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1.
Front Neurol ; 12: 744688, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721270

RESUMO

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.

2.
Org Biomol Chem ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34787150

RESUMO

A general and efficient strategy for the one-pot synthesis of isothiocoumarin-1-ones has been developed via the base-promoted 6-endo-dig thioannulation of o-alkynyl oxime ethers using the cheap and readily available Na2S as the sulfur source. Mechanistic studies disclosed that the reaction proceeded through two C-S bond formations, N-O bond cleavage and the final hydrolysis of imines.

3.
Huan Jing Ke Xue ; 42(10): 4933-4941, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581137

RESUMO

A total of 43 surface soil samples were collected from Yinchuan farmland and high performance liquid chromatography(HPLC) was used to measure the concentrations of oxytetracycline(OTC), tetracycline(TC), chlortetracycline(CTC), and doxycycline(DOC). The pollution characteristics and spatial distribution of TC were further analyzed using spatial Kriging interpolation, and the ecological risks of OTC, TC, CTC, and DOC in farmland soils were also assessed. Tetracycline antibiotics were detected in all the soil samples at concentrations ranging from 40.68 to 1074.42 µg·kg-1 and an average of 462.24 µg·kg-1. The average proportions were ranked ΣTCs: CTC(69.26%) > OTC(16.34%) > TC(12.86%) > DOC(1.54%), and CTC pollution was the most serious among. The space tended to be high in the middle and low in the periphery, but the concentrations of TC were highest in the northwest. The average contents of ΣTCs in different soils was ranked as follows:vegetable field(596.01 µg·kg-1) > pasture(487.04 µg·kg-1) > cultivated land(437.52µg·kg-1) > garden plot(404.99 µg·kg-1). The average risk values of OTC, TC, CTC, and DOC in farmland soils were 0.14, 0.69, 0.14, and 1.02, respectively. TC and DOC represented a high level of risk in 23.26% and 6.98% of the samples, respectively, which requires particular attention.


Assuntos
Clortetraciclina , Oxitetraciclina , Poluentes do Solo , Antibacterianos , Fazendas , Medição de Risco , Solo , Poluentes do Solo/análise , Tetraciclina
4.
Angew Chem Int Ed Engl ; 60(49): 25878-25883, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34585471

RESUMO

The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature-dependent time-resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of "self-doping" for realizing high-efficiency nondoped OLEDs. Interestingly, this "compositionally" pure film actually behaves as a film with a dopant (quasi-equatorial form) in a matrix (quasi-axial form). The concentration-induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The "self-doping" OLED prepared with the newly developed TADF emitter TP2P-PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll-off.

5.
Small ; 17(43): e2103127, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34510742

RESUMO

Conjugated polymers (CPs) are capable of coordinating the electron coupling phenomenon to bestow powerful optoelectronic features. The light-harvesting and light-amplifying properties of CPs are extensively used in figuring out the biomedical issues with special emphasis on accurate diagnosis, effective treatment, and precise theranostics. This review summarizes the recent progress of CP materials in bioimaging, cancer therapeutics, and introduces the design strategies by rationally tuning the optical properties. The recent advances of CPs in bioimaging applications are first summarized and the challenges to clear the future directions of CPs in the respective area are discussed. In the following sections, the focus is on the burgeoning applications of CPs in phototherapy of the tumor, and illustrates the underlying photo-transforming mechanism for further molecular designing. Besides, the recent progress in the CPs-assistant drug therapy, mainly including drug delivery, gene therapeutic, the optical-activated reversion of tumor resistance, and synergistic therapy has also been discussed elaborately. In the end, the potential challenges and future developments of CPs on cancer diagnosis and therapy are also illuminated for the improvement of optical functionalization and the promotion of clinical translation.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Fototerapia , Polímeros , Nanomedicina Teranóstica
6.
PLoS One ; 16(8): e0254457, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34398887

RESUMO

The study explored the 3D numerical solution of an unsteady Ag-MgO/water hybrid nanofluid flow with mass and energy transmission generated by a wavy rotating disc moving up and down. The nanofluid is generated in the context of Ag-MgO nanomaterials. Magnesium oxide and silver nanoparticles have been heavily reported to have broad-spectrum antibacterial operations among metal oxides and metals. Silver nanoparticles are without a doubt the most commonly used inorganic nanoparticles, with numerous innovations in biomaterial's detection and antimicrobial operations. However, in current paper, the intention of the analysis is to boost thermal energy transmitting rates for a range of industrial implementations. When compared to a flat surface, energy transition is increased up to 15% due to the wavy swirling surface. The problem has been formulated as a system of PDEs, which included the Navier Stokes and Maxwell equations. Following that, the modeled equations are reduced to a dimensionless system of differential equations. The derived equations are then solved numerically using the Parametric Continuation Method (PCM). The findings are displayed graphically and debated. The geometry of a spinning disc is thought to have a positive impact on velocity and heat energy transfer. The insertion of nanostructured materials (silver and magnesium-oxide) increased the carrier fluid's thermal properties considerably. It is more effective at dealing with low energy transmission.


Assuntos
Antibacterianos/química , Óxido de Magnésio/química , Modelos Químicos , Nanopartículas/química , Prata/química
7.
Sci Rep ; 11(1): 16458, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385502

RESUMO

In this paper, the natural convection heat transfer of water/alumina nanofluid is investigated in a closed square cavity. An oblique magnetic field is applied on the cavity of angle [Formula: see text]. There is also radiation heat transfer in the cavity. The cavity includes a high-temperature source of L-shape. A low-temperature source as a quadrant of a circle is placed at the corner of the cavity. All other walls are well insulated. The novelty of this work is a low-temperature obstacle embedded in the cavity. Simulations are conducted with a Fortran code based on the control volume method and simple algorithm. Entropy generation rate, Bejan number, and heat transfer are studied by changing different parameters. Results indicate that the highest rates of heat transfer and entropy generation have occurred for the perpendicular magnetic field at high values of the Rayleigh number. At these Rayleigh numbers, the minimum value of the Bejan number is obtained for 15° magnetic field. The magnetic field variation can lead to a change up to 53% in Nusselt number and up to 34% in generated entropy. In a weak magnetic field, the involvement of the radiation heat transfer mechanism leads to an increase in the heat transfer rate so that the Nusselt number can be increased by ten units considering the radiation heat transfer when there is no magnetic field. The maximum heat transfer rate occurs in the horizontal cavity and the minimum value in the cavity of 60° angle. For water, these values are 10.75 and 9.98 for 0 and 60 angles, respectively. Moreover, a weak magnetic field increases the heat transfer rate in the absence of the radiation mechanism, while it is reduced by considering a strong magnetic field.

8.
ACS Appl Mater Interfaces ; 13(30): 36089-36097, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34289306

RESUMO

Highly twisted electron donor (D)-electron acceptor (A)-type thermally activated delayed fluorescence (TADF) emitters can achieve high efficiency while suffering from serious structural relaxations and broad emissions. Multiple resonance (MR)-type TADF emitters can realize narrow emission. However, until now, only a few efficient MR-emitting cores are reported and custom tunning of their emission color remains a major challenge in their wider applications. In this work, by combining the conventional TADF and MR-TADF designs, we demonstrate that color tuning and narrowing the spectral width of conventional TADF emission can be easily achieved simultaneously. We select a prototypical carbonyl (C═O)/N-based MR core as a backbone and attach it with D segments of different electron-donating abilities and numbers to obtain three different TADF emitters with emissions from sky blue to green and orange-red while maintaining the narrow emission of the original MR core. The corresponding sky blue, green, and orange-red organic light-emitting diodes achieve maximum external quantum efficiencies of 20.3, 27.3, and 26.3%, respectively, and narrow full widths at half-maximum all below 0.28 eV. These results provide a new molecular design strategy for developing narrowband TADF emitters with easily tunable emissions covering the full visible range.

9.
Adv Mater ; 33(24): e2008171, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33963781

RESUMO

Single-crystalline silicon (sc-Si) is the dominant semiconductor material for the modern electronics industry. Despite their excellent photoelectric and electronic properties, the rigidity, brittleness, and nontransparency of commonly used silicon wafers limit their application in transparent flexible optoelectronics. In this study, a new type of Si microstructure, named single-crystalline Si frameworks (sc-SiFs), is developed, through a combination of wet-etching and microfabrication technologies. The sc-SiFs are self-supported, flexible, lightweight, tailorable, and highly transparent. They can withstand a small bending radius of less than 0.5 mm and have a transparency of up to 96% in all wavelength ranges, owing to the hollowed-out framework structures. Thus, the sc-SiFs provide a new platform for high-performance transparent flexible optoelectronics. Taking transparent flexible photodetectors (TFPDs) as an example, substrate-free and self-driven TFPDs are achieved based on the sc-SiFs. The devices exhibit superior performance compared to other reported TFPDs and reveal the great potential for integrated optoelectronic applications. The development of sc-SiFs paves the way toward the fabrication of high-performance transparent flexible devices for a host of applications, including e-skins, the Internet of Things, transparent flexible displays, and artificial visual cortexes.

10.
BMC Genomics ; 22(1): 350, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33992092

RESUMO

BACKGROUND: The serine carboxypeptidase-like protein (SCPL) family plays a vital role in stress response, growth, development and pathogen defense. However, the identification and functional analysis of SCPL gene family members have not yet been performed in wheat. RESULTS: In this study, we identified a total of 210 candidate genes encoding SCPL proteins in wheat. According to their structural characteristics, it is possible to divide these members into three subfamilies: CPI, CPII and CPIII. We uncovered a total of 209 TaSCPL genes unevenly distributed across 21 wheat chromosomes, of which 65.7% are present in triads. Gene duplication analysis showed that ~ 10.5% and ~ 64.8% of the TaSCPL genes are derived from tandem and segmental duplication events, respectively. Moreover, the Ka/Ks ratios between duplicated TaSCPL gene pairs were lower than 0.6, which suggests the action of strong purifying selection. Gene structure analysis showed that most of the TaSCPL genes contain multiple introns and that the motifs present in each subfamily are relatively conserved. Our analysis on cis-acting elements showed that the promoter sequences of TaSCPL genes are enriched in drought-, ABA- and MeJA-responsive elements. In addition, we studied the expression profiles of TaSCPL genes in different tissues at different developmental stages. We then evaluated the expression levels of four TaSCPL genes by qRT-PCR, and selected TaSCPL184-6D for further downstream analysis. The results showed an enhanced drought and salt tolerance among TaSCPL184-6D transgenic Arabidopsis plants, and that the overexpression of the gene increased proline and decreased malondialdehyde levels, which might help plants adapting to adverse environments. Our results provide comprehensive analyses of wheat SCPL genes that might work as a reference for future studies aimed at improving drought and salt tolerance in wheat. CONCLUSIONS: We conducte a comprehensive bioinformatic analysis of the TaSCPL gene family in wheat, which revealing the potential roles of TaSCPL genes in abiotic stress. Our analysis also provides useful resources for improving the resistance of wheat.


Assuntos
Genoma de Planta , Triticum , Carboxipeptidases , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Triticum/genética
11.
Cell Death Dis ; 12(4): 362, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824276

RESUMO

Adhesion G protein-coupled receptor A1 (ADGRA1, also known as GPR123) belongs to the G protein-coupled receptors (GPCRs) family and is well conserved in the vertebrate lineage. However, the structure of ADGRA1 is unique and its physiological function remains unknown. Previous studies have shown that Adgra1 is predominantly expressed in the central nervous system (CNS), indicating its important role in the transduction of neural signals. The aim of this study is to investigate the central function of Adgra1 in vivo and clarify its physiological significance by establishing an Adgra1-deficient mouse (Adgra1-/-) model. The results show that Adgra1-/- male mice exhibit decreased body weight with normal food intake and locomotion, shrinkage of body mass, increased lipolysis, and hypermetabolic activity. Meanwhile, mutant male mice present elevated core temperature coupled with resistance to hypothermia upon cold stimulus. Further studies show that tyrosine hydroxylase (TH) and ß3-adrenergic receptor (ß3-AR), indicators of sympathetic nerve excitability, are activated as well as their downstream molecules including uncoupling protein 1 (UCP1), coactivator 1 alpha (PGC1-α) in brown adipose tissue (BAT), and hormone-sensitive lipase (HSL) in white adipose tissue (WAT). In addition, mutant male mice have higher levels of serum T3, T4, accompanied by increased mRNAs of hypothalamus-pituitary-thyroid axis. Finally, Adgra1-/- male mice present abnormal activation of PI3K/AKT/GSK3ß and MEK/ERK pathways in hypothalamus. Overexpression of ADGRA1 in Neuro2A cell line appears to suppress these two signaling pathways. In contrast, Adgra1-/- female mice show comparable body weight along with normal metabolic process to their sex-matched controls. Collectively, ADGRA1 is a negative regulator of sympathetic nervous system (SNS) and hypothalamus-pituitary-thyroid axis by regulating PI3K/AKT/GSK3ß and MEK/ERK pathways in hypothalamus of male mice, suggesting an important role of ADGRA1 in maintaining metabolic homeostasis including energy expenditure and thermogenic balance.


Assuntos
Tecido Adiposo Branco/metabolismo , Hipotálamo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Termogênese/fisiologia , Tecido Adiposo Marrom/metabolismo , Animais , Metabolismo Energético/fisiologia , Masculino , Camundongos , Obesidade/metabolismo , Transdução de Sinais/fisiologia , Sistema Nervoso Simpático/metabolismo , Glândula Tireoide/metabolismo
12.
Ying Yong Sheng Tai Xue Bao ; 32(3): 993-1004, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754566

RESUMO

We built a comprehensive evaluation index system of urbanization in Chengdu-Chongqing (Cheng-Yu) urban agglomeration from four subsystems, including the economic, social, ecological, and urban and rural coordination. The comprehensive evaluation index system of eco-environment was constructed by combining ecological environment carrying capacity and ecological flexibi-lity. The coupling coordination degree model was applied to quantify the coupling coordination degree between urbanization and eco-environment in the prefecture-level cities of Cheng-Yu urban agglo-meration from 2005 to 2018. With GIS spatial analysis, phenomenon analysis and Tapio model, we analyzed the interaction type, evolution path and path of decoupling between urbanization and eco-environment in the prefecture-level cities of Cheng-Yu urban agglomeration. The results showed that the urbanization quality of Cheng-Yu urban agglomeration showed a trend of fluctuation and rise during the study period. Both Chengdu and Chongqing as high value areas showed "double-core" radia-ting to the surrounding areas. The eco-environment quality showed a slowly rising trend. The spatial pattern was a " U " shape with a north opening, high perimeter and low center. The degree of coupling coordination between the urbanization system and the eco-environment system was rising, with a spatial pattern of low in the middle and high in the east and west. The overall level of coupling coordination was relatively high. The type of coupling coordination degree was gradually evolving from near-disorder and reluctant coordination to moderate coordination. The evolution paths of urbanization and eco-environmental interaction were divided into two categories: stable and changing. The stable type included 20 cities in 5 subcategories, with Chengdu, Deyang, Mianyang, etc. being always well-coordination. The change type included 16 cities in 9 subcategories. The coordination degree of Chongqing main urban area, Tongliang and most other cities was improved, showing "rising" development. Hechuan, Zigong and a few other cities showed "sinking" development. The growth rates of both ecological environment and urbanization were positive. The decoupling state of urbanization and ecological environment was mainly characterized by weak decoupling and expansion connection.


Assuntos
Conservação dos Recursos Naturais , Urbanização , China , Cidades , Análise Espacial
13.
Front Neuroanat ; 15: 592772, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716679

RESUMO

Background and Aims: Numerous studies have demonstrated thalamus-related structural, functional, and metabolic abnormalities in minimal hepatic encephalopathy (MHE). We conducted the first study to investigate thalamic structural connectivity alterations in MHE. Methods: Diffusion tensor imaging (DTI)-based probabilistic tractography was employed to determine the structural linkage between the thalamus and cortical/subcortical regions in 52 cirrhotic patients [22 with MHE; 30 without MHE (NHE)] and 30 controls. We measured these thalamic connections, which included connectivity strength (CS), fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), and then compared these among the three groups. Neurocognitive assessment was also performed. Correlation analysis was conducted to investigate the relationship between neurocognitive performance and the above measurements. Classification analysis was performed to determine whether thalamic connection measurements can distinguish MHE from NHE. Results: The probabilistic tractography revealed thalamic structural connections, which were disrupted in cirrhotic patients (as reflected by a decrease in CS/FA and an increase in MD/AD/RD). Abnormal thalamic connections primarily involved the prefrontal cortex, sensorimotor cortex, parietal cortex, medial temporal cortex and hippocampus, and striatum. Thalamic connectivity abnormalities deteriorated from NHE to MHE, and they were correlated with patients' neurocognitive performance. The moderate classification accuracy was obtained using CS and MD as discriminating indexes. Conclusion: Our results demonstrated the altered thalamic structural connectivity involving both cortical and subcortical regions in MHE, which could be regarded as representative of MHE-related widespread impairments in white matter pathways. The disturbed thalamic connectivity may underlie the mechanism of cognitive deficits in MHE and may potentially be utilized as a biomarker for diagnosing MHE and in monitoring disease progression. In addition to thalamic-cortical/subcortical connections, further studies are recommended to explore the structural alterations in other white matter pathways in MHE.

14.
Front Plant Sci ; 12: 631470, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763092

RESUMO

Phospholipase C (PLC) performs significant functions in a variety of biological processes, including plant growth and development. The PLC family of enzymes principally catalyze the hydrolysis of phospholipids in organisms. This exhaustive exploration of soybean GmPLC members using genome databases resulted in the identification of 15 phosphatidylinositol-specific PLC (GmPI-PLC) and 9 phosphatidylcholine-hydrolyzing PLC (GmNPC) genes. Chromosomal location analysis indicated that GmPLC genes mapped to 10 of the 20 soybean chromosomes. Phylogenetic relationship analysis revealed that GmPLC genes distributed into two groups in soybean, the PI-PLC and NPC groups. The expression patterns and tissue expression analysis showed that GmPLCs were differentially expressed in response to abiotic stresses. GmPI-PLC7 was selected to further explore the role of PLC in soybean response to drought and salt stresses by a series of experiments. Compared with the transgenic empty vector (EV) control lines, over-expression of GmPI-PLC7 (OE) conferred higher drought and salt tolerance in soybean, while the GmPI-PLC7-RNAi (RNAi) lines exhibited the opposite phenotypes. Plant tissue staining and physiological parameters observed from drought- and salt-stressed plants showed that stress increased the contents of chlorophyll, oxygen free radical (O2 -), hydrogen peroxide (H2O2) and NADH oxidase (NOX) to amounts higher than those observed in non-stressed plants. This study provides new insights in the functional analysis of GmPLC genes in response to abiotic stresses.

15.
PLoS Negl Trop Dis ; 15(3): e0009201, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33725010

RESUMO

BACKGROUND: This study reviews the progress of leprosy elimination in Yunnan, China, over the past 30 years and identifies the challenges for the next stage of the program. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from the Leprosy Management Information System in China (LEPMIS). The progress made in the elimination of leprosy between 1990 and 2019 was measured. We defined two time periods, time period 1 (1990-2003) and time period 2 (2004-2019), because multidrug therapy (MDT) was launched for the treatment of leprosy in 1990 and a special fund from the central government was established for leprosy in 2004. During the past 30 years, the number of newly detected leprosy patients in Yunnan has steadily declined. In total, 703 newly detected leprosy patients were reported in 1990, and 353 and 136 cases were reported at the end of 2003 and 2019, respectively. At the end of 1990, 90.7% (117/129) of counties in Yunnan Province were identified as leprosy-endemic counties (>1 case per 100,000 population). By the end of 2003 and 2019, 39.3% (46/117) and 85.5% (100/117) of the leprosy-endemic counties, respectively, had dropped below the elimination threshold. The main challenges are the remaining leprosy-endemic counties, the high rate of cases with a contact history, insufficient early detection, and leprosy cases resulting in physical disability. CONCLUSIONS/SIGNIFICANCE: A multifaceted strategy for leprosy elimination in Yunnan Province has been successfully implemented, and remarkable progress has been made in the elimination of leprosy in this area. The priorities for leprosy elimination in the next stage are securing sustainable support and investment from the government, establishing an effective surveillance system, ensuring prompt early detection, providing treatment with MDT, preventing transmission of M. leprae, preventing disability, providing health education, and preventing recurrence of the epidemic situation of leprosy.


Assuntos
Erradicação de Doenças , Hanseníase/epidemiologia , Hanseníase/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fatores de Tempo , Adulto Jovem
16.
J Magn Reson Imaging ; 54(1): 239-248, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33559360

RESUMO

BACKGROUND: Aberrant static functional connectivity (FC) has been well demonstrated in amyotrophic lateral sclerosis (ALS); however, ALS-related alterations in FC dynamic properties remain unclear, although dynamic FC analyses contribute to uncover mechanisms underlying neurodegenerative disorders. PURPOSE: To explore dynamic functional network connectivity (dFNC) in ALS and its correlation with disease severity. STUDY TYPE: Prospective. SUBJECTS: Thirty-two ALS patients and 45 healthy controls. FIELD STRENGTH/SEQUENCE: Multiband resting-state functional images using gradient echo echo-planar imaging and T1-weighted images were acquired at 3.0 T. ASSESSMENT: Disease severity was evaluated with the revised ALS Functional Rating Scale (ALSFRS-R) and patients were stratified according to diagnostic category. Independent component analysis was conducted to identify the components of seven intrinsic brain networks (ie, visual/sensorimotor (SMN)/auditory/cognitive-control (CCN)/default-mode (DMN)/subcortical/cerebellar networks). A sliding-window correlation approach was used to compute dFNC. FNC states were determined by k-mean clustering, and state-specific FNC and dynamic indices (fraction time/mean dwell time/transition number) were calculated. STATISTICAL TESTS: Two-sample t test used for comparisons on dynamic measures and Spearman's correlation analysis. RESULTS: ALS patients showed increased FNC between DMN-SMN in state 1 and between CCN-SMN in state 4. Patients remained in state 2 (showing the weakest FNC) for a significantly longer time (mean dwell time: 49.8 ± 40.1 vs. 93.6 ± 126.3; P < 0.05) and remained in state 1 (showing a relatively strong FNC) for a shorter time (fraction time: 0.27 ± 0.25 vs. 0.13 ± 0.20; P < 0.05). ALS patients exhibited less temporal variability in their FNC (transition number: 10.2 ± 4.4 vs. 7.8 ± 3.8; P < 0.05). A significant correlation was observed between ALSFRS-R and mean dwell time in state 2 (r = -0.414, P < 0.05) and transition number (r = 0.452, P < 0.05). No significant between-subgroup difference in dFNC properties was found (all P > 0.05). DATA CONCLUSION: Our findings suggest aberrant dFNC properties in ALS, which is associated with disease severity. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.


Assuntos
Esclerose Amiotrófica Lateral , Mapeamento Encefálico , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estudos Prospectivos , Índice de Gravidade de Doença
17.
Am J Hematol ; 96(5): 561-570, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33606900

RESUMO

Globally, postpartum hemorrhage (PPH) is the leading cause of maternal death. Women with immune thrombocytopenia (ITP) are at increased risk of developing PPH. Early identification of PPH helps to prevent adverse outcomes, but is underused because clinicians do not have a tool to predict PPH for women with ITP. We therefore conducted a nationwide multicenter retrospective study to develop and validate a prediction model of PPH in patients with ITP. We included 432 pregnant women (677 pregnancies) with primary ITP from 18 academic tertiary centers in China from January 2008 to August 2018. A total of 157 (23.2%) pregnancies experienced PPH. The derivation cohort included 450 pregnancies. For the validation cohort, we included 117 pregnancies in the temporal validation cohort and 110 pregnancies in the geographical validation cohort. We assessed 25 clinical parameters as candidate predictors and used multivariable logistic regression to develop our prediction model. The final model included seven variables and was named MONITOR (maternal complication, WHO bleeding score, antepartum platelet transfusion, placental abnormalities, platelet count, previous uterine surgery, and primiparity). We established an easy-to-use risk heatmap and risk score of PPH based on the seven risk factors. We externally validated this model using both a temporal validation cohort and a geographical validation cohort. The MONITOR model had an AUC of 0.868 (95% CI 0.828-0.909) in internal validation, 0.869 (95% CI 0.802-0.937) in the temporal validation, and 0.811 (95% CI 0.713-0.908) in the geographical validation. Calibration plots demonstrated good agreement between MONITOR-predicted probability and actual observation in both internal validation and external validation. Therefore, we developed and validated a very accurate prediction model for PPH. We hope that the model will contribute to more precise clinical care, decreased adverse outcomes, and better health care resource allocation.


Assuntos
Hemorragia Pós-Parto/etiologia , Complicações Hematológicas na Gravidez , Púrpura Trombocitopênica Idiopática/complicações , Adulto , Área Sob a Curva , China/epidemiologia , Estudos de Coortes , Suscetibilidade a Doenças , Registros Eletrônicos de Saúde , Feminino , Seguimentos , Previsões , Geografia Médica , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Recém-Nascido , Modelos Logísticos , Modelos Teóricos , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/prevenção & controle , Prednisona/uso terapêutico , Gravidez , Resultado da Gravidez , Prognóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/terapia , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária/estatística & dados numéricos
18.
Angew Chem Int Ed Engl ; 60(5): 2478-2484, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080106

RESUMO

Developing red thermally activated delayed fluorescence (TADF) emitters for high-performance OLEDs is still facing great challenge. Herein, three red TADF emitters, pDBBPZ-DPXZ, pDTBPZ-DPXZ, and oDTBPZ-DPXZ, are designed and synthesized with same donor-acceptor (D-A) backbone with different peripheral groups attaching on the A moieties. Their lowest triplet states change from locally excited to charge transfer character leading to significantly enhance reverse intersystem crossing process. In particular, oDTBPZ-DPXZ exhibits efficient TADF feature and exciton utilization. It not only achieves an external quantum efficiency (EQE) of 20.1 % in red vacuum-processed OLED, but also realize a high EQE of 18.5 % in a solution-processed OLED, which is among the best results in solution-processed red TADF OLEDs. This work provides an effective strategy for designing red TADF molecules by managing energy level alignments to facilitate the up-conversion process and thus enhance exciton harvesting.

19.
J Org Chem ; 86(1): 632-642, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33252231

RESUMO

A general method for the synthesis of isoselenazoles and isothiazoles has been developed by the base-promoted demethoxylative cycloaddition of alkynyl oxime ethers using the cheap and inactive Se powder and Na2S as selenium and sulfur sources. This transformation features the direct construction of N-, Se-, and S-containing heterocycles through the formation of N-Se/S and C-Se/S bonds in one-pot reactions with excellent functional group tolerance.

20.
Appl Math Model ; 91: 749-767, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33052167

RESUMO

In this paper, a stochastic and a deterministic SIS epidemic model with isolation and varying total population size are proposed. For the deterministic model, we establish the threshold R 0. When R 0 is less than 1, the disease-free equilibrium is globally stable, which means the disease will die out. While R 0 is greater than 1, the endemic equilibrium is globally stable, which implies that the disease will spread. Moreover, there is a critical isolation rate δ*, when the isolation rate is greater than it, the disease will be eliminated. For the stochastic model, we also present its threshold R 0s . When R 0s is less than 1, the disease will disappear with probability one. While R 0s is greater than 1, the disease will persist. We find that stochastic perturbation of the transmission rate (or the valid contact coefficient) can help to reduce the spread of the disease. That is, compared with stochastic model, the deterministic epidemic model overestimates the spread capacity of disease. We further find that there exists a critical the stochastic perturbation intensity of the transmission rate σ*, when the stochastic perturbation intensity of the transmission rate is bigger than it, the disease will disappear. At last, we apply our theories to a realistic disease, pneumococcus amongst homosexuals, carry out numerical simulations and obtain the empirical probability density under different parameter values. The critical isolation rate δ* is presented. When the isolation rate δ is greater than δ*, the pneumococcus amongst will be eliminated.

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