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1.
Osteoarthritis Cartilage ; 31(3): 386-396, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36367486

RESUMEN

OBJECTIVE: To develop evidence-informed recommendations to support the delivery of best practice therapeutic exercise for people with knee and/or hip osteoarthritis (OA). DESIGN: A multi-stage, evidence-informed, international multi-disciplinary consensus process that included: 1) a narrative literature review to synthesise existing evidence; 2) generation of evidence-informed proposition statements about delivery of exercise for people with knee and/or hip OA by an international multi-disciplinary expert panel, with statements refined and analysed thematically; 3) an e-Delphi survey with the expert panel to gain consensus on the most important statements; 4) a final round of statement refinement and thematic analysis to group remaining statements into domains. RESULTS: The expert panel included 318 members (academics, health care professionals and exercise providers, patient representatives) from 43 countries. Final recommendations comprised 54 specific proposition statements across 11 broad domains: 1) use an evidence-based approach; 2) consider exercise in the context of living with OA and pain; 3) undertake a comprehensive baseline assessment with follow-up; 4) set goals; 5) consider the type of exercise; 6) consider the dose of exercise; 7) modify and progress exercise; 8) individualise exercise; 9) optimise the delivery of exercise; 10) focus on exercise adherence; and 11) provide education about OA and the role of exercise. CONCLUSION: The breadth of issues identified as important by the international diverse expert panel highlights that delivering therapeutic exercise for OA is multi-dimensional and complex.


Asunto(s)
Osteoartritis de la Cadera , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Cadera/terapia , Osteoartritis de la Rodilla/terapia , Terapia por Ejercicio/métodos , Ejercicio Físico , Medicina Basada en la Evidencia , Técnica Delphi
2.
Am J Physiol Heart Circ Physiol ; 318(2): H252-H263, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31809211

RESUMEN

Fetal growth restriction (FGR), where a fetus fails to reach its genetic growth potential, affects up to 8% of pregnancies and is a major risk factor for stillbirth and adulthood morbidity. There are currently no treatments for FGR, but candidate therapies include the phosphodiesterase-5 inhibitor sildenafil citrate (SC). Randomized clinical trials in women demonstrated no effect of SC on fetal growth in cases of severe early onset FGR; however, long-term health outcomes on the offspring are unknown. This study aimed to assess the effect of antenatal SC treatment on metabolic and cardiovascular health in offspring by assessing postnatal weight gain, glucose tolerance, systolic blood pressure, and resistance artery function in a mouse model of FGR, the placental-specific insulin-like growth factor 2 (PO) knockout mouse. SC was administered subcutaneously (10 mg/kg) daily from embryonic day (E)12.5. Antenatal SC treatment did not alter fetal weight or viability but increased postnatal weight gain in wild-type (WT) female offspring (P < 0.05) and reduced glucose sensitivity in both WT (P < 0.01) and P0 (P < 0.05) female offspring compared with controls. Antenatal SC treatment increased systolic blood pressure in both male (WT vs. WT-SC: 117 ± 2 vs. 140 ± 3 mmHg, P < 0.0001; P0 vs. P0-SC: 113 ± 3 vs. 140 ± 4 mmHg, P < 0.0001; means ± SE) and female (WT vs. WT-SC: 121 ± 2 vs. 140 ± 2 mmHg, P < 0.0001; P0 vs. P0-SC: 117 ± 2 vs. 144 ± 4 mmHg, P < 0.0001) offspring at 8 and 13 wk of age. Increased systolic blood pressure was not attributed to altered mesenteric artery function. In utero exposure to SC may result in metabolic dysfunction and elevated blood pressure in later life.NEW & NOTEWORTHY Sildenafil citrate (SC) is currently used to treat fetal growth restriction (FGR). We demonstrate that SC is ineffective at treating FGR, and leads to a substantial increase systolic blood pressure and alterations in glucose homeostasis in offspring. We therefore urge caution and suggest that further studies are required to assess the safety and efficacy of SC in utero, in addition to the implications on long-term health.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Retardo del Crecimiento Fetal/tratamiento farmacológico , Factor II del Crecimiento Similar a la Insulina/genética , Citrato de Sildenafil/uso terapéutico , Vasodilatadores/uso terapéutico , Animales , Peso al Nacer , Femenino , Retardo del Crecimiento Fetal/genética , Prueba de Tolerancia a la Glucosa , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Embarazo , Efectos Tardíos de la Exposición Prenatal , Circulación Esplácnica/efectos de los fármacos , Resistencia Vascular/efectos de los fármacos , Aumento de Peso/efectos de los fármacos
3.
Matern Child Health J ; 21(3): 421-431, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28093689

RESUMEN

Introduction Low-income populations have elevated exposure to early life risk factors for obesity, but are understudied in longitudinal research. Our objective was to assess the utility of a cohort derived from electronic health record data from safety net clinics for investigation of obesity emerging in early life. Methods We examined data from the PCORNet ADVANCE Clinical Data Research Network, a national network of Federally-Qualified Health Centers serving >1.7 million safety net patients across the US. This cohort includes patients who, in 2012-2014, had ≥1 valid body mass index measure when they were 0-5 years of age. We characterized the cohort with respect to factors required for early life obesity research in vulnerable subgroups: sociodemographic diversity, weight status based on World Health Organization (<2 years) or Centers for Disease Control (≥2 years) growth curves, and data longitudinality. Results The cohort includes 216,473 children and is racially/ethnically diverse (e.g., 17.9% Black, 45.4% Hispanic). A majority (56.9%) had family incomes below the Federal Poverty Level (FPL); 32% were <50% of FPL. Among children <2 years, 7.6 and 5.3% had high and low weight-for-length, respectively. Among children 2-5 years, 15.0, 12.7 and 2.4% were overweight, obese, and severely obese, respectively; 5.3% were underweight. In the study period, 79.2% of children had ≥2 BMI measures. Among 4-5 year olds, 21.9% had >1 BMI measure when they were <2 years. Discussion The ADVANCE Early Life cohort offers unique opportunities to investigate early life determinants of obesity in the understudied population of low income and minority children.


Asunto(s)
Bases de Datos como Asunto , Obesidad Infantil/epidemiología , Pobreza/estadística & datos numéricos , Índice de Masa Corporal , Niño , Preescolar , Estudios de Cohortes , Registros Electrónicos de Salud/organización & administración , Etnicidad/estadística & datos numéricos , Femenino , Humanos , Lactante , Masculino , Obesidad Infantil/economía , Obesidad Infantil/etiología , Factores de Riesgo , Clase Social , Estados Unidos/epidemiología
6.
Nurs Stand ; 27(21): 35-41, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23427684

RESUMEN

AIM: To determine healthcare professionals' knowledge of the calorie content of foods and the relationship to weight maintenance. METHOD: A cross-sectional questionnaire was used to survey 179 clinical staff, non-clinical staff and life coaches working in health care. RESULTS: The response rate is 81%. The majority of respondents identified the weight loss requirements necessary to achieve marked health benefits in obese patients. Estimation of calorie and salt contents of specified foods was generally inaccurate. The majority of healthcare professionals did not know the amount of exercise required to burn off the calories of commonly consumed foods. CONCLUSION: Support and education are required for healthcare professionals to manage the challenges associated with obesity.


Asunto(s)
Ingestión de Energía , Personal de Salud/psicología , Estudios Transversales , Ejercicio Físico , Humanos , Valor Nutritivo , Encuestas y Cuestionarios , Reino Unido
7.
Int J Obes (Lond) ; 36(8): 1040-6, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22124449

RESUMEN

BACKGROUND: Pups of normally nourished dams that are cross-fostered after birth to dams fed a low-protein (8% by weight) diet (postnatal low protein (PLP)) grow slower during the suckling period and remain small and lean throughout adulthood. At weaning, they have increased expression in the arcuate nucleus (ARC) of the hypothalamus of the orexigenic neuropeptide Y (NPY) and decreased expression of pro-opiomelanocortin, the precursor of anorexigenic melanocortins. OBJECTIVES AND METHODS: We investigated, using third ventricle administration, whether 3-month-old male PLP rats display altered sensitivity to leptin with respect to food intake, NPY and the melanocortin 3/4-receptor agonist MTII, and using in situ hybridization or laser capture microdissection of the ARC followed by RT-PCR, whether the differences observed were associated with changes in the hypothalamic expression of NPY or the leptin receptor, NPY receptors and melanocortin receptors. RESULTS: PLP rats were smaller and had reduced percentage body fat content and plasma leptin concentration compared with control rats. Leptin (5 µg) reduced food intake over 0-48 h more in PLP than control rats (P<0.05). Submaximal doses of NPY increased the food intake less in PLP rats than in controls, whereas submaximal doses of MTII reduced the food intake more in PLP rats. Maximal responses did not differ between PLP and control rats. Leptin and melanocortin-3 receptor (MC3R) expression were increased in both ARC and ventromedial hypothalamic nuclei in PLP animals compared with the controls. MC4R, NPY Y1R, Y5R and NPY expression were unchanged. CONCLUSION: Postnatal undernourishment results in food intake in adult rats being more sensitive to reduction by leptin and melanocortins, and less sensitive to stimulation by NPY. We propose that this contributes to increased leptin sensitivity and resistance to obesity. Increased expression of ObRb and MC3R may partly explain these findings but other downstream mechanisms must also be involved.


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Núcleo Arqueado del Hipotálamo/patología , Leptina/metabolismo , Neuropéptido Y/metabolismo , Obesidad/genética , Receptor de Melanocortina Tipo 3/metabolismo , Delgadez/genética , Animales , Núcleo Arqueado del Hipotálamo/fisiología , Peso Corporal/genética , Susceptibilidad a Enfermedades , Ingestión de Alimentos , Regulación de la Expresión Génica , Leptina/farmacología , Masculino , Neuropéptido Y/farmacología , Obesidad/metabolismo , Ratas , Ratas Wistar , Delgadez/metabolismo , Factores de Tiempo , Aumento de Peso/genética
8.
Physiotherapy ; 113: 199-208, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34656297

RESUMEN

OBJECTIVE: First Contact Physiotherapy (FCP) is a primary care model where expert musculoskeletal (MSK) physiotherapists undertake the first patient consultation, to enhance MSK-patient care and free-up GP capacity. The authors report the quantitative findings from the FCP National Evaluation (Phase 3) which evaluated the FCP model against success criteria. DESIGN AND SETTING: A mixed-methods 24-month service evaluation involving 40 FCP sites and 240 FCPs across England. METHODS: An online platform collected patient-reported experience and outcomes following the FCP consultation and at 1, 2 and 3-months follow-up. These included the Keele STarT MSK Tool, pain intensity (0-10 NRS scale), Musculoskeletal Health Questionnaire (MSK-HQ, range 0-56), and Friends-and-Family Test. RESULTS: Over 13 months, 2825 patients were invited by email and 24% (n=680) completed their initial questionnaire. Their mean age was 56.2 (SD 14.9), 61% were female, ethnicity was 97% white, mean pain intensity was 6.1 (SD 2.13) and mean MSK-HQ score was 33.8 (SD 9.5). At 3-months follow-up (n=370) there was a 2.8 (CI 2.5 to 3.1) mean pain intensity reduction from baseline, a mean 7.1 (6.0 to 8.2) score improvement in MSK-HQ and 64% reporting overall improvement (much better/better) since seeing the FCP. One of the six success criteria was not met; 29% of those in employment reported receiving specific work advice from the FCP (target ≥75%). CONCLUSION: Ahead of the planned scale-up of the FCP primary care model across the UK, this evaluation provides useful data on patients who access this service, their short-term clinical outcomes and whether key success criteria are being met.


Asunto(s)
Fisioterapeutas , Modalidades de Fisioterapia , Femenino , Humanos , Persona de Mediana Edad , Atención Primaria de Salud , Derivación y Consulta , Encuestas y Cuestionarios
9.
Infect Prev Pract ; 2(2): 100047, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34368697

RESUMEN

BACKGROUND: Invasive candidiasis (IC) is the most common invasive fungal disease in patients admitted to critical care and is associated with high mortality rates. Diagnosis can be delayed by the poor sensitivity of culture-based methods, leading to unnecessary use of empirical antifungal therapy (EAFT). The fungal biomarker (1-3)-ß-d-glucan (BDG) has been shown to aid in the diagnosis of IC in critical care and has been incorporated into antifungal stewardship (AFS) programmes. AIM: To describe our experience using a diagnostics-driven AFS programme incorporating the fungal biomarker BDG, analyse its impact on antifungal therapy (AFT), and gain an improved understanding of the epidemiology of IC in our critical care unit (CrCU). METHODS: An AFS care pathway incorporating BDG was introduced in the CrCU in St James's Hospital, Dublin. Following an educational programme, compliance with the pathway was prospectively audited between December 1st, 2017 and July 31st, 2018. RESULTS AND CONCLUSION: One hundred and nine AFT episodes were included, of which 95 (87%) had a BDG sent. Of those with BDG results available at the time of decision-making, 38 (63%) were managed in accordance with the care pathway. In compliant episodes without IC, median EAFT duration was 5.5 days [IQR 4-7] and no increase in mortality or subsequent IC was observed. Although adopting a diagnostics-driven approach was found to be useful in the cohort of patients with BDG results available, the use of once-weekly BDG testing did not result in an observed reduction in the consumption of anidulafungin, highlighting an important limitation of this approach.

10.
Physiotherapy ; 105(3): 328-337, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30318127

RESUMEN

OBJECTIVE: To explore how physiotherapists currently address analgesic use among patients with hip osteoarthritis, and their beliefs about the acceptability of prescribing for these patients. METHODS: A cross-sectional questionnaire was mailed to 3126 UK-based physiotherapists. Approaches to analgesic use among patients with hip osteoarthritis were explored using a case vignette. Semi-structured telephone interviews were undertaken with 21 questionnaire responders and analysed thematically. SETTING: UK. PARTICIPANTS: Physiotherapists who had treated a patient with hip osteoarthritis in the previous 6 months. RESULTS: Questionnaire response: 53% (n=1646). One thousand one hundred forty eight physiotherapists reported treating a patient with hip osteoarthritis in the last 6 months (applicable responses), of whom nine (1%) were non-medical prescribers. Nearly all physiotherapists (98%) reported that they would address analgesic use for the patient with hip osteoarthritis, most commonly by signposting them to their GP (83%). Fifty six percent would discuss optimal use of current medication, and 33%, would discuss use of over-the-counter medications. Interviews revealed that variations in physiotherapists' approaches to analgesic use were influenced by personal confidence, patient safety concerns, and their perceived professional remit. Whilst many recognised the benefits of analgesia prescribing for both patients and GP workload, additional responsibility for patient safety was a perceived barrier. CONCLUSIONS: How physiotherapists currently address analgesic use with patients with hip osteoarthritis is variable. Although the potential benefits of independent prescribing were recognised, not all physiotherapist want the additional responsibility. Further guidance supporting optimisation of analgesic use among patients with hip OA may help better align care with best practice guidelines and reduce GP referrals.


Asunto(s)
Analgésicos/uso terapéutico , Osteoartritis de la Cadera/tratamiento farmacológico , Fisioterapeutas , Estudios Transversales , Femenino , Humanos , Masculino , Manejo del Dolor , Relaciones Profesional-Paciente , Encuestas y Cuestionarios , Reino Unido
11.
Physiol Behav ; 94(1): 17-28, 2008 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-18155097

RESUMEN

It is becoming increasingly apparent that conditions experienced in early life play an important role in the long-term health of individuals. Alterations in development due to impaired, excessive or imbalanced growth, both in utero and during critical periods of relative plasticity beyond birth, can lead to the permanent programming of physiological systems. The regulation of energy balance is one area that is receiving particular attention, as rates of obesity and associated metabolic and cardiovascular disease continue to rise. Over recent decades, much progress has been made toward understanding the way in which metabolic tissues and physiological systems develop, and the impact of early life events and nutrition on these processes. It is apparent within human populations that some individuals are better able to maintain an appropriate body weight in the face of an obesogenic environment. Animal models have been widely used for the investigation of differential susceptibility to diet-induced obesity (DIO) and impaired energy balance regulation, and are shedding light on key pathways that may be involved. Alterations in pathways mediating energy homeostasis, outlined below, are likely candidates for programming effects following disturbed growth in early life.


Asunto(s)
Enfermedades Metabólicas/fisiopatología , Obesidad/fisiopatología , Tejido Adiposo/crecimiento & desarrollo , Tejido Adiposo/fisiología , Animales , Dieta , Modelos Animales de Enfermedad , Metabolismo Energético/fisiología , Femenino , Glucocorticoides/fisiología , Crecimiento/fisiología , Homeostasis/fisiología , Humanos , Leptina/fisiología , Hipernutrición/fisiopatología , Fenotipo , Embarazo
12.
Nat Commun ; 8: 14062, 2017 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-28082738

RESUMEN

The amount of carbon present in Earth's mantle affects the dynamics of melting, volcanic eruption style and the evolution of Earth's atmosphere via planetary outgassing. Mantle carbon concentrations are difficult to quantify because most magmas are strongly degassed upon eruption. Here we report undegassed carbon concentrations from a new set of olivine-hosted melt inclusions from the Mid-Atlantic Ridge. We use the correlations of CO2 with trace elements to define an average carbon abundance for the upper mantle. Our results indicate that the upper mantle carbon content is highly heterogeneous, varying by almost two orders of magnitude globally, with the potential to produce large geographic variations in melt fraction below the volatile-free solidus. Such heterogeneity will manifest as variations in the depths at which melt becomes interconnected and detectable, the CO2 fluxes at mid-ocean ridges, the depth of the lithosphere-asthenosphere boundary, and mantle conductivity.

13.
Contemp Clin Trials ; 52: 35-38, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27836506

RESUMEN

Primary care patient-centered medical homes (PCMHs) are an effective healthcare delivery model. Evidence regarding the most effective payment models for increased coordination efforts is sparse. This protocol paper describes the evaluation of an Alternative Payment Methodology (APM) implemented in a subset of Oregon community health centers (CHCs), using a prospective matched observational design. The APM is a primary care payment reform intervention that changed Oregon's Medicaid payment for several CHCs from fee-for-service reimbursement to a per-member-per-month capitated payment. We will implement a difference-in-difference analytic approach to evaluate pre-post APM changes between intervention and control groups, including: 1) clinic-level outcomes, 2) patient-level clinical outcomes, and 3) patient-level econometric outcomes. Findings from the project will be of national significance, as there is a need for evidence regarding how novel payment methods might enhance PCMH capabilities and support their capacity to produce better quality and outcomes. If this capitated payment method is proven effective, study findings will inform dissemination of similar APMs nationwide.


Asunto(s)
Capitación , Centros Comunitarios de Salud/organización & administración , Atención Dirigida al Paciente/organización & administración , Atención Primaria de Salud/organización & administración , Centros Comunitarios de Salud/economía , Planes de Aranceles por Servicios , Humanos , Medicaid , Oregon , Atención Dirigida al Paciente/economía , Atención Primaria de Salud/economía , Estudios Prospectivos , Mecanismo de Reembolso , Estados Unidos
14.
Respir Res ; 7: 88, 2006 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-16776827

RESUMEN

BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a debilitating disease characterized by exaggerated extracellular matrix deposition and aggressive lung structural remodeling. Disease pathogenesis is driven by fibroblastic foci formation, consequent on growth factor overexpression and myofibroblast proliferation. We have previously shown that both CTGF overexpression and myofibroblast formation in IPF cell lines are dependent on RhoA signaling. As RhoA-mediated regulation is also involved in cell cycle progression, we hypothesise that this pathway is key to lung fibroblast turnover through modulation of cyclin D1 kinetic expression. METHODS: Cyclin D1 expression was compared in primary IPF patient-derived fibroblasts and equivalent normal control cells. Quantitative real time PCR was employed to examine relative expression levels of cyclin D1 mRNA; protein expression was confirmed by western blotting. Effects of Rho signaling were investigated using transient transfection of constitutively active and dominant negative RhoA constructs as well as pharmacological inhibitors. Cellular proliferation of lung fibroblasts was determined by BrdU incorporation ELISA. To further explore RhoA regulation of cyclin D1 in lung fibroblasts and associated cell cycle progression, an established Rho inhibitor, Simvastatin, was incorporated in our studies. RESULTS: Cyclin D1 expression was upregulated in IPF compared to normal lung fibroblasts under exponential growth conditions (p < 0.05). Serum deprivation inhibited cyclin D1 expression, which was restored following treatment with fibrogenic growth factors (TGF-beta1 and CTGF). RhoA inhibition, using a dominant negative mutant and a pharmacological inhibitor (C3 exotoxin), suppressed levels of cyclin D1 mRNA and protein in IPF fibroblasts, with significant abrogation of cell turnover (p < 0.05). Furthermore, Simvastatin dose-dependently inhibited fibroblast cyclin D1 gene and protein expression, inducing G1 cell cycle arrest. Similar trends were observed in control experiments using normal lung fibroblasts, though exhibited responses were lower in magnitude. CONCLUSION: These findings report for the first time that cyclin D1 expression is deregulated in IPF through a RhoA dependent mechanism that influences lung fibroblast proliferation. This potentially unravels new molecular targets for future anti-IPF strategies; accordingly, Simvastatin inhibition of Rho-mediated cyclin D1 expression in IPF fibroblasts merits further exploitation.


Asunto(s)
Ciclina D1/genética , Fibroblastos/metabolismo , Fibrosis Pulmonar/metabolismo , Transducción de Señal/fisiología , Proteína de Unión al GTP rhoA/metabolismo , ADP Ribosa Transferasas/farmacología , Toxinas Botulínicas/farmacología , División Celular/efectos de los fármacos , División Celular/fisiología , Línea Celular , Factor de Crecimiento del Tejido Conjuntivo , Ciclina D1/metabolismo , Fibroblastos/patología , Fase G1/efectos de los fármacos , Fase G1/fisiología , Expresión Génica/fisiología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Proteínas Inmediatas-Precoces/farmacología , Péptidos y Proteínas de Señalización Intercelular/farmacología , Pulmón/citología , Fibrosis Pulmonar/patología , Transducción de Señal/efectos de los fármacos , Simvastatina/farmacología , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta1 , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología , Proteína de Unión al GTP rhoA/antagonistas & inhibidores
15.
Placenta ; 48 Suppl 1: S3-S6, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-26693894

RESUMEN

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2015 there were twelve themed workshops, three of which are summarized in this report. These workshops covered areas of placental regulation and nutrient handling: 1) placental epigenetics; 2) placental mitochondrial function; 3) placental transport systems.


Asunto(s)
Epigénesis Genética , Mitocondrias/metabolismo , Placenta/metabolismo , Placentación/fisiología , Animales , Transporte Biológico/fisiología , Femenino , Humanos , Embarazo
16.
Placenta ; 36(6): 638-44, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25862611

RESUMEN

INTRODUCTION: Potassium (K(+)) channels are key regulators of vascular smooth muscle cell (VSMC) excitability. In systemic small arteries, Kv7 channel expression/activity has been noted and a role in vascular tone regulation demonstrated. We aimed to demonstrate functional Kv7 channels in human fetoplacental small arteries. METHODS: Human placental chorionic plate arteries (CPAs) were obtained at term. CPA responses to Kv7 channel modulators was determined by wire myography. Presence of Kv7 channel mRNA (encoded by KCNQ1-5) and protein expression were assessed by RT-PCR and immunohistochemistry/immunofluorescence, respectively. RESULTS: Kv7 channel blockade with linopirdine increased CPA basal tone and AVP-induced contraction. Pre-contracted CPAs (AVP; 80 mM K(+) depolarization solution) exhibited significant relaxation to flupirtine, retigabine, the acrylamide (S)-1, and (S) BMS-204352, differential activators of Kv7.1 - Kv7.5 channels. All CPAs assessed expressed KCNQ1 and KCNQ3-5 mRNA; KCNQ2 was expressed only in a subset of CPAs. Kv7 protein expression was confirmed in intact CPAs and isolated VSMCs. DISCUSSION: Kv7 channels are present and active in fetoplacental vessels, contributing to vascular tone regulation in normal pregnancy. Targeting these channels may represent a therapeutic intervention in pregnancies complicated by increased vascular resistance.


Asunto(s)
Arterias/fisiología , Canales de Potasio KCNQ/agonistas , Canales de Potasio KCNQ/metabolismo , Músculo Liso Vascular/fisiología , Placenta/irrigación sanguínea , Vasodilatación/fisiología , Arterias/efectos de los fármacos , Femenino , Humanos , Indoles/farmacología , Canales de Potasio KCNQ/antagonistas & inhibidores , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/fisiología , Bloqueadores de los Canales de Potasio/farmacología , Embarazo , Piridinas/farmacología , Vasodilatación/efectos de los fármacos
17.
J Thorac Cardiovasc Surg ; 96(4): 535-41, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2459560

RESUMEN

Contact between blood and artificial surfaces results in extensive quantitative and qualitative alterations in platelet function. We evaluated the efficacy of a brief infusion of iloprost (ZK36374), a stable analog of prostacyclin, in preventing these platelet changes during extracorporeal membrane oxygenation. Twelve nonsplenectomized male mongrel dogs (23 to 30 kg) were randomized to treatment (n = 6) and control (n = 6) groups. The treatment animals received an infusion of iloprost at a rate of 150 ng/kg/min with the infusion being terminated 30 minutes after the initiation of extracorporeal membrane oxygenation, despite the fact that all animals were maintained on extracorporeal membrane oxygenation for 3 hours. In the control group, platelet counts dropped to 54% +/- 8.9% (mean +/- standard error of the mean) of initial levels at 30 minutes of extracorporeal membrane oxygenation and gradually rose to 87.2% +/- 6.7% at 3 hours. In contrast, the platelet counts of the iloprost-treated dogs remained stable throughout extracorporeal membrane oxygenation at 98.3% +/- 4.2% of initial counts. Platelet reactivity toward adenosine diphosphate revealed a significant and permanent loss of platelet function in the control group (37.0% +/- 2.1% inhibition). In contrast, the iloprost group demonstrated significant inhibition of platelet reactivity (79.2% +/- 8.3%) during the iloprost infusion but a return to normal function (4.2% +/- 6.7% inhibition) after cessation of drug infusion which persisted throughout extracorporeal membrane oxygenation. Plasma levels of the platelet-specific protein thrombospondin rose progressively from 918 +/- 89 ng/ml to 1465 +/- 239 ng/ml (delta 548 +/- 179 ng/ml) at 30 minutes of extracorporeal membrane oxygenation, which indicates extensive release of platelet granule contents (p less than 0.05). In contrast, plasma thrombospondin levels in the iloprost group demonstrated no additional rise after cessation of the iloprost infusion. In conclusion, iloprost effectively preserves platelet number and function during extracorporeal circulation. The fact that its salutary effects outlast its presence in plasma suggests that prevention of initial platelet-synthetic surface interactions permits the appearance of reduced surface affinity for platelets and, thus, reduced synthetic surface thrombogenicity.


Asunto(s)
Plaquetas/efectos de los fármacos , Fármacos Cardiovasculares/uso terapéutico , Epoprostenol/uso terapéutico , Oxigenación por Membrana Extracorpórea , Animales , Plaquetas/metabolismo , Perros , Glicoproteínas/sangre , Iloprost , Masculino , Recuento de Plaquetas/efectos de los fármacos , Pruebas de Función Plaquetaria , Trombospondinas , Factores de Tiempo
18.
J Thorac Cardiovasc Surg ; 94(3): 405-13, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2442566

RESUMEN

For patients with heparin-induced platelet activation, reexposure to heparin can result in profound thrombocytopenia, intravascular thrombosis, and hemorrhage. We compared the ability of aspirin to that of iloprost (ZK36374), an analogue of prostacyclin, in preventing heparin-induced platelet activation and thus permitting a cardiac operation in a patient with heparin-induced platelet activation. Despite abolishing thromboxane A2 synthesis, aspirin (4 mmol/L) failed to prevent either in vitro heparin-induced platelet aggregation (65.0% without versus 59% with aspirin) or carbon 14-serotonin release (81.8% without versus 59.7% with aspirin). In contrast, iloprost (0.01 mumol/L) prevented both in vitro heparin-induced platelet aggregation (65% without versus 5.0% with iloprost) and release (81.8% without versus 0% with iloprost). Consequently, a continuous infusion of iloprost was begun before administration of heparin, continued throughout cardiopulmonary bypass, and discontinued 15 minutes after administration of protamine. The whole blood platelet count (209,000/microliter) remained stable after intraoperative administration of heparin (238,000/microliter) and was 115,000/microliter after the operation. No spontaneous platelet aggregates were observed in samples of platelet-rich plasma after heparin administration, and no platelet transfusions were required. Plasma levels of platelet factor 4 rose from 27 to 725 ng/ml after heparin administration but then declined during bypass to 50 ng/ml. Beta thromboglobulin levels only rose from 92 to 496 ng/ml with administration of heparin. Fibrinopeptide A levels fell from 72 to 22 ng/ml after heparin and remained stable throughout bypass. The template bleeding time was 7.5 minutes preoperatively and 8.0 minutes postoperatively. The postoperative chest tube drainage (12 hours) was 475 ml, and platelets responded normally to adenosine diphosphate. In conclusion, iloprost but not aspirin completely prevented heparin-induced platelet activation in vitro. Furthermore, iloprost effectively prevented this syndrome clinically, which permitted a safe cardiac operation in this patient with heparin-induced platelet activation.


Asunto(s)
Aspirina/uso terapéutico , Plaquetas/efectos de los fármacos , Procedimientos Quirúrgicos Cardíacos/métodos , Epoprostenol/uso terapéutico , Antagonistas de Heparina/uso terapéutico , Anciano , Femenino , Humanos , Iloprost
19.
Metabolism ; 48(11): 1424-31, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10582552

RESUMEN

Aging is associated with decreased growth hormone (GH) secretion and plasma insulin-like growth factor-I (IGF-I) levels, increased total and abdominal fat, total and low-density lipoprotein (LDL) cholesterol, and triglycerides, and reduced high-density lipoprotein (HDL) cholesterol. Similar changes in lipids and body composition occur in nonelderly GH-deficient adults and are reversed with GH administration. To examine whether GH/IGF-I axis function in the elderly is related to the lipid profile independently of body fat, we evaluated GH secretion, serum IGF-I and IGF binding protein-3 (IGFBP-3) levels, adiposity via the body mass index (BMI), waist to hip ratio (WHR), dual-energy x-ray absorptiometry (DEXA), and magnetic resonance imaging (MRI), and circulating lipids in 101 healthy subjects older than 65 years. Integrated nocturnal GH secretion (log IAUPGH) was inversely related (P < .005) to DEXA total and abdominal fat and MRI visceral fat in both genders. Log IAUPGH was inversely related to visceral fat in women (P < .005) and men (P < .0001), but was not significantly related to total fat in either gender. In women, log IAUPGH was related inversely to total and LDL cholesterol and positively to HDL cholesterol (P < .008). In men, log IAUPGH was inversely related to total cholesterol and triglycerides (P < .005). In women, HDL cholesterol was inversely related to the WHR (P < .005). In men, triglycerides were positively related (P < .001) to the WHR and DEXA abdominal and MRI visceral fat. Multivariate regression revealed log IAUPGH, but not DEXA total body fat, to be an independent determinant of total (P < .001 for women and P = .01 for men) and LDL (P < .007 and P = .05) cholesterol in both sexes and of HDL cholesterol (P < .005) and triglycerides (P < .03) in women. Log IAUPGH, but not DEXA abdominal fat, was related to total (P < .005 and P < .03) and LDL (P < .03 and P = .05) cholesterol in both genders and to HDL in women (P < .05). Log IAUPGH, but not MRI visceral fat, was related to total cholesterol (P < .03 and P = .05) in women and men. Age, IGF-I, and IGFBP-3 were not significantly related to any body fat or lipid measures, except for a positive correlation of IGF-I with triglycerides in men. Thus, endogenous nocturnal GH secretion predicts total, LDL, and HDL cholesterol levels independently of total or abdominal fat, suggesting that it is an independent cardiometabolic risk factor in healthy elderly people.


Asunto(s)
Tejido Adiposo , Composición Corporal , Hormona de Crecimiento Humana/sangre , Lípidos/sangre , Absorciometría de Fotón , Anciano , Constitución Corporal , Índice de Masa Corporal , Colesterol/sangre , Estudios Transversales , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Imagen por Resonancia Magnética , Masculino , Análisis Multivariante , Valores de Referencia , Triglicéridos/sangre
20.
J Appl Physiol (1985) ; 87(6): 2136-42, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10601160

RESUMEN

Using external vascular ultrasound, we measured brachial artery diameter (Diam) at rest, after release of 4 min of limb ischemia, i. e., endothelium-dependent dilation (EDD), and after sublingual nitroglycerin, i.e., non-endothelium-dependent dilation (NonEDD), in 35 healthy men aged 61-83 yr: 12 endurance athletes (A) and 23 controls (C). As anticipated, treadmill exercise maximal oxygen consumption (VO(2 max)) was significantly higher in A than in C (40. 2 +/- 6.6 vs. 27.9 +/- 3.8 ml. kg(-1). min(-1); respectively, P < 0. 0001). With regard to arterial physiology, A had greater EDD (8.9 +/- 4.2 vs. 5.7 +/- 3.5%; P = 0.02) and a tendency for higher NonEDD (13.9 +/- 6.7 vs. 9.7 +/- 4.2%; P = 0.07) compared with C. By multiple linear regression analysis in the combined sample of older men, only baseline Diam (beta = -2.0, where beta is the regression coefficient; P = 0.005) and VO(2 max) (beta = 0.23; P = 0.003) were independent predictors of EDD; similarly, only Diam (beta = -4.0; P = 0.003) and VO(2 max) (beta = 0.27; P = 0.01) predicted NonEDD. Thus endurance-trained older men demonstrate both augmented EDD and NonEDD, consistent with a generalized enhanced vasodilator responsiveness, compared with their sedentary age peers.


Asunto(s)
Endotelio Vascular/fisiología , Educación y Entrenamiento Físico , Resistencia Física , Sistema Vasomotor/fisiología , Anciano , Anciano de 80 o más Años , Ejercicio Físico/fisiología , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Valores de Referencia , Análisis de Regresión , Vasodilatación/fisiología
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