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1.
EMBO J ; 42(9): e111762, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36943004

RESUMEN

Senescence and altered differentiation potential of bone marrow stromal cells (BMSCs) lead to age-related bone loss. As an important posttranscriptional regulatory pathway, alternative splicing (AS) regulates the diversity of gene expression and has been linked to induction of cellular senescence. However, the role of splicing factors in BMSCs during aging remains poorly defined. Herein, we found that the expression of the splicing factor Y-box binding protein 1 (YBX1) in BMSCs decreased with aging in mice and humans. YBX1 deficiency resulted in mis-splicing in genes linked to BMSC osteogenic differentiation and senescence, such as Fn1, Nrp2, Sirt2, Sp7, and Spp1, thus contributing to BMSC senescence and differentiation shift during aging. Deletion of Ybx1 in BMSCs accelerated bone loss in mice, while its overexpression stimulated bone formation. Finally, we identified a small compound, sciadopitysin, which attenuated the degradation of YBX1 and bone loss in old mice. Our study demonstrated that YBX1 governs cell fate of BMSCs via fine control of RNA splicing and provides a potential therapeutic target for age-related osteoporosis.


Asunto(s)
Células Madre Mesenquimatosas , Osteoporosis , Humanos , Ratones , Animales , Osteogénesis/genética , Envejecimiento/metabolismo , Senescencia Celular , Diferenciación Celular/genética , Osteoporosis/metabolismo , Células de la Médula Ósea , Proteína 1 de Unión a la Caja Y/metabolismo
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388681

RESUMEN

MOTIVATION: Cell-type annotation of single-cell RNA-sequencing (scRNA-seq) data is a hallmark of biomedical research and clinical application. Current annotation tools usually assume the simultaneous acquisition of well-annotated data, but without the ability to expand knowledge from new data. Yet, such tools are inconsistent with the continuous emergence of scRNA-seq data, calling for a continuous cell-type annotation model. In addition, by their powerful ability of information integration and model interpretability, transformer-based pre-trained language models have led to breakthroughs in single-cell biology research. Therefore, the systematic combining of continual learning and pre-trained language models for cell-type annotation tasks is inevitable. RESULTS: We herein propose a universal cell-type annotation tool, called CANAL, that continuously fine-tunes a pre-trained language model trained on a large amount of unlabeled scRNA-seq data, as new well-labeled data emerges. CANAL essentially alleviates the dilemma of catastrophic forgetting, both in terms of model inputs and outputs. For model inputs, we introduce an experience replay schema that repeatedly reviews previous vital examples in current training stages. This is achieved through a dynamic example bank with a fixed buffer size. The example bank is class-balanced and proficient in retaining cell-type-specific information, particularly facilitating the consolidation of patterns associated with rare cell types. For model outputs, we utilize representation knowledge distillation to regularize the divergence between previous and current models, resulting in the preservation of knowledge learned from past training stages. Moreover, our universal annotation framework considers the inclusion of new cell types throughout the fine-tuning and testing stages. We can continuously expand the cell-type annotation library by absorbing new cell types from newly arrived, well-annotated training datasets, as well as automatically identify novel cells in unlabeled datasets. Comprehensive experiments with data streams under various biological scenarios demonstrate the versatility and high model interpretability of CANAL. AVAILABILITY: An implementation of CANAL is available from https://github.com/aster-ww/CANAL-torch. CONTACT: dengmh@pku.edu.cn. SUPPLEMENTARY INFORMATION: Supplementary data are available at Journal Name online.


Asunto(s)
Perfilación de la Expresión Génica , Programas Informáticos , Perfilación de la Expresión Génica/métodos , Análisis de Expresión Génica de una Sola Célula , Análisis de la Célula Individual/métodos , Lenguaje , Análisis de Secuencia de ARN/métodos
3.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38279647

RESUMEN

MOTIVATION: The rapid development of spatial transcriptome technologies has enabled researchers to acquire single-cell-level spatial data at an affordable price. However, computational analysis tools, such as annotation tools, tailored for these data are still lacking. Recently, many computational frameworks have emerged to integrate single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics datasets. While some frameworks can utilize well-annotated scRNA-seq data to annotate spatial expression patterns, they overlook critical aspects. First, existing tools do not explicitly consider cell type mapping when aligning the two modalities. Second, current frameworks lack the capability to detect novel cells, which remains a key interest for biologists. RESULTS: To address these problems, we propose an annotation method for spatial transcriptome data called SPANN. The main tasks of SPANN are to transfer cell-type labels from well-annotated scRNA-seq data to newly generated single-cell resolution spatial transcriptome data and discover novel cells from spatial data. The major innovations of SPANN come from two aspects: SPANN automatically detects novel cells from unseen cell types while maintaining high annotation accuracy over known cell types. SPANN finds a mapping between spatial transcriptome samples and RNA data prototypes and thus conducts cell-type-level alignment. Comprehensive experiments using datasets from various spatial platforms demonstrate SPANN's capabilities in annotating known cell types and discovering novel cell states within complex tissue contexts. AVAILABILITY: The source code of SPANN can be accessed at https://github.com/ddb-qiwang/SPANN-torch. CONTACT: dengmh@math.pku.edu.cn.


Asunto(s)
Análisis de Expresión Génica de una Sola Célula , Transcriptoma , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Perfilación de la Expresión Génica/métodos , Programas Informáticos
4.
J Immunol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248600

RESUMEN

We developed a linear amplification-mediated high-throughput genome-wide translocation sequencing method to profile Ig class-switch recombination (CSR) in human B cells in an unbiased and quantitative manner. This enables us to characterize CSR junctions resulting from either deletional recombination or inversion for each Ig class/subclass. Our data showed that more than 90% of CSR junctions detected in peripheral blood in healthy control subjects were due to deletional recombination. We further identified two major CSR junction signatures/patterns in human B cells. Signature 1 consists of recombination junctions resulting from both IgG and IgA switching, with a dominance of Sµ-Sγ junctions (72%) and deletional recombination (87%). Signature 2 is contributed mainly by Sµ-Sα junctions (96%), and these junctions were almost all due to deletional recombination (99%) and were characterized by longer microhomologies. CSR junctions identified in healthy individuals can be assigned to both signatures but with a dominance of signature 1, whereas almost all CSR junctions found in patients with defects in DNA-PKcs or Artemis, two classical nonhomologous end joining (c-NHEJ) factors, align with signature 2. Thus, signature 1 may represent c-NHEJ activity during CSR, whereas signature 2 is associated with microhomology-mediated alternative end joining in the absence of the studied c-NHEJ factors. Our findings suggest that in human B cells, the efficiency of the c-NHEJ machinery and the features of switch regions are crucial for the regulation of CSR orientation. Finally, our high-throughput method can also be applied to study the mechanism of rare types of recombination, such as switching to IgD and locus suicide switching.

5.
Plant Physiol ; 194(2): 1120-1138, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37801620

RESUMEN

Salt stress severely damages the growth and yield of crops. Recently, long noncoding RNAs (lncRNAs) were demonstrated to regulate various biological processes and responses to environmental stresses. However, the regulatory mechanisms of lncRNAs in cotton (Gossypium hirsutum) response to salt stress are still poorly understood. Here, we observed that a lncRNA, trans acting of BGLU24 by lncRNA (TRABA), was highly expressed while GhBGLU24-A was weakly expressed in a salt-tolerant cotton accession (DM37) compared to a salt-sensitive accession (TM-1). Using TRABA as an effector and proGhBGLU24-A-driven GUS as a reporter, we showed that TRABA suppressed GhBGLU24-A promoter activity in double transgenic Arabidopsis (Arabidopsis thaliana), which explained why GhBGLU24-A was weakly expressed in the salt-tolerant accession compared to the salt-sensitive accession. GhBGLU24-A encodes an endoplasmic reticulum (ER)-localized ß-glucosidase that responds to salt stress. Further investigation revealed that GhBGLU24-A interacted with RING-type E3 ubiquitin ligase (GhRUBL). Virus-induced gene silencing (VIGS) and transgenic Arabidopsis studies revealed that both GhBGLU24-A and GhRUBL diminish plant tolerance to salt stress and ER stress. Based on its substantial effect on ER-related degradation (ERAD)-associated gene expression, GhBGLU24-A mediates ER stress likely through the ERAD pathway. These findings provide insights into the regulatory role of the lncRNA TRABA in modulating salt and ER stresses in cotton and have potential implications for developing more resilient crops.


Asunto(s)
Arabidopsis , Celulasas , ARN Largo no Codificante , Tolerancia a la Sal/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Gossypium/metabolismo , Arabidopsis/fisiología , Estrés Fisiológico/genética , Celulasas/genética , Celulasas/metabolismo , Celulasas/farmacología , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Proteínas de Plantas/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35027452

RESUMEN

Alzheimer's disease (AD) is characterized by complex, multifactorial neuropathology, suggesting that small molecules targeting multiple neuropathological factors are likely required to successfully impact clinical progression. Acid sphingomyelinase (ASM) activation has been recognized as an important contributor to these neuropathological features in AD, leading to the concept of using ASM inhibitors for the treatment of this disorder. Here we report the identification of KARI 201, a direct ASM inhibitor evaluated for AD treatment. KARI 201 exhibits highly selective inhibition effects on ASM, with excellent pharmacokinetic properties, especially with regard to brain distribution. Unexpectedly, we found another role of KARI 201 as a ghrelin receptor agonist, which also has therapeutic potential for AD treatment. This dual role of KARI 201 in neurons efficiently rescued neuropathological features in AD mice, including amyloid beta deposition, autophagy dysfunction, neuroinflammation, synaptic loss, and decreased hippocampal neurogenesis and synaptic plasticity, leading to an improvement in memory function. Our data highlight the possibility of potential clinical application of KARI 201 as an innovative and multifaceted drug for AD treatment.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Neuropatología/métodos , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Hipocampo/patología , Memoria , Ratones , Plasticidad Neuronal , Neuronas/metabolismo , Receptores de Ghrelina/metabolismo , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo
7.
J Infect Dis ; 230(2): e318-e326, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38421006

RESUMEN

BACKGROUND: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can lead to severe disease with increased morbidity and mortality among certain risk groups. The presence of autoantibodies against type I interferons (aIFN-Abs) is one mechanism that contributes to severe coronavirus disease 2019 (COVID-19). METHODS: This study aimed to investigate the presence of aIFN-Abs in relation to the soluble proteome, circulating immune cell numbers, and cellular phenotypes, as well as development of adaptive immunity. RESULTS: aIFN-Abs were more prevalent in critical compared to severe COVID-19 but largely absent in the other viral and bacterial infections studied here. The antibody and T-cell response to SARS-CoV-2 remained largely unaffected by the presence aIFN-Abs. Similarly, the inflammatory response in COVID-19 was comparable in individuals with and without aIFN-Abs. Instead, presence of aIFN-Abs had an impact on cellular immune system composition and skewing of cellular immune pathways. CONCLUSIONS: Our data suggest that aIFN-Abs do not significantly influence development of adaptive immunity but covary with alterations in immune cell numbers.


Asunto(s)
Autoanticuerpos , COVID-19 , Interferón Tipo I , SARS-CoV-2 , Humanos , COVID-19/inmunología , Interferón Tipo I/inmunología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , SARS-CoV-2/inmunología , Masculino , Femenino , Persona de Mediana Edad , Inmunidad Celular , Adulto , Anciano , Inmunidad Adaptativa/inmunología , Linfocitos T/inmunología , Índice de Severidad de la Enfermedad
8.
Genes Immun ; 25(2): 158-167, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38570727

RESUMEN

In this study, antibody response and a single-cell RNA-seq analysis were conducted on peripheral blood mononuclear cells from five different groups: naïve subjects vaccinated with AZD1222 (AZ) or Ad5-nCoV (Cso), individuals previously infected and later vaccinated (hybrid) with AZD1222 (AZ-hb) or Ad5-nCoV (Cso-hb), and those who were infected and had recovered from COVID-19 (Inf). The results showed that AZ induced more robust neutralizing antibody responses than Cso. The single-cell RNA data revealed a high frequency of memory B cells in the Cso and Cso-hb. In contrast, AZ and AZ-hb groups exhibited the highest proportion of activated naïve B cells expressing CXCR4. Transcriptomic analysis of CD4+ and CD8+ T cells demonstrated a heterogeneous response following vaccination, hybrid immunity, or natural infection. However, a single dose of Ad5-nCoV was sufficient to strongly activate CD4+ T cells (naïve and memory) expressing ANX1 and FOS, similar to the hybrid response observed with AZ. An interesting finding was the robust activation of a subset of CD8+ T cells expressing GZMB, GZMH, and IFNG genes in the Cso-hb group. Our findings suggest that both vaccines effectively stimulated the cellular immune response; however, the Ad5-nCoV induced a more robust CD8+ T-cell response in previously infected individuals.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Linfocitos T CD8-positivos , Adenoviridae/genética , ChAdOx1 nCoV-19 , Leucocitos Mononucleares , Perfilación de la Expresión Génica , Inmunidad Adaptativa , Anticuerpos Neutralizantes/genética , Anticuerpos Antivirales/genética
9.
Small ; 20(33): e2311267, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38534041

RESUMEN

The controllable construction of complex metal-organic coordination polymers (CPs) merits untold scientific and technological potential, yet remains a grand challenge of one-step construction and modulating simultaneously valence states of metals and topological morphology. Here, a thiocyanuric acid (TCA)-triggered strategy is presented to one-step rapid synthesis a double-crystalline Prussian blue analogue hetero-superstructure (PBA-hs) that comprises a Co3[Fe(CN)6]2 cube overcoated with a KCo[Fe(CN)6] shell, followed by eight self-assembled small cubes on vertices. Unlike common directing surfactants, TCA not only acts as a trigger for the fast growth of KCo[Fe(CN)6] on the Co3[Fe(CN)6]2 phase resulting in a PBA-on-PBA hetero-superstructure, but also serves as a flange-like bridge between them. By combining experiments with simulations, a deprotonation-induced electron transfer (DIET) mechanism is proposed for formation of second phase in PBA-hs, differing from thermally and photo-induced electron transfer processes. To prove utility, the calcined PBA-hs exhibits enhanced oxygen evolution reaction performance. This work provides a new method to design of novel CPs for enriching chemistry and material science. This work offers a practical approach to design novel CPs for enriching chemistry and material science.

10.
Langmuir ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264266

RESUMEN

Demolding is a crucial step in nanoimprint lithography (NIL) for successfully transferring template structures onto resist materials. The process, however, is often hindered by the adhesion and friction between the template and resist, leading to inevitable defects on the replicas and posing challenges in replicating templates with high-aspect-ratio (HAR) structures. Here, we introduce a novel approach using the dissolvable template method to achieve the nondestructive demolding of structure-designable HAR nanoimprint templates. The templates were fabricated by the 3D lithography technology, employing a positive photoresist that can be easily dissolved in alkaline solutions after exposure to ultraviolet (UV) radiation. By implementing this method, we successfully transferred dense arrays of pillars with a minimal diameter of 1.2 µm and a significant aspect ratio of 18, as well as a microlens array diffuser with randomly distributed structural parameters. The dissolvable template method paves the way for stress-free demolding, broadening NIL's application range.

11.
Nanotechnology ; 35(19)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38330450

RESUMEN

Photocatalytic reduction of carbon dioxide is a technology that effectively utilizes CO2and solar energy. Sodium niobate (NaNbO3) has received much attention in the field of photocatalysis due to its excellent photocatalytic properties. However, the application of NaNbO3in the field of photocatalysis is still limited by poor reaction to visible light and easy recombination of photo-generated carriers. Heterojunction with g-C3N4to construct core-shell structure can effectively improve the above problems. Combining the two can design a core-shell composite material that is beneficial for photocatalytic reduction of CO2. Herein, we prepared a core-shell heterojunction g-C3N4/NaNbO3by uniformly impregnating urea on the surface of NaNbO3chromium nanofibers with NaNbO3nanofibers prepared by electrospinning as a catalyst carrier, and urea as a precursor of g-C3N4. The core-shell structure of g-C3N4/NaNbO3was verified by a series of characterization methods such as XPS, XRD, and TEM. It was found that under the same conditions, the methanol yield of core-shell g-C3N4/NaNbO3was 12.86µmol·g-1·h-1, which is twice that of pure NaNbO3(6.67µmol·g-1·h-1). This article highlights an impregnation method to build core-shell structures for improved photocatalytic reduction of CO2.

12.
Acta Pharmacol Sin ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160244

RESUMEN

Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease characterized by unremitting pulmonary myofibroblasts activation, extracellular matrix (ECM) deposition and inflammatory recruitment. PF has no curable medication yet. In this study we investigated the molecular pathogenesis and potential therapeutic targets of PF and discovered drug lead compounds for PF therapy. A murine PF model was established in mice by intratracheal instillation of bleomycin (BLM, 5 mg/kg). We showed that the protein level of pulmonary protein phosphatase magnesium-dependent 1A (PPM1A, also known as PP2Cα) was significantly downregulated in PF patients and BLM-induced PF mice. We demonstrated that TRIM47 promoted ubiquitination and decreased PPM1A protein in PF progression. By screening the lab in-house compound library, we discovered otilonium bromide (OB, clinically used for treating irritable bowel syndrome) as a PPM1A enzymatic activator with an EC50 value of 4.23 µM. Treatment with OB (2.5, 5 mg·kg-1·d-1, i.p., for 20 days) significantly ameliorated PF-like pathology in mice. We constructed PF mice with PPM1A-specific knockdown in the lung tissues, and determined that by targeting PPM1A, OB treatment suppressed ECM deposition through TGF-ß/SMAD3 pathway in fibroblasts, repressed inflammatory responses through NF-κB/NLRP3 pathway in alveolar epithelial cells, and blunted the crosstalk between inflammation in alveolar epithelial cells and ECM deposition in fibroblasts. Together, our results demonstrate that pulmonary PPM1A activation is a promising therapeutic strategy for PF and highlighted the potential of OB in the treatment of the disease.

13.
J Math Biol ; 88(6): 72, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678110

RESUMEN

In this work, we formulate a random Wolbachia invasion model incorporating the effects of imperfect maternal transmission and incomplete cytoplasmic incompatibility (CI). Under constant environments, we obtain the following results: Firstly, the complete invasion equilibrium of Wolbachia does not exist, and thus the population replacement is not achievable in the case of imperfect maternal transmission; Secondly, imperfect maternal transmission or incomplete CI may obliterate bistability and backward bifurcation, which leads to the failure of Wolbachia invasion, no matter how many infected mosquitoes would be released; Thirdly, the threshold number of the infected mosquitoes to be released would increase with the decrease of the maternal transmission rate or the intensity of CI effect. In random environments, we investigate in detail the Wolbachia invasion dynamics of the random mosquito population model and establish the initial release threshold of infected mosquitoes for successful invasion of Wolbachia into the wild mosquito population. In particular, the existence and stability of invariant probability measures for the establishment and extinction of Wolbachia are determined.


Asunto(s)
Conceptos Matemáticos , Modelos Biológicos , Mosquitos Vectores , Wolbachia , Wolbachia/fisiología , Wolbachia/patogenicidad , Animales , Femenino , Mosquitos Vectores/microbiología , Dinámica Poblacional/estadística & datos numéricos , Citoplasma/microbiología , Culicidae/microbiología , Masculino , Simulación por Computador , Herencia Materna
14.
Skin Res Technol ; 30(8): e70004, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39177365

RESUMEN

BACKGROUND: Hair loss profoundly affects women's physical appearance and psychological health. Platelet-rich plasma (PRP) therapy has gained attention as a potential treatment for female hair loss. This systematic review and meta-analysis aim to evaluate the efficacy and safety of PRP in treating different forms of female hair loss. METHODS: A comprehensive search was conducted across PubMed, EMBASE, Scopus, Cochrane Library, Web of Science, and ClinicalTrials.gov from January 2000 to May 2024. The focus was on randomized controlled trials investigating PRP treatment for various types of hair loss in women. The research protocol is registered with International Prospective Register of Systematic Reviews (CRD42024556190). The quality of the studies was evaluated using the Cochrane risk of bias tool (RoB 2). RESULTS: A total of 21 studies comprising 628 participants were included in the analysis. PRP treatment was found to significantly enhance hair density and thickness. Additionally, there was a significant reduction in the number of hairs pulled in the PRP group. Adverse effects were generally mild and transient, with no notable difference in pain or discomfort between the PRP and control groups (risk ratio: 1.01; 95% CI: 0.87-1.18). CONCLUSION: PRP therapy effectively enhances hair density and thickness in women with hair loss, with a favorable safety profile. However, the effects of PRP on hair density and thickness vary with dosage, injection duration, and ethnicity, indicating the need for tailored treatment protocols.


Asunto(s)
Alopecia , Plasma Rico en Plaquetas , Femenino , Humanos , Alopecia/terapia , Cabello , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
15.
BMC Geriatr ; 24(1): 466, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807058

RESUMEN

BACKGROUND: With the aging population, the number of individuals with dementia in China is increasing rapidly. This community-based study aimed to investigate the prevalence and risk factors for dementia and mild cognitive impairment (MCI) among older adults in China. METHODS: In this study, 20,070 individuals aged ≥ 65 were recruited between January 1, 2022, and February 1, 2023, from ten communities in Xiamen City, China. We collected data on age, sex, level of education, and medical history, as well as global cognition and functional status. The prevalence of dementia and MCI was examined, and the risk factors for different groups were assessed. RESULTS: The overall prevalence of dementia and MCI was approximately 5.4% (95% confidence interval [CI], 5.1-5.7) and 7.7% (95% CI, 7.4-8.1), respectively. The results also indicated that dementia and MCI share similar risk factors, including older age, female sex, hypertension, and diabetes mellitus. Compared with individuals with no formal education, those with > 6 years of education had an odds ratio for MCI of 1.83 (95% CI, 1.49-2.25). We also found that only 5.5% of the positive participants chose to be referred to the hospital for further diagnosis and treatment during follow-up visits. CONCLUSIONS: This study estimated the prevalence and risk factors for dementia and MCI among individuals aged ≥ 65 years in Southeast China. These findings are crucial for preventing and managing dementia and MCI in China.


Asunto(s)
Disfunción Cognitiva , Demencia , Humanos , Masculino , Femenino , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/diagnóstico , Anciano , China/epidemiología , Demencia/epidemiología , Demencia/diagnóstico , Prevalencia , Factores de Riesgo , Anciano de 80 o más Años
16.
Nano Lett ; 23(15): 6839-6844, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37463412

RESUMEN

Longevity of Li ion batteries strongly depends on the interaction of transporting Li ions in electrode crystals with defects. However, detailed interactions between the Li ion flux and structural defects in the host crystal remain obscure due to the transient nature of such interactions. Here, by in situ transmission electron microscopy and density function theory calculations, we reveal how the diffusion pathways and transport kinetics of a Li ion can be affected by planar defects in a tungsten trioxide lattice. We uncover that changes in charge distribution and lattice spacing along the planar defects disrupt the continuity of ion conduction channels and dramatically increase the energy barrier of Li diffusion, thus, arresting Li ions at the defect sites and twisting the lithiation front. The atomic-scale understanding holds critical implications for rational interface design in solid-state batteries and solid oxide fuel cells.

17.
J Environ Manage ; 359: 121069, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38714034

RESUMEN

The traditional classification of drought events into seasonal and flash types oversimplified the complexity and variability of global drought phenomena, limiting a deeper understanding of drought characteristics and their impacts on vegetation. To address this issue, soil moisture percentile methods and the Soil Moisture Anomaly Percentage Index (SMAPI) were employed to create time series for flash drought (FD) and seasonal drought (SD) events globally from 1981 to 2020. A novel categorization framework was proposed to subdivide the two basic drought categories into eight distinct drought types using a set relationship identification method. The results showed fluctuating trends in the frequencies of Independent FD and Inclusion FD, which declined rapidly after 2011 at rates of 0.05 and 0.04 times/year, respectively. Independent FD frequency was highest in humid areas and decreased with increasing aridity. The spatial distributions of Inclusion FD and SD were similar, with both frequencies highest in extremely arid areas and decreasing with increasing humidity. The frequency of Independent SD, which peaked in semi-arid areas, increased significantly after 2011 at a rate of 0.01 times/year. The occurrence of FD evolving into SD or emerging at the end of SD was rare, with a global average of 0.46 events/decade and little spatial variation. Between 1981 and 2020, FD showed a U-shaped trend in drought duration, while SD showed no clear pattern. The duration of FD showed little difference across arid and humid zones, but the duration of SD decreased significantly with increasing humidity. Vegetation responses to drought varied, with arid regions showing longer response time compared to humid regions. A positive correlation between temperature and solar-induced chlorophyll fluorescence (SIF) during droughts was observed, while precipitation generally showed a negative correlation with SIF. Radiation had a minimal effect on SIF during droughts. The study offered a comprehensive categorization of drought events, enhancing our understanding of their spatiotemporal characteristics and vegetation responses on a global scale.


Asunto(s)
Sequías , Estaciones del Año , Suelo , Plantas
18.
Molecules ; 29(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38893540

RESUMEN

The direct hydrogenation of greenhouse gas CO2 to higher alcohols (C2+OH) provides a new route for the production of high-value chemicals. Due to the difficulty of C-C coupling, the formation of higher alcohols is more difficult compared to that of other compounds. In this review, we summarize recent advances in the development of multifunctional catalysts, including noble metal catalysts, Co-based catalysts, Cu-based catalysts, Fe-based catalysts, and tandem catalysts for the direct hydrogenation of CO2 to higher alcohols. Possible reaction mechanisms are discussed based on the structure-activity relationship of the catalysts. The reaction-coupling strategy holds great potential to regulate the reaction network. The effects of the reaction conditions on CO2 hydrogenation are also analyzed. Finally, we discuss the challenges and potential opportunities for the further development of direct CO2 hydrogenation to higher alcohols.

19.
Am J Occup Ther ; 78(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38215306

RESUMEN

IMPORTANCE: Establishing empirical evidence on the psychometric properties of the Test of Visual-Motor Skills (3rd ed.; TVMS-3) is helpful for guiding its use as an assessment of visual-motor integration (VMI) skills in kindergarten children with developmental coordination disorder (DCD). OBJECTIVE: To investigate the test-retest reliability, criterion-related validity, and ecological validity of the TVMS-3 in Taiwanese kindergarten children with DCD. DESIGN: A nonexperimental, descriptive, correlational design. SETTING: A hospital in Central Taiwan. PARTICIPANTS: Fifty-seven kindergarten children with DCD were recruited in the study. OUTCOMES AND MEASURES: Intraclass correlation coefficient, percentage of minimal detectable change, and paired t test (Wilcoxon signed rank test) were used to investigate the test-retest reliability of the TVMS-3. The correlations (Pearson's r) between the TVMS-3 accuracy score and the scores of each of the four domains and the adaptive behavior composite score of the Vineland Adaptive Behavior Scales (3rd ed.; Vineland-3) were calculated, respectively, to examine criterion-related validity and ecological validity. RESULTS: The accuracy score of the TVMS-3 had excellent test-retest reliability and acceptable random measurement error. Moreover, it showed good criterion-related validity and sufficient ecological validity with the Vineland-3 in Taiwanese kindergarten children with DCD. CONCLUSIONS AND RELEVANCE: The accuracy score of the TVMS-3 is applicable to Taiwanese kindergarten children with DCD in clinical and research settings. Plain-Language Summary: The accuracy score of the Test of Visual-Motor Skills (3rd ed.; TVMS-3) is a useful assessment tool to detect deficits in visual-motor integration for Taiwanese kindergarten children with developmental coordination disorder. The TVMS-3 has excellent test-retest reliability, good criterion-related validity, and sufficient ecological validity.


Asunto(s)
Trastornos de la Destreza Motora , Destreza Motora , Niño , Humanos , Trastornos de la Destreza Motora/diagnóstico , Reproducibilidad de los Resultados , Escolaridad , Instituciones Académicas , Psicometría
20.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1260-1265, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621973

RESUMEN

A variety of compounds in Artemisia annua were simultaneously determined to evaluate the quality of A. annua from multiple perspectives. A method based on ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS) was established for the simultaneous determination of seven compounds: amorpha-4,11-diene, artemisinic aldehyde, dihydroartemisinic acid, artemisinic acid, artemisinin B, artemisitene, and artemisinin, in A. annua. The content of the seven compounds in different tissues(roots, stems, leaves, and lateral branches) of A. annua were compared. The roots, stems, leaves, and lateral branches of four-month-old A. annua were collected and the content of seven artemisinin-related compounds in different tissues was determined. A multi-reaction monitoring(MRM) acquisition mode of UPLC-QQQ-MS/MS was used, with a positive ion mode of atmospheric pressure chemical ion source(APCI). Chromatographic separation was achieved on an Eclipse Plus RRHD C_(18) column(2.1 mm×50 mm, 1.8 µm). The gradient elution was performed with the mobile phase consisted of formic acid(0.1%)-ammonium formate(5 mmol·L~(-1))(A) and the methanol(B) gradient program of 0-8 min, 55%-100% B, 8-11 min, 100% B, and equilibrium for 3 min, the flow rate of 0.6 mL·min~(-1), the column temperature of 40 ℃, the injection volume of 5 µL, and the detection time of 8 min. Through methodological investigation, a method based on UPLC-QQQ-MS/MS was established for the simultaneous quantitative determination of seven representative compounds involved in the biosynthesis of artemisinin. The content of artemisinin in A. annua was higher than that of artemisinin B, and the content of artemisinin and dihydroartemisinic acid were high in all the tissues of A. annua. The content of the seven compounds varied considerably in different tissues, with the highest levels in the leaves and neither artemisinene nor artemisinic aldehyde was detected in the roots. In this study, a quantitative method based on UPLC-QQQ-MS/MS for the simultaneous determination of seven representative compounds involved in the biosynthesis of artemisinin was established, which was accurate, sensitive, and highly efficient, and can be used for determining the content of artemisinin-related compounds in A. annua, breeding new varieties, and controlling the quality of Chinese medicinal materials.


Asunto(s)
Artemisia annua , Artemisininas , Lactonas , Artemisia annua/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Fitomejoramiento , Artemisininas/análisis , Aldehídos
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