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1.
Eur J Neurosci ; 53(8): 2901-2911, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33561905

RESUMO

Falls are associated with impairment in postural control in people with Parkinson's disease (PwPD). We aimed to predict the fall risk through models combining postural responses with clinical and cognitive measures. Also, we compared the center of pressure (CoP) between PwPD fallers and non-fallers after unpredictable external perturbations. We expected that CoP parameters combined with clinical and cognitive measures would predict fall risk. Seventy-five individuals participated in the study. CoP parameters were measured during postural responses through five trials with unpredictable translations of the support-surface in posterior direction. Range and peak of CoP were analyzed in two periods: early and late responses. Time to peak (negative peak) and recovery time were analyzed regardless of the periods. Models included the CoP parameters in early (model 1), late responses (model 2), and temporal parameters (model 3). Clinical and cognitive measures were entered into all models. Twenty-nine participants fell at least once, and 46 PwPD did not fall during 12 months following the postural assessment. Range of CoP in late responses was associated with fall risk (p = .046). However, although statistically non-significant, this parameter indicated low accuracy in predicting fall risk (area under the curve = 0.58). Fallers presented a higher range of CoP in early responses than non-fallers (p = .033). In conclusion, although an association was observed between fall risk and range of CoP in late responses, this parameter indicated low accuracy in predicting fall risk in PwPD. Also, fallers demonstrate worse postural control during early responses after external perturbations than non-fallers, measured by CoP parameters.


Assuntos
Doença de Parkinson , Acidentes por Quedas , Suscetibilidade a Doenças , Humanos , Equilíbrio Postural
2.
Gene Ther ; 27(1-2): 85-95, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31919448

RESUMO

CAR-T-cell therapy has shown considerable advance in recent years, being approved by regulatory agencies in US, Europe, and Japan for the treatment of refractory patients with CD19+ B-cell leukemia or diffuse large B-cell lymphoma. Current methods for CAR-T-cell production use viral vectors for T-cell genetic modification and can take up to 15 days to generate the infusion product. The development of simple and less costly manufacturing protocols is needed in order to meet the increasing demand for this therapy. In this present work, we generated 19BBz CAR-T cells in 8 days using a protocol based on the non-viral transposon-based vector Sleeping Beauty. The expanded cells display mostly a central memory phenotype, expressing higher levels of inhibitory receptors when compared with mock cells. In addition, CAR-T cells were cytotoxic against CD19+ leukemia cells in vitro and improved overall survival rates of mice xenografted with human RS4;11 or Nalm-6 B-cell leukemias. Infused CAR-T cells persisted for up to 28 days, showing that they are capable of long-term persistence and antitumor response. Altogether, these results demonstrate the effectiveness of our protocol and pave the way for a broader application of CAR-T-cell therapy.


Assuntos
Imunoterapia Adotiva/métodos , Leucemia de Células B/terapia , Transposases/uso terapêutico , Animais , Antígenos CD19/genética , Linhagem Celular Tumoral , Citotoxicidade Imunológica/genética , Citotoxicidade Imunológica/imunologia , Feminino , Vetores Genéticos/genética , Vetores Genéticos/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Transposases/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Neuroeng Rehabil ; 17(1): 74, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539819

RESUMO

BACKGROUND: Pharmacologic therapy is the primary treatment used to manage Parkinson's disease (PD) symptoms. However, it becomes less effective with time and some symptoms do not respond to medication. Complementary interventions are therefore required for PD. Recent studies have implemented transcranial direct current stimulation (tDCS) in combination with other modalities of interventions, such as physical and cognitive training. Although the combination of tDCS with physical and cognitive training seems promising, the existing studies present mixed results. Therefore, a systematic review of the literature is necessary. AIMS: This systematic review aims to (i) assess the clinical effects of tDCS when applied in combination with physical or cognitive therapies in people with PD and; (ii) analyze how specific details of the intervention protocols may relate to findings. METHODS: The search strategy detailed the technique of stimulation, population and combined interventions (i.e. cognitive and/or physical training). Only controlled studies were included. RESULTS: Seventeen of an initial yield of 408 studies satisfied the criteria. Studies involved small sample sizes. tDCS protocols and characteristics of combined interventions varied. The reviewed studies suggest that synergistic effects may be obtained for cognition, upper limb function, gait/mobility and posture when tDCS is combined with cognitive and/or motor interventions in PD. CONCLUSION: The reported results encourage further research to better understand the therapeutic utility of tDCS and to inform optimal clinical use in PD. Future studies in this field should focus on determining optimal stimulation parameters and intervention characteristics for maximal benefits in people with PD.


Assuntos
Doença de Parkinson/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Humanos , Masculino
4.
Obes Surg ; 33(10): 3193-3197, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37589830

RESUMO

INTRODUCTION: Few studies have evaluated the impact of bariatric surgery (BS) on thyroid function and morphology, and how it correlates to inflammatory and metabolic markers. We aimed to evaluate all those parameters together. METHODS: A longitudinal study included 70 patients with severe obesity. The bariatric group (BG) enrolled 40 patients who underwent BS, and the control group (CG) enrolled 30 patients who did not undergo BS. Both were submitted (pre- and 2nd-year) to thyroid ultrasound and laboratory analyses to determine the levels of thyroid hormones, inflammatory, and metabolic markers. RESULTS: Thyroid volume (TV) decreased after BS (-1.5 cm3), differing significantly from the CG (+0.6 cm3; p = 0.003). ΔTV was independently and positively correlated with ΔHOMA-IR (0.41 (0.11/7.16) p = 0.007) and ΔIL6 (0.02 (0.01/0.3) p = 0.016). A nonsignificant correlation between ΔTV and ΔBMI was detected (0.38 (-0.01/0.09) p = 0.152). We also observed a negative correlation between ΔTV and ΔTSH (-2.03 (-2.87/-1.19) p = 0.000) and ΔT3/T4 ratio (-0.06 (-0.09/-0.02) p = 0.001). TSH had a nonsignificant reduction with BS (-0.3872 vs. -0.2483 p = 0.128). The conversion of T4 to T3 had a significant increase after BS, as demonstrated by the T3/T4 ratio (+5.16 p = 0.01). Despite an increase in the prevalence of thyroid nodules in the BG, it was not statistically significant (p = 0.340). CONCLUSION: BS was associated with a reduction in TV and a nonstatistically significant reduction in TSH. The variations in TV were related to the metabolic markers and inflammatory changes. An increase in the conversion of T4 to T3 with BS was detected, possibly related to inflammatory improvement.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Humanos , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/cirurgia , Estudos Longitudinais , Obesidade Mórbida/cirurgia , Tireotropina
5.
Plants (Basel) ; 11(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432754

RESUMO

The genus Coffea comprises more than 100 species, of which the most commercially important are Coffea arabica and Coffea canephora. The latter is a self-incompatible plant with high natural genetic variability. The detection of polymorphism at the DNA level by molecular markers allowed significant progress with the selection of superior plants. The objective of this study was the molecular characterization of C. canephora using microsatellite markers. To this end, a population of forty-four C. canephora genotypes and one C. arabica genotype, was evaluated with 21 primers. These primers identified 61 alleles in the population and between 2 and 5 alleles per locus. The information index indicated a high level of polymorphism of the analyzed markers. According to the observed and expected heterozygosity, the genetic diversity in the population is high. The overall inbreeding coefficient of the population detected high heterozygosity and zero inbreeding within this population. Genetic diversity among the accessions was also evaluated by the unweighted pair-group method based on arithmetic averages (UPGMA). Six groups were formed based on Mojena's cutting rule and three using the Bayesian approach. These results confirmed the existence of genetic diversity, genetic variability and a potential for selection in future breeding efforts involving the 45 genotypes studied.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36094136

RESUMO

Summary: There is a close association between obesity and type 2 diabetes (T2D). The value of weight loss in the management of patients with T2D has long been known. Loss of 15% or more of body weight can have a disease-modifying effect in people with diabetes inducing remission in a large proportion of patients. Very low-carbohydrate ketogenic diets (VLCKDs) have been proposed as an appealing nutritional strategy for obesity management. The diet was shown to result in significant weight loss in the short, intermediate, and long terms and improvement in body composition parameters as well as glycemic and lipid profiles. The reported case is a 35-year-old man with obesity, dyslipidemia, and T2D for 5 years. Despite the use of five antidiabetic medications, including insulin, HbA1c was 10.1%. A VLCKD through a commercial multidisciplinary weight loss program (PnK method) was prescribed and all medications were discontinued. The method is based on high-biological-value protein preparations and has 5 steps, the first 3 steps (active stage) consist of a VLCKD (600-800 kcal/d) that is low in carbohydrates (<50 g daily from vegetables) and lipids. The amount of proteins ranged between 0.8 and 1.2 g/kg of ideal body weight. After only 3 months, the patient lost 20 kg with weight normalization and diabetes remission, and after 2 years of follow-up, the patient remained without the pathologies. Due to the rapid and significant weight loss, VLCKD emerges as a useful tool in T2D remission in patients with obesity. Learning points: Obesity and type 2 diabetes (T2D) are conditions that share key pathophysiological mechanisms. Loss of 15% or more of body weight can have a disease-modifying effect in people with T2D inducing remission in a large proportion of patients. Diabetes remission should be defined as a return of HbA1c to <6.5% and which persists for at least 3 months in the absence of usual glucose-lowering pharmacotherapy. The very low-carbohydrate ketogenic diet (VLCKD) is a nutritional approach that has significant beneficial effects on anthropometric and metabolic parameters. Due to the rapid and significant weight loss, VLCKD emerges as a useful tool in T2D remission in patients with obesity.

7.
Obes Surg ; 31(12): 5383-5390, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34558025

RESUMO

PURPOSE: Obesity is one of the major public health problems worldwide and bariatric surgery is considered the gold standard treatment for severe obesity. Although the literature supports the safety and efficacy of the very low-calorie ketogenic diet (VLCKD) in patients with obesity, there is no study analyzing the use in case of failure or weight regain after bariatric surgery. This work has the purpose of assessing the response to a VLCKD (Pnk® method) in this population. METHODS: We have conducted an observational, retrospective, and descriptive study with the analysis of medical charts of private offices where patients were examined between 2014 and 2019, totalizing 11 participants who underwent Roux-en-Y gastric bypass (RYGB) without a reduction of 50% in body weight excess or any weight regain after the surgery. The patients followed the first stage of a commercial weight loss program (Pnk® method) which consists of a VLCKD (600-800 kcal/day), low in carbohydrates and lipids. RESULTS: A significant reduction was observed (p-value < 0.05) in weight, body mass index (BMI), abdominal circumference (AC), and glycated hemoglobin (A1C) post-ketogenic diet. Uric acid, transaminases, urea, and creatinine values did not show differences between pre- and post-ketosis. During the course of the study, no serious adverse events were reported. CONCLUSION: This study has shown that the ketogenic diet can be recommended as an effective and safe treatment for patients who progressed with insufficient weight loss or regain after bariatric surgery.


Assuntos
Cirurgia Bariátrica , Dieta Cetogênica , Derivação Gástrica , Obesidade Mórbida , Dieta Cetogênica/métodos , Humanos , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Aumento de Peso
8.
Parkinsonism Relat Disord ; 93: 62-65, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34808519

RESUMO

INTRODUCTION: Transcranial direct current stimulation (tDCS) improves postural response to perturbation in patients with Parkinson's disease (PwPD). However, the influence of baseline characteristics such as clinical/cognitive and postural performance on the response to tDCS remains unclear. OBJECTIVE: To investigate whether baseline level of postural control (performance during sham condition) and clinical/cognitive characteristics are associated with tDCS-related changes in postural responses to external perturbations in PwPD. METHODS: Twenty-four PwPD participated in this study. Clinical assessment included disease severity, disease duration, levodopa equivalent dose and global cognition. Anodal tDCS protocols targeting the primary motor cortex were applied in two separate sessions (at least 2 weeks apart): active (2 mA for 20 min) and sham stimulation. Seven trials with the backward translation of the support base (20 cm/s and 5 cm) were performed after tDCS. Postural outcomes included the recovery time to stable position and onset latency of the medial gastrocnemius (MG). Pearson and Spearman correlation tests were performed. RESULTS: No significant correlations were observed between clinical/cognitive characteristics and tDCS-related changes in postural responses. Negative associations were observed between the baseline level of postural control and tDCS-related changes in postural responses for the recovery time (r = -0.657; p < 0.001) and the MG onset latency (rs = -0.539; p = 0.007). PwPD with worse baseline postural control demonstrated greater improvement after active stimulation. CONCLUSIONS: Findings suggest that tDCS-related effects on postural response to perturbation are related to the baseline level of postural control, but not to clinical characteristics in PwPD. Those with worse baseline postural control responded better to tDCS.


Assuntos
Eletromiografia/estatística & dados numéricos , Doença de Parkinson/cirurgia , Equilíbrio Postural , Estimulação Transcraniana por Corrente Contínua/estatística & dados numéricos , Idoso , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Período Pré-Operatório , Resultado do Tratamento
9.
J Gerontol A Biol Sci Med Sci ; 76(4): 561-567, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32674140

RESUMO

Parkinson's disease (PD) is often classified into tremor dominant (TD) and postural instability gait disorder (PIGD) subtypes. Degeneration of subcortical/cortical pathways is different between PD subtypes, which leads to differences in motor behavior. However, the influence of PD subtype on cortical activity during walking remains poorly understood. Therefore, we aimed to investigate the influence of PD motor subtypes on cortical activity during unobstructed walking and obstacle avoidance. Seventeen PIGD and 19 TD patients performed unobstructed walking and obstacle avoidance conditions. Brain activity was measured using a mobile functional near-infrared spectroscopy-electroencephalography (EEG) systems, and gait parameters were analyzed using an electronic carpet. Concentrations of oxygenated hemoglobin (HbO2) of the prefrontal cortex (PFC) and EEG absolute power from alpha, beta, and gamma bands in FCz, Cz, CPz, and Oz channels were calculated. These EEG channels correspond to supplementary motor area, primary motor cortex, posterior parietal cortex, and visual cortex, respectively. Postural instability gait disorder patients presented higher PFC activity than TD patients, regardless of the walking condition. Tremor dominant patients presented reduced beta power in the Cz channel during obstacle avoidance compared to unobstructed walking. Both TD and PIGD patients decreased alpha and beta power in the FCz and CPz channels. In conclusion, PIGD patients need to recruit additional cognitive resources from the PFC for walking. Both TD and PIGD patients presented changes in the activation of brain areas related to motor/sensorimotor areas in order to maintain balance control during obstacle avoidance, being that TD patients presented further changes in the motor area (Cz channel) to avoid obstacles.


Assuntos
Transtornos Neurológicos da Marcha , Oxiemoglobinas/análise , Doença de Parkinson , Equilíbrio Postural/fisiologia , Córtex Pré-Frontal , Tremor , Idoso , Eletroencefalografia/métodos , Neuroimagem Funcional/métodos , Análise da Marcha/métodos , Transtornos Neurológicos da Marcha/metabolismo , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Doença de Parkinson/classificação , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Tremor/metabolismo , Tremor/fisiopatologia , Caminhada/fisiologia , Caminhada/psicologia
10.
Neurorehabil Neural Repair ; 35(5): 406-418, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33754884

RESUMO

BACKGROUND: Dopaminergic medication improves gait in people with Parkinson disease (PD). However, it remains unclear if dopaminergic medication modulates cortical activity while walking. OBJECTIVE: We investigated the effects of dopaminergic medication on cortical activity during unobstructed walking and obstacle avoidance in people with PD. METHODS: A total of 23 individuals with PD, in both off (PDOFF) and on (PDON) medication states, and 30 healthy older adults (control group [CG]) performed unobstructed walking and obstacle avoidance conditions. Cortical activity was acquired through a combined functional near-infrared spectroscopy electroencephalography (EEG) system, along with gait parameters, through an electronic carpet. Prefrontal cortex (PFC) oxygenated hemoglobin (HbO2) and EEG absolute power from FCz, Cz, and CPz channels were calculated. RESULTS: HbO2 concentration reduced for people with PDOFF during obstacle avoidance compared with unobstructed walking. In contrast, both people with PDON and the CG had increased HbO2 concentration when avoiding obstacles compared with unobstructed walking. Dopaminergic medication increased step length, step velocity, and ß and γ power in the CPz channel, regardless of walking condition. Moreover, dopaminergic-related changes (ie, on-off) in FCz/CPz γ power were associated with dopaminergic-related changes in step length for both walking conditions. CONCLUSIONS: PD compromises the activation of the PFC during obstacle avoidance, and dopaminergic medication facilitates its recruitment. In addition, PD medication increases sensorimotor integration during walking by increasing posterior parietal cortex (CPz) activity. Increased γ power in the CPz and FCz channels is correlated with step length improvements achieved with dopaminergic medication during unobstructed walking and obstacle avoidance in PD.


Assuntos
Córtex Cerebral/fisiopatologia , Dopaminérgicos/farmacologia , Transtornos Neurológicos da Marcha , Doença de Parkinson , Desempenho Psicomotor , Caminhada , Idoso , Córtex Cerebral/diagnóstico por imagem , Eletroencefalografia , Feminino , Transtornos Neurológicos da Marcha/diagnóstico por imagem , Transtornos Neurológicos da Marcha/tratamento farmacológico , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Índice de Gravidade de Doença , Espectroscopia de Luz Próxima ao Infravermelho , Caminhada/fisiologia
11.
Neuroscience ; 473: 81-89, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455013

RESUMO

Age-related changes may affect the performance during fast walking speed. Although, several studies have been focused on the contribution of the prefrontal cortex (PFC) during challenging walking tasks, the neural mechanism underling fast walking speed in older people remain poorly understood. Therefore, the aim of this study was to investigate the influence of aging on PFC activity during overground walking at preferred and fast speeds. Twenty-five older adults (67.37 ± 5.31 years) and 24 young adults (22.70 ± 1.30 years) walked overground in two conditions: preferred speed and fast walking speed. Five trials were performed for each condition. A wireless functional near-infrared spectroscopy (fNIRS) system measured PFC activity. Gait parameters were evaluated using the GAITRite system. Overall, older adults presented higher PFC activity than young adults in both conditions. Speed-related change in PFC activity was observed for older adults, but not for young adults. Older adults significantly increased activity in the left PFC from the preferred to fast walking condition whereas young adults had similar levels of PFC activity across conditions. Our findings suggest that older adults need to recruit additional prefrontal cognitive resources to control walking, indicating a compensatory mechanism. In addition, left PFC seems to be involved in the modulation of gait speed in older adults.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Caminhada , Idoso , Marcha , Humanos , Córtex Pré-Frontal , Velocidade de Caminhada , Adulto Jovem
12.
Neurorehabil Neural Repair ; 35(8): 717-728, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34047235

RESUMO

BACKGROUND: Since people with Parkinson disease (PD) rely on limited prefrontal executive resources for the control of gait, interventions targeting the prefrontal cortex (PFC) may help in managing PD-related gait impairments. Transcranial direct current stimulation (tDCS) can be used to modulate PFC excitability and improve prefrontal cognitive functions and gait. OBJECTIVE: We investigated the effects of adding anodal tDCS applied over the PFC to a session of aerobic exercise on gait, cognition, and PFC activity while walking in people with PD. METHODS: A total of 20 people with PD participated in this randomized, double-blinded, sham-controlled crossover study. Participants attended two 30-minute sessions of aerobic exercise (cycling at moderate intensity) combined with different tDCS conditions (active- or sham-tDCS), 1 week apart. The order of sessions was counterbalanced across the sample. Anodal tDCS (2 mA for 20 minutes [active-tDCS] or 10 s [sham-tDCS]) targeted the PFC in the most affected hemisphere. Spatiotemporal gait parameters, cognitive functions, and PFC activity while walking were assessed before and immediately after each session. RESULTS: Compared with the pre-assessment, participants decreased step time variability (effect size: -0.4), shortened simple and choice reaction times (effect sizes: -0.73 and -0.57, respectively), and increased PFC activity in the stimulated hemisphere while walking (effect size: 0.54) only after aerobic exercise + active-tDCS. CONCLUSION: The addition of anodal tDCS over the PFC to a session of aerobic exercise led to immediate positive effects on gait variability, processing speed, and executive control of walking in people with PD.


Assuntos
Cognição/fisiologia , Exercício Físico/fisiologia , Marcha/fisiologia , Doença de Parkinson/terapia , Córtex Pré-Frontal/fisiopatologia , Estimulação Transcraniana por Corrente Contínua , Idoso , Estudos Cross-Over , Método Duplo-Cego , Feminino , Neuroimagem Funcional , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho , Resultado do Tratamento , Caminhada/fisiologia
13.
An Acad Bras Cienc ; 82(2): 293-304, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20563410

RESUMO

The aim of this study was to investigate the polliniferous floral sources used by Apis mellifera (L.) (africanized) in an apiary situated in Pará de Minas, Minas Gerais state, and evaluate the pollen prefences among the beehives. Two beehives of Langstroth type with frontal pollen trap collectors were used. The harvest was made from September 2007 to March 2008, with three samples of pollen pellets colected per month per beehive. The subsamples of 2 grams each were prepared according to the European standard melissopalynological method. A total of 56 pollen types were observed, identifying 43 genus and 32 families. The families that showed the major richness of pollen types were: Mimosaceae (8), Asteraceae (6), Fabaceae (3), Arecaceae (3), Euphorbiaceae (3), Rubiaceae (3), Caesalpiniaceae (2), Moraceae (2) and Myrtaceae (2). The most frequent pollen types (> 45%) were Mimosa scabrella, Myrcia and Sorocea. The results demonstrated a similarity regarding the preferences of floral sources during the major part of the time. There was a distinct utilization of floral sources among the pollen types of minor frequency. In spite of the strong antropic influence, the region showed a great polliniferous variety, which was an indicative of the potential for monofloral as well as heterofloral pollen production.


Assuntos
Abelhas/fisiologia , Comportamento Alimentar/fisiologia , Pólen/classificação , Animais , Brasil
14.
Anal Methods ; 12(48): 5801-5814, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33319873

RESUMO

This work presents the association of cloud point extraction (CPE) and electroanalysis for the selective and sensitive determination of methyl parathion (MP) in honey. The CPE step provided the pre-concentration of MP from a complex sample, in which the optimized extraction parameters (Triton X-100 concentration of 0.75% w/v, NaCl concentration of 1.0% w/v and heating time of 30 min) were investigated using a factorial design (23). The detection of MP was performed using a cathodically pre-treated boron-doped diamond (BDD) working electrode and square wave voltammetry (SWV), after a suitable dilution of the CPE extract in Britton-Robinson buffer pH 6.0 as the supporting electrolyte. MP presented three electrochemical processes over the BDD surface, but only the reduction peak at around -0.7 V was monitored for the MP determination (higher detectability). Improved reproducibility was reached by applying an in situ cleaning step (+2.0 V for 15 s) followed by a re-activation process (-2.0 V for 15 s) between measurements. Using the optimized variables, a linear range between 0.1 and 2.0 µmol L-1 was obtained for MP with a limit of detection of 0.006 µmol L-1, a 6-fold lower value when compared with the value attained without the CPE step. The experimental enrichment factor of MP was 6.1. Also, the optimized CPE allowed the determination of MP in honey samples with good accuracy (recovery between 94 and 106%), which was not possible using direct detection (without CPE) due to the matrix interference. This is the first paper that demonstrates the combination of CPE and electroanalysis for the determination of an organic compound.

15.
Neurorehabil Neural Repair ; 34(10): 915-924, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32865134

RESUMO

BACKGROUND: Declines in gait parameters are common with aging and more pronounced in tasks with increased executive demand. However, the neural correlates of age-related gait impairments are not fully understood yet. OBJECTIVES: To investigate (a) the effects of aging on prefrontal cortex (PFC) activity and gait parameters during usual walking, obstacle crossing and dual-task walking and (b) the association between PFC activity and measures of gait and executive function. METHODS: Eighty-eight healthy individuals were distributed into 6 age-groups: 20-25 (G20), 30-35 (G30), 40-45 (G40), 50-55 (G50), 60-65 (G60), and 70-75 years (G70). Participants walked overground under 3 conditions: usual walking, obstacle crossing, and dual-task walking. Changes in oxygenated and deoxygenated hemoglobin in the PFC were recorded using functional near-infrared spectroscopy. Gait spatiotemporal parameters were assessed using an electronic walkway. Executive function was assessed through validated tests. RESULTS: Between-group differences on PFC activity were observed for all conditions. Multiple groups (ie, G30, G50, G60, and G70) showed increased PFC activity in at least one of the walking conditions. Young adults (G20 and G30) had the lowest levels of PFC activity while G60 had the highest levels. Only G70 showed reduced executive function and gait impairments (which were more pronounced during obstacle crossing and dual-task walking). PFC activity was related to gait and executive function. CONCLUSIONS: Aging causes a gradual increase in PFC activity during walking. This compensatory mechanism may reach the resource ceiling in the 70s, when reduced executive function limits its efficiency and gait impairments are observed.


Assuntos
Envelhecimento/fisiologia , Função Executiva/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Caminhada/fisiologia , Adulto , Idoso , Feminino , Neuroimagem Funcional , Marcha/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
16.
Neurorehabil Neural Repair ; 34(11): 1009-1019, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33000679

RESUMO

BACKGROUND: Habituation of postural response to perturbations is impaired in people with Parkinson's disease (PD) due to deficits in cortico-basal pathways. Although transcranial direct current stimulation (tDCS) modulate cortico-basal networks, it remains unclear if it can benefit postural control in PD. OBJECTIVE: To analyze the effect of different intensities of anodal tDCS on postural responses and prefrontal cortex (PFC) activity during the habituation to the external perturbation in patients with PD (n = 24). METHODS: Anodal tDCS was applied over the primary motor cortex (M1) with 1 mA, 2 mA, and sham stimulation in 3 different sessions (~2 weeks apart) during 20 minutes immediately before the postural assessment. External perturbation (7 trials) was applied by a support base posterior translation (20 cm/s and 5 cm). Primary outcome measures included lower limb electromyography and center of pressure parameters. Measures of PFC activity are reported as exploratory outcomes. Analyses of variance (Stimulation Condition × Trial) were performed. RESULTS: Habituation of perturbation was evidenced independent of the stimulation conditions. Both active stimulation intensities had shorter recovery time and a trend for lower cortical activity in the stimulated hemisphere when compared to sham condition. Shorter onset latency of the medial gastrocnemius as well as lower cortical activity in the nonstimulated hemisphere were only observed after 2 mA concerning the sham condition. CONCLUSIONS: tDCS over M1 improved the postural response to external perturbation in PD, with better response observed for 2 mA compared with 1 mA. However, tDCS seems to be inefficient in modifying the habituation of perturbation.


Assuntos
Córtex Motor/fisiopatologia , Doença de Parkinson/fisiopatologia , Equilíbrio Postural , Córtex Pré-Frontal/fisiopatologia , Idoso , Eletromiografia , Feminino , Habituação Psicofisiológica , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Transcraniana por Corrente Contínua
17.
Neurorehabil Neural Repair ; 34(7): 589-599, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32449460

RESUMO

Background. Although dopaminergic medication improves dual task walking in people with Parkinson disease (PD), the underlying neural mechanisms are not yet fully understood. As prefrontal cognitive resources are involved in dual task walking, evaluation of the prefrontal cortex (PFC) is required. Objective. To investigate the effect of dopaminergic medication on PFC activity and gait parameters during dual task walking in people with PD. Methods. A total of 20 individuals with PD (69.8 ± 5.9 years) and 30 healthy older people (68.0 ± 5.6 years) performed 2 walking conditions: single and dual task (walking while performing a digit vigilance task). A mobile functional near infrared spectroscopy system and an electronic sensor carpet were used to analyze PFC activation and gait parameters, respectively. Relative concentrations of oxygenated hemoglobin (HbO2) from the left and right PFC were measured. Results. People with PD in the off state did not present changes in HbO2 level in the left PFC across walking conditions. In contrast, in the on state, they presented increased HbO2 levels during dual task compared with single task. Regardless of medication state, people with PD presented increased HbO2 levels in the right PFC during dual task walking compared with single task. The control group demonstrated increased PFC activity in both hemispheres during dual task compared with single task. People with PD showed increases in both step length and velocity in the on state compared with the off state. Conclusions. PD limits the activation of the left PFC during dual task walking, and dopaminergic medication facilitates its recruitment.


Assuntos
Dopaminérgicos/farmacologia , Função Executiva/efeitos dos fármacos , Marcha/efeitos dos fármacos , Levodopa/farmacologia , Doença de Parkinson/tratamento farmacológico , Córtex Pré-Frontal/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Idoso , Função Executiva/fisiologia , Feminino , Neuroimagem Funcional , Marcha/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
18.
Hum Mov Sci ; 66: 1-8, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30889495

RESUMO

INTRODUCTION: Postural instability during walking and tripping over obstacles are the main causes of falls in people with Parkinson's disease (PD). Preliminary limited evidence suggests that the length of the prospective follow-up period affects falls prediction in PD, with shorter periods leading to more accurate prediction. Thus, the primary aim of the present study was to test the performance of center of pressure (CoP) variables during obstacle crossing to predict fall risk in people with PD during subsequent periods of four, six, and 12 months. We also compared CoP variables during obstacle crossing between fallers and non-fallers. METHODS: Forty-two individuals with PD, in mild to moderate stages, completed the baseline obstacle crossing assessment and reported falls for 12 months. Participants walked at their self-selected pace and were instructed to cross an obstacle (half knee height) positioned in the middle of an 8-m long pathway. A force platform was used to analyze CoP parameters of the stance phase of the trailing limb (most affected limb). The ability of each outcome measure to predict fall risk at four, six, and 12 months was assessed using receiver operating characteristic curve analyses. RESULTS: Ten individuals (23.8%) were considered fallers at four months, twelve individuals (28.5%) at six months, and twenty-one individuals (50%) at 12 months. CoP amplitude and CoP velocity in the mediolateral direction significantly predicted fall risk at four, six, and 12 months. As judged by the area under the curve, mediolateral CoP velocity showed the best performance at four months, while mediolateral CoP amplitude showed the best performance at six months. Fallers presented greater values of mediolateral CoP velocity and amplitude than non-fallers. CONCLUSION: These findings suggest that mediolateral CoP velocity and amplitude during obstacle crossing might be useful to predict fall risk in people with PD. Therefore, larger studies are encouraged.

19.
Gait Posture ; 68: 111-114, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30471619

RESUMO

BACKGROUND: Gait is impaired in individuals with Parkinson's disease (PD). Although the effect of habitual footwear on gait spatiotemporal parameters has already been established in neurologically healthy individuals, its effects on people with PD is unknown. RESEARCH QUESTION: This study aimed to investigate the impact of habitual footwear on the step spatiotemporal parameters in people with PD. METHODS: Sixteen individuals with PD (G-PD) and 15 neurologically healthy individuals (G-HC) were assessed. Participants walked on an 8 m long pressure sensitive walkway at their preferred speed with and without their habitual footwear (3 trials per condition). Footwear included flip-flops, shoes, sneakers and sandals. The average, variability and asymmetry for step length, width, duration, and velocity and the percentage time in the swing and stance phases were calculated. RESULTS: The results showed in both groups a reduced percentage time in the swing phase and an increased step width, duration and length with footwear (F(1,29)>5.64; p<0.02). Additionally, habitual footwear increased step width variability in G-PD and G-HC (F(1,29)=3.97; p=0.06). Interestingly, only G-HC showed a higher step length asymmetry in the footwear condition than in the barefoot condition (p=0.02). Finally, only when habitual footwear was used, G-HC showed a higher step velocity asymmetry than G-PD (p=0.04). SIGNIFICANCE: These results indicate a negative influence of footwear on gait spatiotemporal parameters in both groups. Furthermore, footwear induced differences between groups. These findings indicate that footwear use is an influencing factor in studies comparing people with PD and healthy elderly. Further data are needed before definitive recommendations are made.


Assuntos
Transtornos Neurológicos da Marcha/fisiopatologia , Doença de Parkinson/fisiopatologia , Sapatos , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino
20.
Rev. Nutr. (Online) ; 37: e220091, 2024. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1559142

RESUMO

ABSTRACT Objective Verify association between the perception of food insecurity and the diet quality of the Brazilian population, applying The Brazilian Food Insecurity Scale and the Brazilian Healthy Eating Index Revised. Methods Cross-sectional study using data from the Householder Budget Survey collected in 2017/18 with two 24-hour recalls. A multinomial regression model was used with Odds Ratio and a 95% confidence interval, with the final model being the insertion of variables according to the theoretical model of hierarchy adopted. Results A total of 57,920 households were analyzed, and of these, 39.22% lived with some degree of Food Insecurity. There was a significant difference between female heads of the household, mixed race and black race, households with adults and children and living in rural regions as the three levels of AI [Food insecure] (p=<0.001), with a greater chance of food insecurity in these households. The average Brazilian Healthy Eating Index Revised for the 46,152 individuals was 54.23 points for those who were not food insecure, and 54.11 points for those who experienced severe food insecurity. Conclusion It is concluded that there is an association between the perception of food insecurity and the nutritional quality of the diet of the Brazilian population, which can lead to malnutrition and obesity.


RESUMO Objetivo Verificar a associação entre a percepção de insegurança alimentar e a qualidade da dieta da população brasileira, aplicando a Escala Brasileira de Insegurança Alimentar e o Índice de Qualidade da Dieta Revisado a partir de dois recordatórios de 24 horas. Métodos Estudo transversal que utilizou dados da Pesquisa de Orçamentos Familiares de 2017-2018. Utilizou-se o modelo de regressão multinomial com Odds Ratio e intervalo de confiança de 95%, sendo o modelo final com inserção das variáveis de acordo com o modelo teórico de hierarquia adotado. Resultados Foram analisados 57.920 domicílios, e destes, 39,22% viviam com algum grau de Insegurança Alimentar. Verificou-se diferença significativa entre pessoas do sexo feminino como chefe do domicílio, raça pardo e preto, domicílios com adultos e crianças e residir na região rural como os três níveis de Insegurança Alimentar (p=<0,001), havendo uma maior chance de insegurança alimentar nesses domicílios. A média do Índice de Qualidade da Dieta Revisado para os 46.152 indivíduos foi de 54.23 pontos para os que não apresentavam insegurança alimentar, e 54.11 pontos para aqueles que vivenciaram insegurança alimentar grave. Conclusão Conclui-se que existe associação entre a percepção de insegurança alimentar e a qualidade nutricional da dieta da população brasileira, o que pode levar à desnutrição e obesidade.


Assuntos
Humanos , Masculino , Feminino , Criança , Adulto , Idoso , Características da Família/etnologia , Dieta Saudável/etnologia , Insegurança Alimentar , Brasil/etnologia , Características de Residência/estatística & dados numéricos , Estudos Transversais , Desnutrição/etiologia , Obesidade/etiologia
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