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1.
Nature ; 598(7881): 425-428, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34671135

RESUMEN

Models of terrestrial planet formation predict that the final stages of planetary assembly-lasting tens of millions of years beyond the dispersal of young protoplanetary disks-are dominated by planetary collisions. It is through these giant impacts that planets like the young Earth grow to their final mass and achieve long-term stable orbital configurations1. A key prediction is that these impacts produce debris. So far, the most compelling observational evidence for post-impact debris comes from the planetary system around the nearby 23-million-year-old A-type star HD 172555. This system shows large amounts of fine dust with an unusually steep size distribution and atypical dust composition, previously attributed to either a hypervelocity impact2,3 or a massive asteroid belt4. Here we report the spectrally resolved detection of a carbon monoxide gas ring co-orbiting with dusty debris around HD 172555 between about six and nine astronomical units-a region analogous to the outer terrestrial planet region of our Solar System. Taken together, the dust and carbon monoxide detections favour a giant impact between large, volatile-rich bodies. This suggests that planetary-scale collisions, analogous to the Moon-forming impact, can release large amounts of gas as well as debris, and that this gas is observable, providing a window into the composition of young planets.

2.
Int J Cancer ; 152(4): 635-644, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36279885

RESUMEN

Based on the Global Cancer Update Programme, formally known as the World Cancer Research Fund/American Institute for Cancer Research Continuous Update Project, we performed systematic reviews and meta-analyses to investigate the association of postdiagnosis body fatness, physical activity and dietary factors with breast cancer prognosis. We searched PubMed and Embase for randomised controlled trials and longitudinal observational studies from inception to 31 October 2021. We calculated summary relative risks (RRs) and 95% confidence intervals (CIs) using random-effects meta-analyses. An independent Expert Panel graded the quality of evidence according to predefined criteria. The evidence on postdiagnosis body fatness and higher all-cause mortality (RR per 5 kg/m2 in body mass index: 1.07, 95% CI: 1.05-1.10), breast cancer-specific mortality (RR: 1.10, 95% CI: 1.06-1.14) and second primary breast cancer (RR: 1.14, 95% CI: 1.04-1.26) was graded as strong (likelihood of causality: probable). The evidence for body fatness and breast cancer recurrence and other nonbreast cancer-related mortality was graded as limited (likelihood of causality: limited-suggestive). The evidence on recreational physical activity and lower risk of all-cause (RR per 10 metabolic equivalent of task-hour/week: 0.85, 95% CI: 0.78-0.92) and breast cancer-specific mortality (RR: 0.86, 95% CI: 0.77-0.96) was judged as limited-suggestive. Data on dietary factors was limited, and no conclusions could be reached except for healthy dietary patterns, isoflavone and dietary fibre intake and serum 25(OH)D concentrations that were graded with limited-suggestive evidence for lower risk of the examined outcomes. Our results encourage the development of lifestyle recommendations for breast cancer patients to avoid obesity and be physically active.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Recurrencia Local de Neoplasia , Índice de Masa Corporal , Mama , Ejercicio Físico
3.
Int J Cancer ; 152(4): 572-599, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36279884

RESUMEN

Previous evidence on postdiagnosis body fatness and mortality after breast cancer was graded as limited-suggestive. To evaluate the evidence on body mass index (BMI), waist circumference, waist-hip-ratio and weight change in relation to breast cancer prognosis, an updated systematic review was conducted. PubMed and Embase were searched for relevant studies published up to 31 October, 2021. Random-effects meta-analyses were conducted to estimate summary relative risks (RRs). The evidence was judged by an independent Expert Panel using pre-defined grading criteria. One randomized controlled trial and 225 observational studies were reviewed (220 publications). There was strong evidence (likelihood of causality: probable) that higher postdiagnosis BMI was associated with increased all-cause mortality (64 studies, 32 507 deaths), breast cancer-specific mortality (39 studies, 14 106 deaths) and second primary breast cancer (11 studies, 5248 events). The respective summary RRs and 95% confidence intervals per 5 kg/m2 BMI were 1.07 (1.05-1.10), 1.10 (1.06-1.14) and 1.14 (1.04-1.26), with high between-study heterogeneity (I2  = 56%, 60%, 66%), but generally consistent positive associations. Positive associations were also observed for waist circumference, waist-hip-ratio and all-cause and breast cancer-specific mortality. There was limited-suggestive evidence that postdiagnosis BMI was associated with higher risk of recurrence, nonbreast cancer deaths and cardiovascular deaths. The evidence for postdiagnosis (unexplained) weight or BMI change and all outcomes was graded as limited-no conclusion. The RCT showed potential beneficial effect of intentional weight loss on disease-free-survival, but more intervention trials and well-designed observational studies in diverse populations are needed to elucidate the impact of body composition and their changes on breast cancer outcomes.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Índice de Masa Corporal , Tejido Adiposo , Circunferencia de la Cintura , Relación Cintura-Cadera
4.
Int J Cancer ; 152(4): 600-615, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36279903

RESUMEN

It is important to clarify the associations between modifiable lifestyle factors such as physical activity and breast cancer prognosis to enable the development of evidence-based survivorship recommendations. We performed a systematic review and meta-analyses to summarise the evidence on the relationship between postbreast cancer diagnosis physical activity and mortality, recurrence and second primary cancers. We searched PubMed and Embase through 31st October 2021 and included 20 observational studies and three follow-up observational analyses of patients enrolled in clinical trials. In linear dose-response meta-analysis of the observational studies, each 10-unit increase in metabolic equivalent of task (MET)-h/week higher recreational physical activity was associated with 15% and 14% lower risk of all-cause (95% confidence interval [CI]: 8%-22%, studies = 12, deaths = 3670) and breast cancer-specific mortality (95% CI: 4%-23%, studies = 11, deaths = 1632), respectively. Recreational physical activity was not associated with breast cancer recurrence (HR = 0.97, 95% CI: 0.91-1.05, studies = 6, deaths = 1705). Nonlinear dose-response meta-analyses indicated 48% lower all-cause and 38% lower breast cancer-specific mortality with increasing recreational physical activity up to 20 MET-h/week, but little further reduction in risk at higher levels. Predefined subgroup analyses across strata of body mass index, hormone receptors, adjustment for confounders, number of deaths, menopause and physical activity intensities were consistent in direction and magnitude to the main analyses. Considering the methodological limitations of the included studies, the independent Expert Panel concluded 'limited-suggestive' likelihood of causality for an association between recreational physical activity and lower risk of all-cause and breast cancer-specific mortality.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/diagnóstico , Recurrencia Local de Neoplasia/epidemiología , Riesgo , Pronóstico , Estilo de Vida
5.
Int J Cancer ; 152(4): 616-634, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36279902

RESUMEN

Little is known about how diet might influence breast cancer prognosis. The current systematic reviews and meta-analyses summarise the evidence on postdiagnosis dietary factors and breast cancer outcomes from randomised controlled trials and longitudinal observational studies. PubMed and Embase were searched through 31st October 2021. Random-effects linear dose-response meta-analysis was conducted when at least three studies with sufficient information were available. The quality of the evidence was evaluated by an independent Expert Panel. We identified 108 publications. No meta-analysis was conducted for dietary patterns, vegetables, wholegrains, fish, meat, and supplements due to few studies, often with insufficient data. Meta-analysis was only possible for all-cause mortality with dairy, isoflavone, carbohydrate, dietary fibre, alcohol intake and serum 25-hydroxyvitamin D (25(OH)D), and for breast cancer-specific mortality with fruit, dairy, carbohydrate, protein, dietary fat, fibre, alcohol intake and serum 25(OH)D. The results, with few exceptions, were generally null. There was limited-suggestive evidence that predefined dietary patterns may reduce the risk of all-cause and other causes of death; that isoflavone intake reduces the risk of all-cause mortality (relative risk (RR) per 2 mg/day: 0.96, 95% confidence interval (CI): 0.92-1.02), breast cancer-specific mortality (RR for high vs low: 0.83, 95% CI: 0.64-1.07), and recurrence (RR for high vs low: 0.75, 95% CI: 0.61-0.92); that dietary fibre intake decreases all-cause mortality (RR per 10 g/day: 0.87, 95% CI: 0.80-0.94); and that serum 25(OH)D is inversely associated with all-cause and breast cancer-specific mortality (RR per 10 nmol/L: 0.93, 95% CI: 0.89-0.97 and 0.94, 95% CI: 0.90-0.99, respectively). The remaining associations were graded as limited-no conclusion.


Asunto(s)
Suplementos Dietéticos , Neoplasias , Animales , Dieta , Grasas de la Dieta , Verduras
6.
J Nutr ; 152(4): 1070-1081, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35015882

RESUMEN

BACKGROUND: Maternal nutrition influences fetal development and may permanently alter ("program") offspring body composition and metabolism, thereby influencing later risk of diabetes and cardiovascular (cardiometabolic) disease. The prevalence of cardiometabolic disease is rising rapidly in India. OBJECTIVES: To test the hypothesis that supplementing low-income Indian women with micronutrient-rich foods preconceptionally and during pregnancy has a beneficial impact on the children's body composition and cardiometabolic risk marker profiles. METHODS: Follow-up of 1255 children aged 5-10 y whose mothers took part in the Mumbai Maternal Nutrition Project [Project "SARAS"; International Standard Randomised Controlled Trial Number (ISRCTN)62811278]. Mothers were randomly assigned to receive a daily micronutrient-rich snack or a control snack of lower micronutrient content, both made from local foods, in addition to normal diet, from before pregnancy until delivery. Children's body composition was assessed using anthropometry and DXA. Their blood pressure, plasma glucose, insulin, and lipid concentrations were measured. Outcomes were compared between allocation groups with and without adjustment for confounding factors. RESULTS: Overall, 15% of children were stunted, 34% were wasted, and 3% were overweight. In the intention-to-treat analysis, there were no differences in body composition or risk markers between children in the intervention and control groups. Among children whose mothers started supplementation ≥3 mo before conception (the "per protocol" sample) the intervention increased adiposity among girls, but not boys. BMI in girls was increased relative to controls by 2% (95% CI: 1, 4; P = 0.01); fat mass index by 10% (95% CI: 3, 18; P = 0.004); and percent fat by 7% (95% CI: 1, 13; P = 0.01) unadjusted, with similar results in adjusted models. CONCLUSIONS: Overall, supplementing women with micronutrient-rich foods from before pregnancy until delivery did not alter body composition or cardiometabolic risk markers in the children. Subgroup analyses showed that, if started ≥3 mo before conception, supplementation may increase adiposity among female children.


Asunto(s)
Composición Corporal , Enfermedades Cardiovasculares , Antropometría , Composición Corporal/fisiología , Índice de Masa Corporal , Enfermedades Cardiovasculares/prevención & control , Niño , Preescolar , Femenino , Humanos , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo
7.
J Nutr ; 152(4): 1070-1081, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-36967164

RESUMEN

BACKGROUND: Maternal nutrition influences fetal development and may permanently alter ("program") offspring body composition and metabolism, thereby influencing later risk of diabetes and cardiovascular (cardiometabolic) disease. The prevalence of cardiometabolic disease is rising rapidly in India. OBJECTIVES: To test the hypothesis that supplementing low-income Indian women with micronutrient-rich foods preconceptionally and during pregnancy has a beneficial impact on the children's body composition and cardiometabolic risk marker profiles. METHODS: Follow-up of 1255 children aged 5-10 y whose mothers took part in the Mumbai Maternal Nutrition Project [Project "SARAS"; International Standard Randomised Controlled Trial Number (ISRCTN)62811278]. Mothers were randomly assigned to receive a daily micronutrient-rich snack or a control snack of lower micronutrient content, both made from local foods, in addition to normal diet, from before pregnancy until delivery. Children's body composition was assessed using anthropometry and DXA. Their blood pressure, plasma glucose, insulin, and lipid concentrations were measured. Outcomes were compared between allocation groups with and without adjustment for confounding factors. RESULTS: Overall, 15% of children were stunted, 34% were wasted, and 3% were overweight. In the intention-to-treat analysis, there were no differences in body composition or risk markers between children in the intervention and control groups. Among children whose mothers started supplementation ≥3 mo before conception (the "per protocol" sample) the intervention increased adiposity among girls, but not boys. BMI in girls was increased relative to controls by 2% (95% CI: 1, 4; P = 0.01); fat mass index by 10% (95% CI: 3, 18; P = 0.004); and percent fat by 7% (95% CI: 1, 13; P = 0.01) unadjusted, with similar results in adjusted models. CONCLUSIONS: Overall, supplementing women with micronutrient-rich foods from before pregnancy until delivery did not alter body composition or cardiometabolic risk markers in the children. Subgroup analyses showed that, if started ≥3 mo before conception, supplementation may increase adiposity among female children.


Asunto(s)
Enfermedades Cardiovasculares , Obesidad , Embarazo , Humanos , Femenino , Niño , Obesidad/epidemiología , Composición Corporal , Madres , Micronutrientes , Enfermedades Cardiovasculares/prevención & control , Índice de Masa Corporal
8.
Magn Reson Med ; 86(4): 2122-2136, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33991126

RESUMEN

PURPOSE: A DCE-MRI technique that can provide both high spatiotemporal resolution and whole-brain coverage for quantitative microvascular analysis is highly desirable but currently challenging to achieve. In this study, we sought to develop and validate a novel dual-temporal resolution (DTR) DCE-MRI-based methodology for deriving accurate, whole-brain high-spatial resolution microvascular parameters. METHODS: Dual injection DTR DCE-MRI was performed and composite high-temporal and high-spatial resolution tissue gadolinium-based-contrast agent (GBCA) concentration curves were constructed. The high-temporal but low-spatial resolution first-pass GBCA concentration curves were then reconstructed pixel-by-pixel to higher spatial resolution using a process we call LEGATOS. The accuracy of kinetic parameters (Ktrans , vp , and ve ) derived using LEGATOS was evaluated through simulations and in vivo studies in 17 patients with vestibular schwannoma (VS) and 13 patients with glioblastoma (GBM). Tissue from 15 tumors (VS) was examined with markers for microvessels (CD31) and cell density (hematoxylin and eosin [H&E]). RESULTS: LEGATOS derived parameter maps offered superior spatial resolution and improved parameter accuracy compared to the use of high-temporal resolution data alone, provided superior discrimination of plasma volume and vascular leakage effects compared to other high-spatial resolution approaches, and correlated with tissue markers of vascularity (P ≤ 0.003) and cell density (P ≤ 0.006). CONCLUSION: The LEGATOS method can be used to generate accurate, high-spatial resolution microvascular parameter estimates from DCE-MRI.


Asunto(s)
Medios de Contraste , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Humanos
9.
BMC Cancer ; 21(1): 354, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33794823

RESUMEN

BACKGROUND: Patients with metastatic colorectal cancer are treated with cytotoxic chemotherapy supplemented by molecularly targeted therapies. There is a critical need to define biomarkers that can optimise the use of these therapies to maximise efficacy and avoid unnecessary toxicity. However, it is important to first define the changes in potential biomarkers following cytotoxic chemotherapy alone. This study reports the impact of standard cytotoxic chemotherapy across a range of circulating and imaging biomarkers. METHODS: A single-centre, prospective, biomarker-driven study. Eligible patients included those diagnosed with colorectal cancer with liver metastases that were planned to receive first line oxaliplatin plus 5-fluorouracil or capecitabine. Patients underwent paired blood sampling and magnetic resonance imaging (MRI), and biomarkers were associated with progression-free survival (PFS) and overall survival (OS). RESULTS: Twenty patients were recruited to the study. Data showed that chemotherapy significantly reduced the number of circulating tumour cells as well as the circulating concentrations of Ang1, Ang2, VEGF-A, VEGF-C and VEGF-D from pre-treatment to cycle 2 day 2. The changes in circulating concentrations were not associated with PFS or OS. On average, the MRI perfusion/permeability parameter, Ktrans, increased in response to cytotoxic chemotherapy from pre-treatment to cycle 2 day 2 and this increase was associated with worse OS (HR 1.099, 95%CI 1.01-1.20, p = 0.025). CONCLUSIONS: In patients diagnosed with colorectal cancer with liver metastases, treatment with standard chemotherapy changes cell- and protein-based biomarkers, although these changes are not associated with survival outcomes. In contrast, the imaging biomarker, Ktrans, offers promise to direct molecularly targeted therapies such as anti-angiogenic agents.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Capecitabina/uso terapéutico , Fluorouracilo/uso terapéutico , Oxaliplatino/uso terapéutico , Anciano , Capecitabina/farmacología , Femenino , Fluorouracilo/farmacología , Humanos , Masculino , Metástasis de la Neoplasia , Oxaliplatino/farmacología , Estudios Prospectivos
10.
J Nutr ; 150(2): 195-201, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31724705

RESUMEN

The FAO of the UN convened an Expert Working Group meeting to provide recommendations related to protein quality evaluation of Follow-up Formula for Young Children (FUF-YC) and Ready-to-Use Therapeutic Foods (RUTFs). The protein and amino acid (AA) scoring patterns for the target age groups were defined and recommendations provided on the use of currently available protein and indispensable AA digestibility data. For FUF-YC, an age category of 1-2.9 y was identified, and a matching protein requirement of 0.86 g · kg-1 · d-1 with corresponding AA requirements were recommended. For RUTF, the protein requirement recommended was 2.82 g · kg-1 · d-1, to achieve a catch-up weight gain of 10 g · kg-1 · d-1 in children recovering from severe acute malnutrition. The AA requirements were factorially derived based on the adult protein requirement for maintenance and tissue AA composition. A flowchart was proposed for the best available methods to estimate digestibility coefficients (of either protein or AAs), in the following order: human, growing pig, and rat true ileal AA digestibility values. Where this is not possible, fecal protein digestibility values should be used. The Expert Working Group recommends the use of the Protein Digestibility Corrected Amino Acid Score (PDCAAS), with existing protein digestibility values, or the Digestible Indispensable Amino Acid Score provided that individual AA digestibility values are available for protein quality evaluation using the latter score. The Group also recommends the use of ileal digestibility of protein or of AAs for plant-based protein sources, recognizing the possible effects of antinutritional factors and impaired gut function. A PDCAAS score of ≥90% can be considered adequate for these formulations, whereas with a score <90%, the quantity of protein should be increased to meet the requirements. Regardless of the protein quality score, the ability of formulations to support growth in the target population should be evaluated. Future research recommendations are also proposed based on the knowledge gaps identified.


Asunto(s)
Proteínas en la Dieta/normas , Alimentos Funcionales , Fórmulas Infantiles , Animales , Preescolar , Proteínas en la Dieta/metabolismo , Digestión , Historia del Siglo XXI , Humanos , Lactante
11.
J Magn Reson Imaging ; 52(2): 512-519, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31981400

RESUMEN

BACKGROUND: The degeneration of the corticospinal tract (CST) in chronic stroke has been widely described using diffusion tensor imaging and correlates with the extent of motor deficits. However, only a few studies have reported the early degeneration in the distal CST during the acute stage of stroke and pathological changes in the distal CST have not been described. PURPOSE: To study the microstructural changes along the CST beyond the ischemic lesion in acute stroke using diffusion kurtosis imaging (DKI). STUDY TYPE: Prospective. POPULATION: In all, 48 patients (26 males, 22 females; mean age 58.27 ± 12.89 years) with acute ischemic stroke. SEQUENCE: A DKI sequence with three b-values (0, 1000, and 2000 s/mm2 ) at 3.0T MRI. ASSESSMENT: The kurtosis and tensor parameters were derived from DKI and were compared along the length of the CST beyond the ischemic lesion between the affected and unaffected hemispheres using both voxelwise and slicewise analysis. The degree of neurological deficits was evaluated using the National Institute of Health Stroke Score (NIHSS) and the Barthel index and the clinical outcome at 3 months was evaluated using a modified Rankin scale. STATISTICAL TESTS: Paired t-tests, a linear mixed model, and multivariate linear regression. RESULTS: Voxelwise analysis demonstrated increased mean kurtosis, increased axial kurtosis, and decreased axial diffusivity in the affected CST, which were seen only at the level of the cerebral peduncle (all corrected P < 0.05). Slicewise analysis also demonstrated increased axial kurtosis in the cerebral peduncle of the affected CST (corrected P < 0.05). The axial kurtosis from slicewise analysis independently correlated with the motor component of NIHSS (ß = 0.297, P = 0.040). DATA CONCLUSION: Our findings suggest that early anterograde degeneration occurs along the axon direction in the distal CST in acute stroke, and can be detected using DKI. Moreover, acute axonal degeneration along the CST correlated with motor deficits. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1 J. Magn. Reson. Imaging 2020;52:512-519.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tractos Piramidales/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen
12.
Ann Rheum Dis ; 78(7): 934-940, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30979715

RESUMEN

OBJECTIVES: Cognitive dysfunction (CD) is common in systemic lupus erythematosus (SLE) but the cause remains unclear and treatment options are limited. We aimed to compare cognitive function in SLE and healthy controls (HCs) using both behavioural and neuroimaging techniques. METHODS: Patients with SLE with stable disease and HCs were recruited. Clinical and psychological data were collected along with a blood sample for relevant biomarkers. Neurocognitive function was assessed using tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and functional magnetic resonance imaging (fMRI) was used to examine brain responses to working memory (WM) and emotional processing (facial emotional recognition task, FERT) tasks. RESULTS: Compared with HCs (n=30), patients with SLE (n=36) scored higher on measures of depression, fatigue and had higher hsCRP (p=0.013), IL-6 (p=0.003) and B lymphocyte stimulator (p<0.001). Patients with SLE had poorer performance on a task of sustained attention (p=0.002) and had altered brain responses, particularly in default mode network (DMN) regions and the caudate, during the WM task. Higher organ damage and higher VCAM-1 were associated with less attenuation of the DMN (p=0.005 and p=0.01, respectively) and lower BOLD signal in the caudate areas (p=0.005 and p=0.001, respectively). Increased IL-6 was also associated with lower BOLD signal in caudate areas (p=0.032). CONCLUSIONS: Sustained attention was impaired in patients with SLE. Poor attenuation of the DMN may contribute to cognitive impairments in SLE and our data suggest that in addition to mood and fatigue inflammatory mechanisms and organ damage impact cognitive functioning in SLE. The multifaceted nature of CD in SLE means any therapeutic interventions should be individually tailored.


Asunto(s)
Cognición , Disfunción Cognitiva/patología , Lupus Eritematoso Sistémico/patología , Lupus Eritematoso Sistémico/psicología , Imagen por Resonancia Magnética , Adulto , Atención , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Depresión/diagnóstico por imagen , Depresión/etiología , Depresión/patología , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
14.
Eur Radiol ; 29(1): 115-123, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29926208

RESUMEN

OBJECTIVES: To test the hypothesis that abnormal corpus callosum (CC) induced by diabetes may impair inter-hemispheric sensorimotor functional connectivity (FC) that is associated with poor clinical outcome after stroke. METHODS: Forty-five patients with acute ischaemic stroke in the middle cerebral artery territory and 14 normal controls participated in the study. CC was divided into five subregions on three-dimensional T1-weighted image. The microstructural integrity of each subregion of CC was analysed by DTI and the inter-hemispheric FCs in primary motor cortex (M1-M1 FC) and primary sensory cortex (S1-S1 FC) were examined by resting-state functional magnetic resonance imaging. RESULTS: Diabetic patients (n = 26) had significantly lower fractional anisotropy (FA) in the isthmus of CC (CCisthmus) when compared with non-diabetic patients (n = 19) and normal controls (p < 0.0001). In addition, diabetic patients had the lowest M1-M1 FC (p = 0.015) and S1-S1 FC (p = 0.001). In diabetic patients, reduced FA of CCisthmus correlated with decreased M1-M1 FC (r = 0.549, p = 0.004) and S1-S1 FC (r = 0.507, p = 0.008). Decreased M1-M1 FC was independently associated with poor outcome after stroke in patients with diabetes (odds ratio = 0.448, p = 0.017). CONCLUSIONS: CC degeneration induced by diabetes impairs sensorimotor connectivity and dysfunction of motor connectivity can contribute to poor recovery after stroke in patients with diabetes. KEY POINTS: • Abnormal isthmus of corpus callosum in stroke patients with diabetes. • Abnormal isthmus of corpus callosum correlated with decreased inter-hemispheric sensorimotor connectivity. • Decreased motor connectivity correlated with poor stroke outcome in diabetic patients.


Asunto(s)
Isquemia Encefálica/complicaciones , Cuerpo Calloso/diagnóstico por imagen , Complicaciones de la Diabetes , Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso/etiología , Enfermedad Aguda , Anciano , Isquemia Encefálica/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/diagnóstico
16.
J Stroke Cerebrovasc Dis ; 28(5): 1252-1260, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30770255

RESUMEN

INTRODUCTION: To test the hypotheses that changes in the aortic pulse-wave produced by arterial stiffening are (1) propagated into cerebral small vessels, (2) associated with reduced compliance of small cerebral arterial vessels, and (3) associated with the presence of dilated perivascular spaces (PVS). METHODS: Fifteen volunteers and 19 patients with late-onset depression (LOD) were prospectively recruited, of which 6 fulfilled the criteria for treatment-resistant depression (TRD). Aortic pulse-wave velocity (PWV) was determined using Carotid-Femoral Doppler. Pulse-wave analysis (PWA) was performed using a SphygmoCor system. White-matter lesion load and PVS were scored on established MRI scales. Cerebral arterial and aqueductal cerebrospinal fluid (CSF) flow patterns were studied using quantitative phase-contrast angiography. RESULTS: Depressed patients had more PVS (P < .05) and prolongation of the width of the arterial systolic pulse-wave in the carotid arteries (P < .01). There was no significant group difference for any PWV or PWA measurement. TRD patients showed more PVS than other LOD patients (P < .05). The fractional width of the arterial systolic peak correlated significantly with augmentation index (AIx) and heart rate-corrected augmentation index (AIx75; R2 = 0.302, P < .01and R2 = 0.363, P < .01 respectively). Arterial-aqueductal delay showed a negative correlation with estimated aortic systolic pressure (PWVsys; R2 =  0.293; P < .01), AIx (R2 = -0.491; P < .01) and AIx75 (R2 = -0.310; P < .01). PVS scores correlated with AIx (R2 = 0.485; P < .01) and AIx75 (R2 = -0.292; P < .01). CONCLUSION: Our findings support the hypothesis that increased arterial pulsatility resulting from central arterial stiffness propagates directly into cerebral vessels and is associated with the development of microvascular angiopathy, characterized by dilated PVS and decreased compliance of small arterial vessels.


Asunto(s)
Aorta/fisiopatología , Arterias Cerebrales/fisiopatología , Trastornos Cerebrovasculares/fisiopatología , Trastorno Depresivo Resistente al Tratamiento/fisiopatología , Flujo Pulsátil , Rigidez Vascular , Anciano , Angiografía Cerebral/métodos , Trastornos Cerebrovasculares/diagnóstico , Trastorno Depresivo Resistente al Tratamiento/diagnóstico , Femenino , Humanos , Angiografía por Resonancia Magnética , Masculino , Estudios Prospectivos , Análisis de la Onda del Pulso , Ultrasonografía Doppler
17.
Matern Child Nutr ; 15(3): e12790, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30690903

RESUMEN

Severe and moderate acute malnutrition are among the leading causes of mortality among children in low- and middle-income countries. There is strong evidence that growth assessed anthropometrically from conception to 2 years of age marks later risk of ill health. This is central to the concept of the developmental origins of adult disease and is presumed to be related to modification of developmental processes during critical "window(s)" of vulnerability. Interventions to treat acute malnutrition have resulted in dramatic increase in the number of affected children surviving. Ensuring that these children thrive to fulfil their full physical and cognitive potential is a new challenge. Integral to this challenge is the need to be able to measure how earlier insults relate to the ability to survive and thrive to productive adulthood. Despite its obvious value, routine anthropometry does not adequately indicate how earlier adverse exposures affect more refined aspects of growth. Anthropometry is inadequate for predicting how disruption of healthy growth might modulate risk of disease or any subsequent interventions that correct this risk. A clear characterisation of healthy child growth is needed for determining which component best predicts later outcomes. The extent to which postnatal acute malnutrition is a consequence of maternal factors acting preconception or in utero and their relationship to postnatal health and long-term risk of non-communicable diseases is not clear. Body-composition measurement has significant untapped potential allowing us to translate and better understand the relationship between early insults and interventions on early growth in the short-term and long-term health outcomes.


Asunto(s)
Composición Corporal , Desarrollo Infantil , Trastornos de la Nutrición del Niño/etiología , Trastornos Nutricionales en el Feto/etiología , Desnutrición Aguda Severa/complicaciones , Antropometría , Trastornos de la Nutrición del Niño/terapia , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Países en Desarrollo , Trastornos Nutricionales en el Feto/terapia , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Desnutrición Aguda Severa/terapia
18.
J Magn Reson Imaging ; 48(2): 543-557, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29473980

RESUMEN

BACKGROUND: Previous studies have measured cerebral blood flow (CBF) with DSC-MRI using an "early time points" (ET) method based on microsphere theory. PURPOSE: To develop and assess a new ET method for absolute CBF estimation using low-dose high-temporal (LDHT) T1W-DCE-MRI. STUDY TYPE: Retrospective cohort study. SUBJECTS: Seven patients with sporadic vestibular schwannoma (VS) who underwent test-retest imaging; one patient with glioblastoma multiforme (GBM) imaged pretreatment; and 12 neurofibromatosis type 2 (NF2) patients undergoing bevacizumab treatment, imaged pre- and 90 days posttreatment. FIELD STRENGTH/SEQUENCE: LDHT-DCE-MRI was performed at 1.5 and 3.0T, using 3D spoiled gradient echo with phase cycling. DSC-MRI performed in one patient, using 3D echo-shifted multi-shot echo-planar imaging (PRESTO) at 3T. ASSESSMENT: Through Monte Carlo simulations, CBF estimation using three newly developed average contrast agent concentration (AC) -based methods (ACrPK, ACrMG, ACcomb), was compared against conventional maximum gradient (MG) approaches, at varying Rician noise levels. Reproducibility and applicability of the ACcomb method was assessed in our sporadic-VS/GBM/NF2 patient cohort, respectively. STATISTICAL TESTS: Reproducibility was measured using test-retest coefficient of variation (CoV). Pre- and posttreatment CBF values were compared using paired t-test with Bonferroni correction. RESULTS: Monte Carlo stimulations demonstrated that AC-based methods, particularly ACcomb, offered superior accuracy to conventional MG approaches. Overall test-retest CoV using the ACcomb method was 5.76 in normal-appearing white matter (NAWM). The new ACcomb method produced gray matter/white matter CBF estimates in the NF2 patient cohort of 55.9 ± 13.9/25.8 ± 3.5 on day 0; compared with 155.6 ± 17.2/128.4 ± 29.1 for the classical MG method. There was a moderate (10% using ACcomb and ACrPK) increase in CBF of NAWM 90 days post therapy (P = 0.03 and 0.005). DATA CONCLUSION: Our new AC-based method of CBF estimation offers excellent reproducibility, and displays more accuracy in both Monte Carlo analysis and clinical data application, than conventional MG-based approaches. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2018;48:543-557.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Circulación Cerebrovascular , Glioblastoma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neurilemoma/diagnóstico por imagen , Neurofibromatosis 2/diagnóstico por imagen , Anciano , Bevacizumab/uso terapéutico , Femenino , Humanos , Imagenología Tridimensional , Masculino , Microesferas , Persona de Mediana Edad , Modelos Estadísticos , Método de Montecarlo , Proyectos Piloto , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Tiempo
19.
Can J Neurol Sci ; 45(6): 620-623, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30278852

RESUMEN

Organic mercury, especially methylmercury, poisoning causes chronic neurological disease predominantly affecting the brain. There have been documented exposures from eating fish from contaminated waters in Japan and in northwestern Ontario and in Iraq from eating bread made from seed wheat treated with methylmercuric fungicide. The neurological disease is called Minamata disease in Japan. Visual field constriction due to involvement of the calcarine cortex, sensory disturbance due to involvement of the somatosensory cortex, and cerebellar ataxia due to involvement of granule cell neurons of the cerebellum are common and characteristic features due to methylmercury poisoning. Other neurological features include dysarthria, postural and action tremor, cognitive impairment, and hearing loss and dysequilibrium. In contrast, peripheral nerve disease is more characteristic of inorganic mercury intoxication. Similarly, psychosis is more typical of exposure to inorganic mercury, which has been documented in the felt hat industry ("mad hatter"). Laboratory tests (e.g., on blood and hair and toenail samples) are of limited value in the assessment of chronic neurological disease due to mercury poisoning because they may not reflect remote neuronal injury due to mercury. Methylmercury also causes injury to fetal brains during development. There is no effective treatment.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Intoxicación por Mercurio/complicaciones , Compuestos de Metilmercurio/toxicidad , Enfermedades del Sistema Nervioso/etiología , Animales , Encéfalo/efectos de los fármacos , Enfermedad Crónica/prevención & control , Humanos
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