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1.
Cell ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38968937

RESUMO

Immune tolerance mechanisms are shared in cancer and pregnancy. Through cross-analyzing single-cell RNA-sequencing data from multiple human cancer types and the maternal-fetal interface, we found B7-H4 (VTCN1) is an onco-fetal immune tolerance checkpoint. We showed that genetic deficiency of B7-H4 resulted in immune activation and fetal resorption in allogeneic pregnancy models. Analogously, B7-H4 contributed to MPA/DMBA-induced breast cancer progression, accompanied by CD8+ T cell exhaustion. Female hormone screening revealed that progesterone stimulated B7-H4 expression in placental and breast cancer cells. Mechanistically, progesterone receptor (PR) bound to a newly identified -58 kb enhancer, thereby mediating B7-H4 transcription via the PR-P300-BRD4 axis. PR antagonist or BRD4 degrader potentiated immunotherapy in a murine B7-H4+ breast cancer model. Thus, our work unravels a mechanistic and biological connection of a female sex hormone (progesterone) to onco-fetal immune tolerance via B7-H4 and suggests that the PR-P300-BRD4 axis is targetable for treating B7-H4+ cancer.

2.
Nat Immunol ; 22(4): 460-470, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33767425

RESUMO

Targeting the p53-MDM2 pathway to reactivate tumor p53 is a chemotherapeutic approach. However, the involvement of this pathway in CD8+ T cell-mediated antitumor immunity is unknown. Here, we report that mice with MDM2 deficiency in T cells exhibit accelerated tumor progression and a decrease in tumor-infiltrating CD8+ T cell survival and function. Mechanistically, MDM2 competes with c-Cbl for STAT5 binding, reduces c-Cbl-mediated STAT5 degradation and enhances STAT5 stability in tumor-infiltrating CD8+ T cells. Targeting the p53-MDM2 interaction with a pharmacological agent, APG-115, augmented MDM2 in T cells, thereby stabilizing STAT5, boosting T cell immunity and synergizing with cancer immunotherapy. Unexpectedly, these effects of APG-115 were dependent on p53 and MDM2 in T cells. Clinically, MDM2 abundance correlated with T cell function and interferon-γ signature in patients with cancer. Thus, the p53-MDM2 pathway controls T cell immunity, and targeting this pathway may treat patients with cancer regardless of tumor p53 status.


Assuntos
Linfócitos T CD8-Positivos/enzimologia , Linfócitos do Interstício Tumoral/enzimologia , Neoplasias/enzimologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fator de Transcrição STAT5/metabolismo , Animais , Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/transplante , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/transplante , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Estabilidade Proteica , Proteólise , Proteínas Proto-Oncogênicas c-mdm2/genética , Fator de Transcrição STAT5/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
3.
Cell ; 165(5): 1092-1105, 2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27133165

RESUMO

Effector T cells and fibroblasts are major components in the tumor microenvironment. The means through which these cellular interactions affect chemoresistance is unclear. Here, we show that fibroblasts diminish nuclear accumulation of platinum in ovarian cancer cells, resulting in resistance to platinum-based chemotherapy. We demonstrate that glutathione and cysteine released by fibroblasts contribute to this resistance. CD8(+) T cells abolish the resistance by altering glutathione and cystine metabolism in fibroblasts. CD8(+) T-cell-derived interferon (IFN)γ controls fibroblast glutathione and cysteine through upregulation of gamma-glutamyltransferases and transcriptional repression of system xc(-) cystine and glutamate antiporter via the JAK/STAT1 pathway. The presence of stromal fibroblasts and CD8(+) T cells is negatively and positively associated with ovarian cancer patient survival, respectively. Thus, our work uncovers a mode of action for effector T cells: they abrogate stromal-mediated chemoresistance. Capitalizing upon the interplay between chemotherapy and immunotherapy holds high potential for cancer treatment.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Feminino , Fibroblastos/metabolismo , Glutationa/metabolismo , Humanos , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus
4.
PLoS Pathog ; 19(3): e1011241, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930690

RESUMO

Dengue virus (DENV) infection can induce life-threatening dengue hemorrhagic fever/dengue shock syndrome in infected patients. DENV is a threat to global health due to its growing numbers and incidence of infection in the last 50 years. During infection, DENV expresses ten structural and nonstructural proteins modulating cell responses to benefit viral replication. However, the lack of knowledge regarding the cellular proteins and their functions in enhancing DENV pathogenesis impedes the development of antiviral drugs and therapies against fatal DENV infection. Here, we identified that integrin-linked kinase (ILK) is a novel enhancing factor for DENV infection by suppressing type I interferon (IFN) responses. Mechanistically, ILK binds DENV NS1 and NS3, activates Akt and Erk, and induces NF-κB-driven suppressor of cytokine signaling 3 (SOCS3) expression. Elevated SOCS3 in DENV-infected cells inhibits phosphorylation of STAT1/2 and expression of interferon-stimulated genes (ISGs). Inhibiting ILK, Akt, or Erk activation abrogates SOCS3 expression. In DENV-infected mice, the treatment of an ILK inhibitor significantly reduces viral loads in the brains, disease severity, and mortality rate. Collectively, our results show that ILK is a potential therapeutic target against DENV infection.


Assuntos
Vírus da Dengue , Dengue , Interferon Tipo I , Animais , Camundongos , Vírus da Dengue/fisiologia , Proteínas Proto-Oncogênicas c-akt , Replicação Viral , Interferon Tipo I/uso terapêutico
5.
Immunity ; 45(3): 555-569, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27637147

RESUMO

During viral infection, sensing of cytosolic DNA by the cyclic GMP-AMP synthase (cGAS) activates the adaptor protein STING and triggers an antiviral response. Little is known about the mechanisms that determine the kinetics of activation and deactivation of the cGAS-STING pathway, ensuring effective but controlled innate antiviral responses. Here we found that the ubiquitin ligase Trim38 targets cGas for sumoylation in uninfected cells and during the early phase of viral infection. Sumoylation of cGas prevented its polyubiquitination and degradation. Trim38 also sumoylated Sting during the early phase of viral infection, promoting both Sting activation and protein stability. In the late phase of infection, cGas and Sting were desumoylated by Senp2 and subsequently degraded via proteasomal and chaperone-mediated autophagy pathways, respectively. Our findings reveal an essential role for Trim38 in the innate immune response to DNA virus and provide insight into the mechanisms that ensure optimal activation and deactivation of the cGAS-STING pathway.


Assuntos
Vírus de DNA/imunologia , DNA/metabolismo , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/metabolismo , Sumoilação/fisiologia , Viroses/metabolismo , Animais , Proteínas de Transporte/metabolismo , Cisteína Endopeptidases/metabolismo , Imunidade Inata/imunologia , Cinética , Proteínas de Membrana/metabolismo , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Transdução de Sinais/imunologia , Transdução de Sinais/fisiologia , Sumoilação/imunologia , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Ubiquitinação/imunologia , Ubiquitinação/fisiologia
6.
J Antimicrob Chemother ; 79(3): 678-682, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38319867

RESUMO

OBJECTIVES: To characterize the genetic environments of ESBL gene blaVEB-1 in mcr-positive Aeromonas strains from raw meat in China. METHODS: Whole genomes of Aeromonas strains were sequenced using the Illumina or Nanopore platforms. Genetic environments of blaVEB-1 were analysed using the BLAST program. RESULTS: The blaVEB-1 gene was detected in five Aeromonas strains carrying the mcr-7-like gene. WGS revealed that all blaVEB-1 genes were located on Aeromonas chromosome, and were carried by two novel different genomic islands named Aeromonas veronii genomic islands AveGI1 and AveGI2, as well as one transposon named Tn7690. AveGI1 is a new member of the Salmonella genomic island 1 family, incorporated into the 3'-end of mnmE (trmE). AveGI2 is a novel genomic island that has a size of 23 180 bp and is incorporated into the 3'-end of syd. The MDR regions of AveGI1 and AveGI2 are two different class 1 integrons containing 10 and five resistance genes, respectively. Tn7690 is a Tn1722 derivative containing In4-type integron and Tn5393, which harbours 10 resistance genes and integrates into different positions on the chromosomes of three strains with the capacity for mobility. CONCLUSIONS: We report chromosomally located novel MDR genomic islands and transposon that carry blaVEB-1 in mcr-positive Aeromonas strains. These genetic elements may mediate the spread of blaVEB-1 in Aeromonas, and may also evolve by capturing new antimicrobial resistance genes or other mobile genetic elements.


Assuntos
Aeromonas , Aeromonas/genética , Ilhas Genômicas , China , Integrons , Carne
7.
Aging Male ; 27(1): 2346310, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38685668

RESUMO

BACKGROUND: Whether erectile dysfunction (ED) leads to considerable stress for affected men remains unclear? In this study, we investigated whether organic ED (OED) is associated with increased risks of herpes zoster (HZ) and postherpetic neuralgia (PHN). METHODS: A representative subset of Taiwan's National Health Insurance Research Database was employed for this study. Enrollees with OED from the years 2000 to 2018 were selected. To ensure comparability between the case and control groups, we implemented 1:1 propensity score matching based on age, index year, comorbidities, and medications. RESULTS: The case group included 20,808 patients with OED, while the control group consisted of 20,808 individuals without OED. The OED group exhibited a significantly elevated risk of HZ (adjusted hazard ratio [aHR] = 1.74) and PHN (aHR = 1.56) compared to the non-OED group. CONCLUSIONS: Men experiencing OED seem to face elevated risks of HZ and PHN compared to those without OED. ED may serve as a warning sign for individuals at HZ risk.


Assuntos
Disfunção Erétil , Herpes Zoster , Neuralgia Pós-Herpética , Humanos , Masculino , Disfunção Erétil/epidemiologia , Herpes Zoster/complicações , Herpes Zoster/epidemiologia , Neuralgia Pós-Herpética/epidemiologia , Taiwan/epidemiologia , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Adulto , Estudos de Casos e Controles , Pontuação de Propensão , Bases de Dados Factuais
8.
J Am Chem Soc ; 145(34): 19049-19059, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37589099

RESUMO

Given the importance and beneficial characteristics of decorated azetidines in medicinal chemistry, efficient strategies for their synthesis are highly sought after. Herein, we report a facile synthesis of the elusive all-carbon quaternary-center-bearing azetidines. By adopting a well-orchestrated polar-radical relay strategy, ring strain release of bench-stable benzoylated 1-azabicyclo[1.1.0]butane (ABB) can be harnessed for nickel-catalyzed Suzuki Csp2-Csp3 cross-coupling with commercially available boronic acids in broad scope (>50 examples), excellent functional group tolerance, and gram-scale utility. Preliminary mechanistic studies provided insights into the underlying mechanism, wherein the ring opening of ABB with a catalytic quantity of bromide accounts for the conversion of ABB into a redox-active azetidine, which subsequently engages in the cross-coupling reaction through a radical pathway. The synergistic bromide and nickel catalysis could intriguingly be derived from a single nickel source (NiBr2). Application of the method to modify natural products, biologically relevant molecules, and pharmaceuticals has been successfully achieved as well as the synthesis of melanocortin-1 receptor (MC-1R) agonist and vesicular acetylcholine transporter (VAChT) inhibitor analogues through bioisosteric replacements of piperidine with azetidine moieties, highlighting the potential of the method in drug optimization studies. Aside from the synthesis of azetidines, we demonstrate the ancillary utility of our nickel catalytic system toward the restricted Suzuki cross-coupling of tertiary alkyl bromides with aryl boronic acids to construct all-carbon quaternary centers.

9.
J Am Chem Soc ; 145(17): 9840-9849, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37089019

RESUMO

Polysaccharides have been successfully used as immunogens for the development of vaccines against bacterial infection; however, there are no oligosaccharide-based vaccines available to date and no previous studies of their processing and presentation. We reported here the intracellular enzymatic processing and antigen presentation of an oligosaccharide-conjugate cancer vaccine prepared from the glycan of Globo-H (GH), a globo-series glycosphingolipid (GSL). This oligosaccharide-conjugate vaccine was shown to elicit antibodies against the glycan moieties of all three globo-series GSLs that are exclusively expressed on many types of cancer and their stem cells. To understand the specificity and origin of cross-reactivity of the antibodies elicited by the vaccine, we found that the vaccine is first processed by fucosidase 1 in the early endosome of dendritic cells to generate a common glycan antigen of the GSLs along with GH for MHC class II presentation. This work represents the first study of oligosaccharide processing and presentation and is expected to facilitate the design and development of glycoconjugate vaccines based on oligosaccharide antigens.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Vacinas Conjugadas , Apresentação de Antígeno , Anticorpos , Polissacarídeos , Oligossacarídeos
10.
Clin Sci (Lond) ; 137(1): 17-30, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36416117

RESUMO

Oxidative stress is vital for pathophysiology of atherosclerosis and non-alcoholic fatty liver disease (NAFLD). Monoamine oxidase (MAO) is an important source of oxidative stress in the vascular system and liver. However, the effect of MAO inhibition on atherosclerosis and NAFLD has not been explored. In the present study, MAO A and B expressions were increased in atherosclerotic plaques in human and apolipoprotein E (ApoE)-deficient mice. Inhibition of MAO B (by deprenyl), but not MAO A (by clorgyline), reduced the atheroma area in the thoracic aorta and aortic sinus in ApoE-deficient mice fed the cholesterol-enriched diet for 15 weeks. MAO B inhibition attenuated oxidative stress, expression of adhesion molecules, production of inflammatory cytokines, and macrophage infiltration in atherosclerotic plaques and decreased plasma triglyceride and low-density lipoprotein (LDL) cholesterol concentrations. MAO B inhibition had no therapeutic effect on restenosis in the femoral artery wire-induced injury model in C57BL/6 mice. In the NAFLD mouse model, MAO B inhibition reduced lipid droplet deposition in the liver and hepatic total cholesterol and triglyceride levels in C57BL/6 mice fed high-fat diets for 10 weeks. Key enzymes for triglyceride and cholesterol biosynthesis (fatty acid synthase and 3-hydroxy-3-methylglutaryl-CoA reductase, HMGCR) and inflammatory markers were inhibited, and cholesterol clearance was up-regulated (increased LDL receptor expression and reduced proprotein convertase subtilisin/kexin type 9, PCSK9, expression) by MAO B inhibition in the liver. These results were also demonstrated in the HepG2 liver cell model. Our data suggest that MAO B inhibition is a potential and novel treatment for atherosclerosis and NAFLD.


Assuntos
Aterosclerose , Hipercolesterolemia , Hepatopatia Gordurosa não Alcoólica , Placa Aterosclerótica , Camundongos , Humanos , Animais , Placa Aterosclerótica/metabolismo , Pró-Proteína Convertase 9/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Monoaminoxidase/metabolismo , Camundongos Endogâmicos C57BL , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Colesterol/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Hipercolesterolemia/metabolismo , Apolipoproteínas E
11.
Macromol Rapid Commun ; 44(1): e2200297, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35621302

RESUMO

Molecules based on benzimidazolone-dioxazine are known as blue/violet pigments and have been commercialized for decades. However, unfavorable solubility limits the application of these structures as building blocks of conjugated polymers despite their low band gaps. Herein, a series of donor-acceptor conjugated polymers containing soluble benzimidazolone-dioxazine structures as the acceptors and oligothiophene as donors are synthesized and investigated. With increasing numbers of thiophene rings, the steric hindrance diminishes and high molecular weight polymers can be achieved, leading to an improved performance in organic field effect transistor devices. The hole mobility of polymers with three to six thiophene units is in the order of 10-1 cm2 V-1 s -1 . Among all the polymers, polymer P3 with three thiophene units between benzimidazolone-dioxazine structures shows the best hole mobility of 0.4 cm2 V-1 s -1 . Grazing-incidence wide-angle X-ray scattering results reveal that the high mobility of organic field-effect transistors (OFETs) can be accredited by matched donor-acceptor packing in the solid thin films.


Assuntos
Bandagens , Benzimidazóis , Polímeros , Tiofenos
12.
Phys Chem Chem Phys ; 25(24): 16559-16569, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37309184

RESUMO

The coexistence of spin-orbit coupling and piezoelectricity in a single material may have potential application in multifunctional devices, including spintronics, nanorobotics and piezotronics. Spin-orbit coupling provides a new means to manipulate electron's spin without an additional external magnetic field, while piezoelectricity refers to the interplay between mechanical stresses and electric polarization. Using first-principles calculations, the structural, electronic, optical, spin, and piezoelectric properties of the Janus Ge2XY (X ≠ Y = P, As, Sb, and Bi) monolayers were systematically investigated. All the Ge2XY are energetically and dynamically stable in the α phase. At the GW level, Ge2AsSb, Ge2AsBi, and Ge2SbBi have direct fundamental band gaps of 0.65, 0.64, and 0.91 eV. At the GW + BSE level, their optical gaps are 0.42, 0.45, and 0.63 eV, and the optical absorption coefficients can reach about 10-5 cm-1 in the infrared light region, which reveals that they have potential for application in infrared photodetectors. For Ge2PBi, Ge2AsBi, and Ge2SbBi containing the heavy Bi element, the lowermost conduction band and uppermost valence band have large spin splitting along the M-K and K-Γ lines, and the bands near the Fermi level possess Rashba spin splitting at the Γ point. Ge2PBi and Ge2SbBi have both large in-plane piezoelectric coefficients d11 (-0.75 and -3.18 pm V-1) and out-of-plane piezoelectric coefficients d31 (0.37 and 0.30 pm V-1). Our findings are helpful to understand the mechanism of the spin-orbit physics and piezoelectricity of Janus Ge2XY monolayers and guide experiments in exploring novel multifunctional materials.

13.
Surg Endosc ; 37(12): 9173-9182, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37833508

RESUMO

BACKGROUND: In this retrospective cohort study, we assessed the utility of laparoscopic surgery for diagnostic and therapeutic purposes in patients with anterior abdominal stab wounds (AASWs). We also investigated patient characteristics that might suggest a greater suitability of laparoscopic interventions. METHODS: Over a 25-year span, we analyzed AASW patients who had operations, categorizing them based on the presence of significant intra-abdominal injuries and whether they received laparoscopic surgery or laparotomy. We compared variables such as preoperative conditions, surgical details, and postoperative outcomes. We further evaluated the criteria indicating the necessity of direct laparotomies and traits linked to overlooked injuries in laparoscopic surgeries. RESULTS: Of 142 AASWs surgical patients, laparoscopic surgery was conducted on 89 (62.7%) patients. Only 2 (2.2%) had overlooked injuries after the procedure. Among patients without significant injuries, those receiving laparoscopic surgery had less blood loss than those receiving laparotomy (30.0 vs. 150.0 ml, p = 0.004). Patients who underwent laparoscopic surgery also had shorter hospital stays (significant injuries: 6.0 vs. 11.0 days, p < 0.001; no significant injuries: 5.0 vs. 6.5 days, p = 0.014). Surgical complications and overlooked injury rates were comparable between both surgical methods. Bowel evisceration correlated with higher laparotomy odds (odds ratio = 16.224, p < 0.001), while omental evisceration did not (p = 0.107). CONCLUSIONS: Laparoscopy is a safe and effective method for patients with AASWs, fulfilling both diagnostic and therapeutic needs. For stable AASW patients, laparoscopy could be the preferred method, reducing superfluous nontherapeutic laparotomies.


Assuntos
Traumatismos Abdominais , Laparoscopia , Ferimentos Penetrantes , Ferimentos Perfurantes , Humanos , Estudos Retrospectivos , Ferimentos Perfurantes/cirurgia , Ferimentos Perfurantes/diagnóstico , Laparoscopia/métodos , Ferimentos Penetrantes/cirurgia , Abdome/cirurgia , Traumatismos Abdominais/cirurgia , Laparotomia/métodos
14.
Neoplasma ; 70(1): 82-93, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36660797

RESUMO

HOXA5, as a transcription factor, plays an important role in a variety of malignant tumors. Nevertheless, its biological role in cervical squamous cell carcinoma (CSCC) is largely unknown. In our study, we aimed to explore the function of HOXA5 in CSCC and its molecular mechanism. Immunohistochemistry showed that HOXA5 expression was downregulated in human CSCC tissues and HOXA5 staining was negatively correlated with tumor size and histological grade of CSCC. Ectopic expression of HOXA5 inhibited proliferative and metastatic abilities of CSCC cells in vitro and in vivo. Furthermore, overexpression of HOXA5 inhibited the cell cycle by arresting the S/G2 phase by flow cytometry and that was related to the downregulation of Cyclin A. Further study showed that HOXA5 suppressed EMT by inhibiting the ß-catenin/Snail signaling resulting in reduced metastasis of CSCC cells. Altogether, our results suggested that HOXA5 inhibited the proliferation and metastasis via repression of the ß-catenin/Snail pathway, proposing the potential role of HOXA5 in the prevention and treatment of CSCC.


Assuntos
Carcinoma de Células Escamosas , Proteínas de Homeodomínio , Neoplasias do Colo do Útero , Feminino , Humanos , beta Catenina/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Homeodomínio/genética , Transdução de Sinais , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
15.
Proc Natl Acad Sci U S A ; 117(35): 21568-21575, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817552

RESUMO

The DNA sensor cGMP-AMP synthase (cGAS) senses cytosolic microbial or self DNA to initiate a MITA/STING-dependent innate immune response. cGAS is regulated by various posttranslational modifications at its C-terminal catalytic domain. Whether and how its N-terminal unstructured domain is regulated by posttranslational modifications remain unknown. We identified the acetyltransferase KAT5 as a positive regulator of cGAS-mediated innate immune signaling. Overexpression of KAT5 potentiated viral-DNA-triggered transcription of downstream antiviral genes, whereas a KAT5 deficiency had the opposite effects. Mice with inactivated Kat5 exhibited lower levels of serum cytokines in response to DNA virus infection, higher viral titers in the brains, and more susceptibility to DNA-virus-induced death. Mechanistically, KAT5 catalyzed acetylation of cGAS at multiple lysine residues in its N-terminal domain, which promoted its DNA-binding ability. Our findings suggest that KAT5-mediated cGAS acetylation at its N terminus is important for efficient innate immune response to DNA virus.


Assuntos
Infecções por Vírus de DNA/imunologia , Vírus de DNA/imunologia , Lisina Acetiltransferase 5/imunologia , Nucleotidiltransferases/imunologia , Acetilação , Animais , GMP Cíclico/metabolismo , Infecções por Vírus de DNA/genética , Infecções por Vírus de DNA/metabolismo , Vírus de DNA/genética , Feminino , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Interferon beta/imunologia , Lisina Acetiltransferase 5/genética , Lisina Acetiltransferase 5/metabolismo , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Proteínas Virais/metabolismo
16.
Arthroscopy ; 39(3): 662-669, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36328339

RESUMO

PURPOSE: The purpose of this study was to investigate biomechanical differences of medial patellofemoral ligament (MPFL) reconstruction, medial quadriceps tendon femoral ligament (MQTFL) reconstruction, and a combination of these techniques to restore lateral patellar constraint and contact pressures. METHODS: Eight fresh frozen cadaver knees were mounted to a custom jig with physiological quadriceps tendon loading. Flexion angles and contact pressure (CP) were dynamically measured using Tekscan® pressure sensors and Polhemus® Liberty 6 degree of freedom (6DOF) positioning sensors in the following conditions: 1) intact 2) MPFL and MQTFL deficient, 3) MPFL reconstructed, 4) Combined MPFL + MQTFL reconstructed, and 5) MQTFL reconstructed. Lateral patellar translation was tested using horizontally directed 30 N force applied at 30° of knee flexion. The knees were flexed in dynamic fashion, and CP values were recorded for 10°, 20°, 30°, 50°, 70°, and 90° degrees of flexion. Group differences were assessed with ANOVA's followed by pairwise comparisons with Bonferroni correction. RESULTS: MPFL (P = .002) and combined MPFL/MQTFL (P = .034) reconstruction significantly reduced patellar lateralization from +19.28% (9.78%, 28.78%) in the deficient condition to -17.57% (-27.84%, -7.29%) and -15.56% (-33.61%, 2.30%), respectively. MPFL reconstruction was most restrictive and MQTFL reconstruction the least -7.29% (-22.01%, 7.45%). No significant differences were found between the three reconstruction techniques. Differences in CP between the three reconstruction techniques were not significant (<.02 MPa) at all flexion angles. CONCLUSION: The present study found no significant difference for patellar lateralization and patellofemoral CP between MPFL, combined MPFL/MQTFL, and MQTFL reconstruction. All 3 techniques resulted in stronger lateral patellar constraint compared to the native state, while the MQTFL reconstruction emulated the intact state the closest. CLINICAL RELEVANCE: Various surgical techniques for medial patellofemoral complex reconstruction can restore patellar stability with similar patellofemoral articular pressures.


Assuntos
Patela , Articulação Patelofemoral , Humanos , Patela/cirurgia , Fenômenos Biomecânicos , Articulação Patelofemoral/cirurgia , Articulação Patelofemoral/fisiologia , Articulação do Joelho/cirurgia , Tendões , Ligamentos Articulares/cirurgia , Cadáver
17.
J Clin Ultrasound ; 51(4): 731-738, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36708314

RESUMO

BACKGROUND: Our aim was to explore the clinical benefit of intraoperative ultrasound in decompressive craniectomy (DC) for traumatic brain injury (TBI). METHODS: From January 1, 2018, through April 30, 2021, 54 patients who developed acute subdural hematoma (SDH) due to blunt injury and underwent DC with or without intraoperative ultrasound assistance were retrospectively included in our study. Logistic regression analyses were performed to compare the therapeutic efficacy in the two groups. RESULTS: In the ultrasound group (14 patients, 25.93%), intraoperative ultrasound was used for assisting hematoma removal and/or ventriculostomy during DC. In the control group (40 patients, 74.07%), ultrasound was not used during the operation and ventriculostomy was not performed. No statistically significant differences in age, sex, initial Glasgow Coma Scale (GCS) score, blood loss, postoperative intracranial pressure (ICP), duration of hyperosmolar therapy, or Glasgow Outcome Scale Extended (GOS-E) score 6 months after injury were observed. No mortality was recorded in the ultrasound group. The mortality rate in the control group during hospitalization was 25% (p < 0.05). CONCLUSIONS: Intraoperative ultrasound is helpful for intracranial hematoma removal and ventriculostomy with cerebrospinal fluid drainage and decreases mortality in experienced hands. The reason for higher mortality rate in the control group might result from poor hematoma clearance rate and poor postoperative intracranial pressure control. It is a useful tool for diagnosing and assisting with treatment in cases of TBI.


Assuntos
Lesões Encefálicas Traumáticas , Craniectomia Descompressiva , Humanos , Estudos Retrospectivos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/cirurgia , Escala de Coma de Glasgow , Hemorragia Cerebral , Hematoma/diagnóstico por imagem , Hematoma/cirurgia , Resultado do Tratamento
18.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36834609

RESUMO

The DEAD-box proteins, one family of RNA-binding proteins (RBPs), participate in post-transcriptional regulation of gene expression with multiple aspects. Among them, DDX6 is an essential component of the cytoplasmic RNA processing body (P-body) and is involved in translational repression, miRNA-meditated gene silencing, and RNA decay. In addition to the cytoplasmic function, DDX6 is also present in the nucleus, but the nuclear function remains unknown. To decipher the potential role of DDX6 in the nucleus, we performed mass spectrometry analysis of immunoprecipitated DDX6 from a HeLa nuclear extract. We found that adenosine deaminases that act on RNA 1 (ADAR1) interact with DDX6 in the nucleus. Utilizing our newly developed dual-fluorescence reporter assay, we elucidated the DDX6 function as negative regulators in cellular ADAR1p110 and ADAR2. In addition, depletion of DDX6 and ADARs results in the opposite effect on facilitation of RA-induced differentiation of neuronal lineage cells. Our data suggest the impact of DDX6 in regulation of the cellular RNA editing level, thus contributing to differentiation in the neuronal cell model.


Assuntos
RNA Helicases DEAD-box , MicroRNAs , Humanos , RNA Helicases DEAD-box/metabolismo , Proteínas Proto-Oncogênicas/genética , MicroRNAs/genética , Regulação da Expressão Gênica , Diferenciação Celular , Adenosina Desaminase/metabolismo
19.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38203509

RESUMO

Vascular endothelial growth factor (VEGF) plays a significant role as a pro-angiogenic and pro-permeability factor within the kidney. Bevacizumab is a pharmaceutical monoclonal anti-VEGF antibody that inhibits the growth of new blood vessels, which blocks blood supply and thereby restricts tumor growth. Thus, we conducted a nationwide study to explore the risk of chronic kidney disease (CKD) development in Taiwan residents after bevacizumab therapy. We drew data from the extensive National Health Insurance Research Database (NHIRD), which encompasses data from >99% of Taiwan's population from 1995 onwards. Individuals who received bevacizumab between 2012-2018 were identified as the bevacizumab cohort, with the index date set at the first usage. We randomly selected dates within the study period for the control group to serve as index dates. We excluded patients with a history of CKD prior to the index date or those <20 years old. In both cohorts, patients' propensity scores matched in a 1:1 ratio based on sex, age, index year, income, urbanization level, comorbidities, and medications. We found patients treated with bevacizumab had a significantly higher risk of contracting CKD than patients without bevacizumab (adjusted hazard ratio = 1.35, 95% confidence interval = 1.35-1.73). The risk of CKD was 1.35-fold higher in participants with bevacizumab treatment than those in the control group. These findings suggest that close monitoring of CKD development after bevacizumab administration is needed.


Assuntos
Insuficiência Renal Crônica , Fator A de Crescimento do Endotélio Vascular , Humanos , Adulto Jovem , Adulto , Bevacizumab/efeitos adversos , Estudos Retrospectivos , Taiwan/epidemiologia , Insuficiência Renal Crônica/epidemiologia
20.
Angew Chem Int Ed Engl ; 62(31): e202303896, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148158

RESUMO

Mimicking the active site and the substrate binding cavity of the enzyme to achieve specificity in catalytic reactions is an essential challenge. Herein, porous coordination cages (PCCs) with intrinsic cavities and tunable metal centers have proved the regulation of reactive oxygen species (ROS) generating pathways as evidenced by multiple photo-induced oxidations. Remarkably, in the presence of the Zn4 -µ4 -O center, PCC converted dioxygen molecules from triplet to singlet excitons, whereas the Ni4 -µ4 -O center promoted the efficient dissociation of electrons and holes to conduct electron transfer towards substrates. Accordingly, the distinct ROS generation behavior of PCC-6-Zn and PCC-6-Ni enables the conversion of O2 to 1 O2 and O2 ⋅- , respectively. In contrast, the Co4 -µ4 -O center combined the 1 O2 and O2 ⋅- together to generate carbonyl radicals, which in turn reacted with the oxygen molecules. Harnessing the three oxygen activation pathways, PCC-6-M (M=Zn/Ni/Co) display specific catalytic activities in thioanisole oxidation (PCC-6-Zn), benzylamine coupling (PCC-6-Ni), and aldehyde autoxidation (PCC-6-Co). This work not only provides fundamental insights into the regulation of ROS generation by a supramolecular catalyst but also demonstrates a rare example of achieving reaction specificity through mimicking natural enzymes by PCCs.


Assuntos
Metais , Oxigênio , Espécies Reativas de Oxigênio , Metais/química , Oxirredução , Oxigênio/química
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