Culture of Hoffa fat pad mesenchymal stem/stromal cells on microcarrier suspension in vertical wheel bioreactor for extracellular vesicle production.

BACKGROUND: Mesenchymal stromal cells (MSCs) are increasingly employed in regenerative medicine approaches for their immunomodulatory and anti-inflammatory properties, which are encoded in their secretome including extracellular vesicles (EVs). The Hoffa fat pad (HFP) located infrapatellarly harbours MSCs that could assist in tissue homeostasis in osteoarthritic joints. Intraarticular injection therapies based on blood products could modulate the populations of released HFP-MSC-EVs in a quantitative manner. METHODS: To obtain amounts of HFP-MSC-derived EVs that allow pre-clinical evaluation, suitable EV production systems need to be developed. This work investigates the release of EVs from primary HFP-MSCs cultivated in a 3D environment using microcarrier suspension culture in a vertical wheel bioreactor in comparison to conventional 2D culture. To simulate an intraarticular blood product therapy, cultures were treated with citrate-anticoagulated platelet-rich plasma (CPRP) or hyperacute serum (hypACT) before EV collection. HFP-MSC-EVs are enriched via ultrafiltration and characterised via Western Blot, nanoparticle tracking analysis in scatter as well as fluorescence mode. EV potency was determined via RT-qPCR analysing the expression of type II and X collagen (COL2 and COL10), as well as inducible nitric oxide synthase (iNOS) in primary OA chondrocytes. RESULTS: Blood product supplementation elevated HFP-MSC metabolic activity as determined via XTT assay over the course of 14 days. 3D culture resulted in a roughly 100-fold EV yield compared to 2D culture and elevated number of EVs released per cell. Total protein content correlated with the EV concentration. While typical EV marker proteins such as CD9, CD63 or Alix were detected in total protein extracts, CD9 and CD73 colocalised on individual EVs highlighting their cell origin. The type of blood product treatment did not affect the size or concentration of EVs obtained from HFP-MSCs. Assessing potency of 3D culture EVs in comparison to 2D EVs revealed superior biological activity with regard to inhibition of inflammation, inhibition of chondrocyte hypertrophy and induction of cartilage-specific ECM production. CONCLUSIONS: HFP-MSCs proliferate in presence of human blood products indicating that animal serum in culture media can be avoided in the future. The culture of HFP-MSCs in the employed bioreactor was successfully used to generate quantities of EVs that could allow evaluation of HFP-MSC-EV-mediated effects in pre-clinical settings. In addition, EV potency of 3D EVs is superior to EVs obtained in conventional 2D culture flasks.

Deceptive Seduction by Femme Fatale Fireflies and Its Avoidance by Males of a Synchronous Firefly Species (Coleoptera: Lampyridae).

Photuris female fireflies attract males of different firefly species by responding to their flashing signals; then, they try to capture and feed on them. This aggressive mimicry is considered a major selective pressure on the communication systems of the fireflies of the American continent. The intensity of this selective pressure is a function of its efficiency in prey capture. In this study, the rates of attraction and capture of males of the synchronous firefly Photinus palaciosi by the predatory females of Photuris lugubris are reported. Although the females attract numerous males, their hunting success is low. This result is consistent with the few previous measurements published. In agreement with the predicted coevolutionary race between predator and prey, behaviors consistent with predation avoidance in P. palaciosi and increasing prey encounters and prey deception by P. lugubris were observed.

Possible technical aspects involved in the development of GERD after sleeve gastrectomy: Surgical technique considerations.

Sleeve gastrectomy (SG) is the most common bariatric surgery worldwide and has shown to cause de novo or worsen symptoms of gastroesophageal reflux disease (GERD). Esophageal motility and physiology studies are mandatory in bariatric and foregut centers. The predisposing factors in post-SG patients are disruption of His angle, resection of gastric fold and gastric fundus, increased gastric pressure, resection of the gastric antrum, cutting of the sling fibers and pyloric spasm. There are symptomatic complications due to sleeve morphology as torsion, incisura angularis stenosis, kinking and dilated fundus. In this article, we present recommendations, surgical technique and patient selection flow diagram for SG and avoid de novo or worsening GERD.

Extracellular Vesicle Isolation and Characterization for Applications in Cartilage Tissue Engineering and Osteoarthritis Therapy.

Extracellular vesicles (EVs) have the capacity for use in cartilage tissue engineering by stimulating tissue repair and microenvironmental reprogramming. This makes them ideal candidates for treating focal cartilage defects and cartilage degeneration in osteoarthritis (OA). Observational studies have reported beneficial biological effects of EVs, such as inhibition of inflammation, enhanced extracellular matrix deposition, and reduced cartilage degradation. Isolation of EVs derived from different source materials such as conditioned cell culture media or biofluids is essential to attribute observed biological effects to EVs as genuine effectors. This chapter presents a density- and a size-based method as well as a combination of both for isolation of EVs from conditioned cell culture media or biofluids. In addition, three methods for characterization of isolated EVs are suggested based on physical properties, protein profiling, and ultrastructural morphology.

A unique cardiovascular presentation of Marfan syndrome.

We report a neonate with severe Marfan syndrome (MS), prenatally identified to have persistent atrial tachycardia, biventricular dysfunction, and an unusual structure within the atria. Detailed postnatal echocardiographic evaluation and cross-sectional imaging confirmed congenital pseudoaneurysm of the mitral-aortic intervalvular fibrosa. Emergent testing by next-generation sequencing identified a FBN1 pathological variant, key to establishing goals of care. To our knowledge, this is the first reported case of a congenital pseudoaneurysm of the mitral-aortic intervalvular fibrosa in MS.

Factors Associated with Inability to Discharge After Stage 1 Palliation for Single Ventricle Heart Disease: An Analysis of the National Pediatric Cardiology Quality Improvement Collaborative Database.

Patient-level characteristics associated with survival for single ventricle heart disease following initial staged palliation have been described. However, the impact of peri-operative events on hospital discharge has not been examined. To characterize patient-level characteristics and peri-operative events that were associated with inability to be discharged after Stage 1 palliation (S1P). Analysis of the National Pediatric Cardiology Quality Improvement Collaborative Dataset including patients who underwent a S1P procedure between 2016 and 2019 (Norwood or Hybrid Stage 1 procedure). We examined patient-level characteristics and peri-operative events as possible predictors of inability to discharge after S1P. We constructed multivariate logistic regression models examining post-S1P discharge and in-hospital mortality, adjusting for covariates. 843 patients underwent a S1P and 717 (85%) patients were discharged home or remained inpatient until Stage 2 for social but not medical concerns. Moderate or greater pre-operative atrioventricular valve regurgitation (odds ratio (OR) 4.6, 95% confidence interval (CI) 1.8-12), presence of high-risk pre-operative adverse events (OR 1.5, 95%CI 1.0-2.3), peri-operative events: temporary dialysis (OR 5.4, 95%CI 1.5-18.9), cardiac catheterization or cardiac surgery (OR 2.9, 95%CI 1.8-4.6), sepsis (OR 2.7, 95%CI 1.2-6.2), junctional tachycardia (OR 2.6, 95%CI 1.0-6.3), necrotizing enterocolitis (OR 2.6, 95%CI 1.3-5.2), ECMO (OR 2.5, 95%CI 1.4-4.3), neurological injury (OR 2.1, 95%CI 1.1-4.1), and re-intubation (OR 1.8, 95%CI 1.1-2.9) were associated with inability to discharge after Stage 1. Cardiac anatomical factors, pre-operative adverse events, post-operative re-intubation, post-operative ECMO, infectious complications, and unplanned catheter or surgical re-interventions were associated with inability to discharge after S1P. These findings suggest that quality improvement efforts aimed at reducing these peri-operative events may improve Stage 1 survival and likelihood of discharge.

Rheumatic Heart Disease in the United States: Forgotten But Not Gone: Results of a 10 Year Multicenter Review.

Background Recent evaluation of rheumatic heart disease (RHD) mortality demonstrates disproportionate disease burden within the United States. However, there are few contemporary data on US children living with acute rheumatic fever (ARF) and RHD. Methods and Results Twenty-two US pediatric institutions participated in a 10-year review (2008-2018) of electronic medical records and echocardiographic databases of children 4 to 17 years diagnosed with ARF/RHD to determine demographics, diagnosis, and management. Geocoding was used to determine a census tract-based socioeconomic deprivation index. Descriptive statistics of patient characteristics and regression analysis of RHD classification, disease severity, and initial antibiotic prescription according to community deprivation were obtained. Data for 947 cases showed median age at diagnosis of 9 years; 51% and 56% identified as male and non-White, respectively. Most (89%) had health insurance and were first diagnosed in the United States (82%). Only 13% reported travel to an endemic region before diagnosis. Although 96% of patients were prescribed secondary prophylaxis, only 58% were prescribed intramuscular benzathine penicillin G. Higher deprivation was associated with increasing disease severity (odds ratio, 1.25; 95% CI, 1.08-1.46). Conclusions The majority of recent US cases of ARF and RHD are endemic rather than the result of foreign exposure. Children who live in more deprived communities are at risk for more severe disease. This study demonstrates a need to improve guideline-based treatment for ARF/RHD with respect to secondary prophylaxis and to increase research efforts to better understand ARF and RHD in the United States.

Optimization of Lyophilized Hyperacute Serum (HAS) as a Regenerative Therapeutic in Osteoarthritis.

Hyperacute serum (HAS) is a blood derivative product that promotes the proliferation of various cell types and controls inflammation in vitro. The aim of this study is to investigate the regenerative potential of different formulations of HAS, including lyophilized and hyaluronic acid combined versions, to obtain a stable and standardized therapeutic in osteoarthritis (OA), which may be able to overcome the variability limitations of platelet-rich plasma (PRP). Primary human osteoarthritic chondrocytes were used for testing cellular viability and gene expression of OA-related genes. Moreover, a co-culture of human explants of cartilage, bone and synovium under inflammatory conditions was used for investigating the inflammatory control capacities of the different therapeutics. In this study, one formulation of lyophilized HAS achieved the high cell viability rates of liquid HAS and PRP. Gene expression analysis showed that HAS induced higher Col1a1 expression than PRP. Cytokine quantification from supernatant fluids revealed that HAS treatment of inflamed co-cultures significantly reduced levels of IL-5, IL-15, IL-2, TNFα, IL-7 and IL-12. To conclude, lyophilized HAS is a stable and standardized therapeutic with high potential in joint regeneration.

Regenerative Potential of Blood-Derived Products in 3D Osteoarthritic Chondrocyte Culture System.

Intra-articular injection of different types of blood-derived products is gaining popularity and clinical importance in the treatment of degenerative cartilage disorders such as osteoarthritis. The regenerative potential of two types of platelet-rich plasma (PRP), prepared in the presence of EDTA (EPRP) and citrate (CPRP) and an alternative blood product-hyperacute serum (hypACT) was evaluated using a 3D osteoarthritic chondrocyte pellet model by assessing the metabolic cell activity, cartilage-related gene expression and extracellular matrix deposition within the pellets. Chondrocyte viability was determined by XTT assay and it revealed no significant difference in metabolic activity of OA chondrocyte pellets after supplementation with different blood products. Nevertheless, the selection of blood products influenced the cartilage-related genes expression, ECM morphology and the tissue quality of pellets. Both PRP types had a different biological effect depending upon concentration and even though CPRP is widely used in clinics our assessment did not reveal good results in gene expression either tissue quality. HypACT supplementation resulted in superior cartilage-related genes expression together with tissue quality and seemed to be the most stable product since no remarkable changes were observed between the two different concentrations. All in all, for successful regenerative therapy, possible molecular mechanisms induced by blood-derived products should be always carefully investigated and adapted to the specific medical indications.

Effects of Extracellular Vesicles from Blood-Derived Products on Osteoarthritic Chondrocytes within an Inflammation Model.

Osteoarthritis (OA) is hallmarked by a progressive degradation of articular cartilage. One major driver of OA is inflammation, in which cytokines such as IL-6, TNF-α and IL-1ß are secreted by activated chondrocytes, as well as synovial cells-including macrophages. Intra-articular injection of blood products-such as citrate-anticoagulated plasma (CPRP), hyperacute serum (hypACT), and extracellular vesicles (EVs) isolated from blood products-is gaining increasing importance in regenerative medicine for the treatment of OA. A co-culture system of primary OA chondrocytes and activated M1 macrophages was developed to model an OA joint in order to observe the effects of EVs in modulating the inflammatory environment. Primary OA chondrocytes were obtained from patients undergoing total knee replacement. Primary monocytes obtained from voluntary healthy donors and the monocytic cell line THP-1 were differentiated and activated into proinflammatory M1 macrophages. EVs were isolated by ultracentrifugation and characterized by nanoparticle tracking analysis and Western blot. Gene expression analysis of chondrocytes by RT-qPCR revealed increased type II collagen expression, while cytokine profiling via ELISA showed lower TNF-α and IL-1ß levels associated with EV treatment. In conclusion, the inflammation model provides an accessible tool to investigate the effects of blood products and EVs in the inflammatory context of OA.

Functional repertoire of EV-associated miRNA profiles after lipoprotein depletion via ultracentrifugation and size exclusion chromatography from autologous blood products.

Cartilage breakdown, inflammation and pain are hallmark symptoms of osteoarthritis, and autologous blood products such as citrate-anticoagulated platelet-rich plasma (CPRP) or hyperacute serum (hypACT) have been developed as a regenerative approach to rebuild cartilage, inhibit inflammation and reduce pain. However, mechanisms of action of these blood derivatives are still not fully understood, in part due to the large number of components present in these medical products. In addition, the discovery of extracellular vesicles (EVs) and their involvement in intercellular communication mediated by cargo molecules like microRNAs (miRNAs) opened up a whole new level of complexity in understanding blood products. In this study we focused on the development of an isolation protocol for EVs from CPRP and hypACT that can also deplete lipoproteins, which are often co-isolated in EV research due to shared physical properties. Several isolation methods were compared in terms of particle yield from CPRP and hypACT. To gain insights into the functional repertoire conveyed via EV-associated miRNAs, we performed functional enrichment analysis and identified NFκB signaling strongly targeted by CPRP EV miRNAs, whereas hypACT EV miRNAs affect IL6- and TGFß/SMAD signaling.

Neonatal Cardiac Emergencies: A Multidisciplinary Simulation Curriculum for Neonatology and Pediatric Cardiology Fellows.

Introduction: Although care for neonates with cardiac disease is frequently provided by neonatologists and pediatric cardiologists, training in the multidisciplinary management of neonatal cardiac emergencies is not often included in fellowship training. We created a multidisciplinary simulation curriculum to address the skills needed for neonatal cardiac care. Methods: Neonatology and pediatric cardiology fellows participated in 1-hour simulations on 3 different days. They managed a neonate with: (1) cyanosis, (2) cardiogenic shock, and (3) an unstable arrhythmia. Using both remote consultation and bedside evaluation, the participants diagnosed and jointly established a management plan for the infant. During the debrief, facilitators reviewed the clinical decisions and multidisciplinary management skills of the participants. Participants completed pre- and postparticipation surveys to evaluate the curriculum's effect on their confidence in the management of neonatal cardiac disease. Results: Thirty-three paired survey responses from 20 participants (11 neonatology and 9 pediatric cardiology) reported a mean overall satisfaction score of 4.6 (SD = 0.7) based on a 5-point Likert scale. Postparticipation confidence scores improved significantly in: (1) the recognition of the signs of congenital heart disease (pre = 4.1, post = 4.5, p = .01), (2) differentiation of cardiac cyanosis from noncardiac cyanosis (pre = 3.9, post = 4.2, p = .05), and (3) confidence in discussing cardiac concerns with consultants (pre = 3.3, post = 4.1, p = .02). Discussion: This multidisciplinary simulation improved fellows' confidence in the management of neonates with cardiac disease and provided an opportunity to practice team work, remote consultation, and cross-disciplinary communication.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles - Silver Linings for Cartilage Regeneration?

As the world's population is aging, the incidence of the degenerative disease Osteoarthritis (OA) is increasing. Current treatment options of OA focus on the alleviation of the symptoms including pain and inflammation rather than on restoration of the articular cartilage. Cell-based therapies including the application of mesenchymal stromal cells (MSCs) have been a promising tool for cartilage regeneration approaches. Due to their immunomodulatory properties, their differentiation potential into cells of the mesodermal lineage as well as the plurality of sources from which they can be isolated, MSCs have been applied in a vast number of studies focusing on the establishment of new treatment options for Osteoarthritis. Despite promising outcomes in vitro and in vivo, applications of MSCs are connected with teratoma formation, limited lifespan of differentiated cells as well as rejection of the cells after transplantation, highlighting the need for new cell free approaches harboring the beneficial properties of MSCs. It has been demonstrated that the regenerative potential of MSCs is mediated by the release of paracrine factors rather than by differentiation into cells of the desired tissue. Besides soluble factors, extracellular vesicles are the major component of a cell's secretome. They represent novel mechanisms by which (pathogenic) signals can be communicated between cell types as they deliver bioactive molecules (nucleic acids, proteins, lipids) from the cell of origin to the target cell leading to specific biological processes upon uptake. This review will give an overview about extracellular vesicles including general characteristics, isolation methods and characterization approaches. Furthermore, the role of MSC-derived extracellular vesicles in in vitro and in vivo studies for cartilage regeneration will be summarized with special focus on transported miRNA which either favored the progression of OA or protected the cartilage from degradation. In addition, studies will be reviewed investigating the impact of MSC-derived extracellular vesicles on inflammatory arthritis. As extracellular vesicles are present in all body fluids, their application as potential biomarkers for OA will also be discussed in this review. Finally, studies exploring the combination of MSC-derived extracellular vesicles with biomaterials for tissue engineering approaches are summarized.

Characterization and Chondroprotective Effects of Extracellular Vesicles From Plasma- and Serum-Based Autologous Blood-Derived Products for Osteoarthritis Therapy.

Autologous blood products gain increasing interest in the field of regenerative medicine as well as in orthopedics, aesthetic surgery, and cosmetics. Currently, citrate-anticoagulated platelet-rich plasma (CPRP) preparations are often applied in osteoarthritis (OA), but more physiological and cell-free alternatives such as hyperacute serum (hypACT) are under development. Besides growth factors, blood products also bring along extracellular vesicles (EVs) packed with signal molecules, which open up a new level of complexity at evaluating the functional spectrum of blood products. Large proportions of EVs originated from platelets in CPRP and hypACT, whereas very low erythrocyte and monocyte-derived EVs were detected via flow cytometry. EV treatment of chondrocytes enhanced the expression of anabolic markers type II collagen, SRY-box transcription factor 9 (SOX9), and aggrecan compared to full blood products, but also the catabolic marker and tissue remodeling factor matrix metalloproteinase 3, whereas hypACT EVs prevented type I collagen expression. CPRP blood product increased SOX9 protein expression, in contrast to hypACT blood product. However, hypACT EVs induced SOX9 protein expression while preventing interleukin-6 secretion. The results indicate that blood EVs are sufficient to induce chondrogenic gene expression changes in OA chondrocytes, while preventing proinflammatory cytokine release compared to full blood product. This highlights the potential of autologous blood-derived EVs as regulators of cartilage extracellular matrix metabolism and inflammation, as well as candidates for new cell-free therapeutic approaches for OA.

Methylene Blue for Refractory Shock in Children: A Systematic Review and Survey Practice Analysis.

OBJECTIVES: Shock refractory to fluid and catecholamine therapy has significant morbidity and mortality in children. The use of methylene blue to treat refractory shock in children is not well described. We aim to collect and summarize the literature and define physicians' practice patterns regarding the use of methylene blue to treat shock in children. DESIGN: We conducted a systematic search of MEDLINE, Embase, PubMed, Web of Science, Cochrane for studies involving the use of methylene blue for catecholamine-refractory shock from database inception to 2019. Collected studies were analyzed qualitatively. To describe practice patterns of methylene blue use, we electronically distributed a survey to U.S.-based pediatric critical care physicians. We assessed physician knowledge and experience with methylene blue. Survey responses were quantitatively and qualitatively evaluated. SETTING: Pediatric critical and cardiac care units. PATIENTS OR SUBJECTS: Patients less than or equal to 25 years old with refractory shock treated with methylene blue. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One-thousand two-hundred ninety-three abstracts met search criteria, 139 articles underwent full-text review, and 24 studies were included. Studies investigated refractory shock induced by a variety of etiologies and found that methylene blue was generally safe and increased mean arterial blood pressure. There is overall lack of studies, low number of study patients, and low quality of studies identified. Our survey had a 22.5% response rate, representing 125 institutions. Similar proportions of physicians reported using (40%) or never even considering (43%) methylene blue for shock. The most common reasons for not using methylene blue were unfamiliarity with this drug, its proper dosing, and lack of evidentiary support. CONCLUSIONS: Methylene blue appears safe and may benefit children with refractory shock. There is a stark divide in familiarity and practice patterns regarding its use among physicians. Studies to formally assess safety and efficacy of methylene blue in treating pediatric shock are warranted.

Encuesta en población abierta respecto a términos relacionados con decisiones al final de la vida.

INTRODUCTION: Concepts related to end-of-life decisions, such as euthanasia, palliative care, advance directives and therapeutic obstinacy, are poorly understood by the general population, which, when facing a terminal situation, is not prepared to choose the best option. OBJECTIVE: Pilot study (n = 544) to find out what the open population understands about terms used in end-of-life situations in four cities of the Mexican Republic. METHOD: Survey via Internet with 18 questions about different terms. It was a descriptive, cross-sectional study. Statistical analysis was carried out. RESULTS: People older than 18 years who were not engaged in health-related professional activities were selected. CONCLUSIONS: Most terms related to end-of-life decisions were found not to be interesting to or understood by a part of the population. The least recognized term was therapeutic obstinacy (62.8%), and the most widely known, palliative care (91%); there was confusion between the terms euthanasia and assisted suicide (47.8%). Age and education level had more influence in the results, than other demographic variables.

INTRODUCCIÓN: Conceptos relacionados con las decisiones que se toman al final de la vida, como eutanasia, cuidados paliativos, voluntad anticipada y obstinación terapéutica son poco comprendidos por la población en general, que en el momento de enfrentar una situación terminal no está preparada para elegir la mejor opción. OBJETIVO: Estudio piloto (n = 544) para conocer lo que la población abierta entiende acerca de términos utilizados al final de la vida en cuatro ciudades de la república mexicana. MÉTODO: Encuesta vía internet de 18 preguntas sobre los distintos términos. Se trató de un estudio descriptivo, transversal, con análisis estadístico. RESULTADOS: Se eligieron personas mayores de 18 años que no trabajaran en profesiones relacionadas con la salud. CONCLUSIONES: La mayoría de los términos del final de la vida no interesaron ni fueron entendidos por parte de la población. El término menos reconocido fue la obstinación terapéutica (62.8 %) y el más conocido, cuidados paliativos (91 %); se confunden los términos eutanasia y suicidio asistido (47.8 %). La edad y escolaridad resultaron de mayor influencia en los resultados, que las otras variables demográficas.

Encuesta en población abierta respecto a términos relacionados con decisiones al final de la vida / Open population survey regarding terms related to decisions at the end of life

Resumen Introducción: Conceptos relacionados con las decisiones que se toman al final de la vida, como eutanasia, cuidados paliativos, voluntad anticipada y obstinación terapéutica son poco comprendidos por la población en general, que en el momento de enfrentar una situación terminal no está preparada para elegir la mejor opción. Objetivo: Estudio piloto (n = 544) para conocer lo que la población abierta entiende acerca de términos utilizados al final de la vida en cuatro ciudades de la república mexicana. Método: Encuesta vía internet de 18 preguntas sobre los distintos términos. Se trató de un estudio descriptivo, transversal, con análisis estadístico. Resultados: Se eligieron personas mayores de 18 años que no trabajaran en profesiones relacionadas con la salud. Conclusiones: La mayoría de los términos del final de la vida no interesaron ni fueron entendidos por parte de la población. El término menos reconocido fue la obstinación terapéutica (62.8 %) y el más conocido, cuidados paliativos (91 %); se confunden los términos eutanasia y suicidio asistido (47.8 %). La edad y escolaridad resultaron de mayor influencia en los resultados, que las otras variables demográficas.

Abstract Introduction: Concepts related to end-of-life decisions, such as euthanasia, palliative care, advance directives and therapeutic obstinacy, are poorly understood by the general population, which, when facing a terminal situation, is not prepared to choose the best option. Objective: Pilot study (n = 544) to find out what the open population understands about terms used in end-of-life situations in four cities of the Mexican Republic. Method: Survey via Internet with 18 questions about different terms. It was a descriptive, cross-sectional study. Statistical analysis was carried out. Results: People older than 18 years who were not engaged in health-related professional activities were selected. Conclusions: Most terms related to end-of-life decisions were found not to be interesting to or understood by a part of the population. The least recognized term was therapeutic obstinacy (62.8%), and the most widely known, palliative care (91%); there was confusion between the terms euthanasia and assisted suicide (47.8%). Age and education level had more influence in the results, than other demographic variables.

The Effect of Blood-Derived Products on the Chondrogenic and Osteogenic Differentiation Potential of Adipose-Derived Mesenchymal Stem Cells Originated from Three Different Locations.

BACKGROUND: Adipose-derived mesenchymal stem cells (AD-MSCs) from fat tissue considered "surgical waste" during joint surgery may provide a potent source for regenerative medicine. Intra-articular, homologous fat tissue (Hoffa's fat pad, pouch fat) might possess a superior chondrogenic and osteogenic differentiation potential in comparison to extra-articular, nonhomologous fat. Blood products might further enhance this potential. METHODS: AD-MSCs were isolated from fat tissue of 3 donors from 3 locations each, during total knee replacement. Isolated cells were analyzed via flow cytometry. Cells were supplemented with blood products: two types of platelet-rich plasma (EPRP-PRP prepared in the presence of EDTA; CPRP-PRP prepared in the presence of citrate), hyperacute serum (hypACT), and standard fetal calf serum (FCS) as a positive control. The viability of the cells was determined by XTT assay, and the progress of differentiation was tested via histological staining and monitoring of specific gene expression. RESULTS: Blood products enhance ex vivo cell metabolism. Chondrogenesis is enhanced by EDTA-PRP and osteogenesis by citrate PRP, whereas hyperacute serum enhances both differentiations comparably. This finding was consistent in histological analysis as well as in gene expression. Lower blood product concentrations and shorter differentiation periods lead to superior histological results for chondrogenesis. Both PRP types had a different biological effect depending upon concentration, whereas hyperacute serum seemed to have a more consistent effect, independent of the used concentration. CONCLUSION: (i) Blood product preparation method, (ii) type of anticoagulant, (iii) differentiation time, and (iv) blood product concentration have a significant influence on stem cell viability and the differentiation potential, favouring no use of anticoagulation, shorter differentiation time, and lower blood product concentrations. Cell-free blood products like hyperacute serum may be considered as an alternative supplementation in regenerative medicine, especially for stem cell therapies.

Tuberculides tuberculosas en población adulta de la Región Metropolitana, Chile: serie de casos 2006-2010 / Tuberculids in the adult population of the Region Metropolitan, Chile: case series 2006-2010

Introducción: Las tuberculides tuberculosas (TLTB) se subdividen en verdaderas de etiología atribuible al Mycobacterium tuberculosis y facultativas causadas por múltiples condiciones, entre ellas la tuberculosis. En Chile representan el 75% de las tuberculosis cutáneas en la región metropolitana (RM). Objetivo: caracterizar las TLTB de la RM de acuerdo a epidemiología, clínica, estudio y manejo terapéutico. Material y método: Estudio descriptivo retrospectivo del total de TLTB diagnosticadas por biopsia en los servicios de anatomía patológica de 4 hospitales públicos de la RM y un hospital privado de la RM en el quinquenio 2006-2010. Resultados: 83 casos de TLTB, 59% aportados por el sistema público, 84% de los pacientes fueron mujeres, 18% fueron tuberculides verdaderas y 82% tuberculides facultativas. A pesar de ser el tratamiento antituberculoso la elección en las tuberculides verdaderas, sólo se indicó en el 65% de los casos y de estos, 45% realmente lo realizó. Sólo el 4,5% de las tuberculides facultativas de esta serie tuvieron indicación de tratamiento antituberculoso, realizándose en el 100% de los casos. Conclusión: Existe seguimiento insuficiente a través del tiempo en estos pacientes, dificultando dimensionar el éxito real de los tratamientos indicados. Se evidencia una falla en la coordinación al momento de derivar los pacientes al programa de control de la tuberculosis.

Introduction: Tuberculids are subdivided in true tuberculids, which are associated to mycobacterium tuberculosis, and facultative tuberculids which can be caused by several conditions, including tuberculosis. In Chile tuberculids represent 75% of cutaneous tuberculosis in the metropolitan region (MR). Objective: to characterize tuberculids according to epidemiology, clinical, study and therapeutic management. Methods: Descriptive study of the total tuberculids diagnosed by biopsy in the pathology services of 4 public hospitals of the MRI and a private hospital of the MRI in the five-year period 2006- 2010. Results: 83 cases of tuberculids, 59% where provided by the public system, 84% of the patients were women, 18% were true tuberculids and 82% facultative tuberculids. Despite being antitubercular therapy the first line treatment for true tuberculids, this treatment was prescribed in 65% of cases and only 45% of these were actually treated. Only 4.5% of the facultative tuberculids in this series had indication of antitubercular therapy, performed in 100% of cases. Conclusions: There is insufficient follow up in these patients, making it difficult to assess the real success of the treatment. Is evident the lack of coordination when referring patients to the tuberculosis control program.