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1.
Nature ; 621(7977): 75-81, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37673990

RESUMO

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

2.
EMBO J ; 43(13): 2582-2605, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38806658

RESUMO

Necrosis in solid tumors is commonly associated with poor prognostic but how these lesions expand remains unclear. Studies have found that neutrophils associate with and contribute to necrosis development in glioblastoma by inducing tumor cell ferroptosis through transferring myeloperoxidase-containing granules. However, the mechanism of neutrophilic granule transfer remains elusive. We performed an unbiased small molecule screen and found that statins inhibit neutrophil-induced tumor cell death by blocking the neutrophilic granule transfer. Further, we identified a novel process wherein neutrophils are engulfed by tumor cells before releasing myeloperoxidase-containing contents into tumor cells. This neutrophil engulfment is initiated by integrin-mediated adhesion, and further mediated by LC3-associated phagocytosis (LAP), which can be blocked by inhibiting the Vps34-UVRAG-RUBCN-containing PI3K complex. Myeloperoxidase inhibition or Vps34 depletion resulted in reduced necrosis formation and prolonged mouse survival in an orthotopic glioblastoma mouse model. Thus, our study unveils a critical role for LAP-mediated neutrophil internalization in facilitating the transfer of neutrophilic granules, which in turn triggers tumor cell death and necrosis expansion. Targeting this process holds promise for improving glioblastoma prognosis.


Assuntos
Ferroptose , Glioblastoma , Neutrófilos , Fagocitose , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/imunologia , Glioblastoma/tratamento farmacológico , Animais , Neutrófilos/imunologia , Neutrófilos/metabolismo , Humanos , Camundongos , Ferroptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Necrose
3.
EMBO Rep ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39191946

RESUMO

Aberrant mitochondrial fission/fusion dynamics are frequently associated with pathologies, including cancer. We show that alternative splice variants of the fission protein Drp1 (DNM1L) contribute to the complexity of mitochondrial fission/fusion regulation in tumor cells. High tumor expression of the Drp1 alternative splice variant lacking exon 16 relative to other transcripts is associated with poor outcome in ovarian cancer patients. Lack of exon 16 results in Drp1 localization to microtubules and decreased association with mitochondrial fission sites, culminating in fused mitochondrial networks, enhanced respiration, changes in metabolism, and enhanced pro-tumorigenic phenotypes in vitro and in vivo. These effects are inhibited by siRNAs designed to specifically target the endogenously expressed transcript lacking exon 16. Moreover, lack of exon 16 abrogates mitochondrial fission in response to pro-apoptotic stimuli and leads to decreased sensitivity to chemotherapeutics. These data emphasize the pathophysiological importance of Drp1 alternative splicing, highlight the divergent functions and consequences of changing the relative expression of Drp1 splice variants in tumor cells, and strongly warrant consideration of alternative splicing in future studies focused on Drp1.

4.
Proc Natl Acad Sci U S A ; 119(37): e2121848119, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067324

RESUMO

Refractory carbides are attractive candidates for support materials in heterogeneous catalysis because of their high thermal, chemical, and mechanical stability. However, the industrial applications of refractory carbides, especially silicon carbide (SiC), are greatly hampered by their low surface area and harsh synthetic conditions, typically have a very limited surface area (<200 m2 g-1), and are prepared in a high-temperature environment (>1,400 °C) that lasts for several or even tens of hours. Based on Le Chatelier's principle, we theoretically proposed and experimentally verified that a low-pressure carbothermal reduction (CR) strategy was capable of synthesizing high-surface area SiC (569.9 m2 g-1) at a lower temperature and a faster rate (∼1,300 °C, 50 Pa, 30 s). Such high-surface area SiC possesses excellent thermal stability and antioxidant capacity since it maintained stability under a water-saturated airflow at 650 °C for 100 h. Furthermore, we demonstrated the feasibility of our strategy for scale-up production of high-surface area SiC (460.6 m2 g-1), with a yield larger than 12 g in one experiment, by virtue of an industrial viable vacuum sintering furnace. Importantly, our strategy is  also applicable to the rapid synthesis of refractory metal carbides (NbC, Mo2C, TaC, WC) and even their emerging high-entropy carbides (VNbMoTaWC5, TiVNbTaWC5). Therefore, our low-pressure CR method provides an alternative strategy, not merely limited to temperature and time items, to regulate the synthesis and facilitate the upcoming industrial applications of carbide-based advanced functional materials.

5.
J Am Chem Soc ; 146(7): 4557-4569, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38345667

RESUMO

Intelligent utilization of the anionic redox reaction (ARR) in Li-rich cathodes is an advanced strategy for the practical implementation of next-generation high-energy-density rechargeable batteries. However, due to the intrinsic complexity of ARR (e.g., nucleophilic attacks), the instability of the cathode-electrolyte interphase (CEI) on a Li-rich cathode presents more challenges than typical high-voltage cathodes. Here, we manipulate CEI interfacial engineering by introducing an all-fluorinated electrolyte and exploiting its interaction with the nucleophilic attack to construct a gradient CEI containing a pair of fluorinated layers on a Li-rich cathode, delivering enhanced interfacial stability. Negative/detrimental nucleophilic electrolyte decomposition has been efficiently evolved to further reinforce CEI fabrication, resulting in the construction of LiF-based indurated outer shield and fluorinated polymer-based flexible inner sheaths. Gradient interphase engineering dramatically improved the capacity retention of the Li-rich cathode from 43 to 71% after 800 cycles and achieved superior cycling stability in anode-free and pouch-type full cells (98.8% capacity retention, 220 cycles), respectively.

6.
Acc Chem Res ; 56(5): 573-591, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716326

RESUMO

ConspectusBenzo-fused skeletons are ubiquitous in agrochemicals, medicines, natural products, catalysts, and other organic function materials. The assembly of these skeletons in an efficient manner is an actively explored field in organic synthesis. Palladium/norbornene (Pd/NBE) cooperative catalysis is a powerful tool for the expeditious assembly of polysubstituted arenes through bis-functionalization of the ortho and ipso positions of aryl iodides in one operation. Owing to the efforts of Lautens, Catellani, and others, an array of Pd/NBE-promoted annulations for the syntheses of diversified benzo-fused rings have been developed. However, these methods have not been broadly applied in total synthesis yet.Our group is interested in efficient and practical total synthesis of biologically active molecules. In the past 7 years, we have been devoted to the development of new annulation strategies for the assembly of common benzo-fused skeletons through Pd/NBE-promoted reactions of aryl iodides with novel bifunctional reagents. In this Account, we summarize our laboratory's systematic efforts in this direction. First, readily available epoxides and aziridines were exploited as versatile bifunctional alkylating reagents, which enables quick assembly of a series of valuable benzo-fused heterocycles, including isochromans, dihydrobenzofurans, 1,3-cis-tetrahydroisoquinolines (THIQs), 1,3-trans-THIQs, etc. Second, a convergent access to 5-7-membered benzo-fused carbocycles (including indanes and tetrahydronaphthalenes) was developed by Pd/NBE-promoted annulation of aryl iodides with simple olefinic alcohol-containing alkylating reagents. Third, a Pd/NBE-promoted annulation between aryl iodides and cyclohexanone-containing amination reagents was developed for the construction of benzo-fused N-containing bridged scaffolds. Thus, we have established a practical and versatile toolbox for the quick assembly of diversified benzo-fused skeletons. These new annulation reactions are of high chemo-, regio-, and stereoselectivities with good step and atom economy. Moreover, they are able to rapidly increase molecular complexity from simple building blocks. Finally, their synthetic value has been demonstrated by immediate adoption in several efficient total syntheses of medicines and complex natural products. Compared to conventional synthetic logics, the Pd/NBE-promoted annulation toolbox allows the development of highly convergent strategies, which significantly improves the overall synthetic efficiency.We believe the results presented in this Account will have significant implications beyond our research. It can be envisaged that new Pd/NBE-promoted annulations as well as new applications in complex total synthesis will be revealed in the near future.

7.
FASEB J ; 37(12): e23307, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37983646

RESUMO

Glioblastoma is one of the deadliest malignancies facing modern oncology today. The ability of glioblastoma cells to diffusely spread into neighboring healthy brain makes complete surgical resection nearly impossible and contributes to the recurrent disease faced by most patients. Although research into the impact of iron on glioblastoma has addressed proliferation, there has been little investigation into how cellular iron impacts the ability of glioblastoma cells to migrate-a key question, especially in the context of the diffuse spread observed in these tumors. Herein, we show that increasing cellular iron content results in decreased migratory capacity of human glioblastoma cells. The decrease in migratory capacity was accompanied by a decrease in cellular polarization in the direction of movement. Expression of CDC42, a Rho GTPase that is essential for both cellular migration and establishment of polarity in the direction of cell movement, was reduced upon iron treatment. We then analyzed a single-cell RNA-seq dataset of human glioblastoma samples and found that cells at the tumor periphery had a gene signature that is consistent with having lower levels of cellular iron. Altogether, our results suggest that cellular iron content is impacting glioblastoma cell migratory capacity and that cells with higher iron levels exhibit reduced motility.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/metabolismo , Movimento Celular/genética , Encéfalo/metabolismo , Linhagem Celular Tumoral , Neoplasias Encefálicas/metabolismo , Proliferação de Células
8.
Environ Res ; 246: 118069, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38160966

RESUMO

Heavy metals and metalloids (HMMs) inhibit the biodegradation of organic pollutants. The degree of inhibition depends not only on the concentration and bioavailability of HMMs but also on additional factors, such as environmental variables (e.g., inorganic components, organic matter, pH, and redox potential), the nature of the metals, and microbial species. Based on the degradation pattern and metal concentrations causing half biodegradation rate reductions (RC50s), the inhibition of biodegradation was: Hg2+, As2O3 > Cu2+, Cd2+, Pb2+, Cr3+ > Ni2+, Co2+ > Mn2+, Zn2+ > Fe3+. Four patterns were observed: inhibition increases with increasing metal concentration; low concentrations stimulate, while high concentrations inhibit; high concentrations inhibit less; and mild inhibition remains constant. In addition, metal ion mixtures have more complex inhibitory effects on the degradation of organic pollutants, which may be greater than, similar to, or less than that of individual HMMs. Finally, the inhibitory mechanism of HMMs on biodegradation is reviewed. HMMs generally have little impact on the biodegradation pathway of organic pollutants for bacterial strains. However, when pollutants are biodegraded by the community, HMMs may activate microbial populations harbouring different transformation pathways. HMMs can affect the biodegradation efficiency of organic pollutants by changing the surface properties of microbes, interfering with degradative enzymes, and interacting with general metabolism.


Assuntos
Poluentes Ambientais , Mercúrio , Metaloides , Metais Pesados , Poluentes do Solo , Metais Pesados/análise , Biodegradação Ambiental , Poluentes do Solo/análise , Monitoramento Ambiental
9.
Clin Lab ; 70(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38868895

RESUMO

BACKGROUND: TSH and ACTH are crucial hormones for diagnosing thyroid and adrenal diseases, and incorrect test reports can cause significant harm to patients. METHODS: The TSH and ACTH levels on the testing system of our laboratory were measured using "sandwich" assays. The patient had heterophilic antibodies in their body, causing a false increase in TSH and ACTH levels. RESULTS: TSH on the Abbott platform was 59.7 µIU/mL and on the Roche platform it was 4.33 µIU/mL. After pretreatment with HBR it was 3.95 µIU/mL; ACTH on the SIEMENS platform was 263.5 pg/mL, on the Abbott platform it was 47.6 pg/mL. After pretreatment with HBR it was 36.5 pg/mL. CONCLUSIONS: The patient's serum contains heterophilic antibodies, which interfere with the TSH and ACTH tested by this method.


Assuntos
Hormônio Adrenocorticotrópico , Anticorpos Heterófilos , Tireotropina , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/imunologia , Anticorpos Heterófilos/sangue , Anticorpos Heterófilos/imunologia , Tireotropina/sangue , Tireotropina/imunologia
10.
Clin Lab ; 70(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39193970

RESUMO

BACKGROUND: The examination of anti-double stranded DNA (ds-DNA) IgG antibody is of great significance for the diagnosis, differential diagnosis, assessment of disease activity, and prognosis of disease recurrence in SLE. METHODS: We used a chemiluminescence method to detect ds-DNA IgG and found that the levels of ds-DNA IgG antibody in the patient's serum were significantly increased and the indirect immunofluorescence (IIF) test result was negative. Laboratory tests show that the patient's RF level far exceeds the upper limit of their reference range. RESULTS: RF 110.6 IU/mL, ds-DNA IgG 753 IU/mL; After PEG6000 treatment, the RF was 108.7 IU/mL, and then the ds-DNA IgG was measured at 23.5 IU/mL. CONCLUSIONS: The RF IgM subtype is the main cause of RF interference in IgG antibody detection, mainly due to the binding of the Fc region of RF to the Fab segment of IgG. Combining with capture antibodies and labeled antibodies leads to the formation of non-specific detection signals, or directly reacting with the detected substance, resulting in false positive test results.


Assuntos
Anticorpos Antinucleares , Imunoglobulina G , Fator Reumatoide , Humanos , Fator Reumatoide/sangue , Fator Reumatoide/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/sangue , Feminino , Reações Falso-Positivas , DNA/imunologia , Adulto , Medições Luminescentes/métodos , Masculino
11.
Clin Lab ; 70(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38868871

RESUMO

BACKGROUND: Heterophilic antibodies (HA) are one of the main substances that interfere with immunology, especially chemiluminescence immunoassay. Non-specific binding, labeling antibodies, bridging to capture antibodies, or labeling antigens can interfere with the detection process, leading to serious discrepancies between the measured results and clinical manifestations, and even delaying clinical diagnosis and treatment. METHODS: This paper is a case of epidemic hemorrhagic fever causing pseudo CEA elevation caused by heterophagy induced antibodies in the body. RESULTS: The patient's CEA detected on the ABBOTT detection platform was 51.1 ng/mL, and on the ROCHE detection platforms it was 4.66 ng/mL, and treated by PEG precipitation it was 45.2 ng/mL, after diluting the sample the CEA was 50.2 ng/mL, meanwhile the patient's platelets were 96 x 109/L and serum creatinine was 188.4 µmol/L, epidemic hemorrhagic fever IgM antibody was positive. CONCLUSIONS: When the test results do not match clinical symptoms, further confirmation is required through additional testing. Patients who use mouse monoclonal antibody preparations for diagnosis or treatment may have human anti-mouse antibodies in their serum, and the test results may falsely increase or decrease.


Assuntos
Antígeno Carcinoembrionário , Humanos , Anticorpos Heterófilos/sangue , Anticorpos Heterófilos/imunologia , Antígeno Carcinoembrionário/sangue , Imunoglobulina M/sangue , Feminino , Idoso
12.
Clin Lab ; 70(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39257108

RESUMO

BACKGROUND: There have been only few reports on Rhupus syndrome with severe visceral involvement. Moreover, there was little consensus regarding its treatment. Belimumab is one of the options for treating this disease. For patients with clinical symptoms and elevated levels of anti CCP antibodies and anti-double stranded DNA antibodies, and it suggests Rhupus syndrome. After effective treatment, the decrease in levels of anti CCP antibodies and anti-double stranded DNA (ds-DNA) antibodies can effectively delay the progression of the disease and protect target organs. METHODS: We used a chemiluminescence instrument, (Yahuilong; Shenzhen, China), to measure the changes in CCP and dsDNA before and after treatment. RESULTS: Prior to treatment, the patient presented with symptoms of rheumatoid arthritis and systemic lupus erythematosus. Her laboratory tests showed dsDNA (214 IU/mL) and CCP level of ˃ 3,000 U/mL. After treatment with belimumab, the clinical symptoms were significantly relieved, and the patient's CCP IgG level decreased to 263.5 U/mL. A blood test found that her anti-dsDNA was negative. CONCLUSIONS: CCP and dsDNA can serve as indicators for the diagnosis and treatment of Rhupus syndrome.


Assuntos
Anticorpos Antinucleares , Anticorpos Monoclonais Humanizados , DNA , Humanos , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , DNA/imunologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/sangue , Pessoa de Meia-Idade , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Artrite Reumatoide/sangue , Imunossupressores/uso terapêutico , Resultado do Tratamento , Autoanticorpos/sangue , Autoanticorpos/imunologia , Adulto , Biomarcadores/sangue
13.
Nano Lett ; 23(3): 863-871, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36651872

RESUMO

Heterostructures comprising lanthanide-doped upconversion nanoparticles (DUCNPs) and metal-organic frameworks (MOFs) are emerging as promising nanosystems for integrating medical diagnosis and treatment. Here, the DUCNP@Mn-MOF nanocarrier was developed, which showed good efficiency for loading and delivering a cytotoxic antitumor agent (3-F-10-OH-evodiamine, FOE). The combined advantages of the pH-responsive and peroxidase-like properties of Mn-MOF and the unique optical features of DUCNPs granted the DUCNP@Mn-MOF/FOE system synergistic chemodynamic and chemotherapeutic effects. The DUCNP@Mn-MOF nanocarrier effectively overcame the intrinsic limitations of FOE, such as its unfavorable physicochemical properties and limited in vivo potency. This complexed nanosystem was responsive to the tumor microenvironment and showed excellent tumor targeting capability. Thus, DUCNP@Mn-MOF/FOE exhibited highly selective and bioavailable drug delivery properties and is promising for cancer therapy. In a mouse breast cancer model, DUCNP@Mn-MOF/FOE inhibited tumor growth without significant toxicity. Therefore, the proposed nanosystem represents a promising theragnostic platform for multimodal combination diagnosis and therapy of tumors.


Assuntos
Antineoplásicos , Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Animais , Camundongos , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/química , Neoplasias/tratamento farmacológico , Nanopartículas/química , Microambiente Tumoral
14.
Angew Chem Int Ed Engl ; 63(6): e202316790, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38116869

RESUMO

Electrolyte engineering is a fascinating choice to improve the performance of Li-rich layered oxide cathodes (LRLO) for high-energy lithium-ion batteries. However, many existing electrolyte designs and adjustment principles tend to overlook the unique challenges posed by LRLO, particularly the nucleophilic attack. Here, we introduce an electrolyte modification by locally replacing carbonate solvents in traditional electrolytes with a fluoro-ether. By benefit of the decomposition of fluoro-ether under nucleophilic O-related attacks, which delivers an excellent passivation layer with LiF and polymers, possessing rigidity and flexibility on the LRLO surface. More importantly, the fluoro-ether acts as "sutures", ensuring the integrity and stability of both interfacial and bulk structures, which contributed to suppressing severe polarization and enhancing the cycling capacity retention from 39 % to 78 % after 300 cycles for the 4.8 V-class LRLO. This key electrolyte strategy with comprehensive analysis, provides new insights into addressing nucleophilic challenge for high-energy anionic redox related cathode systems.

15.
J Neurosci ; 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35672149

RESUMO

Brain enriched voltage-gated sodium channel (VGSC) Nav1.2 and Nav1.6 are critical for electrical signaling in the central nervous system. Previous studies have extensively characterized cell-type specific expression and electrophysiological properties of these two VGSCs and how their differences contribute to fine-tuning of neuronal excitability. However, due to lack of reliable labeling and imaging methods, the sub-cellular localization and dynamics of these homologous Nav1.2 and Nav1.6 channels remain understudied. To overcome this challenge, we combined genome editing, super-resolution and live-cell single molecule imaging to probe subcellular composition, relative abundances and trafficking dynamics of Nav1.2 and Nav1.6 in cultured mouse and rat neurons and in male and female mouse brain. We discovered a previously uncharacterized trafficking pathway that targets Nav1.2 to the distal axon of unmyelinated neurons. This pathway utilizes distinct signals residing in the intracellular loop 1 (ICL1) between transmembrane domain I and II to suppress the retention of Nav1.2 in the axon initial segment (AIS) and facilitate its membrane loading at the distal axon. As mouse pyramidal neurons undergo myelination, Nav1.2 is gradually excluded from the distal axon as Nav1.6 becomes the dominant VGSC in the axon initial segment and nodes of Ranvier. In addition, we revealed exquisite developmental regulation of Nav1.2 and Nav1.6 localizations in the axon initial segment and dendrites, clarifying the molecular identity of sodium channels in these subcellular compartments. Together, these results unveiled compartment-specific localizations and trafficking mechanisms for VGSCs, which could be regulated separately to modulate membrane excitability in the brain.SIGNIFICANCE STATEMENTDirect observation of endogenous voltage-gated sodium channels reveals a previously uncharacterized distal axon targeting mechanism and the molecular identity of sodium channels in distinct subcellular compartments.

16.
J Am Chem Soc ; 145(1): 322-333, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36542493

RESUMO

Alternative antibacterial therapies refractory to existing mechanisms of antibiotic resistance are urgently needed. One such attractive therapy is to inhibit bacterial adhesion and colonization. Ser O-heptosylation (Ser O-Hep) on autotransporters of Gram-negative bacteria is a novel glycosylation and has been proven to be essential for bacterial colonization. Herein, we chemically synthesized glycopeptides containing this atypical glycan structure and an absolute C6 configuration through the assembly of Ser O-Hep building blocks. Using glycopeptides as haptens, we generated first-in-class poly- and monoclonal antibodies, termed Anti-SerHep1a and Anti-SerHep1b, that stereoselectively recognize Ser O-heptosylation (d/l-glycero) with high specificity in vitro and in vivo. Importantly, these antibodies effectively blocked diffusely adhering Escherichia coli 2787 adhesion to HeLa cells and in mice in a dose- and Ser O-Hep-dependent manner. Together, these antibodies represent not only useful tools for the discovery of unknown serine O-heptosylated proteins bearing various C6 chiral centers but also a novel class of antiadhesion therapeutic agents for the treatment of bacterial infection.


Assuntos
Anticorpos Monoclonais , Polissacarídeos , Humanos , Animais , Camundongos , Células HeLa , Glicosilação , Polissacarídeos/química , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Escherichia coli , Glicopeptídeos/química
17.
J Am Chem Soc ; 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029335

RESUMO

Element doping/substitution has been recognized as an effective strategy to enhance the structural stability of layered cathodes. However, abundant substitution studies not only lack a clear identification of the substitution sites in the material lattice, but the rigid interpretation of the transition metal (TM)-O covalent theory is also not sufficiently convincing, resulting in the doping/substitution proposals being dragged into design blindness. In this work, taking Li1.2Ni0.2Mn0.6O2 as a prototype, the intense correlation between the "disordered degree" (Li/Ni mixing) and interface-structure stability (e.g., TM-O environment, slab/lattice, and Li+ reversibility) is revealed. Specifically, the degree of disorder induced by the Mg/Ti substitution extends in the opposite direction, conducive to sharp differences in the stability of TM-O, Li+ diffusion, and anion redox reversibility, delivering fairly distinct electrochemical performance. Based on the established paradigm of systematic characterization/analysis, the "degree of disorder" has been shown to be a powerful indicator of material modification by element substitution/doping.

18.
Br J Cancer ; 128(11): 2126-2139, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36977825

RESUMO

BACKGROUND: Enhancing the response rate of immunotherapy will aid in the success of cancer treatment. Here, we aimed to explore the combined effect of immunogenic radiotherapy with anti-PD-L1 treatment in immunotherapy-resistant HNSCC mouse models. METHODS: The SCC7 and 4MOSC2 cell lines were irradiated in vitro. SCC7-bearing mice were treated with hypofractionated or single-dose radiotherapy followed by anti-PD-L1 therapy. The myeloid-derived suppressive cells (MDSCs) were depleted using an anti-Gr-1 antibody. Human samples were collected to evaluate the immune cell populations and ICD markers. RESULTS: Irradiation increased the release of immunogenic cell death (ICD) markers (calreticulin, HMGB1 and ATP) in SCC7 and 4MOSC2 in a dose-dependent manner. The supernatant from irradiated cells upregulated the expression of PD-L1 in MDSCs. Mice treated with hypofractionated but not single-dose radiotherapy were resistant to tumour rechallenge by triggering ICD, when combined with anti-PD-L1 treatment. The therapeutic efficacy of combination treatment partially relies on MDSCs. The high expression of ICD markers was associated with activation of adaptive immune responses and a positive prognosis in HNSCC patients. CONCLUSION: These results present a translatable method to substantially improve the antitumor immune response by combining PD-L1 blockade with immunogenic hypofractionated radiotherapy in HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Inibidores de Checkpoint Imunológico , Células Supressoras Mieloides , Carcinoma de Células Escamosas de Cabeça e Pescoço , Animais , Humanos , Camundongos , Antígeno B7-H1/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Imunoterapia/métodos , Células Supressoras Mieloides/metabolismo , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico
19.
Clin Exp Immunol ; 214(1): 26-35, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37458218

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that can give rise to joint swelling and inflammation, potentially affecting the entire body, closely linked to the state of T cells. The T-cell activation Rho GTPase activating protein (TAGAP) is associated with many autoimmune diseases including RA and is directly linked to the differentiation of Th17 cells. The present study intends to investigate the influence of TAGAP on the RA progression and its mechanism to empower new treatments for RA. A collagen-induced-arthritis (CIA) rat model was constructed, as well as the extraction of CD4+ T cells. RT-qPCR, H&E staining and safranin O/fast green staining revealed that TAGAP interference reduced TAGAP production in the ankle joint of CIA rats, and joint inflammation and swelling were alleviated, which reveals that TAGAP interference reduces synovial inflammation and cartilage erosion in the rat ankle joint. Expression of inflammatory factors (TNF-α, IL-1ß, and IL-17) revealed that TAGAP interference suppressed the inflammatory response. Expression of pro-inflammatory cytokines, matrix-degrading enzymes, and anti-inflammatory cytokines at the mRNA level was detected by RT-qPCR and revealed that TAGAP interference contributed to the remission of RA. Mechanistically, TAGAP interference caused a significant decrease in the levels of RhoA and NLRP3. Assessment of Th17/Treg levels by flow cytometry revealed that TAGAP promotes Th17 cells differentiation and inhibits Treg cells differentiation in vitro and in vivo. In conclusion, TAGAP interference may decrease the differentiation of Th17 cells by suppressing the expression of RhoA and NLRP3 to slow down the RA progression.


Assuntos
Artrite Experimental , Artrite Reumatoide , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Células Th17 , Inflamação , Citocinas/metabolismo , Diferenciação Celular
20.
Exp Eye Res ; 235: 109640, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37673368

RESUMO

Cataract is the leading cause of blindness in the world, and there is a lack of effective treatment drugs. CircRNA plays an important part in a variety of diseases, however, the role of circRNA in cataracts remains largely unknown. In this study, we constructed a cataract model of rats and obtained the circRNAs related to cataracts by whole transcriptome sequencing and circRNA-mRNA co-expression network. To investigate the effect and mechanism of circRNA 06209 on cataracts, we performed several in vivo and in vitro experiments, including CCK8 assay, flow cytometry, dual luciferase reporter assay, RIP assay, actinomycin D assay, and Western blot analysis. We identify that a necroptosis-related circRNA, circRNA 06209, is down-regulated in cataracts. Vitro experiments showed that up-regulation of circRNA 06209 could promote cell proliferation and inhibit cell apoptosis. Vivo experiments revealed that circRNA 06209 overexpression could inhibit the development of cataracts. Mechanistically, circRNA 06209 acts as a miRNA sponge and competitively binds to miR-6848-5p to curb the inhibitory effect of miR-6848-5p on ALOX15, thereby affecting cell viability and apoptosis. This study found that circRNA 06209 plays a critical part in inhibiting cataracts through the miR-6848-5p/ALOX15 pathway, suggesting that circRNA 06209 may be a promising therapeutic target for cataracts.


Assuntos
Catarata , MicroRNAs , RNA Circular , Animais , Ratos , Apoptose , Catarata/genética , MicroRNAs/genética , RNA Circular/genética , Humanos , Ensaios Enzimáticos
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