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3.
Exp Gerontol ; 79: 37-45, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-26972634

RESUMEN

Modern cardiovascular risk prediction tools, which have their genesis in the Framingham Heart Study, have allowed more accurate risk stratification and targeting of treatments worldwide over the last seven decades. Better cardiovascular risk factor control during this time has led to a reduction in cardiovascular mortality and, at least in part, to improved life expectancy. As a result, western societies as a whole have seen a steady increase in the proportion of older persons in their populations. Unfortunately, several studies have shown that the same tools which have contributed to this increase cannot be reliably extrapolated for use in older generations. Recent work has allowed recalibration of existing models for use in older populations but these modified tools still require external validation before they can be confidently applied in clinical practice. Another complication is emerging evidence that aggressive risk factor modification in older adults, particularly more frail individuals, may actually be harmful. This review looks at currently available cardiovascular risk prediction models and the specific challenges faced with their use in older adults, followed by analysis of recent attempts at recalibration for this cohort. We discuss the issue of frailty, looking at our evolving understanding of its constituent features and various tools for its assessment. We also review work to date on the impact of frailty on cardiovascular risk modification and outline its potentially central role in determining the most sensible approach in older patients. We summarise the most promising novel markers of cardiovascular risk which may be of use in improving risk prediction in older adults in the future. These include markers of vascular compliance (such as aortic pulse wave velocity and pulse wave analysis), of endothelial function (such as flow mediated dilation, carotid intima-media thickness and coronary artery calcium scores), and also biochemical and circulating cellular markers.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Anciano , Biomarcadores/sangre , Enfermedades Cardiovasculares/prevención & control , Anciano Frágil , Evaluación Geriátrica/métodos , Humanos , Medición de Riesgo/métodos , Factores de Riesgo
4.
Scand J Med Sci Sports ; 24(3): e195-200, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24118123

RESUMEN

This study aimed to analyze the frequency, nature, and consequences of footballers playing matches while injured, and to examine the impact on injury surveillance findings. High levels of inter-rater reliability and content validity were established for a tool designed to document players who were already injured at the start of a match. The tool was implemented in three English football teams (a Championship, League 1, and League 2 team) for one season, using a "time loss" definition of injury. One hundred forty-three matches were surveyed, revealing 102 match appearances by players who were already injured. Almost half of all games featured at least one injured player, with episodes of playing with injury occurring more frequently and lasting longer in League 2 players compared with higher level players. No association was observed between the number of injured players starting matches and match outcome [χ(2) (4, N = 143) = 3.27, P = 0.514]. Fifteen percent of all injury episodes captured were only through prospective documentation of playing while injured. The findings show that both traumatic and overuse injuries are managed by footballers through competitive matches, and have important implications for aiding understanding of the epidemiology of injury in professional football.


Asunto(s)
Traumatismos en Atletas/epidemiología , Conducta Competitiva , Traumatismos Ocupacionales/epidemiología , Vigilancia de la Población , Fútbol/lesiones , Adulto , Trastornos de Traumas Acumulados/epidemiología , Documentación , Humanos , Reino Unido/epidemiología , Adulto Joven
5.
J Endocrinol ; 216(1): 99-109, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23086141

RESUMEN

The neuropeptide apelin is expressed in hypothalamic paraventricular and supraoptic nuclei and mediates its effects via activation of the apelin receptor (APJ). Evidence suggests a role for apelin and APJ in mediating the neuroendocrine response to stress. To understand the physiological role of APJ in regulation of the hypothalamic-pituitary-adrenal (HPA) axis, we measured ACTH and corticosterone (CORT) plasma levels in male and female mice lacking APJ (APJ knockout, APJ KO) and in wild-type controls, in response to a variety of acute stressors. Exposure to mild restraint, systemic injection of lipopolysaccharide (LPS), insulin-induced hypoglycaemia and forced swim (FS) stressors, elevated plasma ACTH and CORT levels in wild-type mice. Acute mild restraint significantly increased plasma ACTH and CORT to a similar level in APJ KO mice as in wild-type mice. However, an intact APJ was required for a conventional ACTH, but not CORT, response to LPS administration in male mice and to insulin-induced hypoglycaemia in male and female mice. In contrast, APJ KO mice displayed an impaired CORT response to acute FS stress, regardless of gender. These data indicate that APJ has a role in regulation of the HPA axis response to some acute stressors and has a gender-specific function in peripheral immune activation of the HPA axis.


Asunto(s)
Sistema Hipotálamo-Hipofisario/metabolismo , Células Neuroendocrinas/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Estrés Fisiológico , Estrés Psicológico/metabolismo , Hormona Adrenocorticotrópica/sangre , Hormona Adrenocorticotrópica/metabolismo , Animales , Receptores de Apelina , Ritmo Circadiano , Corticosterona/sangre , Corticosterona/metabolismo , Cruzamientos Genéticos , Modelos Animales de Enfermedad , Femenino , Sistema Hipotálamo-Hipofisario/inmunología , Sistema Hipotálamo-Hipofisario/patología , Hibridación in Situ , Masculino , Ratones , Ratones Noqueados , Proteínas Mutantes/metabolismo , Células Neuroendocrinas/inmunología , Células Neuroendocrinas/patología , Sistema Hipófiso-Suprarrenal/inmunología , Sistema Hipófiso-Suprarrenal/patología , Receptores Acoplados a Proteínas G/genética , Caracteres Sexuales , Estrés Psicológico/sangre , Estrés Psicológico/inmunología
6.
J Neuroendocrinol ; 23(1): 12-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20874763

RESUMEN

Vasopressin V1b receptor knockout (V1b⁻/⁻) mice were used to investigate a putative role for the V1b receptor (V1bR) in fluid regulation and in the hypothalamic-neurohypophysial system (HNS) and hypothalamic-pituitary-adrenal (HPA) axis responses to osmotic stress induced by water deprivation (WD). Male wild-type and V1b⁻/⁻ mice were housed in metabolic cages to allow determination of water intake and urine volume and osmolality. When provided with food and water ad lib., spontaneous urine volume and urine osmolality did not differ between genotypes. Similarly, WD for 24 h caused comparable decreases in urine volume and increases in urine osmolality irrespective of genotype. WD resulted in an increase in plasma corticosterone concentration in wild-type animals; however, this WD-induced increase in plasma corticosterone was significantly attenuated in V1b⁻/⁻ mice. Comparable increases in neuronal activation, indicated by increased c-fos mRNA expression, and in vasopressin mRNA expression occurred in both the supraoptic nucleus and paraventricular nucleus (PVN) of wild-type and V1b⁻/⁻ mice following WD; however, the WD-induced decrease in corticotrophin-releasing hormone mRNA expression seen in the PVN of wild-type mice was not observed in the PVN of V1b⁻/⁻ mice. These data suggest that, although the vasopressin V1bR is not required for normal HNS function, it is necessary for a full HPA-axis response to the osmotic stress of WD.


Asunto(s)
Corticosterona/sangre , Deshidratación , Receptores de Vasopresinas/fisiología , Estrés Fisiológico , Hormona Adrenocorticotrópica/sangre , Animales , Hibridación in Situ , Masculino , Ratones , Ratones Noqueados , Receptores de Vasopresinas/genética
7.
J Neuroendocrinol ; 22(4): 301-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20136689

RESUMEN

The expression of the novel peptide apelin and its receptor APJ within specific regions of the brain, in particular the magnocellular neurones of the hypothalamus and the circumventricular organs, has implicated the apelinergic system in mechanisms controlling fluid homeostasis. In addition, apelin and APJ are considered to be involved in controlling arginine vasopressin (AVP) secretion into the circulation and release within the hypothalamic-neurohypophysial system. To clarify the role of APJ during regulation of fluid homeostasis, we compared the effects of osmotic stimulation on the urinary concentrating capacities and central nervous system responses of salt-loaded (SL) and water-deprived (WD) female APJ knockout (APJ(-/-)) mice and wild-type controls. SL resulted in a significantly increased urine volume in APJ(-/-) mice compared to wild-type controls, whereas WD in APJ(-/-) mice failed to reduce urine volume as seen in wild-type controls. AVP transcripts in the supraoptic and paraventricular nuclei and plasma AVP concentrations were significantly attenuated in SL APJ(-/-) mice compared to SL wild-type, but increased comparably in wild-type and APJ(-/-) mice after WD. Analysis of c-fos mRNA expression in the median preoptic nucleus and subfornical organ in response to either WD or SL showed attenuated expression in APJ(-/-) compared to wild-type mice. These findings further implicate the apelinergic system in mechanisms controlling fluid homeostasis, particularly at a neuroendocrine level, and suggest stimulus-specific involvement in vasopressinergic activity.


Asunto(s)
Sistemas Neurosecretores/fisiología , Receptores Acoplados a Proteínas G/genética , Animales , Receptores de Apelina , Líquidos Corporales/metabolismo , Líquidos Corporales/fisiología , Femenino , Regulación de la Expresión Génica , Homeostasis/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Sistemas Neurosecretores/metabolismo , Presión Osmótica/fisiología , Estimulación Física , Receptores Acoplados a Proteínas G/fisiología , Sales (Química)/farmacología , Estrés Fisiológico/fisiología , Vasopresinas/metabolismo , Privación de Agua/fisiología , Desequilibrio Hidroelectrolítico/sangre , Desequilibrio Hidroelectrolítico/fisiopatología , Desequilibrio Hidroelectrolítico/orina
8.
J Endocrinol ; 197(3): 503-15, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18492816

RESUMEN

The phytoestrogens genistein, daidzein and the daidzein metabolite equol have been shown previously to possess oestrogen agonist activity. However, following consumption of soya diets, they are found in the body not only as aglycones but also as metabolites conjugated at their 4'- and 7-hydroxyl groups with sulphate. This paper describes the effects of monosulphation on the oestrogen agonist properties of these three phytoestrogens in MCF-7 human breast cancer cells in terms of their relative ability to compete with [(3)H]oestradiol for binding to oestrogen receptor (ER), to induce a stably transfected oestrogen-responsive reporter gene (ERE-CAT) and to stimulate cell growth. In no case did sulphation abolish activity. The 4'-sulphation of genistein reduced oestrogen agonist activity to a small extent in whole-cell assays but increased the relative binding affinity to ER. The 7-sulphation of genistein, and also of equol, reduced oestrogen agonist activity substantially in all assays. By contrast, the position of monosulphation of daidzein acted in an opposing manner on oestrogen agonist activity. Sulphation at the 4'-position of daidzein resulted in a modest reduction in oestrogen agonist activity but sulphation of daidzein at the 7-position resulted in an increase in oestrogen agonist activity. Molecular modelling and docking studies suggested that the inverse effects of sulphation could be explained by the binding of daidzein into the ligand-binding domain of the ER in the opposite orientation compared with genistein and equol. This is the first report of sulphation enhancing activity of an isoflavone and inverse effects of sulphation between individual phytoestrogens.


Asunto(s)
Genisteína/farmacología , Isoflavonas/farmacología , Fitoestrógenos/farmacología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Equol , Estradiol/metabolismo , Estradiol/farmacología , Receptor alfa de Estrógeno/metabolismo , Femenino , Genisteína/metabolismo , Humanos , Isoflavonas/metabolismo , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Sulfatos/metabolismo
10.
Surg Innov ; 13(4): 265-73, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17227925

RESUMEN

Bariatric surgery is the most effective treatment for achieving sustained weight loss in morbidly obese patients. Although the use of gastric bypass is growing rapidly, the potential life expectancy benefits of the procedure are unknown. We created a Markov decision analysis model to examine the effect of gastric bypass surgery on life expectancy in morbidly obese patients (body mass index [BMI] = 40 kg/m2). Input assumptions for the model were obtained from published life tables (baseline mortality risks), epidemiologic studies (obesity-related excess mortality), and large case series (surgical outcomes). In our baseline analysis, a 40-year-old woman (BMI = 40 kg/m2) would gain 2.6 years of life expectancy by undergoing gastric bypass (38.7 years versus 36.2 years without surgery). In sensitivity analysis, life-years gained with surgery remained substantial when assumptions were varied across reasonable ranges for surgical mortality risk (1.0-3.0 years) and effectiveness (0.9-4.4 years). Life-years gained with gastric bypass surgery did not vary considerably by age and sex subgroups. Relative to other major surgical procedures, gastric bypass for morbid obesity is associated with substantial gains in life expectancy. Long- term data from prospective studies are needed to confirm this finding.


Asunto(s)
Técnicas de Apoyo para la Decisión , Derivación Gástrica , Esperanza de Vida , Cadenas de Markov , Obesidad Mórbida/mortalidad , Obesidad Mórbida/cirugía , Adulto , Índice de Masa Corporal , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Pérdida de Peso
11.
Neurology ; 65(8): 1268-77, 2005 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-16247056

RESUMEN

BACKGROUND: Abnormal cortical pain responses in patients with fibromyalgia and conversion disorder raise the possibility of a neurobiologic basis underlying so-called "functional" chronic pain. OBJECTIVE: To use percept-related fMRI to test the hypothesis that patients with a painful functional bowel disorder do not process visceral input or sensations normally or effectively at the cortical level. METHODS: Eleven healthy subjects and nine patients with irritable bowel syndrome (IBS) underwent fMRI during rectal distensions that elicited either a moderate level of urge to defecate or pain. Subjects continuously rated their rectal stimulus-evoked urge or pain sensations during fMRI acquisition. fMRI data were interrogated for activity related to stimulus presence and to specific sensations. RESULTS: In IBS, abnormal responses associated with rectal-evoked sensations were identified in five brain regions. In primary sensory cortex, there were urge-related responses in the IBS but not control group. In the medial thalamus and hippocampus, there were pain-related responses in the IBS but not control group. However, pronounced urge- and pain-related activations were present in the right anterior insula and the right anterior cingulate cortex in the control group but not the IBS group. CONCLUSIONS: Percept-related fMRI revealed abnormal urge- and pain-related forebrain activity during rectal distension in patients with irritable bowel syndrome (IBS). As visceral stimulation evokes pain and triggers unconscious processes related to homeostasis and reflexes, abnormal brain responses in IBS may reflect the sensory symptoms of rectal pain and hypersensitivity, visceromotor dysfunction, and abnormal interoceptive processing.


Asunto(s)
Síndrome del Colon Irritable/diagnóstico , Síndrome del Colon Irritable/fisiopatología , Dolor Intratable/diagnóstico , Dolor Intratable/fisiopatología , Prosencéfalo/fisiopatología , Aferentes Viscerales/fisiopatología , Adulto , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Corteza Cerebral/fisiopatología , Colon/inervación , Colon/fisiopatología , Femenino , Lateralidad Funcional/fisiología , Humanos , Síndrome del Colon Irritable/psicología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Umbral del Dolor/fisiología , Dolor Intratable/psicología , Estimulación Física , Prosencéfalo/anatomía & histología , Trastornos Psicofisiológicos/diagnóstico , Trastornos Psicofisiológicos/etiología , Trastornos Psicofisiológicos/fisiopatología , Recto/inervación , Recto/fisiopatología , Estrés Psicológico/diagnóstico , Estrés Psicológico/etiología , Estrés Psicológico/fisiopatología , Tálamo/anatomía & histología , Tálamo/fisiopatología , Aferentes Viscerales/anatomía & histología
12.
J Appl Toxicol ; 25(4): 301-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16021681

RESUMEN

This paper addresses the question of whether p-hydroxybenzoic acid, the common metabolite of parabens, possesses oestrogenic activity in human breast cancer cell lines. The alkyl esters of p-hydroxybenzoic acid (parabens) are used widely as preservatives in consumer products to which the human population is exposed and have been shown previously to possess oestrogenic activity and to be present in human breast tumour tissue, which is an oestrogen-responsive tissue. Recent work has shown p-hydroxybenzoic acid to give an oestrogenic response in the rodent uterotrophic assay. We report here that p-hydroxybenzoic acid possesses oestrogenic activity in a panel of assays in human breast cancer cell lines. p-Hydroxybenzoic acid was able to displace [(3)H]oestradiol from cytosolic oestrogen receptor of MCF7 human breast cancer cells by 54% at 5 x 10(6)-fold molar excess and by 99% at 10(7)-fold molar excess. It was able to increase the expression of a stably integrated oestrogen responsive reporter gene (ERE-CAT) at a concentration of 5 x 10(-4) M in MCF7 cells after 24 h and 7 days, which could be inhibited by the anti-oestrogen ICI 182 780 (Faslodex, fulvestrant). Proliferation of two human breast cancer cell lines (MCF7, ZR-75-1) could be increased by 10(-5) M p-hydroxybenzoic acid. Following on from previous studies showing a decrease in oestrogenic activity of parabens with shortening of the linear alkyl chain length, this study has compared the oestrogenic activity of p-hydroxybenzoic acid where the alkyl grouping is no longer present with methylparaben, which has the shortest alkyl group. Intrinsic oestrogenic activity of p-hydroxybenzoic acid was similar to that of methylparaben in terms of relative binding to the oestrogen receptor but its oestrogenic activity on gene expression and cell proliferation was lower than that of methylparaben. It can be concluded that removal of the ester group from parabens does not abrogate its oestrogenic activity and that p-hydroxybenzoic acid can give oestrogenic responses in human breast cancer cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Estrógenos no Esteroides/farmacología , Estrógenos/biosíntesis , Parabenos/farmacología , Unión Competitiva/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Estradiol/análogos & derivados , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Femenino , Fulvestrant , Genes Reporteros/genética , Humanos
13.
J Steroid Biochem Mol Biol ; 94(5): 431-43, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15876408

RESUMEN

Previous studies have compared the oestrogenic properties of phytoestrogens in a wide variety of disparate assays. Since not all phytoestrogens have been tested in each assay, this makes inter-study comparisons and ranking oestrogenic potency difficult. In this report, we have compared the oestrogen agonist and antagonist activity of eight phytoestrogens (genistein, daidzein, equol, miroestrol, deoxymiroestrol, 8-prenylnaringenin, coumestrol and resveratrol) in a range of assays all based within the same receptor and cellular context of the MCF7 human breast cancer cell line. The relative binding of each phytoestrogen to oestrogen receptor (ER) of MCF7 cytosol was calculated from the molar excess needed for 50% inhibition of 3H]oestradiol binding (IC50), and was in the order coumestrol (35x)/8-prenylnaringenin (45x)/deoxymiroestrol (50x)>miroestrol (260x)>genistein (1000x)>equol (4000x)>daidzein (not achieved: 40% inhibition at 10(4)-fold molar excess)>resveratrol (not achieved: 10% inhibition at 10(5)-fold molar excess). For cell-based assays, the rank order of potency (estimated in terms of the concentration needed to achieve a response equivalent to 50% of that found with 17beta-oestradiol (IC50)) remained very similar for all the assays whether measuring ligand ability to induce a stably transfected oestrogen-responsive ERE-CAT reporter gene, cell growth in terms of proliferation rate after 7 days or cell growth in terms of saturation density after 14 days. The IC50 values for these three assays in order were for 17beta-oestradiol (1 x 10(-11)M, 1 x 10(-11)M, 2 x 10(-11)M), and in rank order of potency for the phytoestrogens, deoxymiroestrol (1 x 10(-10)M, 3 x 10(-11)M, 2 x 10(-11)M)>miroestrol (3 x 10(-10)M, 2 x 10(-10)M, 8 x 10(-11)M)>8-prenylnaringenin (1 x 10(-9)M, 3 x 10(-10)M, 3 x 10(-10)M)>coumestrol (3 x 10(-8)M, 2 x 10(-8)M, 3 x 10(-8)M)>genistein (4 x 10(-8)M, 2 x 10(-8)M, 1 x 10(-8)M)/equol (1 x 10(-7)M, 3 x 10(-8)M, 2 x 10(-8)M)>daidzein (3 x 10(-7)M, 2 x 10(-7)M, 4 x 10(-8)M)>resveratrol (4 x 10(-6)M, not achieved, not achieved). Despite using the same receptor context of the MCF7 cells, this rank order differed from that determined from receptor binding. The most marked difference was for coumestrol and 8-prenylnaringenin which both displayed a relatively potent ability to displace [3H]oestradiol from cytosolic ER compared with their much lower activity in the cell-based assays. Albeit at varying concentrations, seven of the eight phytoestrogens (all except resveratrol) gave similar maximal responses to that given by 17beta-oestradiol in cell-based assays which makes them full oestrogen agonists. We found no evidence for any oestrogen antagonist action of any of these phytoestrogens at concentrations of up to 10(-6)M on either reporter gene induction or on stimulation of cell growth.


Asunto(s)
Neoplasias de la Mama/metabolismo , Moduladores de los Receptores de Estrógeno/farmacología , Fitoestrógenos/farmacología , Receptores de Estrógenos/agonistas , Receptores de Estrógenos/antagonistas & inhibidores , Bioensayo , Proliferación Celular , Antagonistas de Estrógenos/farmacología , Femenino , Expresión Génica/efectos de los fármacos , Genes Reporteros , Humanos , Ligandos , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Células Tumorales Cultivadas
14.
Surg Endosc ; 19(5): 616-20, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15759185

RESUMEN

BACKGROUND: Because of the growing interest in surgery to treat morbid obesity, this study examined changes in the utilization and in-hospital outcomes of bariatric surgery in the United States over a 10-year period. METHODS: Data were obtained from the Nationwide Inpatient Sample, the largest all-payer discharge database in the United States. International Classification of Disease (ICD-9) codes were used to identify all bariatric procedures performed for adults from 1990 to 2000. Population-based rates of surgery for each year were calculated by applying sampling weights and U.S. Census data. Secular trends in annual rates of surgery, changes in patient characteristics, and in-hospital mortality and complications were analyzed. RESULTS: From 1990 to 2000, the national annual rate of bariatric surgery increased nearly six fold, from 2.4 to 14.1 per 100,000 adults (p = 0.001). There has been more than a ninefold increase in the use of gastric bypass procedures (1.4 to 13.1 per 100,000; p < 0.001). This represents an increase from 55% of all bariatric procedures in 1990 to 93% of such procedures in 2000 (p < 0.001). The rates of in-hospital mortality were low (0.4% overall), but increased slightly over time (0.2% in 1990 to 0.5% in 2000; p = 0.009). There is no significant difference in adjusted mortality for the past 8 years, but a slight rise did occur over the full 10-year period. The rates for reoperation (1.3%) and pulmonary emboli (0.3%) remained stable. The rates for respiratory failure associated with bariatric surgery declined from 7.7% in 1990 to 4.5% in 2000 (p < 0.001). Over this time, the mean length of hospital stay declined from 6.0 to 4.1 days (p < 0.001). CONCLUSIONS: The annual rate of bariatric surgery in the United States increased nearly six fold between 1990 and 2000, with little change in in-hospital morbidity and mortality. This appears to be driven largely by the increasing popularity of gastric bypass procedures.


Asunto(s)
Cirugía Bariátrica/tendencias , Adulto , Cirugía Bariátrica/mortalidad , Cirugía Bariátrica/estadística & datos numéricos , Comorbilidad , Bases de Datos Factuales , Femenino , Derivación Gástrica/estadística & datos numéricos , Gastroplastia/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/cirugía , Alta del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Embolia Pulmonar/epidemiología , Embolia Pulmonar/etiología , Reoperación/estadística & datos numéricos , Resultado del Tratamiento , Estados Unidos/epidemiología
15.
J Neurophysiol ; 92(2): 1248-51, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15277602

RESUMEN

Paradoxical heat (PH), the illusion of skin heat, accompanies many neurological disorders. Using the technique of percept-related functional MRI, we found a region of the right insular cortex specifically activated when subjects perceive a heat sensation in their right hand even though their skin temperature is cool or at neutral. This region was suppressed during mild skin cooling. We propose that this differential response is a manifestation of the role of the insula in signaling temperature perceptions regardless of the actual temperature of the skin. These findings suggest that a region within the insula has a complex role in heat perception, perhaps contributing to a specific, rather than general, thermosensory perception. These data provide insight to our basic understanding of normal and pathological thermosensory perceptions.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/fisiología , Calor , Ilusiones/fisiología , Imagen por Resonancia Magnética , Sensación Térmica/fisiología , Adulto , Femenino , Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Sensación/fisiología , Temperatura Cutánea
16.
J Appl Toxicol ; 24(1): 5-13, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14745841

RESUMEN

Parabens are used as preservatives in many thousands of cosmetic, food and pharmaceutical products to which the human population is exposed. Although recent reports of the oestrogenic properties of parabens have challenged current concepts of their toxicity in these consumer products, the question remains as to whether any of the parabens can accumulate intact in the body from the long-term, low-dose levels to which humans are exposed. Initial studies reported here show that parabens can be extracted from human breast tissue and detected by thin-layer chromatography. More detailed studies enabled identification and measurement of mean concentrations of individual parabens in samples of 20 human breast tumours by high-pressure liquid chromatography followed by tandem mass spectrometry. The mean concentration of parabens in these 20 human breast tumours was found to be 20.6 +/- 4.2 ng x g(-1) tissue. Comparison of individual parabens showed that methylparaben was present at the highest level (with a mean value of 12.8 +/- 2.2 ng x g(-1) tissue) and represents 62% of the total paraben recovered in the extractions. These studies demonstrate that parabens can be found intact in the human breast and this should open the way technically for more detailed information to be obtained on body burdens of parabens and in particular whether body burdens are different in cancer from those in normal tissues.


Asunto(s)
Neoplasias de la Mama/metabolismo , Conservantes de Alimentos/metabolismo , Parabenos/metabolismo , Conservadores Farmacéuticos/metabolismo , Neoplasias de la Mama/química , Neoplasias de la Mama/etiología , Cromatografía en Capa Delgada , Exposición a Riesgos Ambientales/efectos adversos , Estrógenos no Esteroides/efectos adversos , Femenino , Conservantes de Alimentos/análisis , Humanos , Parabenos/análisis , Parabenos/clasificación , Conservadores Farmacéuticos/análisis , Espectrometría de Masa por Ionización de Electrospray
17.
J Appl Toxicol ; 23(1): 43-51, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12518336

RESUMEN

Previous work has demonstrated that the alkyl esters of p-hydroxybenzoic acid (parabens) possess oestrogenic activity, which increases with length of alkyl chain from methylparaben to n-butylparaben and with branching in the alkyl chain from n-butylparaben to isobutylparaben. This study reports on the oestrogenic activity of benzylparaben in a variety of assays in vitro and in vivo. Benzylparaben was able to displace [(3)H]oestradiol from cytosolic oestrogen receptor (ER) of MCF7 human breast cancer cells by 22% at 1000-fold molar excess, by 40% at 10,000-fold molar excess, by 57% at 100 000-fold molar excess and by 100% at 1,000,000-fold molar excess. It was able to increase expression of a stably transfected oestrogen responsive reporter gene (ERE-CAT) in MCF7 cells after 24 h at 10(-5)M/10(-4)M and after 7 days at 10(-6)M/10(-5)M/10(-4)M. Proliferation of MCF7 cells could be increased by 10(-6)M/10(-5)M benzylparaben and this could be inhibited by 10(-7)M pure anti-oestrogen ICI 182,780, indicating that growth effects were ER mediated. Further evidence for ER-mediation was provided from the ability of benzylparaben to increase the growth of a second oestrogen-dependent human breast cancer cell line ZR-75-1, but not the oestrogen-insensitive MDA-MB-231 cell line. When tested in the presence of 10(-10)M 17beta-oestradiol, benzylparaben gave no antagonist response on the growth of either MCF7 or ZR-75-1 cells. Finally, benzylparaben could increase uterine weight in the immature mouse following topical application of three daily doses of 33 mg to dorsal skin. These results demonstrate that the oestrogenicity of methylparaben can be increased by the addition of an aryl group as well as by lengthening or branching the alkyl grouping.


Asunto(s)
Estradiol/análogos & derivados , Moduladores de los Receptores de Estrógeno/farmacología , Estrógenos no Esteroides/farmacología , Parabenos/farmacología , Administración Tópica , Animales , Unión Competitiva , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , División Celular/efectos de los fármacos , Citosol/efectos de los fármacos , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Estradiol/metabolismo , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Estrógenos no Esteroides/administración & dosificación , Femenino , Fulvestrant , Expresión Génica , Genes Reporteros , Humanos , Ratones , Ratones Endogámicos , Tamaño de los Órganos/efectos de los fármacos , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Transfección , Células Tumorales Cultivadas , Útero/efectos de los fármacos , Útero/patología
18.
Nat Neurosci ; 5(11): 1121-2, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12368810

RESUMEN

The painful sensations produced by a laceration, freeze, burn, muscle strain or internal injury are readily distinguishable because each is characterized by a particular sensory quality such as sharp, aching, burning or prickling. We propose that there are specific neural correlates of each pain quality, and here we used a new functional magnetic resonance imaging (fMRI) method to identify time-locked responses to prickle sensations that were evoked by noxious cold stimuli. With percept-related fMRI, we identified prickle-related brain activations in the anterior cingulate cortex (ACC), insula, secondary somatosensory cortex (S2), prefrontal cortex (PFC), premotor cortex (PMC), caudate nucleus and dorsomedial thalamus, indicating that multiple pain, sensory and motor areas act together to produce the prickle sensation.


Asunto(s)
Encéfalo/fisiología , Imagen por Resonancia Magnética , Dolor/fisiopatología , Sensación/fisiología , Frío , Humanos , Tacto/fisiología
19.
J Appl Toxicol ; 22(4): 219-26, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12210538

RESUMEN

The alkyl esters of p-hydroxybenzoic acid (parabens) are used widely as preservatives in foods, pharmaceuticals and cosmetics to which the human population is exposed. Recent studies have reported that methylparaben, ethylparaben, n-propylparaben and n-butylparaben all possess oestrogenic activity in several in vitro assays and in animal models in vivo. This study reports on the oestrogenic activity of isobutylparaben in a panel of assays in vitro and in vivo. Isobutylparaben was able to displace [(3)H]oestradiol from cytosolic oestrogen receptor alpha of MCF7 human breast cancer cells by 81% at 100 000-fold molar excess. Using a clonal line of MCF7 cells containing a stably transfected oestrogen-responsive ERE-CAT reporter gene, CAT gene expression could be increased by isobutylparaben such that the magnitude of the response was the same at 10(-5) M isobutylparaben as with 10(-8) M 17beta-oestradiol. Isobutylparaben could also increase expression of the endogenous oestrogen-responsive pS2 gene in MCF7 cells and maximal expression at 10(-5) M isobutylparaben could be inhibited with the anti-oestrogen ICI 182 780. The proliferation of two oestrogen-dependent human breast cancer cell lines MCF7 and ZR-75-1 could be increased with isobutylparaben such that at concentrations of 10(-5) M the proliferation response was of the same magnitude as with 10(-8) M 17beta-oestradiol. Evidence for oestrogen receptor mediation of proliferation effects was provided by the inability of isobutylparaben to influence the growth of oestrogen-unresponsive MDA-MB-231 human breast cancer cells and by the ability of the anti-oestrogen ICI 182 780 to inhibit the isobutylparaben effects on MCF7 cell growth. The proliferation response to 10(-10) M 17beta-oestradiol was not antagonized with isobutylparaben at any concentration from 10(-9) M to 10(-4) M in either MCF7 or ZR-75-1 cells. Finally, subcutaneous administration of isobutylparaben was able to increase the uterine weight in the immature mouse after three daily doses of 1.2 or 12.0 mg per mouse. Previous work using linear-alkyl-chain parabens has shown that oestrogenic activity increases with alkyl chain length from methylparaben to n-butylparaben. The results here show that branching of the alkyl chain to isobutylparaben increases oestrogenic activity beyond that of the equivalent length linear alkyl chain in n-butylparaben.


Asunto(s)
Estradiol/análogos & derivados , Moduladores de los Receptores de Estrógeno , Estrógenos no Esteroides/toxicidad , Parabenos/toxicidad , Animales , Neoplasias de la Mama/metabolismo , División Celular , Relación Dosis-Respuesta a Droga , Estradiol/farmacología , Receptor alfa de Estrógeno , Estrógenos no Esteroides/antagonistas & inhibidores , Femenino , Fulvestrant , Regulación Neoplásica de la Expresión Génica , Humanos , Ligandos , Ratones , Ratones Endogámicos , Tamaño de los Órganos/efectos de los fármacos , Unión Proteica , Proteínas/genética , ARN Mensajero/genética , Receptores de Estrógenos/metabolismo , Factor Trefoil-1 , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor , Útero/efectos de los fármacos , Útero/patología
20.
Tob Control ; 11 Suppl 2: ii38-42, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12034980

RESUMEN

OBJECTIVE: To determine if restaurant business declines or improves after the implementation of restrictive restaurant smoking policies. DESIGN: Analysis used a pre/post-quasi-experimental design that compared town meals tax receipts before and after the imposition of highly restrictive restaurant smoking policies in adopting versus non-adopting communities. The effect of restaurant smoking policies was estimated using a fixed effects regression model, entering a panel of 84 months of data for the 239 towns in the study. A separate model estimated the effect of restaurant smoking policies on establishments that served alcohol. MAIN OUTCOME MEASURE: Change in the trend in meals tax revenue (adjusted for population) following the implementation of highly restrictive restaurant smoking policies. RESULTS: The local adoption of restrictive restaurant smoking policies did not lead to a measurable deviation from the strong positive trend in revenue between 1992 and 1998 that restaurants in Massachusetts experienced. Controlling for other less restrictive restaurant smoking policies did not change this finding. Similar results were found for only those establishments that served alcoholic beverages. CONCLUSIONS: Highly restrictive restaurant smoking policies do not have a significant effect on a community's level of meal receipts, indicating that claims of community wide restaurant business decline under such policies are unwarranted.


Asunto(s)
Restaurantes/economía , Prevención del Hábito de Fumar , Fumar/economía , Economía , Humanos , Massachusetts/epidemiología , Política Pública , Restaurantes/estadística & datos numéricos , Fumar/epidemiología
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