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1.
Cell ; 187(7): 1701-1718.e28, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38503283

RESUMO

Biomolecules incur damage during stress conditions, and damage partitioning represents a vital survival strategy for cells. Here, we identified a distinct stress granule (SG), marked by dsRNA helicase DHX9, which compartmentalizes ultraviolet (UV)-induced RNA, but not DNA, damage. Our FANCI technology revealed that DHX9 SGs are enriched in damaged intron RNA, in contrast to classical SGs that are composed of mature mRNA. UV exposure causes RNA crosslinking damage, impedes intron splicing and decay, and triggers DHX9 SGs within daughter cells. DHX9 SGs promote cell survival and induce dsRNA-related immune response and translation shutdown, differentiating them from classical SGs that assemble downstream of translation arrest. DHX9 modulates dsRNA abundance in the DHX9 SGs and promotes cell viability. Autophagy receptor p62 is activated and important for DHX9 SG disassembly. Our findings establish non-canonical DHX9 SGs as a dedicated non-membrane-bound cytoplasmic compartment that safeguards daughter cells from parental RNA damage.


Assuntos
RNA , Grânulos de Estresse , Citoplasma , RNA Mensageiro/genética , Estresse Fisiológico , Humanos , Células HeLa
2.
Mol Cell ; 82(11): 2032-2049.e7, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35460603

RESUMO

Virus infection modulates both host immunity and host genomic stability. Poly(ADP-ribose) polymerase 1 (PARP1) is a key nuclear sensor of DNA damage, which maintains genomic integrity, and the successful application of PARP1 inhibitors for clinical anti-cancer therapy has lasted for decades. However, precisely how PARP1 gains access to cytoplasm and regulates antiviral immunity remains unknown. Here, we report that DNA virus induces a reactive nitrogen species (RNS)-dependent DNA damage and activates DNA-dependent protein kinase (DNA-PK). Activated DNA-PK phosphorylates PARP1 on Thr594, thus facilitating the cytoplasmic translocation of PARP1 to inhibit the antiviral immunity both in vitro and in vivo. Mechanistically, cytoplasmic PARP1 interacts with and directly PARylates cyclic GMP-AMP synthase (cGAS) on Asp191 to inhibit its DNA-binding ability. Together, our findings uncover an essential role of PARP1 in linking virus-induced genome instability with inhibition of host immunity, which is of relevance to cancer, autoinflammation, and other diseases.


Assuntos
Antivirais , Nucleotidiltransferases , Antivirais/farmacologia , Citoplasma/genética , Citoplasma/metabolismo , DNA , Dano ao DNA , Instabilidade Genômica , Humanos , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo
3.
Nat Immunol ; 17(4): 397-405, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26928339

RESUMO

The signaling adaptor TRAF3 is a highly versatile regulator of both innate immunity and adaptive immunity, but how its phosphorylation is regulated is still unknown. Here we report that deficiency in or inhibition of the conserved serine-threonine kinase CK1ɛ suppressed the production of type I interferon in response to viral infection. CK1ɛ interacted with and phosphorylated TRAF3 at Ser349, which thereby promoted the Lys63 (K63)-linked ubiquitination of TRAF3 and subsequent recruitment of the kinase TBK1 to TRAF3. Consequently, CK1ɛ-deficient mice were more susceptible to viral infection. Our findings establish CK1ɛ as a regulator of antiviral innate immune responses and indicate a novel mechanism of immunoregulation that involves CK1ɛ-mediated phosphorylation of TRAF3.


Assuntos
Caseína Quinase 1 épsilon/imunologia , Imunidade Inata/imunologia , Interferon beta/imunologia , Fator 3 Associado a Receptor de TNF/imunologia , Animais , Caseína Quinase 1 épsilon/antagonistas & inibidores , Caseína Quinase 1 épsilon/genética , Ensaio de Imunoadsorção Enzimática , Células HEK293 , Células HeLa , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Humanos , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Interferon beta/biossíntese , Espectrometria de Massas , Camundongos , Camundongos Knockout , Fosforilação , Proteínas Serina-Treonina Quinases , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Rhabdoviridae/imunologia , Fator 3 Associado a Receptor de TNF/genética , Ubiquitinação , Vesiculovirus/imunologia , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/imunologia
4.
Small ; 20(2): e2304721, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670209

RESUMO

Wide bandgap semiconductors, particularly In2 O3 :Sn (ITO), are widely used as transparent conductive electrodes in optoelectronic devices. Nevertheless, due to the strohave beenng scattering probability of high-concentration oxygen vacancy (VO ) defects, the mobility of ITO is always lower than 40 cm2  V-1  s-1 . Recently, hydrogen-doped In2 O3 (In2 O3 :H) films have been proven to have high mobility (>100 cm2  V-1  s-1 ), but the origin of this high mobility is still unclear. Herein, a high-resolution electron microscope and theoretical calculations are employed to investigate the atomic-scale mechanisms behind the high carrier mobility in In2 O3 :H films. It is found that VO can cause strong lattice distortion and large carrier scattering probability, resulting in low carrier mobility. Furthermore, hydrogen doping can simultaneously reduce the concentration of VO , which accounts for high carrier mobility. The thermal stability and acid-base corrosion mechanism of the In2 O3 :H film are investigated and found that hydrogen overflows from the film at high temperatures (>250 °C), while acidic or alkaline environments can cause damage to the In2 O3 grains themselves. Overall, this work provides insights into the essential reasons for high carrier mobility in In2 O3 :H and presents a new research approach to the doping and stability mechanisms of transparent conductive oxides.

5.
Nature ; 563(7729): 131-136, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30356214

RESUMO

Accurate repair of DNA double-stranded breaks by homologous recombination preserves genome integrity and inhibits tumorigenesis. Cyclic GMP-AMP synthase (cGAS) is a cytosolic DNA sensor that activates innate immunity by initiating the STING-IRF3-type I IFN signalling cascade1,2. Recognition of ruptured micronuclei by cGAS links genome instability to the innate immune response3,4, but the potential involvement of cGAS in DNA repair remains unknown. Here we demonstrate that cGAS inhibits homologous recombination in mouse and human models. DNA damage induces nuclear translocation of cGAS in a manner that is dependent on importin-α, and the phosphorylation of cGAS at tyrosine 215-mediated by B-lymphoid tyrosine kinase-facilitates the cytosolic retention of cGAS. In the nucleus, cGAS is recruited to double-stranded breaks and interacts with PARP1 via poly(ADP-ribose). The cGAS-PARP1 interaction impedes the formation of the PARP1-Timeless complex, and thereby suppresses homologous recombination. We show that knockdown of cGAS suppresses DNA damage and inhibits tumour growth both in vitro and in vivo. We conclude that nuclear cGAS suppresses homologous-recombination-mediated repair and promotes tumour growth, and that cGAS therefore represents a potential target for cancer prevention and therapy.


Assuntos
Núcleo Celular/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Nucleotidiltransferases/metabolismo , Reparo de DNA por Recombinação , Transporte Ativo do Núcleo Celular , Adulto , Animais , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/enzimologia , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Feminino , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Nucleotidiltransferases/deficiência , Fosforilação , Ftalazinas/farmacologia , Piperazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/metabolismo , Ligação Proteica/efeitos dos fármacos , Reparo de DNA por Recombinação/genética , Quinases da Família src/metabolismo
6.
BMC Pulm Med ; 23(1): 449, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985983

RESUMO

BACKGROUND: High-flow nasal cannula (HFNC) oxygen therapy is essentially a constant-flow, noninvasive respiratory support system similar to a noninvasive ventilator operating in constant-flow mode. The clinical outcome of HFNC oxygen therapy is strongly associated with the pressure generated by high-flow gas and the patient's comfort level. This study was performed to explore the relevant factors affecting pressure and comfort of HFNC oxygen therapy in vivo. METHODS: Thirty-five healthy volunteers were enrolled in the trial. They underwent placement of nasal cannulas of various inner diameters (3, 4 or 5 mm) and treatment with different HFNC devices [HFT-300 (Weishengkang Medical Technology Co., Ltd., Jiangsu China) or H-80 M (BMC Medical Co., Ltd., Beijing China)],and the nasal airway pressure and comfort were assessed. Multiple linear regression was used to determine predictors of airway pressure. RESULTS: Multiple linear regression showed that the end-expiratory pressure was associated with the flow rate, sex, height, and cannula size. The end-expiratory pressure increased by 0.6 cmH2O per 1-mm increase in cannula diameter, decreased by 0.3 cmH2O per 10-cm increase in participant height (with a 0.35 cmH2O decrease for men), and increased by 1 cmH2O when the flow rate increased by 10 L/min (R2 = 0.75, P < 0.05 for all variables in model). In addition, the pressure generated by the H-80 M device was higher than that generated by the HFT-300 device (P < 0.05). Discomfort manifested as difficulty in expiration, and its severity increased as the cannula diameter increased; however there was no significant difference in comfort between the two HFNC devices (P > 0.05). CONCLUSION: In volunteers undergoing HFNC oxygen therapy, the nasal cannula diameter, flow rate, sex, height, and device model can affect the nasal airway pressure, and the nasal catheter diameter and flow rate can affect comfort. These factors should be given close attention in clinical practice. TRIAL REGISTRATION: ChiCTR2300068313 (date of first registration: 14 February 2023,  https://www.chictr.org.cn ).


Assuntos
Cânula , Oxigenoterapia , Humanos , Masculino , Catéteres , Oxigênio , Voluntários
7.
J Clin Lab Anal ; 36(10): e24673, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36036748

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) accounts for 85%-90% of primary liver cancer. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by targeting the 3'UTR of mRNA. Abnormal expression and regulation of miRNAs are involved in the occurrence and progression of HCC, and miRNAs can also play a role in the diagnosis and treatment of HCC as oncogenes or tumor suppressors. METHODS: In the past decades, a large number of studies have shown that miRNAs play an essential regulatory role in HCC and have potential as biomarkers for HCC. We reviewed the literature to summarize these studies. RESULTS: By reviewing the literature, we retrospected the roles of miRNAs in the development, diagnosis, treatment, and prognosis of HCC, and put forward prospects for the further research on miRNAs in the precision treatment of HCC. CONCLUSION: MicroRNAs are important regulators and biomarkers in the occurrence, progression, outcome, and treatment of HCC, and can provide new targets and strategies for improving the therapeutic effect of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Regiões 3' não Traduzidas , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico
8.
Clin Nephrol ; 96(3): 155-164, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33993908

RESUMO

OBJECTIVE: To investigate the changes in Treg and Th17 cells and explore the significance of Treg/Th17 balance in adult primary membranous nephropathy (PMN) patients. MATERIALS AND METHODS: A total of 60 PMN patients and 50 healthy adults from June 2013 to October 2016 were enrolled in this study. The levels of Treg, Th17, and related cytokines were assessed. Pearson correlation was used for conducting correlation analysis. RESULTS: There was a significant increase in Th17 frequencies and IL-17 (Th17-related cytokines) in the peripheral blood mononuclear cells (PBMCs), as well as a significant decrease in Treg frequencies and IL-10 (Treg-related cytokines). The IL-17 concentrations in the peripheral blood of PMN patients were positively correlated with urinary protein, while IL-10 levels were negatively correlated with urinary protein. Protein expression of Treg transcription factor (Foxp3) was significantly low in the renal tissues of PMN patients, while the expression of IL-17 was much higher. Th17/Treg imbalance was reversed to normal after effective treatment with tacrolimus in 15 PMN patients. CONCLUSION: These results suggested the existence of Treg/Th17 imbalance in PMN patients, showing the importance of Treg/Th17 imbalance in PMN pathogenesis.


Assuntos
Glomerulonefrite Membranosa , Células Th17 , Adulto , Citocinas , Fatores de Transcrição Forkhead , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/tratamento farmacológico , Humanos , Leucócitos Mononucleares , Linfócitos T Reguladores
9.
Cell Mol Biol (Noisy-le-grand) ; 66(1): 49-54, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32359383

RESUMO

The purpose of this study was to investigate the effect of liposomal clodronate combined with Cisplatin or Sorafenib on the FOXQ1 expression and biological function of hepatocellular carcinoma cell lines.  The expression of FOXQ1 was determined in normal hepatic cell line and hepatocellular carcinoma cell lines using quantitative real-time polymerase chain reaction (qRT-PCR). HepG2 and MHCC97H cells were administered low, medium and high concentrations of cisplatin (3, 5 and 7 µg/ml) or Sorafenib (2, 7 and 20 µg/ml) in combination with liposomal clodronate (LC, 20µg/ml), and the expression of FOXQ1 in each group was determined. Cell migration, MTT and transwell assays were used to determine the effects of the treatments on biological functions of HepG2 and MHCC97H cells. qRT-PCR showed that the expression of FOXQ1 mRNA was higher in the four hepatocellular carcinoma cell lines than in normal cells, and the expression of FOXQ1 mRNA in HepG2 and MHCC97H cells were more dominant. All the tested doses of Cisplatin, but only high dose Sorafenib down-regulated the expression of FOXQ1. However, Sorafenib at low and medium concentrations had no significant effect on the expression of FOXQ1. When Cisplatin or Sorafenib was administered in combination with LC, the expression level of FOXQ1 was significantly reduced. Cell migration, MTT and transwell assays showed that proliferation, migration and invasion were inhibited when each drug was administered alone, but was stronger when the drugs were combined with liposomal clodronate.Liposomal clodronate combined with Cisplatin or Sorafenib down-regulates the expression of FOXQ1 in HepG2 and MHCC97H hepatoma cells, and inhibits their proliferation, migration and invasion.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Movimento Celular , Cisplatino/uso terapêutico , Ácido Clodrônico/uso terapêutico , Fatores de Transcrição Forkhead/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Ácido Clodrônico/farmacologia , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Lipossomos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sorafenibe/farmacologia
10.
Am J Otolaryngol ; 40(4): 573-576, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31109803

RESUMO

PURPOSE: Metabolic syndrome (MetS) was reported to a risk factor of developing idiopathic sudden sensorineural hearing loss (ISSNHL), but limited data exist on its effect on the recovery. The purpose of this study was to evaluate the impact of (MetS) and its components on recovery of patients with ISSNHL. MATERIAL AND METHODS: 228 ISSNHL patients were divided into MetS group and Non-MetS group according to the diagnostic criteria of MetS, and demographic and clinical characteristics and hearing recovery were reviewed between two groups. RESULTS: In total, 86 (37.7%) patients in MetS group, and 142 (62.3%) patients in Non-MetS group. The rate of hypertension, diabetes mellitus, low HDL-C, high TG and obesity were significantly higher in the MetS group than those in the Non-MetS group (P < 0.05). The complete recovery rate and partial recovery rate were significantly lower in the MetS group than those in the Non-MetS group. According to the multivariate analysis, MetS was significantly associated with a poor prognosis; high initial hearing threshold and presence of diabetes mellitus were correlated with a poor prognosis (P < 0.05). CONCLUSIONS: These results suggest that MetS has a negative impact on the hearing recovery of ISSNHL. High initial hearing threshold and diabetes mellitus were indictors of a poor prognosis of ISSNHL.


Assuntos
Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/etiologia , Perda Auditiva Súbita/fisiopatologia , Audição , Síndrome Metabólica/complicações , Recuperação de Função Fisiológica , Adulto , Diabetes Mellitus , Limiar Diferencial , Feminino , Humanos , Hiperlipidemias , Hipertensão , Masculino , Pessoa de Meia-Idade , Obesidade , Prognóstico , Fatores de Risco
11.
J Infect Dis ; 218(2): 312-323, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29228365

RESUMO

Tuberculosis, caused by Mycobacterium tuberculosis infection, remains a global threat to human health, but knowledge of the molecular mechanisms underlying the pathogenesis of tuberculosis is still limited. Although Notch4, a member of the Notch receptor family, is involved in the initiation of mammary tumors, its function in M. tuberculosis infection remains unclear. In this study, we found that Notch4-deficient mice were more resistant to M. tuberculosis infection, with a much lower bacterial burden and fewer pathological changes in the lungs. Notch4 inhibited M. tuberculosis-induced production of proinflammatory cytokines by interaction with TAK1 and inhibition of its activation. Furthermore, we found that Notch intracellular domain 4 prevented TRAF6 autoubiquitination and suppressed TRAF6-mediated TAK1 polyubiquitination. Finally, Notch inhibitors made mice more resistant to M. tuberculosis infection. These results suggest that Notch4 is a negative regulator of M. tuberculosis-induced inflammatory response, and treatment with a Notch inhibitor could serve as a new therapeutic strategy for tuberculosis.


Assuntos
Regulação da Expressão Gênica , MAP Quinase Quinase Quinases/metabolismo , Receptor Notch4/metabolismo , Tuberculose Pulmonar/patologia , Animais , Carga Bacteriana , Citocinas/análise , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Inflamação/patologia , Pulmão/microbiologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Receptor Notch4/deficiência , Fator 6 Associado a Receptor de TNF/metabolismo , Tuberculose Pulmonar/microbiologia
12.
Eur J Immunol ; 47(9): 1414-1426, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28744851

RESUMO

The innate immune system initiates immune responses by pattern-recognition receptors (PRR). Virus-derived nucleic acids are sensed by the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) family and the toll-like receptor (TLR) family as well as the DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS). These receptors activate IRF3/7 and NF-κB signaling pathways to induce the expression of type I interferons (IFNs) and other cytokines firing antiviral responses within the cell. However, to achieve a favorable outcome for the host, a balanced production of IFNs and activation of antiviral responses is required. Post-translational modifications (PTMs), such as the covalent linkage of functional groups to amino acid chains, are crucial for this immune homeostasis in antiviral responses. Canonical PTMs including phosphorylation and ubiquitination have been extensively studied and other PTMs such as methylation, acetylation, SUMOylation, ADP-ribosylation and glutamylation are being increasingly implicated in antiviral innate immunity. Here we summarize our recent understanding of the most important PTMs regulating the antiviral innate immune response, and their role in virus-related immune pathogenesis.


Assuntos
DNA Viral/imunologia , Imunidade Inata , Processamento de Proteína Pós-Traducional , RNA Viral/imunologia , Viroses/imunologia , Animais , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , NF-kappa B/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais , Receptores Toll-Like/metabolismo
13.
Nano Lett ; 17(8): 5119-5125, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28737928

RESUMO

With the rapid development of nanoscale structuring technology, the precision in the etching reaches the sub-10 nm scale today. However, with the ongoing development of nanofabrication the etching mechanisms with atomic precision still have to be understood in detail and improved. Here we observe, atom by atom, how preferential facets form in CaO crystals that are etched by an electron beam in an in situ high-resolution transmission electron microscope (HRTEM). An etching mechanism under electron beam irradiation is observed that is surprisingly similar to chemical etching and results in the formation of nanofacets. The observations also explain the dynamics of surface roughening. Our findings show how electron beam etching technology can be developed to ultimately realize tailoring of the facets of various crystalline materials with atomic precision.

14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(6): 865-870, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-32677394

RESUMO

OBJECTIVE: To determine the regulatory and molecular mechanism of lncRNA MALAT1 in response to sepsis induced by lipopolysaccharide (LPS) in rats. METHODS: The expressions of lncRNA MALAT1 and miR-146a in U937 cells and peripheral blood samples of the rats with and without LPS-induced sepsis were detected using quantitative real-time reverse transcription PCR (qRT-PCR). The relationship between lncRNA MALAT1 and miR-146a was affirmed through luciferase assay. The expressions of p-P65, P65, TNF-α and iNOS were tested by Western blot. The expressions of TNF-α and iNOS in the lung tissues of the rats were measured by immunohistochemistry. RESULTS: The rats with LPS-induced sepsis had higher expressions of lncRNA MALAT1 in U937 cells than those without sepsis (P<0.001). In comparison with scramble, si-MALAT1 attenuated the expression of lncRNA MALAT1 and increased the expression of miR-146a (P<0.001). MiR-146a was the target of lncRNA MALAT1. si-MALAT1 decreased the p-P65/P65 ratio and and the expressions of TNF-α and iNOS in the rats with LPS-induced sepsis. In contrast, miR-146a inhibitor increased p-P65/P65 ratio and the expressions of TNF-α and iNOS in the rats with LPS-induced septis (P<0.001). Co-transfection with si-MALAT1 attenuated the elevated level of p-P65/P65 ratio and expressions of TNF-α and iNOS resulting from miR-146a inhibitor (P<0.001). LPS and scramble decreased the expression of miR-146a and increased the p-P65/P65 ratio compared with the healthy controls (P<0.01). Compared with scramble, si-MALAT1 increased the expression of miR-146a and attenuated the p-P65/P65 ratio (P<0.01). Higher numbers of TNF-α and iNOS positive cells were found in those with LPS-induced sepsis and those with scramble interventions (P<0.001). Compared with scramble, si-MALAT1 reduced the number of TNF-α and iNOS positive cells (P<0.01). CONCLUSIONS: LncRNA MALAT1 modulates the immunoreaction of rats with LPS -induced sepsis by targeting miR-146a/NF-κB P65.

15.
Infect Immun ; 85(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28652310

RESUMO

Exoenzyme Y (ExoY) is a type III secretion system effector found in 90% of the Pseudomonas aeruginosa isolates. Although it is known that ExoY is a soluble nucleotidyl cyclase that increases the cytoplasmic levels of nucleoside 3',5'-cyclic monophosphates (cNMPs) to mediate endothelial Tau phosphorylation and permeability, its functional role in the innate immune response is still poorly understood. Transforming growth factor ß-activated kinase 1 (TAK1) is critical for mediating Toll-like receptor (TLR) signaling and subsequent activation of NF-κB and AP-1, which are transcriptional activators of innate immunity. Here, we report that ExoY inhibits proinflammatory cytokine production through suppressing the activation of TAK1 as well as downstream NF-κB and mitogen-activated protein (MAP) kinases. Mice infected with ExoY-deficient P. aeruginosa had higher levels of tumor necrosis factor (TNF) and interleukin-6 (IL-6), more neutrophil recruitment, and a lower bacterial load in lung tissue than mice infected with wild-type P. aeruginosa Taken together, our findings identify a previously unknown mechanism by which P. aeruginosa ExoY inhibits the host innate immune response.


Assuntos
Proteínas de Bactérias/metabolismo , Glucosiltransferases/metabolismo , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Imunidade Inata , MAP Quinase Quinase Quinases/antagonistas & inibidores , Fósforo-Oxigênio Liases/metabolismo , Pseudomonas aeruginosa/patogenicidade , Animais , Proteínas de Bactérias/genética , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Deleção de Genes , Glucosiltransferases/genética , Humanos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fósforo-Oxigênio Liases/genética , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/enzimologia , Fator de Transcrição AP-1/metabolismo
16.
Small ; 13(27)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28556596

RESUMO

The surface energy and surface stability of Ag nanocrystals (NCs) are under debate because the measurable values of the surface energy are very inconsistent, and the indices of the observed thermally stable surfaces are apparently in conflict. To clarify this issue, a transmission electron microscope is used to investigate these problems in situ with elaborately designed carbon-shell-capsulated Ag NCs. It is demonstrated that the {111} surfaces are still thermally stable at elevated temperatures, and the victory of the formation of {110} surfaces over {111} surfaces on the Ag NCs during sublimation is due to the special crystal geometry. It is found that the Ag NCs behave as quasiliquids during sublimation, and the cubic NCs represent a featured shape evolution, which is codetermined by both the wetting equilibrium at the Ag-C interface and the relaxation of the system surface energy. Small Ag NCs (≈10 nm) no longer maintain the wetting equilibrium observed in larger Ag NCs, and the crystal orientations of ultrafine Ag NCs (≈6 nm) can rotate to achieve further shape relaxation. Using sublimation kinetics, the mean surface energy of Ag NCs at 1073 K is calculated to be 1.1-1.3 J m-2 .

17.
Electrophoresis ; 38(5): 572-579, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27557612

RESUMO

Electroosmotic flow is the transport method of choice in microfluidic devices over traditional pressure-driven flow. To date, however, studies on electroosmotic flow have been almost entirely limited to inside microchannels. This work presents the first experimental study of Joule heating effects on electroosmotic fluid entry from the inlet reservoir (i.e., the well that supplies fluids and samples) to the microchannel in a polymer-based microfluidic chip. Electrothermal fluid circulations are observed at the reservoir-microchannel junction, which grow in size and strength with the increasing alternating current to direct current voltage ratio. Moreover, a 2D depth-averaged numerical model is developed to understand the effects of Joule heating on fluid temperature and flow fields in electrokinetic microfluidic chips. This model overcomes the problems encountered in previous unrealistic 2D and costly 3D models, and is able to predict the observed electroosmotic entry flow patterns with a good agreement.


Assuntos
Eletro-Osmose , Temperatura Alta , Simulação por Computador , Modelos Teóricos
18.
Nat Commun ; 15(1): 3913, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724558

RESUMO

Checkerboard lattices-where the resulting structure is open, porous, and highly symmetric-are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g., protein, DNA). Here we show the assembly of checkerboard lattices from colloidal nanocrystals that harness the effects of multiple, coupled physical forces at disparate length scales (interfacial, interparticle, and intermolecular) and that do not rely on chemical binding. Colloidal Ag nanocubes were bi-functionalized with mixtures of hydrophilic and hydrophobic surface ligands and subsequently assembled at an air-water interface. Using feedback between molecular dynamics simulations and interfacial assembly experiments, we achieve a periodic checkerboard mesostructure that represents a tiny fraction of the phase space associated with the polymer-grafted nanocrystals used in these experiments. In a broader context, this work expands our knowledge of non-specific nanocrystal interactions and presents a computation-guided strategy for designing self-assembling materials.

19.
Front Pediatr ; 11: 1088234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937970

RESUMO

Objective: The objectives of this study was to review the clinical features and surgical treatment outcomes of congenital second branchial cleft anomalies (CSBCAs) and to investigate the characteristic computed tomography (CT) findings of CSBCAs. Methods: We conducted a retrospective study of 52 children who were referred to Shanghai Children's Hospital from October 2014 to December 2021 diagnosed as CSBCAs. Results: There were 36 males and 16 females. Of them, 35 patients were presented as having a skin pit at birth or discharge from the skin opening on the lateral neck, and 17 patients presented with an asymptomatic or painful mass. The typical CT features of CSBCAs included isolated and homogeneously hypodense cystic lesions surrounded by a uniformly thin, smooth wall. CSBCAs were generally located at the anteromedial border of the sternocleidomastoid muscle, posterior to the submandibular gland, and lateral to the carotid sheath. All patients were treated surgically and only one case underwent ipsilateral tonsillectomy. After a median follow-up of 30 (range 4-90) months, no recurrence or complications were observed. Conclusions: The CSBCAs show some characteristic CT findings, which can help clinicians diagnose and plan surgical strategies. High ligation of the lesions is sufficient for complete excision of CSBCAs.

20.
Nat Commun ; 13(1): 7976, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581611

RESUMO

Binary nanoparticle (NP) superlattices exhibit distinct collective plasmonic, magnetic, optical, and electronic properties. Here, we computationally demonstrate how fluid-fluid interfaces could be used to self-assemble binary systems of NPs into 2D superlattices when the NP species exhibit different miscibility with the fluids forming the interface. We develop a basin-hopping Monte Carlo (BHMC) algorithm tailored for interface-trapped structures to rapidly determine the ground-state configuration of NPs, allowing us to explore the repertoire of binary NP architectures formed at the interface. By varying the NP size ratio, interparticle interaction strength, and difference in NP miscibility with the two fluids, we demonstrate the assembly of an array of exquisite 2D periodic architectures, including AB-, AB2-, and AB3-type monolayer superlattices as well as AB-, AB2-, A3B5-, and A4B6-type bilayer superlattices. Our results suggest that the interfacial assembly approach could be a versatile platform for fabricating 2D colloidal superlattices with tunable structure and properties.

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