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1.
Int J Psychiatry Clin Pract ; 27(2): 118-126, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35980319

RESUMO

OBJECTIVES: We investigated the differences in serum brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) levels and clinical symptoms with first-episode depression at different ages. METHODS: Ninety patients (15-60 years old) diagnosed with first-episode depression were enrolled as the study group, and they were divided into early-onset, adult and late-onset groups. The age-matched control groups were healthy volunteers. Serum BDNF and GDNF concentrations were determined by enzyme-linked immunosorbent assay (ELISA). GraphPad Prism 9 was used for t tests, one-way ANOVAs, chi-square tests, and correlation analyses. p < 0.05 indicated significant differences. RESULTS: Serum BDNF and GDNF levels were lower in the whole study group and the three subgroups than in the healthy groups. Illness severity, anxiety and education were higher in the early-onset than late-onset patients. Serum BDNF levels were lower in the adult than late-onset patients. Serum BDNF levels were negatively correlated with patient CGI-SI scores. After the LSD test for multiple comparisons, the results were also significant. CONCLUSIONS: Low serum BDNF and GDNF levels may be involved in the pathophysiology of first-episode depression, and there were differences in serum BDNF levels at different ages, verifying that serum BDNF and GDNF could serve as potential biomarkers of depression. KEY POINTSDepression is often conceptualised as a systemic illness with different biological mechanisms, but satisfactory explanations have not been provided thus far.The aim of our study was to investigate differences in serum BDNF and GDNF levels and their relationships with clinical symptoms in patients with first-episode depression at different ages.The potential of the neurotrophic factor hypothesis to advance the diagnosis and treatment of depression will be a very exciting new strategy for future research.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Ansiedade , Depressão
2.
Health Promot Pract ; 15(5): 638-45, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24942751

RESUMO

Most of the sodium Americans consume comes from processed and restaurant foods. An upstream global strategy to promote health is to work with local restaurants to reduce sodium content in their food offerings, while accounting for food taste and economic considerations. In urban communities, Chinese take-out restaurants serve meals with large amounts of sodium and are clustered in low-income, racial/ethnic minority communities with a high prevalence of hypertension. The objective of this study is to assess baseline knowledge, attitudes, and behaviors related to sodium use/consumption among Chinese take-out owners and chefs recruited to participate in the Philadelphia Healthy Chinese Take-Out Initiative. A cross-sectional study of 221 Chinese take-out restaurants was conducted from August 2012 to February 2013. Items measured knowledge, attitudes, and behaviors related to salt use, salt consumption, and health. Most owners/chefs knew that excess sodium consumption contributes to high blood pressure but were less aware of other health effects and of major sources of sodium in the U.S. diet. The majority were willing and able to reduce sodium content in meals if customer demand could be maintained, and they desired training in food preparation, procurement, and marketing. Findings show a need to provide education, strategies, and support to Chinese take-out owners/chefs in preparing low-salt dishes. The results of this and future studies to reduce sodium content in meals by working with restaurant owners and chefs have global health promotion implications.


Assuntos
Asiático , Culinária , Conhecimentos, Atitudes e Prática em Saúde , Restaurantes , Sódio na Dieta/administração & dosagem , China/etnologia , Estudos Transversais , Humanos , Hipertensão/etiologia , Planejamento de Cardápio , Pennsylvania , Fatores de Risco , Inquéritos e Questionários
3.
Heliyon ; 9(5): e15960, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215928

RESUMO

This study presents a design method for cultural heritage digitization using ancient Egyptian theological totems. The use of digital technology and multimedia in cultural heritage research has become an important means of cultural heritage inheritance, innovation, and dissemination with the deepening of the digital age. Ancient Egyptian theological totems were selected because their digitization is rarely discussed, although ancient Egypt has left very rich cultural heritage resources in various fields such as architecture, painting, music, and theology. The detailed digitization process was explained in three main dimensions: visual development, animation processing, and interactive design. Methods and design experiences were then summarized for each part. The study emphasizes that digital technology, as the most advanced technical means, plays a pivotal role in the inheritance, innovation, and dissemination of cultural heritage.

4.
Front Aging Neurosci ; 15: 1282962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125809

RESUMO

Background: Excessive daytime sleepiness (EDS) is a frequent nonmotor symptoms of Parkinson's disease (PD), which seriously affects the quality of life of PD patients and exacerbates other nonmotor symptoms. Previous studies have used static analyses of these resting-state functional magnetic resonance imaging (rs-fMRI) data were measured under the assumption that the intrinsic fluctuations during MRI scans are stationary. However, dynamic functional network connectivity (dFNC) analysis captures time-varying connectivity over short time scales and may reveal complex functional tissues in the brain. Purpose: To identify dynamic functional connectivity characteristics in PD-EDS patients in order to explain the underlying neuropathological mechanisms. Methods: Based on rs-fMRI data from 16 PD patients with EDS and 41 PD patients without EDS, we applied the sliding window approach, k-means clustering and independent component analysis to estimate the inherent dynamic connectivity states associated with EDS in PD patients and investigated the differences between groups. Furthermore, to assess the correlations between the altered temporal properties and the Epworth sleepiness scale (ESS) scores. Results: We found four distinct functional connectivity states in PD patients. The patients in the PD-EDS group showed increased fractional time and mean dwell time in state IV, which was characterized by strong connectivity in the sensorimotor (SMN) and visual (VIS) networks, and reduced fractional time in state I, which was characterized by strong positive connectivity intranetwork of the default mode network (DMN) and VIS, while negative connectivity internetwork between the DMN and VIS. Moreover, the ESS scores were positively correlated with fraction time in state IV. Conclusion: Our results indicated that the strong connectivity within and between the SMN and VIS was characteristic of EDS in PD patients, which may be a potential marker of pathophysiological features related to EDS in PD patients.

5.
Front Aging Neurosci ; 13: 710735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557085

RESUMO

Background: Parkinson's disease (PD) is a highly heterogeneous disease, especially in the clinical characteristics and prognosis. The PD is divided into two subgroups: tremor-dominant phenotype and non-tremor-dominant phenotype. Previous studies reported abnormal changes between the two PD phenotypes by using the static functional connectivity analysis. However, the dynamic properties of brain networks between the two PD phenotypes are not yet clear. Therefore, we aimed to uncover the dynamic functional network connectivity (dFNC) between the two PD phenotypes at the subnetwork level, focusing on the temporal properties of dFNC and the variability of network efficiency. Methods: We investigated the resting-state functional MRI (fMRI) data from 29 tremor-dominant PD patients (PDTD), 25 non-tremor-dominant PD patients (PDNTD), and 20 healthy controls (HCs). Sliding window approach, k-means clustering, independent component analysis (ICA), and graph theory analysis were applied to analyze the dFNC. Furthermore, the relationship between alterations in the dynamic properties and clinical features was assessed. Results: The dFNC analyses identified four reoccurring states, one of them showing sparse connections (state I). PDTD patients stayed longer time in state I and showed increased FNC between BG and vSMN in state IV. Both PD phenotypes exhibited higher FNC between dSMN and FPN in state II and state III compared with the controls. PDNTD patients showed decreased FNC between BG and FPN but increased FNC in the bilateral FPN compared with both PDTD patients and controls. In addition, PDNTD patients exhibited greater variability in global network efficiency. Tremor scores were positively correlated with dwell time in state I along with increased FNC between BG and vSMN in state IV. Conclusions: This study explores the dFNC between the PDTD and PDNTD patients, which offers new evidence on the abnormal time-varying brain functional connectivity and their network destruction of the two PD phenotypes, and may help better understand the neural substrates underlying different types of PD.

6.
Front Neurol ; 11: 563624, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193000

RESUMO

Background and Objective: Parkinson disease (PD) with rapid eye movement (REM) sleep behavior disorder (PD-RBD) tend to be a distinct phenotype with more severe clinical characteristics and pathological lesion when compared with PD without RBD (PD-nRBD). However, the pathological mechanism underlying PD-RBD remains unclear. We aim to use the resting-state functional magnetic resonance imaging (rs-fMRI) to explore the mechanism of PD-RBD from the perspective of internal connectivity networks. Materials and Methods: A total of 92 PD patients and 20 age and sex matched normal controls (NC) were included. All participants underwent rs-fMRI scan and clinical assessment. According to the RBD screening questionnaire (RBDSQ), PD patients were divided into two groups: PD with probable RBD (PD-pRBD) and PD without probable RBD (PD-npRBD). The whole brain was divided into 90 regions using automated anatomic labeling atlas. Functional network of each subject was constructed according to the correlation of rs-fMRI blood oxygenation level dependent signals in any two brain regions and network metrics were analyzed using graph theory approaches. Network properties among three groups were compared and correlation analysis was made using distinguishing network metrics and RBDSQ scores. Results: We found both PD-pRBD and PD-npRBD patients existed small-world characteristics. PD-pRBD showed a wider range of nodal property changes in neocortex and limbic system than PD-npRBD patients when compared with NC. Besides, PD-pRBD showed significant enhanced nodal efficiency in the bilateral thalamus and betweenness centrality in the left insula, but, reduced betweenness centrality in the right dorsolateral superior frontal gyrus when compared with PD-npRBD. Moreover, nodal efficiency in the bilateral thalamus were positively correlated with RBDSQ scores. Conclusions: Both NC and PD patients displayed small-world properties and indiscriminate global measure but PD-pRBD showed more extensive changes of nodal properties than PD-npRBD. The increased centrality role in the bilateral thalamus and the left insula, and disruption in the right dorsolateral superior frontal gyrus may play as a key role in underlying pathogenesis of PD-RBD.

7.
Front Psychiatry ; 11: 119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210851

RESUMO

BACKGROUND: Depression is common in patients with Parkinson's disease (PD). Our previous studies suggest that depressed PD patients have altered insula structures. It is, however, still unknown whether the altered structures cause disruption of insula functional networks, further contributing to depression in PD. METHODS: In the present study, 17 depressed PD patients, 17 non-depressed PD patients, and 17 normal controls were enrolled. All subjects went through neurological and psychiatric clinical assessments. Resting-state functional magnetic resonance imaging and seed-based insula functional analyses were performed to examine the insula functional connectivity alterations in PD patients. RESULTS: We found that compared with normal controls, PD patients exhibited significantly decreased insula functional connectivity widely across the whole brain. Compared with non-depressed PD patients, depressed patients showed further decreased functional connectivity in the middle frontal gyrus and inferior parietal lobe. Furthermore, connectivity between the left anterior insula and middle frontal gyrus was positively correlated with the cognitive scale score. CONCLUSION: These results suggest that insula networks were severely damaged in PD patients, and that the disrupted connection between the salience network and executive control network might contribute to depression in PD.

8.
CNS Neurosci Ther ; 26(1): 117-125, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31278861

RESUMO

AIMS: Cognitive impairment is a common symptom in the trajectory of Parkinson's disease (PD). However, the pathological underpinning is not fully known. We aimed to explore the critical structural alterations in the process of cognitive decline and its relationships with the dopaminergic deficit and the level of related cerebrospinal fluid (CSF) proteins. METHODS: Ninety-four patients with PD and 32 controls were included in this study. Neuropsychological tests were performed at baseline and after 28 months to identify which patients had normal cognition and which ones developed PD-MCI after follow-up ("converters"). Gray matter atrophy was assessed in cross-sectional and longitudinal analyses, respectively. The associations between altered GMV with dopamine transporter (DAT) results and the level of CSF proteins were assessed. RESULTS: Among the 94 patients with normal cognition at baseline, 24 (mean age, 63.1 years) developed PD-MCI after 28 months of follow-up, and 70 (mean age, 62.3 years) remained nonconverters. The converters showed significant right temporal atrophy at baseline and extensive atrophy in temporal lobe at follow-up. Progressive bilateral frontal lobe atrophy was found in the converters. Baseline right temporal atrophy was correlated with the striatal dopaminergic degeneration in the converters. No correlation was found between the right temporal atrophy and the alterations of CSF proteins. CONCLUSION: Early atrophy in temporal lobes and progressive atrophy in frontal lobes might be a biomarker for developing multidomain impairment of cognition and converting to PD-MCI. Furthermore, cognition-related temporal atrophy might be associated with dopaminergic deficit reflected by DAT scan but independent of CSF proteins in patients with PD who convert to PD-MCI.


Assuntos
Encéfalo/patologia , Disfunção Cognitiva/patologia , Doença de Parkinson/patologia , Idoso , Atrofia , Proteínas do Líquido Cefalorraquidiano/líquido cefalorraquidiano , Disfunção Cognitiva/psicologia , Corpo Estriado/patologia , Estudos Transversais , Progressão da Doença , Dopamina/metabolismo , Neurônios Dopaminérgicos/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/psicologia , Lobo Temporal/patologia
9.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o2053, 2009 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-21583715

RESUMO

The title compound, C(17)H(17)FN(4)O(4), is a derivative of ciprofloxacin [1-cyclo-propyl-6-fluoro-4-oxo-7-(1-piperazin-yl)-1,4-dihydro-quinoline-3-carboxylic acid]. The crystal packing is stabilized by inter-molecular C-H⋯O hydrogen bonds together with π-π electron ring inter-actions [centroid-centroid separations between quinoline rings of 3.5864 (11) and 3.9339 (13) Å]. A strong intra-molecular O-H⋯O hydrogen bonds is present as well as an intra-molecular C-H⋯F inter-action.

10.
Front Neurosci ; 13: 202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30914916

RESUMO

Background: Posture instability gait difficulty-dominant (PIGD) and tremor-dominant (TD) are two subtypes of Parkinson's disease (PD). The thalamus is involved in the neural circuits of both subtypes. However, which subregion of the thalamus has an influence on the PD subtypes remains unclear. Objective: To explore the core subregion of the thalamus showing a significant influence on the PD subtypes and its directional interaction between the PD subtypes. Methods: A total of 79 PD patients (43 TD and 36 PIGD) and 31 normal controls (NC) were enrolled, and the gray matter volume and perfusion characteristics in the thalamus were compared between the three groups. The subregion of the thalamus with significantly different perfusion and volume among three groups was used as the seed of a Granger causality analysis (GCA) to compare the causal connectivity between different subtypes. Results: Perfusion with an increased gradient among the three groups (TD > PIGD > NC) in the bilateral ventral intermediate nucleus (Vim) was observed, which was positively correlated with the clinical tremor scores. The GCA revealed that TD patients had enhanced causal connectivity from the bilateral Vim to the bilateral paracentral gyrus, M1 and the cerebellum compared with the NC group, while the PIGD subtype revealed an increased causal connectivity from the bilateral Vim to the bilateral premotor cortex (preM) and putamen. Additionally, there were positive correlations between the tremor scores and a causal connectivity from the Vim to the cerebellum. The connectivity from the right Vim to the right preM and the right putamen was positively correlated with the PIGD scores. Conclusion: This multilevel analysis showed that the Vim had a significant influence on the PD subtypes and that it differentially mediated the TD and PIGD-related causal connectivity pattern in PD.

11.
Neurosci Lett ; 705: 159-166, 2019 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-31026534

RESUMO

INTRODUCTION: Parkinson's disease (PD) is characterized with reduced dopamine level in the brain, resulting from the nigral degeneration. It is commonly accepted that the function of default mode network (DMN) is disturbed in PD, even in those who have no significant cognitive impairment. However, the relationship between the depletion of dopamine and DMN dysconnectivity is not fully clear. The aim of this study was to investigate the seed-based DMN connectivity and the influence of dopaminergic therapy on the DMN integrity in non-demented PD by using resting-state fMRI. MATERIAL AND METHODS: Resting-state fMRI data was collected from 24 non-demented PD patients before and after taking levodopa and 36 healthy controls (HCs). Functional connectivity (FC) was examined by a seed-based correlation approach. RESULTS: Compared with HCs, decreased DMN connectivity in PD patients was observed, a number of which were significantly improved after taking levodopa therapy. Moreover, by directly comparing the DMN connectivity between ON- and OFF-medication conditions, we found significantly enhanced FC in a set of regions of DMN in the ON- medication condition. Conversely, we also found that the PCC revealed decreased FC with left inferior temporal. CONCLUSION: DMN connectivity was found to be impaired in no-demented PD patients, and levodopa has the ability to impart a normalizing effect on DMN connectivity.


Assuntos
Encéfalo/fisiopatologia , Levodopa/uso terapêutico , Vias Neurais/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Descanso
12.
Brain Imaging Behav ; 13(1): 220-231, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29417492

RESUMO

Myelinated white matter showing diamagnetic susceptibility is important for information transfer in the brain. In Parkinson's disease (PD), the white matter is also suffering degenerative alterations. Quantitative susceptibility mapping (QSM) is a novel technique for noninvasive assessment of regional white matter ultrastructure, and provides different information of white matter in addition to standard diffusion tensor imaging (DTI). In this study, we used QSM to detect spatial white matter alterations in PD patients (n = 65) and age- and sex-matched normal controls (n = 46). Voxel-wise tract-based spatial statistics were performed to analyze QSM and DTI data. QSM showed extensive white matter involvement-including regions adjacent to the frontal, parietal, and temporal lobes-in PD patients, which was more widespread than that observed using DTI. Both QSM and DTI showed similar alterations in the left inferior longitudinal fasciculus and right cerebellar hemisphere. Further, alterations in the white matter were correlated with motor impairment and global disease severity in PD patients. We suggest that QSM may provide a novel approach for detecting white matter alterations and underlying network disruptions in PD. Further, the combination of QSM and DTI would provide a more complete evaluation of the diseased brain by analyzing different biological tissue properties.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Doença de Parkinson/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Estudos de Coortes , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/diagnóstico por imagem , Índice de Gravidade de Doença
13.
Transl Neurodegener ; 8: 36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807287

RESUMO

BACKGROUND: Different oscillations of brain networks could carry different dimensions of brain integration. We aimed to investigate oscillation-specific nodal alterations in patients with Parkinson's disease (PD) across early stage to middle stage by using graph theory-based analysis. METHODS: Eighty-eight PD patients including 39 PD patients in the early stage (EPD) and 49 patients in the middle stage (MPD) and 36 controls were recruited in the present study. Graph theory-based network analyses from three oscillation frequencies (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.073 Hz; slow-3: 0.073-0.198 Hz) were analyzed. Nodal metrics (e.g. nodal degree centrality, betweenness centrality and nodal efficiency) were calculated. RESULTS: Our results showed that (1) a divergent effect of oscillation frequencies on nodal metrics, especially on nodal degree centrality and nodal efficiency, that the anteroventral neocortex and subcortex had high nodal metrics within low oscillation frequencies while the posterolateral neocortex had high values within the relative high oscillation frequency was observed, which visually showed that network was perturbed in PD; (2) PD patients in early stage relatively preserved nodal properties while MPD patients showed widespread abnormalities, which was consistently detected within all three oscillation frequencies; (3) the involvement of basal ganglia could be specifically observed within slow-5 oscillation frequency in MPD patients; (4) logistic regression and receiver operating characteristic curve analyses demonstrated that some of those oscillation-specific nodal alterations had the ability to well discriminate PD patients from controls or MPD from EPD patients at the individual level; (5) occipital disruption within high frequency (slow-3) made a significant influence on motor impairment which was dominated by akinesia and rigidity. CONCLUSIONS: Coupling various oscillations could provide potentially useful information for large-scale network and progressive oscillation-specific nodal alterations were observed in PD patients across early to middle stages.

14.
Neurobiol Aging ; 75: 83-97, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30554085

RESUMO

In Parkinson's disease (PD), iron accumulation in the substantia nigra (SN) exacerbates oxidative stress and α-synuclein aggregation, leading to neuronal death. However, the influence of iron-related nigral degeneration on the subcortical function and global network configuration in PD remains unknown. Ninety PD patients and 38 normal controls underwent clinical assessments and multimodality magnetic resonance imaging scans. Iron accumulation in the inferior SN and disrupted functional connectivity between the bilateral striatums were observed in PD, and negative correlation between them was found in the whole population. The binarized functional network exhibited enhanced global efficiency and reduced local efficiency while the weighted functional network exhibited reduction in both, and both changes were correlated with nigral iron accumulation in PD. Mediation analysis demonstrated that the functional connectivity between bilateral striatums was a mediator between the nigral iron accumulation and weighted functional network alterations. In conclusion, our findings reveal that iron-related nigral degeneration possibly influences the functional topology mediated by striatal dysfunction, which extends the scientific understanding of PD pathogenesis.


Assuntos
Corpo Estriado/patologia , Substância Cinzenta/patologia , Ferro/metabolismo , Doença de Parkinson/patologia , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Substância Negra/patologia , alfa-Sinucleína/metabolismo
15.
Analyst ; 133(12): 1649-55, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19082066

RESUMO

In a study of calibration with HPLC data for acetaldehyde-DNPH, we have collected replicate data (5-11 points each) for 33 samples spanning the range 0.0004-3 microg of detected analyte. Over most of this range, the data uncertainty is proportional to the signal, implying that weighted least squares is required to obtain the calibration function, since minimum-variance estimation requires weights inversely proportional to the data variance. When a variance function derived from an analysis of the replicate statistics is used to assign weights, w(i) = 1/sigma(i)(2), the resulting values of chi(2) for the calibration fit are too large by a factor of 400. This implies that the method error is dominated by sample preparation rather than measurement uncertainty, and it means that in the calibration fit, the peak area should be taken as the independent variable and the amount as the dependent. In this reversed regression, the generalized LS method (GLS) is used to estimate the total method variance function from the residuals. The resulting method variance function resembles the instrumental variance, in containing constant and proportional error terms. The calibration data demand at least a cubic polynomial for adequate representation, but other response functions are statistically equivalent, with the result that this model uncertainty is comparable to the directly computed statistical uncertainty of the calibration function. In these computations, emphasis is placed on the virtues of chi(2) as a statistical figure of merit over the widely used R.

16.
J Chromatogr A ; 1206(2): 147-52, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18760790

RESUMO

For minimum-variance estimation of parameters by the method of least squares, heteroscedastic data should be weighted inversely as their variance, w(i) proportional, variant 1/sigma(i)2. Here the instrumental data variance for a commercial high-performance liquid chromatography (HPLC) instrument is estimated from 5 to 11 replicate measurements on more than 20 samples for each of four different analytes. The samples span a range of over four orders of magnitude in concentration and HPLC peak area, over which the sampling variance estimates s2 are well represented as a sum of a constant term and a term proportional to the square of the peak area. The latter contribution is dominant over most of the range used in routine HPLC analysis and represents approximately 0.2% of peak area for all four analytes studied here. It includes a contribution from uncertainty in the syringe injection volume, which is found to be +/-0.008 microL. The dominance of proportional error justifies the use of 1/x2 or 1/y2 weighting in routine calibration with such data; however, the constant variance term means that these weighting formulas are not correct in the low-signal limit relevant for analysis at trace levels. Least-squares methods for both direct and logarithmic fitting of variance sampling estimates are described. Since such estimates themselves have proportional uncertainty, direct fitting requires iterative adjustment of the weights, while logarithmic fitting does not.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Variância , Calibragem , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes
17.
Front Neurol ; 9: 334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867741

RESUMO

BACKGROUND AND OBJECTIVE: Rapid eye movement sleep behavior disorder (RBD) has a strong association with alpha synucleinpathies such as Parkinson's disease (PD) and PD patients with RBD tend to have a poorer prognosis. However, we still know little about the pathogenesis of RBD in PD. Therefore, we aim to detect the alterations of structural correlation network (SCN) in PD patients with and without RBD. MATERIALS AND METHODS: A total of 191 PD patients, including 51 patients with possible RBD (pRBD) and 140 patients with non-possible RBD, and 76 normal controls were included in the present study. Structural brain networks were constructed by thresholding gray matter volume correlation matrices of 116 regions and analyzed using graph theoretical approaches. RESULTS: There was no difference in global properties among the three groups. Significant enhanced regional nodal measures in limbic system, frontal-temporal regions, and occipital regions and decreased nodal measures in cerebellum were found in PD patients with pRBD (PD-pRBD) compared with PD patients without pRBD. Besides, nodes in frontal lobe, temporal lobe, and limbic system were served as hubs in both two PD groups, and PD-pRBD exhibited additionally recruited hubs in limbic regions. CONCLUSION: Based on the SCN analysis, we found PD-pRBD exhibited a reorganization of nodal properties as well as the remapping of the hub distribution in whole brain especially in limbic system, which may shed light to the pathophysiology of PD with RBD.

18.
Neurosci Lett ; 673: 61-66, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29501577

RESUMO

The relationship between cerebrospinal fluid (CSF) proteins and brain function in Parkinson's disease (PD) is not explained clearly. We investigated the correlations between CSF proteins and spontaneous neuronal activity in PD patients via fractional amplitude of low-frequency fluctuation (fALFF) using the Parkinson's Progression Markers Initiative database. Twenty-eight PD patients underwent resting-state functional magnetic resonance imaging in "off" status and lumbar puncture within a month. Correlation analyses between CSF proteins and fALFF value in whole brain as well as clinical assessment scores were performed. We found CSF total tau (t-tau) level was negatively correlated with fALFF in posterior cingulate gyrus. And fALFF in posterior cingulate gyrus was positively correlated with Hopkins Verbal Learning Test-Revised recognition discrimination index. Besides, alpha-synuclein (α-syn) level was correlated with fALFF in bilateral inferior frontal gyrus. This study provides evidence that CSF proteins may have a relationship with brain function related to cognitive status in PD patients.


Assuntos
Encéfalo/fisiopatologia , Proteínas do Líquido Cefalorraquidiano/análise , Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/fisiopatologia , Adulto , Idoso , Encéfalo/patologia , Mapeamento Encefálico , Bases de Dados Factuais , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/patologia , alfa-Sinucleína/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
19.
Public Health Rep ; 133(4): 472-480, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29846132

RESUMO

OBJECTIVES: Sodium reduction in restaurant foods is important because 77% of sodium in the United States is consumed by eating prepared and restaurant foods. We evaluated a sodium-reduction intervention, Healthy Chinese Take-Out Initiative, among Chinese take-out restaurants in low-income neighborhoods in Philadelphia, Pennsylvania. Our objectives were to (1) analyze changes in the sodium content of food samples and (2) collect data on changes in chefs' and owners' knowledge about the health risks of sodium overconsumption, perceptions of the need for sodium reduction, self-efficacy for lowering sodium use, and perceptions of training needs for sodium-reduction strategies. METHODS: The initiative trained chefs from 206 Chinese take-out restaurants on strategies to reduce sodium in prepared dishes. We analyzed changes in the sodium content of the 3 most frequently ordered dishes-shrimp and broccoli, chicken lo mein, and General Tso's chicken-from baseline (July-September 2012) to 36 months after baseline (July-September 2015) among 40 restaurants. We conducted a survey to examine the changes in chefs' and owners' knowledge, perceptions, and self-efficacy of sodium reduction. We used multilevel analysis and repeated-measures analysis of variance to examine effects of the intervention on various outcomes. RESULTS: We found significant reductions in the sodium content of all 3 dishes 36 months after a low-sodium cooking training intervention (coefficients range, -1.06 to -1.69, P < .001 for all). Mean knowledge (range, 9.2-11.1), perceptions (range, 4.6-6.0), and self-efficacy (range, 4.2-5.9) ( P < .001 for all) of sodium reduction improved significantly from baseline (August 2012) to posttraining (also August 2012), but perceptions of the need for sodium reduction and self-efficacy for lowering sodium use returned to baseline levels 36 months later (August 2015). CONCLUSIONS: The intervention was a useful population health approach that led to engaging restaurants in sodium-reduction practices. Local public health agencies and professionals could partner with independent restaurants to introduce environmental changes that can affect population health on a broad scale, particularly for vulnerable populations.


Assuntos
Culinária/métodos , Comportamento Alimentar/etnologia , Conhecimentos, Atitudes e Prática em Saúde , Pobreza , Restaurantes , Sódio/análise , Adulto , Negro ou Afro-Americano , Humanos , Hipertensão/prevenção & controle , Saúde das Minorias , Philadelphia , Sódio/efeitos adversos , Inquéritos e Questionários
20.
Front Hum Neurosci ; 12: 117, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29636671

RESUMO

Hemiparkinsonism duration in patients with Parkinson's disease (PD) is a key time window to study early pathology of PD. We aimed to comprehensively explore the alterations of deformation and structural network in PD patients with hemiparkinsonism, which could potentially disclose the early biomarker for PD. Thirty-one PD patients with hemiparkinsonism and 37 age- and gender- matched normal controls were included in the present study. First of all, we normalized the left hemisphere of structural images as the contralateral side to the affected limbs. Deformation-based morphometry (DBM) was conducted to evaluate the brain atrophy and/or enlargement. structural networks were constructed by thresholding gray matter volume correlation matrices of 116 regions and analyzed using graph theoretical approaches (e.g., small-worldness, global, and nodal measures). Significantly decreased deformation values were observed in the temporoparietal regions like bilateral middle temporal gyri, ipsilateral precuneus and contralateral Rolandic operculum extending to supramarginal and postcentral gyri. Lower deformation values in contralateral middle temporal gyrus were negatively correlated with higher motor impairment which was dominated by akinesia/rigidity. Moreover, nodal reorganization of structural network mainly located in frontal, temporal, subcortex and cerebellum was bilaterally explored in PD patients with hemiparkinsonism. Increased nodal properties could be commonly observed in frontal lobes. Disruption of subcortex including basal ganglia and amygdala was detected by nodal local efficiency and nodal clustering coefficient. Twelve hubs, mainly from paralimbic-limbic and heteromodal networks, were disrupted and, alternatively, 14 hubs, most of which were located in frontal lobes, were additionally detected in PD patients with hemiparkinsonism. In conclusion, during hemiparkinsonism period, mild brain atrophy in the temporoparietal regions and widespread reorganization of structural network, e.g., enhanced frontal function and disruption of basal ganglia nodes, occurred in both hemispheres. With our data, we can also argue that MTG contralateral to the affected limbs (expressing clinically verified brain atrophy) might be a potential living biomarker to monitor disease progression. Therefore, the combination of DBM and structural network analyses can provide a comprehensive and sensitive evaluation for potential pathogenesis of early PD patients with hemiparkinsonism.

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