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1.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712164

RESUMO

The Christchurch mutation (R136S) on the APOE3 (E3S/S) gene is associated with low tau pathology and slowdown of cognitive decline despite the causal PSEN1 mutation and high levels of amyloid beta pathology in the carrier1. However, the molecular effects enabling E3S/S mutation to confer protection remain unclear. Here, we replaced mouse Apoe with wild-type human E3 or E3S/S on a tauopathy background. The R136S mutation markedly mitigated tau load and protected against tau-induced synaptic loss, myelin loss, and spatial learning. Additionally, the R136S mutation reduced microglial interferon response to tau pathology both in vivo and in vitro, suppressing cGAS-STING activation. Treating tauopathy mice carrying wild-type E3 with cGAS inhibitor protected against tau-induced synaptic loss and induced similar transcriptomic alterations to those induced by the R136S mutation across brain cell types. Thus, cGAS-STING-IFN inhibition recapitulates the protective effects of R136S against tauopathy.

2.
Anal Chim Acta ; 1308: 342649, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38740457

RESUMO

BACKGROUND: Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a-powered biosensor with a G-quadruplex (G4) reporter offer the benefits of simplicity and sensitivity, making them extensively utilized in detection applications. However, these biosensors used for monitoring pollutants in environmental water samples may face the problem of high background signal and easy interference due to the "signal-off" output. It is obvious that a biosensor based on the CRISPR/Cas12a system and G4 with a "signal on" output mode needs to be designed for detecting environmental pollutants. RESULTS: By using phosphorothioate-modified G4 as a reporter and catalytic hairpin assembly (CHA) integrated with Cas12a as an amplification strategy, a "signal-on" colorimetric/photothermal biosensor (psG4-CHA/Cas) for portable detection of environmental pollutants was developed. With the help of functional nucleotides, the target pollutant (kanamycin or Pb2+) triggers a CHA reaction to produce numerous double-strand DNA, which can activate Cas12a's trans-cleavage activity. The active Cas12a cleaves locked DNA to release caged psG-rich sequences. Upon binding hemin, the psG-rich sequence forms a psG4/hemin complex, facilitating the oxidation of the colorless 3,3',5,5'-tetramethylbenzidine (TMB) into the blue photothermal agent (oxTMB). The smartphone was employed for portable colorimetric detection of kanamycin and Pb2+. The detection limits were found to be 100 pM for kanamycin and 50 pM for Pb2+. Detection of kanamycin and Pb2+ was also carried out using a portable thermometer with a detection limit of 10 pM for kanamycin and 8 pM for Pb2+. SIGNIFICANCE: Sensitive, selective, simple and robust detection of kanamycin and Pb2+ in environmental water samples is achieved with the psG4-CHA/Cas system. This system not only provides a new perspective on the development of efficient CRISPR/Cas12a-based "signal-on" designs, but also has a promising application for safeguarding human health and environmental monitoring.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Quadruplex G , Técnicas Biossensoriais/métodos , Sistemas CRISPR-Cas/genética , Colorimetria , Chumbo/análise , Poluentes Ambientais/análise , Limite de Detecção , Proteínas Associadas a CRISPR/química , Proteínas Associadas a CRISPR/genética , Poluentes Químicos da Água/análise , Proteínas de Bactérias , Endodesoxirribonucleases
3.
Cell ; 187(10): 2446-2464.e22, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38582079

RESUMO

Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to a lack of appropriate human models. Here, we engineered human induced pluripotent stem cell (hiPSC)-derived neuronal lines to express 4R Tau and 4R Tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes including shared transcriptomic signatures, autophagic body accumulation, and reduced neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of seeding-induced Tau propagation, including retromer VPS29 and genes in the UFMylation cascade. In progressive supranuclear palsy (PSP) and Alzheimer's Disease (AD) brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade in vitro and in vivo suppressed seeding-induced Tau propagation. This model provides a robust platform to identify novel therapeutic strategies for 4R tauopathy.


Assuntos
Células-Tronco Pluripotentes Induzidas , Neurônios , Tauopatias , Proteínas tau , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas tau/metabolismo , Tauopatias/metabolismo , Tauopatias/patologia , Neurônios/metabolismo , Neurônios/patologia , Animais , Camundongos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/genética , Encéfalo/metabolismo , Encéfalo/patologia , Paralisia Supranuclear Progressiva/metabolismo , Paralisia Supranuclear Progressiva/patologia , Paralisia Supranuclear Progressiva/genética , Diferenciação Celular , Mutação , Autofagia
4.
Nanoscale ; 16(16): 8028-8035, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38546273

RESUMO

Two-dimensional (2D) chromium-based self-intercalated materials Cr1+nX2 (0 ≤ n ≤ 1, X = S, Se, Te) have attracted much attention because of their tunable magnetism with good environmental stability. Intriguingly, the magnetic and electrical properties of the materials can be effectively tuned by altering the coverage and spatial arrangement of the intercalated Cr (ic-Cr) within the van der Waals gap, contributing to different stoichiometries. Several different Cr1+nX2 systems have been widely investigated recently; however, those with the same stoichiometric ratio (such as Cr1.25Te2) were reported to exhibit disparate magnetic properties, which still lacks explanation. Therefore, a systematic in situ study of the mechanisms with microscopy techniques is in high demand to look into the origin of these discrepancies. Herein, 2D self-intercalated Cr1+nSe2 nanoflakes were synthesized as a platform to conduct the characterization. Combining scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM), we studied in depth the microscopic structure and local electronic properties of the Cr1+nSe2 nanoflakes. The self-intercalation mechanism of ic-Cr and local stoichiometric-ratio variation in a Cr1+nSe2 ultrathin nanoflake is clearly detected at the nanometer scale. Scanning tunneling spectroscopy (STS) measurements indicate that Cr1.5Se2/Cr2Se2 and Cr1.25Se2 exhibit conductive and semiconductive behaviors, respectively. The STM tip manipulation method is further applied to manipulate the microstructure of Cr1+nSe2, which successfully produces clean zigzag-type boundaries. Our systematic microscopy study paves the way for the in-depth study of the magnetic mechanism of 2D self-intercalated magnets at the nano/micro scale and the development of new magnetic and spintronic devices.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38530719

RESUMO

Weakly supervised temporal action localization (TAL) aims to localize the action instances in untrimmed videos using only video-level action labels. Without snippet-level labels, this task should be hard to distinguish all snippets with accurate action/background categories. The main difficulties are the large variations brought by the unconstraint background snippets and multiple subactions in action snippets. The existing prototype model focuses on describing snippets by covering them with clusters (defined as prototypes). In this work, we argue that the clustered prototype covering snippets with simple variations still suffers from the misclassification of the snippets with large variations. We propose an ensemble prototype network (EPNet), which ensembles prototypes learned with consensus-aware clustering. The network stacks a consensus prototype learning (CPL) module and an ensemble snippet weight learning (ESWL) module as one stage and extends one stage to multiple stages in an ensemble learning way. The CPL module learns the consensus matrix by estimating the similarity of clustering labels between two successive clustering generations. The consensus matrix optimizes the clustering to learn consensus prototypes, which can predict the snippets with consensus labels. The ESWL module estimates the weights of the misclassified snippets using the snippet-level loss. The weights update the posterior probabilities of the snippets in the clustering to learn prototypes in the next stage. We use multiple stages to learn multiple prototypes, which can cover the snippets with large variations for accurate snippet classification. Extensive experiments show that our method achieves the state-of-the-art weakly supervised TAL methods on two benchmark datasets, that is, THUMOS'14, ActivityNet v1.2, and ActivityNet v1.3 datasets.

6.
Chem Commun (Camb) ; 60(27): 3677-3680, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38456735

RESUMO

A strategy for the preparation of hydrogel layer MXene membranes by an F-free method was proposed. It maintained high permeance (2686.1 L m-2 h-1 bar-1) and separation efficiency (99.99%) even after 300 min of emulsion separation. The membrane resisted harsh chemical and microbiological environments and efficiently treated actual oily wastewater.

7.
BMC Genomics ; 25(1): 145, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321406

RESUMO

BACKGROUND: Schizothorax o'connori is an endemic fish distributed in the upper and lower reaches of the Yarlung Zangbo River in China. It has experienced a fourth round of whole gene replication events and is a good model for exploring the genetic differentiation and environmental adaptability of fish in the Qinghai-Tibet Plateau. The uplift of the Qinghai-Tibet Plateau has led to changes in the river system, thereby affecting gene exchange and population differentiation between fish populations. With the release of fish whole genome data, whole genome resequencing has been widely used in genetic evolutionary analysis and screening of selected genes in fish, which can better elucidate the genetic basis and molecular environmental adaptation mechanisms of fish. Therefore, our purpose of this study was to understand the population structure and adaptive characteristics of S. o'connori using the whole-genome resequencing method. RESULTS: The results showed that 23,602,746 SNPs were identified from seven populations, mostly distributed on chromosomes 2 and 23. There was no significant genetic differentiation between the populations, and the genetic diversity was relatively low. However, the Zangga population could be separated from the Bomi, Linzhi, and Milin populations in the cluster analysis. Based on historical dynamics analysis of the population, the size of the ancestral population of S. o'connori was affected by the late accelerated uplift of the Qinghai Tibet Plateau and the Fourth Glacial Age. The selected sites were mostly enriched in pathways related to DNA repair and energy metabolism. CONCLUSION: Overall, the whole-genome resequencing analysis provides valuable insights into the population structure and adaptive characteristics of S. o'connori. There was no obvious genetic differentiation at the genome level between the S. o'connori populations upstream and downstream of the Yarlung Zangbo River. The current distribution pattern and genetic diversity are influenced by the late accelerated uplift of the Qinghai Tibet Plateau and the Fourth Ice Age. The selected sites of S. o'connori are enriched in the energy metabolism and DNA repair pathways to adapt to the low temperature and strong ultraviolet radiation environment at high altitude.


Assuntos
Cyprinidae , Raios Ultravioleta , Animais , Tibet , China , Cyprinidae/genética , Análise de Sequência de DNA
8.
Small ; : e2311336, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385851

RESUMO

The electrocatalytic conversion of nitrate (NO3 - ) to NH3 (NO3 RR) at ambient conditions offers a promising alternative to the Haber-Bosch process. The pivotal factors in optimizing the proficient conversion of NO3 - into NH3 include enhancing the adsorption capabilities of the intermediates on the catalyst surface and expediting the hydrogenation steps. Herein, the Cu/Cu2 O/Pi NWs catalyst is designed based on the directed-evolution strategy to achieve an efficient reduction of NO3 ‾. Benefiting from the synergistic effect of the OV -enriched Cu2 O phase developed during the directed-evolution process and the pristine Cu phase, the catalyst exhibits improved adsorption performance for diverse NO3 RR intermediates. Additionally, the phosphate group anchored on the catalyst's surface during the directed-evolution process facilitates water electrolysis, thereby generating Hads on the catalyst surface and promoting the hydrogenation step of NO3 RR. As a result, the Cu/Cu2 O/Pi NWs catalyst shows an excellent FE for NH3 (96.6%) and super-high NH3 yield rate of 1.2 mol h-1  gcat. -1 in 1 m KOH and 0.1 m KNO3 solution at -0.5 V versus RHE. Moreover, the catalyst's stability is enhanced by the stabilizing influence of the phosphate group on the Cu2 O phase. This work highlights the promise of a directed-evolution approach in designing catalysts for NO3 RR.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38386498

RESUMO

The number of newly reported HIV-1 infections among older individuals (aged ≥50 years) has increased rapidly in Hangzhou, a central city in the Yangtze River Delta region of China. To provide a scientific basis for prevention and intervention strategies targeted at older individuals in Hangzhou, an epidemiological survey combined with molecular transmission network analysis was conducted. A total of 2899 individuals with newly confirmed HIV-1 infections, including 635 older individuals and 2264 younger individuals (aged <50 years), were enrolled in this study. Among older individuals, heterosexual contact was the predominant mode of HIV-1 transmission. Additionally, it was observed that older individuals with lower levels of education exhibited a higher susceptibility to HIV-1 infection. The analysis of transmission network which was inferred using HIV-TRACE algorithm revealed that the newly diagnosed HIV-1 infections among older individuals in Hangzhou exhibited a pattern of scattered transmission, with key clusters primarily located in non-main urban areas. The predominant mode of transmission in these areas was non-marital and non-commercial or non-marital and commercial heterosexual transmission. Notably, the study highlighted a significant proportion of older individuals (73.3%, 11/15) within B subtype. Multivariate logistic regression analysis further revealed that the subtype B was a significant factor associated with older individuals having ≥3 node degrees in the network, occurring 5.55 times more frequent than subtype CRF07_BC (95% CI = 1.17-26.22, p = 0.031). Furthermore, the lower CD4 levels observed among older individuals underscored the challenge of late diagnosis in Hangzhou. Taken together, it is imperative to test and intervene for high-risk older individuals. To tackle this issue effectively, it is essential to enhance the detection of the B subtype and implement targeted interventions in key clusters within non-main urban areas. Additionally, proactive measures should be implemented to address the challenge of late diagnosis in Hangzhou by promoting widespread testing among the older individuals, particularly in priority areas.

10.
bioRxiv ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38328219

RESUMO

The strongest risk factors for Alzheimer's disease (AD) include the χ4 allele of apolipoprotein E (APOE), the R47H variant of triggering receptor expressed on myeloid cells 2 (TREM2), and female sex. Here, we combine APOE4 and TREM2R47H ( R47H ) in female P301S tauopathy mice to identify the pathways activated when AD risk is the strongest, thereby highlighting disease-causing mechanisms. We find that the R47H variant induces neurodegeneration in female APOE4 mice without impacting hippocampal tau load. The combination of APOE4 and R47H amplified tauopathy-induced cell-autonomous microglial cGAS-STING signaling and type-I interferon response, and interferon signaling converged across glial cell types in the hippocampus. APOE4-R47H microglia displayed cGAS- and BAX-dependent upregulation of senescence, showing association between neurotoxic signatures and implicating mitochondrial permeabilization in pathogenesis. By uncovering pathways enhanced by the strongest AD risk factors, our study points to cGAS-STING signaling and associated microglial senescence as potential drivers of AD risk.

11.
PLoS One ; 18(12): e0296309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134210

RESUMO

Since the coronavirus (COVID-19) outbreak in December 2019, students have been under unparalleled psychological stress worldwide. As part of its prevention and control strategies, the Chinese Ministry of Education proposed online teaching activities for universities. For the first time, teaching and learning shifted completely online, significantly impacting university students used to classroom learning. This research addresses the knowledge gap about the mental health and coping strategies employed by Chinese university students during the COVID-19 pandemic. Electronic databases (PsycINFO, Scopus, Medline, Cochranes and CNKI) were searched systematically from 2019 to 2023, as part of this literature review. From the 349 articles found, 25 met the inclusion criteria for analysis. Thematic analysis was used to identify six sub-themes, organized under two main themes: Mental health issues of Chinese university students and their coping mechanisms. Heightened stress, anxiety, and depression appeared in Chinese university students during the pandemic, which may have been compounded by their isolation and the disruptions to their studies. Although the impact of COVID-19 on Chinese university students is waning, this study emphasizes the potential long-lasting impact on their mental health, which requires further investigation, particularly regarding gender differences. Moreover, positive and negative coping strategies were found in this review. Strategies for seeking social and family support and participating in sports activities had significant alleviating effects, while negative coping strategies such as alcohol-use and smoking did not. This rapid review informs the development of policies and interventions to enhance the mental health of university students during crisis events. The findings serve to inform health policymakers, university psychologists, and educators in improving the well-being of this student population.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Pandemias , Capacidades de Enfrentamento , Universidades , SARS-CoV-2 , Estudantes/psicologia , Nível de Saúde
12.
bioRxiv ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37961594

RESUMO

Pathogenic tau accumulation fuels neurodegeneration in Alzheimer's disease (AD). Enhancing aging brain's resilience to tau pathology would lead to novel therapeutic strategies. DAP12 (DNAX-activation protein 12) is critically involved in microglial immune responses. Previous studies have showed that mice lacking DAP12 in tauopathy mice exhibit higher tau pathology but are protected from tau-induced cognitive deficits. However, the exact mechanism remains elusive. Our current study uncovers a novel resilience mechanism via microglial interaction with oligodendrocytes. Despite higher tau inclusions, Dap12 deletion curbs tau-induced brain inflammation and ameliorates myelin and synapse loss. Specifically, removal of Dap12 abolished tau-induced disease-associated clusters in microglia (MG) and intermediate oligodendrocytes (iOli), which are spatially correlated with tau pathology in AD brains. Our study highlights the critical role of interactions between microglia and oligodendrocytes in tau toxicity and DAP12 signaling as a promising target for enhancing resilience in AD.

13.
Res Sq ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37961627

RESUMO

Pathogenic tau accumulation fuels neurodegeneration in Alzheimer's disease (AD). Enhancing aging brain's resilience to tau pathology would lead to novel therapeutic strategies. DAP12 (DNAX-activation protein 12) is critically involved in microglial immune responses. Previous studies have showed that mice lacking DAP12 in tauopathy mice exhibit higher tau pathology but are protected from tau-induced cognitive deficits. However, the exact mechanism remains elusive. Our current study uncovers a novel resilience mechanism via microglial interaction with oligodendrocytes. Despite higher tau inclusions, Dap12 deletion curbs tau-induced brain inflammation and ameliorates myelin and synapse loss. Specifically, removal of Dap12 abolished tau-induced disease-associated clusters in microglia (MG) and intermediate oligodendrocytes (iOli), which are spatially correlated with tau pathology in AD brains. Our study highlights the critical role of interactions between microglia and oligodendrocytes in tau toxicity and DAP12 signaling as a promising target for enhancing resilience in AD.

14.
Mol Neurodegener ; 18(1): 73, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789345

RESUMO

BACKGROUND: Cerebral amyloid angiopathy (CAA) is a devastating condition common in patients with Alzheimer's disease but also observed in the general population. Vascular oxidative stress and neurovascular dysfunction have been implicated in CAA but the cellular source of reactive oxygen species (ROS) and related signaling mechanisms remain unclear. We tested the hypothesis that brain border-associated macrophages (BAM), yolk sac-derived myeloid cells closely apposed to parenchymal and leptomeningeal blood vessels, are the source of radicals through the Aß-binding innate immunity receptor CD36, leading to neurovascular dysfunction, CAA, and cognitive impairment. METHODS: Tg2576 mice and WT littermates were transplanted with CD36-/- or CD36+/+ bone marrow at 12-month of age and tested at 15 months. This approach enables the repopulation of perivascular and leptomeningeal compartments with CD36-/- BAM. Neurovascular function was tested in anesthetized mice equipped with a cranial window in which cerebral blood flow was monitored by laser-Doppler flowmetry. Amyloid pathology and cognitive function were also examined. RESULTS: The increase in blood flow evoked by whisker stimulation (functional hyperemia) or by endothelial and smooth muscle vasoactivity was markedly attenuated in WT → Tg2576 chimeras but was fully restored in CD36-/- → Tg2576 chimeras, in which BAM ROS production was suppressed. CAA-associated Aß1-40, but not Aß1-42, was reduced in CD36-/- → Tg2576 chimeras. Similarly, CAA, but not parenchymal plaques, was reduced in CD36-/- → Tg2576 chimeras. These beneficial vascular effects were associated with cognitive improvement. Finally, CD36-/- mice were able to more efficiently clear exogenous Aß1-40 injected into the neocortex or the striatum. CONCLUSIONS: CD36 deletion in BAM suppresses ROS production and rescues the neurovascular dysfunction and damage induced by Aß. CD36 deletion in BAM also reduced brain Aß1-40 and ameliorated CAA without affecting parenchyma plaques. Lack of CD36 enhanced the vascular clearance of exogenous Aß. Restoration of neurovascular function and attenuation of CAA resulted in a near complete rescue of cognitive function. Collectively, these data implicate brain BAM in the pathogenesis of CAA and raise the possibility that targeting BAM CD36 is beneficial in CAA and other conditions associated with vascular Aß deposition and damage.


Assuntos
Doença de Alzheimer , Angiopatia Amiloide Cerebral , Disfunção Cognitiva , Humanos , Camundongos , Animais , Espécies Reativas de Oxigênio , Camundongos Transgênicos , Angiopatia Amiloide Cerebral/patologia , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/patologia , Encéfalo/patologia , Macrófagos/metabolismo , Estresse Oxidativo , Disfunção Cognitiva/patologia
15.
bioRxiv ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37781600

RESUMO

Demyelination occurs in aging and associated diseases, including Alzheimer's disease. Several of these diseases exhibit sex differences in prevalence and severity. Biological sex primarily stems from sex chromosomes and gonads releasing sex hormones. To dissect mechanisms underlying sex differences in demyelination of aging brains, we constructed a transcriptomic atlas of cell type-specific responses to illustrate how sex chromosomes, gonads, and their interaction shape responses to demyelination. We found that sex-biased oligodendrocyte and microglial responses are driven by interaction of sex chromosomes and gonads prior to myelin loss. Post demyelination, sex chromosomes mainly guide microglial responses, while gonadal composition influences oligodendrocyte signaling. Significantly, ablation of the X-linked gene Toll-like receptor 7 (Tlr7), which exhibited sex-biased expression during demyelination, abolished the sex-biased responses and protected against demyelination.

16.
Adv Sci (Weinh) ; 10(33): e2303789, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37822155

RESUMO

The electrocatalytic conversion of nitrate (NO3 ‾) to NH3  (NO3 RR) offers a promising alternative to the Haber-Bosch process. However, the overall kinetic rate of NO3 RR is plagued by the complex proton-assisted multiple-electron transfer process. Herein, Ag/Co3 O4 /CoOOH nanowires (i-Ag/Co3 O4  NWs) tandem catalyst is designed to optimize the kinetic rate of intermediate reaction for NO3 RR simultaneously. The authors proved that NO3 ‾ ions are reduced to NO2 ‾ preferentially on Ag phases and then NO2 ‾ to NO on Co3 O4  phases. The CoOOH phases catalyze NO reduction to NH3  via NH2 OH intermediate. This unique catalyst efficiently converts NO3 ‾ to NH3  through a triple reaction with a high Faradaic efficiency (FE) of 94.3% and a high NH3  yield rate of 253.7 µmol h-1  cm-2  in 1 M KOH and 0.1 M KNO3  solution at -0.25 V versus RHE. The kinetic studies demonstrate that converting NH2 OH into NH3  is the rate-determining step (RDS) with an energy barrier of 0.151 eV over i-Ag/Co3 O4  NWs. Further applying i-Ag/Co3 O4  NWs as the cathode material, a novel Zn-nitrate battery exhibits a power density of 2.56 mW cm-2  and an FE of 91.4% for NH3  production.

17.
bioRxiv ; 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37745431

RESUMO

Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to lack of appropriate human models. Current human induced pluripotent stem cell (hiPSC)-derived neurons express very low levels of 4-repeat (4R)-tau isoforms that are normally expressed in adult brain. Here, we engineered new iPSC lines to express 4R-tau and 4R-tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes, including shared transcriptomic signatures, autophagic body accumulation, and impaired neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of Tau-seeding-induced Tau propagation, including retromer VPS29 and the UFMylation cascade as top modifiers. In AD brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade suppressed seeding-induced Tau propagation. This model provides a powerful platform to identify novel therapeutic strategies for 4R tauopathy.

18.
Cell ; 186(20): 4257-4259, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37774675

RESUMO

Deciphering cellular changes in Alzheimer's disease (AD) using large cohorts with defined clinical stages is essential for understanding the diverse trajectories of AD progression. In this issue of Cell, five studies harnessed the power of single-nuclei RNA sequencing (snRNA-seq) and single-nuclei ATAC sequencing (snATAC-seq) at unprecedented scale and revealed exciting insights into cell-type-specific mechanisms underlying the progression of AD pathogenesis.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Análise de Sequência de RNA , RNA Nuclear Pequeno
19.
Nat Genet ; 55(10): 1735-1744, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37735198

RESUMO

Candidate cis-regulatory elements (cCREs) in microglia demonstrate the most substantial enrichment for Alzheimer's disease (AD) heritability compared to other brain cell types. However, whether and how these genome-wide association studies (GWAS) variants contribute to AD remain elusive. Here we prioritize 308 previously unreported AD risk variants at 181 cCREs by integrating genetic information with microglia-specific 3D epigenome annotation. We further establish the link between functional variants and target genes by single-cell CRISPRi screening in microglia. In addition, we show that AD variants exhibit allelic imbalance on target gene expression. In particular, rs7922621 is the effective variant in controlling TSPAN14 expression among other nominated variants in the same cCRE and exerts multiple physiological effects including reduced cell surface ADAM10 and altered soluble TREM2 (sTREM2) shedding. Our work represents a systematic approach to prioritize and characterize AD-associated variants and provides a roadmap for advancing genetic association to experimentally validated cell-type-specific phenotypes and mechanisms.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Microglia/metabolismo , Estudo de Associação Genômica Ampla , Membrana Celular/metabolismo , Fenótipo
20.
Front Immunol ; 14: 1195421, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554321

RESUMO

Objectives: Postoperative acute kidney injury (pAKI) is a serious complication of Stanford type A aortic dissection (TAAD) surgery, which is significantly associated with the inflammatory response. This study aimed to explore the relationship between blood count-derived inflammatory markers (BCDIMs) and pAKI and to construct a predictive model for pAKI. Methods: Patients who underwent TAAD surgery were obtained from our center and the Medical Information Mart for Intensive Care (MIMIC)-IV database. The differences in preoperative BCDIMs and clinical outcomes of patients with and without pAKI were analyzed. Logistic regression was used to construct predictive models based on preoperative BCDIMs or white cell counts (WCCs). The performance of the BCDIMs and WCCs models was evaluated and compared using the receiver operating characteristic (ROC) curve, area under the ROC curve (AUC), Hosmer-Lemeshow test, calibration plot, net reclassification index (NRI), integrated discrimination improvement index (IDI), and decision curve analysis (DCA). The Kaplan-Meier curves were applied to compare the survival rate between different groups. Results: The overall incidence of pAKI in patients who underwent TAAD surgery from our center was 48.63% (124/255). The presence of pAKI was associated with longer ventilation time, higher incidence of cerebral complications and postoperative hepatic dysfunction, and higher in-hospital mortality. The results of the logistic regression indicated that the monocyte-lymphocyte ratio (MLR) was an independent risk factor for pAKI. The BCDIMs model had good discriminating ability, predictive ability, and clinical utility. In addition, the performance of the BCDIMs model was significantly better than that of the WCCs model. Analysis of data from the MIMIC-IV database validated that MLR was an independent risk factor for pAKI and had predictive value for pAKI. Finally, data from the MIMIC-IV database demonstrated that patients with a high MLR had a significantly poor 28-day survival rate when compared to patients with a low MLR. Conclusion: Our study suggested that the MLR is an independent risk factor for pAKI. A predictive model based on BCDIMs had good discriminating ability, predictive ability, and clinical utility. Moreover, the performance of the BCDIMs model was significantly better than that of the WCCs model. Finally, a high MLR was significantly associated with poor short-term survival of patients who underwent TAAD surgery.


Assuntos
Injúria Renal Aguda , Dissecção Aórtica , Humanos , Monócitos , Prognóstico , Linfócitos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Dissecção Aórtica/cirurgia
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