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1.
Cell ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971151

RESUMO

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Nat Immunol ; 25(4): 659-670, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499799

RESUMO

Combination therapy is a promising therapeutic strategy to enhance the efficacy of immune checkpoint blockade (ICB); however, predicting drugs for effective combination is challenging. Here we developed a general data-driven method called CM-Drug for screening compounds that can boost ICB treatment efficacy based on core and minor gene sets identified between responsive and nonresponsive samples in ICB therapy. The CM-Drug method was validated using melanoma and lung cancer mouse models, with combined therapeutic efficacy demonstrated in eight of nine predicted compounds. Among these compounds, taltirelin had the strongest synergistic effect. Mechanistic analysis and experimental verification demonstrated that taltirelin can stimulate CD8+ T cells and is mediated by the induction of thyroid-stimulating hormone. This study provides an effective and general method for predicting and evaluating drugs for combination therapy and identifies candidate compounds for future ICB combination therapy.


Assuntos
Neoplasias Pulmonares , Melanoma , Animais , Camundongos , Linfócitos T CD8-Positivos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Neoplasias Pulmonares/tratamento farmacológico
3.
Immunity ; 57(4): 876-889.e11, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38479384

RESUMO

Concentrations of the secondary bile acid, deoxycholic acid (DCA), are aberrantly elevated in colorectal cancer (CRC) patients, but the consequences remain poorly understood. Here, we screened a library of gut microbiota-derived metabolites and identified DCA as a negative regulator for CD8+ T cell effector function. Mechanistically, DCA suppressed CD8+ T cell responses by targeting plasma membrane Ca2+ ATPase (PMCA) to inhibit Ca2+-nuclear factor of activated T cells (NFAT)2 signaling. In CRC patients, CD8+ T cell effector function negatively correlated with both DCA concentration and expression of a bacterial DCA biosynthetic gene. Bacteria harboring DCA biosynthetic genes suppressed CD8+ T cells effector function and promoted tumor growth in mice. This effect was abolished by disrupting bile acid metabolism via bile acid chelation, genetic ablation of bacterial DCA biosynthetic pathway, or specific bacteriophage. Our study demonstrated causation between microbial DCA metabolism and anti-tumor CD8+ T cell response in CRC, suggesting potential directions for anti-tumor therapy.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Ácidos e Sais Biliares , Ácido Desoxicólico/farmacologia , Linfócitos T CD8-Positivos
4.
Immunity ; 47(2): 284-297.e5, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28813659

RESUMO

Ten-Eleven-Translocation-2 (Tet2) is a DNA methylcytosine dioxygenase that functions as a tumor suppressor in hematopoietic malignancies. We examined the role of Tet2 in tumor-tissue myeloid cells and found that Tet2 sustains the immunosuppressive function of these cells. We found that Tet2 expression is increased in intratumoral myeloid cells both in mouse models of melanoma and in melanoma patients and that this increased expression is dependent on an IL-1R-MyD88 pathway. Ablation of Tet2 in myeloid cells suppressed melanoma growth in vivo and shifted the immunosuppressive gene expression program in tumor-associated macrophages to a proinflammatory one, with a concomitant reduction of the immunosuppressive function. This resulted in increased numbers of effector T cells in the tumor, and T cell depletion abolished the reduced tumor growth observed upon myeloid-specific deletion of Tet2. Our findings reveal a non-cell-intrinsic, tumor-promoting function for Tet2 and suggest that Tet2 may present a therapeutic target for the treatment of non-hematologic malignancies.


Assuntos
Carcinogênese , Proteínas de Ligação a DNA/metabolismo , Melanoma/imunologia , Células Supressoras Mieloides/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Animais , Dioxigenases , Feminino , Humanos , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Carga Tumoral , Evasão Tumoral
5.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38095856

RESUMO

The success of immune checkpoint blockade (ICB) promotes the immunotherapy to be a new pillar in cancer treatment. However, the low response rate of the ICB therapy limits its application. To increase the response rate and enhance efficacy, the ICB combination therapy has emerged and its clinical trials are increasing. Nevertheless, the gene expression profile and its pattern of ICB combination were not comprehensively studied, which limits the understanding of the ICB combination therapy and the identification of new drugs. Here, we constructed ICBcomb (http://bioinfo.life.hust.edu.cn/ICBcomb/), a comprehensive database, by analyzing the human and mouse expression data of the ICB combination therapy and comparing them between groups treated with ICB, other drugs or their combinations. ICBcomb contains 1399 samples across 29 cancer types involving 52 drugs. It provides a user-friendly web interface for demonstrating the results of the available comparisons in the ICB combination therapy datasets with five functional modules: [1, 2] the 'Dataset/Disease' modules for browsing the expression, enrichment and comparison results in each dataset or disease; [3] the 'Gene' module for inputting a gene symbol and displaying its expression and comparison results across datasets/diseases; [4] the 'Gene Set' module for GSVA/GSEA enrichment analysis on the built-in gene sets and the user-input gene sets in different comparisons; [5] the 'Immune Cell' module for immune cell infiltration comparison between different groups by immune cell abundance analysis. The ICBcomb database provides the first resource for gene expression profile and comparison in ICB combination therapy, which may provide clues for discovering the mechanism of effective combination strategies and new combinatory drugs.


Assuntos
Inibidores de Checkpoint Imunológico , Imunoterapia , Humanos , Animais , Camundongos , Bases de Dados Factuais , Redes Reguladoras de Genes
6.
Basic Res Cardiol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639887

RESUMO

Hypertrophic cardiomyopathy (HCM) constitutes the most common genetic cardiac disorder. However, current pharmacotherapeutics are mainly symptomatic and only partially address underlying molecular mechanisms. Circular RNAs (circRNAs) are a recently discovered class of non-coding RNAs and emerged as specific and powerful regulators of cellular functions. By performing global circRNA-specific next generation sequencing in cardiac tissue of patients with hypertrophic cardiomyopathy compared to healthy donors, we identified circZFPM2 (hsa_circ_0003380). CircZFPM2, which derives from the ZFPM2 gene locus, is a highly conserved regulatory circRNA that is strongly induced in HCM tissue. In vitro loss-of-function experiments were performed in neonatal rat cardiomyocytes, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and HCM-patient-derived hiPSC-CMs. A knockdown of circZFPM2 was found to induce cardiomyocyte hypertrophy and compromise mitochondrial respiration, leading to an increased production of reactive oxygen species and apoptosis. In contrast, delivery of recombinant circZFPM2, packaged in lipid-nanoparticles or using AAV-based overexpression, rescued cardiomyocyte hypertrophic gene expression and promoted cell survival. Additionally, HCM-derived cardiac organoids exhibited improved contractility upon CM-specific overexpression of circZFPM2. Multi-Omics analysis further promoted our hypothesis, showing beneficial effects of circZFPM2 on cardiac contractility and mitochondrial function. Collectively, our data highlight that circZFPM2 serves as a promising target for the treatment of cardiac hypertrophy including HCM.

7.
Virol J ; 21(1): 96, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671532

RESUMO

BACKGROUND: There is still limited research on the prognostic value of Presepsin as a biomarker for predicting the outcome of COVID-19 patients. Additionally, research on the combined predictive value of Presepsin with clinical scoring systems and inflammation markers for disease prognosis is lacking. METHODS: A total of 226 COVID-19 patients admitted to Beijing Youan Hospital's emergency department from May to November 2022 were screened. Demographic information, laboratory measurements, and blood samples for Presepsin levels were collected upon admission. The predictive value of Presepsin, clinical scoring systems, and inflammation markers for 28-day mortality was analyzed. RESULTS: A total of 190 patients were analyzed, 83 (43.7%) were mild, 61 (32.1%) were moderate, and 46 (24.2%) were severe/critically ill. 23 (12.1%) patients died within 28 days. The Presepsin levels in severe/critical patients were significantly higher compared to moderate and mild patients (p < 0.001). Presepsin showed significant predictive value for 28-day mortality in COVID-19 patients, with an area under the ROC curve of 0.828 (95% CI: 0.737-0.920). Clinical scoring systems and inflammation markers also played a significant role in predicting 28-day outcomes. After Cox regression adjustment, Presepsin, qSOFA, NEWS2, PSI, CURB-65, CRP, NLR, CAR, and LCR were identified as independent predictors of 28-day mortality in COVID-19 patients (all p-values < 0.05). Combining Presepsin with clinical scoring systems and inflammation markers further enhanced the predictive value for patient prognosis. CONCLUSION: Presepsin is a favorable indicator for the prognosis of COVID-19 patients, and its combination with clinical scoring systems and inflammation markers improved prognostic assessment.


Assuntos
Biomarcadores , COVID-19 , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , COVID-19/mortalidade , COVID-19/sangue , COVID-19/diagnóstico , Inflamação/sangue , Receptores de Lipopolissacarídeos/sangue , Fragmentos de Peptídeos/sangue , Valor Preditivo dos Testes , Prognóstico , Curva ROC , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença
8.
Nature ; 556(7699): 103-107, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29590091

RESUMO

A challenge in the treatment of Staphylococcus aureus infections is the high prevalence of methicillin-resistant S. aureus (MRSA) strains and the formation of non-growing, dormant 'persister' subpopulations that exhibit high levels of tolerance to antibiotics and have a role in chronic or recurrent infections. As conventional antibiotics are not effective in the treatment of infections caused by such bacteria, novel antibacterial therapeutics are urgently required. Here we used a Caenorhabditis elegans-MRSA infection screen to identify two synthetic retinoids, CD437 and CD1530, which kill both growing and persister MRSA cells by disrupting lipid bilayers. CD437 and CD1530 exhibit high killing rates, synergism with gentamicin, and a low probability of resistance selection. All-atom molecular dynamics simulations demonstrated that the ability of retinoids to penetrate and embed in lipid bilayers correlates with their bactericidal ability. An analogue of CD437 was found to retain anti-persister activity and show an improved cytotoxicity profile. Both CD437 and this analogue, alone or in combination with gentamicin, exhibit considerable efficacy in a mouse model of chronic MRSA infection. With further development and optimization, synthetic retinoids have the potential to become a new class of antimicrobials for the treatment of Gram-positive bacterial infections that are currently difficult to cure.


Assuntos
Antibacterianos/classificação , Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Retinoides/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Animais , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Benzoatos/química , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Benzoatos/toxicidade , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/microbiologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Gentamicinas/farmacologia , Gentamicinas/uso terapêutico , Humanos , Bicamadas Lipídicas/química , Staphylococcus aureus Resistente à Meticilina/citologia , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Dinâmica Molecular , Mutação , Naftóis/química , Naftóis/farmacologia , Naftóis/uso terapêutico , Naftóis/toxicidade , Retinoides/química , Retinoides/uso terapêutico , Retinoides/toxicidade
9.
J Epidemiol ; 34(2): 87-93, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36908115

RESUMO

BACKGROUND: Ambient particulate matter is classified as a human Class 1 carcinogen, and recent studies found a positive relationship between fine particulate matter (PM2.5) and liver cancer. Nevertheless, little is known about which specific metal constituent contributes to the development of liver cancer. OBJECTIVE: To evaluate the association of long-term exposure to metal constituents in PM2.5 with the risk of liver cancer using a Taiwanese cohort study. METHODS: A total of 13,511 Taiwanese participants were recruited from the REVEAL-HBV in 1991-1992. Participants' long-term exposure to eight metal constituents (Ba, Cu, Mn, Sb, Zn, Pb, Ni, and Cd) in PM2.5 was based on ambient measurement in 2002-2006 followed by a land-use regression model for spatial interpolation. We ascertained newly developed liver cancer (ie, hepatocellular carcinoma [HCC]) through data linkage with the Taiwan Cancer Registry and national health death certification in 1991-2014. A Cox proportional hazards model was utilized to assess the association between exposure to PM2.5 metal component and HCC. RESULTS: We identified 322 newly developed HCC with a median follow-up of 23.1 years. Long-term exposure to PM2.5 Cu was positively associated with a risk of liver cancer. The adjusted hazard ratio (HR) was 1.13 (95% confidence interval [CI], 1.02-1.25; P = 0.023) with one unit increment on Cu normalized by PM2.5 mass concentration in the logarithmic scale. The PM2.5 Cu-HCC association remained statistically significant with adjustment for co-exposures to other metal constituents in PM2.5. CONCLUSION: Our findings suggest PM2.5 containing Cu may attribute to the association of PM2.5 exposure with liver cancer.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/epidemiologia , Estudos de Coortes , Carcinoma Hepatocelular/epidemiologia , Vírus da Hepatite B , Japão , Material Particulado/efeitos adversos , Metais , Exposição Ambiental/efeitos adversos
10.
Antonie Van Leeuwenhoek ; 117(1): 83, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806744

RESUMO

An aerobic, Gram-stain-negative, motile rod bacterium, designated as SYSU BS000021T, was isolated from a black soil sample in Harbin, Heilongjiang province, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Methylobacterium, and showed the highest sequence similarity to Methylobacterium segetis KCTC 62267 T (98.51%) and Methylobacterium oxalidis DSM 24028 T (97.79%). Growth occurred at 20-37℃ (optimum, 28 °C), pH 6.0-8.0 (optimum, pH 7.0) and in the presence of 0% (w/v) NaCl. Polar lipids comprised of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminolipid and one unidentified polar lipid. The major cellular fatty acids (> 5%) were C18:0 and C18:1 ω7c and/or C18:1 ω6c. The predominant respiratory quinone was Q-10. The genomic G + C content was 68.36% based on the whole genome analysis. The average nucleotide identity (≤ 83.5%) and digital DNA-DNA hybridization (≤ 27.3%) values between strain SYSU BS000021T and other members of the genus Methylobacterium were all lower than the threshold values recommended for distinguishing novel prokaryotic species. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain SYSU BS000021T represents a novel species of the genus Methylobacterium, for which the name Methylobacterium nigriterrae sp. nov. is proposed. The type strain of the proposed novel species is SYSU BS000021T (= GDMCC 1.3814 T = KCTC 8051 T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Methylobacterium , Filogenia , RNA Ribossômico 16S , Microbiologia do Solo , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Ácidos Graxos/química , Methylobacterium/genética , Methylobacterium/classificação , Methylobacterium/isolamento & purificação , China , Hibridização de Ácido Nucleico , Análise de Sequência de DNA , Fosfolipídeos/análise
11.
Environ Toxicol ; 39(3): 1481-1493, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994612

RESUMO

BACKGROUND: Matrine has been identified to have anticancer activity in hepatocellular carcinoma (HCC). Circ_0055976 was highly expressed in HCC. Here, we investigated the function and relationship of Matrine and circ_0055976 in HCC tumorigenesis. METHODS: Cell proliferation and invasion were detected using Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine (EdU), colony formation and transwell assays, respectively. Cell aerobic glycolysis was evaluated by detecting glucose consumption, lactate production, and the ratios of ATP/ADP. Levels of genes and proteins were detected by quantitative real-time polymerase chain reaction and Western blotting. The target relationship between miR-1179 and circ_0055976 or lactate dehydrogenase A (LDHA) was analyzed by dual-luciferase reporter assay. The mouse xenograft model was established to conduct the in vivo assay. RESULTS: Matrine suppressed HCC cell proliferation, invasion and anaerobic glycolysis in vitro. Circ_0055976 was highly expressed in HCC tissues and cells, and was reduced by Matrine treatment. Moreover, overexpression of circ_0055976 reversed the anticancer effects of Matrine in HCC cells. Mechanistically, circ_0055976/miR-1179/LDHA formed an axis. Circ_0055976 knockdown or miR-1179 overexpression impaired HCC cell proliferation, invasion, and anaerobic glycolysis, which were reversed by miR-1179 inhibition or LDHA overexpression. Meanwhile, forced expression of LDHA abolished the regulatory effects of Matrine on HCC cells. In the clinic, Matrine impeded HCC tumor growth in vivo, and this effect was boosted after circ_0055976 silencing. CONCLUSION: Matrine suppressed HCC cell proliferation, invasion, and anaerobic glycolysis via circ_0055976/miR-1179/LDHA axis, providing a new insight into the clinical application of Matrine in HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Animais , Camundongos , Lactato Desidrogenase 5 , Matrinas , Transformação Celular Neoplásica , Carcinogênese , Proliferação de Células , Modelos Animais de Doenças , Linhagem Celular Tumoral
12.
Antimicrob Agents Chemother ; 67(4): e0167922, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36943064

RESUMO

Acne vulgaris is a complex skin disease involving infection by Cutibacterium acnes, inflammation, and hyperkeratinization. We evaluated the activity of the retinoid 6-[3-(adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437) and 16 other retinoid analogs as potential anti-C. acnes compounds and found that CD437 displayed the highest antimicrobial activity with an MIC against C. acnes (ATCC 6919 and HM-513) of 1 µg/mL. CD437 demonstrated an MBC of 2 µg/mL compared to up to 64 µg/mL for the retinoid adapalene and up to 16 µg/mL for tetracycline, which are commonly used clinically to treat acne. Membrane permeability assays demonstrated that exposure of C. acnes ATCC 6919 to CD437 damaged the integrity of C. acnes ATCC 6919 bacterial membranes, and this finding was confirmed with scanning electron microscopy. Additionally, CD437 downregulated the expression of C. acnes ATCC 6919 virulence factors, including the genes encoding Christie-Atkins-Munch-Petersen factor 1 (CAMP1), CAMP2, glycerol-ester hydrolase B (GehB), sialidase B, and neuraminidase. In a mouse skin infection model of C. acnes ATCC 6919, topical treatment with CD437 ameliorated skin lesions and reduced the bacterial burden in situ (P < 0.001). In human NHEK primary cells, CD437 reduced the transcriptional levels of the coding genes for inflammatory cytokines (interleukin-1α, ~10-fold; interleukin-6, ~20-fold; interleukin-8, ~30-fold; and tumor necrosis factor-alpha, ~6-fold) and downregulated the transcriptional levels of KRT10 (~10-fold), FLG (~4-fold), and TGM1 (~2-fold), indicating that CD437 can diminish inflammation and hyperkeratinization. In summary, CD437 deserves further attention for its dual function as a potential acne therapeutic that potentially acts on both the pathogen and the host.


Assuntos
Acne Vulgar , Retinoides , Camundongos , Animais , Humanos , Retinoides/metabolismo , Retinoides/uso terapêutico , Acne Vulgar/tratamento farmacológico , Acne Vulgar/microbiologia , Citocinas/metabolismo , Antibacterianos/uso terapêutico , Inflamação , Propionibacterium acnes
13.
J Cell Sci ; 134(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722977

RESUMO

The α-arrestin domain containing protein 3 (ARRDC3) is a tumor suppressor in triple-negative breast carcinoma (TNBC), a highly metastatic subtype of breast cancer that lacks targeted therapies. Thus, understanding the mechanisms and targets of ARRDC3 in TNBC is important. ARRDC3 regulates trafficking of protease-activated receptor 1 (PAR1, also known as F2R), a G-protein-coupled receptor (GPCR) implicated in breast cancer metastasis. Loss of ARRDC3 causes overexpression of PAR1 and aberrant signaling. Moreover, dysregulation of GPCR-induced Hippo signaling is associated with breast cancer progression. However, the mechanisms responsible for Hippo dysregulation remain unknown. Here, we report that the Hippo pathway transcriptional co-activator TAZ (also known as WWTR1) is the major effector of GPCR signaling and is required for TNBC migration and invasion. Additionally, ARRDC3 suppresses PAR1-induced Hippo signaling via sequestration of TAZ, which occurs independently of ARRDC3-regulated PAR1 trafficking. The ARRDC3 C-terminal PPXY motifs and TAZ WW domain are crucial for this interaction and are required for suppression of TNBC migration and lung metastasis in vivo. These studies are the first to demonstrate a role for ARRDC3 in regulating GPCR-induced TAZ activity in TNBC and reveal multi-faceted tumor suppressor functions of ARRDC3. This article has an associated First Person interview with the first author of the paper.


Assuntos
Neoplasias da Mama , Arrestinas/metabolismo , Neoplasias da Mama/genética , Feminino , Humanos , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Transdução de Sinais , Fatores de Transcrição
14.
Magn Reson Med ; 90(6): 2486-2499, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37582301

RESUMO

PURPOSE: In resting-state fMRI (rs-fMRI), the global signal average captures widespread fluctuations related to unwanted sources of variance such as motion and respiration, as well as widespread neural activity; however, relative contributions of neural and non-neural sources to the global signal remain poorly understood. This study sought to tackle this problem through the comparison of the BOLD global signal to an adjacent non-brain tissue signal, where neural activity was absent, from the same rs-fMRI scan obtained from anesthetized rats. In this dataset, motion was minimal and ventilation was phase-locked to image acquisition to minimize respiratory fluctuations. Data were acquired using three different anesthetics: isoflurane, dexmedetomidine, and a combination of dexmedetomidine and light isoflurane. METHODS: A power spectral density estimate, a voxel-wise spatial correlation via Pearson's correlation, and a co-activation pattern analysis were performed using the global signal and the non-brain tissue signal. Functional connectivity was calculated using Pearson's linear correlation on default mode network (DMN) regions. RESULTS: We report differences in the spectral composition of the two signals and show spatial selectivity within DMN structures that show an increased correlation to the global signal and decreased intra-network connectivity after global signal regression. All of the observed differences between the global signal and the non-brain tissue signal were maintained across anesthetics. CONCLUSION: These results show that the global signal is distinct from the noise contained in the tissue signal, as support for a neural contribution. This study provides a unique perspective to the contents of the global signal and their origins.


Assuntos
Dexmedetomidina , Isoflurano , Ratos , Animais , Isoflurano/farmacologia , Imageamento por Ressonância Magnética/métodos , Ruído , Mapeamento Encefálico/métodos
15.
Plant Cell Environ ; 46(7): 2078-2096, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37128741

RESUMO

Gladiolus hybridus is one of the most popular flowers worldwide. However, its corm dormancy characteristic largely limits its off-season production. Long-term cold treatment (LT), which increases sugar content and reduces abscisic acid (ABA), is an efficient approach to accelerate corm dormancy release (CDR). Here, we identified a GhbZIP30-GhCCCH17 module that mediates the antagonism between sugars and ABA during CDR. We showed that sugars promoted CDR by reducing ABA levels in Gladiolus. Our data demonstrated that GhbZIP30 transcription factor directly binds the GhCCCH17 zinc finger promoter and activates its transcription, confirmed by yeast one-hybrid, dual-luciferase (Dual-LUC), chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) and electrophoretic mobility shift assay (EMSA). GhCCCH17 is a transcriptional activator, and its nuclear localisation is altered by surcose and cytokinin treatments. Both GhbZIP30 and GhCCCH17 positively respond to LT, sugars, and cytokinin treatments. Silencing GhbZIP30 or GhCCCH17 resulted in delayed CDR by regulating ABA metabolic genes, while their overexpression promoted CDR. Taken together, we propose that the GhbZIP30-GhCCCH17 module is involved in cold- and glucose-induced CDR by regulating ABA metabolic genes.


Assuntos
Ácido Abscísico , Dormência de Plantas , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Dormência de Plantas/genética , Fatores de Transcrição/metabolismo , Citocininas , Açúcares , Regulação da Expressão Gênica de Plantas
16.
Microb Pathog ; 180: 106146, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150309

RESUMO

Talaromycosis, namely Talaromyces marneffei infection, is increasing gradually and has a high mortality rate even under antifungal therapy. Although autophagy acts differently on different pathogens, it is a promising therapeutic strategy. However, information on autophagy in macrophages and animals upon infection by T. marneffei is still limited. Therefore, several models were employed here to investigate the role of autophagy in host defense against T. marneffei, including RAW264.7 macrophages as in vitro models, different types of Caenorhabditis elegans and BALB/c mice as in vivo models. We applied the clinical T. marneffei isolate SUMS0152 in this study. T. marneffei-infected macrophages exhibit increased formation of autophagosomes. Further, macrophage autophagy promoted by rapamycin or Earle's balanced salt solution (EBSS) inhibited the viability of intracellular T. marneffei. In vivo, compared with uninfected Caenorhabditis elegans, the wild-type nematodes upregulated the expression of the autophagy-related gene lgg-1 and atg-18, and nematodes carrying GFP reporter were induced to form autophagosomes (GFP::LGG-1) after T. marneffei infection. Furthermore, the knockdown of lgg-1 significantly reduced the survival rate of T. marneffei-infected nematodes. Likewise, the autophagy activator rapamycin reduced the fungal burden and suppressed lung inflammation in a mouse model of infection. In conclusion, autophagy is essential for host defense against T. marneffei in vitro and in vivo. Therefore, autophagy may be an attractive target for developing new therapeutics to treat talaromycosis.


Assuntos
Caenorhabditis elegans , Talaromyces , Animais , Camundongos , Autofagia , Sirolimo/farmacologia
17.
Phys Rev Lett ; 130(21): 210801, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295116

RESUMO

Quantum key distribution (QKD) aims to generate secure private keys shared by two remote parties. With its security being protected by principles of quantum mechanics, some technology challenges remain towards practical application of QKD. The major one is the distance limit, which is caused by the fact that a quantum signal cannot be amplified while the channel loss is exponential with the distance for photon transmission in optical fiber. Here using the 3-intensity sending-or-not-sending protocol with the actively-odd-parity-pairing method, we demonstrate a fiber-based twin-field QKD over 1002 km. In our experiment, we developed a dual-band phase estimation and ultra-low noise superconducting nanowire single-photon detectors to suppress the system noise to around 0.02 Hz. The secure key rate is 9.53×10^{-12} per pulse through 1002 km fiber in the asymptotic regime, and 8.75×10^{-12} per pulse at 952 km considering the finite size effect. Our work constitutes a critical step towards the future large-scale quantum network.


Assuntos
Fótons , Física , Feminino , Gravidez , Humanos , Frequência Cardíaca
18.
Phys Chem Chem Phys ; 25(8): 6537-6544, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36786679

RESUMO

Two-dimensional (2D) materials are an excellent platform for surface-enhanced Raman spectroscopy (SERS). However, a poor detection sensitivity hinders their practical application. Exciton resonance (µex) can improve SERS significantly by lending intensity to nearby charge-transfer resonance. Coincidentally, for ReS2, the enhanced µex can be achieved through the injection of excited-state electrons which can adjust the energy band to the SERS detection range. Moreover, ReS2 has strong anisotropic properties, which adds an additional dimension for SERS. Therefore, ReS2 is an ideal candidate to realize highly sensitive anisotropic SERS. In this paper, the metallic T phase of ReS2 is introduced to the semiconducting Td phase by phase engineering. The photoinduced electron tunneling from the T phase to the Td phase can tune exciton emissions to the visible region, which effectively facilitates the photoinduced charge transfer processes. With RhB as the probe molecule, the synergistic resonance effects improve the limit of detection to 10-9 M with the enhancement factor up to about 108. Meanwhile, the obtained ultrasensitive SERS substrates also show good uniformity, stability as well as unique anisotropy. Our results open a new perspective in the improvement of the SERS performance.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37653354

RESUMO

Proregenerative and neuroprotective effects of antidepressants are an important topic of inquiry in neuropsychiatric research. Oxygen-glucose deprivation (OGD) mimics key aspects of ischemic injury in vitro. Here, we studied the effects of 24-h pretreatment with serotonin (5-HT), citalopram (CIT), fluoxetine (FLU), and tianeptine (TIA) on primary mouse cortical neurons subjected to transient OGD. 5-HT (50 µM) significantly enhanced neuron viability as measured by MTT assay and reduced cell death and LDH release. CIT (10 µM) and FLU (1 µM) did not increase the effects of 5-HT and neither antidepressant conferred neuroprotection in the absence of supplemental 5-HT in serum-free cell culture medium. By contrast, pre-treatment with TIA (10 µM) resulted in robust neuroprotection, even in the absence of 5-HT. Furthermore, TIA inhibited mRNA transcription of candidate genes related to cell death and hypoxia and attenuated lipid peroxidation, a hallmark of neuronal injury. Finally, deep RNA sequencing of primary neurons subjected to OGD demonstrated that OGD induces many pathways relating to cell survival, the inflammation-immune response, synaptic dysregulation and apoptosis, and that TIA pretreatment counteracted these effects of OGD. In conclusion, this study highlights the comparative strength of the 5-HT independent neuroprotective effects of TIA and identifies the molecular pathways involved.

20.
Nature ; 546(7660): 667-670, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28636595

RESUMO

Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our data show that, via RNA helicase Dhx9, Nlrp9b recognizes short double-stranded RNA stretches and forms inflammasome complexes with the adaptor proteins Asc and caspase-1 to promote the maturation of interleukin (Il)-18 and gasdermin D (Gsdmd)-induced pyroptosis. Conditional depletion of Nlrp9b or other inflammasome components in the intestine in vivo resulted in enhanced susceptibility of mice to rotavirus replication. Our study highlights an important innate immune signalling pathway that functions in intestinal epithelial cells and may present useful targets in the modulation of host defences against viral pathogens.


Assuntos
Células Epiteliais/imunologia , Células Epiteliais/virologia , Inflamassomos/metabolismo , Intestinos/citologia , Receptores Acoplados a Proteínas G/metabolismo , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/virologia , Rotavirus/imunologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/metabolismo , RNA Helicases DEAD-box/metabolismo , Células Epiteliais/metabolismo , Feminino , Imunidade Inata , Inflamassomos/química , Inflamassomos/genética , Interleucina-18/imunologia , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Ligação a Fosfato , Piroptose , RNA de Cadeia Dupla/metabolismo , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/imunologia , Rotavirus/crescimento & desenvolvimento
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