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1.
Diabet Med ; 36(1): 44-51, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30102801

RESUMEN

AIM: Recent studies have reported an association between low vitamin D levels and diabetic peripheral neuropathy. However, many of these did not differentiate between people with painful diabetic peripheral neuropathy and those with painless diabetic peripheral neuropathy, or assess major confounding factors including sunlight exposure and daily activity. Our study addressed these limitations and evaluated vitamin D levels in people with carefully phenotyped diabetic peripheral neuropathy and controls. METHODS: Forty-five white Europeans with Type 2 diabetes and 14 healthy volunteers underwent clinical and neurophysiological assessments. People with Type 2 diabetes were then divided into three groups (17 with painful diabetic peripheral neuropathy, 14 with painless diabetic peripheral neuropathy and 14 with no diabetic peripheral neuropathy). All had seasonal sunlight exposure and daily activity measured, underwent a lower limb skin biopsy and had 25-hydroxyvitamin D measured during the summer months, July to September. RESULTS: After adjusting for age, BMI, activity score and sunlight exposure, 25-hydroxyvitamin D levels (nmol/l) (se) were significantly lower in people with painful diabetic peripheral neuropathy [painful diabetic peripheral neuropathy 34.9 (5.8), healthy volunteers 62.05 (6.7), no diabetic peripheral neuropathy 49.6 (6.1), painless diabetic peripheral neuropathy 53.1 (6.2); ANCOVAP = 0.03]. Direct logistic regression was used to assess the impact of seven independent variables on painful diabetic peripheral neuropathy. Vitamin D was the only independent variable to make a statistically significant contribution to the model with an inverted odds ratio of 1.11. Lower 25-hydroxyvitamin D levels also correlated with lower cold detection thresholds (r = 0.39, P = 0.02) and subepidermal nerve fibre densities (r = 0.42, P = 0.01). CONCLUSIONS: We have demonstrated a significant difference in 25-hydroxyvitamin D levels in well-characterized people with painful diabetic peripheral neuropathy, while accounting for the main confounding factors. This suggests a possible role for vitamin D in the pathogenesis of painful diabetic peripheral neuropathy. Further prospective and intervention trials are required to prove causality between low vitamin D levels and painful diabetic peripheral neuropathy.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/sangre , Neuropatías Diabéticas/etiología , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/complicaciones , Vitamina D/análogos & derivados , Anciano , Estudios Transversales , Diabetes Mellitus Tipo 2/fisiopatología , Neuropatías Diabéticas/fisiopatología , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Oportunidad Relativa , Factores de Riesgo , Vitamina D/sangre , Deficiencia de Vitamina D/fisiopatología , Población Blanca
2.
Ultrasound Obstet Gynecol ; 54(1): 35-50, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30737852

RESUMEN

Cardiac output (CO), along with blood pressure and vascular resistance, is one of the most important parameters of maternal hemodynamic function. Substantial changes in CO occur in normal pregnancy and in most obstetric complications. With the development of several non-invasive techniques for the measurement of CO, there is a growing interest in the determination of this parameter in pregnancy. These techniques were initially developed for use in critical-care settings and were subsequently adopted in obstetrics, often without appropriate validation for use in pregnancy. In this article, methods and devices for the measurement of CO are described and compared, and recommendations are formulated for their use in pregnancy, with the aim of standardizing the assessment of CO and peripheral vascular resistance in clinical practice and research studies on maternal hemodynamics. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Gasto Cardíaco/fisiología , Ecocardiografía/métodos , Hemodinámica/fisiología , Resistencia Vascular/fisiología , Adulto , Presión Sanguínea/fisiología , Cateterismo de Swan-Ganz/métodos , Femenino , Corazón/diagnóstico por imagen , Corazón/fisiología , Humanos , Hipertensión Inducida en el Embarazo/fisiopatología , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Embarazo , Mujeres Embarazadas , Análisis de la Onda del Pulso/métodos , Ultrasonografía Doppler/métodos
3.
Hum Reprod ; 32(5): 985-992, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28333321

RESUMEN

STUDY QUESTION: Are there differences in preconception cardiovascular function between women who have a viable pregnancy and those who have a first trimester miscarriage? SUMMARY ANSWER: Preconception cardiovascular function of central haemodynamics and arterial function are similar between women who have a viable pregnancy and those who have a first trimester miscarriage. WHAT IS KNOWN ALREADY: Miscarriages have been associated with increased long-term cardiovascular disease risk, and arterial and cardiovascular dysfunction has been hypothesised as the common link. It is not known if these risks are present prior to pregnancy or are a reflection of poor arterial and haemodynamic adaptation to pregnancy. STUDY DESIGN, SIZE, DURATION: This prospective longitudinal preconception cohort study was conducted over 18 months. In total, 367 participants were recruited pre-pregnancy, from which 197 pregnancies were recorded; 39 of these pregnancies ended in first trimester miscarriage. Complete longitudinal data were available for 172 pregnancies (140 viable pregnancies, 32 first trimester miscarriages) from pre-pregnancy to 6 weeks gestation. PARTICIPANTS/MATERIALS, SETTING, METHODS: This was a single site study based at a maternity hospital in London. Healthy women were recruited prior to natural conception and followed up once they became pregnant. All underwent haemodynamic [cardiac output (CO), peripheral vascular resistance (PVR)] and arterial function [aortic augmentation index (AIx) and pulse wave velocity (PWV)] testing prior to pregnancy and at 6 weeks gestation, using non-invasive devices (gas re-breathing method, Innocor® and an occilometric device, Vicorder®). Cross-sectional measurements at pre-pregnancy and 6 weeks gestation and a longitudinal analysis of changes were compared between women who had a subsequent viable pregnancy, and those who had a subsequent first trimester miscarriage. MAIN RESULTS AND THE ROLE OF CHANCE: There were no differences between women destined to have a healthy ongoing pregnancy compared to those who miscarried, in terms of baseline cardiovascular function, assessed by CO, PVR, PWV or AIx. Similarly, between the groups, there were no differences in pregnancy adaptation with similar trends in cardiovascular function changes from pre-pregnancy to 6 weeks gestation. LIMITATIONS, REASONS FOR CAUTION: Whilst this is the first study to investigate preconception and early pregnancy haemodynamic and arterial function in relation to viability, the relatively modest number of miscarriages may not be sufficient to show subtle differences in haemodynamic changes if these were present. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that pre-pregnancy haemodynamic and arterial function is unlikely to be the causal link between miscarriages and future cardiovascular disease. Our findings suggests that factors other than the presence of a viable embryo drive cardiovascular changes in early pregnancy. This study raises new questions about miscarriages as an independent risk event which predisposes women to increased cardiovascular risk later in life. STUDY FUNDING/COMPETING INTEREST(S): The investigators are funded by NIHR Imperial BRC, NIHR Cambridge BRC, Action Medical Research, Imperial College Healthcare Charity and Tommy's Charity. We acknowledge the loan of ultrasound equipment from Samsung Medison (South Korea)/MIS Ltd and provision of fertility monitors from SPD Development Company Ltd (Bedford, UK). There are no competing interests. C.C.L. is supported by the UK National Institute for Health Research Biomedical Research Centre based at Imperial College Healthcare National Health Service Trust and Imperial College London. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Aborto Espontáneo/fisiopatología , Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Hemodinámica/fisiología , Primer Trimestre del Embarazo , Adulto , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Embarazo , Estudios Prospectivos , Factores de Riesgo , Salud de la Mujer
4.
Ultrasound Obstet Gynecol ; 49(1): 78-84, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27859800

RESUMEN

OBJECTIVE: Birth weight (BW) is thought to be determined by maternal health and genetic, nutritional and placental factors, the latter being influenced by anatomical development and perfusion. Maternal cardiovascular changes contribute to uteroplacental perfusion; however, they have not yet been investigated in relation to fetal growth or BW. Our aim was to explore the relationship between maternal cardiovascular adaptation, fetal growth and BW in healthy pregnancies. METHODS: This was a longitudinal prospective study of women planning to conceive a pregnancy. Maternal cardiac output (CO), cardiac index (CI), pulse-wave velocity, aortic augmentation index, central blood pressure and peripheral vascular resistance were assessed prior to pregnancy and at 6, 23 and 33 weeks' gestation. Fetal growth was assessed using serial ultrasound measurements of biometry. RESULTS: In total, 143 women volunteered to participate and were eligible for study inclusion. A total of 101 women conceived within 18 months and there were 64 live births with normal pregnancy outcome. There were positive correlations between BW and the pregnancy-induced changes in CO (ρ = 0.4, P = 0.004), CI (ρ = 0.3, P = 0.02) and peripheral vascular resistance (ρ = 0.3, P = 0.02). There were significant associations between second-to-third-trimester fetal weight gain and the prepregnancy-to-second-trimester increase in CO (Δ, 0.8 ± 1.2 L/min; ρ = 0.3, P = 0.02) and CI (Δ, 0.4 ± 0.6 L/min/m2 ; ρ = 0.3, P = 0.04) and reduction in aortic augmentation index (Δ, -10 ± 9%; ρ = -0.3, P = 0.04). CONCLUSIONS: In healthy pregnancy, incremental changes in maternal CO in early pregnancy are associated with third-trimester fetal growth and BW. It is plausible that this association is causative as the changes predate third-trimester fetal growth and eventual BW. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Peso al Nacer , Gasto Cardíaco/fisiología , Desarrollo Fetal , Adulto , Presión Sanguínea , Femenino , Humanos , Estudios Longitudinales , Embarazo , Segundo Trimestre del Embarazo , Estudios Prospectivos
5.
Br J Clin Pharmacol ; 80(1): 28-44, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25655310

RESUMEN

There is increasing evidence suggesting that epoxyeicosatrienoic acids (EETs) play an important role in cardioprotective mechanisms. These include regulating vascular tone, modulating inflammatory responses, improving cardiomyocyte function and reducing ischaemic damage, resulting in attenuation of animal models of cardiovascular risk factors. This review discusses the current knowledge on the role of EETs in endothelium-dependent control of vascular tone in the healthy and in subjects with cardiovascular risk factors, and considers the pharmacological potential of targeting this pathway.


Asunto(s)
Fenómenos Fisiológicos Cardiovasculares , Ácidos Hidroxieicosatetraenoicos/fisiología , Animales , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/fisiopatología , Humanos , Ácidos Hidroxieicosatetraenoicos/biosíntesis , Ácidos Hidroxieicosatetraenoicos/genética , Terapia Molecular Dirigida
6.
Curr Hypertens Rep ; 17(5): 36, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25833457

RESUMEN

Hypertensive disorders of pregnancy affect approximately 5-10% of all maternities and are major contributors of maternal and neonatal morbidity and mortality worldwide. This group of disorders encompasses chronic hypertension, as well as conditions that arise de novo in pregnancy: gestational hypertension and pre-eclampsia. The latter group is thought to be part of the same continuum but with arbitrary division. Research into the aetiology of hypertension in pregnancy have largely been focused on pre-eclampsia, with a majority of studies exploring either pregnancy-associated factors such as placental-derived or immunologic responses to pregnancy tissue, or maternal constitutional factors such as cardiovascular health and endothelial dysfunction. The evidence base for the pathophysiology and progression of hypertensive disorders in pregnancy, particularly pre-eclampsia, is reviewed. Clinical algorithms and pharmacological agents for the management of hypertension in pregnancy are summarised, with a brief focus on post-partum considerations and long-term health implications. Novel therapeutic options for the management of pre-eclampsia are also explored.


Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión Inducida en el Embarazo/tratamiento farmacológico , Animales , Presión Sanguínea , Enfermedades Cardiovasculares/etiología , Femenino , Humanos , Placenta , Embarazo , Factores de Riesgo
7.
J Mech Behav Biomed Mater ; 141: 105752, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36893688

RESUMEN

The arterial wall's tri-layered macroscopic and layer-specific microscopic structure determine its mechanical properties, which vary at different arterial locations. Combining layer-specific mechanical data and tri-layered modelling, this study aimed to characterise functional differences between the pig ascending (AA) and lower thoracic aorta (LTA). AA and LTA segments were obtained for n=9 pigs. For each location, circumferentially and axially oriented intact wall and isolated layer strips were tested uniaxially and the layer-specific mechanical response modelled using a hyperelastic strain energy function. Then, layer-specific constitutive relations and intact wall mechanical data were combined to develop a tri-layered model of an AA and LTA cylindrical vessel, accounting for the layer-specific residual stresses. AA and LTA behaviours were then characterised for in vivo pressure ranges while stretched axially to in vivo length. The media dominated the AA response, bearing>2/3 of the circumferential load both at physiological (100 mmHg) and hypertensive pressures (160 mmHg). The LTA media bore most of the circumferential load at physiological pressure only (57±7% at 100 mmHg), while adventitia and media load bearings were comparable at 160 mmHg. Furthermore, increased axial elongation affected the media/adventitia load-bearing only at the LTA. The pig AA and LTA presented strong functional differences, likely reflecting their different roles in the circulation. The media-dominated compliant and anisotropic AA stores large amounts of elastic energy in response to both circumferential and axial deformations, which maximises diastolic recoiling function. This function is reduced at the LTA, where the adventitia shields the artery against supra-physiological circumferential and axial loads.


Asunto(s)
Adventicia , Aorta Torácica , Porcinos , Animales , Aorta Torácica/fisiología , Estrés Mecánico , Fenómenos Biomecánicos , Adventicia/fisiología
8.
J Neurol ; 270(3): 1682-1690, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36509983

RESUMEN

BACKGROUND: Magnetic resonance imaging (MRI) of the brain and cervical spinal cord is often performed in diagnostic evaluation of suspected motor neuron disease/amyotrophic lateral sclerosis (MND/ALS). Analysis of MRI-derived tissue damage metrics in a common domain facilitates group-level inferences on pathophysiology. This approach was applied to address competing hypotheses of directionality of neurodegeneration, whether anterograde, cranio-caudal dying-forward from precentral gyrus or retrograde, dying-back. METHODS: In this cross-sectional study, MRI was performed on 75 MND patients and 13 healthy controls. Precentral gyral thickness was estimated from volumetric T1-weighted images using FreeSurfer, corticospinal tract fractional anisotropy (FA) from diffusion tensor imaging using FSL, and cross-sectional cervical cord area between C1-C8 levels using Spinal Cord Toolbox. To analyse these multimodal data within a common domain, individual parameter estimates representing tissue damage at each corticospinal tract level were first converted to z-scores, referenced to healthy control norms. Mixed-effects linear regression models were then fitted to these z-scores, with gradients hypothesised to represent directionality of neurodegeneration. RESULTS: At group-level, z-scores did not differ significantly between precentral gyral and intracranial corticospinal tract tissue damage estimates (regression coefficient - 0.24, [95% CI - 0.62, 0.14], p = 0.222), but step-changes were evident between intracranial corticospinal tract and C1 (1.14, [95% CI 0.74, 1.53], p < 0.001), and between C5 and C6 cord levels (0.98, [95% CI 0.58, 1.38], p < 0.001). DISCUSSION: Analysis of brain and cervical spinal MRI data in a common domain enabled investigation of pathophysiological hypotheses in vivo. A cranio-caudal step-change in MND patients was observed, and requires further investigation in larger cohorts.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedad de la Neurona Motora , Humanos , Estudios Transversales , Imagen de Difusión Tensora/métodos , Enfermedad de la Neurona Motora/diagnóstico por imagen , Enfermedad de la Neurona Motora/patología , Imagen por Resonancia Magnética/métodos , Esclerosis Amiotrófica Lateral/diagnóstico , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Tractos Piramidales/diagnóstico por imagen
9.
Nat Chem ; 15(10): 1408-1414, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37620544

RESUMEN

Biomolecular radiation damage is largely mediated by radicals and low-energy electrons formed by water ionization rather than by direct ionization of biomolecules. It was speculated that such an extensive, localized water ionization can be caused by ultrafast processes following excitation by core-level ionization of hydrated metal ions. In this model, ions relax via a cascade of local Auger-Meitner and, importantly, non-local charge- and energy-transfer processes involving the water environment. Here, we experimentally and theoretically show that, for solvated paradigmatic intermediate-mass Al3+ ions, electronic relaxation involves two sequential solute-solvent electron transfer-mediated decay processes. The electron transfer-mediated decay steps correspond to sequential relaxation from Al5+ to Al3+ accompanied by formation of four ionized water molecules and two low-energy electrons. Such charge multiplication and the generated highly reactive species are expected to initiate cascades of radical reactions.

10.
Acta Neurol Scand ; 126(2): 138-43, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22070551

RESUMEN

BACKGROUND: Previous work using proton MR spectroscopy ((1)H-MRS) of the cerebellum in the ataxias suggested that (1)H-MRS abnormalities and atrophy do not necessarily occur concurrently. AIMS: To investigate the spectroscopic features of different types of ataxias. METHODS: Using a clinical MR system operating at 1.5T, we performed (1)H-MRS with a single voxel placed over the right dentate nucleus in 22 patients with gluten ataxia (GA), six patients with Friedreich's ataxia (FA), six patients with spinocerebellar ataxia type 6 (SCA6) and 21 healthy volunteers. Atrophy of the vermis and hemispheres on standard MRI was rated by a neuroradiologist. Any interaction between atrophy and (1)H-MRS was analysed for the three groups of patients and controls. RESULTS: Patients with GA had significant atrophy of the vermis and hemispheres as well as abnormal (1)H-MRS. Patients with SCA6 had more severe overall atrophy of the vermis and hemispheres, but relatively preserved N-acetyl-aspartate/creatine (NAA/Cr). The FA group showed significant atrophy of only the superior vermis with normal (1)H-MRS. CONCLUSIONS: This study suggests that (1)H-MRS of the cerebellum in patients with ataxia provides information in addition to the presence of atrophy. There are significant (1)H-MRS differences amongst different types of ataxia with interesting correlations between atrophy and NAA/Cr.


Asunto(s)
Encéfalo/patología , Ataxia Cerebelosa/patología , Ataxia de Friedreich/patología , Espectroscopía de Resonancia Magnética , Ataxias Espinocerebelosas/patología , Anciano , Atrofia/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Ultrasound Obstet Gynecol ; 40(6): 630-5, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22858888

RESUMEN

OBJECTIVE: To determine the impact of ovulation and implantation timing on first-trimester crown-rump length (CRL) and the derived gestational age (GA). METHOD: One hundred and forty-three women who were trying to conceive were recruited prospectively. The timing of ovulation and implantation and the ovulation to implantation (O-I) interval were established in 101 pregnancies using home urinary tests for luteinizing hormone and human chorionic gonadotropin. In 71 ongoing pregnancies, GA determined by measurement of fetal CRL at 10-14 weeks' gestation was compared with GA based on ovulation and implantation day. First-trimester growth was determined by serial ultrasound scans at 6-7, 8-9 and 10-14 weeks. RESULTS: The median ovulation and implantation days were 16 and 27, respectively, with an O-I interval of 11 days. GA estimated from CRL at 10-14 weeks was on average 1.3 days greater than that derived from ovulation timing. CRL Z-score was inversely related to O-I interval (ρ= -0.431, P=0.0009). There was no significant relationship between CRL growth rate and the difference between observed CRL and expected CRL based on GA from last menstrual period (ρ=0.224, P=0.08). CONCLUSIONS: Early implantation leads to a larger CRL and late implantation to a smaller CRL at 10-14 weeks, independent of CRL growth rate. Implantation timing is a major determinant of fetal size at 10-14 weeks and largely explains the variation in estimates of GA in the first trimester derived from embryonic or fetal CRL.


Asunto(s)
Largo Cráneo-Cadera , Implantación del Embrión/fisiología , Desarrollo Fetal/fisiología , Ovulación/fisiología , Adulto , Femenino , Edad Gestacional , Humanos , Embarazo , Primer Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal
12.
Neuroimage ; 53(2): 611-8, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-20600971

RESUMEN

In this study, we investigated brain mechanisms for the generation of subjective experience from objective sensory inputs. Our experimental construct was subjective tranquility. Tranquility is a mental state more likely to occur in the presence of objective sensory inputs that arise from natural features in the environment. We used functional magnetic resonance imaging to examine the neural response to scenes that were visually distinct (beach images vs. freeway images) and experienced as tranquil (beach) or non-tranquil (freeway). Both sets of scenes had the same auditory component because waves breaking on a beach and vehicles moving on a freeway can produce similar auditory spectral and temporal characteristics, perceived as a constant roar. Compared with scenes experienced as non-tranquil, we found that subjectively tranquil scenes were associated with significantly greater effective connectivity between the auditory cortex and medial prefrontal cortex, a region implicated in the evaluation of mental states. Similarly enhanced connectivity was also observed between the auditory cortex and posterior cingulate gyrus, temporoparietal cortex and thalamus. These findings demonstrate that visual context can modulate connectivity of the auditory cortex with regions implicated in the generation of subjective states. Importantly, this effect arises under conditions of identical auditory input. Hence, the same sound may be associated with different percepts reflecting varying connectivity between the auditory cortex and other brain regions. This suggests that subjective experience is more closely linked to the connectivity state of the auditory cortex than to its basic sensory inputs.


Asunto(s)
Estimulación Acústica , Afecto/fisiología , Vías Nerviosas/fisiología , Percepción/fisiología , Corteza Auditiva/fisiología , Mapeo Encefálico , Imagen Eco-Planar , Ambiente , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiología , Oxígeno/sangre , Estimulación Luminosa , Corteza Prefrontal/fisiología , Tálamo/fisiología , Adulto Joven
13.
QJM ; 113(4): 258-265, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31665476

RESUMEN

BACKGROUND: Vasopressin stimulates cyst growth in autosomal dominant polycystic kidney disease (ADPKD) and is a key therapeutic target. Evaluation of high water intake as an alternative to pharmacological vasopressin blockade is supported by patients. However feasibility, safety and adherence-promoting strategies required to deliver this remain unknown. AIMS: Assess the feasibility of a definitive randomized high water intake trial in ADPKD. METHODS: In this prospective open-label randomized trial, adult ADPKD patients with eGFR ≥ 20 ml/min/1.73 m2 were randomized to prescribed high water (HW) intake targeting urine osmolality (UOsm) ≤270 mOsm/kg, or ad libitum (AW) intake (UOsm >300 mOsm/kg). Self-management strategies including home-monitoring of urine-specific gravity (USG) were employed to promote adherence. RESULTS: We enrolled 42 participants, baseline median eGFR (HW 68.4 [interquartile range (IQR) 35.9-107.2] vs. AW 75.8 [IQR 59.0-111.0 ml/min/1.73 m2, P = 0.22) and UOsm (HW 353 [IQR 190-438] vs. AW 350 [IQR 240-452] mOsm/kg, P = 0.71) were similar between groups. After 8 weeks, 67% in the HW vs. 24% in AW group achieved UOsm ≤270 mOsm/kg, P = 0.001. HW group achieved lower UOsm (194 [IQR 190-438] vs. 379 [IQR 235-503] mOsm/kg, P = 0.01) and higher urine volumes (3155 [IQR 2270-4295] vs. 1920 [IQR 1670-2960] ml/day, P = 0.02). Two cases of hyponatraemia occurred in HW group. No acute GFR effects were detected. In total 79% (519/672) of USG were submitted and 90% (468/519) were within target. Overall, 17% withdrew during the study. CONCLUSION: DRINK demonstrated successful recruitment and adherence leading to separation between treatment arms in primary outcomes. These findings suggest a definitive trial assessing the impact of high water on kidney disease progression in ADPKD is feasible.


Asunto(s)
Ingestión de Líquidos , Riñón Poliquístico Autosómico Dominante , Agua , Adulto , Estudios de Factibilidad , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/metabolismo , Riñón Poliquístico Autosómico Dominante/fisiopatología , Riñón Poliquístico Autosómico Dominante/terapia , Estudios Prospectivos , Resultado del Tratamiento , Vasopresinas/antagonistas & inhibidores , Adulto Joven
14.
Br J Surg ; 96(8): 865-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19591159

RESUMEN

BACKGROUND: The physiological disturbances leading to lymphoedema after breast cancer surgery are poorly understood. Damage to sympathetic nerves during axillary lymph node dissection (ALND), leading to increased capillary fluid filtration, was investigated as a possible contributory factor. METHODS: The integrity of the upper limb sympathetic nervous system was tested in 36 patients before, and 3 and 12 months after ALND. Forearm vascular resistance (FVR), calculated from forearm blood flow and mean systemic arterial pressure, was measured before and after exposure to lower-body negative pressure. Forearm venous compliance was measured using (99m)Tc-labelled autologous erythrocytes and radionuclide plethysmography before and after cold water immersion of the feet. RESULTS: There were clear changes in FVR and venous compliance in response to sympathetic stimulation but no differences attributable to surgery or between the nine patients who developed lymphoedema and the 27 who did not; nor were there differences between the two arms. There was a trend towards lower preoperative FVR in patients who developed lymphoedema. CONCLUSION: Lymphoedema is not the result of sympathetic nerve damage sustained during ALND. Preoperative FVR may help predict who will get lymphoedema following this surgery.


Asunto(s)
Neoplasias de la Mama/cirugía , Escisión del Ganglio Linfático/efectos adversos , Linfedema/etiología , Sistema Nervioso Simpático/lesiones , Traumatismos del Sistema Nervioso/etiología , Adulto , Anciano , Anciano de 80 o más Años , Axila , Femenino , Antebrazo/irrigación sanguínea , Humanos , Persona de Mediana Edad , Periodo Posoperatorio , Cuidados Preoperatorios , Resistencia Vascular/fisiología
15.
J Med Ethics ; 35(3): 194-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19251973

RESUMEN

BACKGROUND: We were finding volunteers for functional magnetic resonance imaging studies with abnormalities requiring referral surprisingly frequently. The bioethics surrounding the incidental findings are not straightforward and every imaging institution will encounter this situation in their normal volunteers. Yet the implications for the individuals involved may be profound. Should all participants have review of their imaging by an expert and who should be informed? METHODS: The normal volunteers that were imaged with magnetic resonance (MR) which were reviewed by a consultant neuroradiologist. All participants completed a volunteer consent form in addition to a standard departmental MR safety screening form. The volunteer screening form requires the general practitioner details to be completed and asks the participant to consider closely the possibility and implications of finding an unexpected but potentially serious abnormality before signing. RESULTS: 525 different individuals were scanned as normal volunteers, the mean age was 35-years and 330 were males. Of these 525, 46 had definite significant abnormalities (8.8%), mean age 50-years. CONCLUSION: We have found a high rate of incidental abnormalities amongst individuals participating in imaging studies at our institution. It is our current practice to inform the research study participant of the findings, counsel them and inform their primary care physician. We think that it is advisable for researchers utilising MR imaging of the brain to have access to trained neuroradiologists, a protocol in place to deal with this problem and take consent in a way that allows the participant to realise the possibility of an abnormal finding.


Asunto(s)
Encefalopatías/diagnóstico , Experimentación Humana , Hallazgos Incidentales , Imagen por Resonancia Magnética/ética , Revelación de la Verdad/ética , Adulto , Anciano , Anciano de 80 o más Años , Discusiones Bioéticas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
16.
BMC Rheumatol ; 3: 33, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31410391

RESUMEN

BACKGROUND: The objective of this study was to explore the associations between ultrasonographic and radiographic joint scores and levels of arterial CVD risk markers in patients with osteoarthritis (OA). Secondly, to compare the levels of arterial CVD risk markers between OA phenotypes and controls. METHOD: The "Musculoskeletal pain in Ullensaker" Study (MUST) invited residents of Ullensaker municipality with self-reported OA to a medical examination. OA was defined according to the American College of Rheumatology (ACR) criteria and phenotyped based on joint distribution. Joints of the hands, hips and knees were examined by ultrasonography and conventional radiography, and scored for osteosteophytes. Hands were also scored for inflammation by grey scale (GS) synovitis and power Doppler (PD) signal. Control populations were a cohort of inhabitants of Oslo (OCP), and for external validation, a UK community-based register (UKPC).Pulse pressure augmentation index (AIx) and pulse wave velocity (PWV) were measured using the Sphygmocor apparatus (Atcor®). Ankel-brachial index (ABI) was estimated in a subset of patients. In separate adjusted regression models we explored the associations between ultrasonography and radiograph joint scores and AIx, PWV and ABI. CVD risk markers were also compared between phenotypes of OA and controls in adjusted analyses. RESULTS: Three hundred and sixty six persons with OA were included (mean age (range); 63.0 (42.0-75.0)), (females (%); 264 (72)). Of these, 155 (42.3%) had isolated hand OA, 111 (30.3%) had isolated lower limb OA and 100 (27.3%) had generalized OA. 108 persons were included in the OCP and 963 persons in the UKPC; (mean age (range); OCP: 57.2 (40.4-70.4), UKPC: 63.9 (40.0-75.0), females (%); OCP: 47 (43.5), UKPC: 543 (56.4%). Hand osteophytes were associated with AIx while GS and PD scores were not related to CVD risk markers. All OA phenotypes had higher levels of AIx compared to OCP in adjusted analyses. External validation against UKPC confirmed these findings. CONCLUSIONS: Hand osteophytes might be related to higher risk of CVD. People with OA had higher augmented central pressure compared to controls.Words 330.

17.
Thorax ; 63(4): 306-11, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18024535

RESUMEN

RATIONALE: Chronic obstructive pulmonary disease (COPD) is associated with a 2-3-fold increase in the risk of ischaemic heart disease, stroke and sudden death. The mechanisms responsible for this association are not clear and appear to be independent of smoking history. OBJECTIVE: We test the hypothesis that patients with COPD have increased arterial stiffness and blood pressure in comparison with age and smoking matched controls. METHODS: In a prospective case control study, we recruited 102 patients with COPD and 103 healthy controls matched for age and smoking status. Patients were assessed by clinical history and spirometry, with arterial stiffness and blood pressure determined using radial artery applanation tonometry and sphygmomanometry. RESULTS: Patients with COPD had increased arterial stiffness compared with matched controls, with elevated augmentation pressure (17 (1) vs 14 (1) mm Hg; p = 0.005) and a reduced time to wave reflection (131 (1) vs 137 (2) ms; p = 0.004). These differences were associated with increases in both diastolic (82 (1) vs 78 (1) mm Hg; p = 0.005) and systolic blood pressure (147 (2) vs 132 (2) mm Hg; p<0.001). Serum C reactive protein concentrations were threefold higher in patients (6.1 (0.9) vs 2.3 (0.4) mg/l; p = 0.001). Data are presented as mean (SEM). CONCLUSIONS: Patients with COPD have increased arterial stiffness and blood pressure in comparison with controls matched for age and smoking status. We speculate that increased systemic inflammation and vascular dysfunction could potentially explain the excess cardiovascular morbidity and mortality associated with COPD.


Asunto(s)
Muerte Súbita Cardíaca/etiología , Isquemia Miocárdica/etiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Accidente Cerebrovascular/etiología , Estudios de Casos y Controles , Elasticidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/fisiopatología , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Pulso Arterial , Arteria Radial/fisiología , Factores de Riesgo , Accidente Cerebrovascular/fisiopatología , Resistencia Vascular/fisiología
18.
Eur J Neurol ; 15(12): e103-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19049532

RESUMEN

BACKGROUND AND PURPOSE: The demographical evolution and the technological revolution seen in the last decades, in developed countries, have dramatically changed the practice of Neurology. However, the academic curriculum in many medical schools has not been updated accordingly over many of the European Countries. The Education Committee of the European Federation of Neurological Societies (EFNS) implemented in 2000 a Task Force on pre-graduate education trying to give guidelines to adequate pre-graduate education to the present status. METHODS AND DISCUSSION: Based on the results of two questionnaires, the first sent to the delegates of the EFNS and to the delegates of the European Board of Neurology, and the second answered by the Task Force members themselves, this paper describes the Task Force recommendations aimed to improve Neurology Education in the Medical Schools. These recommendations are also discussed with the analyses of the current bibliography available.


Asunto(s)
Comités Consultivos , Curriculum/normas , Educación de Pregrado en Medicina/normas , Neurología/educación , Neurología/normas , Curriculum/tendencias , Educación de Pregrado en Medicina/tendencias , Europa (Continente) , Humanos , Comunicación Interdisciplinaria , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/epidemiología , Enfermedades del Sistema Nervioso/terapia , Neurología/tendencias , Neurociencias/educación , Neurociencias/tendencias , Facultades de Medicina/normas , Facultades de Medicina/tendencias , Encuestas y Cuestionarios
19.
Eur J Radiol ; 66(2): 268-73, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17643890

RESUMEN

PURPOSE: Objective quantification of brain structure can aid diagnosis and therapeutic monitoring in several neuropsychiatric disorders. In this study, we aimed to compare direct and indirect quantification approaches for hippocampal formation changes in patients with mild cognitive impairment and Alzheimer's disease (AD). METHODS AND MATERIALS: Twenty-one healthy volunteers (mean age: 66.2), 21 patients with mild cognitive impairment (mean age: 66.6), and 10 patients with AD (mean age: 65.1) were enrolled. All subjects underwent extensive neuropsychological testing and were imaged at 1.5T (Vision, Siemens, Germany; T1w coronal TR=4 ms, Flip=13 degrees , FOV=250 mm, Matrix=256 x 256, 128 contiguous slices, 1.8mm). Direct measurement of the hippocampal formation was performed on coronal slices using a standardized protocol, while indirect temporal horn volume (THV) was calculated using a watershed algorithm-based software package (MeVis, Germany). Manual tracing took about 30 min, semi-automated measurement less than 3 min time. RESULTS: Successful direct and indirect quantification was performed in all subjects. A significant volume difference was found between controls and AD patients (p<0.001) with both the manual and the semi-automated approach. Group analysis showed a slight but not significant decrease of hippocampal volume and increase in temporal horn volume (THV) for subjects with mild cognitive impairment compared to volunteers (p<0.07). A significant correlation (p<0.001) of direct and indirect measurement was found. CONCLUSION: The presented indirect approach for hippocampus volumetry is equivalent to the direct approach and offers the advantages of observer independency, time reduction and thus usefulness for clinical routine.


Asunto(s)
Enfermedad de Alzheimer/patología , Hipocampo/patología , Imagen por Resonancia Magnética/métodos , Anciano , Estudios de Casos y Controles , Trastornos del Conocimiento/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas
20.
J Wildl Dis ; 44(1): 8-15, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18263817

RESUMEN

During the 2001-02 and 2002-03 breeding seasons, epizootics of Klebsiella pneumoniae resulted in a dramatic increase of pup mortality in New Zealand sea lions (Phocarctos hookeri; NZSLs) on Enderby Island (Auckland Islands). To estimate the prevalence of infection in the NZSL population, a serologic test was developed using a Western blot and a polysaccharide antigen derived from a K. pneumoniae isolate from a NZSL pup. All archived serum samples collected between 1997 and 1998 and 2004 and 2005 at Sandy Bay Beach rookery, Enderby Island, were tested (314 pups and 302 adult females). Anti-Klebsiella antibodies were detected throughout this period, but overall, only 16% of NZSL pups between birth and 5 mo of age were seropositive compared with 95.7% of adults. There was no apparent change in antibody prevalence as a result of the two epizootics. A method to determine total immunoglobulin G (IgG) levels in sea lion serum also was developed to investigate passive immunoglobulin transfer to neonates and development of an acquired immune response. The IgG concentration was significantly lower in pups (median 2.1 mg/ml) than in adult females (median 80 mg/ml). Based on serologic results, it was not possible to determine whether K. pneumoniae was an endemic or a novel pathogen to the NZSL population because the test was not able to discriminate between Klebsiella species. However, this study suggested that the transfer of passive immunity to neonates was very low in the NZSL, especially for anti-Klebsiella antibodies.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Formación de Anticuerpos , Infecciones por Klebsiella/veterinaria , Klebsiella pneumoniae/inmunología , Leones Marinos/inmunología , Animales , Animales Recién Nacidos , Animales Salvajes , Western Blotting/veterinaria , Brotes de Enfermedades/veterinaria , Electroforesis en Gel de Poliacrilamida/veterinaria , Femenino , Inmunidad Materno-Adquirida , Inmunización Pasiva/veterinaria , Inmunoglobulina G/sangre , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/inmunología , Infecciones por Klebsiella/mortalidad , Klebsiella pneumoniae/patogenicidad , Masculino , Nueva Zelanda , Especificidad de la Especie
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