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1.
Nature ; 595(7865): 107-113, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33915569

RESUMO

COVID-19, which is caused by SARS-CoV-2, can result in acute respiratory distress syndrome and multiple organ failure1-4, but little is known about its pathophysiology. Here we generated single-cell atlases of 24 lung, 16 kidney, 16 liver and 19 heart autopsy tissue samples and spatial atlases of 14 lung samples from donors who died of COVID-19. Integrated computational analysis uncovered substantial remodelling in the lung epithelial, immune and stromal compartments, with evidence of multiple paths of failed tissue regeneration, including defective alveolar type 2 differentiation and expansion of fibroblasts and putative TP63+ intrapulmonary basal-like progenitor cells. Viral RNAs were enriched in mononuclear phagocytic and endothelial lung cells, which induced specific host programs. Spatial analysis in lung distinguished inflammatory host responses in lung regions with and without viral RNA. Analysis of the other tissue atlases showed transcriptional alterations in multiple cell types in heart tissue from donors with COVID-19, and mapped cell types and genes implicated with disease severity based on COVID-19 genome-wide association studies. Our foundational dataset elucidates the biological effect of severe SARS-CoV-2 infection across the body, a key step towards new treatments.


Assuntos
COVID-19/patologia , COVID-19/virologia , Rim/patologia , Fígado/patologia , Pulmão/patologia , Miocárdio/patologia , SARS-CoV-2/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Atlas como Assunto , Autopsia , Bancos de Espécimes Biológicos , COVID-19/genética , COVID-19/imunologia , Células Endoteliais , Células Epiteliais/patologia , Células Epiteliais/virologia , Feminino , Fibroblastos , Estudo de Associação Genômica Ampla , Coração/virologia , Humanos , Inflamação/patologia , Inflamação/virologia , Rim/virologia , Fígado/virologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Fagócitos , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/virologia , RNA Viral/análise , Regeneração , SARS-CoV-2/imunologia , Análise de Célula Única , Carga Viral
2.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38372291

RESUMO

The ecological validity of bilingual code-switching has garnered increasing attention in recent years. Contrary to traditional studies that have focused on forced language switching, emerging theories posit that voluntary switching may not incur such a cost. To test these claims and understand differences between forced and voluntary switching, the present study conducted a systematic comparison through both behavioral and neural perspectives. Utilizing fMRI alongside picture-naming tasks, our findings diverge from prior work. Voluntary language switching not only demonstrated switching costs at the behavioral level but also significantly activated brain regions associated with inhibitory control. Direct comparisons of voluntary and forced language switching revealed no significant behavioral differences in switching costs, and both shared several common brain regions that were activated. On the other hand, a nuanced difference between the two types of language switching was revealed by whole-brain analysis: voluntary switching engaged fewer language control regions than forced switching. These findings offer a comprehensive view of the neural and behavioral dynamics involved in bilingual language switching, challenging prior claims that voluntary switching imposes no behavioral or neural costs, and thus providing behavioral and neuroimaging evidence for the involvement of inhibitory control in voluntary language switching.


Assuntos
Imageamento por Ressonância Magnética , Multilinguismo , Humanos , Idioma , Cognição , China
3.
J Am Chem Soc ; 146(9): 6283-6293, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381856

RESUMO

We herein introduce biarylhemiboronic esters as a new type of bridged biaryl reagent for asymmetric synthesis of axially chiral biaryl structures, and the palladium-catalyzed asymmetric Suzuki-Miyaura cross-coupling of biarylhemiboronic esters is developed. This dynamic kinetic atroposelective coupling reaction exhibits high enantioselectivity, good functional group tolerance, and a broad substrate scope. The synthetic application of the current method was demonstrated by transformations of the product and a programmed synthesis of chiral polyarene. Preliminary mechanistic studies suggested that the reaction proceeded via an enantio-determining dynamic kinetic atroposelective transmetalation step.

4.
J Synchrotron Radiat ; 31(Pt 5): 1249-1256, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007823

RESUMO

StreamSAXS is a Python-based small- and wide-angle X-ray scattering (SAXS/WAXS) data analysis workflow platform with graphical user interface (GUI). It aims to provide an interactive and user-friendly tool for analysis of both batch data files and real-time data streams. Users can easily create customizable workflows through the GUI to meet their specific needs. One characteristic of StreamSAXS is its plug-in framework, which enables developers to extend the built-in workflow tasks. Another feature is the support for both already acquired and real-time data sources, allowing StreamSAXS to function as an offline analysis platform or be integrated into large-scale acquisition systems for end-to-end data management. This paper presents the core design of StreamSAXS and provides user cases demonstrating its utilization for SAXS/WAXS data analysis in offline and online scenarios.

5.
J Transl Med ; 22(1): 174, 2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369502

RESUMO

BACKGROUND: Overexpression of T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3) is related to the exhaustion of CD8+ tumor-infiltrating lymphocytes (TILs) in diffuse large B-cell lymphoma (DLBCL). However, the mechanism of TIM3-mediated CD8+TILs exhaustion in DLBCL remains poorly understood. Therefore, we aimed to clarify the potential pathway involved in TIM3-mediated CD8+TILs exhaustion and its significance in DLBCL. METHODS: The expression of TIM3 and its correlation with CD8+TILs exhaustion, the key ligand of TIM3, and the potential pathway of TIM3-mediated CD8+TILs exhaustion in DLBCL were analyzed using single-cell RNA sequencing and validated by RNA sequencing. The biological significance of TIM3-related pathway in DLBCL was investigated based on RNA sequencing, immunohistochemistry, and reverse transcription-quantitative polymerase chain reaction data. Finally, the possible regulatory mechanism of TIM3-related pathway in DLBCL was explored using single-cell RNA sequencing and RNA sequencing. RESULTS: Our results demonstrated that CD8+TILs, especially the terminally exhausted state, were the major clusters that expressed TIM3 in DLBCL. Galectin-9, mainly expressed in M2 macrophages, is the key ligand of TIM3 and can induce the exhaustion of CD8+TILs through TIM3/Galectin-9 pathway. Meanwhile, high TIM3/Galectin-9 enrichment is related to immunosuppressive tumor microenvironment, severe clinical manifestations, inferior prognosis, and poor response to CHOP-based chemotherapy, and can predict the clinical efficacy of immune checkpoint blockade therapy in DLBCL. Furthermore, the TIM3/Galectin-9 enrichment in DLBCL may be regulated by the IFN-γ signaling pathway. CONCLUSIONS: Our study highlights that TIM3/Galectin-9 pathway plays a crucial role in CD8+TILs exhaustion and the immune escape of DLBCL, which facilitates further functional studies and could provide a theoretical basis for the development of novel immunotherapy in DLBCL.


Assuntos
Linfócitos T CD8-Positivos , Galectinas , Receptor Celular 2 do Vírus da Hepatite A , Linfoma Difuso de Grandes Células B , Humanos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Ligantes , Linfócitos do Interstício Tumoral , Linfoma Difuso de Grandes Células B/patologia , Microambiente Tumoral , Galectinas/metabolismo
6.
Nutr Cancer ; 76(10): 885-901, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39066475

RESUMO

Epimedium is a Chinese herb known as "yin and yang fire," first mentioned in the Compendium of Materia Medica. Many of the proprietary Chinese medicines used in clinical practice contain Epimedium as an ingredient, and its main active constituents include icariin, icaritin, and icariside II, among others. In addition to its traditional use in treating fatigue and sexual problems, modern research has confirmed that the main bioactive compounds in Epimedium have pharmacological effects such as antidepressant, antibacterial, antiviral, antioxidant, and anti-inflammatory properties, as well as inhibiting bone destruction, promoting bone growth, improving immune regulation and protecting the cardio-cerebral vascular system. With the continuous development of extraction and purification techniques, the development and use of bioactive compounds in Epimedium have significantly progressed, and the anticancer effect has received widespread attention. Since natural herbs have few side effects on the human body and do not easily develop drug resistance, they have long been the direction of research in cancer treatment. This review summarizes the latest research on the anticancer effects of Epimedium and its extracts, describes the bioactive compounds, pharmacological efficacy, and antitumor mechanism of Epimedium, and gives a new view on the administration and development of Epimedium.


Assuntos
Epimedium , Neoplasias , Epimedium/química , Humanos , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Flavonoides/farmacologia
7.
J Org Chem ; 89(16): 11446-11454, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39113180

RESUMO

An enzyme catalyzed strategy for the synthesis of a chiral hydrazine from 3-cyclopentyl-3-oxopropanenitrile 5 and hydrazine hydrate 2 is presented. An imine reductase (IRED) from Streptosporangium roseum was identified to catalyze the reaction between 3-cyclopentyl-3-oxopropanenitrile 5 and hydrazine hydrate 2 to produce trace amounts of (R)-3-cyclopentyl-3-hydrazineylpropanenitrile 4. We employed a 2-fold approach to optimize the catalytic performance of this enzyme. First, a transition state analogue (TSA) model was constructed to illuminate the enzyme-substrate interactions. Subsequently, the Enzyme_design and Funclib methods were utilized to predict mutants for experimental evaluation. Through three rounds of site-directed mutagenesis, site saturation mutagenesis, and combinatorial mutagenesis, we obtained mutant M6 with a yield of 98% and an enantiomeric excess (ee) of 99%. This study presents an effective method for constructing a hydrazine derivative via IRED-catalyzed reductive amination of ketone and hydrazine. Furthermore, it provides a general approach for constructing suitable enzymes, starting from nonreactive enzymes and gradually enhancing their catalytic activity through active site modifications.


Assuntos
Biocatálise , Nitrilas , Oxirredutases , Pirazóis , Pirimidinas , Nitrilas/química , Nitrilas/metabolismo , Pirimidinas/química , Pirimidinas/biossíntese , Pirimidinas/metabolismo , Oxirredutases/metabolismo , Oxirredutases/genética , Pirazóis/química , Pirazóis/metabolismo , Iminas/química , Iminas/metabolismo , Estrutura Molecular , Hidrazinas/química , Engenharia de Proteínas
8.
Molecules ; 29(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675712

RESUMO

Schisandra chinensis, as a traditional Chinese herbal medicine, has clear pharmacological effects such as treating asthma, protecting nerves and blood vessels, and having anti-inflammatory properties. Although the Schisandra chinensis fruit contain multiple active components, the lignans have been widely studied as the primary pharmacologically active compound. The volatile chemical components of Schisandra chinensis include a large amount of terpenes, which have been proven to have broad pharmacological activities. However, when to harvest to ensure the highest accumulation of pharmacologically active components in Schisandra chinensis fruits is a critical issue. The Schisandra chinensis fruit trees in the resource nursery were all planted in 2019 and began bearing fruit in 2021. Their nutritional status and tree vigor remain consistently good. The content of lignans and organic acids in the fruits of Schisandra chinensis over seven different harvest periods was tested, and the results of high-performance liquid chromatography (HPLC) indicated that the lignan content was higher, at 35 mg/g, in late July, and the organic acid content was higher, at 72.34 mg/g, in early September. If lignans and organic acids are to be selected as raw materials for pharmacological development, the harvest can be carried out at this stage. Using HS-GC-IMS technology, a total of 67 volatile flavor substances were detected, and the fingerprint of the volatile flavor substances in the different picking periods was established. It was shown by the results that the content of volatile flavor substances was the highest in early August, and 16 flavor substances were selected by odor activity value (OAV). The variable importance in projection (VIP) values of 16 substances were further screened, and terpinolene was identified as the key volatile flavor substance that caused the aroma characteristics of Schisandra chinensis fruit at different harvesting periods. If the aroma component content of Schisandra chinensis fruit is planned to be used as raw material for development and utilization, then early August, when the aroma component content is higher, should be chosen as the time for harvest. This study provides a theoretical basis for the suitable harvesting time of Schisandra chinensis for different uses, and promotes the high-quality development of the Schisandra chinensis industry.


Assuntos
Frutas , Schisandra , Schisandra/química , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Lignanas/análise , Lignanas/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas/métodos
9.
Angew Chem Int Ed Engl ; 63(5): e202316087, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38093609

RESUMO

Solid-state lithium-sulfur batteries have shown prospects as safe, high-energy electrochemical storage technology for powering regional electrified transportation. Owing to limited ion mobility in crystalline polymer electrolytes, the battery is incapable of operating at subzero temperature. Addition of liquid plasticizer into the polymer electrolyte improves the Li-ion conductivity yet sacrifices the mechanical strength and interfacial stability with both electrodes. In this work, we showed that by introducing a spherical hyperbranched solid polymer plasticizer into a Li+ -conductive linear polymer matrix, an integrated dynamic cross-linked polymer network was built to maintain fully amorphous in a wide temperature range down to subzero. A quasi-solid polymer electrolyte with a solid mass content >90 % was prepared from the cross-linked polymer network, and demonstrated fast Li+ conduction at a low temperature, high mechanical strength, and stable interfacial chemistry. As a result, solid-state lithium-sulfur batteries employing the new electrolyte delivered high reversible capacity and long cycle life at 25 °C, 0 °C and -10 °C to serve energy storage at complex environmental conditions.

10.
Pak J Pharm Sci ; 37(2(Special)): 463-473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38822551

RESUMO

Solanum lyratum Thunb., a traditional Chinese herbal medicine, has a promising background. However, the anti-inflammatory effects of its component steroid alkaloid have not been explored. In this study, animal and cell experiments were performed to investigate the anti-inflammatory effects and mechanism of action of Solanum lyratum Thunb steroid alkaloid (SLTSA), in order to provide evidence for its potential utilization. SLTSA effectively inhibited ear swelling and acute abdominal inflammation of mice. We observed concentration-dependent inhibition of pro-inflammatory cytokines by SLTSA, as confirmed by the ELISA and RT-qPCR results. Flow cytometry, immunofluorescence and RT-qPCR analyses revealed that SLTSA suppressed TLR4 expression. Western blot results indicated that SLTSA inhibited the activation of the TLR4/MyD88/NF-κB signaling pathway. Our study demonstrated that SLTSA possesses anti-inflammatory properties.


Assuntos
Alcaloides , Anti-Inflamatórios , Transdução de Sinais , Solanum , Animais , Solanum/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Camundongos , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Citocinas/metabolismo , Células RAW 264.7 , Fator 88 de Diferenciação Mieloide/metabolismo , Masculino
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