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1.
J Chem Inf Model ; 63(17): 5446-5456, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625081

RESUMEN

A key aspect of producing accurate and reliable machine learning models for the prediction of properties of quantum chemistry (QC) data is identifying possible data characteristics that may negatively influence model training. In previous work, we identified that molecules and materials with a low volume of the convex hull (VCH) of atomic positions may be harmful in model training and a source of prediction outliers. In this paper, we extend this analysis further and develop a biased sampling study to evaluate the influence of VCH on the training data of a model using different structures of molecules and materials. Our study confirms that VCH influences model training and shows the importance of using homogeneous geometric characteristics of structures when building new data sets or selecting training sets from larger QC data sets.


Asunto(s)
Aprendizaje Automático , Estructura Molecular
2.
J Chem Inf Model ; 61(9): 4210-4223, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34387994

RESUMEN

Most machine learning applications in quantum-chemistry (QC) data sets rely on a single statistical error parameter such as the mean square error (MSE) to evaluate their performance. However, this approach has limitations or can even yield incorrect interpretations. Here, we report a systematic investigation of the two components of the MSE, i.e., the bias and variance, using the QM9 data set. To this end, we experiment with three descriptors, namely (i) symmetry functions (SF, with two-body and three-body functions), (ii) many-body tensor representation (MBTR, with two- and three-body terms), and (iii) smooth overlap of atomic positions (SOAP), to evaluate the prediction process's performance using different numbers of molecules in training samples and the effect of bias and variance on the final MSE. Overall, low sample sizes are related to higher MSE. Moreover, the bias component strongly influences the larger MSEs. Furthermore, there is little agreement among molecules with higher errors (outliers) across different descriptors. However, there is a high prevalence among the outliers intersection set and the convex hull volume of geometric coordinates (VCH). According to the obtained results with the distribution of MSE (and its components bias and variance) and the appearance of outliers, it is suggested to use ensembles of models with a low bias to minimize the MSE, more specifically when using a small number of molecules in the training set.


Asunto(s)
Algoritmos , Aprendizaje Automático , Sesgo
3.
Int J Biochem Cell Biol ; 128: 105848, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32927086

RESUMEN

The cell's resistance to cell death by adhesion loss to extracellular matrix (anoikis), contributes to tumor progression and metastasis. Various adhesion molecules are involved in the anoikis resistance, including the syndecan-4 (SDC4), a heparan sulfate proteoglycan (HSPG) present on the cell surface. Changes in the expression of SDC4 have been observed in tumor and transformed cells, indicating its involvement in cancer. In previous works, we demonstrated that acquisition of anoikis resistance resistance by blocking adhesion to the substrate up-regulates syndecan-4 expression in endothelial cells. This study investigates the role of SDC4 in the transformed phenotype of anoikis resistant endothelial cells. Anoikis-resistant endothelial cells (Adh1-EC) were transfected with micro RNA interference (miR RNAi) targeted against syndecan-4. The effect of SDC4 silencing was analyzed by real-time PCR, western blotting and immunofluorescence. Transfection with miRNA-SDC4 resulted in a sequence-specific decrease in syndecan-4 mRNA and protein levels. Furthermore, we observed a reduction in the number of heparan and chondroitin sulfate chains in the cell extract and culture medium. The SDC4 silencing led to downregulation of proliferative and invasive capacity and angiogenic abilities of anoikis-resistant endothelial cells. Compared with the parental cells (Adh1-EC), SDC4 silenced cells (SDC4 miR-Syn-4-1-Adh1-EC e miR-Syn-4-2-Adh1-EC) exhibited an increase in adhesion to collagen and laminin and also in the apoptosis rate. Moreover, transfection with miRNA-SDC4 caused a decrease in the number of cells in the S phase of the cell cycle. This is accompanied by an increase in the heparan sulfate synthesis after 12 h of simulation with fetal calf serum (FCS). SDC4 silencing cells are more dependent of growth factors present in the FCS to synthesize heparan sulfate than parental cells. Similar data were obtained for the wild-type cell line (EC). Our results indicated that downregulation of SDC4 expression reverses the transformed phenotype of anoikis resistant endothelial cells. These and other findings suggest that syndecan-4 is suitable for pharmacological intervention, making it an attractive target for cancer therapy.


Asunto(s)
Anoicis , Células Endoteliales/metabolismo , MicroARNs/metabolismo , Interferencia de ARN , Sindecano-4/biosíntesis , Animales , MicroARNs/genética , Conejos , Sindecano-4/genética
4.
Epidemiol Serv Saude ; 29(4): e2020427, 2020.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-32844918

RESUMEN

OBJECTIVE: To analyze the frequency of sadness, nervousness, and sleep disorders during the COVID-19 pandemic in Brazil, identifying the most affected demographic segments. METHODS: This was a cross-sectional study using an online questionnaire answered by adults and elderly people to collect information on living conditions, health and health-related behaviors. Prevalence rates and prevalence ratios adjusted for age and sex were estimated. RESULTS: The data on 45,161 Brazilian respondents showed that during the pandemic 40.4% (95%CI 39.0;41.8) frequently felt sad or depressed and 52.6% (95%CI 51.2;54.1) frequently felt anxious or nervous; 43.5% (95%CI 41.8;45.3) reported the onset of sleep problems and 48.0% (95%CI 45.6;50.5) had a prior sleep problem that had become worse. Frequent sadness and nervousness, as well as change in sleep patterns were higher in young adults, women and those with a history of depression. CONCLUSION: The high prevalence found indicates the need to guarantee the provision of services for mental health and quality of sleep that are adapted to the pandemic context.


Asunto(s)
Ansiedad/epidemiología , Betacoronavirus , Infecciones por Coronavirus/psicología , Depresión/epidemiología , Neumonía Viral/psicología , Tristeza , Trastornos del Sueño-Vigilia/epidemiología , Adulto , Distribución por Edad , Anciano , Brasil/epidemiología , COVID-19 , Intervalos de Confianza , Infecciones por Coronavirus/epidemiología , Estudios Transversales , Femenino , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/epidemiología , Prevalencia , SARS-CoV-2 , Adulto Joven
5.
Epidemiol. serv. saúde ; 29(4): e2020427, 2020. tab
Artículo en Inglés, Portugués | LILACS | ID: biblio-1124771

RESUMEN

Objetivo: Analisar a frequência de tristeza, nervosismo e alterações do sono durante a pandemia de COVID-19 no Brasil, identificando os segmentos demográficos mais afetados. Métodos: Estudo transversal, com questionário aplicado via web a adultos e idosos, coletando informações sobre condições de vida, saúde e comportamento. Foram estimadas prevalências e razões de prevalências ajustadas por idade e sexo. Resultados: De 45.161 brasileiros respondentes, verificou-se que, durante a pandemia, 40,4% (IC95% 39,0;41,8) se sentiram frequentemente tristes ou deprimidos, e 52,6% (IC95% 51,2;54,1) frequentemente ansiosos ou nervosos; 43,5% (IC95% 41,8;45,3) relataram início de problemas de sono, e 48,0% (IC95% 45,6;50,5) problema de sono preexistente agravado. Tristeza, nervosismo frequentes e alterações do sono estiveram mais presentes entre adultos jovens, mulheres e pessoas com antecedente de depressão. Conclusão: As elevadas prevalências encontradas indicam a necessidade de garantir a provisão de serviços de atenção à saúde mental e à qualidade do sono, adaptados ao contexto pandêmico.


Objetivo: Analizar la frecuencia de tristeza, nerviosismo y trastornos del sueño durante la pandemia de COVID-19 en Brasil. Métodos: Estudio transversal, con cuestionario aplicado a adultos y ancianos vía web, que recopiló información sobre las condiciones de vida, la salud y los comportamientos de salud. Se estimaron prevalencias y razones de prevalencia que se ajustaron por edad y sexo. Resultados: Con datos de 45.161 encuestados, se encontró que el 40,4% (IC95% 41,4; 46,7) de los brasileños a menudo se sentía triste o deprimido y el 52,6% (IC95% 51,2; 54,1) a menudo ansioso o nervioso; el 43,5% (IC95% 41,8; 45,3) comenzó a tener trastornos de sueño y el 48,0% (IC95% 45,6; 50,5) tuvo trastorno de sueño previo agravado. La tristeza, el nerviosismo y los trastornos del sueño fueron mucho más intensos en adultos jóvenes, mujeres y personas con antecedentes de depresión. Conclusión: Las altas prevalencias encontradas indican la necesidad de garantizar la provisión de servicios a la salud mental y a la calidad del sueño, de forma adaptada al contexto pandémico.


Objective: To analyze the frequency of sadness, nervousness, and sleep disorders during the COVID-19 pandemic in Brazil, identifying the most affected demographic segments. Methods: This was a cross-sectional study using an online questionnaire answered by adults and elderly people to collect information on living conditions, health and health-related behaviors. Prevalence rates and prevalence ratios adjusted for age and sex were estimated. Results: The data on 45,161 Brazilian respondents showed that during the pandemic 40.4% (95%CI 39.0;41.8) frequently felt sad or depressed and 52.6% (95%CI 51.2;54.1) frequently felt anxious or nervous; 43.5% (95%CI 41.8;45.3) reported the onset of sleep problems and 48.0% (95%CI 45.6;50.5) had a prior sleep problem that had become worse. Frequent sadness and nervousness, as well as change in sleep patterns were higher in young adults, women and those with a history of depression. Conclusion: The high prevalence found indicates the need to guarantee the provision of services for mental health and quality of sleep that are adapted to the pandemic context.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Ansiedad/epidemiología , Trastornos del Sueño-Vigilia/epidemiología , Infecciones por Coronavirus/psicología , Infecciones por Coronavirus/epidemiología , Depresión/epidemiología , Brasil/epidemiología , Salud Mental/estadística & datos numéricos , Estudios Transversales , Pandemias , Tristeza/psicología
6.
J. oral res. (Impresa) ; 8(3): 177-184, jul. 31, 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1145334

RESUMEN

Aim: To determine the oral health behaviors, the prevalence of dental injuries, the level of information about first-aid procedures in the case of dental avulsion and the mouthguard awareness in a sample of Portuguese athletes. Materials and Methods: Cross-sectional researchamong 1,048 athletes from the district of Viseu, Portugal. A self-administered questionnaire included demographic data and questions about: I) oral hygiene habits, II) occurrence of orofacial trauma, III) use of mouthguards and IV) athletes' knowledge regarding first-aid management in case of dental avulsion was given. The comparison between different variables was made by Chi-square test with level of significant set at p-value ≤0.05. Results: The mean age of the sample (76.24% male) was 18.14±8.17 years. Overall, the results demonstrated a low use of dental floss (25.48%) and a high number of athletes (21.94%) that had not visited a dentist in more than a year. The prevalence of dental trauma was 5.06% and the most common dental injuries experienced by athletes were crown fractures (60.38%). Nearly half of the participants (45.23%) reported not knowing how to act following a dental avulsion. The rate of mouthguard use was very low (9.73%). There was a significant relationship between the prevalence of dental injuries and the use of mouthguards (p=0.000; Cramér's V=0.145). Conclusion: The prevalence of dental trauma in our population was low. A low number of athletes use a mouthguard and there is a lack of knowledge concerning dental trauma issues. Prevention programs and promoting actions among this population are important and should be adopted.


Objetivo: Determinar los comportamientos de salud bucal, la prevalencia delesiones dentales, el nivel de información sobre los procedimientos de primeros auxilios en el caso de la avulsión dental y el conocimiento de los protectores bucales en una muestra de atletas portugueses. Materiales y métodos: estudio transversal de 1048 atletas del distrito de Viseu, Portugal. Se utilizó un cuestionario auto administrado que incluyó datos demográficos y preguntas sobre: I) hábitos de higiene bucal, II) ocurrencia de traumatismos orofaciales, III) uso de protectores bucales y IV) conocimiento de los atletas sobre el manejo de primeros auxilios en caso de avulsión dental. La comparación entre diferentes variables se realizó mediante la prueba de chi-cuadrado con el nivel de significancia establecido en p≤0.05. Resultados: La edad promedia de la muestra (76,24% hombres) fue de 18,14±8,17 años. En general, los resultados demostraron un bajo uso de hilo dental (25,48%) y un alto número de atletas (21,94%) que no habían visitado un dentista en más de un año. La prevalencia de trauma dental fue de 5,06% y las lesiones dentales más comunes que experimentaron los atletas fueron las fracturas de corona (60,38%). Casi la mitad de los participantes (45,23%) informaron que no sabían cómo actuar después de una avulsión dental. La tasa de uso de protectores bucales fue muy baja (9,73%). Hubo una relación significativa entre la prevalencia de lesiones dentales y el uso de protectores bucales (p=0,000; V de Cramer=0,145). Conclusión: la prevalencia de trauma dental en nuestra población fue baja. Un número bajo de atletas usa un protector bucal y hay una falta de conocimiento sobre temas de trauma dental. Programas de prevención y acciones de promoción entre esta población son importantes y deben ser adoptados.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Traumatismos en Atletas , Salud Bucal , Protectores Bucales , Portugal , Distribución de Chi-Cuadrado , Odontología Preventiva , Prevalencia , Estudios Transversales , Encuestas y Cuestionarios , Traumatismos de los Dientes/etiología , Atletas
7.
Environ Sci Pollut Res Int ; 24(32): 25221-25232, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28929286

RESUMEN

The advancement of technology and development of new electronic and electrical equipment with a reduced life cycle has increased the need for the disposal of them (called Waste of Electric and Electronic Equipment or simply e-waste) due to defects presented during use, replacement of obsolete equipment, and ease of acquisition of new equipment. There is a lack of consumer awareness regarding the use, handling storage, and disposal of this equipment. In Brazil, the disposal of post-consumer waste is regulated by the National Solid Waste Policy, established by Law No. 12305 and regulated on the 23rd December 2010. Under this legislation, manufacturers and importers are required to perform a project for the Reverse Logistics of e-waste, though its implementation is not well defined. This work focuses on the verification of the sustainability of reverse logistics suggested by the legislation and the mandatory points, evaluating its costs and the possible financial gain with recycling of the waste. The management of reverse logistics and recycling of waste electrical and electronic equipment, or simply recycling of e-waste, as suggested by the government, will be the responsibility of the managing organization to be formed by the manufacturers/importers in Brazil.


Asunto(s)
Residuos Electrónicos , Administración de Residuos , Brasil , Residuos Electrónicos/análisis , Residuos Electrónicos/economía , Reciclaje , Eliminación de Residuos/economía , Residuos Sólidos , Administración de Residuos/economía , Administración de Residuos/legislación & jurisprudencia
8.
Arq. bras. cardiol ; Arq. bras. cardiol;109(3): 231-240, Sept. 2017. graf
Artículo en Inglés | LILACS | ID: biblio-887921

RESUMEN

Abstract Background: Due to the nature of the percutaneous prosthesis deployment process, a variation in its final position is expected. Prosthetic valve placement will define the spatial location of its effective orifice in relation to the aortic annulus. The blood flow pattern in the ascending aorta is related to the aortic remodeling process, and depends on the spatial location of the effective orifice. The hemodynamic effect of small variations in the angle of inclination of the effective orifice has not been studied in detail. Objective: To implement an in vitro simulation to characterize the hydrodynamic blood flow pattern associated with small variations in the effective orifice inclination. Methods: A three-dimensional aortic phantom was constructed, reproducing the anatomy of one patient submitted to percutaneous aortic valve implantation. Flow analysis was performed by use of the Particle Image Velocimetry technique. The flow pattern in the ascending aorta was characterized for six flow rate levels. In addition, six angles of inclination of the effective orifice were assessed. Results: The effective orifice at the -4° and -2° angles directed the main flow towards the anterior wall of the aortic model, inducing asymmetric and high shear stress in that region. However, the effective orifice at the +3° and +5° angles mimics the physiological pattern, centralizing the main flow and promoting a symmetric distribution of shear stress. Conclusion: The measurements performed suggest that small changes in the angle of inclination of the percutaneous prosthesis aid in the generation of a physiological hemodynamic pattern, and can contribute to reduce aortic remodeling.


Resumo Fundamento: Devido à natureza do processo de liberação da prótese percutânea, é esperada uma variabilidade do posicionamento final da válvula. A localização da prótese irá definir a posição espacial do seu orifício efetivo em relação ao ânulo aórtico. O padrão do fluxo sanguíneo em aorta ascendente está relacionado ao processo de remodelamento aórtico, além de ser dependente da disposição espacial do orifício efetivo. O efeito hemodinâmico de pequenas variações na angulação do orifício efetivo ainda não foi estudado em detalhes. Objetivo: O objetivo do presente trabalho foi implementar uma simulação in vitro do fluxo sanguíneo para caracterização do padrão hidrodinâmico, associado a pequenas variações na inclinação do orifício efetivo. Métodos: Para esse fim, foi construído um fantoma aórtico tridimensional, que reproduziu a anatomia de um paciente submetido ao implante valvar percutâneo. A análise de fluxo foi realizada através da técnica de Velocimetria por Imagens de Partícula. O padrão de escoamento em aorta ascendente foi caracterizado para seis níveis de vazão de fluxo. Além disso, foram estudados seis inclinações do orifício efetivo. Resultados: O estudo demonstrou que o orifício efetivo nos ângulos -4° e -2° direcionaram o fluxo principal para a parede anterior do modelo aórtico, induzindo um cisalhamento assimétrico e elevado nessa região. Por outro lado, os ângulos +3° e +5° mimetizam o padrão fisiológico, centralizando o fluxo principal e promovendo uma distribuição simétrica do cisalhamento. Conclusão: As medições realizadas sugerem que pequenas alterações angulares na prótese percutânea auxiliam na geração de um padrão hemodinâmico fisiológico, podendo contribuir para menor remodelamento aórtico.


Asunto(s)
Humanos , Masculino , Anciano , Estenosis de la Válvula Aórtica/cirugía , Postura , Velocidad del Flujo Sanguíneo/fisiología , Resistencia al Corte/fisiología , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Impresión Tridimensional , Angiografía por Tomografía Computarizada , Modelos Anatómicos
9.
Arq Bras Cardiol ; 109(3): 231-240, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28793046

RESUMEN

Background: Due to the nature of the percutaneous prosthesis deployment process, a variation in its final position is expected. Prosthetic valve placement will define the spatial location of its effective orifice in relation to the aortic annulus. The blood flow pattern in the ascending aorta is related to the aortic remodeling process, and depends on the spatial location of the effective orifice. The hemodynamic effect of small variations in the angle of inclination of the effective orifice has not been studied in detail. Objective: To implement an in vitro simulation to characterize the hydrodynamic blood flow pattern associated with small variations in the effective orifice inclination. Methods: A three-dimensional aortic phantom was constructed, reproducing the anatomy of one patient submitted to percutaneous aortic valve implantation. Flow analysis was performed by use of the Particle Image Velocimetry technique. The flow pattern in the ascending aorta was characterized for six flow rate levels. In addition, six angles of inclination of the effective orifice were assessed. Results: The effective orifice at the -4° and -2° angles directed the main flow towards the anterior wall of the aortic model, inducing asymmetric and high shear stress in that region. However, the effective orifice at the +3° and +5° angles mimics the physiological pattern, centralizing the main flow and promoting a symmetric distribution of shear stress. Conclusion: The measurements performed suggest that small changes in the angle of inclination of the percutaneous prosthesis aid in the generation of a physiological hemodynamic pattern, and can contribute to reduce aortic remodeling.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Velocidad del Flujo Sanguíneo/fisiología , Postura , Resistencia al Corte/fisiología , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Anciano , Angiografía por Tomografía Computarizada , Humanos , Masculino , Modelos Anatómicos , Impresión Tridimensional
10.
J Dairy Res ; 82(4): 460-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26119656

RESUMEN

Streptococcus dysgalactiae is a bacterium that accounts for a notable proportion of both clinical and subclinical intramammary infections (IMIs). Thus, the present study explores the function of milk neutrophils and the lymphocyte profile in mammary glands naturally infected with Streptococcus dysgalactiae. Here, we used 32 culture-negative control quarters from eight clinically healthy dairy cows with low somatic cell counts and 13 S. dysgalactiae-infected quarters from six dairy cows. Using flow cytometry, we evaluated the percentage of milk monocytes/macrophages and neutrophils, expression of CD62L, CD11b and CD44 by milk neutrophils, the levels of intracellular reactive oxygen species (ROS) production and phagocytosis of Staphylococcus aureus by milk neutrophils, and neutrophil viability. Furthermore, the percentages of B cell (CD21(+)) and T lymphocyte subsets (CD3(+)/CD4(+)/CD8(-); CD3(+)/CD8(+)/CD4(-); and CD3(+)/CD8(-)/CD4(-)), and the expression of CD25 by T milk lymphocytes (CD3(+)) and T CD4(+) milk cells were also assessed by flow cytometry using monoclonal antibodies. The present study showed a higher SCC and percentage of milk neutrophils, and a decrease in the percentage of milk monocytes/macrophages from S. dysgalactiae-infected quarters when compared to uninfected ones. We also observed a higher expression of CD11b by milk neutrophils and a tendency toward a decrease in neutrophil apoptosis rate in S. dysgalactiae-infected quarters. In addition, the S. dysgalactiae-infected quarters had higher percentages of milk T cells (CD3(+)) and their subset CD3(+)CD8(+)CD4(-) cells. Overall, the present study provided new insights into S. dysgalactiae IMIs, including distinct lymphocyte profiles, and a tendency toward an inhibition of apoptosis in milk neutrophils.


Asunto(s)
Subgrupos Linfocitarios/fisiología , Leche/citología , Neutrófilos/fisiología , Infecciones Estreptocócicas/veterinaria , Streptococcus/clasificación , Animales , Anticuerpos Monoclonales , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos CD18/genética , Antígenos CD18/metabolismo , Bovinos , Femenino , Citometría de Flujo , Regulación de la Expresión Génica , Macrófagos/fisiología , Mastitis Bovina , Selectinas/genética , Selectinas/metabolismo , Infecciones Estreptocócicas/patología
11.
Vet Res ; 46: 2, 2015 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-25595200

RESUMEN

The effects of bovine leukemia virus (BLV) on the immune response have been extensively investigated; however, its effects on mammary gland immunity are only speculative. Although BLV has a tropism for B cells, it can affect both adaptive and innate immunities because these systems share many effector mechanisms. This scenario is the basis of this investigation of the effects of BLV on mammary gland immunity, which is largely dependent upon neutrophilic functions. Thus, the present study sought to examine neutrophilic functions and the lymphocyte profile in the milk of naturally BLV-infected cows. The viability of the milk neutrophils and the percentage of milk neutrophils that produced reactive oxygen species (ROS) or phagocytosed Staphylococcus aureus were similar between BLV-infected and BLV-uninfected dairy cows. Furthermore, the expression of CD62L and CD11b by the milk neutrophils and the percentage of milk neutrophils (CH138+ cells) that were obtained from the udder quarters of the BLV-infected cows were not altered. Conversely, the median fluorescence intensity (MFI) representing intracellular ROS production and the phagocytosis of S. aureus, the expression of CD44 by the milk neutrophils and the percentage of apoptotic B cells were lower in the milk cells from BLV-infected dairy cows, particularly those from animals with persistent lymphocytosis (PL). The lymphocyte subsets were not different among the groups, with the exception of the percentage of CD5-/CD11b- B cells, which was higher in the milk cells from BLV-infected cows, particularly those with PL. Thus, the present study provides novel insight into the implications of BLV infection for mammary gland immunity.


Asunto(s)
Linfocitos B/inmunología , Leucosis Bovina Enzoótica/inmunología , Subgrupos Linfocitarios/inmunología , Leche/citología , Neutrófilos/inmunología , Animales , Bovinos , Leucosis Bovina Enzoótica/patología , Leucosis Bovina Enzoótica/virología , Femenino , Virus de la Leucemia Bovina/inmunología , Glándulas Mamarias Animales/inmunología , Fagocitosis , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/fisiología
12.
Pesqui. vet. bras ; 35(1): 1-5, 01/2015. graf
Artículo en Inglés | VETINDEX | ID: vti-12536

RESUMEN

This study evaluated the expression of CD14, toll-like receptor (TLR) 2 and TLR4 on the surface of milk neutrophils in bovine mammary glands infected with Corynebacterium bovis. Here, we used 23 culture-negative control quarters with no abnormal secretion on the strip cup test and milk somatic cell count lower than 1x105 cells/mL, and 14 C. bovis infected quarters. The identification of neutrophils, as well as, the percentage of neutrophils that expressed CD14, TLR2 and TLR4 were analyzed by flow cytometry using monoclonal antibodies. The present study encountered no significant difference in the percentages of milk neutrophils that expressed TLR2 and TLR4 or in the expression of TLR4 by milk neutrophils. Conversely, a lower median fluorescence intensity of TLR2 in milk neutrophils was observed in C. bovis-infected quarters. The percentage of neutrophils that expressed CD14 and the median fluorescence intensity of CD14 in milk neutrophils was also lower in C. bovis-infected quarters.(AU)


O presente estudo objetivou avaliar alterações na expressão de CD14, e dos receptores do tipo toll (TLR) 2 e 4 na superfície de neutrófilos lácteos provenientes de glândulas mamárias infectadas por Corynebacterium bovis. O presente estudo utilizou 23 quartos negativos no exame bacteriológico, sem alterações na prova de fundo escuro e com contagem automática de células somáticas menor que 1 x105 células/mL, e 14 quartos mamários infectados por C. bovis A identificação de neutrófilos, assim como a porcentagem de neutrófilos lácteos que expressaram CD14, TLR2 e 4 foram avaliadas por citometria de fluxo utilizando anticorpos monoclonais. A porcentagem de neutrófilos que expressaram TLR2 e TLR4 nos quartos mamários infectados por C. bovis não diferiu dos quartos mamários sadios, assim como na expressão de TLR4. No entanto, a intensidade de fluorescência do TLR2 na superfície dos neutrófilos foi menor nos quartos mamários infectados por C. bovis. A porcentagem de neutrófilos que expressaram CD14 e a intensidade de fluorescência da molécula de CD14 foi menor na superfície dos neutrófilos lácteos dos quartos infectados por C. bovis.(AU)


Asunto(s)
Animales , Bovinos , Bovinos/inmunología , Corynebacterium/aislamiento & purificación , Receptores de Lipopolisacáridos/análisis , Receptor Toll-Like 2/análisis , Receptor Toll-Like 4/análisis , Mastitis Bovina/microbiología , Glándulas Mamarias Animales/fisiopatología
13.
Pesqui. vet. bras ; Pesqui. vet. bras;35(1): 1-5, 01/2015. graf
Artículo en Inglés | LILACS | ID: lil-746567

RESUMEN

This study evaluated the expression of CD14, toll-like receptor (TLR) 2 and TLR4 on the surface of milk neutrophils in bovine mammary glands infected with Corynebacterium bovis. Here, we used 23 culture-negative control quarters with no abnormal secretion on the strip cup test and milk somatic cell count lower than 1x105 cells/mL, and 14 C. bovis infected quarters. The identification of neutrophils, as well as, the percentage of neutrophils that expressed CD14, TLR2 and TLR4 were analyzed by flow cytometry using monoclonal antibodies. The present study encountered no significant difference in the percentages of milk neutrophils that expressed TLR2 and TLR4 or in the expression of TLR4 by milk neutrophils. Conversely, a lower median fluorescence intensity of TLR2 in milk neutrophils was observed in C. bovis-infected quarters. The percentage of neutrophils that expressed CD14 and the median fluorescence intensity of CD14 in milk neutrophils was also lower in C. bovis-infected quarters...


O presente estudo objetivou avaliar alterações na expressão de CD14, e dos receptores do tipo toll (TLR) 2 e 4 na superfície de neutrófilos lácteos provenientes de glândulas mamárias infectadas por Corynebacterium bovis. O presente estudo utilizou 23 quartos negativos no exame bacteriológico, sem alterações na prova de fundo escuro e com contagem automática de células somáticas menor que 1 x105 células/mL, e 14 quartos mamários infectados por C. bovis A identificação de neutrófilos, assim como a porcentagem de neutrófilos lácteos que expressaram CD14, TLR2 e 4 foram avaliadas por citometria de fluxo utilizando anticorpos monoclonais. A porcentagem de neutrófilos que expressaram TLR2 e TLR4 nos quartos mamários infectados por C. bovis não diferiu dos quartos mamários sadios, assim como na expressão de TLR4. No entanto, a intensidade de fluorescência do TLR2 na superfície dos neutrófilos foi menor nos quartos mamários infectados por C. bovis. A porcentagem de neutrófilos que expressaram CD14 e a intensidade de fluorescência da molécula de CD14 foi menor na superfície dos neutrófilos lácteos dos quartos infectados por C. bovis...


Asunto(s)
Animales , Bovinos , /análisis , Bovinos/inmunología , Corynebacterium/aislamiento & purificación , /análisis , /análisis , Glándulas Mamarias Animales/fisiopatología , Mastitis Bovina/microbiología
14.
Appl Opt ; 52(1): A397-409, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23292418

RESUMEN

The development of a specific holographic setup designed for providing three-dimensional imaging of micrometer particles in a very small volume inside a large air-flow facility is described. Study of a 1.5 mm(3) volume is made possible with the use of a microscope objective for magnification of the object field. Particles that are too small to be detected with a standard in-line hologram (about 1 µm in diameter or less) are illuminated laterally, and the 90° scattered field is magnified and recombined with a reference wave for in-line recording. A calibration procedure relates reconstruction space coordinates to measurement volume coordinates. Analysis of the results shows that particle images reconstruct with very good axial accuracy. Preliminary tests show that this approach should allow measurements of fluid velocity very close to the wall in a wind-tunnel flow.

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