2,996 research outputs found
Colon adenocarcinoma diagnosis in human samples by multicontrast nonlinear optical microscopy of hematoxylin and eosin stained histological sections
Combined multimodal nonlinear optical (NLO) microscopies were used to detect and quantify morphological changes associated with stroma and epithelial transformation in colon cancer. Our findings provide complementary information about tissue microstructure, displaying distinctive patterns between normal and malignant human colon. Additionally, we have demonstrated the usefulness of using fixed tissues for the disease diagnostic and prognostic. The present work provides a framework for using NLO techniques as a clinical diagnostic tool for human colon cancer. NLO metrics could be applied to other disorders, which are characterized by abnormal cell proliferation and collagen assembly.Fil: Adur, Javier Fernando. Universidad Nacional de Entre RÃos. Facultad de IngenierÃa; Argentina. National Institute of Science and Technology on Photonics Applied to Cell Biology; Brasil. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro de Investigaciones y Transferencia de Entre RÃos. Universidad Nacional de Entre RÃos. Centro de Investigaciones y Transferencia de Entre RÃos; ArgentinaFil: Bianchi, Mariana. Universidad Nacional de Entre RÃos. Facultad de IngenierÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Pelegati, Vitor B.. National Institute of Science and Technology on Photonics Applied to Cell Biology; BrasilFil: Viale, Silvia. Universidad Nacional de Entre RÃos. Facultad de IngenierÃa; ArgentinaFil: Izaguirre, MarÃa Fernanda. Universidad Nacional de Entre RÃos. Facultad de IngenierÃa; ArgentinaFil: Carvalho, Hernandes Faustino. Universidade Estadual de Campinas; BrasilFil: Cesar, Carlos L.. Universidade Estadual de Campinas; BrasilFil: Casco, Victor Hugo. Universidad Nacional de Entre RÃos. Facultad de IngenierÃa; Argentin
Nonlinear Microscopy Techniques: Principles and Biomedical Applications
Nonlinear optical microscopy techniques have emerged as a set of successful tools within the biomedical research field. These techniques have been successfully used to study autofluorescence signals in living tissues, structural protein arrays, and to reveal the presence of lipid bodies inside the tissular volume. In the first section, the nonlinear contrast technique foundations is described, and also, a practical approach about how to build and combine this setup on a single confocal system platform shall be provided. In the next section, examples of the usefulness of these approaches to detect early changes associated with the progression of different epithelial and connective tissular diseases are presented
La secuencia Neopaleozoica de la quebrada de Agua de Jagüel (Precordillera de Mendoza): edad y redefinición estratigráfica
Se propone la denominación de Formación Cordón de Jagüel para la sucesión pérmica de areniscas, pelitas y escasos conglomerados que forman la ladera occidental del Cordón de Agua de Jagüel en la Precordillera de Mendoza. Estas rocas descansan en discordancia sobre metasedimentitas de la Formación Villavicencio y son separadas por falla de areniscas, pelitas y diamictitas pertenecientes a la Formación Agua de Jagüel (Pennsylvaniano). En la Formación Cordón de Jagüel se han identificado seis asociaciones de facies sedimentarias. La asociación 1 está integrada mayormente por conglomerados polimÃcticos y areniscas gruesas de origen fluvial. El inicio de un ascenso relativo del nivel del mar aparece registrado en la asociación de facies 2, formada por areniscas y pelitas carbonosas depositadas en ambientes transicionales, probablemente estuarinos. La asociación de facies 3, compuesta por areniscas finas, indica el pasaje a un ambiente marino costero, mientras que la asociación de facies 4 incluye areniscas con paquetes de estratificación entrecruzada de gran escala y probablemente corresponde a ambientes subtidales con importante crecimiento de barras de arena de gran porte. Una progresiva somerización llevó a la depositación de pelitas carbonosas, areniscas finas e intercalaciones de margas (asociación de facies 5) en ambientes restringidos (albuferas). Finalmente, la asociación de facies 6 (pelitas laminadas y areniscas finas) indica un nuevo evento transgresivo. Restos de invertebrados marinos pertenecientes a la Biozona de Costatumulus y de palinofloras conteniendo Lueckisporites virkkiae Potonié y Klaus sugieren una edad pérmica temprana, probablemente cisuraliana tardÃa para la unidad.The neopaleozoic sequence of the Agua de Jagüel Creek (Precordillera de Mendoza): age and stratigraphic redefinition. The name of the Cordón de Jagüel Formation is proposed for Permian sandstones, mudstones and scarce conglomerates that form the western slope of the Cordón de Agua de Jagüel range in the Precordillera (Mendoza Province). These rocks unconformably overlie low-grade metamorphic rocks belonging to the Villavicencio Formation and are separated by a fault from sandstones, mudstones and diamictites of the Agua de Jagüel Formation (Pennsylvanian). Six facies association have been recognized in the Cordón de Jagüel Formation. The association 1 is composed of conglomerates and coarse-grained sandstones deposited in fluvial environment. The onset of a sea-level rise is recorded in the facies association 2, which is formed by sandstones and carbonaceous mudstones sedimented in transitional environments (estuarine?). Facies association 3 is made up by fine-grained sandstones indicating the transition to coastal marine settings while facies association 4, formed by large-scale cross-bedded sandstones, was very probably deposited in subtidal coastal environments. A progressive shallowing appears in the carbonaceous mudstones, fine-grained sandstones and marls forming the facies association 5 deposited in a transitional environment (lagoons). Finally, facies association 6 (shales and fine-grained sandstones) indicates a new sea level rise. Remains of the marine invertebrates belonging to the Costatumulus Biozone and palynofloras containing Lueckisporites virkkiae Potonié and Klaus suggest an early Permian age, probably late Cisuralian, for the unit.litic layer. Proximal non-amalgamated storm deposits are represented by thick sandy beds with hummocky cross stratification, bioclastic accumulations and ripples at the top intercalated with thin shaly levels. Distal storm deposits are thinly laminated o massive silty to sandy beds intercalated in shaly intervals.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Isbell, John L.. University of Wisconsin. Department of Geosciences; Estados UnidosFil: Ciccioli, Patricia Lucia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Taboada, Arturo Cesar. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Laboratorio de Investigaciones en Evolución y Biodiversidad; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentin
Comparison of morphological changes of corneal collagen fibers treated with collagen crosslinking agents using second harmonic generation images
Corneal cross-linking (CXL) is a common surgical procedure used to modify corneal biomechanics and stabilize keratoconus progression which is still under discussion. Its side effects, which are mostly related to anatomical unpredictability and stromal exposure, are the reason for the search for new CXL agents. In this work we have quantitatively evaluated the porcine corneal stroma architecture treated with collagen crosslinking agents such as riboflavin solutions and açai extract, using second harmonic generation microscopy. Aimed at evaluating the morphological changes in the corneal stroma after collagen crosslinking under a CXL chemical agent, a tubeness filter based Hessian matrix to obtain a 3D fiber characterization of the SHG images was applied. The results showed a curling effect and shortening of the collagen fibers treated with açai as compared to the control. They also showed a higher degree of clustering of the collagen fibers with larger empty spaces when compared to the other two groups. We believe that studies such as these presented in this paper are a good direct nondestructive and free labeling evaluation technique that allows the observation of morphologic features of corneas treated with new CXL agents.Fil: Zeitoune, Angel Alberto. Universidad Nacional de Entre RÃos. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática - Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática; ArgentinaFil: Bersanetti, PatrÃcia A.. Universidade Federal de Sao Paulo; BrasilFil: Schor, Paulo. Universidade Federal de Sao Paulo; BrasilFil: Erbes, Luciana Ariadna. Universidad Nacional de Entre RÃos. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática - Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática; ArgentinaFil: Cesar, Carlos L.. Instituto Nacional de Fotônica Aplicada à Biologia Celular; Brasil. Universidade Federal do Ceara; BrasilFil: Adur, Javier Fernando. Universidad Nacional de Entre RÃos. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática - Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en BioingenierÃa y Bioinformática; Argentin
Oximetry signal processing identifies REM sleep-related vulnerability trait in asthmatic children
Rationale. The sleep-related factors that modulate the nocturnal worsening of asthma in children are poorly understood. This study addressed the hypothesis that asthmatic children have a REM sleep-related vulnerability trait that is independent of OSA.
Methods. We conducted a retrospective cross-sectional analysis of pulse-oximetry signals obtained during REM and NREM sleep in control and asthmatic children (n=134). Asthma classification was based on preestablished clinical criteria. Multivariate linear regression model was built to control for potential confounders (significance level p ≤ 0.05).
Results. Our data demonstrated that (1) baseline nocturnal respiratory parameters were not significantly different in asthmatic versus control children, (2) the maximal % of SaO2 desaturation during REM, but not during NREM, was significantly higher in asthmatic children, and (3) multivariate analysis revealed that the association between asthma and REM-related maximal % SaO2 desaturation was independent of demographic variables.
Conclusion. These results demonstrate that children with asthma have a REM-related vulnerability trait that impacts oxygenation independently of OSA. Further research is needed to delineate the REM sleep neurobiological mechanisms that modulate the phenotypical expression of nocturnal asthma in children
Influência da função pulmonar e da força muscular na capacidade funcional de portadores de doença pulmonar obstrutiva crónica = The influence of lung function and muscular strength on the functional capacity of chronic obstructive pulmonary disease patients
Objectivo : Determinar que variável entre o volume expirado forçado no primeiro segundo (VEF1), a pressão
parcial do oxigénio no sangue arterial (PaO2), a hipoxemia nocturna e a força muscular do quadricÃpite femoral pode predizer a distância percorrida no teste de caminhada de seis minutos (TC6) em doentes com DPOC.
Doentes e métodos : Um estudo observacional do tipo
transversal, envolvendo trinta doentes encaminhados a
um programa de reabilitação pulmonar de um hospital
universitário. A função pulmonar foi avaliada por espirometria, gasometria arterial e oximetria nocturna.
A função muscular pela força muscular do quadricÃpite femoral e a avaliação da capacidade funcional pelo TC6.
Resultados : A análise de regressão bivariada mostrou
que a força do quadricÃpite femoral foi a única variá-
vel que se mostrou estatisticamente significativa
(p = 0,002) em predizer a distância, sendo responsá-
vel por 38% da variância do TC6. Para essas variáveis
a relação estabelecida estatisticamente foi que para
cada quilo de força do quadricÃpite femoral, os doentes
caminharam 5,9 metros no TC6.
Conclusão : Os resultados indicam a importância da
força muscular do MI em testes de esforço submáximo.
Entre as variáveis estudadas, apenas a força muscular
do quadricÃpite femoral pôde predizer a distância
percorrida no TC6 em portadores de doença
pulmonar obstrutiva crónica.
Aim : To determine which variable (forced expiratory volume in 1 second (FEV1), partial pressure of oxygen in arterial blood (PaO2), nocturnal hypoxaemia and muscular strength of femoral quadriceps) can predict the distance walked in the six-minute walk test (6MWT) by COPD patients.
Methods : A cross-sectional and observational study of thirty patients referred to a pulmonary rehabilita tion programme at a university hospital. Lung function was evaluated by spirometry, arterial blood gas analysis and nocturnal oximetry. Muscle function was evaluated by quadriceps strength and functional capacity by the 6MWT.
Results : Bivariate regression analysis showed that quadriceps strength, was the only variable to correlate significantly with the distance walked in the 6MWT (p=0.002), accounting for 38% of the 6MWT variance. The statistical relationship established for these variables was 1kg of quadriceps strength equalled 5.9 metres walked in the 6MWT.
Conclusions : Our results showed the importance of lower limb muscle strength in submaximal exercise testing. We conclude that femoral quadriceps muscle strength is the only one of the variables studied which can predict the distance COPD patients walk in the 6MWT
Recognition Of Serous Ovarian Tumors In Human Samples By Multimodal Nonlinear Optical Microscopy.
We used a multimodal nonlinear optics microscopy, specifically two-photon excited fluorescence (TPEF), second and third harmonic generation (SHG∕THG) microscopies, to observe pathological conditions of ovarian tissues obtained from human samples. We show that strong TPEF + SHG + THG signals can be obtained in fixed samples stained with hematoxylin and eosin (H&E) stored for a very long time, and that H&E staining enhanced the THG signal. We then used the multimodal TPEF-SHG-THG microscopies in a stored file of H&E stained samples of human ovarian cancer to obtain complementary information about the epithelium∕stromal interface, such as the transformation of epithelium surface (THG) and the overall fibrillary tissue architecture (SHG). This multicontrast nonlinear optics microscopy is able to not only differentiate between cancerous and healthy tissue, but can also distinguish between normal, benign, borderline, and malignant specimens according to their collagen disposition and compression levels within the extracellular matrix. The dimensions of the layers of epithelia can also be measured precisely and automatically. Our data demonstrate that optical techniques can detect pathological changes associated with ovarian cancer.1609601
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