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1.
Cell ; 187(4): 897-913.e18, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280374

RESUMO

Canonically, the complement system is known for its rapid response to remove microbes in the bloodstream. However, relatively little is known about a functioning complement system on intestinal mucosal surfaces. Herein, we report the local synthesis of complement component 3 (C3) in the gut, primarily by stromal cells. C3 is expressed upon commensal colonization and is regulated by the composition of the microbiota in healthy humans and mice, leading to an individual host's specific luminal C3 levels. The absence of membrane attack complex (MAC) components in the gut ensures that C3 deposition does not result in the lysis of commensals. Pathogen infection triggers the immune system to recruit neutrophils to the infection site for pathogen clearance. Basal C3 levels directly correlate with protection against enteric infection. Our study reveals the gut complement system as an innate immune mechanism acting as a vigilant sentinel that combats pathogens and spares commensals.


Assuntos
Complemento C3 , Mucosa Intestinal , Microbiota , Animais , Humanos , Camundongos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Neutrófilos , Complemento C3/metabolismo , Células Estromais/metabolismo
2.
Nature ; 619(7971): 837-843, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380774

RESUMO

The human gut microbiome constantly converts natural products derived from the host and diet into numerous bioactive metabolites1-3. Dietary fats are essential micronutrients that undergo lipolysis to release free fatty acids (FAs) for absorption in the small intestine4. Gut commensal bacteria modify some unsaturated FAs-for example, linoleic acid (LA)-into various intestinal FA isomers that regulate host metabolism and have anticarcinogenic properties5. However, little is known about how this diet-microorganism FA isomerization network affects the mucosal immune system of the host. Here we report that both dietary factors and microbial factors influence the level of gut LA isomers (conjugated LAs (CLAs)) and that CLAs in turn modulate a distinct population of CD4+ intraepithelial lymphocytes (IELs) that express CD8αα in the small intestine. Genetic abolition of FA isomerization pathways in individual gut symbionts significantly decreases the number of CD4+CD8αα+ IELs in gnotobiotic mice. Restoration of CLAs increases CD4+CD8αα+ IEL levels in the presence of the transcription factor hepatocyte nuclear factor 4γ (HNF4γ). Mechanistically, HNF4γ facilitates CD4+CD8αα+ IEL development by modulating interleukin-18 signalling. In mice, specific deletion of HNF4γ in T cells leads to early mortality from infection by intestinal pathogens. Our data reveal a new role for bacterial FA metabolic pathways in the control of host intraepithelial immunological homeostasis by modulating the relative number of CD4+ T cells that were CD4+CD8αα+.


Assuntos
Ácidos Graxos , Microbioma Gastrointestinal , Linfócitos Intraepiteliais , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Isomerismo , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Lipólise , Ácido Linoleico/metabolismo , Imunidade nas Mucosas
3.
Nature ; 617(7960): 377-385, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37138075

RESUMO

The gut microbiota is a crucial regulator of anti-tumour immunity during immune checkpoint inhibitor therapy. Several bacteria that promote an anti-tumour response to immune checkpoint inhibitors have been identified in mice1-6. Moreover, transplantation of faecal specimens from responders can improve the efficacy of anti-PD-1 therapy in patients with melanoma7,8. However, the increased efficacy from faecal transplants is variable and how gut bacteria promote anti-tumour immunity remains unclear. Here we show that the gut microbiome downregulates PD-L2 expression and its binding partner repulsive guidance molecule b (RGMb) to promote anti-tumour immunity and identify bacterial species that mediate this effect. PD-L1 and PD-L2 share PD-1 as a binding partner, but PD-L2 can also bind RGMb. We demonstrate that blockade of PD-L2-RGMb interactions can overcome microbiome-dependent resistance to PD-1 pathway inhibitors. Antibody-mediated blockade of the PD-L2-RGMb pathway or conditional deletion of RGMb in T cells combined with an anti-PD-1 or anti-PD-L1 antibody promotes anti-tumour responses in multiple mouse tumour models that do not respond to anti-PD-1 or anti-PD-L1 alone (germ-free mice, antibiotic-treated mice and even mice colonized with stool samples from a patient who did not respond to treatment). These studies identify downregulation of the PD-L2-RGMb pathway as a specific mechanism by which the gut microbiota can promote responses to PD-1 checkpoint blockade. The results also define a potentially effective immunological strategy for treating patients who do not respond to PD-1 cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Imunoterapia , Melanoma , Microbiota , Animais , Humanos , Camundongos , Moléculas de Adesão Celular Neuronais , Modelos Animais de Doenças , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transplante de Microbiota Fecal , Vida Livre de Germes , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/imunologia , Melanoma/microbiologia , Melanoma/terapia , Ligação Proteica/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
4.
Nature ; 577(7791): 543-548, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915378

RESUMO

Although maternal antibodies protect newborn babies from infection1,2, little is known about how protective antibodies are induced without prior pathogen exposure. Here we show that neonatal mice that lack the capacity to produce IgG are protected from infection with the enteric pathogen enterotoxigenic Escherichia coli by maternal natural IgG antibodies against the maternal microbiota when antibodies are delivered either across the placenta or through breast milk. By challenging pups that were fostered by either maternal antibody-sufficient or antibody-deficient dams, we found that IgG derived from breast milk was crucial for protection against mucosal disease induced by enterotoxigenic E. coli. IgG also provides protection against systemic infection by E. coli. Pups used the neonatal Fc receptor to transfer IgG from milk into serum. The maternal commensal microbiota can induce antibodies that recognize antigens expressed by enterotoxigenic E. coli and other Enterobacteriaceae species. Induction of maternal antibodies against a commensal Pantoea species confers protection against enterotoxigenic E. coli in pups. This role of the microbiota in eliciting protective antibodies to a specific neonatal pathogen represents an important host defence mechanism against infection in neonates.


Assuntos
Anticorpos/imunologia , Escherichia coli Enterotoxigênica/imunologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/prevenção & controle , Imunidade Materno-Adquirida/imunologia , Recém-Nascido/imunologia , Microbiota/imunologia , Leite Humano/imunologia , Animais , Anticorpos/sangue , Anticorpos/metabolismo , Aleitamento Materno , Reações Cruzadas/imunologia , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Masculino , Camundongos , Mães , Pantoea/imunologia , Receptores Fc/imunologia , Receptores Fc/metabolismo , Simbiose/imunologia
5.
Nature ; 577(7790): 410-415, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31875848

RESUMO

The metabolic pathways encoded by the human gut microbiome constantly interact with host gene products through numerous bioactive molecules1. Primary bile acids (BAs) are synthesized within hepatocytes and released into the duodenum to facilitate absorption of lipids or fat-soluble vitamins2. Some BAs (approximately 5%) escape into the colon, where gut commensal bacteria convert them into various intestinal BAs2 that are important hormones that regulate host cholesterol metabolism and energy balance via several nuclear receptors and/or G-protein-coupled receptors3,4. These receptors have pivotal roles in shaping host innate immune responses1,5. However, the effect of this host-microorganism biliary network on the adaptive immune system remains poorly characterized. Here we report that both dietary and microbial factors influence the composition of the gut BA pool and modulate an important population of colonic FOXP3+ regulatory T (Treg) cells expressing the transcription factor RORγ. Genetic abolition of BA metabolic pathways in individual gut symbionts significantly decreases this Treg cell population. Restoration of the intestinal BA pool increases colonic RORγ+ Treg cell counts and ameliorates host susceptibility to inflammatory colitis via BA nuclear receptors. Thus, a pan-genomic biliary network interaction between hosts and their bacterial symbionts can control host immunological homeostasis via the resulting metabolites.


Assuntos
Ácidos e Sais Biliares/metabolismo , Microbioma Gastrointestinal , Homeostase , Intestinos/imunologia , Intestinos/microbiologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Reguladores/imunologia , Animais , Ácidos e Sais Biliares/química , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética
6.
Proc Natl Acad Sci U S A ; 120(37): e2309714120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669377

RESUMO

Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by Tars2), disruption of which accumulated Ser-tRNAThr and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo. Such infidelity impaired mitochondrial translation and oxidative phosphorylation, causing oxidative stress and cell cycle arrest in the G0/G1 phase. Notably, reactive oxygen species (ROS) scavenging by N-acetylcysteine attenuated this abnormal cell proliferation. A mouse model of heart-specific defective mtThrRS editing was established. Increased ROS levels, blocked cardiomyocyte proliferation, contractile dysfunction, dilated cardiomyopathy, and cardiac fibrosis were observed. Our results elucidate that mitochondria critically require a high level of translational accuracy at Thr codons and highlight the cellular dysfunctions and imbalance in tissue homeostasis caused by mitochondrial mistranslation.


Assuntos
Aminoacil-tRNA Sintetases , Cardiomiopatias , Cardiopatias , Animais , Camundongos , Espécies Reativas de Oxigênio , Pontos de Checagem do Ciclo Celular , Estresse Oxidativo , Mamíferos
7.
Proc Natl Acad Sci U S A ; 120(42): e2306710120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37824525

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic and the measures taken by authorities to control its spread have altered human behavior and mobility patterns in an unprecedented way. However, it remains unclear whether the population response to a COVID-19 outbreak varies within a city or among demographic groups. Here, we utilized passively recorded cellular signaling data at a spatial resolution of 1 km × 1 km for over 5 million users and epidemiological surveillance data collected during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2 outbreak from February to June 2022 in Shanghai, China, to investigate the heterogeneous response of different segments of the population at the within-city level and examine its relationship with the actual risk of infection. Changes in behavior were spatially heterogenous within the city and population groups and associated with both the infection incidence and adopted interventions. We also found that males and individuals aged 30 to 59 y old traveled more frequently, traveled longer distances, and their communities were more connected; the same groups were also associated with the highest SARS-CoV-2 incidence. Our results highlight the heterogeneous behavioral change of the Shanghai population to the SARS-CoV-2 Omicron BA.2 outbreak and the effect of heterogenous behavior on the spread of COVID-19, both spatially and demographically. These findings could be instrumental for the design of targeted interventions for the control and mitigation of future outbreaks of COVID-19, and, more broadly, of respiratory pathogens.


Assuntos
COVID-19 , Masculino , Humanos , COVID-19/epidemiologia , China/epidemiologia , SARS-CoV-2 , Surtos de Doenças , Processos Grupais
8.
J Neurosci ; 44(7)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38124211

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by persistent deficits in social communication and stereotyped behaviors. Although major advances in basic research on autism have been achieved in the past decade, and behavioral interventions can mitigate the difficulties that individuals with autism experience, little is known about the many fundamental issues of the interventions, and no specific medication has demonstrated efficiency for the core symptoms of ASD. Intermittent hypobaric hypoxia (IHH) is characterized by repeated exposure to lowered atmospheric pressure and oxygen levels, which triggers multiple physiological adaptations in the body. Here, using two mouse models of ASD, male Shank3B -/- and Fmr1 -/y mice, we found that IHH training at an altitude of 5,000 m for 4 h per day, for 14 consecutive days, ameliorated autistic-like behaviors. Moreover, IHH training enhanced hypoxia inducible factor (HIF) 1α in the dorsal raphe nucleus (DRN) and activated the DRN serotonergic neurons. Infusion of cobalt chloride into the DRN, to mimic IHH in increasing HIF1α expression or genetically knockdown PHD2 to upregulate HIF1α expression in the DRN serotonergic neurons, alleviated autistic-like behaviors in Shank3B -/- mice. In contrast, downregulation of HIF1α in DRN serotonergic neurons induced compulsive behaviors. Furthermore, upregulating HIF1α in DRN serotonergic neurons increased the firing rates of these neurons, whereas downregulation of HIF1α in DRN serotonergic neurons decreased their firing rates. These findings suggest that IHH activated DRN serotonergic neurons via upregulation of HIF1α, and thus ameliorated autistic-like phenotypes, providing a novel therapeutic option for ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Camundongos , Masculino , Animais , Transtorno Autístico/genética , Transtorno Autístico/terapia , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/terapia , Núcleo Dorsal da Rafe , Neurônios Serotoninérgicos/fisiologia , Hipóxia , Fenótipo , Proteína do X Frágil da Deficiência Intelectual
9.
J Proteome Res ; 23(6): 2054-2066, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38775738

RESUMO

The metabolites and microbiota in tongue coating display distinct characteristics in certain digestive disorders, yet their relationship with colorectal cancer (CRC) remains unexplored. Here, we employed liquid chromatography coupled with tandem mass spectrometry to analyze the lipid composition of tongue coating using a nontargeted approach in 30 individuals with colorectal adenomas (CRA), 32 with CRC, and 30 healthy controls (HC). We identified 21 tongue coating lipids that effectively distinguished CRC from HC (AUC = 0.89), and 9 lipids that differentiated CRC from CRA (AUC = 0.9). Furthermore, we observed significant alterations in the tongue coating lipid composition in the CRC group compared to HC/CRA groups. As the adenoma-cancer sequence progressed, there was an increase in long-chain unsaturated triglycerides (TG) levels and a decrease in phosphatidylethanolamine plasmalogen (PE-P) levels. Furthermore, we noted a positive correlation between N-acyl ornithine (NAOrn), sphingomyelin (SM), and ceramide phosphoethanolamine (PE-Cer), potentially produced by members of the Bacteroidetes phylum. The levels of inflammatory lipid metabolite 12-HETE showed a decreasing trend with colorectal tumor progression, indicating the potential involvement of tongue coating microbiota and tumor immune regulation in early CRC development. Our findings highlight the potential utility of tongue coating lipid analysis as a noninvasive tool for CRC diagnosis.


Assuntos
Neoplasias Colorretais , Lipidômica , Fosfatidiletanolaminas , Espectrometria de Massas em Tandem , Língua , Humanos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Lipidômica/métodos , Masculino , Feminino , Língua/microbiologia , Língua/metabolismo , Língua/patologia , Língua/química , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Fosfatidiletanolaminas/metabolismo , Fosfatidiletanolaminas/análise , Idoso , Cromatografia Líquida , Lipídeos/análise , Lipídeos/química , Triglicerídeos/metabolismo , Triglicerídeos/análise , Adenoma/metabolismo , Adenoma/microbiologia , Esfingomielinas/análise , Esfingomielinas/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/química , Plasmalogênios/análise , Plasmalogênios/metabolismo , Plasmalogênios/química , Estudos de Casos e Controles , Etanolaminas/metabolismo , Etanolaminas/análise , Etanolaminas/química , Ceramidas/metabolismo , Ceramidas/análise , Adulto
10.
Hum Mol Genet ; 31(4): 523-534, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-34508595

RESUMO

TARS2 encodes human mitochondrial threonyl tRNA-synthetase that is responsible for generating mitochondrial Thr-tRNAThr and clearing mischarged Ser-tRNAThr during mitochondrial translation. Pathogenic variants in TARS2 have hitherto been reported in a pair of siblings and an unrelated patient with an early onset mitochondrial encephalomyopathy and a combined respiratory chain enzyme deficiency in muscle. We here report five additional unrelated patients with TARS2-related mitochondrial diseases, expanding the clinical phenotype to also include epilepsy, dystonia, hyperhidrosis and severe hearing impairment. In addition, we document seven novel TARS2 variants-one nonsense variant and six missense variants-that we demonstrate are pathogenic and causal of the disease presentation based on population frequency, homology modeling and functional studies that show the effects of the pathogenic variants on TARS2 stability and/or function.


Assuntos
Doenças Mitocondriais , Encefalomiopatias Mitocondriais , Treonina-tRNA Ligase , Humanos , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Encefalomiopatias Mitocondriais/genética , Mutação , Fenótipo , RNA de Transferência de Treonina/genética , Treonina-tRNA Ligase/genética
11.
Cancer Immunol Immunother ; 73(7): 121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714579

RESUMO

Major histocompatibility complex (MHC) could serve as a potential biomarker for tumor immunotherapy, however, it is not yet known whether MHC could distinguish potential beneficiaries. Single-cell RNA sequencing datasets derived from patients with immunotherapy were collected to elucidate the association between MHC and immunotherapy response. A novel MHCsig was developed and validated using large-scale pan-cancer data, including The Cancer Genome Atlas and immunotherapy cohorts. The therapeutic value of MHCsig was further explored using 17 CRISPR/Cas9 datasets. MHC-related genes were associated with drug resistance and MHCsig was significantly and positively associated with immunotherapy response and total mutational burden. Remarkably, MHCsig significantly enriched 6% top-ranked genes, which were potential therapeutic targets. Moreover, we generated Hub-MHCsig, which was associated with survival and disease-special survival of pan-cancer, especially low-grade glioma. This result was also confirmed in cell lines and in our own clinical cohort. Later low-grade glioma-related Hub-MHCsig was established and the regulatory network was constructed. We provided conclusive clinical evidence regarding the association between MHCsig and immunotherapy response. We developed MHCsig, which could effectively predict the benefits of immunotherapy for multiple tumors. Further exploration of MHCsig revealed some potential therapeutic targets and regulatory networks.


Assuntos
Imunoterapia , Aprendizado de Máquina , Complexo Principal de Histocompatibilidade , Neoplasias , Análise de Célula Única , Humanos , Imunoterapia/métodos , Análise de Célula Única/métodos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/imunologia , Complexo Principal de Histocompatibilidade/genética , Análise de Sequência de RNA/métodos , Biomarcadores Tumorais/genética , Prognóstico
12.
BMC Med ; 22(1): 107, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454451

RESUMO

BACKGROUND: Classical Hodgkin lymphoma (cHL) is a highly curable disease, while novel therapy is needed for refractory or relapsed (R/R) patients. This phase II trial aimed to evaluate the role of camrelizumab plus gemcitabine and oxaliplatin (GEMOX) in R/R cHL patients. METHODS: Transplant-eligible patients with R/R cHL were enrolled and received two 14-day cycles of camrelizumab 200 mg intravenously (IV) and two 28-day cycles of camrelizumab 200 mg IV, gemcitabine 1000 mg/m2 IV, and oxaliplatin 100 mg/m2 IV on days 1 and 15. Patients with partial response (PR) or stable disease received an additional cycle of combination therapy. Those who achieved complete response (CR) or PR proceeded to autologous stem cell transplantation (ASCT). The primary endpoint was the CR rate at the end of protocol therapy before ASCT. RESULTS: Forty-two patients were enrolled. At the end of protocol therapy, the objective response rate and CR rate were 94.9% (37/39) and 69.2% (27/39) in the evaluable set, and 88.1% (37/42) and 64.3% (27/42) in the full analysis set, respectively. Twenty-nine patients (69.0%) proceeded to ASCT, and 4 of 5 patients with PR achieved CR after ASCT. After a median follow-up of 20.7 months, the 12-month progression-free survival rate was 96.6% and the 12-month overall survival rate was 100%. Grade 3 or higher treatment emergent adverse events occurred in 28.6% of patients (12/42), mainly hematological toxicity. CONCLUSIONS: Camrelizumab combined with GEMOX constitutes an effective salvage therapy for R/R cHL, proving to be relatively well-tolerated and facilitating ASCT in most patients, thus promoting sustained remission. TRIAL REGISTRATION: ClinicalTrials.gov NCT04239170. Registered on January 1, 2020.


Assuntos
Anticorpos Monoclonais Humanizados , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin , Humanos , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/etiologia , Doença de Hodgkin/patologia , Gencitabina , Oxaliplatina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Transplante Autólogo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resultado do Tratamento
13.
Small ; 20(10): e2306140, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875718

RESUMO

The shuttle effect and sluggish redox kinetics of lithium polysulfides (LiPSs) severely hinder the scalable application of lithium-sulfurr (Li-S) batteries. Herein, the highly dispersed α-phase molybdenum carbide nano-crystallites embedded in a porous nitrogen-doped carbon framework (α-MoC1-x @NCF) are developed via a simple metal-organic frameworks (MOFs) assisted strategy and proposed as the multifunctional separator interlayer for Li-S batteries. The inlaid MoC1-x nanocrystals and in situ doped nitrogen atoms provide a strong chemisorption and outstanding electrocatalytic conversion toward LiPSs, whereas the unique plum-like carbon framework with hierarchical porosity enables fast electron/Li+ transfer and can physically suppress LiPSs shuttling. Benefiting from the synergistic trapping-catalyzing effect of the MoC1-x @NCF interlayer toward LiPSs, the assembled Li-S battery achieves high discharge capacities (1588.1 mAh g-1 at 0.1 C), impressive rate capability (655.8 mAh g-1 at 4.0 C) and ultra-stable lifespan (a low capacity decay of 0.059% per cycle over 650 cycles at 1.0 C). Even at an elevated sulfur loading (6.0 mg cm-2 ) and lean electrolyte (E/S is ≈5.8 µL mg-1 ), the battery can still achieve a superb areal capacity of 5.2 mAh cm-2 . This work affords an effective design strategy for the construction of muti-functional interlayer in advanced Li-S batteries.

14.
Small ; : e2400985, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693073

RESUMO

Ionic liquids have been widely used to improve the efficiency and stability of perovskite solar cells (PSCs), and are generally believed to passivate defects on the grain boundaries of perovskites. However, few studies have focused on the relevant effects of ionic liquids on intragrain defects in perovskites which have been shown to be critical for the performance of PSCs. In this work, the effect of ionic liquid 1-hexyl-3-methylimidazolium iodide (HMII) on intragrain defects of formamidinium lead iodide (FAPbI3) perovskite is investigated. Abundant {111}c intragrain planar defects in pure FAPbI3 grains are found to be significantly reduced by the addition of the ionic liquid HMII, shown by using ultra-low-dose selected area electron diffraction. As a result, longer charge carrier lifetimes, higher photoluminescence quantum yield, better charge carrier transport properties, lower Urbach energy, and current-voltage hysteresis are achieved, and the champion power conversion efficiency of 24.09% is demonstrated. These observations suggest that ionic liquids significantly improve device performance resulting from the elimination of {111}c intragrain planar defects.

15.
Chembiochem ; 25(13): e202400001, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38720172

RESUMO

Coronavirus (CoV) infections have caused contagious and fatal respiratory diseases in humans worldwide. CoV 3-chymotrypsin-like proteases (3CLpro or Mpro) play an important role in viral maturation, and maintenance of their dimeric conformation is crucial for viral activity. Therefore, allosterically regulated dimerization of 3CLpro can be employed as a drug development target. Here, we investigated the allosteric regulatory mechanism of 3CLpro dimerization by using hydrogen/deuterium exchange coupled with mass spectrometry (HDX-MS) technology. We found that the FLAG tag directly coupled to the N-finger of 3CLpro significantly increased HDX kinetics at the dimer interface, and 3CLpro transformed from a dimer to a monomer. The 3CLpro mutants of SARS-CoV-2, which are monomeric, also exhibited increased deuterium exchange. Binding of the allosteric inhibitor Gastrodenol to most betacoronavirus 3CLpros led to increased allosteric deuterium exchange, resulting in the monomeric conformation of the CoV 3CLpro upon binding. Molecular dynamics (MD) simulation analysis further indicated the molecular mechanism of action of Gastrodenol on CoV 3CLpro: binding of Gastrodenol to SARS-CoV-2 3CLpro destroyed the hydrogen bond in the dimer interface. These results suggest that Gastrodenol may be a potential broad-spectrum anti-betacoronavirus drug.


Assuntos
Proteases 3C de Coronavírus , Espectrometria de Massa com Troca Hidrogênio-Deutério , Simulação de Dinâmica Molecular , SARS-CoV-2 , Regulação Alostérica/efeitos dos fármacos , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , SARS-CoV-2/enzimologia , SARS-CoV-2/efeitos dos fármacos , Humanos , Multimerização Proteica/efeitos dos fármacos , Cinética , Medição da Troca de Deutério
16.
Crit Care Med ; 52(6): e268-e278, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38441040

RESUMO

OBJECTIVE: Comparing the effects of extracorporeal cardiopulmonary resuscitation (ECPR) and conventional cardiopulmonary resuscitation (CCPR) on outcomes in patients with in-hospital cardiac arrest (IHCA) in China. The benefits of ECPR over CCPR in patients with IHCA remain controversial. DESIGN: This article analyzed data from the BASeline Investigation of In-hospital Cardiac Arrest (BASIC-IHCA) study, which consecutively enrolled patients with IHCA from July 1, 2019, to December 31, 2020. Patients who received ECPR were selected as the case group and matched with patients who received CCPR as the control group by propensity score at a ratio of 1:4. A parallel questionnaire survey of participating hospitals was conducted, to collect data on ECPR cases from January 1, 2021 to November 30, 2021. The primary outcome was survival to discharge or 30-day survival. SETTING: We included 39 hospitals across 31 provinces in China. PATIENTS: Patients receiving cardiopulmonary resuscitation and without contraindications to ECPR were selected from the BASIC-IHCA database. Patients older than 75 years, not witnessed, or with cardiopulmonary resuscitation duration less than 10 min were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 4853 patients met the inclusion criteria before matching, with 34 undergoing ECPR (median age, 56.5 yr; 67.65% male) and 4819 underwent CCPR (median age, 59 yr; 64.52% male). There were 132 patients receiving CCPR and 33 patients receiving ECPR who were eventually matched. The ECPR group had significantly higher survival rates at discharge or 30-day survival (21.21% vs. 7.58%, p = 0.048). The ECPR group had significantly lower mortality rates (hazard ratio 0.57; 95% CI, 0.38-0.91) than the CCPR group at discharge or 30 days. Besides the BASIC-IHCA study, the volume of ECPR implementations and the survival rate of patients with ECPR (29.4% vs. 10.4%. p = 0.004) in participating hospitals significantly improved. CONCLUSIONS: ECPR may be beneficial compared with CCPR for patient survival after IHCA and should be considered for eligible patients with IHCA.


Assuntos
Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Pontuação de Propensão , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Reanimação Cardiopulmonar/métodos , Parada Cardíaca/terapia , Parada Cardíaca/mortalidade , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/mortalidade , China/epidemiologia , Idoso , Estudos de Coortes , Adulto , Mortalidade Hospitalar
17.
Cytokine ; 179: 156618, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38663252

RESUMO

BACKGROUND: Pleural biomarkers represent potential diagnostic tools for tuberculous pleural effusion (TPE) due to their advantages of low cost, short turnaround time, and less invasiveness. This study evaluated the diagnostic accuracy of two CXCR3 ligands, C-X-C motif chemokine ligand 9 (CXCL9) and CXCL11, for TPE. In addition, we investigated the cellular origins and biological roles of CXCL9 and CXCL11 in the development of TPE. METHODS: This double-blind study prospectively enrolled patients with undiagnosed pleural effusion from two centers (Hohhot and Changshu) in China. Pleural fluid on admission was obtained and levels of CXCL9 and CXCL11 were measured by an enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve and the decision curve analysis (DCA) were used to evaluate their diagnostic accuracy and net benefit, respectively. THP-1 cell-derived macrophages were treated with Bacillus Calmette-Guérin (BCG), and quantitative real-time PCR (qRT-PCR) and ELISA were used to determine the mRNA and protein levels of CXCL9 and CXCL11. The chemoattractant activities of CXCL9 and CXCL11 for T helper (Th) cells were analyzed by a transwell assay. RESULTS: One hundred and fifty-three (20 TPEs and 133 non-TPEs) patients were enrolled in the Hohhot Center, and 58 (13 TPEs and 45 non-TPEs) were enrolled in the Changshu Center. In both centers, we observed increased CXCL9 and CXCL11 in TPE patients. The areas under the ROC curves (AUCs) of pleural CXCL9 and CXCL11 in the Hohhot Center were 0.70 (95 % CI: 0.55-0.85) and 0.68 (95 % CI: 0.52-0.84), respectively. In the Changshu Center, the AUCs of CXCL9 and CXCL11 were 0.96 (95 % CI: 0.92-1.00) and 0.97 (95 % CI: 0.94-1.00), respectively. The AUCs of CXCL9 and CXCL11 decreased with the advancement of age. The decision curves of CXCL9 and CXCL11 showed net benefits in both centers. CXCL9 and CXCL11 were upregulated in BCG-treated macrophages. Pleural fluid from TPE and conditioned medium from BCG-treated macrophages were chemotactic for Th cells. Anti-CXCL9 or CXCL11 neutralizing antibodies could partly block the chemotactic activity. CONCLUSIONS: Pleural CXCL9 and CXCL11 are potential diagnostic markers for TPE, but their diagnostic accuracy is compromised in elderly patients. CXCL9 and CXCL11 can promote the migration of peripheral Th cells, thus representing a therapeutic target for the treatment of TPE.


Assuntos
Quimiocina CXCL11 , Quimiocina CXCL9 , Derrame Pleural , Receptores CXCR3 , Tuberculose Pleural , Humanos , Quimiocina CXCL9/metabolismo , Quimiocina CXCL11/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Derrame Pleural/metabolismo , Derrame Pleural/diagnóstico , Receptores CXCR3/metabolismo , Tuberculose Pleural/diagnóstico , Tuberculose Pleural/metabolismo , Adulto , Ligantes , Método Duplo-Cego , Células THP-1 , Biomarcadores/metabolismo , Macrófagos/metabolismo , Estudos Prospectivos , Idoso , Curva ROC
18.
Reproduction ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38941177

RESUMO

There has been remarkable progress in the conservation and reproduction of giant pandas. However, the physiology of the gestation period in pandas remains poorly understood. The metabolic processes from estrus to pregnancy are dynamic and precisely regulated, playing a crucial role in pregnancy and related dysfunctions. In this study, we conducted a metabolomic analysis of 37 blood samples collected from pandas in estrus, acyclic, potential pregnant states, employing rigorous screening to minimize the influence of diet. Our findings suggest that a reduced appetite can serve as an indicator for evaluating implantation time, representing a characteristic response to pregnancy and aiding in the prediction of delivery time in pregnant pandas. Metabolomic results indicate great metabolism variation from estrus to pregnancy, and highlight the association between amino acid metabolism and pregnancy outcomes. Compared to other pandas, individuals which successfully bred exhibit significantly elevated levels of arginine and histidine, even 2 months before experiencing reduced appetite. Furthermore, the lipid profile undergoes distinct dynamic changes only in estrus samples. In summary, our study comprehensively characterizes the metabolism of giant pandas during gestation and proposes arginine and histidine as potential novel biomarkers for detecting the pregnancy state of giant pandas.

19.
J Magn Reson Imaging ; 59(2): 548-560, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37222658

RESUMO

BACKGROUND: It is uncertain how various degree of glycemic status affect left ventricular (LV) myocardial strain in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). PURPOSE: To investigate the relationship of glycemic status and myocardial strain in STEMI patients. STUDY TYPE: Prospective cohort study. POPULATION: 282 STEMI patients with cardiac magnetic resonance imaging 5 ± 2 days post-PPCI. Patients were divided into three groups based on the level of glycated hemoglobin A1c (HbA1c) (group 1: HbA1c < 5.7%; group 2: 5.7% ≤ HbA1c < 6.5%; group 3: HbA1c ≥ 6.5%). FIELD STRENGTH/SEQUENCE: 3.0-T; late gadolinium enhancement, balanced steady-state free precession cine sequence, black blood fat-suppressed T2-weighted. ASSESSMENT: LV function, myocardial strain, and infarct characteristics (infarct size, microvascular obstruction, and intramyocardial hemorrhage) were compared among the three groups by one-way analysis of variance (ANOVA) or Wilcoxon rank sum test. Intraobserver and interobserver reproducibility of LV myocardial strain was evaluated. STATISTICAL TESTS: ANOVA or Wilcoxon rank sum test, Pearson chi-square or Fisher's exact test, Spearman's correlation analyses and multivariable linear regression analysis. A two-tailed P value <0.05 was considered statistically significant. RESULTS: Infarct characteristics were similar among the three groups (P = 0.934, P = 0.097, P = 0.533, respectively). Patients with HbA1c ≥ 6.5% had decreased LV myocardial strain compared with HbA1c 5.7%-6.4%, as evidenced by global radial (GRS), global circumferential (GCS), and global longitudinal (GLS) strain. However, no significant differences in myocardial strain were observed between patients with HbA1c 5.7%-6.4% and HbA1c < 5.7% (P = 0.716; P = 0.294; P = 0.883, respectively). After adjustment for confounders, HbA1c as a continuous variable (beta coefficient [ß] = -0.676; ß = 0.172; ß = 0.205, respectively) and HbA1c ≥ 6.5% (ß = -3.682; ß = 0.552; ß = 0.681, respectively) were both independently associated with decreased GRS, GCS, and GLS. DATA CONCLUSION: Patients with uncontrolled blood glucose (categorized in group HbA1c ≥ 6.5%) had worse myocardial strain. The level of HbA1c appeared to be independently associated with decreased myocardial strain in STEMI patients. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Meios de Contraste , Resultado do Tratamento , Estudos Prospectivos , Reprodutibilidade dos Testes , Hemoglobinas Glicadas , Imagem Cinética por Ressonância Magnética , Gadolínio , Imageamento por Ressonância Magnética , Função Ventricular Esquerda , Volume Sistólico
20.
Pediatr Res ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548969

RESUMO

BACKGROUND: Overnutrition in early life increases the risk of obesity and metabolic diseases. We investigated the effects and the window period of a curcumin (CUR) diet on postnatal overfed rats. METHODS: Male rats aged 3 days were randomly divided into normal litters (NL, 10 pups/litter) and small litters (SL, 3 pups/litter). After weaning (Week 3, W3), NL rats were fed a normal diet (NL) and SL rats were fed a normal diet (SL) or 2% CUR diet from weaning (W3) (SL-CURW13), beginning of puberty (W6) (SL-CURW16), or end of puberty (W8) (SL-CURW18) for 10 weeks. RESULTS: Body weight, glucose intolerance and hyperlipidemia in the SL rats were higher than in the NL rats, especially after puberty. After the CUR intervention, SL-CURW13 and SL-CURW16 rats showed lower body weight gain, adipose tissue weight and mRNA level of C/EBPα in SAT, along with higher mRNA levels of ß-catenin. There was no difference between SL and SL-CURW18 rats. Glucose tolerance, serum lipids and hepatic lipids recovered to normal in the SL-CURW13 rats, but only partially in the SL-CURW16 and SL-CURW18 rats. CONCLUSION: Prepuberty is a window period for CUR intervention to improve programmed outcomes in postnatal overfed rats. IMPACT: Overnutrition during the first 1000 days of life has persistent negative effects on metabolism. Strategies should be taken to prevent overnutrition in early life to reduce the risk of obesity and metabolic disease in later life. A small-litter rat model was utilized to simulate early-life overnutrition in humans. We investigated the different effects and critical period for curcumin intervention on postnatal overfed rats. Dietary curcumin intervention before puberty could effectively transform nutritional programming to reduce obesity and metabolic disorders caused by early-life overnutrition, and an earlier intervention might predict a better outcome.

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