55 research outputs found

    Blind color deconvolution, normalization, and classification of histological images using general super Gaussian priors and Bayesian inference

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    This work was sponsored in part by the Agencia Es-tatal de Investigacion under project PID2019-105142RB-C22/AEI/10.13039/50110 0 011033, Junta de Andalucia under project PY20_00286,and the work by Fernando Perez-Bueno was spon-sored by Ministerio de Economia, Industria y Competitividad un-der FPI contract BES-2017-081584. Funding for open access charge: Universidad de Granada/CBUA.Background and Objective: Color variations in digital histopathology severely impact the performance of computer-aided diagnosis systems. They are due to differences in the staining process and acquisition system, among other reasons. Blind color deconvolution techniques separate multi-stained images into single stained bands which, once normalized, can be used to eliminate these negative color variations and improve the performance of machine learning tasks. Methods: In this work, we decompose the observed RGB image in its hematoxylin and eosin components. We apply Bayesian modeling and inference based on the use of Super Gaussian sparse priors for each stain together with prior closeness to a given reference color-vector matrix. The hematoxylin and eosin components are then used for image normalization and classification of histological images. The proposed framework is tested on stain separation, image normalization, and cancer classification problems. The results are measured using the peak signal to noise ratio, normalized median intensity and the area under ROC curve on five different databases. Results: The obtained results show the superiority of our approach to current state-of-the-art blind color deconvolution techniques. In particular, the fidelity to the tissue improves 1,27 dB in mean PSNR. The normalized median intensity shows a good normalization quality of the proposed approach on the tested datasets. Finally, in cancer classification experiments the area under the ROC curve improves from 0.9491 to 0.9656 and from 0.9279 to 0.9541 on Camelyon-16 and Camelyon-17, respectively, when the original and processed images are used. Furthermore, these figures of merits are better than those obtained by the methods compared with. Conclusions: The proposed framework for blind color deconvolution, normalization and classification of images guarantees fidelity to the tissue structure and can be used both for normalization and classification. In addition, color deconvolution enables the use of the optical density space for classification, which improves the classification performance.Agencia Es-tatal de Investigacion PID2019-105142RB-C22/AEI/10.13039/50110 0 011033Junta de Andalucia PY20_00286Ministerio de Economia, Industria y Competitividad under FPI BES-2017-081584Universidad de Granada/CBU

    Melanomas in the elderly: clinical and epidemiological features

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    El melanoma es un tumor muy agresivo derivado de los melanocitos con una incidencia creciente y unas tasas altas de mortalidad en la población anciana. Se ha diseñado un estudio retrospectivo para conocer las características clínicas y epidemiológicas de los melanomas intervenidos en la población de pacientes mayores de 65 años en el Hospital San Cecilio de Granada durante el año 2009. El valor medio del espesor de Breslow observado en los pacientes ancianos ha sido muy elevado (2,6 mm) lo que ensombrece el pronóstico de esta enfermedad. Es muy importante la sospecha diagnostica por parte de los médicos de atención primaria y geriatras para realizar una derivación precoz a unidades especializadas para iniciar un tratamiento adecuado.Melanoma is an aggressive tumor derived from melanocytes with increasing incidence and high mortality rates in the elderly population. We have designed a retrospective study to know the clinical and epidemiological features of melanoma in patients aged more than 65 years old undergoing surgery in Hospital Clinic in Granada (Spain) in 2009. Mean Breslow thickness observed in elderly patients has been very high (2.6 mm) which worsens prognosis of this disease. It is very important to the suspected diagnosis by primary care physicians and geriatricians for an early referral to specialized units to initiate appropriate treatments

    Characterization of the human ridged and non-ridged skin: a comprehensive histological, histochemical and immunohistochemical analysis

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    The structure of the human skin is directly dependent on its location and the mechanical forces to which it is subjected. In the present work, we have performed a comprehensive analysis of the human ridged and non-ridged skin to identify the differences and similarities between both skin types. For this purpose, human skin samples were obtained from dorsal hand skin (DHS), palmar hand skin (PHS), dorsal foot skin (DFS) and plantar foot skin (PFS) from the same cadaveric donors. Histological, histochemical and semiquantitative and quantitative immunohistochemical analyses were carried out to evaluate the epidermis, dermis and basement membrane. Results show that the epithelial layer of ridged skin had larger cell number and size than non-ridged skin for most strata. Melanocytes and Langerhans cells were more abundant in non-ridged skin, whereas Merkel cells were preferentially found in ridged skin. The expression pattern of CK5/6 was slightly differed between non-ridged and ridged skin. Involucrin expression was slightly more intense in non-ridged skin than in ridged skin. Collagen was more abundant in foot skin dermis than in hand skin, and in ridged skin as compared to non-ridged skin. Elastic fibers were more abundant in DHS. Biglycan was more abundant in foot skin than in hand skin. No differences were found for blood and lymphatic vessels. The basement membrane laminin was preferentially found in foot skin. These results revealed important differences at the epithelial, dermal and basement membrane levels that could contribute to a better knowledge of the human skin histology.This work was partially supported by Award no. AC17/00013 (NanoGSkin) by ISCIII thorough AES 2017 and within the EuroNanoMed framework

    Epithelial in vitro differentiation of human mesenchymal stem cells (hMSCs) from adipose tissue (AT) and bone marrow (BM): cellular characterization and study of HLA I and II expression

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    AGRADECIMIENTOS Laboratorio de Citogenética del servicio de Análisis Clínicos del Hospital Universitario Virgen de las Nieves. Servicio de Análisis Clínicos (Sección de Citometría/Biopatología tumoral) del Hos- pital Universitario Virgen de las Nieves.Introducción: Las células troncales mesenquimales derivadas de tejido adiposo o médula ósea constituyen uno de los tratamientos de terapia celular más utilizados en los ensayos clínicos actuales por su capacidad inmunomoduladora. Además, por su potencial de diferenciación a células epiteliales pueden ser utilizadas en ingeniería tisular incorporadas a tejidos artificiales como la piel o córnea, sustituyendo a las células epiteliales autólogas de estos tejidos. Es necesario realizar una correcta caracterización de estas células diferenciadas y estudiar el efecto de la diferenciación en la expresión del HLA de clase I y II. Objetivos: Caracterizar y realizar los controles de calidad GMP en dos líneas de células mesenquimales troncales humanas de distintos orígenes (tejido adiposo y médula ósea) tras diferenciarlas a células epiteliales in vitro, y analizar si se modifica la expresión de los marcadores HLA I y II antes y después del proceso diferenciador. Metodología: Se ha realizado el aislamiento y expansión de las dos líneas celulares de células mesenquimales troncales a partir del tejido fuente y se ha procedido a su diferenciación in vitro a células epiteliales mediante medios de cultivos suplementados con factores de crecimiento específico. Se han realizado controles de calidad siguiendo los requerimientos de las normas de correcta fabricación y se ha estudiado por citometría de flujo la expresión de HLA tipo I y II antes y después del proceso diferenciador. Finalmente se ha comprobado mediante estudio histológico e inmunohistoquímico las características de las células diferenciadas. Resultados: Se han aislado dos líneas de células mesenquimales troncales de tejido adiposo y médula ósea que cumplen los controles de calidad propuestos. Tras el proceso diferenciador in vitro, las células mesenquimales troncales humanas no expresan marcadores HLA (I y II) importantes en la respuesta inmune, pero sí expresan débilmente proteínas relacionadas con los principales estratos epiteliales (CK5, CK6 y CK14). Conclusión: La ausencia de expresión de marcadores de HLA I y II por citometría de flujo en las células diferenciadas favorecería su uso con carácter alogénico en la construcción de piel y córneas humanas por ingeniería de tejidos, sin embargo, son necesarios más estudios que confirmen estos resultados preliminares y protocolos que optimicen el proceso diferenciador in vitro de las células mesenquimales troncales.Background: Human mesenchymal stem cells derived from adipose tissue and bone marrow are one of the most common cell therapy procedures used in recent clinical trials due to their immunomodulation capacity. Furthermore, for their epithelial differentiation potential can be used in tissue engineering, incorporated in artificial tissues such as skin and cornea, replacing autologous epithelial cells. It is necessary to make a correct cellular characterization of differentiated cells and to study the effect in HLA I and II expression. Objetives: Characterization and quality controls under GMP conditions of in vitro differentiated human mesenchymal stem cells from different sources (adipose tissue and bone marrow) to epithelial lineage, and study of HLA I and II expression before and after differentiation. Methods: Isolation and expansion of two human mesenchymal stem cells lines from their tissues of origin and in vitro differentiation to epithelial cells using culture mediums supplemented with specific growth factors. Quality controls according Good Manufacturing Practices have been made and HLA I and II expression before and after differentiation have been studied. Finally, characteristics of differentiated cells have been demonstrated by histological and immunohistochemical analysis. Results: Two human mesenchymal stem cells lines from adipose tissue and bone marrow have been isolated complying with the proposed quality controls. After in vitro differentiation, human mesenchymal stem cells do not express HLA (I and II) markers, which are important in immune response, but weakly express proteins related to main epithelial layers of human skin (CK5, CK6 and CK14). Conclusion: The absence of expression of HLA I and II by flow cytometry in differentiated cells would promote the use of them with allogenic character to construct human skin and cornea by tissue engineering, however, more studies and protocols are required to confirm these preliminary results and to optimize in vitro differentiation of human mesenchymal stem cells.FIS ISC-III and FEDER PI13/0257

    PARP inhibition attenuates histopathological lesion in ischemia/reperfusion renal mouse model after cold prolonged ischemia

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    We test the hypothesis that PARP inhibition can decrease acute tubular necrosis (ATN) and other renal lesions related to prolonged cold ischemia/reperfusion (IR) in kidneys preserved at 4°C in University of Wisconsin (UW) solution. Material and Methods. We used 30 male Parp1+/+ wild-type and 15 male Parp10/0 knockout C57BL/6 mice. Fifteen of these wild-type mice were pretreated with 3,4-dihydro-5-[4-(1-piperidinyl)butoxyl]-1(2H)-isoquinolinone (DPQ) at a concentration of 15 mg/kg body weight, used as PARP inhibitor. Subgroups of mice were established (A: IR 45 min/6 h; B: IR + 48 h in UW solution; and C: IR + 48 h in UW solution plus DPQ). We processed samples for morphological, immunohistochemical, ultrastructural, and western-blotting studies. Results. Prolonged cold ischemia time in UW solution increased PARP-1 expression and kidney injury. Preconditioning with PARP inhibitor DPQ plus DPQ supplementation in UW solution decreased PARP-1 nuclear expression in renal tubules and renal damage. Parp10/0 knockout mice were more resistant to IR-induced renal lesion. In conclusion, PARP inhibition attenuates ATN and other IR-related renal lesions in mouse kidneys under prolonged cold storage in UW solution. If confirmed, these data suggest that pharmacological manipulation of PARP activity may have salutary effects in cold-stored organs at transplantation.Funding: This research was supported by CTS no. 138 Research Group and from the Carlos III Health Institute of the Spanish Ministery of Health and Consumer Affairs (Red de Investigación Renal, REDinREN 012/0021/0025). “FEDER una manera de hacer Europa”

    Expresión de la esmotelina en la piel normal y tumoral

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    La esmotelina que no ha sido estudiada en la piel, podría ser un marcador que permitiría determinar células musculares lisas con capacidad contráctil. Por otra parte, la esmotelina no ha sido valorada en los tumores musculares lisos, lesiones perivasculares y anomalías vasculares cutáneas. El objetivo principal de la presente tesis es establecer el fenotipo inmunohistoquímico de la piel normal y en situaciones patológicas, con especial referencia a la esmotelina. Partiendo de las estructuras musculares cutáneas que son positivas para la esmotelina, estudiaremos aquellos procesos tumorales o malformativos que reproducen a dichas estructuras. Para ello se aplicará un protocolo inmunohistoquímico que permita caracterizar los distintos procesos.Tesis Univ. Granada. Programa Oficial de Doctorado en: Avances en Biomedicina: nuevas tecnologías aplicadas a la investigación en los diferentes sistemas biológico
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