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1.
Neuroradiology ; 65(11): 1589-1604, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37486421

RESUMEN

PURPOSE: To evaluate the ability of neurite orientation dispersion and density imaging (NODDI) for detecting white matter (WM) microstructural abnormalities in minimal hepatic encephalopathy (MHE). METHODS: Diffusion-weighted images, enabling the estimation of NODDI and diffusion tensor imaging (DTI) parameters, were acquired from 20 healthy controls (HC), 22 cirrhotic patients without MHE (NHE), and 15 cirrhotic patients with MHE. Tract-based spatial statistics were used to determine differences in DTI (including fractional anisotropy [FA] and mean/axial/radial diffusivity [MD/AD/RD]) and NODDI parameters (including neurite density index [NDI], orientation dispersion index [ODI], and isotropic volume fraction [ISO]). Voxel-wise analyses of correlations between diffusion parameters and neurocognitive performance determined by Psychometric Hepatic Encephalopathy Score (PHES) were completed. RESULTS: MHE patients had extensive NDI reduction and rare ODI reduction, primarily involving the genu and body of corpus callosum and the bilateral frontal lobe, corona radiata, external capsule, anterior limb of internal capsule, temporal lobe, posterior thalamic radiation, and brainstem. The extent of NDI and ODI reduction expanded from NHE to MHE. In both MHE and NHE groups, the extent of NDI change was quite larger than that of FA change. No significant intergroup difference in ISO/MD/AD/RD was observed. Tissue specificity afforded by NODDI revealed the underpinning of FA reduction in MHE. The NDI in left frontal lobe was significantly correlated with PHES. CONCLUSION: MHE is characterized by diffuse WM microstructural impairment (especially neurite density reduction). NODDI can improve the detection of WM microstructural impairments in MHE and provides more precise information about MHE-related pathology than DTI.

2.
Arch Gynecol Obstet ; 307(6): 1873-1882, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36897397

RESUMEN

PURPOSE: This study aimed to compare the efficacy of a special kind of intrauterine balloon (IUB) and that of an intrauterine contraception device (IUD) for patients with intrauterine adhesions (IUAs) after transcervical resection of adhesion (TCRA). METHODS: In this retrospective cohort study, after TCRA, 31 patients received a special IUB, and 38 patients received an IUD. The Fisher exact test, logistic regression method, Kaplan-Meier method and Cox proportional hazards regression model were used for statistical analysis. A two-sided value of P < 0.05 was considered statistically significant. RESULTS: The readhesion rate significantly differed between the IUB group and IUD group, at 15.39% and 54.06%, respectively (P = 0.002). For recurrent moderate IUA, patients in the IUB group had lower scores than patients in the IUD group (P = 0.035). There was a significant difference in the intrauterine pregnancy rate of IUA patients in the IUB group and IUD group after treatment, with rates of 55.56% and 14.29%, respectively (P = 0.015). CONCLUSION: Patients in the special IUB group had better outcomes than those in the IUD group, which has a certain guiding significance for clinical work.


Asunto(s)
Dispositivos Intrauterinos , Adherencias Tisulares , Taponamiento Uterino con Balón , Enfermedades Uterinas , Femenino , Humanos , Embarazo , Histeroscopía/métodos , Dispositivos Intrauterinos/efectos adversos , Índice de Embarazo , Estudios Retrospectivos , Adherencias Tisulares/etiología , Adherencias Tisulares/cirugía , Enfermedades Uterinas/cirugía
3.
Chem Biodivers ; 20(2): e202201111, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36546830

RESUMEN

Leptosperols C-G (1-5), five new phenylpropanoyl phloroglucinol derivatives were isolated from the leaves of Leptospermum scoparium. Compounds 1-3 are phenylpropanoyl phloroglucinol-sesquiterpene adducts with new carbon skeletons. Their structures with absolute configurations were elucidated by detailed spectroscopic analyses, single-crystal X-ray diffraction, and electronic circular dichroism (ECD) calculation. Compounds 2 and 3 exhibited moderate anti-inflammatory activity in zebrafish acute inflammatory models.


Asunto(s)
Leptospermum , Floroglucinol , Animales , Leptospermum/química , Estructura Molecular , Floroglucinol/química , Pez Cebra , Cristalografía por Rayos X
4.
J Clin Nurs ; 32(13-14): 3852-3862, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36081313

RESUMEN

AIMS AND OBJECTIVES: To investigate, for the first time, aberrant time-varying local brain activity in nurses following night shift-related sleep deprivation (SD) and its association with memory decline. BACKGROUND: Prior studies have elucidated alterations in static local brain activity resulting from SD in the occupations outside medical profession. DESIGN: A longitudinal study followed the STROBE recommendations. METHODS: Twenty female nurses underwent resting-state functional magnetic resonance imaging and memory function assessment (by Complex Figure Test (CFT) and the California Verbal Learning Test, Second Edition (CVLT-II)) twice, once in a rested wakefulness (RW) state and another after SD. By combining the sliding-window approach and amplitude of low-frequency fluctuation (ALFF) analysis, the dynamic ALFF (dALFF) variability was calculated to reflect the characteristics of dynamic local brain activity. RESULTS: Poor performance on the CFT and CVLT-II was observed in nurses with night shift-related SD. Reduced dALFF variability was found in a set of cognition-related brain regions (including the medial/middle/superior frontal gyrus, anterior/posterior cingulate gyrus, precuneus, angular gyrus, orbitofrontal and subgenual areas, and posterior cerebellum lobe), while increased dALFF variability was observed in the somatosensory-related, visual and auditory regions. SD-related dALFF variability alterations correlated with changes in subjects' performance on the CFT and CVLT-II. CONCLUSIONS: Night shift-related SD disturbed dynamic brain activity in high cognitive regions and induced compensatory reactions in primary perceptual cortex. Identifying dALFF variability abnormalities may broaden our understanding of neural substrates underlying SD-related cognitive alterations, especially memory dysfunction. RELEVANCE TO CLINICAL PRACTICE: Night shift-related SD is as an important occupational hazard affecting brain function in nurses. The effective countermeasure addressing the adverse outcomes of SD should be advocated for nurses. PATIENT OR PUBLIC CONTRIBUTION: Patients or public were not involved in the design and implementation of the study or the analysis and interpretation of the data.


Asunto(s)
Enfermeras y Enfermeros , Privación de Sueño , Humanos , Femenino , Estudios Longitudinales , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Trastornos de la Memoria
5.
Biochem Biophys Res Commun ; 625: 134-139, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35961137

RESUMEN

Kinds of antibiotics are used to prevent and control bacteria infections, unfortunately, the overuse and misuse of antibiotic have promoted the emergence and spread of antibiotic-resistant bacteria. Therefore, understanding the mechanism of antibiotic resistance is very important. This study explores the combined effection of metal ions and antibiotic to the drug resistance of Escherichia coli. Our results found that the minimum inhibitory concentration (MIC) increased as the ammonium ferric citrate concentration increased, especially for gentamicin antibiotic. When the Fe3+ concentration reached 300 µM, the survival of E. coli was stably restored with the increased gentamicin concentration. Exogenous Fe3+ could decrease intracellular gentamicin concentration. On the other hand, Fe3+ treatment together with gentamicin could reduce reactive oxygen species (ROS) production, characterized by decreased levels of NADH and ATP. Furthermore, ROS-scavenging enzymes of superoxide dismutase (SOD) and catalase (CAT) were up-regulated and H2O2 plus gentamicin-mediated killing was restored by Fe3+. These results may have significant implications in understanding bacterial antibiotic-resistant mechanisms based on the external Fe3+ concentration.


Asunto(s)
Infecciones por Escherichia coli , Gentamicinas , Antibacterianos/farmacología , Bacterias , Escherichia coli , Gentamicinas/farmacología , Humanos , Peróxido de Hidrógeno/farmacología , Hierro/farmacología , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno
6.
New Phytol ; 225(2): 835-847, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31491809

RESUMEN

Seed germination is a crucial transition point in plant life and is tightly regulated by environmental conditions through the coordination of two phytohormones, gibberellin and abscisic acid (ABA). To avoid unfavorable conditions, plants have evolved safeguard mechanisms for seed germination. The present contribution reports a novel function of the Arabidopsis MCM1/AGAMOUS/DEFICIENS/SRF(MADS)-box transcription factor ARABIDOPSIS NITRATE REGULATED 1 (ANR1) in seed germination. ANR1 knockout mutant is insensitive to ABA, salt and osmotic stress during the seed germination and early seedling development stages, whereas ANR1-overexpressing lines are hypersensitive. ANR1 is responsive to ABA and abiotic stresses and upregulates the expression of ABA Intolerant (ABI)3 to suppress seed germination. ANR1 and ABI3 have similar expression pattern during seed germination. Genetically, ABI3 acts downstream of ANR1. Chromatin immunoprecipitation and yeast-one-hybrid assays showed that ANR1 could bind to the ABI3 promoter to regulate its expression. In addition, ANR1 acts synergistically with AGL21 to suppress seed germination in response to ABA as evidenced by anr1 agl21 double mutant. Taken together, the results herein demonstrate that the ANR1 plays an important role in regulating seed germination and early postgermination growth. ANR1 and AGL21 together constitutes a safeguard mechanism for seed germination to avoid unfavorable conditions.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Germinación/genética , Semillas/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácido Abscísico/farmacología , Secuencia de Bases , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Germinación/efectos de los fármacos , Giberelinas/metabolismo , Proteínas de Dominio MADS/metabolismo , Mutación/genética , Presión Osmótica/efectos de los fármacos , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Unión Proteica/efectos de los fármacos , Plantones/efectos de los fármacos , Plantones/genética , Semillas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Cloruro de Sodio/farmacología , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética
7.
Appl Microbiol Biotechnol ; 103(20): 8339-8350, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31501940

RESUMEN

Bacteria from the genus Geobacillus are generally obligately thermophilic, with a unique bioenergy production capacity and unique enzymes. Geobacillus species were isolated primarily from hot springs, oilfields, and associated soils. They often exhibit unique survival patterns in these extreme oligotrophic environments. With the development of the microbial resources found in oilfields, Geobacillus spp. have been proven as valuable bacteria in many reports related to oilfields. After the isolation of Geobacillus by culture methods, more evidence was found that they possess the abilities of hydrocarbon utilization and bioemulsifier production. This paper mainly summarizes some characteristics of the Geobacillus species found in the oilfield environment, focusing on the inference and analysis of hydrocarbon degradation and bioemulsifier synthesis based on existing research, which may reveal their potential value in microbial enhanced oil recovery. It also provides references for understanding microbes in extreme environments.


Asunto(s)
Emulsionantes/metabolismo , Geobacillus/crecimiento & desarrollo , Geobacillus/metabolismo , Hidrocarburos/metabolismo , Yacimiento de Petróleo y Gas/microbiología , Geobacillus/aislamiento & purificación
8.
Mikrochim Acta ; 186(4): 227, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30848371

RESUMEN

Water-soluble nitrogen-doped carbon quantum dots (C-dots) were fabricated by microwave-induced decomposition of the precursor materials citric acid and N,N'-bis(2-aminoethyl)-1,2-ethanediamine. The C-dots were placed on portable paper strips with novel origami designs to simplified user operations. The intensity of the blue fluorescence, best measured at excitation/emission wavelengths of 330/420 nm, depends on the pH value in the range from pH 2 to 12. The C-dots on the paper stripe are shown to be a sensitive fluorescent probe for chromium(VI) via an inner filter effect. Response is linear in the 0.08 to 1 mM concentration range, and the detection limit (at S/N = 3) is 0.14 mM. The test was applied to the determination of chromium(VI) in (spiked) environmental water samples. Graphical abstract Schematic presentation of the water-soluble nitrogen-doped carbon dots (C-dots) as a fluorescent probe for Cr6+ based on an inner filter effect. The three-dimensional paper analytical device integrating C-dots was applied to the determination of Cr6+ in (spiked) environmental water samples.

9.
Phys Chem Chem Phys ; 17(23): 15124-30, 2015 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-25820836

RESUMEN

This study describes the synthesis of fluorescent polydopamine dots (PDs) through hydroxyl radical-induced degradation of polydopamine nanoparticles. The decomposition of polydopamine nanoparticles to fluorescent PDs was confirmed using transmission electron microscopy and dark-field microscopy. The analysis of PDs by using laser desorption/ionization time-of-flight mass spectrometry revealed that the PDs consisted of dopamine, 5,6-dihydroxyindole, and trihydroxyindole units. Oligomerization and self-assembly of these units produced a broad adsorption band, resulting in an excitation-wavelength-dependent emission behavior. The maximal fluorescence of PDs appeared at 440 nm with a quantum yield of 1.2%. The coordination between the catechol groups of PDs and ferric ions (Fe(3+)) quenched the fluorescence of PDs; the limit of detection at a signal-to-noise ratio of 3 for Fe(3+) was determined to be 0.3 µM. The presence of pyrophosphate switched on the fluorescence of the PD-Fe(3+) complexes. Compared to the other reported methods for sensing Fe(3+), PDs provided simple, low-cost, and reusable detection of Fe(3+).


Asunto(s)
Radical Hidroxilo/química , Indoles/química , Nanopartículas/química , Polímeros/química , Transporte de Electrón , Compuestos Férricos/química , Nanopartículas/metabolismo , Nanopartículas/ultraestructura , Teoría Cuántica , Espectrometría de Fluorescencia
10.
Analyst ; 139(6): 1436-41, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24490204

RESUMEN

This study presents a single, resettable, and sensitive molecular beacon (MB) used to operate molecular-scale logic gates. The MB consists of a random DNA sequence, a fluorophore at the 5'-end, and a quencher at the 3'-end. The presence of Hg(2+), Ag(+), and coralyne promoted the formation of stable T-Hg(2+)-T, C-Ag(+)-C, and A2-coralyne-A2 coordination in the MB probe, respectively, thereby driving its conformational change. The metal ion or small molecule-mediated coordination of mismatched DNA brought the fluorophore and the quencher into close proximity, resulting in collisional quenching of fluorescence between the two organic dyes. Because thiol can bind Hg(2+) and remove it from the T-Hg(2+)-T-based MB, adding thiol to a solution of the T-Hg(2+)-T-based MB allowed the fluorophore and the quencher to be widely separated. A similar phenomenon was observed when replacing Hg(2+) with Ag(+). Because Ag(+) strongly binds to iodide, cyanide, and cysteine, they were capable of removing Ag(+) from the C-Ag(+)-C-based MB, restoring the fluorescence of the MB. Moreover, the fluorescence of the A2-coralyne-A2-based MB could be switched on by adding polyadenosine. Using these analytes as inputs and the MB as a signal transducer, we successfully developed a series of two-input, three-input, and set-reset logic gates at the molecular level.


Asunto(s)
Alcaloides de Berberina/análisis , Computadores Moleculares , ADN/química , Colorantes Fluorescentes/química , Mercurio/análisis , Plata/análisis , Emparejamiento Base , Secuencia de Bases , Técnicas Biosensibles , Datos de Secuencia Molecular , Espectrometría de Fluorescencia
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(8): 604-8, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-23965869

RESUMEN

OBJECTIVE: To investigate the changes in the levels of interleukin-17 (IL-17) and transforming growth factor beta 1 (TGF-ß1) in serum and bronchoalveolar lavage fluid (BALF) and their clinical significance among children with asthma. METHODS: Fifty-six children with asthma were divided into moderate or severe asthma (n=37) and mild asthma groups (n=19) and 18 children without asthma were selected as the control group. Cells in BALF were counted under a microscope. The levels of IL-17 and TGF-ß1 in serum and BALF were measured using ELISA. RESULTS: were no significant differences in total cell count and percentage of macrophages between the two asthma groups and the control group (P>0.05). The percentages of neutrophils, eosinophils and epithelial cells in BALF were significantly higher in the two asthma groups than in the control group (P<0.05). The two asthma groups had significantly higher levels of IL-17 and TGF-ß1 in serum and BALF than the control group (P<0.05), and the moderate or severe asthma group had significantly higher levels of IL-17 and TGF-ß1 in serum and BALF than the mild asthma group (P<0.05). Levels of IL-17 and TGF-ß1 in serum were significantly positively correlated with those in BALF (r=0.935 and 0.943, P<0.05 for both). In children with asthma, serum IL-17 level was significantly positively correlated with the percentage of neutrophils, eosinophils and epithelial cells in BALF (r=0.802, 0.799, and 0.674, P<0.05 for all), and a significant positive correlation was also seen between serum levels of IL-17 and TGF-ß1 (r=0.878, P<0.05). CONCLUSIONS: Levels of IL-17 and TGF-ß1 in serum and BALF are elevated in children with asthma. IL-17 and TGF-ß1 may be involved in the occurrence and development of asthma, and they play important roles in asthma attack and aggravation.


Asunto(s)
Asma/inmunología , Líquido del Lavado Bronquioalveolar/química , Interleucina-17/fisiología , Factor de Crecimiento Transformador beta1/fisiología , Asma/patología , Líquido del Lavado Bronquioalveolar/citología , Niño , Preescolar , Femenino , Humanos , Lactante , Interleucina-17/análisis , Interleucina-17/sangre , Masculino , Factor de Crecimiento Transformador beta1/análisis , Factor de Crecimiento Transformador beta1/sangre
12.
CNS Neurosci Ther ; 29(11): 3406-3415, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37208946

RESUMEN

AIMS: To investigate microstructural impairments of corticospinal tracts (CSTs) with different origins in amyotrophic lateral sclerosis (ALS) using neurite orientation dispersion and density imaging (NODDI). METHODS: Diffusion-weighted imaging data acquired from 39 patients with ALS and 50 controls were used to estimate NODDI and diffusion tensor imaging (DTI) models. Fine maps of CST subfibers originating from the primary motor area (M1), premotor cortex, primary sensory area, and supplementary motor area (SMA) were segmented. NODDI metrics (neurite density index [NDI] and orientation dispersion index [ODI]) and DTI metrics (fractional anisotropy [FA] and mean/axial/radial diffusivity [MD/AD/RD]) were computed. RESULTS: The patients with ALS showed microstructural impairments (reflected by NDI, ODI, and FA reductions and MD, AD, and RD increases) in CST subfibers, especially in M1 fibers, which correlated with disease severity. Compared with other diffusion metrics, NDI yielded a higher effect size and detected the greatest extent of CST subfibers damage. Logistic regression analyses based on NDI in M1 subfiber yielded the best diagnostic performance compared with other subfibers and the whole CST. CONCLUSIONS: Microstructural impairment of CST subfibers (especially those originating from M1) is the key feature of ALS. The combination of NODDI and CST subfibers analysis may improve diagnosing performance for ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral , Corteza Motora , Sustancia Blanca , Humanos , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Neuritas , Imagen de Difusión Tensora/métodos , Imagen de Difusión por Resonancia Magnética , Corteza Motora/diagnóstico por imagen
13.
Front Neurosci ; 17: 1144802, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37034160

RESUMEN

Background and aims: Diffusion magnetic resonance imaging (dMRI) studies have revealed microstructural abnormalities in white matter resulting from sleep deprivation (SD). This study aimed to adopt neurite orientation dispersion and density imaging (NODDI) to investigate the effect of SD on gray matter (GM) microstructural properties and its association to visuospatial memory (VSM). Methods: Twenty-four healthy women underwent two sessions of dMRI scanning and visuospatial ability assessment by Complex Figure Test (CFT), once during rested wakefulness (RW) and once after 24 h of SD. We calculated NODDI metrics, including intracellular volume fraction (ICVF), orientation dispersion index (ODI), and isotropic volume fraction (ISO). Differences in NODDI-related metrics between RW and SD were determined using a voxel-wise paired t-test. We identified an association between NODDI metrics and CFT results using Spearman's correlation coefficient. Results: Sleep deprivation worsened subjects' performance in the delayed-CFT trial. We observed no significant difference in ICVF and ODI between RW and SD. After SD, subjects showed decreases in ISO, primarily in the prefrontal cortex and temporal lobe, while exhibiting ISO increases in the anterior and posterior cerebellar lobe and cerebellar vermis. Furthermore, ISO change in the left superior, middle and inferior frontal gyrus was significantly correlated with completion time change in delayed-CFT trial performance. Conclusion: Our results suggested that SD hardly affected the density and spatial organization of neurites in GM, but the extra-neurite water molecule diffusion process was affected (perhaps resulting from neuroinflammation), which contributed to VSM dysfunction.

14.
Heliyon ; 9(8): e19318, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37664705

RESUMEN

Background: Solid pseudopapillary neoplasms (SPNs) are uncommon tumors of low malignancy with a generally favorable prognosis, mostly originating from the pancreas. To date, 12 cases of SPNs with a primary ovarian origin (SPN-Os) have been reported globally, and their detailed characteristics have not been fully elucidated. Case description: We reported the 13th SPN-O case, which occurred in a 52-year-old woman with an 18.5 cm left ovarian mass. Four imaging methods, including ultrasound, computed tomography, magnetic resonance imaging and positron emission tomography, were utilized before surgery. An elevated level of serum cancer antigen 125 was detected and a total hysterectomy plus bilateral salpingo-oophorectomy was performed. Microscopic examination revealed a typical solid pseudopapillary structure. The tumor cells were stained focally for pan-cytokeratin, synaptophysin, CD99 and CD10, while ß-catenin, vimentin and CD56 were diffusely expressed. The Ki-67 proliferation index was 3%, and immunohistochemical (IHC) staining for chromogranin-A, inhibin-a, and E-cadherin was negative. No evidence of recurrence or metastasis was observed by clinical and imaging data during a 5-month postoperative follow-up. Conclusion: This is a report of an unusual case of a primary ovarian SPN with an up-to-date review of SPN-Os. A minimum combination of imaging methods and IHC stains was proposed for SPN-Os, which may prove beneficial in clinical practice.

15.
Front Neurosci ; 16: 998541, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312008

RESUMEN

Background and aims: Resting-state functional magnetic resonance imaging (fMRI) studies using static and dynamic functional connectivity (FC) approaches have revealed brain dysfunction resulting from sleep deprivation (SD). The effects of SD on the stability of brain functional architecture remain unclear. This study investigated the functional stability (FS) changes induced by SD and its association with neurocognitive alterations. Materials and methods: In this study, we recruited 24 healthy women. All participants underwent two sessions of resting-state fMRI scanning and neurocognitive assessment. The assessments included the Digit Symbol Test, Digit Span Test, Trail-Making Test (TMT), and Complex Figure Test (CFT). Participants completed one session under rested wakefulness (RW) and one session after SD for 24 h. To estimate dynamic FC, we used the sliding window approach; and then, to characterize the FS of each voxel, we measured dynamic FC concordance over time. We used a paired t-test to identify differences in FS between RW and SD. To examine the relationship between these changes in FS and alterations in neurocognitive performance, we conducted Spearman's correlation analyses. Results: SD affected the performance of the Digit Symbol Test, Digit Span Test, and CFT. Compared with RW, subjects with SD exhibited decreased FS in the bilateral anterior and posterior cingulate gyrus and medial frontal gyrus, right superior frontal gyrus, and cerebellum posterior lobe, while they exhibited increased FS in the bilateral precentral/postcentral gyrus and supplementary motor area, right parahippocampal gyrus and fusiform gyrus, left inferior occipital gyrus, and bilateral cerebellum anterior lobe. After SD, FS changes in the right parahippocampal gyrus and fusiform gyrus were correlated with altered performance in the Digit Symbol Test and CFT. Conclusion: Our findings showed that the stability of the brain's functional architecture could be altered by SD. This stability alteration may correspond to multiple neurocognitive domain changes.

16.
Biosens Bioelectron ; 216: 114669, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36108567

RESUMEN

In this study, we demonstrate how palladium@platinum nanoparticles (Pd@Pt NPs) can be used as a nanozyme for the detection of Staphylococcus aureus (S. aureus) on a paper-based analytical device. Pt was doped with Pd to form bimetallic NPs that serve as a peroxidase mimetic, which can enhance the reaction area with a substrate (3, 3', 5, 5'-tetramethylbenzidine, TMB). After material characterization, we show the peroxidase-like activity of the Pd@Pt NPs featured a 13-times higher binding affinity value (Km) for TMB compared to horseradish peroxidase, which is currently widely used in immunoassays. By incorporating the Pd@Pt NPs in a paper-based immunoassay, we can detect protein A, the biomarker of S. aureus, within 30 min with a detection limit of 9.56 ng/mL. We have also successfully validated this nanozyme-immobilized paper-based analytical device (nPAD) for the detection of human immunoglobulin G to demonstrate the capability of the Pd@Pt NPs for different target analytes. This highly sensitive, rapid, and portable nPAD design has the potential for personalized medicine and point-of-care testing, which could expand on-site prognoses in resource-limited settings.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Biomarcadores , Peroxidasa de Rábano Silvestre , Humanos , Inmunoglobulina G , Nanopartículas del Metal/química , Paladio/química , Peroxidasas , Platino (Metal)/química , Staphylococcus aureus
17.
Front Aging Neurosci ; 14: 827500, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35370623

RESUMEN

Background and Aims: Current knowledge on the temporal dynamics of the brain functional organization in amyotrophic lateral sclerosis (ALS) is limited. This is the first study on alterations in the patterns of dynamic functional connection density (dFCD) involving ALS. Methods: We obtained resting-state functional magnetic resonance imaging (fMRI) data from 50 individuals diagnosed with ALS and 55 healthy controls (HCs). We calculated the functional connectivity (FC) between a given voxel and all other voxels within the entire brain and yield the functional connection density (FCD) value per voxel. dFCD was assessed by sliding window correlation method. In addition, the standard deviation (SD) of dFCD across the windows was computed voxel-wisely to measure dFCD variability. The difference in dFCD variability between the two groups was compared using a two-sample t-test following a voxel-wise manner. The receiver operating characteristic (ROC) curve was used to assess the between-group recognition performance of the dFCD variability index. Results: The dFCD variability was significantly reduced in the bilateral precentral and postcentral gyrus compared with the HC group, whereas a marked increase was observed in the left middle frontal gyrus of ALS patients. dFCD variability exhibited moderate potential (areas under ROC curve = 0.753-0.837, all P < 0.001) in distinguishing two groups. Conclusion: ALS patients exhibit aberrant dynamic property in brain functional architecture. The dFCD evaluation improves our understanding of the pathological mechanisms underlying ALS and may assist in its diagnosis.

18.
Acad Radiol ; 29 Suppl 3: S141-S146, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34481706

RESUMEN

RATIONALE AND OBJECTIVES: To investigate the microperfusion and water molecule diffusion alterations in sensorimotor-related areas in amyotrophic lateral sclerosis (ALS) using intravoxel incoherent motion (IVIM) magnetic resonance imaging. MATERIALS AND METHODS: IVIM data were obtained from 43 ALS patients and 31 controls. This study employed the revised ALS Functional Rating Scale (ALSFRS-R) in evaluating disease severity. IVIM-derived metrics were calculated, including diffusion coefficient (D), pseudo-diffusion coefficient, and perfusion fraction. Conventional apparent diffusion coefficient was also computed. Atlas-based analysis was conducted to detect between-group difference in these metrics in sensorimotor-related gray/white matter areas. Spearman correlation analysis was employed to establish correlation between various metrics and ALSFRS-R. RESULTS: ALS patients had perfusion fraction (× 10-3) reduction in the left presupplementary motor area (60.72 ± 16.15 vs. 71.15 ± 12.98, p = 0.016), right presupplementary motor area (61.35 ± 17.02 vs. 72.18 ± 14.22, p = 0.016), left supplementary motor area (55.73 ± 12.29 vs. 64.12 ± 9.17, p = 0.015), and right supplementary motor area (56.53 ± 11.93 vs. 63.67 ± 10.03, p = 0.020). Patients showed D (× 10-6 mm2/s) increase in a white matter tract projecting to the right ventral premotor cortex (714.20 ± 39.75 vs. 691.01 ± 24.53, p = 0.034). A negative correlation between D of right ventral premotor cortex tract and ALSFRS-R score was observed (r = -0.316, p = 0.039). CONCLUSION: These findings suggest aberrant microperfusion and water molecule diffusion in the sensorimotor-related areas in ALS patients, which are associated with motor impairment in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Imagen por Resonancia Magnética , Movimiento (Física) , Agua
19.
J Food Drug Anal ; 29(4): 544-558, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-35649139

RESUMEN

Conducting polymers (CPs) are a category of polymeric materials with conjugated main chains. The characteristic electrical and optical properties of CPs can be fine-tuned through controlling the doping states of CPs. Because of their long-term stability in water, CPs have been demonstrated as electroactive biointerfaces and electrode materials especially in aqueous environments. Serving as multifunctional interfaces and organic electrodes for the integration bioelectronics and devices, CPs have been studied and applied in various biological applications. This paper provides a review of conducting polymer-based electrochemical sensors, particularly those used in biological fields. General conducting polymers and derivatives and their main electrochemical sensing platforms with different design of devices are introduced. Cyclic voltammetry, differential pulse voltammetry, chronoamperometry, electrochemical impedance spectroscopy, and quartz crystal microbalance methods and their features are then explored as detection methods for the analysis of drugs and food. To enhance the sensitivity and lower the detection limit of sensing platforms, various CP-based nanocomposites have been designed and developed. Although the electrodes made of CP-based nanocomposites usually outperform those made of pristine CPs, more systematic studies are required to provide insights into the design of nanocomposite-based electrodes. More applications of CP-based sensors for advanced food and drug analyses are expected.


Asunto(s)
Técnicas Biosensibles , Polímeros , Técnicas Biosensibles/métodos , Electrodos , Polímeros/química , Agua
20.
Front Neurol ; 12: 744688, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721270

RESUMEN

Purpose: Static and dynamic analyses for identifying functional connectivity (FC) have demonstrated brain dysfunctions in amyotrophic lateral sclerosis (ALS). However, few studies on the stability of dynamic FC have been conducted among ALS patients. This study explored the change of functional stability in ALS and how it correlates with disease severity. Methods: We gathered resting-state functional magnetic resonance data from 20 patients with ALS and 22 healthy controls (HCs). The disease severity was assessed with the Revised ALS Functional Rating Scale (ALSFRS-R). We used a sliding window correlation approach to identify dynamic FC and measured the concordance of dynamic FC over time to obtain the functional stability of each voxel. We assessed the between-group difference in functional stability by voxel-wise two-sample t-test. The correlation between the functional stability index and ALSFRS-R in ALS patients was evaluated using Spearman's correlation analysis. Results: Compared with the HC group, the ALS group had significantly increased functional stability in the left pre-central and post-central gyrus and right temporal pole while decreased functional stability in the right middle and inferior frontal gyrus. The results revealed a significant correlation between ALSFRS-R and the mean functional stability in the right temporal pole (r = -0.452 and P = 0.046) in the ALS patients. Conclusions: ALS patients have abnormal stability of brain functional architecture, which is associated with the severity of the disease.

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