pacientes, oito homens com 65,63 ± 6,02 anos de idade, previamente diagnosticados com doença arterial periférica, realizaram teste de exercício de carga constante e de carga incremental com monitorização do nível de oxigenação tecidual através da NIRS. As saturações de oxigênio obtidas no momento em que o paciente relata sintoma claudicante inicial e no momento em que relata sintoma claudicante máximo foram comparadas com os valores de saturação da manobra de oclusão arterial por meio do intervalo de confiança de 95% da diferença. Resultados Verificou-se que os valores de saturação nos momentos de sintoma claudicante inicial e máximo são estatisticamente distintos quando comparados àqueles obtidos na manobra de oclusão arterial, entretanto, através da análise percentual do quão distante esses valores encontram-se é possível observar que, do ponto de vista clínico, eles estão próximos. Conclusões A saturação no momento em que o paciente relata sintomas claudicantes inicial e máximo é bastante próxima do valor de saturação no momento de oclusão e do ponto de vista clínico o relato subjetivo de sintoma do paciente é adequado como parâmetro para a prescrição do exercício físico.

The time at which claudication symptoms are reported is used to modulate exercise intensity in clinical treatment of patients with peripheral arterial disease, but tissue oxygenation values at that point are unknown. Objective To describe tissue oxygen supply measured using Near-Infrared Spectroscopy (NIRS) when patients report initial and maximum claudication symptoms during exercise tests. Methods Nine patients (eight men) aged 65.63 ± 6.02 years and previously diagnosed with peripheral arterial disease performed constant load exercise testing and incremental load exercise testing while tissue oxygenation levels were monitored by NIRS. Oxygen saturation values at the times at which each patient reported initial onset of claudication symptoms and maximum claudication symptoms were compared with values obtained during the arterial occlusion maneuver, using the 95% confidence interval of the difference. Results It was found that saturation values at the time of both initial and maximum claudication symptoms were statistically different from saturation during the arterial occlusion maneuver, but on the basis of percentage analysis they were similar from a clinical point of view. Conclusions Oxygen saturations at the time patients report initial and maximum claudication symptoms are very close to saturations during arterial occlusion. From a clinical perspective, subjective patient report of symptoms is an appropriate parameter on which to base exercise prescription.

Humans , Male , Aged , Peripheral Arterial Disease/diagnosis , Exercise , Intermittent Claudication , Surveys and Questionnaires , Spectroscopy, Near-Infrared/methods , Exercise Test/methods
Rev. bras. anestesiol ; 64(4): 241-246, Jul-Aug/2014. tab
Article in English | LILACS | ID: lil-720477


OBJECTIVE: Central blockage provided by spinal anaesthesia enables realization of many surgical procedures, whereas hemodynamic and respiratory changes influence systemic oxygen delivery leading to the potential development of series of problems such as cerebral ischemia, myocardial infarction and acute renal failure. This study was intended to detect potentially adverse effects of hemodynamic and respiratory changes on systemic oxygen delivery using cerebral oxymetric methods in patients who underwent spinal anaesthesia. METHODS: Twenty-five ASA I-II Group patients aged 65-80 years scheduled for unilateral inguinal hernia repair under spinal anaesthesia were included in the study. Following standard monitorization baseline cerebral oxygen levels were measured using cerebral oximetric methods. Standardized Mini Mental Test (SMMT) was applied before and after the operation so as to determine the level of cognitive functioning of the cases. Using a standard technique and equal amounts of a local anaesthetic drug (15 mg bupivacaine 5%) intratechal blockade was performed. Mean blood pressure (MBP), maximum heart rate (MHR), peripheral oxygen saturation (SpO2) and cerebral oxygen levels (rSO2) were preoperatively monitored for 60 min. Pre- and postoperative haemoglobin levels were measured. The variations in data obtained and their correlations with the cerebral oxygen levels were investigated. RESULTS: Significant changes in pre- and postoperative measurements of haemoglobin levels and SMMT scores and intraoperative SpO2 levels were not observed. However, significant variations were observed in intraoperative MBP, MHR and rSO2 levels. Besides, a correlation between variations in rSO2, MBP and MHR was determined. CONCLUSION: Evaluation of the data obtained in the study demonstrated that post-spinal decline in blood pressure and also heart rate decreases systemic oxygen delivery and adversely effects cerebral oxygen levels. However, ...

JUSTIFICATIVA E OBJETIVO: o bloqueio central proporcionado pela raquianestesia possibilita a realização de muitos procedimentos cirúrgicos, enquanto as alterações hemodinâmicas e respiratórias influenciam a oferta de oxigênio sistêmico, levando ao desenvolvimento em potencial de uma série de problemas, como isquemia cerebral, infarto do miocárdio e insuficiência renal aguda. O objetivo deste estudo foi detectar potenciais efeitos adversos das alterações hemodinâmicas e respiratórias sobre a oferta de oxigênio sistêmico, usando métodos oximétricos cerebrais em pacientes submetidos à raquianestesia. MÉTODOS: vinte e cinco pacientes, 65-80 anos de idade, estado físico ASA I-II, programados para correção de hérnia inguinal unilateral sob raquianestesia foram incluídos no estudo. De acordo com o monitoramento padrão, os níveis de oxigênio cerebral foram medidos no início do estudo usando métodos oximétricos cerebrais. O Mini Teste Padronizado do Estado Mental (Standardized Mini Mental Test - SMMT) foi aplicado antes e depois da operação para determinar o nível de funcionamento cognitivo dos casos. Usando uma técnica padrão e quantidades iguais de um fármaco anestésico local (15 mg de bupivacaína a 5%), o bloqueio intratecal foi realizado. Pressão arterial média (PAM), frequência cardíaca máxima (FCM), saturação periférica de oxigênio (SpO2) e níveis cerebrais de oxigênio (rSO2) foram monitorados no pré-operatório por 60 min. Os níveis pré- e pós-operatórios de hemoglobina foram medidos. As variações nos dados obtidos e suas correlações com os níveis cerebrais de oxigênio foram investigadas. RESULTADOS: não observamos ...

JUSTIFICACIÓN Y OBJETIVO: el bloqueo central proporcionado por la raquianestesia posibilita la realización de muchos procedimientos quirúrgicos, mientras que las alteraciones hemodinámicas y respiratorias influyen en la administración de oxígeno sistémico conllevando el desarrollo potencial de una serie de problemas, como la isquemia cerebral, el infarto de miocardio y la insuficiencia renal aguda. El objetivo de este estudio fue detectar potenciales efectos adversos de las alteraciones hemodinámicas y respiratorias sobre la administración de oxígeno sistémico, usando métodos oximétricos cerebrales en pacientes sometidos a la raquianestesia. MÉTODOS: veinticinco pacientes, entre 65 y 80 años de edad, estado físico ASA I-II, programados para la corrección de hernia inguinal unilateral bajo raquianestesia fueron incluidos en el estudio. De acuerdo con la monitorización estándar, los niveles de oxígeno cerebral fueron medidos al inicio del estudio usando métodos oximétricos cerebrales. El Mini Test Estandarizado del Estado Mental se aplicó antes y después de la operación para determinar el nivel de funcionamiento cognitivo de los casos. Usando una técnica estándar y cantidades iguales de un anestésico local (15 mg de bupivacaína al 5%), se realizó el bloqueo intratecal. La presión arterial media (PAM), frecuencia cardíaca máxima (FCM), saturación periférica de oxígeno (SpO2) y niveles cerebrales de oxígeno (rSO2) fueron monitorizados en el preoperatorio durante 60 min. Se midieron los niveles pre y postoperatorios de hemoglobina. Las variaciones en los datos obtenidos y sus correlaciones con los niveles cerebrales de oxígeno fueron investigadas. RESULTADOS: no observamos alteraciones significativas en las medidas de hemoglobina, puntuaciones ...

Aged , Aged, 80 and over , Female , Humans , Male , Anesthesia, Spinal/methods , Herniorrhaphy/methods , Oxygen/metabolism , Spectroscopy, Near-Infrared/methods , Anesthesia, Spinal/adverse effects , Anesthetics, Local/administration & dosage , Bupivacaine/administration & dosage , Hemoglobins/metabolism , Hernia, Inguinal/surgery , Monitoring, Intraoperative/methods , Oximetry
Rev. cuba. farm ; 48(2)abr.-jun. 2014.
Article in Spanish | LILACS, CUMED | ID: lil-731952


Introducción: el clopidogrel bisulfato existe en numerosas formas cristalinas, que varían en su estabilidad fisicoquímica, por lo que algunas de estas formas, patentadas o no, son útiles en la fabricación de medicamentos. Objetivo: identificar las formas cristalinas existentes en dos muestras de clopidogrel bisulfato materia prima comercializadas para la fabricación de medicamentos y el estado de pureza de ambas muestras. Métodos: las muestras de materia prima se obtuvieron de una industria nacional. Se examinaron mediante técnicas analíticas avanzadas como difracción de rayos X, calorimetría diferencial de barrido, termogravimetría y espectroscopia infrarroja. Se compararon los valores encontrados con los del estado del arte reconocidos en la literatura revisada para el clopidogrel bisulfato materias primas y tomados como referencia. Resultados: se obtuvieron los difractogramas, termogramas y espectros de absorción correspondientes a las muestras analizadas. Se utilizó el software TA Universal Analysis para obtener el porcentaje de descomposición, punto de fusión y picos identificadores en las muestras. Conclusiones: la muestra 1 contiene la forma cristalina I del bisulfato de clopidogrel, que no es pura ya que existe una banda característica de la presencia de contaminación con la forma cristalina II. La muestra 2 corresponde a la forma cristalina II del producto en forma pura(AU)

Introduction: clopidogrel bisulphate exists in many crystalline forms that vary in their physicochemical stability: some of these forms either patented or not are useful in the drug production. Objective: to identify the existing crystalline forms in two samples of Clopidogrel bisufhate raw material for the drug and the purity index of both samples. Methods: the raw material samples were taken from a domestic industry. They were tested through advanced analytical techniques such as differential scanning calorimetry, X-ray scattering pattern, infrared spectroscopy and thermogravimetric analysis. The final values were then compared with the well-established state-of-the-art values found in the reviewed literature for the clopidrogrel bisulfate raw materials and accepted as reference. Results: the physicochemical parameters were obtained from the absorption spectra, thermograms and diffractograms. The TA Universal Analysis software yielded the percentage of decomposition, the melting points and the peak identifiers in the samples. Conclusions: its was concluded that the sample 1 contained the crystal form I of the Clopridogrel bisulfate that is not a pure one since there is a characteristic band indicating contamination with the crystalline form II. The sample 2 had the pure crystalline form II of the product(AU)

Humans , Clopidogrel/therapeutic use , Thermogravimetry/methods , X-Ray Diffraction/methods , Spectroscopy, Near-Infrared/methods , Costa Rica , Crystallization/methods
Yonsei Medical Journal ; : 1066-1069, 2013.
Article in English | WPRIM | ID: wpr-121777


The recent introduction of an intraoperative near infrared fluorescence (INIF) imaging system installed on the da Vinci Si(R) robotic system has enabled surgeons to identify intravascular NIF signals in real time. This technology is useful in identifying hidden vessels and assessing blood supply to bowel segments. In this study, we report 3 cases of patients with rectal cancer who underwent robotic low anterior resection (LAR) with INIF imaging for the first time in Asia. In September 2012, robotic-assisted rectal resection with INIF imaging was performed on three consecutive rectal cancer patients. LAR was performed in 2 cases, and abdominoperineal resection was performed in the third case. INIF imaging was used to identify the left colic branch of the inferior mesenteric artery and to assess blood supply to the distal rectum. We evaluated the utility of INIF imaging in performing robotic-assisted colorectal procedures. Our preliminary results suggest that this technique is safe and effective, and that INIF imaging may be a useful tool to colorectal surgeons.

Aged , Female , Humans , Male , Middle Aged , Digestive System Surgical Procedures/methods , Fluorescence , Image Processing, Computer-Assisted/instrumentation , Intraoperative Care , Rectal Neoplasms/surgery , Rectum/surgery , Robotics/methods , Spectroscopy, Near-Infrared/methods , Treatment Outcome
São Paulo; s.n; 2012. 117 p.
Thesis in Portuguese | LILACS | ID: lil-666633


A avaliação da presença de compostos orgânicos voláteis nos efluentes líquidos é importante para atendimento à legislação vigente e proteção do sistema de esgotamento sanitário e da saúde ocupacional. Objetivos: o uso de técnica rápida de identificação e quantificação de compostos orgânicos voláteis do grupo BTEX presentes em amostras de efluentes líquidos através das emissões gasosas permite verificar quais delas não atendem à legislação vigente, através de faixas de concentração de interesse. A possibilidade de efetuar em campo essa avaliação promove maior agilidade nas ações de controle da qualidade do efluente bem como da exposição ocupacional. Também permite racionalizar os custos de monitoramento através da redução das amostras enviadas aos laboratórios. Materiais e métodos: os compostos avaliados causam agravos à saúde e, por serem altamente voláteis, possuem altos percentuais de distribuição no ar. O benzeno é comprovadamente cancerígeno, não existindo limites seguros para exposição a esse composto. A legislação brasileira fornece os subsídios necessários para o controle da produção, usos e disposição de BTEX. Há ações em andamento para um melhor controle e monitoramento da exposição ocupacional ao benzeno, em especial, e também ações para o monitoramento das populações expostas a ele. Com o objetivo de efetuar leituras no campo que identifiquem e quantifiquem os compostos do grupo BTEX, optou-se pela utilização de espectrofotômetro de infravermelho portátil. Resultados: os resultados das leituras das emissões desses compostos foram comparados com os resultados das análises de BTEX efetuadas nos efluentes líquidos. Para tanto, foram considerados os parâmetros existentes na legislação relativos à exposição ocupacional e à legislação de lançamento de efluentes. Conclusão: a avaliação dos resultados permite dizer que é factível a utilização da leitura das emissões gasosas para identificar a presença de BTEX em amostras de efluentes líquidos e que essas l...

Wastewater/analysis , Data Collection/statistics & numerical data , Organic Chemicals/analysis , Occupational Health , Benzene/chemistry , Data Collection/instrumentation , Spectroscopy, Near-Infrared/methods , Health Law , Statistics, Nonparametric , Toluene/chemistry , Xylenes/chemistry
Braz. j. pharm. sci ; 47(2): 289-297, Apr.-June 2011. ilus, tab
Article in English | LILACS | ID: lil-595817


Determination of moisture content in lyophilized solids is fundamental to predict quality and stability of freeze-dried products, but conventional methods are time-consuming, invasive and destructive. The aim of this study was to develop and optimize a fast, inexpensive, noninvasive and nondestructive method for determination of moisture content in lyophilized mannitol, based on an NIR micro-spectrometer instead of a conventional NIR spectrometer. Measurements of lyophilized mannitol were performed through the bottom of rotating glass vials by means of a reflectance probe. The root mean standard error of prediction (RMSEP) and the correlation coefficient (R²pred), yielded by the pre-treatments and calibration method proposed, was 0.233 percent (w/w) and 0.994, respectively.

A determinação do conteúdo de umidade em sólidos liofilizados é fundamental para se prever a qualidade e a estabilidade de produtos liofilizados, mas os métodos convencionais consomem muito tempo, são invasivos e destrutivos. O objetivo desse estudo foi desenvolver e otimizar um método rápido, econômico, não invasivo e não destrutivo para a determinação do conteúdo de umidade em manitol liofilizado, com base em microespectrômetro de infravermelho próximo ao invés de um espectrômetro de infravermelho próximo convencional. As medidas de manitol liofilizado foram realizadas através do fundo de recipiente de vidro em rotação por meio de sonda de reflectância. A raíz do erro médio padrão de predição (RMSEP) e o coeficiente de correlação (R²pred) obtidos pelo prétratamento e pelo método de calibração proposto foram, respectivamente, 0,233 por cento (p/p) e 0,994.

Diagnosis/analysis , Diagnosis/methods , Spectroscopy, Near-Infrared/methods , Freeze Drying , Humidity , Mannitol/chemistry , Multivariate Analysis , /methods , Sampling Studies , Water , Water Quantity
Bulletin of Pharmaceutical Sciences-Assiut University. 2010; 33 (2): 217-224
in English | IMEMR | ID: emr-110803


The aim of the present study was to develop ibuprofen [IBU]-loaded pellets by melt solidification technique using Gelucire 50/13 [GL] as a lipid carrier in different concentrations. This system was intended to prolong the drug release in order to minimize the drug related adverse effects and improve bioavailability in different gastrointestinal tract conditions. The prepared pellets were evaluated using scanning electron microscopy [SEM], Infrared spectroscopy [IR], and Differential scanning calorimetry [DSC] studies. Process yield, drug loading, encapsulation efficiency, and particle size distribution were also investigated. The effect of agitation speed and amount of GL on pellets properties was evaluated. In-vitro drug release of ibuprofen from prepared pellets was studied in HCl buffer [pH1.2] for 2 hrs, and in phosphate buffer [pH 7.4] for up to 8 hrs. The obtained pellets were spherical in shape with smooth surfaces; and GL showed no interaction with the drug. The release of drug from the pellets showed low percentage of drug release in pH 1.2. However, at pH 7.4 the obtained results showed that optimum levels of drug were released in a sustained manner

Fats , Drug Carriers , Delayed-Action Preparations , Microscopy, Electron/methods , Spectroscopy, Near-Infrared/methods , Colorimetry/methods
São Paulo; s.n; 2010. 82 p. (BR).
Thesis in Portuguese | LILACS, BBO | ID: lil-563672


Objetivo: avaliar a relação de dependência da tensão de polimerização (TP), grau de conversão (GC), taxa máxima de reação de polimerização (Rpmax), contração volumétrica (CV), módulo de elasticidade (E) e tangente de delta (tanδ) com o conteúdo inorgânico e proporção de BisGMA:TEGDMA e verificar as possíveis relações de dependência entre a TP e as demais variáveis-resposta. Material e métodos: Foram preparadas vinte formulações, com concentrações de carga de 40, 50, 60 ou 70 % em peso de vidro de bário e proporções molares de BisGMA:TEGDMA de 3:7, 4:6, 5:5, 6:4 ou 7:3. TP (n=7) foi determinada pela inserção do compósito entre bastões de acrílico fixados às garras de uma máquina universal de ensaios e dividindo-se a máxima força de contração registrada pela secção transversal dos bastões. GC e Rpmax foram determinados por espectroscopiano infra-vermelho próximo (n=5). CV foi mensurada em dilatômetro de mercúrio (n=3). E foi obtido através do teste de flexão em três pontos (n=10). Tanδ foi determinada por nanoidentação dinâmica (n=3). Foram realizadas análises de regressão para avaliar a influência da fração inorgânica e da proporção monoméricanas variáveis estudadas e para avaliar o efeito das variáveis-resposta na determinação da TP. Resultados: Todas as variáveis se mostraram dependentes da concentração inorgânica e conteúdo monomérico. TP, GC e Rpmax foram mais influenciados pela matriz, enquanto que CV, E e tanδ apresentaram maior efeito da concentração de carga. TP mostrou-se dependente dos fatores CV e GC. Conclusões: a formulação de compósitos com baixa TP deve observar criteriosamente a fração inorgânica e o conteúdo monomérico, sendo o principal desafio encontrar formulações com baixa CV, uma vez que os demais fatores demonstraram não ter influência significativa e o GC do material não deve ser sacrificado com o propósito de reduzir a TP.

Objective: To evaluate the dependence relationship of polymerization stress (PS), degree of conversion (DC), maximum polymerization rate (Rpmax), volumetric shrinkage (VS), elastic modulus (E) and loss tangent (tanδ) with the inorganic content and BisGMA:TEGDMA ratio and verify possible relationship among PS and the others variables. Materials and Methods: twenty resin composites were studied, having barium glass concentration of 40, 50, 60 or 70 wt% and BisGMA:TEGDMA molar ratio of 3:7, 4:6, 5:5, 6:4 or 7:3. PS (n=7) was determined inserting the composite between acrylic rods fixed to clamps of an universal test machine and dividing the maximum load recorded by the rods cross-sectional area. DC and Rpmax were determined by near infrared spectroscopy in real time (n=5). VS was measured by mercury dilatometer (n=3). E was obtained by three-point bending test (n=10). Tanδ was determined by dynamic nanoindentation (n=3). Regression analyses were performed to evaluate the relationship of inorganic content and monomeric ratio on studied variables and to evaluate the effect of the variables on the polymerization stress development. Results: All variables showed dependence on inorganic concentration and monomeric content. PS, DC and Rpmax were more affected by resin matrix whereas VS, E and Tanδ were more strongly influenced by filler fraction. PS was dependent on both volumetric shrinkage and degree of conversion. Conclusions: in order to obtain composites formulations which provide low polymerization, the inorganic concentration and monomeric contend have to be carefully observed. The main challenge is to design formulations with low VS since the others factors apparently do not have significance and PS should not come at the expense of DC.

Composite Resins , Spectroscopy, Near-Infrared/methods
São Paulo; s.n; 2009. 183 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-561799


Os relaxantes neuromusculares não despolarizantes são fármacos indispensáveis nos procedimentos cirúrgicos que requerem entubação endotraqueal, visto que diminuem o tônus muscular. Quimicamente são divididos em derivados isoquinolinicos e derivados de esteróides, esses últimos com maior aplicação clinica e comercialização no Brasil. Assim sendo, é importante a validação de métodos analíticos para o controle de qualidade com alternativas confiáveis que garantam sua eficácia e segurança. Os brometos de vecurônio, de pancurônio e de rocurônio são fármacos relaxantes neuromusculares não despolarizantes derivados de esteróides. As propriedades farmacológicas destes fármacos são significativamente diferentes entre si, porém, as propriedades químicas são bastante similares. Na presente pesquisa foram desenvolvidos e validados métodos analíticos de separação (cromatografia líquida de alta eficiência e eletroforese capilar) para cada fármaco. Estes métodos foram aplicados a medicamentos comercializados no Brasil. Para todos os métodos cromatográficos foi utilizada uma coluna amino devido a seu caráter polar. Em função da baixa absorção dos três fármacos na região ultravioleta, os métodos eletroforéticos foram aplicados com detecções indiretas utilizando substâncias cromóforas. Comparando-se as técnicas utilizadas para determinação dos fármacos nos medicamentos isoladamente, não houve diferença significativa com nível de confiança de 95,0%. Nos testes de hipótese aplicados (F-Snedecor e t-Student), não foram observadas diferenças na precisão (variâncias) e no valor encontrado dos fármacos contidos nas amostras estudadas (comparação de duas médias).

The non-depolarizing neuromuscular relaxant drugs are essential in surgical procedures requiring endotracheal intubation, as they decrease muscle tonics. These drugs are chemically divided in isoquinolines derivatives and steroid derivatives, this latter group, with greater clinical application and commercialization in Brazil. Therefore, the study and validation of analytical methods are important for quality control with reliable alternatives to ensure their effectiveness and safety. The vecuronium, pancuronium and rocuronium bromides are steroid derivatives presenting non-depolarizing neuromuscular relaxant action. Pharmacological properties of these drugs differ significantly, however, its chemical properties are quite similar. In this research, analytical separation methods (high performance liquid chromatography and capillary electrophoresis), for each drug, were developed and fully validated. The methods were applied to pharmaceutical formulations commercialized in Brazil. For all chromatographic methods, an amino column was used, due to its polar characteristics. Due to the low absorption of the three drugs in the ultraviolet region, electrophoretic methods has been applied with indirect detection using chromophoric substances. When comparing both techniques used for quantitative determination of these drugs in pharmaceutical products, no significant difference was observed using a confidence level of 95.0%. By applying hypothesis tests (F-Snedecor and t-Student), it was not observed difference in precision (variance) and in the found amount of drugs contained in the selected samples (comparison of two means).

Vecuronium Bromide/analysis , Technological Development/analysis , Technological Development/methods , Preparation Scales , Analytic Sample Preparation Methods , Chromatography, Liquid/methods , Drug Evaluation, Preclinical , Spectroscopy, Near-Infrared/methods
Journal of Korean Medical Science ; : 674-677, 2008.
Article in English | WPRIM | ID: wpr-9469


The estimation of plasma hemoglobin concentration (Hb) is among one of the daily activities in the practice of clinical anesthesiology. The near-infrared spectroscopy of the brain (rSO2) represents a balance between cerebral oxygen delivery and consumption. This study was designed to assess the value of rSO2 in the prediction of the Hb level while other variables were mathematically controlled. Thirty healthy adult patients undergoing spine surgery, expected to have a moderate degree of intraoperative bleeding, were enrolled in this study. General anesthesia was given and ventilation was mechanically controlled. Measurement of Hb and PaCO2 were performed at random periods of time. We obtained a total of 97 data combinations for the 30 study patients. The Hb was regressed by independent variables including rSO2 and PaCO2. A multilinear regression analysis was performed and the final regression equation was expressed only with statistically significant variables. The measured Hb was tightly regressed with three variables. The final regression equation was Hb=+8.580+0.238.rSO2-0.338.PaCO2-0.004.anesthetic exposure duration (Tmin) (p=0.000, r(2)=0.809). Near-infrared spectroscopy was shown to be a valuable predictor of plasma Hb in the clinical anesthesiology setting.

Adult , Aged , Female , Humans , Male , Middle Aged , Brain/metabolism , Cerebrovascular Circulation , Hemoglobins/analysis , Oximetry , Oxygen/metabolism , Spectroscopy, Near-Infrared/methods
DARU-Journal of Faculty of Pharmacy Tehran University of Medical Sciences. 2005; 13 (2): 52-55
in English | IMEMR | ID: emr-70324


The urea breath test [UBT] which is carried out with [13]C or [14]C labeled urea is one of the most important non invasive methods for detection of Helicobacter pylori infection. Application of [13]C-UBT is becoming increasingly popular because of its non radioactive nature which makes it suitable for diagnostic purposes in children and women of child bearing ages. While isotope ratio mass spectrometer [IRMS] is generally used to detect [13]C in expired breath, this instrument is expensive and recently non dispersive isotope selective infrared [NDIR] spectroscopy which is a lower cost technique has been employed as a reliable counterpart for IRMS in small clinics. The aim of this study was to assess the validity of NDIR spectroscopy technique in Iranian population in comparison with histological examination, rapid urease test and [14]C-urea breath test as gold standard. Seventy six patients with dyspepsia were underwent [13]CUBT for diagnosis of Helicobacter pylori infection. Good agreements were found between the [13]C-UBT and gold standard methods. The [13]C-UBT showed 100% sensitivity, 97.3% specificity, 97.56% positive predictive value, 100% negative predictive value and 98.65% accuracy. On the basis of these results it could be concluded that [13]C-UBT performed with NDIR spectroscopy is a reliable, accurate and non invasive diagnostic tool for detection of Helicobacter pylori infection in the Iranian population

Humans , Male , Female , Breath Tests/methods , Urea , Spectroscopy, Near-Infrared/methods , Spectroscopy, Near-Infrared/statistics & numerical data , Health Surveys
Rev. Asoc. Odontol. Argent ; 92(4): 361-366, ago.-sept. 2004. ilus, tab, graf
Article in Spanish | LILACS | ID: lil-390918


Se modificó la matriz orgánica de composites dentales a partir de la síntesis de nuevos monómeros. Estos fueron caracterizados por espectroscopía infrarroja y resonancia magnética nuclear y se determinó su densidad y viscosidad. Además, se evaluó la contracción de polimerización total alcanzada por dichos monómeros puros y por mezclas de éstos con cantidades crecientes de Bis-GMA. La caracterización espectroscópica de los monómeros sintetizados corroboró la introducción de las modificaciones propuestas. La viscosidad de estos compuestos fue significativamente menor que la del Bis-GMA. Matrices orgánicas con los monómeros derivados presentaron menor contracción que la de las mismas proporciones de Bis-GMA y TEGDMA. De lo anterior se concluye que: a) la acilación del Bis-GMA permite obtener nuevos monómeros de menor viscosidad, ya que se elimina la posibilidad de formar uniones hidrógeno intermoleculares. b) las matrices orgánicas donde se reemplaza el TEGDMA por los monómeros sintetizados, Ac-Bis-GMA y Bz-Bis-GMA, generan menor contracción de polimerización que las originales. Realizado dentro del proyecto O022 de la Universidad de Buenos Aires, Argentina

Composite Resins , Light , Bisphenol A-Glycidyl Methacrylate , Schools, Dental , Spectroscopy, Near-Infrared/methods , Magnetic Resonance Imaging , Methylmethacrylate , Research Design , Data Interpretation, Statistical , Surface Properties , Viscosity