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1.
Nature ; 625(7996): 760-767, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38092039

RESUMEN

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with ß-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.


Asunto(s)
Factor 15 de Diferenciación de Crecimiento , Hiperemesis Gravídica , Náusea , Vómitos , Animales , Femenino , Humanos , Ratones , Embarazo , Talasemia beta/sangre , Talasemia beta/metabolismo , Feto/metabolismo , Factor 15 de Diferenciación de Crecimiento/sangre , Factor 15 de Diferenciación de Crecimiento/metabolismo , Hormonas/sangre , Hormonas/metabolismo , Hiperemesis Gravídica/complicaciones , Hiperemesis Gravídica/metabolismo , Hiperemesis Gravídica/prevención & control , Hiperemesis Gravídica/terapia , Náusea/sangre , Náusea/complicaciones , Náusea/metabolismo , Placenta/metabolismo , Vómitos/sangre , Vómitos/complicaciones , Vómitos/metabolismo
2.
bioRxiv ; 2023 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-37398065

RESUMEN

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

3.
Diabet Med ; 38(8): e14395, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-32870520

RESUMEN

AIM: To identify predictors of type 2 diabetes remission in the intervention arm of DiRECT (Diabetes Remission Clinical Trial). METHODS: Participants were aged 20-65 years, with type 2 diabetes duration of <6 years and BMI 27-45 kg/m2 , and were not receiving insulin. Weight loss was initiated by total diet replacement (825-853 kcal/day, 3-5 months, shakes/soups), and weight loss maintenance support was provided for 2 years. Remissions (HbA1c <48 mmol/mol [<6.5%], without antidiabetes medications) in the intervention group (n = 149, mean age 53 years, BMI 35 kg/m2 ) were achieved by 68/149 participants (46%) at 12 months and by 53/149 participants (36%) at 24 months. Potential predictors were examined by logistic regression analyses, with adjustments for weight loss and effects independent of weight loss. RESULTS: Baseline predictors of remission at 12 and 24 months included being prescribed fewer antidiabetes medications, having lower triglyceride and gamma-glutamyl transferase levels, and reporting better quality of life with less anxiety/depression. Lower baseline HbA1c was a predictor at 12 months, and older age and male sex were predictors at 24 months. Being prescribed antidepressants predicted non-remission. Some, but not all effects were explained by weight loss. Weight loss was the strongest predictor of remission at 12 months (adjusted odds ratio per kg weight loss 1.24, 95% CI 1.14, 1.34; P < 0.0001) and 24 months (adjusted odds ratio 1.23, 95% CI 1.13, 1.35; P <0.0001). Weight loss in kilograms and percentage weight loss were equally good predictors. Early weight loss and higher programme attendance predicted more remissions. Baseline BMI, fasting insulin, fasting C-peptide and diabetes duration did not predict remission. CONCLUSIONS: Other than weight loss, most predictors were modest, and not sufficient to identify subgroups for which remission was not a worthwhile target.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Insulina/uso terapéutico , Calidad de Vida , Inducción de Remisión/métodos , Pérdida de Peso/fisiología , Adulto , Anciano , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Masculino , Persona de Mediana Edad , Pronóstico , Adulto Joven
4.
Bone ; 120: 38-43, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30292817

RESUMEN

PURPOSE: Adequate dietary protein intake is important for the maintenance of bone health; however, data in this area is ambiguous with some suggestion that high protein intake can have deleterious effects on bone health. The aim of the current study was to explore the associations of protein intake with bone mineral density (BMD). METHODS: We used baseline data from the UK Biobank (participants aged 40-69 years) to examine the association of protein intake with BMD (measured by ultrasound). These associations were examined, in women (n = 39,066) and men (n = 31,149), after adjustment for socio-demographic and lifestyle confounders and co-morbidities. RESULTS: Protein intake was positively and linearly associated with BMD in women (ß-coefficient 0.010 [95% CI 0.005; 0.015, p < 0.0001]) and men (ß-coefficient 0.008 [95% CI 0.000; 0.015, p = 0.044]); per 1.0 g/kg/day increment in protein intake, independently of socio-demographics, dietary factors and physical activity. CONCLUSIONS: The current data have demonstrated that higher protein intakes are positively associated with BMD in both men and women. This indicates that higher protein intakes may be beneficial for both men and women.


Asunto(s)
Bancos de Muestras Biológicas , Densidad Ósea/fisiología , Proteínas en la Dieta/administración & dosificación , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reino Unido
5.
Int J Cardiol ; 252: 24-30, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29249435

RESUMEN

BACKGROUND: Remote ischaemic preconditioning (RIPC) is a cardioprotective intervention invoking intermittent periods of ischaemia in a tissue or organ remote from the heart. The mechanisms of this effect are incompletely understood. We hypothesised that RIPC might enhance coronary vasodilatation by an endothelium-dependent mechanism. METHODS: We performed a prospective, randomised, sham-controlled, blinded clinical trial. Patients with stable coronary artery disease (CAD) undergoing elective invasive management were prospectively enrolled, and randomised to RIPC or sham (1:1) prior to angiography. Endothelial-dependent vasodilator function was assessed in a non-target coronary artery with intracoronary infusion of incremental acetylcholine doses (10-6, 10-5, 10-4mol/l). Venous blood was sampled pre- and post-RIPC or sham, and analysed for circulating markers of endothelial function. Coronary luminal diameter was assessed by quantitative coronary angiography. The primary outcome was the between-group difference in the mean percentage change in coronary luminal diameter following the maximal acetylcholine dose (Clinicaltrials.gov identifier: NCT02666235). RESULTS: 75 patients were enrolled. Following angiography, 60 patients (mean±SD age 57.5±8.5years; 80% male) were eligible and completed the protocol (n=30 RIPC, n=30 sham). The mean percentage change in coronary luminal diameter was -13.3±22.3% and -2.0±17.2% in the sham and RIPC groups respectively (difference 11.32%, 95%CI: 1.2- 21.4, p=0.032). This remained significant when age and sex were included as covariates (difference 11.01%, 95%CI: 1.01- 21.0, p=0.035). There were no between-group differences in endothelial-independent vasodilation, ECG parameters or circulating markers of endothelial function. CONCLUSIONS: RIPC attenuates the extent of vasoconstriction induced by intracoronary acetylcholine infusion. This endothelium-dependent mechanism may contribute to the cardioprotective effects of RIPC.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Precondicionamiento Isquémico Miocárdico/métodos , Anciano , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Electrocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento
6.
Int J Obes (Lond) ; 41(12): 1761-1768, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28736445

RESUMEN

BACKGROUND: Obesity is a multifactorial condition influenced by both genetics and lifestyle. The aim of this study was to investigate whether the association between a validated genetic profile risk score for obesity (GPRS-obesity) and body mass index (BMI) or waist circumference (WC) was modified by macronutrient intake in a large general population study. METHODS: This study included cross-sectional data from 48 170 white European adults, aged 37-73 years, participating in the UK Biobank. Interactions between GPRS-obesity and macronutrient intake (including total energy, protein, fat, carbohydrate and dietary fibre intake) and its effects on BMI and WC were investigated. RESULTS: The 93-single-nucleotide polymorphism (SNP) GPRS was associated with a higher BMI (ß: 0.57 kg m-2 per s.d. increase in GPRS (95% confidence interval: 0.53-0.60); P=1.9 × 10-183) independent of major confounding factors. There was a significant interaction between GPRS and total fat intake (P(interaction)=0.007). Among high-fat-intake individuals, BMI was higher by 0.60 (0.52, 0.67) kg m-2 per s.d. increase in GPRS-obesity; the change in BMI with GPRS was lower among low-fat-intake individuals (ß: 0.50 (0.44, 0.57) kg m-2). Significant interactions with similar patterns were observed for saturated fat intake (high ß: 0.66 (0.59, 0.73) versus low ß: 0.49 (0.42, 0.55) kg m-2, P(interaction)=2 × 10-4) and for total energy intake (high ß: 0.58 (0.51, 0.64) versus low ß: 0.49 (0.42, 0.56) kg m-2, P(interaction)=0.019), but not for protein intake, carbohydrate intake and fibre intake (P(interaction) >0.05). The findings were broadly similar using WC as the outcome. CONCLUSIONS: These data suggest that the benefits of reducing the intake of fats and total energy intake may be more important in individuals with high genetic risk for obesity.


Asunto(s)
Bancos de Muestras Biológicas , Grasas de la Dieta , Ingestión de Energía/fisiología , Predisposición Genética a la Enfermedad/epidemiología , Obesidad/epidemiología , Adulto , Anciano , Índice de Masa Corporal , Estudios Transversales , Femenino , Interacción Gen-Ambiente , Humanos , Masculino , Persona de Mediana Edad , Obesidad/genética , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Reino Unido/epidemiología
7.
Trials ; 18(1): 237, 2017 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-28545545

RESUMEN

BACKGROUND: Prior to commencing a randomised controlled trial, we conducted a focused ethnography to ensure that the trial was well suited to the proposed setting. METHODS: A six-month observation of a Child and Adolescent Mental Health Service site in the North-East of England was undertaken to observe the site procedures, staff culture and patient care pathways. During this period, documentary data were collected and interviews were conducted with key informants to provide insight into staff perceptions of the proposed trial. The data were coded using thematic analysis and the resulting themes were verified by a second coder. RESULTS: Seventeen documents were collected, 158 h of observation and six formal staff interviews were undertaken. Four themes emerged from the data; non-clinically orientated variation in practice, diagnosis, capacity and staff economy. Non-clinically orientated variation in practice occurred when staff decisions were based upon resource availability rather than on clinical judgement. Diagnosis demonstrated differing staff confidence in making diagnoses and in the treatment of patients who had received a diagnosis. Capacity consisted of the time to attend training and the psychological capacity to consider or incorporate learning into practice. Staff economy was characterised by staff changes and shortages. There was significant interaction between the themes, with staff economy emerging as a central barrier to research. The results directly informed adaptations to the trial protocol. CONCLUSIONS: An ethnographic approach has provided important insights into the individual, practical and organisational boundaries into which a trial would need to be implemented.


Asunto(s)
Servicios de Salud del Adolescente/organización & administración , Antropología Cultural , Servicios de Salud del Niño/organización & administración , Prestación Integrada de Atención de Salud/organización & administración , Depresión/terapia , Servicios de Salud Mental/organización & administración , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Proyectos de Investigación , Adolescente , Conducta del Adolescente , Servicios de Salud del Adolescente/normas , Antropología Cultural/normas , Actitud del Personal de Salud , Niño , Conducta Infantil , Servicios de Salud del Niño/normas , Competencia Clínica , Vías Clínicas/organización & administración , Prestación Integrada de Atención de Salud/normas , Depresión/diagnóstico , Depresión/psicología , Inglaterra , Conocimientos, Actitudes y Práctica en Salud , Humanos , Servicios de Salud Mental/normas , Admisión y Programación de Personal , Ensayos Clínicos Pragmáticos como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Proyectos de Investigación/normas , Factores de Tiempo , Carga de Trabajo , Lugar de Trabajo/psicología
8.
Ecotoxicol Environ Saf ; 143: 336-343, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28434758

RESUMEN

Rather than migrating, mallard ducks may choose to overwinter in northern cities on open-water thermal refuges, such as municipal wastewater treatment ponds, which in Edmonton, Canada, stay ≥10°C during frigid winter months. Refuging mallards spend appreciable time daily on these ponds and hydrate using secondary clarified municipal wastewater (SCEW). We aimed to determine if SCEW ingestion affected mallard health. To this end, we gavaged newly hatched mallards (domesticated Pekin strain) over their first month with SCEW, as well as water representing negative and positive controls (municipal tap water, and the primary active ingredient from birth control pills, 17α-ethinyl estradiol (EE2), respectively). The gavage of SCEW did not affect mass of the body, liver, spleen or heart, but was associated with small increases in beak and wing chord length. In the positive control, EE2 gavage caused similar responses, but also increased tarsus and phallus length. The increases likely owed to the stimulatory effects of estrogenic substances on bone and phallus development. For the biotransformation enzyme CYP2H1, gene expression was numerically increased by both SCEW and EE2. In terms of behavior, SCEW and EE2 gavage reduced two infrequently detected behaviours, pecking and resting alone. Our results suggest that SCEW ingestion would be unlikely to cause any overt health effects in adults, but may evoke subtle, covert effects nevertheless.


Asunto(s)
Conducta Animal/fisiología , Patos/fisiología , Fenómenos de Retorno al Lugar Habitual/fisiología , Estanques/química , Aguas Residuales/química , Contaminantes Químicos del Agua , Alberta , Animales , Ciudades , Patos/crecimiento & desarrollo , Patos/metabolismo , Ingestión de Alimentos , Etinilestradiol/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
9.
Int J Obes (Lond) ; 40(6): 1005-11, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26927315

RESUMEN

BACKGROUND/OBJECTIVES: The association of weight changes with cardiometabolic biomarkers in South Asians has been sparsely studied. SUBJECTS/METHODS: We measured cardiometabolic biomarkers at baseline and after 3 years in the Prevention of Diabetes and Obesity in South Asians Trial. We investigated the effect of a lifestyle intervention on biomarkers in the randomized groups. In addition, treating the population as a single cohort, we estimated the association between change in weight and change in biomarkers. RESULTS: Complete data were available at baseline and after 3 years in 151 participants. At 3 years, there was an adjusted mean reduction of 1·44 kg (95% confidence interval (95% CI): 0.18-2.71) in weight and 1.59 cm (95% CI: 0.08-3.09) in waist circumference in the intervention arm as compared with the control arm. There was no clear evidence of difference between the intervention and control arms in change of mean value of any biomarker. As a single cohort, every 1 kg weight reduction during follow-up was associated with a reduction in triglycerides (-1.3%, P=0.048), alanine aminotransferase (-2.5%, P=0.032), gamma-glutamyl transferase (-2.2%, P=0.040), leptin (-6.5%, P<0.0001), insulin (-3.7%, P=0.0005), fasting glucose (-0.8%, P=0.0071), 2-h glucose (-2.3%, P=0.0002) and Homeostatic Model Assessment of insulin resistance (HOMA-IR: -4.5%, P=0.0002). There was no evidence of associations with other lipid measures, tissue plasminogen activator, markers of inflammation or blood pressure. CONCLUSIONS: We demonstrate that modest weight decrease in SAs is associated with improvements in markers of total and ectopic fat as well as insulin resistance and glycaemia in South Asians at risk of diabetes. Future trials with more intensive weight change are needed to extend these findings.


Asunto(s)
Pueblo Asiatico , Biomarcadores/sangre , Enfermedades Cardiovasculares/etnología , Diabetes Mellitus Tipo 2/prevención & control , Obesidad Abdominal/prevención & control , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Análisis por Conglomerados , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/etnología , Diabetes Mellitus Tipo 2/etiología , Femenino , Predisposición Genética a la Enfermedad/etnología , Predisposición Genética a la Enfermedad/genética , Humanos , Resistencia a la Insulina , Grasa Intraabdominal , Masculino , Persona de Mediana Edad , Obesidad Abdominal/sangre , Obesidad Abdominal/complicaciones , Obesidad Abdominal/etnología , Factores de Riesgo , Escocia , Australia del Sur/etnología , Circunferencia de la Cintura
10.
Diabet Med ; 33(11): 1569-1574, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26887663

RESUMEN

AIMS: To investigate whether metformin therapy alters circulating aromatic and branched-chain amino acid concentrations, increased levels amino acid concentrations, increased levels of which have been found to predict Type 2 diabetes. METHODS: In the Carotid Atherosclerosis: Metformin for Insulin Resistance (CAMERA) study (NCT00723307), 173 individuals without Type 2 diabetes, but with coronary disease, were randomized to metformin (n=86) or placebo (n=87) for 18 months. Plasma samples, taken every 6 months, were analysed using quantitative nuclear magnetic resonance spectroscopy. Ten metabolites consisting of eight amino acids [three branched-chain (isoleucine, leucine, valine), three aromatic (tyrosine, phenylalanine, histidine) and two other amino acids (alanine, glutamine)], lactate and pyruvate were quantified and analysed using repeated-measures models. On-treatment analyses were conducted to investigate whether amino acid changes were dependent on changes in weight, fat mass or insulin resistance estimated using homeostasis model assessment (HOMA-IR). RESULTS: Tyrosine decreased [-6.1 µmol/l (95% CI -8.5, -3.7); P<0.0001], while alanine [42 umol/l (95% CI 25, 59); P<0.0001] increased in the metformin-treated group compared with the placebo-treated group. Decreases in phenylalanine [-2.0 µmol/l (95% CI -3.6, -0.3); P=0.018] and increases in histidine [2.3 µmol/l (95% CI 0.1, 4.6); P=0.045] were also observed in the metformin group, although these changes were less statistically robust. Changes in these four amino acids were not accounted for by changes in weight, fat mass or HOMA-IR values. Levels of branched-chain amino acids, glutamine, pyruvate and lactate were not altered by metformin therapy. CONCLUSIONS: Metformin therapy results in a sustained and specific pattern of changes in aromatic amino acid and alanine concentrations. These changes are independent of any effects on weight and insulin sensitivity. Any causal link to metformin's unexplained cardiometabolic benefit requires further study.


Asunto(s)
Aminoácidos/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Metformina/uso terapéutico , Adulto , Aminoácidos de Cadena Ramificada/sangre , Enfermedad Coronaria/sangre , Enfermedad Coronaria/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/tratamiento farmacológico , Método Doble Ciego , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Resistencia a la Insulina , Masculino , Persona de Mediana Edad , Placebos
11.
Bioorg Med Chem ; 20(24): 6929-39, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-23159039

RESUMEN

A major drawback of internalizing monoclonal antibodies (mAbs) radioiodinated with direct electrophilic approaches is that tumor retention of radioactivity is compromised by the rapid washout of iodo-tyrosine, the primary labeled catabolite for mAbs labeled via this strategy. In our continuing efforts to develop more versatile residualizing labels that could overcome this problem, we have designed SIB-DOTA, a prosthetic labeling template that combines the features of the prototypical, dehalogenation-resistant N-succinimidyl 3-iodobenzoate (SIB) with DOTA, a useful macrocyclic chelator for labeling with radiometals. Herein we describe the synthesis of the unlabeled standard of this prosthetic moiety, its protected tin precursor, and radioiodinated SIB-DOTA. An anti-EGFRvIII-reactive mAb, L8A4 was radiolabeled with [(131)I]SIB-DOTA in 27.1±6.2% (n=2) conjugation yields and its targeting properties to the same mAb labeled with [(125)I]SGMIB both in vitro and in vivo using U87MG·ΔEGFR cells and xenografts were compared. In vitro paired-label internalization assays showed that the intracellular radioactivity from [(131)I]SIB-DOTA-L8A4 was 21.4±0.5% and 26.2±1.1% of initially bound radioactivity at 16 and 24h, respectively. In comparison, these values for [(125)I]SGMIB-L8A4 were 16.7±0.5% and 14.9±1.1%. Similarly, the SIB-DOTA prosthetic group provided better tumor targeting in vivo than SGMIB over 8 d period. These results suggest that SIB-DOTA warrants further evaluation as a residualizing agent for labeling internalizing mAbs including those targeted to EGFRvIII.


Asunto(s)
Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/farmacocinética , Compuestos Heterocíclicos con 1 Anillo/química , Inmunotoxinas/química , Inmunotoxinas/farmacocinética , Yodobenzoatos/química , Radiofármacos/síntesis química , Animales , Anticuerpos Monoclonales/inmunología , Línea Celular Tumoral , Receptores ErbB/inmunología , Glioblastoma/inmunología , Glioblastoma/metabolismo , Compuestos Heterocíclicos con 1 Anillo/síntesis química , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Humanos , Radioisótopos de Yodo/química , Radioisótopos de Yodo/farmacocinética , Yodobenzoatos/síntesis química , Yodobenzoatos/farmacocinética , Marcaje Isotópico/métodos , Ratones , Ratones Endogámicos BALB C , Compuestos Organometálicos/química , Radiofármacos/química , Radiofármacos/inmunología , Radiofármacos/farmacocinética , Estaño/química , Distribución Tisular
12.
Diabetologia ; 55(5): 1240-3, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22398647

RESUMEN

There is emerging evidence of cross-talk between the myocardium and systemic metabolic pathways. In particular, there is interest in the potential metabolic effects of A-type and B-type natriuretic peptides (ANP and BNP), produced in the myocardial tissue in response to ventricular stretch and cardiac overload. This commentary provides an overview of the evidence that natriuretic peptides promote lipolysis and enhance adiponectin production. In addition, we review new and existing evidence that BNP may directly improve glucose control, or else lower glucose indirectly via enhanced capillary permeability or greater renal excretion. Further investigation of the links between natriuretic peptide and glycaemia would seem important given the potential to reveal novel mechanisms to treat diabetes.


Asunto(s)
Prueba de Tolerancia a la Glucosa , Natriuréticos/administración & dosificación , Péptido Natriurético Encefálico/administración & dosificación , Humanos , Masculino
13.
J Thromb Haemost ; 9(8): 1452-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21696538

RESUMEN

BACKGROUND: CD40 ligand(CD40L) is implicated in atherosclerotic plaque formation. OBJECTIVES: We investigated prospective associations between circulating soluble CD40L and myocardial infraction (MI) or stroke in an older general population cohort, accounting for established and novel cardiovascular risk factors. METHODS: Baseline serum CD40L (sCD40L) was measured in incident MI (n = 368) and stroke (n = 304) cases and two controls per case, 'nested' in prospective UK studies of 4252 men and 4286 women aged 60-79 years, sampled from general practices in Britain in 1998-2000, with 7-year follow-up for fatal and non-fatal MI and stroke. RESULTS: sCD40L was higher in smokers and negatively associated with lung function and positively associated with total cholesterol and markers of inflammation, but not with other established cardiovascular disease (CVD) risk factors. Geometric mean sCD40L levels did not differ between MI cases and controls (5.94 ng mL(-1) vs. 5.82 ng mL(-1); P = 0.5) or between stroke cases and controls (5.61 ng mL(-1) vs. 5.28 ng mL(-1), P = 0.1). There was no strong evidence for elevated risk of MI or stroke in multivariable models comparing participants in the top to those in the bottom third of sCD40L. Age-adjusted odds ratios (ORs) were 1.39 [95% confidence interval (CI) 0.98, 1.96] for MI and 1.16 (0.78, 1.73) for stroke. These attenuated to 1.24 (95% CI 0.86, 1.79) and 1.18 (0.78, 1.78), respectively, after adjustment for established and novel CVD risk factors. CONCLUSIONS: sCD40L is associated with other inflammatory markers but is not itself a strong independent risk marker for either stroke or MI.


Asunto(s)
Ligando de CD40/sangre , Mediadores de Inflamación/sangre , Infarto del Miocardio/epidemiología , Accidente Cerebrovascular/epidemiología , Factores de Edad , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Oportunidad Relativa , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/sangre , Factores de Tiempo , Reino Unido/epidemiología
14.
Atherosclerosis ; 208(2): 550-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19700161

RESUMEN

AIMS: Secondhand smoke (SHS) exposure is associated with elevated CHD risks. Yet the pathways through which this may operate have not been investigated in epidemiologic studies with objective SHS exposure measures and a wide range of CHD risk factors associated with active smoking. Therefore we investigate associations between SHS exposure and CHD risk factors, to clarify how SHS exposure may raise risk of CHD. METHODS: Cross-sectional population-based study of 5029 men and women aged 59-80 years from primary care practices in Great Britain. Smoking, behavioural and demographic information was reported in questionnaires; nurses made physical measurements and took blood samples for analysis of serum cotinine and markers of inflammation, hemostasis and endothelial dysfunction. RESULTS: Active cigarette smokers had lower albumin and higher triglycerides, CRP, IL-6, white cell count, fibrinogen, blood viscosity, factor VIII, VWF and t-PA than non-smokers. Among non-smokers, serum cotinine levels were independently positively associated with CRP, fibrinogen, factor VIII, VWF and t-PA and inversely associated with albumin, after adjustment for age, gender, social and behavioural factors. The differences in CRP, fibrinogen and albumin between cotinine < or =0.05 and >0.7 ng/ml were one-third to one half the size of differences between cotinine < or =0.05 ng/ml and current smokers, but were of similar magnitude for VWF and t-PA. CONCLUSIONS: Endothelial, inflammatory and haemostatic markers related to CHD risk showed independent associations with SHS exposure in the same direction as those for active smoking. Results aid understanding of the associations between SHS exposure and elevated CHD risks.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/etiología , Inflamación , Contaminación por Humo de Tabaco/efectos adversos , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Índice de Masa Corporal , Cotinina/sangre , Femenino , Hemostasis , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Riesgo , Factores Sexuales
15.
Rev Sci Tech ; 28(2): 771-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20128489

RESUMEN

Competency at graduation, in a variety of physical and attitudinal skills, is an essential outcome measure for courses training veterinary surgeons. The approach adopted by the Royal Veterinary College, London, to identify and define the expected skill competencies required of our veterinary undergraduates by the time of graduation is described. In addition, we demonstrate how this skill set was built into a framework that was aligned with other student learning objectives. This two-year project resulted in the publication of a day-one skills handbook, which was introduced to the college staff and students in 2007.


Asunto(s)
Competencia Clínica , Curriculum/normas , Educación en Veterinaria/normas , Medicina Veterinaria/normas , Animales , Medicina Basada en la Evidencia , Humanos , Aprendizaje Basado en Problemas
16.
Diabetologia ; 52(2): 235-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19030842

RESUMEN

AIMS/HYPOTHESIS: The aim of this prospective study was to determine whether circulating intercellular adhesion molecule (ICAM) 1, as a potential surrogate of 'endothelial activation', is more strongly associated with risk of vascular events than with incident diabetes. METHODS: We related baseline ICAM-1 levels to vascular events (866 CHD and stroke events in 5,685 participants) and incident diabetes (292 in 4,945 without baseline diabetes) in the elderly over 3.2 years of follow-up. RESULTS: ICAM-1 levels correlated positively with triacylglycerol but negatively with LDL- and HDL-cholesterol. ICAM-1 levels were higher in those who developed diabetes (388.6 +/- 1.42 vs 369.4 +/- 1.39 ng/ml [mean+/-SD], p = 0.011) and remained independently associated with new-onset diabetes (HR 1.84, 95% CI 1.26-2.69, p = 0.0015 per unit increase in log[ICAM-1] after adjusting for classical risk factors and C-reactive protein). By contrast, ICAM-1 levels were not significantly (p = 0.40) elevated in those who had an incident vascular event compared with those who remained event-free, and corresponding adjusted risk associations were null (HR 0.98, 95% CI 0.80-1.22, p = 0.89) in analyses adjusted for other risk factors. CONCLUSIONS/INTERPRETATION: We show that elevated ICAM-1 levels are associated with risk of incident diabetes in the elderly at risk, despite no association with incident cardiovascular disease risk. We suggest that perturbations in circulating ICAM-1 levels are aligned more towards diabetes risk.


Asunto(s)
Diabetes Mellitus/epidemiología , Endotelio Vascular/fisiología , Molécula 1 de Adhesión Intercelular/sangre , Infarto del Miocardio/epidemiología , Accidente Cerebrovascular/epidemiología , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus/sangre , Femenino , Estudios de Seguimiento , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Incidencia , Masculino , Infarto del Miocardio/sangre , Infarto del Miocardio/mortalidad , Pravastatina/uso terapéutico , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/mortalidad , Factores de Tiempo
17.
QJM ; 101(10): 785-91, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18676684

RESUMEN

BACKGROUND: Matrix metalloproteinase-9 (MMP-9) has a potential role in arterial plaque rupture, but its relation to risk of coronary heart disease (CHD) is uncertain. AIM: To determine whether circulating levels of serum MMP-9 are prospectively related to the risk of CHD in the general population. METHODS: We measured baseline MMP-9 levels in stored serum samples of subjects in a case-control study nested within a prospective study of 5661 men followed up for 16 years for CHD events (465 cases, 1076 controls). RESULTS: MMP-9 values were associated with cigarette smoking, and with several inflammatory and haemostatic markers, but not with age, body mass index, blood pressure or lipid measurements. Men in the top third of baseline MMP-9 levels had an age-adjusted odds ratio (OR) for CHD of 1.37 (95% CI 1.04-1.82) compared with those in the bottom third. Adjustment for conventional risk factors (smoking in particular) reduced the odds ratio to borderline significance: OR 1.28 (95% CI 0.95-1.74), while additional adjustment for two markers of generalized inflammation, interleukin-6 and C-reactive protein, further attenuated the association: OR 1.13 (0.82-1.56). CONCLUSION: Serum MMP-9 has a modest association with incident CHD in the general population, which is not independent of cigarette smoking exposure and circulating markers of generalized inflammation. MMP-9 is unlikely to be a clinically useful biomarker of CHD risk, but may still play a role in the pathogenesis of CHD.


Asunto(s)
Enfermedad Coronaria/etiología , Metaloproteinasa 9 de la Matriz/metabolismo , Factores de Edad , Anciano , Biomarcadores/metabolismo , Estudios de Casos y Controles , Enfermedad Coronaria/sangre , Enfermedad Coronaria/enzimología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
J Thromb Haemost ; 5(9): 1795-800, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17723116

RESUMEN

BACKGROUND: While meta-analyses of prospective studies have established that plasma levels of several hemostatic variables are associated with the risk of coronary heart disease (CHD), these have been suggested to be acute-phase reactant proteins. This study examines their associations with inflammatory markers [C-reactive protein (CRP) and interleukin-6 (IL-6)] and the effect of adjustment on their associations with CHD risk. METHODS AND RESULTS: In a nested case-control study, 247 CHD cases and 473 controls were matched for age and sex from 10 529 men and women in the Fletcher Challenge cohort. Plasma levels of all hemostatic variables except von Willebrand factor (VWF) and lipoprotein (a) [Lp(a)] showed significant associations with CRP and IL-6. Fibrinogen, VWF, tissue plasminogen activator antigen (t-PA), D-dimer, Lp(a), CRP and IL-6 levels were significantly associated with risk of CHD. After adjustment for conventional risk factors, CRP, D-dimer and IL-6 levels were significantly associated with risk of CHD. On further adjustments for the other six hemostatic and inflammatory variables these associations were reduced, but remained significant for D-dimer and IL-6; odds ratios (95% CI), comparing the highest to lowest third, were 3.10 (1.25-7.67) and 2.79 (1.11-6.99), respectively. CONCLUSION: The associations of plasma levels of some hemostatic variables (fibrinogen, VWF, t-PA and Lp(a); but not fibrin D-dimer) with CHD risk are attenuated when inflammatory markers (CRP and IL-6) as well as conventional risk factors are included in multivariable analyses. D-dimer and IL-6 each have the potential to increase the prediction of CHD, in addition to conventional risk factors.


Asunto(s)
Enfermedad Coronaria/complicaciones , Hemostasis , Inflamación/complicaciones , Adulto , Proteína C-Reactiva/análisis , Estudios de Cohortes , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Humanos , Inflamación/sangre , Lipoproteína(a)/sangre , Masculino , Persona de Mediana Edad , Factores de Riesgo , Activador de Tejido Plasminógeno/sangre , Factor de von Willebrand/análisis
19.
Virology ; 314(1): 147-60, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-14517068

RESUMEN

Recent epidemiological studies have found that women infected with both herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) type 16 or HPV-18 are at greater risk of developing cervical carcinoma compared to women infected with only one virus. However, it remains unclear if HSV-2 is a cofactor for cervical cancer or if HPV and HSV-2 interact in any way. We have studied the effect of HSV-2 infection on HPV-11 gene expression in an in vitro double-infection assay. HPV transcripts were down-regulated in response to HSV-2 infection. Two HSV-2 vhs mutants failed to reduce HPV-16 E1;E4 transcripts. We also studied the effect of HSV-2 infection on preexisting experimental papillomas in a vaginal epithelial xenograft model. Doubly infected grafts demonstrated papillomatous transformation and the classical cytopathic effect from HSV-2 infection. HPV and HSV DNA signals were mutually exclusive. These studies may have therapeutic applications for HPV infections and related neoplasms.


Asunto(s)
Regulación hacia Abajo , Herpes Genital/complicaciones , Herpesvirus Humano 2/patogenicidad , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/complicaciones , Proteínas Represoras , Proteínas Virales/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Regulación Viral de la Expresión Génica , Herpes Genital/virología , Humanos , Ratones , Ratones Desnudos , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/genética , Papillomaviridae/metabolismo , Infecciones por Papillomavirus/virología , Ribonucleasas , Trasplante de Tejidos , Trasplante Heterólogo , Células Tumorales Cultivadas , Vagina/virología , Proteínas Virales/genética
20.
Aquat Toxicol ; 58(3-4): 165-74, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12007872

RESUMEN

Bull trout (Salvelinus confluentus) have been listed recently as threatened in the United States under the federal Endangered Species Act. This species currently resides, or historically resided, in several waterways that either are impacted or are under threat of impact from metals mining activities. We conducted a 55-day sub-chronic (i.e. sublethal) cadmium (Cd) exposure in water at 30 mg l(-1) (as CaCO(3)) hardness, pH 7.5, and 8 degrees C. Exposures were conducted using six replicate exposure tanks for each of the six treatments (five Cd concentrations and one control). Measured Cd concentrations were <0.013 (control), 0.052, 0.089, 0.197, 0.383, and 0.786 microg Cd l(-1). Exposure to 0.786 microg Cd l(-1) caused increased mortality (37%) and reduced growth (28% reduction in weight change) in fish exposed for 55 days. All Cd exposure concentrations caused significant whole body accumulation of Cd compared with controls. Our results indicate that even though fish are significantly accumulating Cd in each non-control treatment, growth reductions in bull trout occurred only at Cd concentrations that also caused significant mortality. The Cd concentration that reduced growth and survival in this long-term exposure (0.786 microg Cd l(-1)) is greater than the recently-revised US federal aquatic life criteria (ALC) value for the corresponding hardness concentration (ALC=0.62 microg Cd l(-1) for acute effects and 0.11 microg Cd l(-1) for chronic effects).


Asunto(s)
Cadmio/toxicidad , Trucha/crecimiento & desarrollo , Contaminantes Químicos del Agua/toxicidad , Animales , Cadmio/análisis , Cadmio/farmacocinética , Exposición a Riesgos Ambientales , Femenino , Agua Dulce , Dosificación Letal Mediana , Masculino , Mortalidad , Distribución Tisular , Trucha/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética
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