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1.
Immunity ; 54(10): 2321-2337.e10, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34582748

RESUMO

Hair follicles (HFs) function as hubs for stem cells, immune cells, and commensal microbes, which must be tightly regulated during homeostasis and transient inflammation. Here we found that transmembrane endopeptidase ADAM10 expression in upper HFs was crucial for regulating the skin microbiota and protecting HFs and their stem cell niche from inflammatory destruction. Ablation of the ADAM10-Notch signaling axis impaired the innate epithelial barrier and enabled Corynebacterium species to predominate the microbiome. Dysbiosis triggered group 2 innate lymphoid cell-mediated inflammation in an interleukin-7 (IL-7) receptor-, S1P receptor 1-, and CCR6-dependent manner, leading to pyroptotic cell death of HFs and irreversible alopecia. Double-stranded RNA-induced ablation models indicated that the ADAM10-Notch signaling axis bolsters epithelial innate immunity by promoting ß-defensin-6 expression downstream of type I interferon responses. Thus, ADAM10-Notch signaling axis-mediated regulation of host-microbial symbiosis crucially protects HFs from inflammatory destruction, which has implications for strategies to sustain tissue integrity during chronic inflammation.


Assuntos
Proteína ADAM10/imunologia , Secretases da Proteína Precursora do Amiloide/imunologia , Disbiose/imunologia , Folículo Piloso/patologia , Linfócitos/imunologia , Proteínas de Membrana/imunologia , Receptores Notch/imunologia , Pele/microbiologia , Alopecia/imunologia , Alopecia/patologia , Animais , Corynebacterium , Disbiose/patologia , Feminino , Folículo Piloso/imunologia , Imunidade Inata , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Transdução de Sinais/imunologia , Pele/imunologia , Pele/patologia
2.
Nano Lett ; 24(18): 5578-5584, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682925

RESUMO

The lattice parameter of platinum-based intermetallic compounds (IMCs), which correlates with the intrinsic activity of the oxygen reduction reaction (ORR), can be modulated by crystal phase engineering. However, the controlled preparation of IMCs with unconventional crystal structures remains highly challenging. Here, we demonstrate the synthesis of carbon-supported PtCu-based IMC catalysts with an unconventional L10 structure by a composition-regulated strategy. Experiment and machine learning reveal that the thermodynamically favorable structure changes from L11 to L10 when slight Cu atoms are substituted with Co. Benefiting from crystal-phase-induced strain enhancement, the prepared L10-type PtCu0.8Co0.2 catalyst exhibits much-enhanced mass and specific activities of 1.82 A mgPt-1 and 3.27 mA cmPt-2, which are 1.91 and 1.73 times higher than those of the L11-type PtCu catalyst, respectively. Our work highlights the important role of crystal phase in determining the surface strain of IMCs, and opens a promising avenue for the rational preparation of IMCs with different crystal phases by doping.

3.
J Am Chem Soc ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592685

RESUMO

The determination of catalytically active sites is crucial for understanding the catalytic mechanism and providing guidelines for the design of more efficient catalysts. However, the complex structure of supported metal nanocatalysts (e.g., support, metal surface, and metal-support interface) still presents a big challenge. In particular, many studies have demonstrated that metal-support interfaces could also act as the primary active sites in catalytic reactions, which is well elucidated in oxide-supported metal nanocatalysts but is rarely reported in carbon-supported metal nanocatalysts. Here, we fill the above gap and demonstrate that metal-sulfur interfaces in sulfur-doped carbon-supported metal nanocatalysts are the primary active sites for several catalytic hydrogenation reactions. A series of metal nanocatalysts with similar sizes but different amounts of metal-sulfur interfaces were first constructed and characterized. Taking Ir for quinoline hydrogenation as an example, it was found that their catalytic activities were proportional to the amount of the Ir-S interface. Further experiments and density functional theory (DFT) calculations suggested that the adsorption and activation of quinoline occurred on the Ir atoms at the Ir-S interface. Similar phenomena were found in p-chloronitrobenzene hydrogenation over the Pt-S interface and benzoic acid hydrogenation over the Ru-S interface. All of these findings verify the predominant activity of metal-sulfur interfaces for catalytic hydrogenation reactions and contribute to the comprehensive understanding of metal-support interfaces in supported nanocatalysts.

4.
J Hepatol ; 81(3): 389-403, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38670321

RESUMO

BACKGROUND & AIMS: The precise pathomechanisms underlying the development of non-alcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. In this study, we investigated the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in the pathogenesis of NASH. METHODS: Hepatic EFHD2 expression was characterized in patients with NASH and two diet-induced NASH mouse models. Single-cell RNA sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma were assessed. Molecular mechanisms underlying EFHD2 function were investigated, while chemical and genetic investigations were performed to assess its potential as a therapeutic target. RESULTS: EFHD2 expression was significantly elevated in hepatic macrophages/monocytes in both patients with NASH and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related hepatocellular carcinoma. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of IFNγR2 (interferon-γ receptor-2) onto the plasma membrane. This interaction mediates interferon-γ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a novel stapled α-helical peptide targeting EFHD2 was shown to be effective in protecting against NASH pathology in mice. CONCLUSION: Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment. IMPACT AND IMPLICATIONS: Non-alcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all patients with NAFLD progress to NASH. A key challenge is identifying the factors that trigger inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of interferon-γ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings support the potential of EFHD2 as a therapeutic target in NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/etiologia , Modelos Animais de Doenças , Ferroptose/efeitos dos fármacos , Interferon gama/metabolismo , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Macrófagos/metabolismo , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/imunologia
5.
Small ; 20(40): e2401134, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38816761

RESUMO

Strain engineering has been widely used to optimize platinum-based oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs). PtM3 (M is base metals), a well-known high-compressive-strain intermetallic alloy, shows promise as a low platinum ORR catalyst due to high intrinsic activity. However, during the alloying of Pt with a threefold amount of M, a notable phase separation between Pt and M may occur, with M particles rapidly sintering while Pt particles grow slowly, posing a challenge in achieving a well-defined PtM3 intermetallic alloy. Here, an entropy-driven Ostwald ripening reversal phenomenon is discovered that enables the synthesis of small-sized Pt(FeCoNiCu)3 intermetallic ORR catalysts. High entropy promotes the thermodynamic driving force for the alloying Pt with M, which triggers the Ostwald ripening reversal of sintered FeCoNiCu particles and facilitates the formation of uniform Pt(FeCoNiCu)3 intermetallic catalysts. The prepared Pt(FeCoNiCu)3 catalysts exhibit a high specific activity of 3.82 mA cm-2, along with a power density of ≈1.3 W cm-2 at 0.67 V and 94 °C with a cathode Pt loading of 0.1 mg cm-2 in H2-air fuel cell.

6.
Nat Mater ; 22(1): 100-108, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36266572

RESUMO

Iridium-based electrocatalysts remain the only practical anode catalysts for proton exchange membrane (PEM) water electrolysis, due to their excellent stability under acidic oxygen evolution reaction (OER), but are greatly limited by their high cost and low reserves. Here, we report a nickel-stabilized, ruthenium dioxide (Ni-RuO2) catalyst, a promising alternative to iridium, with high activity and durability in acidic OER for PEM water electrolysis. While pristine RuO2 showed poor acidic OER stability and degraded within a short period of continuous operation, the incorporation of Ni greatly stabilized the RuO2 lattice and extended its durability by more than one order of magnitude. When applied to the anode of a PEM water electrolyser, our Ni-RuO2 catalyst demonstrated >1,000 h stability under a water-splitting current of 200 mA cm-2, suggesting potential for practical applications. Density functional theory studies, coupled with operando differential electrochemical mass spectroscopy analysis, confirmed the adsorbate-evolving mechanism on Ni-RuO2, as well as the critical role of Ni dopants in stabilization of surface Ru and subsurface oxygen for improved OER durability.

7.
Rheumatology (Oxford) ; 63(2): 571-580, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37228024

RESUMO

OBJECTIVES: Endothelial protein C receptor (EPCR) is highly expressed in synovial tissues of patients with RA, but the function of this receptor remains unknown in RA. This study investigated the effect of EPCR on the onset and development of inflammatory arthritis and its underlying mechanisms. METHODS: CIA was induced in EPCR gene knockout (KO) and matched wild-type (WT) mice. The onset and development of arthritis was monitored clinically and histologically. T cells, dendritic cells (DCs), EPCR and cytokines from EPCR KO and WT mice, RA patients and healthy controls (HCs) were detected by flow cytometry and ELISA. RESULTS: EPCR KO mice displayed >40% lower arthritis incidence and 50% less disease severity than WT mice. EPCR KO mice also had significantly fewer Th1/Th17 cells in synovial tissues with more DCs in circulation. Lymph nodes and synovial CD4 T cells from EPCR KO mice expressed fewer chemokine receptors CXCR3, CXCR5 and CCR6 than WT mice. In vitro, EPCR KO spleen cells contained fewer Th1 and more Th2 and Th17 cells than WT and, in concordance, blocking EPCR in WT cells stimulated Th2 and Th17 cells. DCs generated from EPCR KO bone marrow were less mature and produced less MMP-9. Circulating T cells from RA patients expressed higher levels of EPCR than HC cells; blocking EPCR stimulated Th2 and Treg cells in vitro. CONCLUSION: Deficiency of EPCR ameliorates arthritis in CIA via inhibition of the activation and migration of pathogenic Th cells and DCs. Targeting EPCR may constitute a novel strategy for future RA treatment.


Assuntos
Artrite Experimental , Artrite Reumatoide , Animais , Humanos , Camundongos , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Células Dendríticas/metabolismo , Receptor de Proteína C Endotelial/metabolismo , Membrana Sinovial/patologia , Células Th17/metabolismo
8.
Cell Mol Neurobiol ; 44(1): 50, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856921

RESUMO

In recent years, spatial transcriptomics (ST) research has become a popular field of study and has shown great potential in medicine. However, there are few bibliometric analyses in this field. Thus, in this study, we aimed to find and analyze the frontiers and trends of this medical research field based on the available literature. A computerized search was applied to the WoSCC (Web of Science Core Collection) Database for literature published from 2006 to 2023. Complete records of all literature and cited references were extracted and screened. The bibliometric analysis and visualization were performed using CiteSpace, VOSviewer, Bibliometrix R Package software, and Scimago Graphica. A total of 1467 papers and reviews were included. The analysis revealed that the ST publication and citation results have shown a rapid upward trend over the last 3 years. Nature Communications and Nature were the most productive and most co-cited journals, respectively. In the comprehensive global collaborative network, the United States is the country with the most organizations and publications, followed closely by China and the United Kingdom. The author Joakim Lundeberg published the most cited paper, while Patrik L. Ståhl ranked first among co-cited authors. The hot topics in ST are tissue recognition, cancer, heterogeneity, immunotherapy, differentiation, and models. ST technologies have greatly contributed to in-depth research in medical fields such as oncology and neuroscience, opening up new possibilities for the diagnosis and treatment of diseases. Moreover, artificial intelligence and big data drive additional development in ST fields.


Assuntos
Bibliometria , Transcriptoma , Humanos , Transcriptoma/genética , Publicações , Animais
9.
Acta Pharmacol Sin ; 45(7): 1425-1437, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38839936

RESUMO

Cardiac fibrosis is a pathological scarring process that impairs cardiac function. N-acetyltransferase 10 (Nat10) is recently identified as the key enzyme for the N4-acetylcytidine (ac4C) modification of mRNAs. In this study, we investigated the role of Nat10 in cardiac fibrosis following myocardial infarction (MI) and the related mechanisms. MI was induced in mice by ligation of the left anterior descending coronary artery; cardiac function was assessed with echocardiography. We showed that both the mRNA and protein expression levels of Nat10 were significantly increased in the infarct zone and border zone 4 weeks post-MI, and the expression of Nat10 in cardiac fibroblasts was significantly higher compared with that in cardiomyocytes after MI. Fibroblast-specific overexpression of Nat10 promoted collagen deposition and induced cardiac systolic dysfunction post-MI in mice. Conversely, fibroblast-specific knockout of Nat10 markedly relieved cardiac function impairment and extracellular matrix remodeling following MI. We then conducted ac4C-RNA binding protein immunoprecipitation-sequencing (RIP-seq) in cardiac fibroblasts transfected with Nat10 siRNA, and revealed that angiomotin-like 1 (Amotl1), an upstream regulator of the Hippo signaling pathway, was the target gene of Nat10. We demonstrated that Nat10-mediated ac4C modification of Amotl1 increased its mRNA stability and translation in neonatal cardiac fibroblasts, thereby increasing the interaction of Amotl1 with yes-associated protein 1 (Yap) and facilitating Yap translocation into the nucleus. Intriguingly, silencing of Amotl1 or Yap, as well as treatment with verteporfin, a selective and potent Yap inhibitor, attenuated the Nat10 overexpression-induced proliferation of cardiac fibroblasts and prevented their differentiation into myofibroblasts in vitro. In conclusion, this study highlights Nat10 as a crucial regulator of myocardial fibrosis following MI injury through ac4C modification of upstream activators within the Hippo/Yap signaling pathway.


Assuntos
Fibrose , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Animais , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Camundongos , Masculino , Proteínas de Sinalização YAP/metabolismo , Fibroblastos/metabolismo , Citidina/análogos & derivados , Citidina/farmacologia , Camundongos Knockout , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Acetiltransferase N-Terminal E/metabolismo , Via de Sinalização Hippo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Células Cultivadas , Transdução de Sinais , Acetiltransferases N-Terminal/metabolismo , Miocárdio/patologia , Miocárdio/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
10.
Environ Res ; 251(Pt 2): 118719, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490622

RESUMO

In southern China, winter green manure is widely used in rice cropping systems for improving grain yields and soil fertility. Cd pollution has recently been reported in some of these paddy fields. Research on the in-depth understanding of how green manuring affects Cd absorption in rice is limited. This study aimed to investigate the impacts of different green manures, including single plantation and mixed plantation on the absorption of Cd by rice and explore the underlying mechanisms. Pot experiments demonstrated that compared with winter fallow-rice, green manuring treatments considerably decreased rice Cd content, promoted the conversion of bioavailable Cd fraction into a more stable form, induced the formation of iron plaque, and increased the content of humic-like fraction (HF) in soil dissolved organic matter (DOM). Treatment with mixed plantation resulted in a greater decrease in rice Cd content and an increase in HF and iron plaque contents than single plantation. Hydroponic experiments confirmed that both iron plaque and green manure-derived DOM significantly reduced the Cd content in rice seedlings. In conclusion, green manure incorporation is an efficient measure for the safe utilization of Cd-contaminated soil, and mixed plantation of different green manures exerts stronger effects.


Assuntos
Cádmio , Ferro , Esterco , Oryza , Poluentes do Solo , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Cádmio/análise , Cádmio/metabolismo , Ferro/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Esterco/análise , China , Agricultura/métodos , Substâncias Húmicas/análise , Solo/química
11.
BMC Musculoskelet Disord ; 25(1): 796, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385153

RESUMO

OBJECTIVE: This study aimed to evaluate the effectiveness of combined core decompression (CD), bone grafting (BG), and platelet-rich plasma (PRP) in treating early-stage avascular necrosis of the femoral head (ANFH). METHODS: A retrospective study was conducted on 74 patients (85 hips) with Ficat-Arlet stage I-II ANFH who were treated at our hospital between May 2015 and May 2018. The control group (20 patients, 22 hips) received symptomatic treatments, including weight-bearing reduction and oral analgesics. The CD + BG group (29 patients, 34 hips) underwent CD and ß-tricalcium phosphate bone grafting. The PRP combination group (25 patients, 29 hips) received PRP injections in addition to CD and BG. Patients were followed up for five years to assess the necessity for total hip arthroplasty (THA). Data analysis was performed on those from the CD + BG and PRP groups who did not require THA. Clinical outcomes were evaluated using the Visual Analog Scale (VAS), Harris Hip Score (HHS), and the proportion of patients not accepting THA. RESULTS: At the five-year follow-up, the rate of THA in the control group was 68.18% (15/22), while in the CD + BG group and the PRP combination group, the rates were 17.65% (6/34) and 10.34% (3/29), respectively. There was no statistically significant difference between the CD + BG group and the PRP combination group (P = 0.441), but both differed significantly from the control group (P < 0.001). Kaplan-Meier survival analysis showed that over time, the proportion of patients in the PRP combination group who did not require THA was consistently higher than that in the CD + BG group. Among patients who did not undergo THA, the proportion of Ficat-Arlet stage I-II patients in the PRP combination group was 88.46% (23/26), which was higher than the 64.29% (18/28) in the CD + BG group, showing a significant difference (P = 0.038). VAS score and HHS were compared between the two groups at 6 months, 12 months, and the last follow-up point, with patients in the PRP combination group showing better scores than those in the CD + BG group (p < 0.05) in both metrics. CONCLUSION: The combination therapy of CD, BG, and PRP demonstrates significant advantages in improving symptoms and delaying disease progression in early-stage ANFH.


Assuntos
Transplante Ósseo , Descompressão Cirúrgica , Necrose da Cabeça do Fêmur , Plasma Rico em Plaquetas , Humanos , Necrose da Cabeça do Fêmur/cirurgia , Necrose da Cabeça do Fêmur/terapia , Estudos Retrospectivos , Feminino , Masculino , Transplante Ósseo/métodos , Adulto , Descompressão Cirúrgica/métodos , Pessoa de Meia-Idade , Resultado do Tratamento , Terapia Combinada , Seguimentos , Adulto Jovem , Artroplastia de Quadril/métodos
12.
BMC Surg ; 24(1): 157, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755649

RESUMO

BACKGROUND: Fractures involving the posterior acetabulum with its rich vascular and neural supply present challenges in trauma orthopedics. This study evaluates the effectiveness of 3D printing technology with the use of custom-made metal plates in the treatment of posterior wall and column acetabular fractures. METHODS: A retrospective analysis included 31 patients undergoing surgical fixation for posterior wall and column fractures of the acetabulum (16 in the 3D printing group, utilizing 3D printing for a 1:1 pelvic model and custom-made plates based on preoperative simulation; 15 in the traditional group, using conventional methods). Surgical and instrument operation times, intraoperative fluoroscopy frequency, intraoperative blood loss, fracture reduction quality, fracture healing time, preoperative and 12-month postoperative pain scores (Numeric Rating Scale, NRS), hip joint function at 6 and 12 months (Harris scores), and complications were compared. RESULTS: The surgical and instrument operation times were significantly shorter in the 3D printing group (p < 0.001). The 3D printing group exhibited significantly lower intraoperative fluoroscopy frequency and blood loss (p = 0.001 and p < 0.001, respectively). No significant differences were observed between the two groups in terms of fracture reduction quality, fracture healing time, preoperative pain scores (NRS scores), and 6-month hip joint function (Harris scores) (p > 0.05). However, at 12 months, hip joint function and pain scores were significantly better in the 3D printing group (p < 0.05). Although the incidence of complications was lower in the 3D printing group (18.8% vs. 33.3%), the difference did not reach statistical significance (p = 0.433). CONCLUSION: Combining 3D printing with individualized custom-made metal plates for acetabular posterior wall and column fractures reduces surgery and instrument time, minimizes intraoperative procedures and blood loss, enhancing long-term hip joint function recovery. CLINICAL TRIAL REGISTRATION: 12/04/2023;Trial Registration No. ChiCTR2300070438; http://www.chictr.org.cn .


Assuntos
Acetábulo , Placas Ósseas , Fixação Interna de Fraturas , Fraturas Ósseas , Impressão Tridimensional , Humanos , Estudos Retrospectivos , Acetábulo/cirurgia , Acetábulo/lesões , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Resultado do Tratamento , Fraturas Ósseas/cirurgia , Duração da Cirurgia , Adulto Jovem , Desenho de Prótese , Idoso
13.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279255

RESUMO

Endothelial protein C receptor (EPCR) is a receptor for the natural anti-coagulant activated protein C (aPC). It mediates the anti-inflammatory and barrier-protective functions of aPC through the cleavage of protease-activated receptor (PAR)1/2. Allergic contact dermatitis is a common skin disease characterized by inflammation and defective skin barrier. This study investigated the effect of EPCR and 3K3A-aPC on allergic contact dermatitis using a contact hypersensitivity (CHS) model. CHS was induced using 1-Fluoro-2,4-dinitrobenzene in EPCR-deficient (KO) and matched wild-type mice and mice treated with 3K3A-aPC, a mutant form of aPC with diminished anti-coagulant activity. Changes in clinical and histological features, cytokines, and immune cells were examined. EPCRKO mice displayed more severe CHS, with increased immune cell infiltration in the skin and higher levels of inflammatory cytokines and IgE than wild-type mice. EPCR, aPC, and PAR1/2 were expressed by the skin epidermis, with EPCR presenting almost exclusively in the basal layer. EPCRKO increased the epidermal expression of aPC and PAR1, whereas in CHS, their expression was reduced compared to wild-type mice. 3K3A-aPC reduced CHS severity in wild-type and EPCRKO mice by suppressing immune cell infiltration/activation and inflammatory cytokines. In summary, EPCRKO exacerbated CHS, whereas 3K3A-aPC could reduce the severity of CHS in both EPCRKO and wild-type mice.


Assuntos
Dermatite Alérgica de Contato , Proteína C , Proteínas Recombinantes , Animais , Camundongos , Proteína C/metabolismo , Receptor de Proteína C Endotelial/metabolismo , Receptor PAR-1/metabolismo , Transdução de Sinais , Citocinas/farmacologia , Dermatite Alérgica de Contato/tratamento farmacológico
14.
Angew Chem Int Ed Engl ; 63(1): e202314833, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37994382

RESUMO

N-, C-, O-, S-coordinated single-metal-sites (SMSs) have garnered significant attention due to the potential for significantly enhanced catalytic capabilities resulting from charge redistribution. However, significant challenges persist in the precise design of well-defined such SMSs, and the fundamental comprehension has long been impeded in case-by-case reports using carbon materials as investigation targets. In this work, the well-defined molecular catalysts with N3 C1 -anchored SMSs, i.e., N-confused metalloporphyrins (NCPor-Ms), are calculated for their catalytic oxygen reduction activity. Then, NCPor-Ms with corresponding N4 -anchored SMSs (metalloporphyrins, Por-Ms), are synthesized for catalytic activity evaluation. Among all, NCPor-Co reaches the top in established volcano plots. NCPor-Co also shows the highest half-wave potential of 0.83 V vs. RHE, which is much better than that of Por-Co (0.77 V vs. RHE). Electron-rich, low band gap and regulated d-band center contribute to the high activity of NCPor-Co. This study delves into the examination of well-defined asymmetric SMS molecular catalysts, encompassing both theoretical and experimental facets. It serves as a pioneering step towards enhancing the fundamental comprehension and facilitating the development of high-performance asymmetric SMS catalysts.

15.
J Am Chem Soc ; 145(44): 24126-24135, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37867298

RESUMO

Single-atom catalysts (SACs) have generated excitement for their potential to downsize metal particles to the atomic limit with engineerable local environments and improved catalytic reactivities and selectivities. However, successes have been limited to small-molecule transformations with little progress toward targeting complex-building reactions, such as metal-catalyzed cross-coupling. Using a supercritical carbon-dioxide-assisted protocol, we report a heterogeneous single-atom Pt-catalyzed Heck reaction, which provides the first C-C bond-forming migratory insertion on SACs. Our quantum mechanical computations establish the reaction mechanism to involve a novel C-rich coordination site (i.e., PtC4) that demonstrates an unexpected base effect. Notably, the base was found to transiently modulate the coordination environment to allow migratory insertion into an M-C species, a process with a high steric impediment with no previous example on SACs. The studies showcase how SACs can introduce coordination structures that have remained underexplored in catalyst design. These findings offer immense potential for transferring the vast and highly versatile reaction manifold of migratory-insertion-based bond-forming protocols to heterogeneous SACs.

16.
Scand J Immunol ; 98(2): e13275, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38441378

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic underlines a persistent threat of respiratory tract infectious diseases and warrants preparedness for a rapid response. At present, COVID-19 has had a serious social impact and imposed a heavy global burden on public health. The exact pathogenesis of COVID-19 has not been fully elucidated. Since the outbreak of COVID-19, a renewed attention has been brought to Toll-like receptors (TLRs). Available data and new findings have demonstrated that the interaction of human TLRs and SARS-CoV-2 is a vital mediator of COVID-19 immunopathogenesis. TLRs such as TLR2, 4, 7 and 8 are potentially important in viral combat and activation of immunity in patients with COVID-19. Therapeutics targeting TLRs are currently considered promising options against the pandemic. A number of TLR-targeting immunotherapeutics are now being investigated in preclinical studies and different phases of clinical trials. In addition, innovative vaccines based on TLRs under development could be a promising approach for building a new generation of vaccines to solve the current challenges. In this review, we summarize recent progress in the role of TLRs in COVID-19, focusing the new candidate drugs targeting TLRs, the current technology and potential paths forward for employing TLR agonists as vaccine adjuvants.


Assuntos
COVID-19 , Vacinas , Humanos , SARS-CoV-2 , Surtos de Doenças , Receptores Toll-Like
17.
Inorg Chem ; 62(13): 5262-5269, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36947415

RESUMO

Porous carbon-supported atomically ordered intermetallic compounds (IMCs) are promising electrocatalysts in boosting oxygen reduction reaction (ORR) for fuel cell applications. However, the formation mechanism of IMC structures under high temperatures is poorly understood, which hampers the synthesis of highly ordered IMC catalysts with promoted ORR performance. Here, we employ high-temperature X-ray diffraction and energy-dispersive spectroscopic elemental mapping techniques to study the formation process of IMCs, by taking PtCo for example, in an industry-relevant impregnation synthesis. We find that high-temperature annealing is crucial in promoting the formation of alloy particles with a stoichiometric Co/Pt ratio, which in turn is the precondition for transforming the disordered alloys to ordered intermetallic structures at a relatively low temperature. Based on the findings, we accordingly synthesize highly ordered L10-type PtCo catalysts with a remarkable ORR performance in fuel cells.

18.
Acta Pharmacol Sin ; 44(5): 954-968, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36460834

RESUMO

Chronic pain patients often have anxiety disorders, and some of them suffer from anxiety even after analgesic administration. In this study, we investigated the role of AMPAR-mediated synaptic transmission in the ventromedial prefrontal cortex (vmPFC) in chronic pain-induced persistent anxiety in mice and explored potential drug targets. Chronic inflammatory pain was induced in mice by bilateral injection of complete Freund's adjuvant (CFA) into the planta of the hind paws; anxiety-like behaviours were assessed with behavioural tests; S-nitrosylation and AMPAR-mediated synaptic transmission were examined using biochemical assays and electrophysiological recordings, respectively. We found that CFA induced persistent upregulation of AMPAR membrane expression and function in the vmPFC of anxious mice but not in the vmPFC of non-anxious mice. The anxious mice exhibited higher S-nitrosylation of stargazin (an AMPAR-interacting protein) in the vmPFC. Inhibition of S-nitrosylation by bilaterally infusing an exogenous stargazin (C302S) mutant into the vmPFC rescued the surface expression of GluA1 and AMPAR-mediated synaptic transmission as well as the anxiety-like behaviours in CFA-injected mice, even after ibuprofen treatment. Moreover, administration of ZL006, a small molecular inhibitor disrupting the interaction of nNOS and PSD-95 (20 mg·kg-1·d-1, for 5 days, i.p.), significantly reduced nitric oxide production and S-nitrosylation of AMPAR-interacting proteins in the vmPFC, resulting in anxiolytic-like effects in anxious mice after ibuprofen treatment. We conclude that S-nitrosylation is necessary for AMPAR trafficking and function in the vmPFC under chronic inflammatory pain-induced persistent anxiety conditions, and nNOS-PSD-95 inhibitors could be potential anxiolytics specific for chronic inflammatory pain-induced persistent anxiety after analgesic treatment.


Assuntos
Ansiedade , Dor Crônica , Córtex Pré-Frontal , Receptores de Glutamato , Animais , Camundongos , Ansiedade/etiologia , Ansiedade/metabolismo , Transtornos de Ansiedade , Dor Crônica/complicações , Dor Crônica/metabolismo , Ibuprofeno , Córtex Pré-Frontal/metabolismo , Transmissão Sináptica , Receptores de Glutamato/química , Receptores de Glutamato/metabolismo , Inflamação/complicações , Inflamação/metabolismo
19.
Int J Urol ; 30(12): 1122-1132, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37602677

RESUMO

OBJECTIVES: This study aims to reveal immunophenotypes associated with immunotherapy response in bladder cancer, identify the signature genes of immune subtypes, and provide new molecular targets for improving immunotherapy response. METHODS: Bladder cancer immunophenotypes were characterized in the bulk RNA sequencing dataset GSE32894 and Imvigor210, and gene expression signatures were established to identify the immunophenotypes. Expression of gene signatures were validated in single-cell RNA sequencing dataset GSE145140 and human proteins expression data source. Investigation of Immunotherapy Response was performed in IMvigor210 dataset. Prognosis of tumor immunophenotypes was further analyzed. RESULTS: Inflamed and immune-excluded immunophenotypes were characterized based on the tumor immune cell scores. Risk score models that were established rely on RNA sequencing profiles and overall survival of bladder cancer cohorts. The inflamed tumors had lower risk scores, and the low-risk tumors were more likely to respond to atezolizumab, receiving complete response/partial response (CR/PR). Patients who responded to atezolizumab had higher SRRM4 and lower NPHS1 and TMEM72 expression than the non-responders. SRRM4 expression was a protective factor for bladder cancer prognosis, while the NPHS1 and TMEM72 showed the opposite pattern. CONCLUSION: This study provided a novel classification method for tumor immunophenotypes. Bladder cancer immunophenotypes can predict the response to immune checkpoint blockade. The immunophenotypes can be identified by the expression of signature genes.


Assuntos
Síndrome Nefrótica , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , Imunoterapia , Microambiente Tumoral , Prognóstico , Proteínas do Tecido Nervoso
20.
J Plant Biol ; 66(3): 269-282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33424241

RESUMO

Although morphology and grain size are important to rice growth and yield, the identity of abundant natural allelic variations that determine agronomically important differences in crops is unknown. Here, we characterized the function of mitogen-activated protein kinase 3 from Oryza officinalis Wall. ex Watt encoded by OrMKK3. Different alternative splicing variants occurred in OrMKK3. Green fluorescent protein (GFP)-OrMKK3 fusion proteins localized to the cell membrane and nuclei of rice protoplasts. Overexpression of OrMKK3 influenced the expression levels of the grain size-related genes SMG1, GW8, GL3, GW2, and DEP3. Phylogenetic analysis showed that OrMKK3 is well conserved in plants while showing large amounts of variation between indica, japonica, and wild rice. In addition, OrMKK3 slightly influenced brassinosteroid (BR) responses and the expression levels of BR-related genes. Our findings thus identify a new gene, OrMKK3, influencing morphology and grain size and that represents a possible link between mitogen-activated protein kinase and BR response pathways in grain growth. Supplementary Information: The online version contains supplementary material available at 10.1007/s12374-020-09290-2.

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