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Preclinical data have confirmed that human pluripotent stem cell-derived cardiomyocytes (PSC-CMs) can remuscularize the injured or diseased heart, with several clinical trials now in planning or recruitment stages. However, because ventricular arrhythmias represent a complication following engraftment of intramyocardially injected PSC-CMs, it is necessary to provide treatment strategies to control or prevent engraftment arrhythmias (EAs). Here, we show in a porcine model of myocardial infarction and PSC-CM transplantation that EAs are mechanistically linked to cellular heterogeneity in the input PSC-CM and resultant graft. Specifically, we identify atrial and pacemaker-like cardiomyocytes as culprit arrhythmogenic subpopulations. Two unique surface marker signatures, signal regulatory protein α (SIRPA)+CD90-CD200+ and SIRPA+CD90-CD200-, identify arrhythmogenic and non-arrhythmogenic cardiomyocytes, respectively. Our data suggest that modifications to current PSC-CM-production and/or PSC-CM-selection protocols could potentially prevent EAs. We further show that pharmacologic and interventional anti-arrhythmic strategies can control and potentially abolish these arrhythmias.
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Arritmias Cardíacas , Miocitos Cardíacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/trasplante , Animales , Arritmias Cardíacas/terapia , Humanos , Modelos Animales de Enfermedad , Infarto del Miocardio/terapia , Porcinos , Células Cultivadas , Diferenciación Celular , Células Madre Pluripotentes Inducidas/trasplante , Potenciales de Acción/fisiología , Potenciales de Acción/efectos de los fármacos , Fenotipo , Biomarcadores/metabolismo , Células Madre Pluripotentes/trasplante , Trasplante de Células Madre/métodos , Antiarrítmicos/uso terapéutico , Antiarrítmicos/farmacología , Frecuencia Cardíaca/fisiologíaRESUMEN
The development of small-diameter vascular grafts requires testing in large animal models before advancing to clinical trials. Vascular graft interposition implantation in sheep carotid arteries (CAs) is the most widely used model, but ovine CAs are prone to severe spasm following surgical manipulation, potentially impairing graft performance assessment. There is paucity in the literature on reducing sheep CA spasm using effective vasodilator therapeutic protocols. In this study, four healthy Merino cross White Suffolk wethers (1-2 years, 52.1 ± 0.8 kg) underwent CT angiography and CA graft surgery. CT angiography using iodinated contrast agent was performed with innominate artery access through the CA or ascending aortic arch access through the femoral artery. Sheep then underwent right CA sham surgery or left CA vascular graft implantation. A variety of vasodilators, including papaverine, sodium nitroprusside, verapamil, and their combination, were tested for preventing or treating CA spasms intraoperatively. Blood flow was reassessed immediately after CA surgery using CT angiography. The results showed that innominate artery access through the CA for CT angiography in sheep induced presurgical CA spasm with reduced arterial flow. Conversely, ascending aortic arch access through the femoral artery for CT angiography did not cause CA spasm and maintained arterial flow. During CA graft surgery, surgical trauma induced CA spasm, which was prevented by localized intra-arterial administration of vasodilators papaverine hydrochloride and verapamil before significant surgical manipulation.
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Arterias Carótidas , Angiografía por Tomografía Computarizada , Animales , Ovinos , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/efectos de los fármacos , Vasodilatadores/farmacología , Injerto Vascular/métodos , FemeninoRESUMEN
Immunohistochemistry (IHC) and immunofluorescence (IF) are crucial techniques for studying cardiac physiology and disease. The accuracy of these techniques is dependent on various aspects of sample preparation and processing. However, standardised protocols for sample preparation of tissues, particularly for fresh-frozen human left ventricle (LV) tissue, have yet to be established and could potentially lead to differences in staining and interpretation. Thus, this study aimed to optimise the reproducibility and quality of IF staining in fresh-frozen human LV tissue by systematically investigating crucial aspects of the sample preparation process. To achieve this, we subjected fresh-frozen human LV tissue to different fixation protocols, primary antibody incubation temperatures, antibody penetration reagents, and fluorescent probes. We found that neutral buffered formalin fixation reduced image artefacts and improved antibody specificity compared to both methanol and acetone fixation. Additionally, incubating primary antibodies at 37°C for 3 h improved fluorescence intensity compared to the commonly practised 4°C overnight incubation. Furthermore, we found that DeepLabel, an antibody penetration reagent, and smaller probes, such as fragmented antibodies and Affimers, improved the visualisation depth of cardiac structures. DeepLabel also improved antibody penetration in CUBIC cleared thick LV tissue fragments. Thus, our data underscores the importance of standardised protocols in IF staining and provides various means of improving staining quality. In addition to contributing to cardiac research by providing methodologies for IF, the findings and processes presented herein also establish a framework by which staining of other tissues may be optimised.
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Single-cell technology has allowed researchers to probe tissue complexity and dynamics at unprecedented depth in health and disease. However, the generation of high-dimensionality single-cell atlases and virtual three-dimensional tissues requires integrated reference maps that harmonize disparate experimental designs, analytical pipelines, and taxonomies. Here, we present a comprehensive single-cell transcriptome integration map of cardiac fibrosis, which underpins pathophysiology in most cardiovascular diseases. Our findings reveal similarity between cardiac fibroblast (CF) identities and dynamics in ischemic versus pressure overload models of cardiomyopathy. We also describe timelines for commitment of activated CFs to proliferation and myofibrogenesis, profibrotic and antifibrotic polarization of myofibroblasts and matrifibrocytes, and CF conservation across mouse and human healthy and diseased hearts. These insights have the potential to inform knowledge-based therapies.
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Fibroblastos , Fibrosis , Análisis de la Célula Individual , Transcriptoma , Animales , Análisis de la Célula Individual/métodos , Humanos , Fibroblastos/metabolismo , Ratones , Miocardio/metabolismo , Miocardio/patología , Miofibroblastos/metabolismo , Miofibroblastos/patología , Perfilación de la Expresión GénicaRESUMEN
Despite the high prevalence of heart failure in the western world, there are few effective treatments. Fibulin-3 is a protein involved in extracellular matrix (ECM) structural integrity, however its role in the heart is unknown. We have demonstrated, using single cell RNA-seq, that fibulin-3 was highly expressed in quiescent murine cardiac fibroblasts, with expression highest prior to injury and late post-infarct (from ~ day-28 to week-8). In humans, fibulin-3 was upregulated in left ventricular tissue and plasma of heart failure patients. Fibulin-3 knockout (Efemp1-/-) and wildtype mice were subjected to experimental myocardial infarction. Fibulin-3 deletion resulted in significantly higher rate of cardiac rupture days 3-6 post-infarct, indicating a weak and poorly formed scar, with severe ventricular remodelling in surviving mice at day-28 post-infarct. Fibulin-3 knockout mice demonstrated less collagen deposition at day-3 post-infarct, with abnormal collagen fibre-alignment. RNA-seq on day-3 infarct tissue revealed upregulation of ECM degradation and inflammatory genes, but downregulation of ECM assembly/structure/organisation genes in fibulin-3 knockout mice. GSEA pathway analysis showed enrichment of inflammatory pathways and a depletion of ECM organisation pathways. Fibulin-3 originates from cardiac fibroblasts, is upregulated in human heart failure, and is necessary for correct ECM organisation/structural integrity of fibrotic tissue to prevent cardiac rupture post-infarct.
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Proteínas de la Matriz Extracelular , Insuficiencia Cardíaca , Rotura Cardíaca , Infarto del Miocardio , Animales , Humanos , Ratones , Corazón , Insuficiencia Cardíaca/genética , Rotura Cardíaca/genética , Infarto del Miocardio/complicaciones , Infarto del Miocardio/genética , Proteínas de la Matriz Extracelular/genéticaRESUMEN
After myocardial infarction (MI), fibroblasts progress from proliferative to myofibroblast states, resulting in fibrosis. Platelet-derived growth factors (PDGFs) are reported to induce fibroblast proliferation, myofibroblast differentiation, and fibrosis. However, we have previously shown that PDGFs improve heart function post-MI without increasing fibrosis. We treated human cardiac fibroblasts with PDGF isoforms then performed RNA sequencing to show that PDGFs reduced cardiac fibroblasts myofibroblast differentiation and downregulated cell cycle pathways. Using mouse/pig MI models, we reveal that PDGF-AB infusion increases cell-cell interactions, reduces myofibroblast differentiation, does not affect proliferation, and accelerates scar formation. RNA sequencing of pig hearts after MI showed that PDGF-AB reduces inflammatory cytokines and alters both transcript variants and long noncoding RNA expression in cell cycle pathways. We propose that PDGF-AB could be used therapeutically to manipulate post-MI scar maturation with subsequent beneficial effects on cardiac function.
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BACKGROUND: Myocardial infarction (MI) is among the leading causes of death worldwide. Following MI, necrotic cardiomyocytes are replaced by a stiff collagen-rich scar. Compared to collagen, the extracellular matrix protein elastin has high elasticity and may have more favorable properties within the cardiac scar. We sought to improve post-MI healing by introducing tropoelastin, the soluble subunit of elastin, to alter scar mechanics early after MI. METHODS AND RESULTS: We developed an ultrasound-guided direct intramyocardial injection method to administer tropoelastin directly into the left ventricular anterior wall of rats subjected to induced MI. Experimental groups included shams and infarcted rats injected with either PBS vehicle control or tropoelastin. Compared to vehicle treated controls, echocardiography assessments showed tropoelastin significantly improved left ventricular ejection fraction (64.7±4.4% versus 46.0±3.1% control) and reduced left ventricular dyssynchrony (11.4±3.5 ms versus 31.1±5.8 ms control) 28 days post-MI. Additionally, tropoelastin reduced post-MI scar size (8.9±1.5% versus 20.9±2.7% control) and increased scar elastin (22±5.8% versus 6.2±1.5% control) as determined by histological assessments. RNA sequencing (RNAseq) analyses of rat infarcts showed that tropoelastin injection increased genes associated with elastic fiber formation 7 days post-MI and reduced genes associated with immune response 11 days post-MI. To show translational relevance, we performed immunohistochemical analyses on human ischemic heart disease cardiac samples and showed an increase in tropoelastin within fibrotic areas. Using RNA-seq we also demonstrated the tropoelastin gene ELN is upregulated in human ischemic heart disease and during human cardiac fibroblast-myofibroblast differentiation. Furthermore, we showed by immunocytochemistry that human cardiac fibroblast synthesize increased elastin in direct response to tropoelastin treatment. CONCLUSIONS: We demonstrate for the first time that purified human tropoelastin can significantly repair the infarcted heart in a rodent model of MI and that human cardiac fibroblast synthesize elastin. Since human cardiac fibroblasts are primarily responsible for post-MI scar synthesis, our findings suggest exciting future clinical translation options designed to therapeutically manipulate this synthesis.
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Infarto del Miocardio , Miocardio , Humanos , Ratas , Animales , Miocardio/metabolismo , Elastina/metabolismo , Tropoelastina/genética , Tropoelastina/metabolismo , Cicatriz , Volumen Sistólico , Función Ventricular Izquierda , Miocitos Cardíacos/metabolismo , Colágeno/metabolismo , Remodelación VentricularRESUMEN
BACKGROUND: Novel therapies that can limit or reverse damage caused by myocardial infarction (MI) could ease the increasing burden of heart failure. In this regard Platelet Derived Growth Factor (PDGF) has been previously shown to contribute to cardiac repair after MI. Here, we use a rodent model of MI and recombinant adeno-associated virus 9 (rAAV9)-mediated gene transfer to overexpress Pdgf-a in the injured heart and assess its therapeutic potential. METHODS AND RESULTS: Sprague Dawley rats underwent temporary occlusion of the left anterior descending coronary artery, followed immediately by systemic delivery of 1 × 10^11 vector genomes of either rAAV9 Pdgf-a or rAAV9 Empty vector (control). At day 28 post-MI echocardiography showed significantly improved left ventricular (LV) function (fractional shortening) after rAAV9 Pdgf-a (0.394 ± 0.019%) treatment vs control (0.304 ± 0.018%). Immunohistochemical analysis demonstrated significantly increased capillary and arteriolar density in the infarct border zone of rAAV9 Pdgf-a treated hearts together with a significant reduction in infarct scar size (rAAV9 Pdgf-a 6.09 ± 0.94% vs Empty 12.45 ± 0.92%). Western blot and qPCR analyses confirmed overexpression of PDGF-A and showed upregulation of smooth muscle alpha actin (Acta2), collagen type III alpha 1 (Col3a1) and lysyl oxidase (Lox) genes in rAAV9 Pdgf-a treated infarcts. CONCLUSION: Overexpression of Pdgf-a in the post-MI heart can modulate scar composition and improve LV function. Our study highlights the potential of rAAV gene transfer of Pdgf-a as a cardio-reparative therapy.
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Cicatriz , Infarto del Miocardio , Animales , Modelos Animales de Enfermedad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/genética , Infarto del Miocardio/terapia , Miocardio/patología , Factor de Crecimiento Derivado de Plaquetas/genética , Ratas , Ratas Sprague-Dawley , Función Ventricular Izquierda , Remodelación VentricularRESUMEN
PURPOSE: Despite modern reperfusion and pharmacologic therapies, myocardial infarction (MI) remains a leading cause of morbidity and mortality worldwide. Therefore, the development of further therapeutics affecting post-MI recovery poses significant benefits. This review focuses on the post-MI immune response and immunomodulatory therapeutics that could improve the wound-healing response. METHODS: This narrative review used OVID versions of MEDLINE and EMBASE searching for clinical therapeutics targeting the immune system during MI. Preclinical models and clinical trials were included. Additional studies were sourced from the reference lists of relevant articles and other personal files. FINDINGS: After MI, cardiomyocytes are starved of oxygen and undergo cell death via coagulative necrosis. This process activates the immune system and a multifaceted wound-healing response, comprising a number of complex and overlapping phases. Overactivation or persistence of one or more of these phases can have potentially lethal implications. This review describes the immune response post-MI and any adverse events that can occur during these different phases. Second, we describe immunomodulatory therapies that attempt to target these immune cell aberrations by mitigating or diminishing their effects on the wound-healing response. Also discussed are adult stem/progenitor cell therapies, exosomes, and regulatory T cells, and their immunomodulatory effects in the post-MI setting. IMPLICATIONS: An updated understanding into the importance of various inflammatory cell phenotypes, coupled with new technologies, may hold promise for a new era of immunomodulatory therapeutics. The implications of such therapies could dramatically improve patients' quality of life post-MI and reduce the incidence of progressive heart failure.
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Infarto del Miocardio/terapia , Trasplante de Células Madre/métodos , Cicatrización de Heridas/inmunología , Animales , Muerte Celular , Exosomas/metabolismo , Humanos , Inmunidad , Calidad de VidaRESUMEN
Therapies that target scar formation after myocardial infarction (MI) could prevent ensuing heart failure or death from ventricular arrhythmias. We have previously shown that recombinant human platelet-derived growth factor-AB (rhPDGF-AB) improves cardiac function in a rodent model of MI. To progress clinical translation, we evaluated rhPDGF-AB treatment in a clinically relevant porcine model of myocardial ischemia-reperfusion. Thirty-six pigs were randomized to sham procedure or balloon occlusion of the proximal left anterior descending coronary artery with 7-day intravenous infusion of rhPDGF-AB or vehicle. One month after MI, rhPDGF-AB improved survival by 40% compared with vehicle, and cardiac magnetic resonance imaging showed left ventricular (LV) ejection fraction improved by 11.5%, driven by reduced LV end-systolic volumes. Pressure volume loop analyses revealed improved myocardial contractility and energetics after rhPDGF-AB treatment with minimal effect on ventricular compliance. rhPDGF-AB enhanced angiogenesis and increased scar anisotropy (high fiber alignment) without affecting overall scar size or stiffness. rhPDGF-AB reduced inducible ventricular tachycardia by decreasing heterogeneity of the ventricular scar that provides a substrate for reentrant circuits. In summary, we demonstrated that rhPDGF-AB promotes post-MI cardiac wound repair by altering the mechanics of the infarct scar, resulting in robust cardiac functional improvement, decreased ventricular arrhythmias, and improved survival. Our findings suggest a strong translational potential for rhPDGF-AB as an adjunct to current MI treatment and possibly to modulate scar in other organs.
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Cicatriz/patología , Infarto del Miocardio/patología , Factor de Crecimiento Derivado de Plaquetas/farmacología , Animales , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/patología , Arritmias Cardíacas/fisiopatología , Arteriolas/efectos de los fármacos , Arteriolas/patología , Arteriolas/fisiopatología , Cicatriz/complicaciones , Cicatriz/tratamiento farmacológico , Cicatriz/fisiopatología , Colágeno/metabolismo , Fibrosis , Pruebas de Función Cardíaca/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/fisiopatología , Humanos , Contracción Miocárdica/efectos de los fármacos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Neovascularización Fisiológica/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/uso terapéutico , Proteínas Recombinantes/farmacología , Análisis de Supervivencia , Porcinos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Breast cancers are highly heterogeneous and their metastatic potential and response to therapeutic drugs is difficult to predict. A tool that could accurately gauge tumour invasiveness and drug response would provide a valuable addition to the oncologist's arsenal. We have developed a 3-dimensional (3D) culture model that recapitulates the stromal environment of breast cancers by generating anisotropic (directional) collagen scaffolds seeded with adipocytes and culturing tumour fragments therein. Analysis of tumour cell invasion in the presence of various therapeutic drugs, by immunofluorescence microscopy coupled with an optical clearing technique, demonstrated the utility of this approach in determining both the rate and capacity of tumour cells to migrate through the stroma while shedding light also on the mode of migration. Furthermore, the response of different murine mammary tumour types to chemotherapeutic drugs could be readily quantified.
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Adipocitos/citología , Movimiento Celular/fisiología , Colágeno/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Células 3T3-L1 , Animales , Femenino , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Microscopía FluorescenteRESUMEN
Adipocytes are one of the major stromal cell components of the human breast. These cells play a key role in the development of the gland and are implicated in breast tumorigenesis. Frequently, directional stromal collagen I fibers are found surrounding aggressive breast tumors. These fibers enhance breast cancer cell migration and are associated with poor patient prognosis. We sought to recapitulate these stromal components in vitro to provide a three-dimensional (3D) model comprising human adipose tissue and anisotropic collagen fibers. We developed a human mesenchymal stem cell (hMSC) cell line capable of undergoing differentiation into mature adipocytes by immortalizing hMSCs, isolated from breast reduction mammoplasties, through retroviral transduction. These immortalized hMSCs were seeded in engineered collagen I scaffolds with directional internal architecture, and adipogenesis was chemically induced, resulting in human adipose tissue being synthesized in vitro in an architectural structure associated with breast tumorigenesis. Subsequently, fluorescently labeled cells from an established breast cancer cell line were seeded into this model, cocultured for 7 days and imaged using multiphoton microscopy. Enhanced breast cancer cell migration was observed in the adipose-containing model over empty scaffold controls, demonstrating an adipocyte-mediated influence on breast cancer cell migration. Thus, this 3D in vitro model recapitulates the migratory effects of adipocytes observed on breast cancer cells and suggests that it could have utility with fresh breast tumor biopsies as an assay for cancer therapeutic efficacy in personalized medicine strategies.
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Tejido Adiposo/metabolismo , Neoplasias de la Mama/metabolismo , Movimiento Celular , Colágeno Tipo I/química , Modelos Biológicos , Ingeniería de Tejidos , Andamios del Tejido/química , Adipocitos/metabolismo , Adipocitos/patología , Tejido Adiposo/patología , Neoplasias de la Mama/patología , Línea Celular Transformada , Femenino , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Células Tumorales CultivadasRESUMEN
BACKGROUND: The recommendation for enteral iodide intake for preterm infants is 30 to 40 µg/kg per day and 1 µg/kg per day for parenteral intake. Preterm infants are vulnerable to iodide insufficiency and thyroid dysfunction. The hypothesis tested whether, compared with placebo, iodide supplementation of preterm infants improves neurodevelopment. METHODS: A randomized controlled trial of iodide supplementation versus placebo in infants <31 weeks' gestation. Trial solutions (sodium iodide or sodium chloride; dose 30 µg/kg per day) were given within 42 hours of birth to the equivalent of 34 weeks' gestation. The only exclusion criterion was maternal iodide exposure during pregnancy or delivery. Whole blood levels of thyroxine, thyrotropin, and thyroid-binding globulin were measured on 4 specific postnatal days. The primary outcome was neurodevelopmental status at 2 years of age, measured by using the Bayley Scales of Infant Development-III. The primary analyses are by intention-to-treat, and data are presented also for survivors. RESULTS: One thousand two hundred seventy-three infants (637 intervention, 636 placebo) were recruited from 21 UK neonatal units. One hundred thirty-one infants died, and neurodevelopmental assessments were undertaken in 498 iodide and 499 placebo-supplemented infants. There were no significant differences between the intervention and placebo groups in the primary outcome: mean difference cognitive score, -0.34, 95% confidence interval (CI) -2.57 to 1.89; motor composite score, 0.21, 95% CI -2.23 to 2.65; and language composite score, -0.05, 95% CI -2.48 to 2.39. There was evidence of weak interaction between iodide supplementation and hypothyroxinemic status in the language composite score and 1 subtest score. CONCLUSIONS: Overall iodide supplementation provided no benefit to neurodevelopment measured at 2 years of age.
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Encéfalo/crecimiento & desarrollo , Desarrollo Infantil/efectos de los fármacos , Recien Nacido Prematuro/fisiología , Yoduros/administración & dosificación , Nutrición Parenteral , Preescolar , Estudios de Seguimiento , Humanos , Lactante , Yoduros/efectos adversos , Nutrición Parenteral/efectos adversos , Tirotropina/sangre , Tiroxina/sangre , Globulina de Unión a Tiroxina/metabolismo , Resultado del TratamientoRESUMEN
Cancer is characterized by cell heterogeneity and the development of 3D in vitro assays that can distinguish more invasive or migratory phenotypes could enhance diagnosis or drug discovery. 3D collagen scaffolds have been used to develop analogues of complex tissues in vitro and are suited to routine biochemical and immunological assays. We sought to increase 3D model tractability and modulate the migration rate of seeded cells using an ice-templating technique to create either directional/anisotropic or non-directional/isotropic porous architectures within cross-linked collagen scaffolds. Anisotropic scaffolds supported the enhanced migration of an invasive breast cancer cell line MDA-MB-231 with an altered spatial distribution of proliferative cells in contrast to invasive MDA-MB-468 and non-invasive MCF-7 cells lines. In addition, MDA-MB-468 showed increased migration upon epithelial-to-mesenchymal transition (EMT) in anisotropic scaffolds. The provision of controlled architecture in this system may act both to increase assay robustness and as a tuneable parameter to capture detection of a migrated population within a set time, with consequences for primary tumour migration analysis. The separation of invasive clones from a cancer biomass with in vitro platforms could enhance drug development and diagnosis testing by contributing assay metrics including migration rate, as well as modelling cell-cell and cell-matrix interaction in a system compatible with routine histopathological testing.
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Neoplasias de la Mama/patología , Neoplasias de la Mama/fisiopatología , Movimiento Celular , Colágeno/química , Impresión Tridimensional , Análisis de Matrices Tisulares/instrumentación , Andamios del Tejido , Materiales Biomiméticos/síntesis química , Adhesión Celular , Línea Celular Tumoral , Diseño de Equipo , Matriz Extracelular/química , Humanos , Células MCF-7 , Ingeniería de Tejidos/instrumentaciónRESUMEN
BACKGROUND: Norepinephrine (NE) and epinephrine (EPI) levels are higher in cord arterial blood relative to venous blood, consistent with active mechanisms of placental-maternal clearance. There are no contemporary studies of cord arteriovenous blood levels of sulfated and non-sulfated catechols. AIM: To assess the arteriovenous differences in cord blood levels of dopamine (DA), the sulfated catecholamines and their sulfated and non-sulfated metabolites. To correlate levels of oxygen, H+/CO2, and glucose with cord catecholamine levels. METHODS: Fifty-seven term infants, delivered by elective cesarean section, were recruited. Cord arterial and venous blood was sampled; levels of glucose, lactate, blood gases, six catechols and their sulfated conjugates were measured. RESULTS: With one exception (DOPA sulfate), mean cord arterial levels of sulfated and non-sulfated catechols were significantly higher than venous levels. Arterial lactate and glucose levels were independently associated with NE levels, but only lactate was associated with levels of EPI and DA. CONCLUSION: This study establishes that in vivo metabolic parameters of hypoxia, respiratory and metabolic acidosis are associated with catecholamine levels, a key relationship for perinatal adaptation and homeostasis, and findings that are consistent with in vitro studies of the regulators of catecholamine secretion.
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Glucemia/metabolismo , Catecolaminas/sangre , Sangre Fetal/metabolismo , Ácido Láctico/sangre , Arterias , Análisis de los Gases de la Sangre , Cesárea , Femenino , Humanos , Recién Nacido , Masculino , Análisis de Regresión , VenasRESUMEN
AIM: To assess factors contributing to cord venous glucose homeostasis in term infants delivered by elective cesarean section. METHODS: Observational study of women-infant pairs at delivery. Biochemical and clinical data were collected about factors which might affect the levels of glucose, lactate, norepinephrine, epinephrine, cortisol, human growth hormone, glucagon, and insulin. RESULTS: In the context of this data-set, three models explained a substantial amount regarding the variation: 79% of the variation in cord glucose levels is explained by levels of maternal glucose, cord venous pH, and cord lactate; 77% of the variation of cord lactate is explained by levels of cord venous pH, valine, maternal lactate and glucose, and cord norepinephrine; and 71% of the variation in cord norepinephrine is explained by levels of cord venous pO2, maternal lactate, cord insulin, cord GABA (gamma-aminobutyric acid), cord lactate, cord epinephrine, cord norepinephrine sulfate, and cord valine. CONCLUSIONS: Term infants delivered by cesarean section are relatively hyperinsulinemic (insulin:glucose ratio of 2.4) and glucose levels are strongly associated with maternal glucose levels, cord pO2, and lactate levels. There were no associations with levels of cord glucose and levels of cortisol, epinephrine and lactate, which have been shown to be important contributors to postnatal glucose homeostasis in some infant groups.
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Glucemia/metabolismo , Cesárea , Sangre Fetal/metabolismo , Homeostasis , Embarazo/sangre , Adulto , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Recién Nacido , MasculinoRESUMEN
Breast cancer is a complex disease with many distinct subtypes being recognized on the basis of histological features and molecular signatures. It is difficult to predict how cancers will respond to therapy, which results in many women receiving unnecessary or inappropriate treatment. Advances in materials science and tissue engineering are leading the development of complex in vitro 3D breast tissue models that will increase our understanding of normal development and tumorigenic mechanisms. Ultimately, platforms that support primary tissue culture could readily be adapted to form high-throughput drug screening tools for personalized medicine. This review will summarize the control of mammary gland phenotype within in vitro 3D environments, in the context of a detailed analysis of mammary gland development and stem and progenitor cell controlled tumorigenesis.
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Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Glándulas Mamarias Animales/patología , Glándulas Mamarias Humanas/patología , Animales , Transformación Celular Neoplásica/patología , Femenino , Humanos , Técnicas In Vitro/métodos , Modelos Biológicos , Ingeniería de Tejidos/métodosRESUMEN
This paper summarises the study protocol for the randomised controlled trial of iodine supplementation in preterm infants. Iodine is essential for the synthesis of thyroxine, and thyroxine is essential for normal brain development in utero and for the first 2-3 years of life. The recommended iodine intake in parenteral nutrition regimens is 1 µg/kg/day and commercially available parenteral solutions for infants reflect these recommendations. In the absence of other iodine sources, infants are vulnerable to negative iodine balance and insufficiency. As many preterm infants are fed parenterally for prolonged periods with solutions which have been shown to be iodine-deficient, the I2S2 Trial was designed to establish whether iodine supplementation of preterm infants benefits neurodevelopment.
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Desarrollo Infantil , Suplementos Dietéticos , Recien Nacido Extremadamente Prematuro , Sistema Nervioso/efectos de los fármacos , Nutrición Parenteral , Proyectos de Investigación , Yoduro de Sodio/uso terapéutico , Factores de Edad , Protocolos Clínicos , Suplementos Dietéticos/efectos adversos , Edad Gestacional , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Sistema Nervioso/crecimiento & desarrollo , Estado Nutricional , Ingesta Diaria Recomendada , Yoduro de Sodio/efectos adversos , Factores de Tiempo , Resultado del TratamientoRESUMEN
CONTEXT: Relatively little is known in euthyroid populations about the changes in maternal thyroid hormones during pregnancy, the nature of the relationship to cord thyroid hormone levels, and subsequent infant neurodevelopment. OBJECTIVES: The aim of the study was to describe the relationship between maternal and cord thyroid hormone parameters and to describe their associations with neurodevelopment at 5.5 years. DESIGN: We conducted a follow-up of women and their children born at or over 37 weeks' gestation. MAIN OUTCOMES: We measured maternal levels of TSH, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), T(4), and free T(4) (FT(4)) at 10 and 34 weeks and at delivery, and cord levels of T(4), FT(4), TPOAb, and TgAb. The association of cord thyroid hormone parameters with McCarthy scale scores adjusted for the major confounders of neurodevelopment. RESULTS: Fifteen percent of the women were TPOAb-positive, and 12% were TgAb-positive; the proportion of women with mildly elevated TSH levels increased during pregnancy with the maximum (14%) at delivery. Lower perceptual performance and motor scores were found with TgAb-positive women and lower perceptual performance scores with TgAb-positive cord levels; otherwise, unadjusted maternal levels of TPOAb, TgAb, and TSH and unadjusted cord levels of FT(4), TPOAb, and TgAb were not associated with neurodevelopment at 5.5 years. Low cord T(4) levels were associated with significant increments in four McCarthy scales: General Cognitive Index, Verbal, Quantitative, and Memory scales-increments that persisted after adjustment at 11.4, 7.8, 7.6, and 7.8 points, respectively. CONCLUSIONS: Lower levels of cord T(4) were associated with increments in the McCarthy scales in the domains that tested cognitive and verbal abilities at 5.5 years.