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1.
J Frailty Aging ; 11(3): 250-255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35799429

RESUMO

BACKGROUND: Previous frailty studies found higher prevalence of frailty in female than in male participants. This was mainly attributed to the fact that compared to men, women show increased longevity. Recent studies have reported that the observed difference between sexes applies irrespectively of the age of older people. OBJECTIVES: To provide data on sex differences in incident frailty by applying both phenotypic and multi-domain frailty measures in the same population of Greek community-dwelling older people. DESIGN: Longitudinal study. SETTING: Data were drawn from the Hellenic longitudinal Investigation of Aging and Diet (HELIAD), a population-based, multidisciplinary study designed to estimate the prevalence and incidence of dementia in the Greek population. PARTICIPANTS: 1104 participants aged 65 year and above were included in this longitudinal study. This incidence cohort was re-evaluated after a mean follow-up period of 3.04±0.90 years. MEASUREMENTS: Frailty was operationalized using 5 different definitions in the same population: the Fried Frailty Phenotype (FFP) definition, the FRAIL Scale, the Frailty Index (FI), the Tilburg Frailty Indicator (TFI) and the Groningen Frailty Index (GFI). Frailty incidence was calculated a) for the whole sample, b) separately for men and women and c) after both age and sex stratification. RESULTS: Age and sex stratification revealed that irrespective of age and frailty measurement, women showed higher incidence rates of frailty than men. Specifically, frailty seems to be a condition concerning women >65 years old, but when it comes to men, it is more frequent in those aged more than 75 years old. Finally, in relation to overall frailty incidence and comparing our results to previous studies, we detected a lower frailty incidence in the Greek population. CONCLUSIONS: Differences between the two sexes indicate that when exploring the factors that are related to frailty, studies should provide data disaggregated for men and women.


Assuntos
Fragilidade , Idoso , Envelhecimento , Dieta , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica/métodos , Grécia/epidemiologia , Humanos , Incidência , Vida Independente , Estudos Longitudinais , Masculino , Caracteres Sexuais
2.
Psychiatry Res ; 306: 114270, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34775295

RESUMO

Functional brain dysconnectivity measured with resting state functional magnetic resonance imaging (rsfMRI) has been linked to cognitive impairment in schizophrenia. This study investigated the effects on functional brain connectivity of Integrated Psychological Therapy (IPT), a cognitive behavioral oriented group intervention program, in 31 patients with schizophrenia. Patients received IPT or an equal intensity non-specific psychological treatment in a non-randomized design. Evidence of improvement in executive and social functions, psychopathology and overall level of functioning was observed after treatment completion at six months only in the IPT treatment group and was partially sustained at one-year follow up. Independent Component Analysis and Isometric Mapping (ISOMAP), a non-linear manifold learning algorithm, were used to construct functional connectivity networks from the rsfMRI data. Functional brain dysconnectivity was observed in patients compared to a group of 17 healthy controls, both globally and specifically including the default mode (DMN) and frontoparietal network (FPN). DMN and FPN connectivity were reversed towards healthy control patterns only in the IPT treatment group and these effects were sustained at follow up for DMN but not FPN. These data suggest the use of rsfMRI as a biomarker for accessing and monitoring the therapeutic effects of cognitive remediation therapy in schizophrenia.


Assuntos
Esquizofrenia , Encéfalo , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa , Esquizofrenia/tratamento farmacológico , Esquizofrenia/terapia
4.
BMC Neurol ; 20(1): 400, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33138795

RESUMO

BACKGROUND: Baló's Concentric Sclerosis (BCS) is a rare heterogeneous demyelinating disease with a variety of phenotypes on Magnetic Resonance Imaging (MRI). Existing literature lacks data especially on the therapeutic approach of the disease which we intended to elucidate by means of suggesting a new possible BCS classification and introducing different therapeutic concepts based on each BCS-subgroup characteristics. METHODS: We present a retrospective study of eight treated patients with BCS-type lesions, emphasizing on MRI characteristics and differences on therapeutic maneuvers. RESULTS: Data analysis showed: at disease onset the BCS-type lesion was tumefactive (size ≥2 cm) in 6 patients, with a mean size of 2.7 cm (± 0.80 SD); a coexistence of MS-like plaques on brain MRI was identified in 7 patients of our cohort. The mean age was 26.3 years (±7.3 SD) at disease onset and the mean follow-up period was 56.8 months (range 9-132 months). According to radiological characteristics and response to therapies, we further categorized them into 3 subgroups: a) Group-1; BCS with or without coexisting nonspecific white matter lesions; poor response to intravenous methylprednisolone (IVMP); treated with high doses of immunosuppressive agents (4 patients), b) Group-2; BCS with typical MS lesions; good response to IVMP; treated with MS-disease modifying therapies (2 patients), c) Group-3; BCS with typical MS lesions; poor response to IVMP; treated with rituximab (2 patients). CONCLUSIONS: Our study introduces a new insight regarding the categorization of BCS into three subgroups depending on radiological features at onset and during the course of the disease, in combination with the response to different immunotherapies. Immunosuppressive agents such as cyclophosphamide are usually effective in BCS. However, therapeutic alternatives like anti-CD20 monoclonal antibodies or more classical disease-modifying MS therapies can be considered when BCS has also mixed lesions similar to MS. Future studies with a larger sample size are necessary to further establish these findings, thus leading to better treatment algorithms and improved clinical outcomes.


Assuntos
Esclerose Cerebral Difusa de Schilder/tratamento farmacológico , Imageamento por Ressonância Magnética , Metilprednisolona/uso terapêutico , Adolescente , Adulto , Encéfalo/patologia , Estudos de Coortes , Esclerose Cerebral Difusa de Schilder/patologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
5.
Postgrad Med ; 131(7): 501-508, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31483196

RESUMO

Objectives: Aiginition Longitudinal Biomarker Investigation Of Neurodegeneration (ALBION) is a longitudinal ongoing study initiated in 2018 that takes place in the Cognitive Disorders Clinic of Aiginition Hospital of the National and Kapodistrian University of Athens. Its aim is to address several research questions concerning the preclinical and prodromal stage of Alzheimer's disease and explore potential markers for early detection, prediction, and primary prevention of dementia. Methods: We here present the design and the preliminary baseline characteristics of ALBION. The sample of our study consists of people aged over 50 who are concerned about their memory but are cognitively normal (CN) or have mild cognitive deficits. Each participant undergoes an extensive assessment including several demographic, medical, social, environmental, clinical, nutritional, neuropsychological determinants and lifestyle activities. Furthermore, we are collecting data from portable devices, neuroimaging techniques and biological samples (blood, stools, CSF). All participants are assessed annually for a period of 10 years. Results: In total, 47 participants have completed the initial evaluation up to date and are divided in two groups, CN individuals (N = 26) and MCI patients (N = 21), based on their cognitive status. The participants are, on average, 64 years old, 46.3% of the sample is male with an average of 12.73 years of education. MCI patients report more comorbidities and have a lower score in the MMSE test. Regarding APOE status, 2 participants are ε4 homozygotes and 10 ε4 heterozygotes. CSF analyses (Aß42, Τ-tau, P-tau) revealed no differences between the two groups. Conclusion: The ALBION study offers an opportunity to explore preclinical dementia and identify new and tailored markers, particularly relating to lifestyle. Further investigation of these populations may provide a wider profile of the changes taking place in the preclinical phase of dementia, leading to potentially effective therapeutic and preventive strategies.


Assuntos
Doença de Alzheimer/prevenção & controle , Disfunção Cognitiva/metabolismo , Prevenção Primária , Sintomas Prodrômicos , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteínas E/genética , Biomarcadores , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Diagnóstico Precoce , Eletroencefalografia , Feminino , Neuroimagem Funcional , Grécia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Dados Preliminares , Proteínas tau/líquido cefalorraquidiano
6.
Neuroimage Clin ; 23: 101853, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31096180

RESUMO

Increased reaction time intra-subject variability (RT-ISV) in fast decision tasks has been confirmed in patients with schizophrenia and has been hypothesized to result from a deficit in the control of attention. Here, an attentional task and functional brain imaging were used to probe the neural correlates of increased RT-ISV in schizophrenia. Thirty patients and 30 age and sex matched controls performed the Eriksen flanker spatial attention task with concurrent measurement of brain activity using functional magnetic resonance imaging (fMRI). The behavioral measures included accuracy, mean, standard deviation of RT (RTSD), coefficient of variation of RT (RTCV) and ex-Gaussian model of RT distribution parameters (mu, sigma and tau). Larger mean RT and Ex-Gaussian mu was observed for patients compared to controls. The group difference was larger for incongruent (attentionally demanding) versus congruent trials confirming a deficit in the control of spatial attention for patients. Significant increase in RT-ISV measures (RTSD, sigma and tau) for patients compared to controls was observed and was not modulated by trial congruency. Attention modulation (congruency effect) resulted in activation of bilateral frontal and parietal areas that was not different between patients and controls. Right middle frontal, right superior temporal and bilateral cingulate areas were more active in controls compared to patients independent of congruency. Activation in ROIs extracted from attention (congruency) and group related areas correlated with RT-ISV measures (especially RTCV and tau). Hypo-activation of the right middle frontal area correlated with increased tau specifically in patients. Hypo-activity of the right prefrontal cortex predicted increased RT-ISV in schizophrenia. This effect was unrelated to the effects of spatial attention and might be linked to a deficit in the inhibitory control of action for these patients.


Assuntos
Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/metabolismo , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/metabolismo , Adulto , Atenção/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
7.
Radiat Prot Dosimetry ; 172(4): 409-415, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26656074

RESUMO

The aim of the present study is the estimation of radiation burden during liver chemoembolisation procedures. Organ dose and effective dose conversion factors, normalised to dose-area product (DAP), were estimated for chemoembolisation procedures using a Monte Carlo transport code in conjunction with an adult mathematical phantom. Exposure data from 32 patients were used to determine the exposure projections for the simulations. Equivalent organ (HT) and effective (E) doses were estimated using individual DAP values. The organs receiving the highest amount of doses during these exams were lumbar spine, liver and kidneys. The mean effective dose conversion factor was 1.4 Sv Gy-1 m-2 Dose conversion factors can be useful for patient-specific radiation burden during chemoembolisation procedures.


Assuntos
Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Método de Monte Carlo , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Humanos , Prognóstico , Dosagem Radioterapêutica
8.
Radiat Prot Dosimetry ; 163(2): 202-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24876338

RESUMO

Radiation protection and estimation of the radiological risk in paediatric radiology is essential due to children's significant radiosensitivity and their greater overall health risk. The purpose of this study was to estimate the organ and effective doses of paediatric patients undergoing barium meal (BM) examinations and also to evaluate the assessment of radiation Risk of Exposure Induced cancer Death (REID) to paediatric patients undergoing BM examinations. During the BM studies, fluoroscopy and multiple radiographs are involved. Since direct measurements of the dose in each organ are very difficult if possible at all, clinical measurements of dose-area products (DAPs) and the PCXMC 2.0 Monte Carlo code were involved. In clinical measurements, DAPs were assessed during examination of 51 patients undergoing BM examinations, separated almost equally in three age categories, neonatal, 1- and 5-y old. Organs receiving the highest amounts of radiation during BM examinations were as follows: the stomach (10.4, 10.2 and 11.1 mGy), the gall bladder (7.1, 5.8 and 5.2 mGy) and the spleen (7.5, 8.2 and 4.3 mGy). The three values in the brackets correspond to neonatal, 1- and 5-y-old patients, respectively. For all ages, the main contributors to the total organ and effective doses are the fluoroscopy projections. The average DAP values and absorbed doses to patient were higher for the left lateral projections. The REID was calculated for boys (4.8 × 10(-2), 3.0 × 10(-2) and 2.0 × 10(-2) %) for neonatal, 1- and 5-y old patients, respectively. The corresponding values for girl patients were calculated (12.1 × 10(-2), 5.5 × 10(-2) and 3.4 × 10(-2) %).


Assuntos
Envelhecimento/fisiologia , Fluoroscopia , Modelos Estatísticos , Doses de Radiação , Vísceras/fisiologia , Contagem Corporal Total/métodos , Absorção de Radiação , Administração Oral , Bário/administração & dosagem , Pré-Escolar , Simulação por Computador , Meios de Contraste/administração & dosagem , Humanos , Lactente , Recém-Nascido , Masculino , Método de Monte Carlo , Especificidade de Órgãos/fisiologia , Software
9.
Phys Med ; 30(4): 432-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24374260

RESUMO

OBJECTIVES: To estimate the organ equivalent doses and the effective doses (E) in patient undergoing percutaneous transhepatic biliary drainage (PTBD) examinations, using the MCNP5 and PCXMC2 Monte Carlo-based codes. METHODS: The purpose of this study is to estimate the organ doses to patients undergoing PTBD examinations by clinical measurements and Monte Carlo simulation. Dose area products (DAP) values were assessed during examination of 43 patients undergoing PTBD examination separated into groups based on the gender and the dimensions and location of the beam. RESULTS: Monte Carlo simulation of photon transport in male and female mathematical phantoms was applied using the MCNP5 and PCXMC2 codes in order to estimate equivalent organ doses. Regarding the PTBD examination the organ receiving the maximum radiation dose was the lumbar spine. The mean calculated HT for the lumbar spine using the MCNP5 and PCXMC2 methods respectively, was 117.25 mSv and 131.7 mSv, in males. The corresponding doses were 139.45 mSv and 157.1 mSv respectively in females. The HT values for organs receiving considerable amounts of radiation during PTBD examinations were varied between 0.16% and 73.2% for the male group and between 1.10% and 77.6% for the female group. E in females and males using MCNP5 and PCXMC2.0 was 5.88 mSv and 6.77 mSv, and 4.93 mSv and 5.60 mSv. CONCLUSION: The doses remain high compared to other invasive operations in interventional radiology. There is a reasonable good coincidence between the MCNP5 and PCXMC2.0 calculation for most of the organs.


Assuntos
Angiografia/métodos , Ductos Biliares/cirurgia , Colangiografia/métodos , Drenagem/métodos , Método de Monte Carlo , Doses de Radiação , Angiografia/efeitos adversos , Colangiografia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco
10.
Radiat Prot Dosimetry ; 157(3): 355-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23765072

RESUMO

The estimation of the radiological risk in the case of children is of particular importance due to their enhanced radiosensitivity when compared with that of adult patients. The purpose of this study is to estimate the organ and effective doses of paediatric patients undergoing micturating cystourethrography examinations. Since direct measurements of the dose in each organ are very difficult, dose-area products of 90 patients undergoing cystourethrography examinations were recorded and used with two Monte Carlo codes, MCNP5 and PCXMC2.0, to assess the organ doses in these procedures. The organs receiving the highest radiation doses were the urinary bladder (ranging from 1.9 mSv in the newborn to 4.7 mSv in a 5-y old patient) and the large intestines (ranging from 1.5 mSv in the newborn to 3.1 mSv in the 5-y old patient). For all ages the main contributors to the total organ or effective doses are the fluoroscopy projections compared with the radiographs. There was a reasonable agreement between the dose estimates provided by PCXMC v2.0 and MCNP5 for most of the organs considered in this study. In special cases, there were systematic disagreements in organ doses such as in the skeleton, gonads and oesophagus due to the anatomical differences between patient anatomic models employed by the two codes.


Assuntos
Método de Monte Carlo , Doses de Radiação , Doenças da Bexiga Urinária/diagnóstico por imagem , Urografia/normas , Adolescente , Adulto , Criança , Pré-Escolar , Simulação por Computador , Feminino , Fluoroscopia/métodos , Humanos , Lactente , Recém-Nascido , Modelos Teóricos , Imagens de Fantasmas , Medição de Risco , Urografia/métodos
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