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1.
Nat Immunol ; 22(7): 865-879, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34140678

RESUMO

Reduced infiltration of anti-tumor lymphocytes remains a major cause of tumor immune evasion and is correlated with poor cancer survival. Here, we found that upregulation of regulator of G protein signaling (RGS)1 in helper TH1 cells and cytotoxic T lymphocytes (CTLs) reduced their trafficking to and survival in tumors and was associated with shorter survival of patients with breast and lung cancer. RGS1 was upregulated by type II interferon (IFN)-signal transducer and activator of transcription (STAT)1 signaling and impaired trafficking of circulating T cells to tumors by inhibiting calcium influx and suppressing activation of the kinases ERK and AKT. RGS1 knockdown in adoptively transferred tumor-specific CTLs significantly increased their infiltration and survival in breast and lung tumor grafts and effectively inhibited tumor growth in vivo, which was further improved when combined with programmed death ligand (PD-L)1 checkpoint inhibition. Our findings reveal RGS1 is important for tumor immune evasion and suggest that targeting RGS1 may provide a new strategy for tumor immunotherapy.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Quimiotaxia de Leucócito , Linfócitos do Interstício Tumoral/metabolismo , Proteínas RGS/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Apoptose , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/imunologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Técnicas de Cocultura , Citotoxicidade Imunológica , Feminino , Humanos , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/transplante , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Microscopia de Vídeo , Proteínas RGS/genética , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/transplante , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Fatores de Tempo , Imagem com Lapso de Tempo , Células Tumorais Cultivadas , Evasão Tumoral
2.
Cell ; 172(4): 841-856.e16, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29395328

RESUMO

Carcinoma-associated fibroblasts (CAFs) are abundant and heterogeneous stromal cells in tumor microenvironment that are critically involved in cancer progression. Here, we demonstrate that two cell-surface molecules, CD10 and GPR77, specifically define a CAF subset correlated with chemoresistance and poor survival in multiple cohorts of breast and lung cancer patients. CD10+GPR77+ CAFs promote tumor formation and chemoresistance by providing a survival niche for cancer stem cells (CSCs). Mechanistically, CD10+GPR77+ CAFs are driven by persistent NF-κB activation via p65 phosphorylation and acetylation, which is maintained by complement signaling via GPR77, a C5a receptor. Furthermore, CD10+GPR77+ CAFs promote successful engraftment of patient-derived xenografts (PDXs), and targeting these CAFs with a neutralizing anti-GPR77 antibody abolishes tumor formation and restores tumor chemosensitivity. Our study reveals a functional CAF subset that can be defined and isolated by specific cell-surface markers and suggests that targeting the CD10+GPR77+ CAF subset could be an effective therapeutic strategy against CSC-driven solid tumors.


Assuntos
Transformação Celular Neoplásica/imunologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Fibroblastos/imunologia , Neoplasias/imunologia , Células-Tronco Neoplásicas/imunologia , Neprilisina/imunologia , Receptores de Quimiocinas/imunologia , Microambiente Tumoral/imunologia , Células A549 , Transformação Celular Neoplásica/patologia , Fibroblastos/patologia , Humanos , Células MCF-7 , Proteínas de Neoplasias/imunologia , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Receptor da Anafilatoxina C5a
3.
Nat Immunol ; 19(10): 1112-1125, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30224822

RESUMO

Activation-induced cell death (AICD) of T lymphocytes can be exploited by cancers to escape immunological destruction. We demonstrated that tumor-specific cytotoxic T lymphocytes (CTLs) and type 1 helper T (TH1) cells, rather than type 2 helper T cells and regulatory T cells, were sensitive to AICD in breast and lung cancer microenvironments. NKILA, an NF-κB-interacting long noncoding RNA (lncRNA), regulates T cell sensitivity to AICD by inhibiting NF-κB activity. Mechanistically, calcium influx in stimulated T cells via T cell-receptor signaling activates calmodulin, thereby removing deacetylase from the NKILA promoter and enhancing STAT1-mediated transcription. Administering CTLs with NKILA knockdown effectively inhibited growth of breast cancer patient-derived xenografts in mice by increasing CTL infiltration. Clinically, NKILA overexpression in tumor-specific CTLs and TH1 cells correlated with their apoptosis and shorter patient survival. Our findings underscore the importance of lncRNAs in determining tumor-mediated T cell AICD and suggest that engineering lncRNAs in adoptively transferred T cells might provide a novel antitumor immunotherapy.


Assuntos
Carcinoma/imunologia , RNA Longo não Codificante/imunologia , Linfócitos T Citotóxicos/imunologia , Células Th1/imunologia , Evasão Tumoral/genética , Animais , Apoptose/imunologia , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Carcinoma/genética , Carcinoma/patologia , Feminino , Xenoenxertos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , RNA Longo não Codificante/genética
4.
Nature ; 625(7995): 593-602, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093017

RESUMO

Emerging data have shown that previously defined noncoding genomes might encode peptides that bind human leukocyte antigen (HLA) as cryptic antigens to stimulate adaptive immunity1,2. However, the significance and mechanisms of action of cryptic antigens in anti-tumour immunity remain unclear. Here mass spectrometry of the HLA class I (HLA-I) peptidome coupled with ribosome sequencing of human breast cancer samples identified HLA-I-binding cryptic antigenic peptides that were noncanonically translated by a tumour-specific circular RNA (circRNA): circFAM53B. The cryptic peptides efficiently primed naive CD4+ and CD8+ T cells in an antigen-specific manner and induced anti-tumour immunity. Clinically, the expression of circFAM53B and its encoded peptides was associated with substantial infiltration of antigen-specific CD8+ T cells and better survival in patients with breast cancer and patients with melanoma. Mechanistically, circFAM53B-encoded peptides had strong binding affinity to both HLA-I and HLA-II molecules. In vivo, administration of vaccines consisting of tumour-specific circRNA or its encoded peptides in mice bearing breast cancer tumours or melanoma induced enhanced infiltration of tumour-antigen-specific cytotoxic T cells, which led to effective tumour control. Overall, our findings reveal that noncanonical translation of circRNAs can drive efficient anti-tumour immunity, which suggests that vaccination exploiting tumour-specific circRNAs may serve as an immunotherapeutic strategy against malignant tumours.


Assuntos
Neoplasias da Mama , Melanoma , Peptídeos , Biossíntese de Proteínas , RNA Circular , Animais , Feminino , Humanos , Camundongos , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Espectrometria de Massas , Melanoma/genética , Melanoma/imunologia , Melanoma/mortalidade , Melanoma/patologia , Peptídeos/genética , Peptídeos/imunologia , Perfil de Ribossomos , RNA Circular/genética , RNA Circular/metabolismo , Análise de Sobrevida
5.
Nature ; 583(7814): 133-138, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32528174

RESUMO

Neutrophil extracellular traps (NETs), which consist of chromatin DNA filaments coated with granule proteins, are released by neutrophils to trap microorganisms1-3. Recent studies have suggested that the DNA component of NETs (NET-DNA) is associated with cancer metastasis in mouse models4-6. However, the functional role and clinical importance of NET-DNA in metastasis in patients with cancer remain unclear. Here we show that NETs are abundant in the liver metastases of patients with breast and colon cancers, and that serum NETs can predict the occurrence of liver metastases in patients with early-stage breast cancer. NET-DNA acts as a chemotactic factor to attract cancer cells, rather than merely acting as a 'trap' for them; in several mouse models, NETs in the liver or lungs were found to attract cancer cells to form distant metastases. We identify the transmembrane protein CCDC25 as a NET-DNA receptor on cancer cells that senses extracellular DNA and subsequently activates the ILK-ß-parvin pathway to enhance cell motility. NET-mediated metastasis is abrogated in CCDC25-knockout cells. Clinically, we show that the expression of CCDC25 on primary cancer cells is closely associated with a poor prognosis for patients. Overall, we describe a transmembrane DNA receptor that mediates NET-dependent metastasis, and suggest that targeting CCDC25 could be an appealing therapeutic strategy for the prevention of cancer metastasis.


Assuntos
Neoplasias da Mama/patologia , DNA/metabolismo , Armadilhas Extracelulares/genética , Proteínas de Membrana/metabolismo , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Neutrófilos/metabolismo , Actinina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Proteínas de Membrana/genética , Camundongos , Prognóstico , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
6.
Genome Res ; 32(3): 437-448, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35105669

RESUMO

Dual-function regulatory elements (REs), acting as enhancers in some cellular contexts and as silencers in others, have been reported to facilitate the precise gene regulatory response to developmental signals in Drosophila melanogaster However, with few isolated examples detected, dual-function REs in mammals have yet to be systematically studied. We herein investigated this class of REs in the human genome and profiled their activity across multiple cell types. Focusing on enhancer-silencer transitions specific to the development of T cells, we built an accurate deep learning classifier of REs and identified about 12,000 silencers active in primary peripheral blood T cells that act as enhancers in embryonic stem cells. Compared with regular silencers, these dual-function REs are evolving under stronger purifying selection and are enriched for mutations associated with disease phenotypes and altered gene expression. In addition, they are enriched in the loci of transcriptional regulators, such as transcription factors (TFs) and chromatin remodeling genes. Dual-function REs consist of two intertwined but largely distinct sets of binding sites bound by either activating or repressing TFs, depending on the type of RE function in a given cell line. This indicates the recruitment of different TFs for different regulatory modes and a complex DNA sequence composition of these REs with dual activating and repressive encoding. With an estimated >6% of cell type-specific human silencers acting as dual-function REs, this overlooked class of REs requires a specific investigation on how their inherent functional plasticity might be a contributing factor to human diseases.


Assuntos
Elementos Facilitadores Genéticos , Genoma Humano , Animais , Drosophila melanogaster/genética , Regulação da Expressão Gênica , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Trends Immunol ; 43(7): 523-545, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35624021

RESUMO

Immune checkpoint blockade (ICB) therapies have achieved clinical benefit, but most 'immune-cold' solid tumors are not responsive. The diversity of immune evasion mechanisms remains a key obstacle in turning nonresponsive 'cold' tumors into responsive 'hot' ones. Therefore, exploring the mechanisms of such transitions and tumor immunotyping can provide significant insights into designing effective therapeutic strategies against cancer. Here, we focus on the latest advances regarding local and systemic regulatory mechanisms of immune responses in cold and hot tumors. We also highlight the necessity for tumor immunotyping through the assessment of multiple immunological variables using various diagnostic techniques and biomarkers. Finally, we discuss the challenges and potential clinical applications of immunophenotyping to turn cold tumors hot, which may further guide combined immunotherapies.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Imunidade , Imunoterapia/métodos , Neoplasias/tratamento farmacológico
8.
Nature ; 572(7770): 497-501, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31367036

RESUMO

Layered antiferromagnetism is the spatial arrangement of ferromagnetic layers with antiferromagnetic interlayer coupling. The van der Waals magnet chromium triiodide (CrI3) has been shown to be a layered antiferromagnetic insulator in its few-layer form1, opening up opportunities for various functionalities2-7 in electronic and optical devices. Here we report an emergent nonreciprocal second-order nonlinear optical effect in bilayer CrI3. The observed second-harmonic generation (SHG; a nonlinear optical process that converts two photons of the same frequency into one photon of twice the fundamental frequency) is several orders of magnitude larger than known magnetization-induced SHG8-11 and comparable to the SHG of the best (in terms of nonlinear susceptibility) two-dimensional nonlinear optical materials studied so far12,13 (for example, molybdenum disulfide). We show that although the parent lattice of bilayer CrI3 is centrosymmetric, and thus does not contribute to the SHG signal, the observed giant nonreciprocal SHG originates only from the layered antiferromagnetic order, which breaks both the spatial-inversion symmetry and the time-reversal symmetry. Furthermore, polarization-resolved measurements reveal underlying C2h crystallographic symmetry-and thus monoclinic stacking order-in bilayer CrI3, providing key structural information for the microscopic origin of layered antiferromagnetism14-18. Our results indicate that SHG is a highly sensitive probe of subtle magnetic orders and open up possibilities for the use of two-dimensional magnets in nonlinear and nonreciprocal optical devices.

9.
Small ; 20(24): e2307345, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38279570

RESUMO

The emergent electronic, spin, and other quantum properties of 2D heterostructures of graphene and transition metal dichalcogenides are controlled by the underlying interlayer coupling and associated charge and energy transfer dynamics. However, these processes are sensitive to interlayer distance and crystallographic orientation, which are in turn affected by defects, grain boundaries, or other nanoscale heterogeneities. This obfuscates the distinction between interlayer charge and energy transfer. Here, nanoscale imaging in coherent four-wave mixing (FWM) and incoherent two-photon photoluminescence (2PPL) is combined with a tip distance-dependent coupled rate equation model to resolve the underlying intra- and inter-layer dynamics while avoiding the influence of structural heterogeneities in mono- to multi-layer graphene/WSe2 heterostructures. With selective insertion of hBN spacer layers, it is shown that energy, as opposed to charge transfer, dominates the interlayer-coupled optical response. From the distinct nano-FWM and -2PPL tip-sample distance-dependent modification of interlayer and intralayer relaxation by tip-induced enhancement and quenching, an interlayer energy transfer time of τ ET ≈ ( 0 . 35 - 0.15 + 0.65 ) $\tau _{\rm ET} \approx (0.35^{+0.65}_{-0.15})$  ps consistent with recent reports is derived. As a local probe technique, this approach highlights the ability to determine intrinsic sample properties even in the presence of large sample heterogeneity.

10.
Planta ; 260(1): 26, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861179

RESUMO

MAIN CONCLUSION: CaTPS2 and CaTPS3 were significantly expressed in flowers of Curcuma alismatifolia 'Shadow' and demonstrated bifunctional enzyme activity, CaTPS2 generated linalool and nerolidol as products, and CaTPS3 catalyzed ß-myrcene and ß-farnesene formation. This study presents the discovery and functional characterization of floral terpene synthase (TPS) genes in Curcuma alismatifolia 'Shadow', a cultivar renowned for its unique fragrance. Addressing the gap in understanding the genetic basis of floral scent in this species, we identified eight TPS genes through comprehensive transcriptome sequencing. Among these, CaTPS2 and CaTPS3 were significantly expressed in floral tissues and demonstrated bifunctional enzyme activity corresponding to the major volatile compounds detected in 'Shadow'. Functional analyses, including in vitro assays complemented with rigorous controls and alternative identification methods, elucidated the roles of these TPS genes in terpenoid biosynthesis. In vitro studies were conducted via heterologous expression in E. coli, followed by purification of the recombinant protein using affinity chromatography, enzyme assays were performed with GPP/FPP as the substrate, and volatile products were inserted into the GC-MS for analysis. Partially purified recombinant protein of CaTPS2 catalyzed GPP and FPP to produce linalool and nerolidol, respectively, while partially purified recombinant protein of CaTPS3 generated ß-myrcene and ß-farnesene with GPP and FPP as substrates, respectively. Real-time quantitative PCR further validated the expression patterns of these genes, correlating with terpenoid accumulation in different plant tissues. Our findings illuminate the molecular mechanisms underpinning floral fragrance in C. alismatifolia and provide a foundation for future genetic enhancements of floral scent in ornamental plants. This study, therefore, contributes to the broader understanding of terpenoid biosynthesis in plant fragrances, paving the way for biotechnological applications in horticulture plant breeding.


Assuntos
Monoterpenos Acíclicos , Alquil e Aril Transferases , Curcuma , Flores , Sesquiterpenos , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Flores/genética , Flores/enzimologia , Flores/metabolismo , Sesquiterpenos/metabolismo , Monoterpenos Acíclicos/metabolismo , Curcuma/genética , Curcuma/enzimologia , Curcuma/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Terpenos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Filogenia , Odorantes
11.
Opt Lett ; 49(14): 3990-3993, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008759

RESUMO

Atomically thin transition metal dichalcogenides (TMDS) offer a promising route to the scaling down of optoelectronic devices to the ultimate thickness limit. But the weak light-matter interaction caused by their atomically thin nature makes them inevitably rely on external photonic structures to enhance optical absorption. Here, we report chiral absorption enhancement in atomically thin tungsten diselenide (WSe2) using chiral resonances in photonic crystal (PhC) nanostructures patterned directly in WSe2 itself. We show that the quality factors (Q factors) of the resonances grow exponentially as the PhC thickness approaches atomic limit. As such, the strong interaction of high Q factor photonic resonance with the coexisting exciton resonance in WSe2 results into self-coupled exciton-polaritons. By balancing the light coupling and absorption rates, the incident light can critically couple to chiral resonances in WSe2 PhC exciton-polaritons, leading to the theoretically limited 50% optical absorptance with over 84% circular dichroism (CD).

12.
Phys Rev Lett ; 132(15): 152502, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682998

RESUMO

^{134}Xe is a candidate isotope for neutrinoless double beta decay (0νßß) search. In addition, the two-neutrino case (2νßß) allowed by the standard model of particle physics has not yet been observed. With the 656-kg natural xenon in the fiducial volume of the PandaX-4T detector, which contains 10.4% of ^{134}Xe, and its initial 94.9-day exposure, we have established the most stringent constraints on 2νßß and 0νßß of ^{134}Xe half-lives, with limits of 2.8×10^{22} yr and 3.0×10^{23} yr at 90% confidence level, respectively. The 2νßß (0νßß) limit surpasses the previously reported best result by a factor of 32 (2.7), highlighting the potential of large monolithic natural xenon detectors for double beta decay searches.

13.
Cell Commun Signal ; 22(1): 69, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273292

RESUMO

Tumors of the digestive system pose a significant threat to human health and longevity. These tumors are associated with high morbidity and mortality rates, leading to a heavy economic burden on healthcare systems. Several intratumoral microorganisms are present in digestive system tumors, and their sources and abundance display significant heterogeneity depending on the specific tumor subtype. These microbes have a complex and precise function in the neoplasm. They can facilitate tumor growth through various mechanisms, such as inducing DNA damage, influencing the antitumor immune response, and promoting the degradation of chemotherapy drugs. Therefore, these microorganisms can be targeted to inhibit tumor progression for improving overall patient prognosis. This review focuses on the current research progress on microorganisms present in the digestive system tumors and how they influence the initiation, progression, and prognosis of tumors. Furthermore, the primary sources and constituents of tumor microbiome are delineated. Finally, we summarize the application potential of intratumoral microbes in the diagnosis, treatment, and prognosis prediction of digestive system tumors. Video Abstract.


Assuntos
Neoplasias do Sistema Digestório , Humanos , Neoplasias do Sistema Digestório/diagnóstico , Neoplasias do Sistema Digestório/genética , Neoplasias do Sistema Digestório/patologia , Dano ao DNA
14.
Langmuir ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982808

RESUMO

Natural mineral-based advanced oxidation processes (AOPs) are now receiving increasing attention for the efficient degradation of pollutants. In this work, we used a common reducing agent (NaBH4) to treat natural Hematite to obtain modified Hematite (Hematite-(R)) and applied it to activate peracetic acid (PAA) for efficient degradation of cefazolin (CFZ). Compared with Hematite, the Hematite-(R)/PAA system increased the degradation rate of CFZ by 21.7% within 80 min under neutral conditions. Scavenging experiments and electron paramagnetic resonance (EPR) technology were introduced to identify the principal roles of 1O2, CH3C(O)OO•, and •OH for CFZ removal over the Hematite-(R)/PAA process. The outstanding capability of Hematite-(R) could be mainly due to the higher percentage of Fe(II) (52%) on the surface of catalysts. Furthermore, the possible degradation pathways of CFZ were explored. Moreover, the Hematite-(R)/PAA process showed a superior CFZ removal efficiency with a wide initial pH scope of 1.0-9.0. The degradation efficiency of CFZ showed a negligible effect in the presence of Cl-, SO42-, and NO3-, while significant inhibition was recorded after the addition of H2PO4- and CO32-. The inhibition of humic acid (HA) on CFZ degradation via the Hematite-(R)/PAA process showed an obvious concentration dependence. This work could provide strong support for the use of natural Hematite in water purification.

15.
Infection ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647828

RESUMO

BACKGROUND: Sepsis is a recognized global health challenge that places a considerable disease burden on countries. Although there has been some progress in the study of sepsis, the mortality rate of sepsis remains high. The relationship between serum osmolality and the prognosis of patients with sepsis is unclear. METHOD: Patients with sepsis who met the criteria in the Medical Information Mart for Intensive Care IV database were included in the study. Hazard ratios (HRs) and 95% confidence intervals (CIs) were determined using multivariable Cox regression. The relationship between serum osmolality and the 28-day mortality risk in patients with sepsis was investigated using curve fitting, and inflection points were calculated. RESULTS: A total of 13,219 patients with sepsis were enrolled in the study; the mean age was 65.1 years, 56.9 % were male, and the 28-day mortality rate was 18.8 %. After adjusting for covariates, the risk of 28-day mortality was elevated by 99% (HR 1.99, 95%CI 1.74-2.28) in the highest quintile of serum osmolality (Q5 >303.21) and by 59% (HR 1.59, 95%CI 1.39-1.83) in the lowest quintile (Q1 ≤285.80), as compared to the reference quintile (Q3 291.38-296.29). The results of the curve fitting showed a U-shaped relationship between serum osmolality and the risk of 28-day mortality, with an inflection point of 286.9 mmol/L. CONCLUSION: There is a U-shaped relationship between serum osmolality and the 28-day mortality risk in patients with sepsis. Higher or lower serum osmolality is associated with an increased risk of mortality in patients with sepsis. Patients with sepsis have a lower risk of mortality when their osmolality is 285.80-296.29 mmol/L.

16.
Environ Sci Technol ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319710

RESUMO

The NO3•-driven nighttime aging of brown carbon (BrC) is known to greatly impact its atmospheric radiative forcing. However, the impact of oxidation by NO3• on the optical properties of BrC in atmospheric waters as well as the associated reaction mechanism remain unclear. In this work, we found that the optical variation of BrC proxies under environmentally relevant NO3• exposure depends strongly on their sources, with enhanced light absorptivity for biomass-burning BrC but bleaching for urban aerosols and humic substances. High-resolution mass spectrometry using FT-ICR MS shows that oxidation by NO3• leads to the formation of light-absorbing species (e.g., nitrated organics) for biomass-burning BrC while destroying electron donors (e.g., phenols) within charge transfer complexes in urban aerosols and humic substances, as evidenced by transient absorption spectroscopy and NaBH4 reduction experiments as well. Moreover, we found that the measured rate constants between NO3• with real BrCs (k = (1.8 ± 0.6) × 107 MC-1s-1, expressed as moles of carbon) are much higher than those of individual model organic carbon (OC), suggesting the reaction with OCs may be a previously ill-quantified important sink of NO3• in atmospheric waters. This work provides insights into the kinetics and molecular transformation of BrC during the oxidation by NO3•, facilitating further evaluation of BrC's climatic effects and atmospheric NO3• levels.

17.
Environ Sci Technol ; 58(26): 11578-11586, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38899536

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are the primary organic carbons in soot. In addition to PAHs with even carbon numbers (PAHeven), substantial odd-carbon PAHs (PAHodd) have been widely observed in soot and ambient particles. Analyzing and understanding the photoaging of these compounds are essential for assessing their environmental effects. Here, using laser desorption ionization mass spectrometry (LDI-MS), we reveal the substantially different photoreactivity of PAHodd from PAHeven in the aging process and their MS detection through their distinct behaviors in the presence and absence of elemental carbon (EC) in soot. During direct photooxidation of organic carbon (OC) alone, the PAHeven are oxidized more rapidly than the PAHodd. However, the degradation of PAHodd becomes preponderant over PAHeven in the presence of EC during photoaging of the whole soot. All of these observations are proposed to originate from the more rapid hydrogen abstraction reaction from PAHodd in the EC-photosensitized reaction, owing to its unique structure of a single sp3-hybridized carbon site. Our findings reveal the photoreactivity and reaction mechanism of PAHodd for the first time, providing a comprehensive understanding of the oxidation of PAHs at a molecular level during soot aging and highlight the enhanced effect of EC on PAHodd ionization in LDI-MS analysis.


Assuntos
Carbono , Hidrocarbonetos Policíclicos Aromáticos , Fuligem , Hidrocarbonetos Policíclicos Aromáticos/química , Carbono/química , Fuligem/química , Processos Fotoquímicos , Oxirredução , Fotoquímica
18.
Anal Bioanal Chem ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953919

RESUMO

A candidate reference measurement procedure (RMP) for serum theophylline via isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. With a single-step precipitation pretreatment and a 6-min gradient elution, the method achieved baseline separation of theophylline and its analogs on a C18-packed column. A bracketing calibration method was used to ensure repeatable signal intensity and high measurement precision. The intra-assay and inter-assay imprecisions were 1.06%, 0.84%, 0.72% and 0.47%, 0.41%, 0.25% at concentrations of 4.22 µg/mL (23.40 µmol/L), 8.45 µg/mL (46.90 µmol/L), and 15.21 µg/mL (84.43 µmol/L), respectively. Recoveries ranged from 99.35 to 102.34%. The limit of detection (LoD) was 2 ng/mL, and the lowest limit of quantification (LLoQ) was 5 ng/mL. The linearity range extended from 0.47 to 60 µg/mL (2.61-333.04 µmol/L). No ion suppression and carry-over (< 0.68%) were observed. The relative bias for this candidate RMP that participated in 2023 External Quality Control for Reference Laboratories (RELA) conducted by the International Federation of Clinical Chemistry (IFCC) was within a range of 0.17 to 0.93%. Furthermore, two clinical immunoassay systems were compared with this candidate RMP, demonstrating good correlations. The results of the Trueness Verification Plan indicate significant differences among routine systems, highlighting the need for standardization efforts. The developed candidate RMP for serum theophylline serves as a precise reference baseline for standardizing clinical systems and assigning values to reference materials.

19.
Brain ; 146(4): 1403-1419, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36152315

RESUMO

Genome-wide association studies have identified 10q24.32 as a robust schizophrenia risk locus. Here we identify a regulatory variant (rs10786700) that disrupts binding of transcription factors at 10q24.32. We independently confirmed the association between rs10786700 and schizophrenia in a large Chinese cohort (n = 11 547) and uncovered the biological mechanism underlying this association. We found that rs10786700 resides in a super-enhancer element that exhibits dynamic activity change during the development process and that the risk allele (C) of rs10786700 conferred significant lower enhancer activity through enhancing binding affinity to repressor element-1 silencing transcription factor (REST). CRISPR-Cas9-mediated genome editing identified SUFU as a potential target gene by which rs10786700 might exert its risk effect on schizophrenia, as deletion of rs10786700 downregulated SUFU expression. We further investigated the role of Sufu in neurodevelopment and found that Sufu knockdown inhibited proliferation of neural stem cells and neurogenesis, affected molecular pathways (including neurodevelopment-related pathways, PI3K-Akt and ECM-receptor interaction signalling pathways) associated with schizophrenia and altered the density of dendritic spines. These results reveal that the functional risk single nucleotide polymorphism rs10786700 at 10q24.32 interacts with REST synergistically to regulate expression of SUFU, a novel schizophrenia risk gene which is involved in schizophrenia pathogenesis by affecting neurodevelopment and spine morphogenesis.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Fosfatidilinositol 3-Quinases/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética
20.
Cell Mol Life Sci ; 80(10): 287, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689602

RESUMO

Voltage-gated sodium (NaV) channels are transmembrane proteins that play a critical role in electrical signaling in the nervous system and other excitable tissues. µ-Conotoxins are peptide toxins from the venoms of marine cone snails (genus Conus) that block NaV channels with nanomolar potency. Most species of the subgenera Textilia and Afonsoconus are difficult to acquire; therefore, their venoms have yet to be comprehensively interrogated for µ-conotoxins. The goal of this study was to find new µ-conotoxins from species of the subgenera Textilia and Afonsoconus and investigate their selectivity at human NaV channels. Using RNA-seq of the venom gland of Conus (Textilia) bullatus, we identified 12 µ-conotoxin (or µ-conotoxin-like) sequences. Based on these sequences we designed primers which we used to identify additional µ-conotoxin sequences from DNA extracted from historical specimens of species from Textilia and Afonsoconus. We synthesized six of these µ-conotoxins and tested their activity on human NaV1.1-NaV1.8. Five of the six synthetic peptides were potent blockers of human NaV channels. Of these, two peptides (BuIIIB and BuIIIE) were potent blockers of hNaV1.3. Three of the peptides (BuIIIB, BuIIIE and AdIIIA) had submicromolar activity at hNaV1.7. This study serves as an example of the identification of new peptide toxins from historical DNA and provides new insights into structure-activity relationships of µ-conotoxins with activity at hNaV1.3 and hNaV1.7.


Assuntos
Conotoxinas , Caramujo Conus , Toxinas Biológicas , Humanos , Animais , Conotoxinas/farmacologia , Proteínas de Membrana , Canais de Sódio/genética
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