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1.
Med Teach ; 35(9): e1464-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23527865

RESUMEN

BACKGROUND: Training in patient safety is an important element of medical education. Most educational interventions on patient safety training adopt a 'health-professional lens' with limited consideration on the impact of safety lapses on the patient and their families and little or no involvement of patients in the design or delivery of the training. AIMS: This paper describes a pilot study to test the feasibility and acceptability of implementing a patient-led educational intervention to facilitate safety training amongst newly qualified doctors. METHOD: Patients and/or carers who had experienced harm during their care shared narratives of their stories with trainees; this was followed by a focused discussion on patient safety issues exploring the causes and consequences of safety incidents and lessons to be learned from these. RESULTS: The intervention, which will be further tested in an NIHR-funded randomised controlled trial (RCT), was successfully implemented into an existing training programme and found acceptance amongst the patients and trainees. CONCLUSION: The pilot study proved to be a useful step in refining the intervention for the RCT including identifying appropriate outcome measures and highlighting organisational issues.


Asunto(s)
Educación de Postgrado en Medicina/métodos , Seguridad del Paciente , Pacientes/psicología , Enseñanza/métodos , Adulto , Actitud del Personal de Salud , Curriculum , Estudios de Factibilidad , Femenino , Humanos , Masculino , Proyectos Piloto , Encuestas y Cuestionarios
2.
Nat Commun ; 9(1): 4906, 2018 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-30464173

RESUMEN

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have become a powerful tool for human disease modeling and therapeutic testing. However, their use remains limited by their immaturity and heterogeneity. To characterize the source of this heterogeneity, we applied complementary single-cell RNA-seq and bulk RNA-seq technologies over time during hiPSC cardiac differentiation and in the adult heart. Using integrated transcriptomic and splicing analysis, more than half a dozen distinct single-cell populations were observed, several of which were coincident at a single time-point, day 30 of differentiation. To dissect the role of distinct cardiac transcriptional regulators associated with each cell population, we systematically tested the effect of a gain or loss of three transcription factors (NR2F2, TBX5, and HEY2), using CRISPR genome editing and ChIP-seq, in conjunction with patch clamp, calcium imaging, and CyTOF analysis. These targets, data, and integrative genomics analysis methods provide a powerful platform for understanding in vitro cellular heterogeneity.


Asunto(s)
Diferenciación Celular , Heterogeneidad Genética , Miocitos Cardíacos/metabolismo , Análisis de la Célula Individual/métodos , Potenciales de Acción , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factor de Transcripción COUP II/metabolismo , Señalización del Calcio , Humanos , Células Madre Pluripotentes Inducidas , Proteínas Represoras/metabolismo , Análisis de Secuencia de ARN , Proteínas de Dominio T Box/metabolismo , Transcriptoma
3.
J Clin Endocrinol Metab ; 84(7): 2336-41, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10404799

RESUMEN

The timing of the physical transition from child to adult is determined by a biological clock that switches off the pituitary gonadal axis during infancy until puberty. Body composition (and in particular, fat mass), through leptin, are critical signals to this clock. However, no direct relationship between leptin and puberty has been demonstrated. Leptin is bound in the circulation by a high-affinity binding protein, which has been identified as a soluble leptin receptor. We found circulating levels of leptin binding activity (LBA) to be low at birth, to be high in the prepubertal years, to fall through puberty, and then to remain stable during adult life. LBA correlated with pubertal status in both boys and girls. We postulate that the fall in LBA, associated with increasing age and puberty, reflects a reduction in expression of truncated leptin receptors, and leptin is then available to the full-length receptor, which transmits the biological signal for leptin. The high levels of LBA occur during the years when the pituitary gonadal axis is quiescent. Thus, the change in LBA could explain how leptin regulates puberty.


Asunto(s)
Envejecimiento/fisiología , Proteínas/metabolismo , Pubertad/fisiología , Receptores de Superficie Celular , Adolescente , Adulto , Anciano , Unión Competitiva , Índice de Masa Corporal , Proteínas Portadoras/metabolismo , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Recién Nacido , Leptina , Masculino , Persona de Mediana Edad , Unión Proteica , Proteínas/fisiología , Receptores de Leptina , Testículo/anatomía & histología , Testículo/crecimiento & desarrollo
4.
Psychiatr Genet ; 14(4): 191-4, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15564891

RESUMEN

Anorexia nervosa is an eating disorder of unknown aetiology. There is significant evidence for a genetic component in the pathogenesis of this disorder. A region on chromosome 1 has been identified as a susceptibility locus. The leptin receptor has been mapped to a similar region, further upstream of this susceptibility locus. Leptin and its receptor are known to be important factors in the control and regulation of body weight. Single nucleotide polymorphisms (SNPs) in the leptin receptor are associated with measures of body weight. In the present study, SNPs in the coding region of the leptin receptor were analysed and their possible association with anorexia nervosa was investigated. Two cohorts of young women, 176 Caucasian anorexia nervosa patients and 152 normal Caucasian females, were genotyped for three SNPs in the leptin receptor. There was no significant difference in allele or genotype frequency, for any SNP, between the normal controls and the cohort of anorexia subjects. There were no significant associations with any genotype and body mass index in either the control or anorexic cohorts. When the anorexic cohort was subdivided into restricting and bingeing/purging behaviours, we found no significant association with any genotype. Analysis of haplotypes showed no significant evidence of association with anorexia. In summary, leptin receptor SNPs do not appear to be important factors in the regulation of body weight in young, pre-menopausal women or have any significant association with anorexia nervosa.


Asunto(s)
Anorexia Nerviosa/genética , Polimorfismo de Nucleótido Simple , Receptores de Superficie Celular/genética , Adulto , Índice de Masa Corporal , Peso Corporal/genética , Codón/genética , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Premenopausia , Receptores de Leptina , Valores de Referencia
5.
Intensive Care Med ; 26(10): 1547-52, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11126270

RESUMEN

OBJECTIVE: Growth hormone (GH) given to reverse muscle catabolism in critical illness increased mortality, illustrating the need for better understanding of the pathophysiology of the GH axis. We describe the relationship between changes in plasma insulin-like growth factor-I (IGF-I) and growth hormone-binding protein (GHBP) levels and hepatic growth hormone-binding in rats with sepsis. DESIGN: Randomised, controlled study. SETTING: University research laboratory. SUBJECTS: One hundred and eleven male Wistar rats. INTERVENTION: Three groups of rats underwent caecal ligation and puncture (CLP) and three groups laparotomy only (LAP). Survivors were killed at 24, 72, and 96 h. All animals were starved during the study. Twelve rats were killed at the start of the experiment (baseline) and twelve (allowed food) at 96 h. MEASUREMENTS AND RESULTS: Plasma levels of IGF-I and GHBP and binding of 125I-labelled human GH in liver homogenates were measured. IGF-I fell significantly following both CLP and LAP; at 24 h, IGF-I levels were lower after CLP than LAP (950 +/- 74 vs 1,522 +/- 60 microg/l, P = < 0.001). GHBP increased at 24 h following both CLP and LAP (45.6 +/- 1.87 and 47.7 +/- 3.01 vs 38.7 +/- 1.98 ng/ml at baseline, P = < 0.05). In LAP animals GHBP fell to below baseline by 72 h, and significantly so by 96 h (33.5 +/- 1.43, P = < 0.05), whereas GHBP remained elevated 72 h following CLP, returning to baseline by 96 h. The density of GH-binding sites in liver tended to increase, following both CLP and LAP at both 24 and 96 h, but these changes failed to achieve statistical significance. CONCLUSION: Reduced IGF-I levels in sepsis in the rat are associated with elevations in GHBP and a trend to increased hepatic GH binding. This suggests that in sepsis 'GH resistance' is not associated with reduced GH receptor numbers.


Asunto(s)
Proteínas Portadoras/sangre , Modelos Animales de Enfermedad , Factor I del Crecimiento Similar a la Insulina/metabolismo , Sepsis/sangre , Animales , Ciego/cirugía , Enfermedad Crítica , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Laparotomía , Ligadura , Hígado/química , Masculino , Punciones , Distribución Aleatoria , Ratas , Ratas Wistar , Inanición/metabolismo , Factores de Tiempo
6.
J Pediatr Endocrinol Metab ; 15(7): 963-71, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12199340

RESUMEN

Marked disturbance in eating behaviour and obesity are common sequelae of hypothalamic damage. To investigate whether these were associated with dysfunctional leptin central feedback, we evaluated serum leptin and leptin binding activity in 37 patients (age 3.5-21 yr) with tumour or trauma involving the hypothalamic-pituitary axis compared with 138 healthy children (age 5.0-18.2 yr). Patients were subdivided by BMI <2 SDS or > or = 2 SDS and healthy children and children with simple obesity of comparable age and pubertal status served as controls. Patients had higher BMI (mean 1.9 vs 0.2 SDS; p <0.001), a greater proportion had BMI > or = 2 SDS (54% vs 8%; p <0.001) and higher serum leptin (mean 2.1 vs 0.04 SDS; p <0.001) than healthy children. Serum leptin (mean 1.1 vs -0.1 SDS; p = 0.004) and values adjusted for BMI (median 0.42 vs 0.23 microg/l:kg/m2; p = 0.02) were higher in patients with BMI <2 SDS. However, serum leptin adjusted for BMI was similar in patients with BMI > or = 2 SDS compared to corresponding controls (1.08 vs 0.95; p = 0.6). Log serum leptin correlated with BMI SDS in all subject groups but the relationship in patients with BMI <2 SDS was of higher magnitude (r = 0.65, slope = 0.29, p =0.05 for difference between slopes) than in healthy controls (r = 0.42, slope = 0.19). Serum leptin binding activity (median 7.5 vs 9.3%; p = 0.02) and values adjusted for BMI (median 0.28 vs 0.48 % x m2/kg; p <0.001) were lower in patients than in healthy children. The markedly elevated leptin levels with increasing BMI in non-obese patients with hypothalamic-pituitary damage are suggestive of an unrestrained pattern of leptin secretion. This along with low leptin binding activity and hence higher free leptin levels would be consistent with central leptin insensitivity.


Asunto(s)
Enfermedades Hipotalámicas/sangre , Leptina/sangre , Receptores de Superficie Celular/sangre , Tejido Adiposo/patología , Adolescente , Índice de Masa Corporal , Niño , Femenino , Humanos , Enfermedades Hipotalámicas/patología , Leptina/metabolismo , Masculino , Radioterapia , Receptores de Superficie Celular/metabolismo , Receptores de Leptina
7.
Br J Biomed Sci ; 56(1): 16-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10492910

RESUMEN

Leptin is a protein, produced by adipose tissue, which has cytokine and hormonal properties. Serum leptin levels can be considered as a measure of body fat mass, and are involved in regulation of body weight. Previous studies suggest that leptin may have an additional role in reproduction, and there is also evidence for involvement in the hypothalamic-pituitary-gonadal axis. In this study, we investigate the possible changes in serum leptin concentration throughout the menstrual cycle. Samples were collected from apparently healthy, fertile women at different stages in their menstrual cycle, timed precisely according to the luteinising hormone (LH) surge. Mean serum leptin levels were significantly higher in the luteal phase (median 11.4 ng/mL) than in the follicular phase (median 10.0 ng/mL) (P < 0.001). In addition, mean serum leptin levels correlated with body mass index (r = 0.54, P < 0.05), but showed no correlation with luteal-phase progesterone levels. Results showed that levels of serum leptin vary during the menstrual cycle, and add to the mounting evidence that leptin has a role in reproduction. These fluctuations should be taken into account whenever studies are performed using female subjects.


Asunto(s)
Ciclo Menstrual/sangre , Proteínas/metabolismo , Adulto , Índice de Masa Corporal , Femenino , Fertilidad/fisiología , Humanos , Leptina
8.
Int J Gynecol Cancer ; 17(2): 447-54, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17316360

RESUMEN

Women in hereditary nonpolyposis colorectal cancer (HNPCC) families have up to a 71% lifetime risk for developing endometrial cancer (EC). This compares to the female lifetime risk for colorectal cancer (CRC) in HNPCC of 60%. The basis of HNPCC is an inherited mutation in a mismatch repair gene (MMR). Aspirin and COX2 inhibitors seem to have a chemoprotective effect on CRC in the general population and are the subject of prospective clinical studies in patients at high risk for CRC including HNPCC. There is no evidence that these agents have any protective effect against EC in the general population. This study investigated the effect of aspirin and a COX2 inhibitor (rofecoxib) on an HNPCC EC cell line model (Ishikawa) by assessing the effect on proliferation, apoptosis, the cell cycle, and MMR gene expression. Aspirin inhibits EC cell proliferation by inducing apoptosis and changes in the cell cycle. This effect is not mediated by changes in MMR gene (hMSH2) expression as assessed by quantitative reverse transcription-polymerase chain reaction. Rofecoxib inhibits EC cell proliferation; this did not appear to be mediated by induction of apoptosis, by alterations of the cell cycle, or by changes in MMR gene expression.


Asunto(s)
Apoptosis/efectos de los fármacos , Aspirina/uso terapéutico , Carcinoma/prevención & control , Ciclo Celular/efectos de los fármacos , Neoplasias Colorrectales Hereditarias sin Poliposis/prevención & control , Reparación de la Incompatibilidad de ADN/efectos de los fármacos , Neoplasias Endometriales/prevención & control , Lactonas/uso terapéutico , Sulfonas/uso terapéutico , Carcinoma/patología , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Inhibidores de la Ciclooxigenasa/farmacología , Inhibidores de la Ciclooxigenasa/uso terapéutico , Evaluación Preclínica de Medicamentos , Neoplasias Endometriales/patología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células Tumorales Cultivadas
9.
Int J Gynecol Cancer ; 16(3): 1393-400, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16803536

RESUMEN

Microsatellite instability (MSI) is the phenotypic molecular characteristic of the majority of tumors associated with the hereditary nonpolyposis colorectal cancer syndrome (HNPCC). Women in this group have an increased risk of endometrial cancer (EC). This study aimed to determine whether MSI could be demonstrated in blind endometrial samples from women with EC, HNPCC kindreds undergoing screening for EC, and women with normal endometrium. Twenty-four women with EC, 20 women from HNPCC kindreds, and 20 women undergoing gynecological surgery for benign indications underwent blind sampling. MSI analysis was performed by conventional polymerase chain reaction using fluorescent-labeled primers and automated analysis. Twelve microsatellites were studied with MSI defined as evident when novel alleles were seen in endometrial biopsy samples compared to genomic DNA. Of the 24 EC samples obtained, sufficient DNA for analysis was extracted in 17 cases. Three cases had evidence of MSI in at least 7/12 loci. None of the endometrium from the two other study groups revealed evidence of MSI. This is the first demonstration of MSI in blind endometrial biopsies. The ability to demonstrate MSI in heterogeneous endometrial samples suggests potential for the development of a novel EC screening tool for women in HNPCC kindreds.


Asunto(s)
Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/genética , Inestabilidad Genómica , Repeticiones de Microsatélite , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Carcinoma Endometrioide/diagnóstico , Carcinoma Endometrioide/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Cistadenocarcinoma Seroso/diagnóstico , Cistadenocarcinoma Seroso/patología , Neoplasias Endometriales/patología , Salud de la Familia , Femenino , Humanos , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Método Simple Ciego
10.
Law Hum Behav ; 21(6): 619-34, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9418383

RESUMEN

In Experiment 1, we videotaped elderly and younger adults (n = 69) reporting their memories of a crime video. The seniors were significantly less accurate than the younger adults. In Experiment 2, participants viewed the "testimony" videotapes and rated the elderly as less credible than the younger adults. In Experiment 3, participant-jurors (n = 302) evaluated transcribed testimonies provided by Experiment 1 participants. The ostensible age of the witnesses was manipulated. Thus, some participants read a senior's testimony believing it was provided by a younger adult and vice versa. Participants were apparently not biased by negative stereotypes of seniors' eyewitness capabilities.


Asunto(s)
Anciano/psicología , Actitud , Crimen/legislación & jurisprudencia , Recuerdo Mental , Adolescente , Adulto , Anciano de 80 o más Años , Crimen/psicología , Femenino , Humanos , Masculino , Estereotipo
11.
Hum Genet ; 108(3): 233-6, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11354636

RESUMEN

The human leptin (obese) receptor gene contains a number of single nucleotide polymorphisms, including GLN223ARG, which changes an amino acid on the extracellular region common to all isoforms of the receptor. Here, we demonstrate that, in postmenopausal Caucasian women, genotypes at that locus are associated with differences in body mass index (BMI), fat mass and serum leptin levels. Measurement of serum leptin-binding activity indicates that this may reflect changed receptor function associated with genotype. These observations indicate that functional variations in the leptin receptor gene are important factors in the regulation of adiposity and BMI.


Asunto(s)
Tejido Adiposo/metabolismo , Proteínas Portadoras/genética , Leptina/sangre , Polimorfismo de Nucleótido Simple , Receptores de Superficie Celular , Anciano , Análisis de Varianza , Unión Competitiva , Índice de Masa Corporal , Proteínas Portadoras/metabolismo , ADN/genética , Femenino , Genotipo , Humanos , Leptina/metabolismo , Posmenopausia , Receptores de Leptina , Población Blanca/genética
12.
Hum Reprod ; 16(9): 2008-13, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11527914

RESUMEN

BACKGROUND: Previous studies in humans and mice have suggested the importance of leptin in fetal growth. Recurrent miscarriage may be a result of abnormal placental and/or fetal development and therefore abnormal leptin levels may be associated with this form of pregnancy loss. METHODS: Leptin and leptin-binding activity (LBA) were measured in blood obtained from women who had a history of recurrent miscarriage (n = 53) during weeks 5-6 and 7-8 of pregnancy, and the concentrations were correlated with subsequent pregnancy outcome. RESULTS: Concentrations of leptin ranged from 1.4-62.8 ng/ml, but there was a strong correlation (r = 0.825, P < 0.001) between leptin values at weeks 5-6 and 7-8 in the same woman. Women who subsequently miscarried had significantly lower plasma leptin concentrations on both weeks 5-6 (13.34 +/- 2.1 ng/ml) (P < 0.05) and 7-8 (13.71 +/- 2.4 ng/ml) (P < 0.01) of pregnancy, than women who subsequently had a term birth (22.04 +/- 2.43 ng/ml week 5-6, 24.76 +/- 3.66 ng/ml week 7-8). LBA values ranged from 1-8.5% but there was no significant difference in LBA in blood obtained from women who subsequently miscarried or had a live birth. CONCLUSIONS: The significantly lower concentrations of leptin in women who subsequently miscarried suggest that leptin may play a role in preventing miscarriage. However, as there was a considerable overlap between the values of leptin in women who subsequently miscarried, and those that had a live birth, these measurements are of limited use in the prediction of pregnancy outcome in these women.


Asunto(s)
Aborto Habitual/sangre , Proteínas Portadoras/sangre , Leptina/sangre , Receptores de Superficie Celular , Aborto Espontáneo/sangre , Adulto , Femenino , Humanos , Trabajo de Parto , Concentración Osmolar , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Receptores de Leptina
13.
Am J Reprod Immunol ; 50(3): 224-31, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14629027

RESUMEN

PROBLEM: Leptin has a key role to play in human female reproduction. Its receptor is expressed highly throughout the reproductive tract. Cytokines have an important role in preparing the endometrium for implantation and leptin is known to modulate cytokine production in other tissues. We, therefore, investigated the possible role of leptin in endometrial growth and function. METHOD OF STUDY: Reverse transcriptase polymerase chain reaction and immunocytochemistry were used to determine the pattern of expression of leptin receptor isoforms in primary human endometrial epithelial and stromal cells in culture. The effect of leptin on cell growth and on the production of cytokines [Leukaemia Inhibitory Factor (LIF), interleukin 6 and tumour necrosis factor-alpha] and matrix metalloproteinases (MMP) (MMP2 and MMP-9) was also investigated. RESULTS: Expression of the long form of the leptin was restricted to the cultured endometrial, epithelial cells. Both cultured endometrial stromal and epithelial cells expressed the short and variant isoforms of the receptor. Incubation of epithelial and stromal cell cultures with varying concentrations of leptin (0-1000 ng/mL) had no significant effect on cell growth or levels of MMP-2 or MMP-9 production. Leptin also had no significant effect on cytokine production by epithelial cells. CONCLUSIONS: This study shows for the first time, the presence of leptin receptor isoforms on endometrial, epithelial and stromal cells in culture. Leptin had no effect on cytokine and MMP production by these cells. However, it is possible that leptin affects other factors within the endometrium not investigated here.


Asunto(s)
Citocinas/biosíntesis , Endometrio/enzimología , Endometrio/inmunología , Leptina/farmacología , Metaloproteinasas de la Matriz/biosíntesis , Receptores de Superficie Celular/metabolismo , Adulto , Células Cultivadas , Citocinas/inmunología , Endometrio/efectos de los fármacos , Femenino , Humanos , Inmunohistoquímica , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Superficie Celular/genética , Receptores de Leptina
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