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1.
Pesqui. vet. bras ; Pesqui. vet. bras;38(4): 586-594, abr. 2018. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-955368

ABSTRACT

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been shown to be an alternative method for identification of bacteria via their protein profile spectra, being able to identify bacteria at the genus, species and even at subspecies level. With the aim of large-scale identification of pathogens causing mastitis by this platform, a total of 305 isolates of bacteria identified from cows with subclinical mastitis were analyzed by conventional microbiological culture (MC) as well as by MALDI-TOF MS coupled with Biotyper data processing. Approximately 89% of the identifications performed by MALDI-TOF MS were consistent with results obtained by MC. From the remaining isolates (11%), 6.3% of isolates were classified as misidentified (discordance for both genus and species level), and 4.7% showed identification agreement at the genus level but not at the species level, being classified as unidentified at species level. The disagreement results were mostly associated with identification of Streptococcus and Enterococcus species probably due to the narrow phenotypic similarity between these two genera. These disagreement results suggest that biochemical assays might be prone to identification errors and, MALDI-TOF MS therefore may be an alternative to overcome incorrect species-specific identification. Standard microbiological methods for bovine mastitis diagnosis are time consuming, laborious and prone to errors for some bacteria genera. In our study, we showed that MALDI-TOF MS coupled with Biotyper may be an alternative method for large-scale identification of bacteria isolated from milk samples compared to classical microbiological routine protocols.(AU)


A espectrometria de massas (MALDI-TOF MS) tem mostrado ser um método alternativo para a identificação de bactérias, sendo capaz de identificar as bactérias causadoras de mastite em gênero, espécie ou até mesmo subespécie. Com o objetivo de identificar os patógenos causadores de mastite em grande-escala por esta plataforma, um total de 305 isolados bacterianos oriundos de vacas com mastite subclínica foram analisados pela cultura microbiológica convencional (CM) e pela MALDI-TOF MS acoplada ao software Biotyper. Aproximadamente 89% das identificações realizadas pela MALDI-TOF MS foram consistentes com os resultados obtidos pela CM. Do restante de isolados bacterianos (11%), 6,3% foram classificados como identificação errônea (discordância de gênero e espécie), e 4,7% apresentaram concordância de gênero, mas discordância da espécie. Os resultados que apresentaram divergência estavam mais associados com a identificação das espécies de Streptococcus spp. e Enterococcus spp. devido à similaridade fenotípica entre os dois gêneros. Estes resultados divergentes sugerem que os ensaios bioquímicos podem ser propensos a erros de identificação, por isso a MALDI-TOF MS pode ser considerada um método alternativo para superar os erros de identificação da CM. A cultura microbiológica padrão e os ensaios bioquímicos utilizados na identificação de agentes causadores de mastite são demorados, trabalhosos e propensos a erros quando utilizados na identificação em nível de espécie. No presente estudo, demonstramos que a MALDI-TOF MS acoplada ao software Biotyper pode ser considerada um método alternativo de identificação de bactérias causadoras de mastite em grande-escala quando comparado com a cultura microbiológica convencional.(AU)


Subject(s)
Animals , Cattle , Spectrum Analysis/statistics & numerical data , Mastitis/diagnosis , Mastitis/veterinary
2.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 946-956, maio-jun. 2018. graf, tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-911943

ABSTRACT

O presente trabalho foi realizado com o objetivo de desenvolver um método para a determinação de CMP em leite UAT por meio da aplicação da espectroscopia de infravermelho próximo. Leites UAT de oito marcas diferentes foram utilizados para a construção dos modelos de calibração. Os resultados demonstram que, para o desenvolvimento de um modelo de calibração adequado para a determinação de CMP em leite UAT, deve-se utilizar, juntamente com o método de regressão PLS, o método de seleção de espectros máxima distância e os pré-tratamentos 2ª derivada e variável normal padronizada. Além disso, pôde-se determinar que as regiões do infravermelho próximo mais correlacionadas com os movimentos vibracionais dos aminoácidos presentes no CMP foram: 1100-1310; 1400-1430; 1490-1550; 1640-1680; 1780-1970; 2020-2100 e 2310-2350nm. Conclui-se que a espectroscopia de infravermelho próximo pode ser uma alternativa para a determinação de CMP em leite UAT, desde que haja um conjunto de calibração com amostras representativas da população a ser predita no futuro.(AU)


his work´s objective was to develop an UHT milk caseinomacropeptide determination method trough NIR spectroscopy application. Eight UHT milk trademarks are used to produce a mathematical calibration model. The results of NIR analysis suggested that to produce a suitable calibration model, partial least-square regression (PLSR) must be used, with maximum distance in wavelenght space to select spectra, pre - treatment with 2nd derivative and standard normal variant (SNV). Also, suitable near-infrared regions more correlated with CPM aminoacids vibrational movements: 1100-1310; 1400-1430; 1490-1550; 1640-1680; 1780-1970; 2020-2100; and 2310-2350nm. Therefore, NIR spectroscopy can be an alternative to caseinomacropeptide determination of UHT milk, since there was a representative calibration set with a large enough and representative sample of entire population to be predicted in the future.(AU)


Subject(s)
Cytidine Monophosphate , Milk , Spectrum Analysis/statistics & numerical data
3.
Braz. J. Pharm. Sci. (Online) ; 53(1): e16050, 2017. tab, graf
Article in English | LILACS | ID: biblio-839441

ABSTRACT

ABSTRACT Continuous wavelet transform (CWT) was proposed for the simultaneous determination and dissolution profiles of valsartan (VAL) and hydrochlorothiazide (HCT) in tablets, without the use of a chemical separation procedure. The CWT approach was applied to the original UV spectra and their ratio spectra in the optimal wavelength ranges. After testing several wavelet families, Mexican hat function-CWT and Daubechies7-CWT (mexh-CWT and db7-CWT, respectively) were found to be suitable for the transformation of the original UV spectra. In the following procedure, mexh-CWT and Coiflets3-CWT (coif3-CWT) were found to be appropriate for the signal analysis of ratio spectra (RS) of VAL/HCT and HCT/VAL. Calibration graphs for VAL and HCT were obtained by measuring db7-CWT and mexh-CWT amplitudes in the transformation of the original absorption spectra and RS-coif-CWT and RS-mexh-CWT amplitudes in the transformation of the ratio spectra. The validity and applicability of the proposed CWT methods were evaluated through the analysis of an independent set of synthetic binary mixtures consisting of VAL and HCT. The proposed signal processing methods were then successfully applied to the simultaneous quantitative evaluation and simultaneous dissolution profiles of the related drugs in commercial tablets, with good agreement reported for the experimental results.


Subject(s)
Tablets/pharmacokinetics , Dissolution/classification , Wavelet Analysis , Valsartan/administration & dosage , Hydrochlorothiazide/administration & dosage , Spectrum Analysis/statistics & numerical data
4.
Belo Horizonte; s.n; 2016. 82 p. ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-916177

ABSTRACT

Os enxertos de origem autógena são osteogênicos e possuem como vantagens a produção de tecido ósseo originário do próprio organismo. A sua limitação é a grande morbidade cirúrgica. O biovidro é uma cerâmica bioativa com disponibilidade ilimitada que leva a uma cirurgia com menor morbidade. O presente estudo teve como objetivo avaliar o biovidro teste durante o reparo ósseo e compará-lo com outros substitutos ósseos, em defeitos cirúrgicos experimentais em tíbia de ratos. O biovidro teste (CEELBIO, Belo Horizonte, Brasil), previamente caracterizado foi comparado com o Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA), através de espectroscopia na região do infravermelho, microscopia eletrônica de varredura (MEV), espectroscopia de dispersão em energia (EDS) e fluorescência de Rx. Após as análises estruturais, deu-se início ao estudo in vivo. Foram utilizados 120 ratos (rattus norvegicus albinus, Wistar) machos, com aproximadamente 7 a 8 semanas. Os defeitos ósseos foram realizados na tíbia direita dos animais e preenchidos de acordo com a seguinte divisão: Grupo I- controle negativo, sem preenchimento; Grupo II- foi preenchido por Biogran®; Grupo III- preenchido por biovidro teste; Grupo IVcontrole positivo, com preenchimento com osso autógeno. Nos períodos de 7, 14, 21, 28, 49 e 70 dias pós-operatório, os animais foram eutanasiados e os processos de mineralização óssea e reparo foram analisados através de histomorfometria (% de osso neoformado no sítio do defeito). Níveis de BMP-2 foram mensurados através de ensaio de ELISA. Análise estatística foi realizada utilizando programa SPSS (versão 20.0, SPSS Inc., Chicago, USA). Os resultados da análise histológica demonstraram que, no controle negativo, houve neoformação óssea até os 14 dias (20,40%, p<0,001) e depois houve reabsorção em até 21 dias (6,60%, p<0,001). No grupo de Biogran®, houve uma neoformação óssea junto aos grãos em 7 dias (34,20%, p= 0,019) e que se manteve enquanto o material estava presente nos defeitos em 70 dias (15,67%, p= 0,048). O biovidro teste foi reabsorvido totalmente até 21 dias e os picos de osso neoformado foram observados em 7 (21,00%, p= 0,019) e 49 dias (15,60%, p= 0,036). Nesse grupo, células semelhantes a macrófagos, dispostas em lençol, foram visualizadas junto a tecido ósseo neoformado. Quanto ao controle positivo, o osso autógeno foi totalmente reabsorvido em até 14 dias e o pico de formação óssea se deu nesse 9 mesmo momento, em 14 dias, (40,80%, p<0,001), mostrando-se, nos tempos subsequentes, similar ao controle negativo. Células gigantes multinucleadas foram encontradas em áreas de remodelação óssea, junto ao Biogran® e ao biovidro teste. Os níveis de BMP-2 no grupo controle negativo se mostraram maiores nos tempos de 7 (418,80pg/mL, p= 0,871) e 28 dias (346,36 pg/mL, p= 0,035). No grupo Biogran® o pico de BMP-2 se deu em 7 dias (471,95 pg/mL, p= 0,871). O biovidro teste teve seu pico de liberação de BMP-2 em 7 dias também (471,39 pg/mL, p= 0,871). Já o controle positivo apresentou nível de BMP-2 em maior quantidade nos tempos de 7 (346,55 pg/mL, p= 0,871) e 21 dias (407,57 pg/mL, p= 0,300). O biovidro é um material degradável, e com características biológicas de osteoindução e osteocondução


The autogenous origin grafts are osteogenic and have the advantage of producing bone tissue originated from the body itself. Its limitation is the great surgical morbidity. The bioglass is a bioactive ceramic with unlimited availability that leads to a surgery with less morbidity. This study aimed to evaluate the bioglass test during bone repair and to compare it with other bone substitutes in experimental surgical defects in the tibia of rats. The bioglass test (CEELBIO, Belo Horizonte, Brazil), has been characterized and compared to the Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA) by spectroscopy in the infrared, scanning electron microscopy (SEM), EDS spectroscopy and Rx fluorescence. The study in vivo has been started after the structural analysis. 120 rats (Rattus norvegicus albinus, Wistar rats), with approximately 7 to 8 weeks, were used. The bone defects were performed in the right tibia of animals and filled according to the following breakdown: Group I- negative control without filling; Group II- filled by Biogran®; Group III- filled with bioglass test; IV- positive control group, with filling of autogenous bone. At 7, 14, 21, 28, 49 and 70 postoperative days, the animals were euthanized and bone mineralization processes and repair were analyzed by histomorphometry (% of newly formed bone in the defect site). BMP-2 levels were measured by ELISA assay. Statistical analysis was performed using SPSS (version 20.0, SPSS Inc., Chicago, USA). The results of the histological analysis showed that in the negative control there was no bone growth up to 14 days (20.40%, p <0.001) and after reabsorption, within 21 days (6.60%, p <0.001). In Biogran® group, there was new bone formation along the grain in 7 days (34.20%, p = 0.019) and that was maintained as the material was present in shortcomings in 70 days (15.67%, p = 0.048) . The test bioglass was completely reabsorbed within 21 days; new bone formation and peaks were observed in 7 (21.00%, p = 0.019) and 49 days (15.60%, p = 0.036). In this group, macrophage-like cells arranged in sheets, were viewed with the newly formed bone. On the positive control, autologous bone was completely reabsorbed within 14 days, and the peak bone formation occurred at the same moment, within 14 days (40.80%, p <0.001), showing, in subsequent occasions, similar to control negative. Multinucleated giant cells were found in areas of bone remodeling, with the Biogran® and test bioglass. BMP-2 levels in the negative control group were higher in 7 (418,80pg / ml, p = 11 0.871) and 28 days (346.36 pg / ml, p = 0.035). In Biogran® group peak BMP-2 occurred within 7 days (471.95 pg / ml, p = 0.871). The test bioglass had its peak BMP-2 release in 7 days as well (471.39 pg / ml, p = 0.871). The positive control showed BMP-2 level in greater quantities in 7 (346.55 pg / ml, p = 0.871) and 21 days (407.57 pg / ml, p = 0.300). The test bioglass is a biodegradable material, with biological characteristics of osteoinduction and osteoconduction


Subject(s)
Animals , Rats , Bone Regeneration , Ceramics/analysis , Glass/analysis , Osteogenesis/genetics , Fluorescence , Microscopy, Electrochemical, Scanning/statistics & numerical data , Spectrum Analysis/statistics & numerical data
5.
Journal of Advanced Research. 2013; 4 (2): 155-161
in English | IMEMR | ID: emr-168517

ABSTRACT

A solid acid membranes based on poly [vinyl alcohol] [PVA], sodium bromide [NaBr] and phosphoric acid [H[3]PO[4]] were prepared by a solution casting method. The morphological, IR, electrical and optical properties of the [PVA][0.7][NaBr][0.3][H[3]PO[4]][xM] solid acid membranes where x =0.00, 0.85, 1.7, 3.4, 5.1 M were investigated. The variation of film morphology was examined by scanning electron microscopy [SEM] studies. FTIR spectroscopy has been used to characterize the structure of polymer and confirms the complexation of phosphoric acid with host polymeric matrix. The temperature dependent nature of ionic conductivity and the impedance of the polymer electrolytes were determined along with the associated activation energy. The ionic conductivity at room temperature was found to be strongly depends on the H[3]PO[4] concentration which it has been achieved to be of the order 4.3 x 10[-3] S/cm at ambient temperature. Optical measurements showed a decrease in optical band gap and an increase in band tail width with the increase of phosphoric acid. The data shows that the [PVA][0.7][NaBr][0.3][H[3]PO[4]][xM] solid acid membrane is promising for intermediate temperature phosphoric acid fuel cell applications


Subject(s)
Phosphoric Acids/chemistry , Bioelectric Energy Sources/statistics & numerical data , Bromides/chemistry , Microscopy, Electron/statistics & numerical data , Spectrum Analysis/statistics & numerical data
6.
Rev. ing. bioméd ; 4(8): 34-40, jul.-dic. 2010. graf, ilus
Article in Spanish | LILACS | ID: lil-590328

ABSTRACT

Con el objetivo de discriminar lesiones benignas y malignas en la piel humana a partir de espectros de reflexión difusa, se han analizado diferentes algoritmos de clasificación usando el software de aprendizaje automático y reconocimiento de patrones WEKA. Además, dada la alta dimensionalidad de la señal espectral, fue empleada una técnica selección de atributos para determinar las variables que aporten la mayor cantidad de información. Se probó la clasificación de la señal usando los algoritmos de máquinas de vectores de soporte, redes neuronales y bosques aleatorios, el desempeño fue evaluado usando el promedio de la k-fold cross-validation tomando en cuenta los porcentajes de instancias clasificadas correctamente, el índice kappa, el área bajo la curva ROC, la sensibilidad, y la especifidad. Finalmente se demuestra que el algoritmo de redes neuronales con los parámetros momentum y learning rate en 0,6 y 0,3 respectivamente, es el que mejor se adapta al problema de reconocimiento de patrones ya que clasifica correctamente al 89,89% de los casos.


In order to differentiate between benign and malignant lesions in the human skin using diffuse reflection spectra, different classification algorithms were tested using the WEKA data mining software. In addition, due to the high dimensionality of the spectral signal, an attribute selection technique was applied to determine the variables that contribute with more information. The spectral signal classification was tested using support vector machines, neural networks and random forests, their performance was measured using the k-fold cross-validation percentages of the Kappa statistic, area under the ROC curve, specificity and sensitivity. Finally it is shown that the one layer neural network with 6 neurons and the parameters momentum and learning rate in 0.6 and 0.3 respectively, is best suited to the problem of pattern recognition, achieving correctly classify 89.89% of the cases.


Subject(s)
Spectrum Analysis/statistics & numerical data , Spectrum Analysis/instrumentation , Spectrum Analysis/methods , Skin Neoplasms/diagnosis , Skin Neoplasms/prevention & control , Pattern Recognition, Automated , Neural Networks, Computer
7.
Egyptian Journal of Pharmaceutical Sciences. 2006; 47: 73-87
in English | IMEMR | ID: emr-182234

ABSTRACT

Two simple, rapid and accurate techniques have been developed for the determination of lorazepam, delorazepam and tetrazepam in the presence of their degradation products. The first one depends on the derivative ratio spectrophotometry while the second depends on spectrodensitometry. The validity of the proposed procedures was proved using standard addition technique and laboratory-prepared mixtures of the drugs and their degradation products. The proposed procedures were successfully applied for the drugs analysis in their tablet dosage form


Subject(s)
Lorazepam , Tranquilizing Agents , Spectrum Analysis/statistics & numerical data , Spectrophotometry/statistics & numerical data , Drug Stability , Densitometry/statistics & numerical data , Chromatography, Thin Layer
8.
REBLAMPA Rev. bras. latinoam. marcapasso arritmia ; 13(3): 139-142, jul.-set. 2000. tab
Article in Portuguese | LILACS | ID: lil-315274

ABSTRACT

A Doença de Chagas (DC) é uma infecção sistêmica generalizada, normalmente crônica, cujo agente etiológico é o Tripanossoma cruzi, que parasita as células miocárdicas, lesa o sistema de condução e perturba o controle autonômico, levando a uma cardiomiopatia dilatada e arritmias cardíacas. A análise da variabilidade da frequência cardíaca com o domínio de tempo e de freqüência é uma forma simples e prática de avaliar a função autonômica. O objetivo do estudo foi a avaliação de pacientes com DC usando as variáveis de domínio de tempo e de frequência. Foram comparados um grupo de 81 pacientes com DC (47 na fase indeterminada, 8 do sexo masculino, idade média de 55,07 Ý 10,75 anos, e 34 na crônica, 8 do sexo masculino, idade média de 57,46 Ý 11,59 anos) e um grupo controle de 24 pacientes (7 do sexo masculino, idade média de 48,50 Ý 13,93 anos). Obtidas as variáveis de todos os indivíduos através do Holter 24 horas (SDNN, índice de SDNN e de SDANN, rMSSD, pNN50, LF e HF), utilizou-se a análise de variância (a=5por cento) como teste estatístico. Para o SDNN, o índice de SDANN e o HF não houve diferença estatística entre os grupos (p=0,01). Uma diferença estatística foi encontrada entre o grupo controle e os grupo de pacientes chagásicos (indeterminado e crônico) com relação ao SDANN e o LF (p=0,01). Em relação ao grupo controle, os chagásicos apresentaram as variáveis rMSSD e pNN50 com valores estatisticamente maiores. Usando a análise espectral, foi observada uma redução na capacidade da resposta simpática, bem como uma diminuição global da função autonômica observada pela redução do SDANN em ambos os grupos de pacientes chagásicos


Subject(s)
Humans , Male , Adult , Middle Aged , Chagas Disease/physiopathology , Heart Rate/physiology , Spectrum Analysis/statistics & numerical data , Data Interpretation, Statistical
9.
Egyptian Journal of Occupational Medicine. 1990; 14 (1): 160-170
in English | IMEMR | ID: emr-145562

ABSTRACT

The effects of chronic lead exposure on the cardiovascular system were investigated in the workers in the battery industry at Chloride Company. One hundred and ten workers exposed to lead were selected randomly, also 45 workers who have never been exposed to lead before, of comparable age group and socioeconomic standard were selected randomly to be the control group. General clinical examination, cardiovascular manifestations [by an observation sheet], blood pressure determination were carried out and blood lead, urinary delta amino levulenic acid and lipogram pattern [total lipids, cholesterol and its fractions, triglycerides and B/A lipoproteins] were determined. Also lactic acid dehydrogenase and lactic acid isoenzymes estimation were performed. The atmospheric lead concentration was found to be 0.039 - 0.28 ug/m3. The present study showed high prevalence of cardiovascular manifestations [27.3%] and hypertension [35.5%] among exposed workers with significant correlation between systolic and diastolic blood pressure and some parameters of lipogram pattern on one hand with blood lead and urinary delta amino levulenic acid


Subject(s)
Humans , Male , Cardiovascular Diseases , Workplace , Air/analysis , Lipids , Triglycerides/blood , Surveys and Questionnaires , Spectrophotometry, Atomic , Spectrum Analysis/statistics & numerical data , Biomarkers
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