Biomechanical Finite Element Method Model of the Proximal Carpal Row and Experimental Validation

This research was funded by the Ministry of Education Grants DPI2017-83859-R, EQC2018-004508-P, and UNGR15-CE-3664; Ministry of Health Grants DTS15/00093 and PI16/00339; and Junta de Andalucia Grants, B-TEP-026-UGR18, IE2017-5537, P18-RT-1653, PI-0107-2017, and PIN-0030-2017.The Finite Element Method (FEM) models are valuable tools to create an idea of the behavior of any structure. The complexity of the joints, materials, attachment areas, and boundary conditions is an open issue in biomechanics that needs to be addressed. Scapholunate instability is the leading cause of wrist pain and disability among patients of all ages. It is needed a better understanding of pathomechanics to develop new effective treatments. Previous models have emulated joints like the ankle or the knee but there are few about the wrist joint. The elaboration of realistic computational models of the carpus can give critical information to biomedical research and surgery to develop new surgical reconstructions. Hence, a 3D model of the proximal carpal row has been created through DICOM images, making a reduced wrist model. The materials, contacts, and ligaments definition were made via open-source software to extract results and carry on a reference comparison. Thus, considering the limitations that a reduced model could carry on (unbalanced forces and torques), the stresses that result in the scapholunate interosseous ligament (SLIL) lead us to a bones relative displacement, which support the kinematics hypothesis in the literature as the distal carpal row moves as a rigid solid with the capitate bone. Also, experimental testing is performed, successfully validating the linear strength values of the scapholunate ligament from the literature.Ministry of Education Grants DPI2017-83859-R EQC2018-004508-P UNGR15-CE-3664Ministry of Health Grants DTS15/00093 PI16/00339Junta de Andalucia B-TEP-026-UGR18 IE2017-5537 P18-RT-1653 PI-0107-2017 PIN-0030-201

Histological characterization of the human scapholunate ligament

The scapholunate interosseous ligament (SLIL) plays a fundamental role in stabilizing the wrist bones, and its disruption is a frequent cause of wrist arthrosis and disfunction. Traditionally, this structure is considered to be a variety of fibrocartilaginous tissue and consists of three regions: dorsal, membranous and palmar. Despite its functional relevance, the exact composition of the human SLIL is not well understood. In the present work, we have analyzed the human SLIL and control tissues from the human hand using an array of histological, histochemical and immunohistochemical methods to characterize each region of this structure. Results reveal that the SLIL is heterogeneous, and each region can be subdivided in two zones that are histologically different to the other zones. Analysis of collagen and elastic fibers, and several proteoglycans, glycoproteins and glycosaminoglycans confirmed that the different regions can be subdivided in two zones that have their own structure and composition. In general, all parts of the SLIL resemble the histological structure of the control articular cartilage, especially the first part of the membranous region (zone M1). Cells showing a chondrocyte-like phenotype as determined by S100 were more abundant in M1, whereas the zone containing more CD73-positive stem cells was D2. These results confirm the heterogeneity of the human SLIL and could contribute to explain why certain zones of this structure are more prone to structural damage and why other zones have specific regeneration potential

Biofabrication of a Tubular Model of Human Urothelial Mucosa Using Human Wharton Jelly Mesenchymal Stromal Cells

Several models of bioartificial human urothelial mucosa (UM) have been described recently. In this study, we generated novel tubularized UM substitutes using alternative sources of cells. Nanostructured fibrin–agarose biomaterials containing fibroblasts isolated from the human ureter were used as stroma substitutes. Then, human Wharton jelly mesenchymal stromal cells (HWJSC) were used to generate an epithelial-like layer on top. Three differentiation media were used for 7 and 14 days. Results showed that the biofabrication methods used here succeeded in generating a tubular structure consisting of a stromal substitute with a stratified epithelial-like layer on top, especially using a medium containing epithelial growth and differentiation factors (EM), although differentiation was not complete. At the functional level, UM substitutes were able to synthesize collagen fibers, proteoglycans and glycosaminoglycans, although the levels of control UM were not reached ex vivo. Epithelial differentiation was partially achieved, especially with EM after 14 days of development, with expression of keratins 7, 8, and 13 and pancytokeratin, desmoplakin, tightjunction protein-1, and uroplakin 2, although at lower levels than controls. These results confirm the partial urothelial differentiative potential of HWJSC and suggest that the biofabrication methods explored here were able to generate a potential substitute of the human UM for future clinical use.CTS-115 Tissue Engineering Group and by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica, Ministry of Science and Innovation, Instituto de Salud Carlos III, grant FIS PI21/0981 (cofinanced by FEDER funds, European Union)

Generation of genipin cross-linked fibrin-agarose hydrogel tissue-like models for tissue engineering applications

Generation of biomimetic and biocompatible artificial tissues is the basic research objective for tissue engineering (TE). In this sense, the biofabrication of scaffolds that resemble the tissues’ extracellular matrix (ECM) is an essential aim in this field. Uncompressed and nanostructured fibrin-agarose hydrogels (FAH and NFAH respectively) emerged as promising scaffold in TE, but its structure and biomechanical properties must be improved in order to broad their TE applications. Here we generated and characterized novel membranelike models with increased structural and biomechanical properties based on the chemical cross-linking of FAH and NFAH with genipin (GP at 0.1, 0.25, 0.5 and 0.75%). Furthermore, scaffolds were subjected to rheological (G, G’, G” modulus), ultrastructural and ex vivo biocompatibility analyses. Results showed that all GP concentrations increased the stiffness (G) and especially the elasticity (G’) of FAH and NFAH. Ultrastructural analyses demonstrated that GP and nanostructuration of FAH allowed controlling the porosity of FAH. In addition, biological studies revealed that higher concentration of GP significantly decreased the cell viability. Finally, this study demonstrated the possibility to generate natural FAH and NFAH with improved structural and biomechanical properties by using GP. However, further in vivo studies are needed in order to demonstrate the biocompatibility, biodegradability and regeneration capability of these cross-linked scaffolds

Expanded Differentiation Capability of Human Wharton's Jelly Stem Cells Toward Pluripotency: A Systematic Review

This study was supported by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+I) of the Spanish Ministry of Economy and Competitiveness (Instituto de Salud Carlos III), grants FIS PI17/0391, PI18/331 and PI18/332 (co-financed by ERDF-FEDER, European Union).Human Wharton’s jelly stem cells (HWJSC) can be efficiently isolated from the umbilical cord, and numerous reports have demonstrated that these cells can differentiate into several cell lineages. This fact, coupled with the high proliferation potential of HWJSC, make them a promising source of stem cells for use in tissue engineering and regenerative medicine. However, their real potentiality has not been established to date. In the present study we carried out a systematic review to determine the multilineage differentiation potential of HWJSC. After a systematic literature search we selected 32 publications focused on the differentiation potential of these cells. Analysis of these studies showed that HWJSC display expanded differentiation potential towards some cell types corresponding to all three embryonic cell layers (ectodermal, mesodermal and endodermal), which is consistent with their constitutive expression of key pluripotency markers such as OCT4, SOX2 and NANOG, and the embryonic marker SSEA4. We conclude that HWJSC can be considered cells in an intermediate state between multipotentiality and pluripotentiality, since their proliferation capability is not unlimited and differentiation to all cell types has not been demonstrated thus far. These findings support the clinical use of HWJSC for the treatment of diseases affecting not only mesoderm-type tissues, but also other cell lineages.Spanish Ministry of Economy and Competitiveness FIS PI17/0391, PI18/331, PI18/332ERDF-FEDER, European Unio

Experimental study of cardiac innervation in the cat after right stellectomy

En el presente trabajo se estudia, mediante degeneración walleriana y con tinciones argénticas de Gros, la distribución de la inervación simpática en las distintas áreas del corazón del gato (Felis silvestris catus), tras realizar simpatectomías derechas (estelectomías). Estas intervenciones se realizaron por vía anterior hasta llegar al ganglio estrellado. Tras analizar el material encontramos fibras nerviosas mielínicas degeneradas en: el área del pedículo arterial, en la zona de desembocadura de la vena cava superior y en las redes perivasculares del tabique interauricular de la aurícula derecha y del ventrículo derecho, y, en menor cantidad, encontramos, fibras degeneradas, en la zona del seno coronario, tabique interventricular y aurícula y ventrículo izquierdo.In the present study, Wallerian degeneration and Gros silver staining were used to investigate the distribution of sympathetic innervation in different areas of the heart of cat (Felis silvestris catus) after performing right sympathectomy (stellectomy). An anterior surgical approach was used to reach the stellate ganglion. Analysis of the material revealed degenerated myelin nerve fibres in artery pedicle area, area of the opening of the vena cava superior, and perivascular networks of the interatrial wall of the right atrium and right ventricle and showed, in smaller amounts, degenerated fibres in the coronary sinus area, ventricular and atrial wall and left ventricle

Development of secretome‑based strategies to improve cell culture protocols in tissue engineering

This study was supported by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tec- nológica (I + D + I) of the Spanish Ministry of Science and Innovation (Instituto de Salud Carlos III), grants FIS PI18/0331, FIS PI21/0980, FIS PI18/0332, FIS PI20/0317, ICI19/00024 and ICI21/00010, and by grants PE-0395- 2019 and PI-0442-2019 from the Consejería de Salud y Familias, Junta de Andalucía, Spain. Additional support was provided through grant B-CTS-450-UGR20 (proyectos de I + D + i en el marco del Programa Operativo FEDER Andalucía 2014–2020, University of Granada and Consejería de Transformación Económica, Industria, Conocimiento y Universidades), and cofinancing was provided from the European Regional Development Fund (ERDF) through the “Una manera de hacer Europa” program.The online version contains supplementary material available at https://doi. org/10. 1038/s41598-022-14115-yAdvances in skin tissue engineering have promoted the development of artificial skin substitutes to treat large burns and other major skin loss conditions. However, one of the main drawbacks to bioengineered skin is the need to obtain a large amount of viable epithelial cells in short periods of time, making the skin biofabrication process challenging and slow. Enhancing skin epithelial cell cultures by using mesenchymal stem cells secretome can favor the scalability of manufacturing processes for bioengineered skin. The effects of three different types of secretome derived from human mesenchymal stem cells, e.g. hADSC‑s (adipose cells), hDPSC‑s (dental pulp) and hWJSC‑s (umbilical cord), were evaluated on cultured skin epithelial cells during 24, 48, 72 and 120 h to determine the potential of this product to enhance cell proliferation and improve biofabrication strategies for tissue engineering. Then, secretomes were applied in vivo in preliminary analyses carried out on Wistar rats. Results showed that the use of secretomes derived from mesenchymal stem cells enhanced currently available cell culture protocols. Secretome was associated with increased viability, proliferation and migration of human skin epithelial cells, with hDPSC‑s and hWJSC‑s yielding greater inductive effects than hADSC‑s. Animals treated with hWJSC‑s and especially, hDPSC‑s tended to show enhanced wound healing in vivo with no detectable side effects. Mesenchymal stem cells derived secretomes could be considered as a promising approach to cell‑free therapy able to improve skin wound healing and regeneration.Spanish Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I + D + I) of the Spanish Ministry of Science and Innovation (Instituto de Salud Carlos III) FIS PI18/0331, FIS PI21/0980, FIS PI18/0332, FIS PI20/0317, ICI19/00024, ICI21/00010Junta de Andalucia PE-0395-2019, PI-0442-2019Proyectos de I + D + i en el marco del Programa Operativo FEDER Andalucia , University of Granada and Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades B-CTS-450-UGR20European Commissio

Effects of Four Formulations of Prostaglandin Analogs on Eye Surface Cells. A Comparative Study

We evaluated the cytotoxic effects of four prostaglandin analogs (PGAs) used to treat glaucoma. First we established primary cultures of conjunctival stromal cells from healthy donors. Then cell cultures were incubated with different concentrations (0, 0.1, 1, 5, 25, 50 and 100%) of commercial formulations of bimatoprost, tafluprost, travoprost and latanoprost for increasing periods (5 and 30 min, 1 h, 6 h and 24 h) and cell survival was assessed with three different methods: WST-1, MTT and calcein/AM-ethidium homodimer-1 assays. Our results showed that all PGAs were associated with a certain level of cell damage, which correlated significantly with the concentration of PGA used, and to a lesser extent with culture time. Tafluprost tended to be less toxic than bimatoprost, travoprost and latanoprost after all culture periods. The results for WST-1, MTT and calcein/AM-ethidium homodimer-1 correlated closely. When the average lethal dose 50 was calculated, we found that the most cytotoxic drug was latanoprost, whereas tafluprost was the most sparing of the ocular surface in vitro. These results indicate the need to design novel PGAs with high effectiveness but free from the cytotoxic effects that we found, or at least to obtain drugs that are functional at low dosages. The fact that the commercial formulation of tafluprost used in this work was preservative-free may support the current tendency to eliminate preservatives from eye drops for clinical use.This study was supported by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+I) from the Spanish Ministry of Economy and Competitiveness (Instituto de Salud Carlos III), grants FIS PI11/1582 and FIS PI14/0955 (co-financed by FEDER funds, European Union) and by Grant P10-CTS-6060 from the Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucia, Spain (Proyectos de Excelencia)

Implementation of a Training Program in Advanced Life Support within map competence of future students of Medicine, University of Granada

Objetivo: Analizar la primera experiencia de formación en soporte vital avanzado (SVA) en estudiantes de medicina, incluyéndola como asignatura de libre configuración siguiendo las normas de la European Resuscitation Council. Metodología: Estudio observacional descriptivo transversal. Los datos se recogieron de los alumnos que participaron en el curso de SVA, como asignatura de libre configuración, realizado en la facultad de medicina de la Universidad de Granada. Se recogieron mediante encuesta variables sociodemográficas, variables de aspectos específicos de calidad del curso, así como la consideración de los alumnos ante la posibilidad de implantación del SVA en los estudios de Grado en la facultad de medicina. (Escala de puntuación= 1 mínimo- 5 máximo). Resultados: Se encuestaron a los 25 alumnos que asistieron al curso y su evaluación fue: Evaluación global del curso= 5,0, docentes participantes=4,8+ 0,3, material empleado=4,2+ 0,5 y las instalaciones= 3,7+ 0,6. Necesidad de la implantación de la formación en soporte vital avanzado en los estudios de Grado= 84% imprescindible y el 16% recomendable. Formación de los docentes que impartan esta asignatura= 4% Formación específica en urgencias y emergencias, 4% Formación específica en soporte vital y el 92% formación específica en soporte vital y metodología de la formación. Espacios docentes específicos para la formación en soporte vital = 56% imprescindible, 40% recomendable y el 4% opcional. Escogería la asignatura=100% de alumnos respondió que SI. Posible dotación de créditos=4% 8 créditos, 80% 6 créditos y el 16% se mostró indiferente. Elección del año académico a impartir la asignatura=52% en quinto y el 48% en sexto. Necesidad de reciclaje= el 100% de los alumnos respondieron SI. Conclusiones: El grado de satisfacción con la acción formativa es muy elevado, destacando la valoraciòn a los docentes. Los alumnos consideran imprescindible que los docentes sean expertos clínicos en la atención al paciente en situación de PCR, y además dispongan de formación específica en metodología de la formación aplicada a la enseñanza del soporte vital. Además consideran que el desarrollo de un mapa competencial específico en soporte vital debe estar incorporado al curriculum formativo de cualquier estudiante del Grado de Medicina.Objective: To analyze the first training experience in advanced life support (ALS) in medical students, including it as a free elective course following the rules of the European Resuscitation Council. Method: This is a cross-sectional observational study. Data were collected from the students who participated in the course of ALS, as free elective course, held at the Faculty of Medicine of the University of Granada. Dates were collected: sociodemographic, specific aspects of quality of the course, as well as consideration of the students at the possibility of implementation of SVA in graduate studies in the faculty of medicine. (Rating scale = 1, minimum 5 maximum).Results: The 25 students who attended the course and its evaluation was surveyed was: Overall Course Evaluation = 5.0, participating teachers = 4.8 + 0.3, material used = 4.2 + 0.5 = 3 facilities, 7 + 0.6. Need for the implementation of training in advanced life support in the Degree = 84 % essential and 16% recommended. Training of teachers to impart this course = 4 % Specific training in emergency , 4 % Specific training in life support and 92% specific training in life support and training methodologies . Specific teaching areas for training in life support = 56 % essential, 40 % and 4% recommended optional. Choose the course = 100 % of students answered YES. Possible allocation of credits = 4% 8 credits 6 credits 80 % and 16% were indifferent. Election of the academic year to teach the subject = 52% in the fifth and sixth 48 %. Need for recycling = 100% of the students answered YES. Conclusions: The degree of satisfaction with the training is very high, highlighting the valuation teachers. The students believe that teachers must be skilled in clinical patient care at-PCR, and also have specific training in training methodology applied to the teaching of life support. Also to consider developing a specific competence map in life support should be incorporated into the training curriculum for any student of Degree of Medicine

Predicting successful prosthetic rehabilitation in major lower-limb amputation patients: a 15-year retrospective cohort study

Objective: To determine and compare specific factors that could be associated and predictive with successful prosthetic rehabilitation in major lower-limb amputations. Methods: A 15-year long (2000-2014) retrospective observational cohort study was conducted. Two different criteria were used to define successful prosthetic rehabilitation: (1) the ability to walk at least 45 m, regardless of assistive devices; and (2) walking >45 m without other ambulatory aids than one cane (if required). Age, gender, comorbidities, cause and level of amputation, stump characteristics, ulcers in the preserved limb, and time between surgery and physical therapy were examined as predictors of successful prosthetic rehabilitation. Results: A total of 169 patients (61.60±15.9 years) were included. Regarding walking ability with or without walking aids, the presence of ulcers in the preserved limb was individually associated with failed prosthetic rehabilitation (p < 0.001), while being male (OR = 0.21; 95%CI = 0.06-0.80) and transtibial level of amputation (OR = 6.73; 95%CI = 1.92-23.64) were identified as independent predictors of failure and success, respectively. Regarding the criterion of successful rehabilitation, a shorter time until rehabilitation was individually associated with improved walking ability (p < 0.013), while failure could be predicted by comorbidities (OR = 0.48; 95%CI = 0.29---0.78) and age groups of 65---75 years old (OR = 0.19; 95%CI = 0.05-0.78) and over 75 years old (OR = 0.19; 95%CI = 0.04-0.91). Conclusions: Regarding walking ability with or without walking aids, male gender and transtibiallevel of amputation are independently associated with failure and success respectively, whereasolder age and comorbidities can predict failed prosthetic rehabilitation when assistive walking devices are considered. Future prospective cohort studies are needed to confirm these findings