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1.
Immunity ; 55(2): 237-253.e8, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35081371

RESUMO

The Th17 cell-lineage-defining cytokine IL-17A contributes to host defense and inflammatory disease by coordinating multicellular immune responses. The IL-17 receptor (IL-17RA) is expressed by diverse intestinal cell types, and therapies targeting IL-17A induce adverse intestinal events, suggesting additional tissue-specific functions. Here, we used multiple conditional deletion models to identify a role for IL-17A in secretory epithelial cell differentiation in the gut. Paneth, tuft, goblet, and enteroendocrine cell numbers were dependent on IL-17A-mediated induction of the transcription factor ATOH1 in Lgr5+ intestinal epithelial stem cells. Although dispensable at steady state, IL-17RA signaling in ATOH1+ cells was required to regenerate secretory cells following injury. Finally, IL-17A stimulation of human-derived intestinal organoids that were locked into a cystic immature state induced ATOH1 expression and rescued secretory cell differentiation. Our data suggest that the cross talk between immune cells and stem cells regulates secretory cell lineage commitment and the integrity of the mucosa.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Mucosa Intestinal/citologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Interleucina-17/metabolismo , Células-Tronco/metabolismo , Animais , Comunicação Celular , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Humanos , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Intestinos/patologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Receptores de Interleucina-17/deficiência , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Células-Tronco/citologia
2.
Nat Immunol ; 14(11): 1127-36, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24036998

RESUMO

Inflammation is a critical component of the immune response. However, acute or chronic inflammation can be highly destructive. Uncontrolled inflammation forms the basis for allergy, asthma and various autoimmune disorders. Here we identified a signaling pathway that was exclusively responsible for the production of inflammatory cytokines but not for cytotoxicity. Recognition of tumor cells expressing the NK cell-activatory ligands H60 or CD137L by mouse natural killer (NK) cells led to efficient cytotoxicity and the production of inflammatory cytokines. Both of those effector functions required the kinases Lck, Fyn and PI(3)K (subunits p85α and p110δ) and the signaling protein PLC-γ2. However, a complex of Fyn and the adaptor ADAP exclusively regulated the production of inflammatory cytokines but not cytotoxicity in NK cells. That unique function of ADAP required a Carma1-Bcl-10-MAP3K7 signaling axis. Our results have identified molecules that can be targeted to regulate inflammation without compromising NK cell cytotoxicity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Proteínas Adaptadoras de Sinalização CARD/imunologia , Citocinas/biossíntese , Células Matadoras Naturais/imunologia , MAP Quinase Quinase Quinases/imunologia , Proteínas Proto-Oncogênicas c-fyn/imunologia , Transdução de Sinais/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteína 10 de Linfoma CCL de Células B , Proteínas Adaptadoras de Sinalização CARD/genética , Linhagem Celular Tumoral , Técnicas de Cocultura , Citocinas/imunologia , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Inflamação , Células Matadoras Naturais/patologia , Linfoma/genética , Linfoma/imunologia , Linfoma/patologia , MAP Quinase Quinase Quinases/genética , Camundongos , Proteínas Proto-Oncogênicas c-fyn/genética
3.
Immunity ; 44(3): 659-671, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26982366

RESUMO

Interleukin-17 (IL-17) and IL-17 receptor (IL-17R) signaling are essential for regulating mucosal host defense against many invading pathogens. Commensal bacteria, especially segmented filamentous bacteria (SFB), are a crucial factor that drives T helper 17 (Th17) cell development in the gastrointestinal tract. In this study, we demonstrate that Th17 cells controlled SFB burden. Disruption of IL-17R signaling in the enteric epithelium resulted in SFB dysbiosis due to reduced expression of α-defensins, Pigr, and Nox1. When subjected to experimental autoimmune encephalomyelitis, IL-17R-signaling-deficient mice demonstrated earlier disease onset and worsened severity that was associated with increased intestinal Csf2 expression and elevated systemic GM-CSF cytokine concentrations. Conditional deletion of IL-17R in the enteric epithelium demonstrated that there was a reciprocal relationship between the gut microbiota and enteric IL-17R signaling that controlled dysbiosis, constrained Th17 cell development, and regulated the susceptibility to autoimmune inflammation.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Bactérias Gram-Positivas Formadoras de Endosporo/imunologia , Intestinos/fisiologia , Receptores de Interleucina-17/metabolismo , Células Th17/imunologia , Animais , Disbiose/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interações Hospedeiro-Patógeno , Imunidade nas Mucosas/genética , Interleucina-17/metabolismo , Intestinos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microbiota , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , NADPH Oxidase 1 , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Interleucina-17/genética , Transdução de Sinais/genética , Células Th17/microbiologia , alfa-Defensinas/genética , alfa-Defensinas/metabolismo
4.
Small ; 20(15): e2304574, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009795

RESUMO

Direct selective transformation of greenhouse methane (CH4) to liquid oxygenates (methanol) can substitute energy-intensive two-step (reforming/Fischer-Tropsch) synthesis while creating environmental benefits. The development of inexpensive, selective, and robust catalysts that enable room temperature conversion will decide the future of this technology. Single-atom catalysts (SACs) with isolated active centers embedded in support have displayed significant promises in catalysis to drive challenging reactions. Herein, high-density Ni single atoms are developed and stabilized on carbon nitride (NiCN) via thermal condensation of preorganized Ni-coordinated melem units. The physicochemical characterization of NiCN with various analytical techniques including HAADF-STEM and X-ray absorption fine structure (XAFS) validate the successful formation of Ni single atoms coordinated to the heptazine-constituted CN network. The presence of uniform catalytic sites improved visible absorption and carrier separation in densely populated NiCN SAC resulting in 100% selective photoconversion of (CH4) to methanol using H2O2 as an oxidant. The superior catalytic activity can be attributed to the generation of high oxidation (NiIII═O) sites and selective C─H bond cleavage to generate •CH3 radicals on Ni centers, which can combine with •OH radicals to generate CH3OH.

5.
J Exp Bot ; 75(1): 219-240, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37813680

RESUMO

Flavonols are structurally and functionally diverse biomolecules involved in plant biotic and abiotic stress tolerance, pollen development, and inhibition of auxin transport. However, their effects on global gene expression and signaling pathways are unclear. To explore the roles of flavonol metabolites in signaling, we performed comparative transcriptome and targeted metabolite profiling of seedlings from the flavonol-deficient Arabidopsis loss-of-function mutant flavonol synthase1 (fls1) with and without exogenous supplementation of flavonol derivatives (kaempferol, quercetin, and rutin). RNA-seq results indicated that flavonols modulate various biological and metabolic pathways, with significant alterations in camalexin and aliphatic glucosinolate synthesis. Flavonols negatively regulated camalexin biosynthesis but appeared to promote the accumulation of aliphatic glucosinolates via transcription factor-mediated up-regulation of biosynthesis genes. Interestingly, upstream amino acid biosynthesis genes involved in methionine and tryptophan synthesis were altered under flavonol deficiency and exogenous supplementation. Quercetin treatment significantly up-regulated aliphatic glucosinolate biosynthesis genes compared with kaempferol and rutin. In addition, expression and metabolite analysis of the transparent testa7 mutant, which lacks hydroxylated flavonol derivatives, clarified the role of quercetin in the glucosinolate biosynthesis pathway. This study elucidates the molecular mechanisms by which flavonols interfere with signaling pathways, their molecular targets, and the multiple biological activities of flavonols in plants.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Flavonóis/metabolismo , Glucosinolatos/metabolismo , Quempferóis/metabolismo , Quempferóis/farmacologia , Quercetina/metabolismo , Quercetina/farmacologia , Vias Biossintéticas , Rutina
6.
Chemistry ; : e202402026, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106258

RESUMO

Doping in semiconductor quantum dots (QDs) using optically active dopants tailors their optical, electronic, and magnetic properties beyond what is achieved by controlling size, shape, and composition. Herein, we synergistically modulated the optical properties of eco-friendly ZnInSe2/ZnSe core/shell QDs by incorporating Cu-doping and Mn-alloying into their core and shell to investigate their use in anti-counterfeiting and information encryption. The engineered "Cu:ZnInSe2/Mn:ZnSe" core/shell QDs exhibit an intense bright orange photoluminescence (PL) emission centered at 606 nm, with better color purity than the undoped and individually doped core/shell QDs. The average PL lifetime is significantly extended to 201 ns, making it relevant for complex encryption and anti-counterfeiting. PL studies reveal that in Cu:ZnInSe2/Mn:ZnSe, the photophysical emission arises from the Cu state via radiative transition from the Mn 4T1 state. Integration of Cu:ZnInSe2/Mn:ZnSe core/shell QDs into poly(methyl methacrylate) (PMMA) serves as versatile smart concealed luminescent inks for both writing and printing patterns. The features of these printed patterns using Cu:ZnInSe2/Mn:ZnSe core/shell QDs persisted after 10 weeks of water-soaking and retained 70 % of PL emission intensity at 170 °C, demonstrating excellent thermal stability. This work provides an efficient approach to enhance both the emission and the stability of eco-friendly QDs via dopant engineering for fluorescence anti-counterfeiting applications.

7.
Sex Transm Dis ; 51(2): 125-127, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37934152

RESUMO

ABSTRACT: 1 H-NMR metabolomics-derived biomarkers maltose, acetate, formate, and lactate have excellent potential as predictive biomarkers for bacterial vaginosis with an area under curve of 0.97 (95% confidence interval, 0.88-1.00), sensitivity of 0.90, and specificity of 0.95.


Assuntos
Vaginose Bacteriana , Feminino , Humanos , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/microbiologia , Metabolômica , Biomarcadores , Acetatos
8.
Langmuir ; 40(31): 16190-16207, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39049496

RESUMO

A numerical method is proposed to simulate the roughness scale interface dynamics of a slow-moving fluid interface as it advances over a chemically homogeneous rough surface. Analysis of the governing augmented Navier-Stokes and Young's boundary condition equations shows how the local interface behavior can be represented via a series of incrementally advanced equilibrium interfacial morphologies. Combined with a roughness scale mechanical energy balance [Harvie, D. J. E. Contact-angle hysteresis on rough surfaces: mechanical energy balance framework. J. Fluid Mech. 2024, 986, A17], the simulations are used to calculate the energy dissipation associated with a surface decorated with a periodic array of round-edge square pillars. This dissipation is used to predict static contact angle hysteresis (CAH) from knowledge of just the surface roughness topography and equilibrium contact angle. We show that the energy dissipated varies approximately as ϕln ϕ (with ϕ being the area fraction), becoming zero as ϕ → 0. The CAH predicted by our method is in good agreement with the experimental results of Forsberg et al. [Forsberg, P. S.; Priest, C.; Brinkmann, M.; Sedev, R.; Ralston, J. Contact line pinning on microstructured surfaces for liquids in the Wenzel state. Langmuir 2010, 26, 860-865], thereby demonstrating that our numerical method of simulating interfacial dynamics adequately captures the real interface motion, as well as illustrating how far-field contact angle and energy dissipation approaches are consistent for this surface. We also compute CAH for an interface moving at 45° to the surface periodicity direction to show that the experimental measurements are bracketed by the 0° and 45° advance direction results. The proposed method opens up the field to quantitative analysis, surface functionalization, and design for different specific applications.

9.
Langmuir ; 40(10): 5040-5059, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38419155

RESUMO

Polluted water has become a concern for the scientific community as it causes many severe threats to living beings. Detection or removal of contaminants present in wastewater and attaining purity of water that can be used for various purposes are a primary responsibility. Different treatment methods have already been used for the purification of sewage. There is a need for low-cost, highly selective, and reusable materials that can efficiently remove pollutants or purify contaminated water. In this regard, MOFs have shown significant potential for applications such as supercapacitors, drug delivery, gas storage, pollutant adsorption, etc. The outstanding structural diversity, substantial surface areas, and adjustable pore sizes of MOFs make them superior candidates for wastewater treatment. This Review provides an overview of the interaction science and engineering (kinetic and thermodynamic aspects with interactions) underpinning MOFs for water purification. First, fundamental strategies for the synthesis methods of MOFs, different categories, and their applicability in wastewater treatment are summarized, followed by a detailed explanation of various interaction mechanisms. Finally, current challenges and future outlooks for research on MOF materials toward the adsorption of hazardous components are discussed. A new avenue for modifying their structural characteristics for the adsorption and separation of hazardous materials, which will undoubtedly direct future work, is also summarized.

10.
Mol Divers ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083219

RESUMO

Helminthiasis, affecting billions globally, poses a significant health concern, especially in impoverished regions with inadequate sanitation. The intricate anatomical complexity of helminths requires specialized treatment approaches. There is currently no effective vaccine against helminth infections. Anthelmintics, crucial for combating these infections, target neuromuscular functions in parasites without harming the host. However, the emergence of resistance to existing anthelmintics, notably benzimidazoles, presents a growing global challenge. This review delves into the structure-activity relationship of previously synthesized core anthelmintic scaffolds-Benzimidazole, coumarin, pyrazoline, triazole, and others-to elucidate their promising anthelmintic activities. Understanding the structure-activity relationship of these novel benzimidazole derivatives, Coumarin derivatives, and others is crucial in designing potent anthelmintics, overcoming resistance, and optimizing efficacy to combat the escalating global burden of helminth infections. In the present review, we cover recently studied compounds (from the year 2019 to till date) which have promising anthelmintic activity. This review will be useful for the pharmacology and medicinal chemistry researchers working in the area anthelmintics with various scaffolds like aminobenzothiazole, benzimidazole, benzothiazole, coumarin, chromene, spiroketal, pyrazoline, triazole, etc. to design novel potent anthelmintic compound.

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