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2.
Dev Cell ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38996461

RESUMEN

Hematopoietic stem cell (HSC)-independent lymphopoiesis has been elucidated in murine embryos. However, our understanding regarding human embryonic counterparts remains limited. Here, we demonstrated the presence of human yolk sac-derived lymphoid-biased progenitors (YSLPs) expressing CD34, IL7R, LTB, and IRF8 at Carnegie stage 10, much earlier than the first HSC emergence. The number and lymphopoietic potential of these progenitors were both significantly higher in the yolk sac than the embryo proper at this early stage. Importantly, single-cell/bulk culture and CITE-seq have elucidated the tendency of YSLP to differentiate into innate lymphoid cells and dendritic cells. Notably, lymphoid progenitors in fetal liver before and after HSC seeding displayed distinct transcriptional features, with the former closely resembling those of YSLPs. Overall, our data identified the origin, potential, and migratory dynamics of innate lymphoid-biased multipotent progenitors in human yolk sac before HSC emergence, providing insights for understanding the stepwise establishment of innate immune system in humans.

3.
Chem Commun (Camb) ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39005163

RESUMEN

Reductive elimination is a key step in Ni-catalysed cross-couplings, which is often considered to result in new covalent bonds. Due to the weak oxidizing ability of Ni(II) species, reductive eliminations from Ni(II) centers are challenging. A thorough mechanistic understanding of this process could inspire the rational design of Ni-catalysed coupling reactions. In this article, we give an overview of recent advances in the mechanistic study of reductive elimination from Ni(II) species achieved by our group. Three possible models for reductive elimination from Ni(II) species were investigated and discussed, including direct reductive elimination, electron density-controlled reductive elimination, and oxidation-induced reductive elimination. Notably, the direct reductive elimination from Ni(II) species often requires a high activation energy in some cases. In contrast, the electron density-controlled and oxidation-induced reductive elimination pathways can significantly enhance the driving force for reductive elimination, accelerating the formation of new covalent bonds. The intricate reaction mechanisms for each of these pathways are thoroughly discussed and systematically summarized in this paper. These computational studies showcase the characteristics of three models for reductive elimination from Ni(II) species, and we hope that it will spur the development of mechanistic studies of cross-coupling reactions.

4.
Emerg Infect Dis ; 30(8): 1-13, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39043566

RESUMEN

Influenza A/H9 viruses circulate worldwide in wild and domestic avian species, continuing to evolve and posing a zoonotic risk. A substantial increase in human infections with A/H9N2 subtype avian influenza viruses (AIVs) and the emergence of novel reassortants carrying A/H9N2-origin internal genes has occurred in recent years. Different names have been used to describe the circulating and emerging A/H9 lineages. To address this issue, an international group of experts from animal and public health laboratories, endorsed by the WOAH/FAO Network of Expertise on Animal Influenza, has created a practical lineage classification and nomenclature system based on the analysis of 10,638 hemagglutinin sequences from A/H9 AIVs sampled worldwide. This system incorporates phylogenetic relationships and epidemiologic characteristics designed to trace emerging and circulating lineages and clades. To aid in lineage and clade assignment, an online tool has been created. This proposed classification enables rapid comprehension of the global spread and evolution of A/H9 AIVs.


Asunto(s)
Gripe Aviar , Gripe Humana , Filogenia , Terminología como Asunto , Animales , Humanos , Gripe Humana/epidemiología , Gripe Humana/virología , Gripe Aviar/virología , Gripe Aviar/epidemiología , Aves/virología , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/clasificación , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética
5.
Blood Sci ; 6(4): e00199, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39027902

RESUMEN

Hematopoietic stem progenitor cells (HSPCs) are derived from a specialized subset of endothelial cells named hemogenic endothelial cells (HECs) via a process of endothelial-to-hematopoietic transition during embryogenesis. Recently, with the usage of multiple single-cell technologies and advanced genetic lineage tracing techniques, namely, "TIF" approaches that combining transcriptome, immunophenotype and function/fate analyses, massive new insights have been achieved regarding the cellular and molecular evolution underlying the emergence of HSPCs from embryonic vascular beds. In this review, we focus on the most recent advances in the enrichment markers, functional characteristics, developmental paths, molecular controls, and the embryonic site-relevance of the key intermediate cell populations bridging embryonic vascular and hematopoietic systems, namely HECs and pre-hematopoietic stem cells, the immediate progenies of some HECs, in mouse and human embryos. Specifically, using expression analyses at both transcriptional and protein levels and especially efficient functional assays, we propose that the onset of Kit expression is at the HEC stage, which has previously been controversial.

6.
J Am Chem Soc ; 146(28): 19286-19294, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38956888

RESUMEN

As one of the most powerful trifluoromethylation reagents, (trifluoromethyl)trimethylsilane (TMSCF3) has been widely used for the synthesis of fluorine-containing molecules. However, to the best of our knowledge, the simultaneous incorporation of both TMS- and CF3- groups of this reagent onto the same carbon of the products has not been realized. Herein, we report an unprecedented SmI2/Sm promoted deoxygenative difunctionalization of amides with TMSCF3, in which both silyl and trifluoromethyl groups are incorporated into the final product, yielding α-silyl-α-trifluoromethyl amines with high efficiency. Notably, the silyl group could be further transformed into other functional groups, providing a new method for the synthesis of α-quaternary α-CF3-amines.

7.
Biosens Bioelectron ; 262: 116573, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39018976

RESUMEN

Drug-induced liver injury (DILI) poses a severe threat to public health. Endoplasmic reticulum (ER) stress contributes significantly to DILI pathogenesis, with peroxynitrite (ONOO-) identified as a pivotal indicator. However, the temporal and spatial fluctuations of ONOO- associated with ER stress in the pathogenesis of DILI remain unclear. Herein, a novel ER-specific near-infrared (NIR) probe (QM-ONOO) with aggregation-induced emission (AIE) features for monitoring ONOO- fluctuations in DILI was elaborately constructed. QM-ONOO exhibited excellent ER-targeting specificity, a large Stoke's shift, and a low detection limit (26.9 nM) toward ONOO-. QM-ONOO performed well in imaging both exogenous and endogenous ONOO- in HepG2 cells. Furthermore, molecular docking calculations validated the ER-targeting mechanism of QM-ONOO. Most importantly, using this probe allowed us to intuitively observe the dynamic fluctuations of ONOO- during the formation and remediation processes of DILI in the acetaminophen (APAP)-induced mouse model. Consequently, this work provides a promising tool for in-depth research of ONOO- associated pathological processes in DILI.


Asunto(s)
Acetaminofén , Enfermedad Hepática Inducida por Sustancias y Drogas , Retículo Endoplásmico , Colorantes Fluorescentes , Ácido Peroxinitroso , Ácido Peroxinitroso/metabolismo , Ácido Peroxinitroso/química , Humanos , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Colorantes Fluorescentes/química , Retículo Endoplásmico/metabolismo , Ratones , Células Hep G2 , Acetaminofén/toxicidad , Acetaminofén/efectos adversos , Técnicas Biosensibles/métodos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Simulación del Acoplamiento Molecular , Imagen Óptica/métodos
8.
Nat Commun ; 15(1): 6115, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033136

RESUMEN

Reforming sustainable 3d-metal-based visible light catalytic platforms for inert bulk chemical activation is highly desirable. Herein, we demonstrate the use of a Brønsted acid to unlock robust and practical iron ligand-to-metal charge transfer (LMCT) photocatalysis for the activation of multifarious inert haloalkylcarboxylates (CnXmCOO-, X = F or Cl) to produce CnXm radicals. This process enables the fluoro-polyhaloalkylation of non-activated alkenes by combining easily available Selectfluor as a fluorine source. Valuable alkyl fluorides including potential drug molecules can be easily obtained through this protocol. Mechanistic studies indicate that the real light-harvesting species may derive from the in situ-assembly of Fe3+, CnXmCOO-, H+, and acetonitrile solvent, in which the Brønsted acid indeed increases the efficiency of LMCT between the iron center and CnXmCOO- via hydrogen-bond interactions. We anticipate that this Brønsted acid-unlocked iron LMCT platform would be an intriguing sustainable option to execute the activation of inert compounds.

9.
Nat Commun ; 15(1): 6183, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39039050

RESUMEN

The de novo construction of enantioenriched 3-hydroxyindolenines and 3-oxindoles from easily available starting materials has been highly desired. Herein, an enantioselectively intermolecular direct [3 + 2] annulation of aryl amine with 2,3-diketoesters to construct 3-hydroxyindolenines with a chiral tertiary alcohol has been disclosed. The results of control experiments and DFT calculation revealed that π - π interaction plays a pivotal role in the enantioselectivity-determining process of [3 + 2] annulation. The following unusual concerted [1,2]-ester migration provides a family of chiral 3-oxindoles in good to excellent yields with excellent enantioselectivity.

10.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3684-3692, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39041141

RESUMEN

Coronary heart disease is a common cardiovascular disease, attacking about 11.4 million patients in China. With increasing prevalence and mortality year by year, coronary heart disease has become a major factor threatening human health and public health. Although primary and secondary prevention, intervention, coronary artery bypass grafting and other interventions have reduced the death rate, there are drug(aspirin) resistance, secondary nitroglycerin failure, post-intervention fatigue, chest tightness, and an-xiety, and complication with a high risk of bleeding, which have become the key clinical and scientific issues needed to be resolved. Coronary heart disease belongs to the category of chest impediment and heart pain in traditional Chinese medicine(TCM). The TCM etiology of this disease includes external contraction of cold, emotional disorders, constitutional insufficiency, physical weakness, and labor injury, which are closely related to sympathetic nerve activity, state of cardiac and psychological diseases, family history, and cardiovascular metabolic disorders in modern medicine. The TCM causes of coronary heart disease include Qi depression, phlegm turbidity, blood stasis, fire-heat, cold congealing, and healthy Qi deficiency, which are associated with emotional factors such as anxiety and depression, abnormal lipid metabolism, abnormalities in blood circulation and coagulation, inflammatory responses, hyperactive immune responses, and heart failure, chronic wasting disease, or aging, respectively. Accordingly, the patients with Qi depression should be treated with Chaihu Longgu Muli Decoction, and those with phlegm turbidity should be treated with Wendan Decoction and Gualou Xiebai Banxia Decoction. Xuefu Zhuyu Decoction and Guizhi Fuling Pills are recommended for blood stasis, Xiaoxianxiong Decoction and Sanhuang Xiexin Decoction for fire-heat, Zhishi Xiebai Guizhi Decoction for cold congealing, and Renshen Decoction for healthy Qi deficiency. Due to the changes in the spectrum of diseases from ancient to modern times as well as the differences in physical constitution, the key cause of coronary heart disease has evolved from the chest Yang deficiency and cold congealing to Qi depression, phlegm turbidity, phlegm combined with stasis, and fire-heat, showing a shift from cold to heat and from deficiency to excess. The combination of classic formulas presents a pattern. That is, the core formula-syndrome correspondence of a disease often fixedly appears with other formula-syndrome correspondence, which may be related to the development of the pathophysiological mechanism of the disease. In the clinical application of modern pharmacological results, the research team has formulated the clinical principle of pathogenesis corresponding to pathological changes and medicinal nature corresponding pharmacological effects. The modern pharmacological research on classic formulas is conducive to targeted treatment. Moreover, classic formulas help to ameliorate aspirin resistance, clopidogrel resistance, post-intervention anxiety, and high risk of bleeding and address the lack of effective blockade of critical lesions in the coronary artery and the progression of post-infarction heart failure. The innovative understanding of the etiology and pathogenesis of co-ronary heart disease helps to improve the clinical efficacy of TCM and the clinical system for treating coronary heart disease with classic formulas.


Asunto(s)
Enfermedad Coronaria , Medicamentos Herbarios Chinos , Medicina Tradicional China , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Enfermedad Coronaria/tratamiento farmacológico
11.
Nat Commun ; 15(1): 5479, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942777

RESUMEN

1,2-Difunctionalization of alkynes offers a straightforward approach to access polysubstituted alkenes. However, simultaneous multi-component cascade transformations including difunctionalization of two alkynes with both syn- and anti-selectivity in one catalyst system is undeveloped and proves to be a significant challenge. Herein, we report a Nickel-catalyzed four-component reaction to access polysubstituted 1,3-dienes using two terminal alkynes, aryl boroxines, and perfluoroalkyl iodides, wherein the reaction forms three new C-C bonds in a single vessel and serve as a modular strategy to access polysubstituted 1,3-dienes with excellent chemoselectivity, good regioselectivity and exclusive stereoselectivity. Control experiments reveal the plausible reaction mechanism and DFT calculations explain the cause for the formation of this unusual four-component reaction. Furthermore, we successfully incorporate two biologically active units into 1,2,3,4-tetrasubstituted 1,3-dienes, which greatly increases the diversity of molecular scaffolds and brings more potential values to medicinal chemistry, the synthetic utility of our protocol is further demonstrated by the late-stage transformations.

12.
Biomed Pharmacother ; 176: 116864, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38865847

RESUMEN

BACKGROUND: DNA repair allows the survival of cancer cells. Therefore, the development of DNA repair inhibitors is a critical need for sensitizing cancers to chemoradiation. Sae2CtIP has specific functions in initiating DNA end resection, as well as coordinating cell cycle checkpoints, and it also greatly interacts with the DDR at different levels. RESULTS: In this study, we demonstrated that corylin, a potential sensitizer, causes deficiencies in DNA repair and DNA damage checkpoints in yeast cells. More specifically, corylin increases DNA damage sensitivity through the Sae2-dependent pathway and impairs the activation of Mec1-Ddc2, Rad53-p and γ-H2A. In breast cancer cells, corylin increases apoptosis and reduces proliferation following Dox treatment by inhibiting CtIP. Xenograft assays showed that treatment with corylin combined with Dox significantly reduced tumor growth in vivo. CONCLUSIONS: Our findings herein delineate the mechanisms of action of corylin in regulating DNA repair and indicate that corylin has potential long-term clinical utility as a DDR inhibitor.


Asunto(s)
Daño del ADN , Reparación del ADN , Recombinación Homóloga , Humanos , Animales , Reparación del ADN/efectos de los fármacos , Recombinación Homóloga/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Femenino , Ratones Desnudos , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efectos de los fármacos , Doxorrubicina/farmacología , Ratones , Ratones Endogámicos BALB C , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
13.
Adv Sci (Weinh) ; : e2309021, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38923244

RESUMEN

Targeting receptor-interacting protein kinase 1 (RIPK1) has emerged as a promising therapeutic stratagem for neurodegenerative disorders, particularly Alzheimer's disease (AD). A positron emission tomography (PET) probe enabling brain RIPK1 imaging can provide a powerful tool to unveil the neuropathology associated with RIPK1. Herein, the development of a new PET radioligand, [11C]CNY-10 is reported, which may enable brain RIPK1 imaging. [11C]CNY-10 is radiosynthesized with a high radiochemical yield (41.8%) and molar activity (305 GBq/µmol). [11C]CNY-10 is characterized by PET imaging in rodents and a non-human primate, demonstrating good brain penetration, binding specificity, and a suitable clearance kinetic profile. It is performed autoradiography of [11C]CNY-10 in human AD and healthy control postmortem brain tissues, which shows strong radiosignal in AD brains higher than healthy controls. Subsequently, it is conducted further characterization of RIPK1 in AD using [11C]CNY-10-based PET studies in combination with immunohistochemistry leveraging the 5xFAD mouse model. It is found that AD mice revealed RIPK1 brain signal significantly higher than WT control mice and that RIPK1 is closely related to amyloid plaques in the brain. The studies enable further translational studies of [11C]CNY-10 for AD and potentially other RIPK1-related human studies.

15.
Infect Drug Resist ; 17: 2513-2529, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919832

RESUMEN

Background: Minocycline, a derivative of tetracycline, has anti-Helicobacter pylori (H. pylori) properties and can be used to treat H. pylori infection. However, only a few randomized controlled trials (RCTs) have investigated the efficacy of minocycline-containing quadruple therapy (MCQT) in treating H. pylori infection. This study aimed to determine the efficacy and safety of MCQT and investigate the factors influencing both aspects. Methods: This was a retrospective cohort study. Patients diagnosed with H. pylori infection between January 1, 2022, and July 31, 2023 at. The primary outcome was the eradication rate of H. pylori, and the secondary outcome was the number and type of adverse events. Results: A total of 828 patients were included in this study. The overall H. pylori eradication rate among the included patients at 95% confidence interval (CI) (Range 0.864 to 0.907) was 88.53%. The H. pylori eradication rate for patients who received MCQT regimen as the primary therapy was 92.28% (95% CI: 0.901-0.945), significantly higher than that of patients who received MCQT as rescue therapy (80.81%; 95% CI: 0.761-0.855, P=0.003). Adverse events, including dizziness, abdominal distension, diarrhea, nausea, abdominal discomfort, constipation, headache, rash, sleep disorder, palpitation, backache, and anorexia, occurred in 185 (22.34%) patients, with dizziness being the most common (75/828, 9.06%). Compliance with MCQT therapy was an independent factor influencing H. pylori eradication in patients receiving MCQT as a primary therapy. Compliance and presence or absence of H. pylori infection symptoms at the time of screening were independent factors influencing H. Pylori eradication in patients receiving MCQT as rescue therapy. Factors that influenced the occurrence of adverse events included reasons for H. pylori infection screening, residence, treatment compliance, and the use of acid-suppressant regimens. Conclusion: MCQT regimens were effective in H. pylori infection eradication, and the treatment resulted only in fewer adverse events when used as primary or rescue therapies for H. pylori infection treatment. Future prospective studies with larger sample sizes and more comprehensive data are needed to validate our findings.

16.
J Acoust Soc Am ; 155(6): 3600-3603, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38829157

RESUMEN

The drive-stack design principle for the Tonpilz transducer aiming to transmit the acoustic signal in an ultra-wideband has been proposed [(2023). J. Acoust. Soc. Am. 154, 3709-3725], in which the design method is obtained and validated through simulation. This letter presents the experimental investigation of a fabricated transducer prototype and gives the measurement results of electroacoustic performance, including the electrical admittance, transmitting voltage response, directivity beam pattern, electroacoustic efficiency, and source level. The results indicate that the transducer can operate in the frequency band from 20 to 80 kHz without deep response notches within the band.

18.
PLoS One ; 19(5): e0303832, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820283

RESUMEN

BACKGROUND: Osteoprotegerin (OPG) is supposed to participate in the development of atherosclerosis and cardio-cerebrovascular disease. However, the results of research on relationship between OPG and ischemic stroke (IS) are controversial. Therefore, we carried out the first systematic review and meta-analysis to evaluate prognostic effect of osteoprotegerin in patients with IS. METHODS: We comprehensively searched databases of PubMed, Embase, and the Cochrane Library through 21 August 2023 to identify observational studies that evaluated effect of OPG on poor functional outcome (modified Rankin Scale [mRS] Score of 3-6) and mortality in patients with IS. Adjusted odds ratios (aOR) with a 95% confidence interval (CI) of each included study were used as much as possible to assess the pooled effect. RESULTS: Five studies that enrolled 4,506 patients in total fulfilled our inclusion criteria. Three studies were included in the pooled analysis for each endpoint since one of the included studies had provided data on poor functional outcome as well as mortality. OPG was neither associated with poor functional outcome (aOR 1.29, 95% CI 0.90-1.85) nor with mortality (aOR 1.57, 95% CI 0.90-2.74) in patients with IS. CONCLUSIONS: There is insufficient evidence to demonstrate the correlation between OPG and mortality or poor functional outcome in IS patients. OPG cannot be applied to predict worse neurological function in IS patients based on the current evidence.


Asunto(s)
Accidente Cerebrovascular Isquémico , Osteoprotegerina , Humanos , Accidente Cerebrovascular Isquémico/mortalidad , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Pronóstico
19.
Nature ; 631(8021): 556-562, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38806060

RESUMEN

Asymmetric catalysis enables the synthesis of optically active compounds, often requiring the differentiation between two substituents on prochiral substrates1. Despite decades of development of mainly noble metal catalysts, achieving differentiation between substituents with similar steric and electronic properties remains a notable challenge2,3. Here we introduce a class of Earth-abundant manganese catalysts for the asymmetric hydrogenation of dialkyl ketimines to give a range of chiral amine products. These catalysts distinguish between pairs of minimally differentiated alkyl groups bound to the ketimine, such as methyl and ethyl, and even subtler distinctions, such as ethyl and n-propyl. The degree of enantioselectivity can be adjusted by modifying the components of the chiral manganese catalyst. This reaction demonstrates a wide substrate scope and achieves a turnover number of up to 107,800. Our mechanistic studies indicate that exceptional stereoselectivity arises from the modular assembly of confined chiral catalysts and cooperative non-covalent interactions between the catalyst and the substrate.


Asunto(s)
Iminas , Manganeso , Nitrilos , Hidrogenación , Catálisis , Iminas/química , Estereoisomerismo , Nitrilos/química , Manganeso/química , Aminas/química , Aminas/síntesis química
20.
Chem Commun (Camb) ; 60(44): 5707-5710, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38738645

RESUMEN

A tandem palladium-catalyzed Sonogashira coupling, propargyl-allenyl isomerization, and [2+2] cycloaddition sequence between electron-deficient haloarenes and 1,8-diynylic ethers is developed. The reaction shows good functional tolerance and proceeds under mild conditions to provide a new profile of benzooxepane-fused cyclobutene derivatives in moderate to high yields with high selectivity. The reaction mechanism is validated both by experimental studies and DFT calculations.

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