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Yolk sac macrophages are the first to seed the developing heart, however we have no understanding of their roles in human heart development and function due to a lack of accessible tissue. Here, we bridge this gap by differentiating human embryonic stem cells (hESCs) into primitive LYVE1+ macrophages (hESC-macrophages) that stably engraft within contractile cardiac microtissues composed of hESC-cardiomyocytes and fibroblasts. Engraftment induces a human fetal cardiac macrophage gene program enriched in efferocytic pathways. Functionally, hESC-macrophages trigger cardiomyocyte sarcomeric protein maturation, enhance contractile force and improve relaxation kinetics. Mechanistically, hESC-macrophages engage in phosphatidylserine dependent ingestion of apoptotic cardiomyocyte cargo, which reduces microtissue stress, leading hESC-cardiomyocytes to more closely resemble early human fetal ventricular cardiomyocytes, both transcriptionally and metabolically. Inhibiting hESC-macrophage efferocytosis impairs sarcomeric protein maturation and reduces cardiac microtissue function. Taken together, macrophage-engineered human cardiac microtissues represent a considerably improved model for human heart development, and reveal a major beneficial role for human primitive macrophages in enhancing early cardiac tissue function.
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Nanoparticles used for drug delivery often require intravenous administration exposing them to fluid forces within the vasculature, yet the impact of blood flow on nanoparticle delivery remains incompletely understood. Here, we utilized transgenic zebrafish embryos to investigate the relationship between the accumulation of fluorescently labeled PEGylated liposomes and various hemodynamic factors (such as flow velocity, wall shear stress (WSS), and flow pattern) across a wide range of angiogenic blood vessels. We reconstructed 3D models of vascular structures from confocal images and used computational fluid dynamics to calculate local WSS, velocities, and define flow patterns. The spatial distribution of fluorescently labeled liposomes was subsequently mapped within the same 3D space and correlated with local hemodynamic parameters. Through the integration of computational fluid dynamics and in vivo experimentation, we show that liposomes accumulated in vessel regions with WSS between 0.1-0.8 Pa, displaying an inverse linear correlation (R2 > 0.85) between time-averaged wall shear stress and liposome localization in vivo. Interestingly, flow pattern did not appear to impact liposome accumulation. Collectively, our findings suggest the potential of stealth liposomes for passive targeting of low-flow vasculature, including capillaries and intricate angiogenic vasculature resembling that of tumor vessel networks.
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The wheel re-profiling is an important part of railway wheelset maintenance. Researchers and railway operators have been very concerned about how to minimize the loss of time during wheel re-profiling without decreasing safety. Avoiding wheelset disassembly means considerable time savings, while reducing wheel damage during operation. Underfloor wheel lathes are the most appropriate tool to achieve this double objective, and therefore the most used nowadays. Multi-cut tool lathes have the disadvantage of being extremely expensive. On the other hand, with single tool lathes, re-profiling is not smooth or safe enough when current convex profile support rollers are used. It is well known by the companies that during reprofiling the wheel suffers impacts/damaged. In this article, a methodology to optimize the profile of the support rollers used in underfloor single tool lathes for railway wheel re-profiling is proposed. This novel profile design will minimize damage and increase the safety of such lathes, since it proposes a greater smoothness in the process. Simulations of re-profiling process have been carried out by the finite element method showing that the designed roller profile reduces drastically the impact/damage during the operation. The impact generated between the re-profiling wheel and the rollers is avoided. Profile-optimized support rollers have been used in a real underfloor wheel lathe, showing good results.
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BACKGROUND: Human pluripotent stem cell (hPSC)-derived cardiomyocytes (hPSC-CMs) have tremendous promise for application in cardiac regeneration, but their translational potential is limited by an immature phenotype. We hypothesized that large-scale manufacturing of mature hPSC-CMs could be achieved through culture on polydimethylsiloxane (PDMS)-lined roller bottles and that the transplantation of these cells would mediate better structural and functional outcomes than with conventional immature hPSC-CM populations. METHODS: We comprehensively phenotyped hPSC-CMs after in vitro maturation for 20 and 40 days on either PDMS or standard tissue culture plastic substrates. All hPSC-CMs were generated from a transgenic hPSC line that stably expressed a voltage-sensitive fluorescent reporter to facilitate in vitro and in vivo electrophysiological studies, and cardiomyocyte populations were also analyzed in vitro by immunocytochemistry, ultrastructure and fluorescent calcium imaging, and bulk and single-cell transcriptomics. We next compared outcomes after the transplantation of these populations into a guinea pig model of myocardial infarction using end points including histology, optical mapping of graft- and host-derived action potentials, echocardiography, and telemetric electrocardiographic monitoring. RESULTS: We demonstrated the economic generation of >1×108 mature hPSC-CMs per PDMS-lined roller bottle. Compared with their counterparts generated on tissue culture plastic substrates, PDMS-matured hPSC-CMs exhibited increased cardiac gene expression and more mature structural and functional properties in vitro. More important, intracardiac grafts formed with PDMS-matured myocytes showed greatly enhanced structure and alignment, better host-graft electromechanical integration, less proarrhythmic behavior, and greater beneficial effects on contractile function. CONCLUSIONS: We describe practical methods for the scaled generation of mature hPSC-CMs and provide the first evidence that the transplantation of more mature cardiomyocytes yields better outcomes in vivo.
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Miocitos Cardíacos , Células Madre Pluripotentes , Animales , Diferenciación Celular , Línea Celular , Cobayas , Humanos , Miocitos Cardíacos/metabolismo , Plásticos/metabolismo , Células Madre Pluripotentes/metabolismoRESUMEN
Betaine is an osmolyte with the potential to increase volatile fatty acids (VFAs) production and hence improve intestinal health.The present study investigated how betaine affects portal and arterial concentrations and net portal absorption (NPA) of VFA in growing Iberian pigs. Eight 30â¯kg BW Iberian growing barrows with indwelling catheters in portal vein, ileal vein and carotid artery were randomly assigned to a control diet or a diet supplemented with 0.5% betaine. Para-aminohippuric acid was infused into the ileal vein as a marker to determine portal blood flow using the dilution method. Blood samples were simultaneously taken from the carotid artery and portal vein at -60, 60, 120, 180, 240, 300 and 360â¯min after feeding 1 200â¯g of the diet. The NPA of VFA (acetate, propionate, butyrate, valerate, isobutyrate and caproate) was determined by multiplying the porto-arterial plasma concentration differences by portal plasma flow. Betaine increased NPA of acetate (1.44 fold; Pâ¯<â¯0.001) and total VFA (0.55 fold; Pâ¯<â¯0.001) while decreased NPA of propionate (-0.38 fold; Pâ¯<â¯0.05) and valerate (-1.46 fold; Pâ¯<â¯0.05) compared with control pigs. Estimated heat production potentially derived from NPA of VFA accounted for 0.20-0.27 of metabolizable energy for maintenance. Acetate and propionate accounted for most of the total VFA estimated heat production (0.83-0.89). Regarding bacterial communities, betaine apparently did not change the DNA abundance of fecal total bacteria, Lactobacillus, Bifidobacterium, Enterobacteriaceae, Bacteroides and the Clostridium clusters I, IV and XIV. In conclusion, betaine increased portal appearance and NPA of VFA, contributing to cover maintenance energy requirements.
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Betaína , Ácidos Grasos Volátiles , Animales , Butiratos , Dieta , Propionatos , PorcinosRESUMEN
Human pluripotent stem cell derived cardiomyocytes (hPSC-CMs) represent an inexhaustible cell source for in vitro disease modeling, drug discovery and toxicity screening, and potential therapeutic applications. However, currently available differentiation protocols yield populations of hPSC-CMs with an immature phenotype similar to cardiomyocytes in the early fetal heart. In this review, we consider the developmental processes and signaling cues involved in normal human cardiac maturation, as well as how these insights might be applied to the specific maturation of hPSC-CMs. We summarize the state-of-the-art and relative merits of reported hPSC-CM maturation strategies including prolonged duration in culture, metabolic manipulation, treatment with soluble or substrate-based cues, and tissue engineering approaches. Finally, we review the evidence that hPSC-CMs mature after implantation in injured hearts as such in vivo remodeling will likely affect the safety and efficacy of a potential hPSC-based cardiac therapy.
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Miocitos Cardíacos/metabolismo , Células Madre Pluripotentes/metabolismo , Diferenciación Celular , HumanosRESUMEN
BACKGROUND AND OBJECTIVES: Diabetes is a significant risk factor for the development of cardiovascular disease, which is the main cause of death. The purpose of this study was to determine the level of glycaemic control in patients with type 2 diabetes without cardiovascular disease in Spain. The data used includes the most recent determination of glycosylated haemoglobin, as well as the pattern of antidiabetic treatment, the incidence of episodes of severe hypoglycaemia in the last 6 months, and the level of control of cardiovascular risk factors, and gender. PATIENTS AND METHODS: A national, multicentre, and cross-sectional epidemiological study in which 800 doctors associated with the GDPS network participated. RESULTS: Of the total of 1,059 patients, 57% male, with a mean age of 62.7 years in men vs. 65.2 in women (P<.001). The mean onset of diabetes was 9.4±7.5 years. The mean HbA1C was 7.0% in men vs. 7.1% in women (P=.039), with the control objective of <7% being observed in 47.2%. There were 65% patients on treatment with metformin, and 62.4% on DPP-4 inhibitors, and basal insulin: 14.2%. Incidence of severe hypoglycemias in the last 6 months was 1.9%. The women had worse glycaemic control, total cholesterol, LDL cholesterol, abdominal obesity, and glomerular filtration levels. CONCLUSIONS: The glycaemic control is worse in women even if adjusted for age and time of onset of diabetes (P=.043), and for the number of hypoglycaemic agents (P=.015). The level of control is also worse in women for dyslipidaemia, abdominal obesity, and glomerular filtration. A preventive strategy promoted from Primary care on healthy lifestyles and controlling all vascular risk factors is essential.
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Enfermedades Cardiovasculares , Glucemia , Estudios Transversales , Diabetes Mellitus Tipo 2 , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes , Masculino , Persona de Mediana Edad , EspañaRESUMEN
INTRODUCTION AND OBJECTIVES: With the implementation of the Strategy of Health Promotion and Prevention in Spain, the scenario reflected in previous studies of low control of cardiovascular risk factors (CVRF) in patients with type 2 diabetes (DM2) and cardiovascular disease (CVD) can be modified. This study intends to determine the level of blood glucose control and other CVRF in patients with DM2 and CVD currently seen in clinics in Spain, as well as the pattern of antidiabetic treatment, and differences according to gender. MATERIALS AND METHODS: An epidemiological, observational, cross-sectional, nationwide study was conducted in patients of both genders diagnosed with DM2 and established CVD. RESULTS: The study included 3,143 patients with a mean age 69.0±10 years. The mean HbA1c was 7.4±1.1% in females vs 7.3±1.2% in males (P<.05) and systolic blood pressure was 137±15.0mmHg in females vs 135.6±14.7mmHg in males (P<.05). The mean LDL-cholesterol was 101.5±38.1mg/dl in females vs 91.1±37.5mg/dl in males; P<.001) and the mean body mass index (30.7±5.4kg/m2 in females vs 29.6±4.5kg/m2 in males; P<.001). The most used treatments were metformin (68.1%) and/or DPP4 inhibitors (53.7%), with no differences between genders. CONCLUSIONS: The level of blood glucose control of DM2 patients with CVD in Spain can be improved. The treatment profile does not conform to the recommendations of clinical practice guidelines in general. The differences in the control of CVRF are worse in women for lipids and obesity.
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Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Control Glucémico , Hipoglucemiantes/administración & dosificación , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Estudios Transversales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Femenino , Hemoglobina Glucada/metabolismo , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Factores Sexuales , EspañaRESUMEN
Nanoparticles in the bloodstream are subjected to complex fluid forces as they move through the curves and branches of healthy or tumor vasculature. While nanoparticles are known to preferentially accumulate in angiogenic vessels, little is known about the flow conditions in these vessels and how these conditions may influence localization. Here, we report a methodology which combines confocal imaging of nanoparticle-injected transgenic zebrafish embryos, 3D modeling of the vasculature, particle mapping, and computational fluid dynamics, to quantitatively assess the effects of fluid forces on nanoparticle distribution in vivo. Six-fold lower accumulation was found in zebrafish arteries compared to the lower velocity veins. Nanoparticle localization varied inversely with shear stress. Highest accumulation was present in regions of disturbed flow found at branch points and curvatures in the vasculature. To further investigate cell-particle association under flow, human endothelial cells were exposed to nanoparticles under hemodynamic conditions typically found in human vessels. Physiological adaptations of endothelial cells to 20 hours of flow enhanced nanoparticle accumulation in regions of disturbed flow. Overall our results suggest that fluid shear stress magnitude, flow disturbances, and flow-induced changes in endothelial physiology modulate nanoparticle localization in angiogenic vessels.
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Endotelio Vascular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Nanopartículas , Estrés Mecánico , Animales , Animales Modificados Genéticamente , Vasos Sanguíneos , Embrión no Mamífero , Hemodinámica , Humanos , Pez CebraRESUMEN
BACKGROUND: Onset during old age has been reported in upto 10% of total cases of inflammatory bowel disease (IBD). AIM: To evaluate phenotypic characteristics and the use of therapeutic resources in patients with elderly onset IBD. METHODS: Case-control study including all those patients diagnosed with IBD over the age of 60 years since 2000 who were followed-up for >12 months, identified from the IBD databases. Elderly onset cases were compared with IBD patients aged 18 to 40 years at diagnosis, matched by year of diagnosis, gender and type of IBD (adult-onset). RESULTS: One thousand three hundred and seventy-four elderly onset and 1374 adult-onset cases were included (62% ulcerative colitis (UC), 38% Crohn's disease (CD)). Among UC patients, elderly onset cases had a lower proportion of extensive disease (33% vs 39%; P < 0.0001). In CD, elderly onset cases showed an increased rate of stenosing pattern (24% vs 13%; P < 0.0001) and exclusive colonic location (28% vs 16%; P < 0.0001), whereas penetrating pattern (12% vs 19%; P < 0.0001) was significantly less frequent. Regarding the use of therapeutic resources, there was a significantly lower use of corticosteroids (P < 0.0001), immunosuppressants (P < 0.0001) and anti-TNFs agents (P < 0.0001) in elderly onset cases. Regarding surgery, we found a significantly higher surgery rate among elderly onset UC cases (8.3% vs 5.1%; P < 0.009). Finally, elderly onset cases were characterised by a higher rate of hospitalisations (66% vs 49%; P < 0.0001) and neoplasms (14% vs 0.5%; P < 0.0001). CONCLUSIONS: Elderly onset IBD shows specific characteristics and they are managed differently, with a lower use of immunosuppressants and a higher rate of surgery in UC.
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Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Inflamatorias del Intestino/terapia , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Retrospectivos , España/epidemiología , Adulto JovenRESUMEN
The effect of surface PEGylation on nanoparticle transport through an extracellular matrix (ECM) is an important determinant for tumor targeting success. Fluorescent stealth liposomes (base lipid DOPC) were prepared incorporating different proportions of PEG-grafted lipids (2.5, 5 and 10% of the total lipid content) for a series of PEG molecular weights (1000, 2000 and 5000 Da). The ECM was modelled using a collagen matrix. The kinetics of PEGylated liposome adhesion to and transport in collagen matrices were tracked using fluorescence correlation spectroscopy (FCS) and confocal microscopy, respectively. Generalized least square regressions were used to determine the temporal correlations between PEG molecular weight, surface density and conformation, and the liposome transport in a collagen hydrogel over 15 hours. PEG conformation determined the interaction of liposomes with the collagen hydrogel and their transport behaviour. Interestingly, liposomes with mushroom PEG conformation accumulated on the interface of the collagen hydrogel, creating a dense liposomal front with short diffusion distances into the hydrogels. On the other hand, liposomes with dense brush PEG conformation interacted to a lesser extent with the collagen hydrogel and diffused to longer distances. In conclusion, a better understanding of PEG surface coating as a modifier of transport in a model ECM matrix has resulted. This knowledge will improve design of future liposomal drug carrier systems.
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Despite years of excellent individual studies, the impact of nanoparticle (NP) cytotoxicity studies remains limited by inconsistent data collection and analysis. It is often unclear how exposure conditions can be used to determine cytotoxicity quantitatively. Discrepancies due to using different measurement conditions, readouts and controls to characterize NP interactions with cells lead to further challenges. To examine which parameters are critical in NP cytotoxicity studies, we have chosen to examine two NP types (liposomes and quantum dots) at different concentrations incubated with two primary vascular endothelial cells, HUVEC and HMVEC-C for a standard time of 24 h. We paid close attention to the effects of positive controls and cell association on interpretation of cytotoxicity data. Various cellular responses (ATP content, oxidative stress, mitochondrial toxicity, and phospholipidosis) were measured in parallel. Interestingly, cell association data varied significantly with the different image analyses. However, cytotoxicity responses could all be correlated with exposure concentration. Cell type did have an effect on cytotoxicity reports. Most significantly, NP cytotoxicity results varied with the inclusion or exclusion of positive controls. In the absence of positive controls, one tends to emphasize small changes in cell responses to NPs.
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No disponible
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Humanos , Femenino , Adulto , Celulitis/diagnóstico , Celulitis/tratamiento farmacológico , Pasteurella multocida , Pasteurella multocida/aislamiento & purificación , Eritema Nudoso/complicaciones , Eritema Nudoso/diagnóstico , Eritema Nudoso/tratamiento farmacológico , Infecciones por Pasteurella/complicaciones , Infecciones por Pasteurella/tratamiento farmacológico , Mordeduras y Picaduras/complicaciones , Combinación Amoxicilina-Clavulanato de Potasio/uso terapéuticoRESUMEN
No disponible
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Humanos , Masculino , Persona de Mediana Edad , Fiebre Q/complicaciones , Coxiella burnetii/patogenicidad , Exantema/etiología , Diagnóstico DiferencialRESUMEN
OBJECTIVES: The aims of this study were to assess the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) drugs in patients with inflammatory bowel disease (IBD), to identify the factors associated with relapse, and to evaluate the overcome after retreatment with the same anti-TNF in those who relapsed. METHODS: This was a retrospective, observational, multicenter study. IBD patients who had been treated with anti-TNFs and in whom these drugs were discontinued after clinical remission was achieved were included. RESULTS: A total of 1,055 patients were included. The incidence rate of relapse was 19% and 17% per patient-year in Crohn's disease and ulcerative colitis patients, respectively. In both Crohn's disease and ulcerative colitis patients in deep remission, the incidence rate of relapse was 19% per patient-year. The treatment with adalimumab vs. infliximab (hazard ratio (HR)=1.29; 95% confidence interval (CI)=1.01-1.66), elective discontinuation of anti-TNFs (HR=1.90; 95% CI=1.07-3.37) or discontinuation because of adverse events (HR=2.33; 95% CI=1.27-2.02) vs. a top-down strategy, colonic localization (HR=1.51; 95% CI=1.13-2.02) vs. ileal, and stricturing behavior (HR=1.5; 95% CI=1.09-2.05) vs. inflammatory were associated with a higher risk of relapse in Crohn's disease patients, whereas treatment with immunomodulators after discontinuation (HR=0.67; 95% CI=0.51-0.87) and age (HR=0.98; 95% CI=0.97-0.99) were protective factors. None of the factors were predictive in ulcerative colitis patients. Retreatment of relapse with the same anti-TNF was effective (80% responded) and safe. CONCLUSIONS: The incidence rate of inflammatory bowel disease relapse after anti-TNF discontinuation is relevant. Some predictive factors of relapse after anti-TNF withdrawal have been identified. Retreatment with the same anti-TNF drug was effective and safe.