Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 325
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; : e2312098, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461523

RESUMEN

Double-borylated multiple-resonance (MR) skeletons are promising templates for high performance, while the chemical design space is relatively limited. Peripheral segments are often used to decorate/fuse MR skeletons and modulate the photophysics but they can also cause unwanted spectral broadening. Herein, a narrowband MR emitter ICzDBA by fusing an MR-featured donor segment indolocarbazole into a double-borylated MR skeleton is developed. In ICzDBA, the nitrogen atom located away from the core benzene ring can also contribute to the generation of the overall MR-featured distribution through the long-range conjugation effect, along with the other boron/nitrogen atoms on the phenyl center. Thus, ICzDBA in toluene displays a narrowband emission peaking at 507 nm with a full width at half maximum of merely 20 nm (0.09 eV). Moreover, organic light-emitting diode devices using ICzDBA emitter exhibit ultrapure green emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.27, 0.70) and a high external quantum efficiency of 32.5%. These results manifest the importance of MR characters of peripheral decorations/fusions in preserving the narrowband features of MR skeletons, which provides a solution for further expanding MR structures with well-maintained narrowband characters.

2.
J Org Chem ; 89(4): 2351-2363, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38301039

RESUMEN

An effective and stereoselective synthesis of halogenated (E)-4-methylenechromanes with a sulfonyl group was developed via the copper-catalyzed sulfonylative annulation/halogenation of 1,7-enynes, in which sodium sulfinates were used as the sulfonyl reagents and tetrabutylammonium halide provided the halogen sources. The formed alkenyl C-X bonds were valuable and can efficiently undergo the subsequent hydrolysis, alkenylation, alkynylation, arylation, alkylthiolation, and alkoxylation to furnish a series of highly functionalized 4-methylenechromanes.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38547523

RESUMEN

ABSTRACT: Sepsis-induced myocardial dysfunction (SIMD) commonly occurs in individuals with sepsis and is a severe complication with high morbidity and mortality rates. The current study aimed to investigate the effects and potential mechanisms of the natural steroidal sapogenin ruscogenin (RUS) against lipopolysaccharide (LPS)-induced myocardial injury in septic mice. We found that RUS effectively alleviated myocardial pathological damage, normalized cardiac function, and increased survival in septic mice. RNA sequencing (RNA-seq) demonstrated that RUS administration significantly inhibited the activation of the NOD-like receptor signaling pathway in the myocardial tissues of septic mice. Subsequent experiments further confirmed that RUS suppressed myocardial inflammation and pyroptosis during sepsis. Additionally, cultured HL-1 cardiomyocytes were challenged with LPS, and we observed that RUS could protect these cells against LPS-induced cytotoxicity by suppressing inflammation and pyroptosis. Notably, both the in vivo and in vitro findings indicated that RUS inhibited NLRP3 upregulation in cardiomyocytes stimulated with LPS. As expected, knockdown of NLRP3 blocked the LPS-induced activation of inflammation and pyroptosis in HL-1 cells. Furthermore, the cardioprotective effects of RUS on HL-1 cells under LPS stimulation were abolished by the novel NLRP3 agonist BMS-986299. Taken together, our results suggest that RUS can alleviate myocardial injury during sepsis, at least in part by suppressing NLRP3-mediated inflammation and pyroptosis, highlighting the potential of this molecule as a promising candidate for SIMD therapy.

4.
Telemed J E Health ; 30(5): 1425-1435, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38346325

RESUMEN

Background: Children with special health care needs (CSHCN) require long-term and ongoing rehabilitation interventions supporting their development. Telerehabilitation can provide continuous rehabilitation services for CSHCN. However, few studies have explored the intention of CSHCN and their caregivers to use telerehabilitation and its impact on them. Objective: The objective of this study was to identify factors that influence the intention to use telerehabilitation among CSHCN and their caregivers. Methods: This study was a cross-sectional study. Based on the unified theory of acceptance and use of technology, extended with additional predictors (trust and perceived risk [PR]), this study developed a research model and proposed 10 hypotheses. A structured questionnaire was distributed to 176 caregivers. Data were analyzed and research hypotheses were tested using partial least squares structural equation modeling to better understand the factors influencing the use of telerehabilitation. Results: A total of 164 valid questionnaires were collected. CSHCN and their caregivers were overall satisfied with this telerehabilitation medical service. The results of the structural model analysis indicated that social influence (SI), facilitating conditions (FC), and trust had significant effects on behavioral intention (BI) to use telerehabilitation, while the paths between performance expectancy (PE), effort expectancy (EE), and PR and BI were not significant. PE, EE, and SI had a significant effect on trust. Moreover, EE and SI had indirect effects on BI, with trust as the mediator. Conclusions: The results indicated that SI, FC, and trust are significant factors influencing CSHCN and their caregivers' use of telerehabilitation. Trust is also an important mediator for the intention and highly influenced by PE, EE, and SI.


Asunto(s)
Cuidadores , Niños con Discapacidad , Intención , Telerrehabilitación , Humanos , Estudios Transversales , Masculino , Femenino , Telerrehabilitación/métodos , Niño , Niños con Discapacidad/rehabilitación , Cuidadores/psicología , Adolescente , Adulto , Confianza , Preescolar , Encuestas y Cuestionarios , Persona de Mediana Edad
5.
Opt Express ; 31(23): 37763-37777, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-38017899

RESUMEN

In recent years, deep learning (DL) has demonstrated significant potential in the inverse design of metasurfaces, and the generation of metasurfaces with customized transmission characteristics of frequency band remains a challenging and underexplored area. In this study, we propose a DL-assisted method for the inverse design of transmissive metasurfaces. The method consists of a generative adversarial network (GAN)-based graph generator, an electromagnetic response predictor, and a genetic algorithm optimizer. By integrating these components, we can obtain customized metasurfaces with desired transmission characteristics of frequency band. We demonstrate the effectiveness of the proposed method through examples of inverse-designed three-layer cascaded transmissive metasurfaces with wideband, dual-band, and stopband responses in the 8∼12 GHz frequency range. Specifically, we realize three different types of dual-band metasurfaces, namely double-wide, front-wide and rear-narrow, and front-narrow and rear-wide configurations. Additionally, we analyze the accuracy and reliability of the inverse design method by employing data from the training dataset, self-defined objectives, and bandwidth-reduced target responses scaled from the wideband type as design inputs. Quantitative evaluation is performed using metrics such as mean absolute error and average precision. The proposed method successfully achieves the desired effect as intended.

6.
Phys Chem Chem Phys ; 25(4): 2729-2741, 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36633179

RESUMEN

Thermally activated delayed fluorescence (TADF) materials have received enormous attention and the mechanism behind them has been investigated in depth. It has been found that some donor-acceptor (D-A) type TADF emitters could obviously exhibit dual stable conformations in the ground states and their distributions significantly affect the physical properties and device performances. Therefore, professional analysis and a summary of the relationship between molecular structures and performances are very important. In this review, we first summarize the mechanism and properties of TADF emitters with conformational isomerism. We also classify their recent progress according to their different applications, and provide an outlook on their perspectives.

7.
Int J Mol Sci ; 24(8)2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37108500

RESUMEN

In the hexaploid wheat genome, there are three Gα genes, three Gß and twelve Gγ genes, but the function of Gß in wheat has not been explored. In this study, we obtained the overexpression of TaGB1 Arabidopsis plants through inflorescence infection, and the overexpression of wheat lines was obtained by gene bombardment. The results showed that under drought and NaCl treatment, the survival rate of Arabidopsis seedlings' overexpression of TaGB1-B was higher than that of the wild type, while the survival rate of the related mutant agb1-2 was lower than that of the wild type. The survival rate of wheat seedlings with TaGB1-B overexpression was higher than that of the control. In addition, under drought and salt stress, the levels of superoxide dismutase (SOD) and proline (Pro) in the wheat overexpression of TaGB1-B were higher than that of the control, and the concentration of malondialdehyde (MDA) was lower than that of the control. This indicates that TaGB1-B could improve the drought resistance and salt tolerance of Arabidopsis and wheat by scavenging active oxygen. Overall, this work provides a theoretical basis for wheat G-protein ß-subunits in a further study, and new genetic resources for the cultivation of drought-tolerant and salt-tolerant wheat varieties.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Subunidades beta de la Proteína de Unión al GTP , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas Modificadas Genéticamente/genética , Triticum/genética , Triticum/metabolismo , Sequías , Estrés Fisiológico/genética , Plantones/genética , Plantones/metabolismo , Proteínas de Unión al GTP/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Subunidades beta de la Proteína de Unión al GTP/genética
8.
Fa Yi Xue Za Zhi ; 39(2): 115-120, 2023 Apr 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37277373

RESUMEN

OBJECTIVES: To estimate postmortem interval (PMI) by analyzing the protein changes in skeletal muscle tissues with the protein chip technology combined with multivariate analysis methods. METHODS: Rats were sacrificed for cervical dislocation and placed at 16 ℃. Water-soluble proteins in skeletal muscles were extracted at 10 time points (0 d, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, 7 d, 8 d and 9 d) after death. Protein expression profile data with relative molecular mass of 14 000-230 000 were obtained. Principal component analysis (PCA) and orthogonal partial least squares (OPLS) were used for data analysis. Fisher discriminant model and back propagation (BP) neural network model were constructed to classify and preliminarily estimate the PMI. In addition, the protein expression profiles data of human skeletal muscles at different time points after death were collected, and the relationship between them and PMI was analyzed by heat map and cluster analysis. RESULTS: The protein peak of rat skeletal muscle changed with PMI. The result of PCA combined with OPLS discriminant analysis showed statistical significance in groups with different time points (P<0.05) except 6 d, 7 d and 8 d after death. By Fisher discriminant analysis, the accuracy of internal cross-validation was 71.4% and the accuracy of external validation was 66.7%. The BP neural network model classification and preliminary estimation results showed the accuracy of internal cross-validation was 98.2%, and the accuracy of external validation was 95.8%. There was a significant difference in protein expression between 4 d and 25 h after death by the cluster analysis of the human skeletal muscle samples. CONCLUSIONS: The protein chip technology can quickly, accurately and repeatedly obtain water-soluble protein expression profiles in rats' and human skeletal muscles with the relative molecular mass of 14 000-230 000 at different time points postmortem. The establishment of multiple PMI estimation models based on multivariate analysis can provide a new idea and method for PMI estimation.


Asunto(s)
Cambios Post Mortem , Análisis por Matrices de Proteínas , Animales , Humanos , Ratas , Análisis Multivariante , Tecnología
9.
Angew Chem Int Ed Engl ; 62(35): e202305580, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37431732

RESUMEN

Hindered by spectral broadening issues with redshifted emission, long-wavelength (e.g., maxima beyond 570 nm) multiple resonance (MR) emitters with full width at half maxima (FWHMs) below 20 nm remain absent. Herein, by strategically embedding diverse boron (B)/nitrogen (N) atomic pairs into a polycyclic aromatic hydrocarbon (PAH) skeleton, we propose a hybrid pattern for the construction of a long-wavelength narrowband MR emitter. The proof-of-concept emitter B4N6-Me realized orange-red emission with an extremely small FWHM of 19 nm (energy unit: 70 meV), representing the narrowest FWHM among all reported long-wavelength MR emitters. Theoretical calculations revealed that the cooperation of the applied para B-π-N and para B-π-B/N-π-N patterns is complementary, which gives rise to both narrowband and redshift characteristics. The corresponding organic light-emitting diode (OLED) employing B4N6-Me achieved state-of-the-art performance, e.g., a narrowband orange-red emission with an FWHM of 27 nm (energy unit: 99 meV), an excellent maximum external quantum efficiency (EQE) of 35.8 %, and ultralow efficiency roll-off (EQE of 28.4 % at 1000 cd m-2 ). This work provides new insights into the further molecular design and synthesis of long-wavelength MR emitters.

10.
Angew Chem Int Ed Engl ; 62(32): e202306413, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37308770

RESUMEN

Building blocks and heteroatom alignments are two determining factors in designing multiple resonance (MR)-type thermally activated delayed fluorescence (TADF) emitters. Carbazole-fused MR emitters, represented by CzBN derivatives, and the heteroatom alignments of ν-DABNA are two star series of MR-TADF emitters that show impressive performances from the aspects of building blocks and heteroatom alignments, respectively. Herein, a novel CzBN analog, Π-CzBN, featuring ν-DABNA heteroatom alignment is developed via facile one-shot lithium-free borylation. Π-CzBN exhibits superior photophysical properties with a photoluminescence quantum yield close to 100 % and narrowband sky blue emission with a full width at half maximum (FWHM) of 16 nm/85 meV. It also gives efficient TADF properties with a small singlet-triplet energy offset of 40 meV and a fast reverse intersystem crossing rate of 2.9×105  s-1 . The optimized OLED using Π-CzBN as the emitter achieves an exceptional external quantum efficiency of 39.3 % with a low efficiency roll-off of 20 % at 1000 cd m-2 and a narrowband emission at 495 nm with FWHM of 21 nm/106 meV, making it one of the best reported devices based on MR emitters with comprehensive performance.

11.
BMC Genomics ; 23(1): 89, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35100988

RESUMEN

BACKGROUND: Three-amino-loop-extension (TALE) superfamily genes are widely present in plants and function directly in plant growth and development and abiotic stress response. Although TALE genes have been studied in many plant species, members of the TALE family have not been identified in wheat. RESULTS: In this study, we identified 70 wheat TALE protein candidate genes divided into two subfamilies, KNOX (KNOTTED-like homeodomain) and BEL1-like (BLH/BELL homeodomain). Genes in the same subfamily or branch in the phylogenetic tree are similar in structure, and their encoded proteins have similar motifs and conserved structures. Wheat TALE genes are unevenly distributed on 21 chromosomes and expanded on the fourth chromosome. Through gene duplication analysis, 53 pairs of wheat TALE genes were determined to result from segmental duplication events, and five pairs were caused by tandem duplication events. The Ka/Ks between TALE gene pairs indicates a strong purification and selection effect. There are multiple cis-elements in the 2000 bp promoter sequence that respond to hormones and abiotic stress, indicating that most wheat TALE genes are involved in the growth, development, and stress response of wheat. We also studied the expression profiles of wheat TALE genes in different developmental stages and tissues and under different stress treatments. We detected the expression levels of four TALE genes by qRT-PCR, and selected TaKNOX11-A for further downstream analysis. TaKNOX11-A enhanced the drought and salt tolerances of Arabidopsis thaliana. TaKNOX11-A overexpressing plants had decreased malondialdehyde content and increased proline content, allowing for more effective adaptation of plants to unfavorable environments. CONCLUSIONS: We identified TALE superfamily members in wheat and conducted a comprehensive bioinformatics analysis. The discovery of the potential role of TaKNOX11-A in drought resistance and salt tolerance provides a basis for follow-up studies of wheat TALE family members, and also provides new genetic resources for improving the stress resistance of wheat.


Asunto(s)
Proteínas de Plantas , Triticum , Genoma de Planta , Filogenia , Proteínas de Plantas/genética , Estrés Fisiológico/genética , Triticum/genética
12.
Small ; 18(21): e2201548, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35491513

RESUMEN

Adequately harvesting all excitons in a single molecule and inhibiting exciton losses caused by intermolecular interactions are two important factors for achieving high efficiencies thermally activated delayed fluorescence (TADF). One potential approach for optimizing these is to tune alignment of various excited state energy levels by using different doping concentrations. Unfortunately, emission efficiencies of most TADF emitters decrease rapidly with concentrations which limits the window for energy level tunning. In this work, by introducing a spiro group to increase steric hindrance of a TADF emitter (BPPXZ) with a phenoxazine and a dibenzo[a,c]phenazine, emission efficiency of the resulting molecule (BPSPXZ) is much less affected by concentration increase. This enables exploitation of the concentration effects to tune energy levels of its excited states for obtaining simultaneously small singlet-triplet energy offset and large spin-orbital coupling, leading to high-efficiency reverse intersystem crossing. With these merits, organic light-emitting diodes (OLEDs) using the BPSPXZ emitter from 5 to 60 wt% doping can all deliver EQE of over 20%. More importantly, record-high EQEs of 33.4% and 15.8% are respectively achieved in the optimized and nondoped conditions. This work proposes a strategy for developing red TADF emitters by optimizing the intermolecular interaction and energy level alignments to facilitate exciton utilization over wide doping concentrations.

13.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35805912

RESUMEN

The peptidase M24 (Metallopeptidase 24, M24) superfamily is essential for plant growth, stress response, and pathogen defense. At present, there are few systematic reports on the identification and classification of members of the peptidase M24 proteins superfamily in wheat. In this work, we identified 53 putative candidate TaM24 genes. According to the protein sequences characteristics, these members can be roughly divided into three subfamilies: I, II, III. Most TaM24 genes are complex with multiple exons, and the motifs are relatively conserved in each sub-group. Through chromosome mapping analysis, we found that the 53 genes were unevenly distributed on 19 wheat chromosomes (except 3A and 3D), of which 68% were in triads. Analysis of gene duplication events showed that 62% of TaM24 genes in wheat came from fragment duplication events, and there were no tandem duplication events to amplify genes. Analysis of the promoter sequences of TaM24 genes revealed that cis-acting elements were rich in response elements to drought, osmotic stress, ABA, and MeJA. We also studied the expression of TaM24 in wheat tissues at developmental stages and abiotic stress. Then we selected TaM24-9 as the target for further analysis. The results showed that TaM24-9 genes strengthened the drought and salt tolerance of plants. Overall, our analysis showed that members of the peptidase M24 genes may participate in the abiotic stress response and provided potential gene resources for improving wheat resistance.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Triticum , Genoma de Planta , Familia de Multigenes , Péptido Hidrolasas/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Triticum/metabolismo
14.
Angew Chem Int Ed Engl ; 61(47): e202212575, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36167946

RESUMEN

Multiple resonance (MR) type thermally activated delayed fluorescence (TADF) material is currently a research hotspot in organic light-emitting diodes (OLEDs) due to their high color purity and high exciton utilization. However, there are only a handful of MR-TADF emitters with emissions beyond the blue-to-green region. The very limited emission colors for MR-TADF emitters are mainly caused by the fact that so far molecular modifications of MR-TADF do not offer much change in the emission colors. Here, we report a new approach to modifying a prototypical MR core of DABNA by fusing carbazoles to the MR framework. The carbazole-fused molecule (TCZ-F-DABNA) basically maintains the MR-dominated features of DABNA while red-shifting the emission. Its OLED achieves an external quantum efficiency of 39.2 % with a peak at 588 nm, which is a record-high efficiency for OLEDs with peaks beyond 560 nm. This work provides a new approach for significantly tunning emission colors of MR-TADF emitters.

15.
BMC Genomics ; 22(1): 350, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33992092

RESUMEN

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.


Asunto(s)
Genoma de Planta , Triticum , Carboxipeptidasas , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas/genética , Estrés Fisiológico/genética , Triticum/genética
16.
Small ; 17(43): e2103127, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34510742

RESUMEN

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.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Fototerapia , Polímeros , Nanomedicina Teranóstica
17.
J Magn Reson Imaging ; 54(1): 239-248, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33559360

RESUMEN

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.


Asunto(s)
Esclerosis Amiotrófica Lateral , Mapeo Encefálico , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Estudios Prospectivos , Índice de Severidad de la Enfermedad
18.
Am J Hematol ; 96(5): 561-570, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33606900

RESUMEN

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.


Asunto(s)
Hemorragia Posparto/etiología , Complicaciones Hematológicas del Embarazo , Púrpura Trombocitopénica Idiopática/complicaciones , Adulto , Área Bajo la Curva , China/epidemiología , Estudios de Cohortes , Susceptibilidad a Enfermedades , Registros Electrónicos de Salud , Femenino , Estudios de Seguimiento , Predicción , Geografía Médica , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunosupresores/uso terapéutico , Recién Nacido , Modelos Logísticos , Modelos Teóricos , Hemorragia Posparto/epidemiología , Hemorragia Posparto/prevención & control , Prednisona/uso terapéutico , Embarazo , Resultado del Embarazo , Pronóstico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/terapia , Estudios Retrospectivos , Factores de Riesgo , Centros de Atención Terciaria/estadística & datos numéricos
19.
J Org Chem ; 86(1): 632-642, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33252231

RESUMEN

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.
Org Biomol Chem ; 19(46): 10174-10180, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34787150

RESUMEN

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.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA