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1.
Immunity ; 53(5): 1108-1122.e5, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33128875

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is a global public health crisis. However, little is known about the pathogenesis and biomarkers of COVID-19. Here, we profiled host responses to COVID-19 by performing plasma proteomics of a cohort of COVID-19 patients, including non-survivors and survivors recovered from mild or severe symptoms, and uncovered numerous COVID-19-associated alterations of plasma proteins. We developed a machine-learning-based pipeline to identify 11 proteins as biomarkers and a set of biomarker combinations, which were validated by an independent cohort and accurately distinguished and predicted COVID-19 outcomes. Some of the biomarkers were further validated by enzyme-linked immunosorbent assay (ELISA) using a larger cohort. These markedly altered proteins, including the biomarkers, mediate pathophysiological pathways, such as immune or inflammatory responses, platelet degranulation and coagulation, and metabolism, that likely contribute to the pathogenesis. Our findings provide valuable knowledge about COVID-19 biomarkers and shed light on the pathogenesis and potential therapeutic targets of COVID-19.


Assuntos
Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Plasma/metabolismo , Pneumonia Viral/sangue , Pneumonia Viral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , COVID-19 , Infecções por Coronavirus/classificação , Infecções por Coronavirus/metabolismo , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Pandemias/classificação , Pneumonia Viral/classificação , Pneumonia Viral/metabolismo , Proteômica , Reprodutibilidade dos Testes , SARS-CoV-2
2.
BMC Cancer ; 24(1): 610, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773439

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a major complication of breast cancer surgical patients. Assessing VTE awareness enables medical staff to tailor educational programs that improve patient self-management and reduce VTE risk. Therefore, this study aimed to assess VTE awareness among breast cancer surgical patients and identify factors influencing their awareness level. METHODS: A multicenter cross-sectional study was conducted on breast cancer patients scheduled for surgery from May 2023 to November 2023. Data were collected using a general information form and a validated self-assessment questionnaire on VTE awareness for breast cancer surgical patients. Univariate analysis and multiple linear regression analysis were used to analyze the data. RESULTS: Of 1969 patients included, the term awareness rates for deep vein thrombosis and pulmonary embolism were 42.5% and 26.1%, respectively. Information about VTE was primarily obtained from doctors (30.4%), nurses (24.0%), and social media (23.3%). The overall average VTE awareness score was 1.55 ± 0.53, with the dimension of VTE preventive measures scoring highest, and VTE clinical symptoms/signs scoring lowest. Multivariate analysis identified education level, personal VTE history, chemotherapy and surgical history, and the hospital's regional location as significant factors associated with VTE awareness level (p < 0.05). CONCLUSION: This study highlights a critical need for improved VTE awareness among breast cancer surgical patients, particularly regarding clinical symptoms/signs. Health education programs are recommended especially tailored for patients with lower education levels, no history of VTE, or without prior surgery or chemotherapy, to improve their understanding of VTE.


Assuntos
Neoplasias da Mama , Conhecimentos, Atitudes e Prática em Saúde , Tromboembolia Venosa , Humanos , Feminino , Estudos Transversais , Neoplasias da Mama/cirurgia , Neoplasias da Mama/complicações , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/epidemiologia , Pessoa de Meia-Idade , Adulto , Fatores de Risco , Inquéritos e Questionários , Idoso , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle
3.
Langmuir ; 40(18): 9439-9448, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38656152

RESUMO

To improve the tribological properties of porous polyimide (PPI), ZDDP-mixed PAO4 was impregnated in PPI (denoted as ZPPI), and the tribological properties of ZPPI under single- and double-contacts were investigated. In the single-contact of ZPPI-steel, a rough and thick tribofilm was formed on the steel ball, which could protect the steel surface but resulted in large fluctuations in the friction coefficient. In the double-contact of ZPPI-steel-steel, ZDDP formed a uniform and thinner tribofilm on steel surfaces, leading to a lower friction. ZDDP could inhibit the formation of iron oxides significantly in the double-contact, while the antioxidant effect of ZDDP in the single-contact of ZPPI-steel was not obvious. ZnS and ZnO generated from ZDDP were adsorbed in the ZPPI pores, which aggravated the blackening of the ZPPI worn surface.

4.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000299

RESUMO

In the rosid species Arabidopsis thaliana, the AP2-type AP2 transcription factor (TF) is required for specifying the sepals and petals identities and confers a major A-function to antagonize the C-function in the outer floral whorls. In the asterid species Petunia, the AP2-type ROB TFs are required for perianth and pistil development, as well as repressing the B-function together with TOE-type TF BEN. In Long-homostyle (LH) Fagopyrum esculentum, VIGS-silencing showed that FaesAP2 is mainly involved in controlling filament and style length, but FaesTOE is mainly involved in regulating filament length and pollen grain development. Both FaesAP2 (AP2-type) and FaesTOE (TOE-type) are redundantly involved in style and/or filament length determination instead of perianth development. However, neither FaesAP2 nor FaesTOE could directly repress the B and/or C class genes in common buckwheat. Moreover, the FaesAP1_2 silenced flower showed tepal numbers, and filament length decreased obviously. Interestingly, yeast one-hybrid (Y1H) and dual-luciferase reporter (DR) further suggested that FaesTOE directly up-regulates FaesAP1_2 to be involved in filament length determination in LH common buckwheat. Moreover, the knockdown of FaesTOE expression could result in expression down-regulation of the directly target FaesAP1_2 in the FaesTOE-silenced LH plants. Our findings uncover a stamen development pathway in common buckwheat and offer deeper insight into the functional evolution of AP2 orthologs in the early-diverging core eudicots.


Assuntos
Fagopyrum , Flores , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fagopyrum/genética , Fagopyrum/crescimento & desenvolvimento , Fagopyrum/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/genética
5.
Small ; 19(22): e2300699, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36843312

RESUMO

AgCuSe-based materials have attracted great attentions recently in thermoelectric (TE) field due to their extremely high electron mobility, ultralow lattice thermal conductivity, and abnormal "brittle-ductile" transition at room temperature. However, although the investigation on the crystal structure of AgCuSe low-temperature phase (named as ß-AgCuSe) was started more than half a century before, it is still in controversy yet, which greatly limits the understanding of its intriguing electrical, thermal, and mechanical performance. In this work, via adopting the advanced three-dimensional electron diffraction technique, this study finds that the AgCuSe-based materials crystalize in an incommensurately modulated structure with an orthorhombic Pmmn(0ß1/2)s00 superspace group. The local lattice distortion in the incommensurately modulated structure has weak effects on the conduction band minimum due to the delocalized and isotropic feature of Ag 5s states, leading to high carrier mobility. Likewise, the inhomogeneous, weak, and anisotropic Ag-Se bonds result in the high degree of anharmonicity and ultralow lattice thermal conductivity. Furthermore, alloying S in AgCuSe reinforces the interaction between the adjacent Ag-Se layers, yielding the "brittle-ductile" transition at room temperature. This work well interprets the structure-performance relationship of AgCuSe-based materials and sheds light on the future investigation of this class of promising TE materials.

6.
Environ Sci Technol ; 57(48): 20400-20409, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37987747

RESUMO

Defect engineering can provide a feasible approach to achieving ambient molecular oxygen activation. However, conventional surface defects (e.g., oxygen vacancies, OVs), featured with the coordinatively unsaturated metal sites, often favor the reduction of O2 to •O2- rather than O22- via two-electron transfer, hindering the efficient pollutant removal with high electron utilization. Herein, we demonstrate that this bottleneck can be well discharged by modulating the electronic structure of OVs via phosphorization. As a proof of concept, TiO2 nanoparticles are adopted as a model material for NaH2PO2 (HP) modification, in which HP induces the formation of OVs via weakening the Ti-O bonds through the hydrogen bond interactions. Additionally, the formed Ti-O-P covalent bond refines the electronic structure of OVs, which enables rapid electron transfer for two-electron molecular oxygen activation. As exemplified by NO oxidation, HP-modified TiO2 with abundant OVs achieved complete NO removal with high selectivity for benign nitrate, superior to that of pristine TiO2. This study highlights a promising approach to regulate the O2 activation via an electronic structure modulation and provides fresh insights into the rational design of a photocatalyst for environmental remediation.


Assuntos
Elétrons , Oxigênio , Ligação de Hidrogênio , Oxirredução
7.
Aesthetic Plast Surg ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110739

RESUMO

BACKGROUND: Inverted nipple deformity presents an unsatisfactory appearance that may induce an unpleasant sex life, but can also be associated with psychological discomfort and increased the functional problems, such as local irritation and inflammation. METHODS: Multiple techniques have been used to correct inverted nipples, but they mostly lead to different problems such as deficiency of the nerve or duct, recurrence of the inverted nipple, and hypopigmented scars in the areola. To minimize complications and maintain the stability of the reconstructed nipple, we presented a minimal incision technique that designed four 3-mm-sized horizontal microincisions, which ran a sun-cross through the periphery and the core of the nipple to push the nipple together, then a vertical suture ran longitudinal to close the transverse incision to stabilize the projection. RESULTS: This technique was performed in 71 patients classified as grade II or III of the inverted nipples, comprising 53 congenital cases and 18 patients with acquired deformity. Thirty-four patients had bilateral inverted nipples, and 37 patients had unilateral inverted nipple. During a mean follow-up period of 15 months, 70 corrected nipples remained raised without recurrence, and one nipple was found retracted at the outpatient clinic after 3 months. There were no serious complications associated with surgery regarding nipple necrosis, seven patients got temporary swelling, two patients got infected after touching water, three patients got extravasated blood, eight patients indicated that they touched scar under the nipple, and two patients reflected nipple dysesthesia. In the 15 months follow-up, the patients with Grade II nipple inversion maintained a nipple average height of 9.54 ± 0.95, and the patients with Grade III nipple inversion maintained a nipple average height of 9.19 ± 1.09, and 86.63% of patients were satisfied with their results. CONCLUSION: This is a simple, safe, effective and reliable technique that should be considered, providing sustained results over the long-term follow-up period with a high rate of stable eversion and low incidence of ischemia, necrosis, scarring and dysesthesia. The vertical scar of the transverse incision closure leads to an esthetic appearance without apparent scarring and minimizes the risk of an altered nipple sensation. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

8.
J Environ Sci (China) ; 134: 126-137, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673528

RESUMO

Pyrazinoquinoxaline-based graphdiyne (PQ-GDY) contains a fixed number of sp-sp2 hybridized carbon atoms and pyrazine-like sp2 hybridized N atoms. In this paper, NH2-UIO-66(Zr) on PQ-GDY substrate was successfully constructed with the help of microwave-assisted heating. PQ-GDY surface acts as a microwave antenna under microwave irradiation to rapidly absorb microwave energy and form hot spots (hot spot effect), which facilitates the formation of well-dispersed NH2-UIO-66(Zr) with good crystallinity. Transient absorption spectra show that high hole transport property of PQ-GDY can accelerate the migration of photogenerated holes from NH2-UIO-66(Zr) to PQ-GDY and greatly reduce the recombination rate of photogenerated electrons and holes due to the strong interaction between PQ-GDY and NH2-UIO-66(Zr). Under visible light (λ ≥ 420 nm), PQ-GDY@NH2-UIO-66(Zr) shows high photocatalytic stability and high NOx removal rate up to 74%, which is 44% higher than that of primitive NH2-UIO-66(Zr). At the same time, it inhibits the formation of toxic by-products (NO2) and limits its concentration to a low level.


Assuntos
Micro-Ondas , Ácidos Ftálicos , Luz , Carbono
9.
Zhongguo Zhong Yao Za Zhi ; 48(18): 5024-5031, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37802844

RESUMO

Chemical constituents were isolated and purified from ethyl acetate fraction of Arctium lappa leaves by silica gel, ODS, MCI, and Sephadex LH-20 column chromatography. Their structures were identified with multiple spectroscopical methods including NMR, MS, IR, UV, and X-ray diffraction combined with literature data. Twenty compounds(1-20) were identified and their structures were determined as arctanol(1), citroside A(2), melitensin 15-O-ß-D-glucoside(3), 11ß,13-dihydroonopordopicrin(4), 11ß,13-dihydrosalonitenolide(5), 8α-hydroxy-ß-eudesmol(6), syringin(7), dihydrosyringin(8), 3,4,3',4'-tetrahydroxy-δ-truxinate(9),(+)-pinoresinol(10), phillygenin(11), syringaresinol(12), kaeperferol(13), quercetin(14), luteolin(15), hyperin(16), 4,5-O-dicaffeoylquinic acid(17), 1H-indole-3-carboxaldehyde(18), benzyl-ß-D-glucopyranoside(19), and N-(2'-phenylethyl) isobutyramide(20). Among them, compound 1 is a new norsesquiterpenoid, and compounds 2-5, 7-8, and 18-20 are isolated from this plant for the first time.


Assuntos
Arctium , Arctium/química , Espectroscopia de Ressonância Magnética , Luteolina/análise , Folhas de Planta/química
10.
PLoS Pathog ; 16(4): e1008509, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32302362

RESUMO

Zika virus (ZIKV) is a unique flavivirus with high tropism to the testes. ZIKV can persist in human semen for months and can cause testicular damage in male mice. However, the mechanisms through which ZIKV enters the testes remain unclear. In this study, we revealed that matrix metalloproteinase 9 (MMP9) was upregulated by ZIKV infection in cell culture and in A129 mice. Furthermore, using an in vitro Sertoli cell barrier model and MMP9-/- mice, we found that ZIKV infection directly affected the permeability of the blood-testis barrier (BTB), and knockout or inhibition of MMP9 reduced the effects of ZIKV on the Sertoli cell BTB, highlighting its role in ZIKV-induced disruption of the BTB. Interestingly, the protein levels of MMP9 were elevated by ZIKV nonstructural protein 1 (NS1) in primary mouse Sertoli cells (mSCs) and other cell lines. Moreover, the interaction between NS1 and MMP9 induced the K63-linked polyubiquitination of MMP9, which enhanced the stability of MMP9. The upregulated MMP9 level led to the degradation of essential proteins involved in the maintenance of the BTB, such as tight junction proteins (TJPs) and type Ⅳ collagens. Collectively, we concluded that ZIKV infection promoted the expression of MMP9 which was further stabilized by NS1 induced K63-linked polyubiquitination to affect the TJPs/ type Ⅳ collagen network, thereby disrupting the BTB and facilitating ZIKV entry into the testes.


Assuntos
Barreira Hematotesticular/metabolismo , Barreira Hematotesticular/virologia , Metaloproteinase 9 da Matriz/metabolismo , Testículo/virologia , Infecção por Zika virus/metabolismo , Zika virus/fisiologia , Células A549 , Animais , Barreira Hematotesticular/enzimologia , Colágeno Tipo IV/metabolismo , Células HEK293 , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sêmen/metabolismo , Sêmen/virologia , Células de Sertoli/enzimologia , Células de Sertoli/metabolismo , Células de Sertoli/virologia , Espermatogênese , Testículo/irrigação sanguínea , Testículo/metabolismo , Proteínas de Junções Íntimas/metabolismo , Regulação para Cima , Proteínas não Estruturais Virais/metabolismo , Internalização do Vírus , Infecção por Zika virus/enzimologia , Infecção por Zika virus/virologia
11.
Int J Mol Sci ; 23(22)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36430880

RESUMO

The identification downstream genes of floral organ identity regulators are critical to revealing the molecular mechanisms underlying floral morphogenesis. However, a general regulatory pathway between floral organ identity genes and their downstream targets is still unclear because of the lack of studies in nonmodel species. Here, we screened a direct downstream target gene, FaesELF3, of a stamen identity transcription factor, FaesAP3_1, in long-homostyle (LH) Fagopyrum esculentum moench by using yeast one-hybrid (Y1H) and dual-luciferase reporter (DR) assays. Furthermore, FaesAP3_1-silenced LH plants that produced flowers with part stamens or anthers homeotically converted into a tepaloid structure, and FaesELF3-silenced plants that had flowers with part stamens consisting of a short filament and empty anther (male sterile anther). All these suggested that transcription factor (TF) FaesAP3_1 directly activates FaesELF3 in order to regulate filament elongation and pollen grain development in LH buckwheat. Our data also suggested that other stamen development pathways independent of FaesAP3_1 remain in F. esculentum.


Assuntos
Fagopyrum , Fagopyrum/genética , Pólen/metabolismo , Flores/metabolismo , Genes de Plantas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188736

RESUMO

Hepatitis B virus (HBV) chronically infects approximately 350 million people worldwide, and 600,000 deaths are caused by HBV-related hepatic failure, liver cirrhosis, and hepatocellular carcinoma annually. It is important to reveal the mechanism underlying the regulation of HBV replication. This study demonstrated that osteopetrosis-associated transmembrane protein 1 (Ostm1) plays an inhibitory role in HBV replication. Ostm1 represses the levels of HBeAg and HBsAg proteins, HBV 3.5-kb and 2.4/2.1-kb RNAs, and core-associated DNA in HepG2, Huh7, and NTCP-HepG2 cells. Notably, Ostm1 has no direct effect on the activity of HBV promoters or the transcription of HBV RNAs; instead, Ostm1 binds to HBV RNA to facilitate RNA decay. Detailed studies further demonstrated that Ostm1 binds to and recruits the RNA exosome complex to promote the degradation of HBV RNAs, and knockdown of the RNA exosome component exonuclease 3 (Exosc3) leads to the elimination of Ostm1-mediated repression of HBV replication. Mutant analyses revealed that the N-terminal domain, the transmembrane domain, and the C-terminal domain are responsible for the repression of HBV replication, and the C-terminal domain is required for interaction with the RNA exosome complex. Moreover, Ostm1 production is not regulated by interferon-α (IFN-α) or IFN-γ, and the expression of IFN signaling components is not affected by Ostm1, suggesting that Ostm1 anti-HBV activity is independent of the IFN signaling pathway. In conclusion, this study revealed a distinct mechanism underlying the repression of HBV replication, in which Ostm1 binds to HBV RNA and recruits RNA exosomes to degrade viral RNA, thereby restricting HBV replication.IMPORTANCE Hepatitis B virus (HBV) is a human pathogen infecting the liver to cause a variety of diseases ranging from acute hepatitis to advanced liver diseases, fulminate hepatitis, liver cirrhosis, and hepatocellular carcinoma, thereby causing a major health problem worldwide. In this study, we demonstrated that Ostm1 plays an inhibitory role in HBV protein production, RNA expression, and DNA replication. However, Ostm1 has no effect on the activities of the four HBV promoters; instead, it binds to HBV RNA and recruits RNA exosomes to promote HBV RNA degradation. We further demonstrated that the anti-HBV activity of Ostm1 is independent of the interferon signaling pathway. In conclusion, this study reveals a distinct mechanism underlying the repression of HBV replication and suggests that Ostm1 is a potential therapeutic agent for HBV infection.


Assuntos
Exossomos/metabolismo , Vírus da Hepatite B/fisiologia , Proteínas de Membrana/metabolismo , RNA Viral/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Replicação Viral , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Exossomos/genética , Exossomos/virologia , Técnicas de Silenciamento de Genes , Células HEK293 , Células HeLa , Células Hep G2 , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Humanos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Interferon gama/genética , Interferon gama/metabolismo , Proteínas de Membrana/genética , Domínios Proteicos , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ubiquitina-Proteína Ligases/genética
13.
J Virol ; 93(7)2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30674631

RESUMO

Hepatitis B virus (HBV) infection is the leading cause of chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). This study reveals a distinct mechanism underlying the regulation of HBV replication. HBV activates homeobox A10 (HoxA10) in human hepatocytes, leukocytes, peripheral blood mononuclear cells (PBMCs), HepG2-NTCP cells, leukocytes isolated from CHB patients, and HBV-associated HCC tissues. HoxA10 in turn represses HBV replication in human hepatocytes, HepG2-NTCP cells, and BALB/c mice. Interestingly, we show that during early HBV infection, p38 mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) were activated to facilitate HBV replication; however, during late HBV infection, HoxA10 was induced to attenuate HBV replication. Detailed studies reveal that HoxA10 binds to p38 MAPK, recruits SH2-containing protein tyrosine phosphatase 1 (SHP-1) to facilitate SHP-1 in catalyzing dephosphorylation of p38 MAPK/STAT3, and thereby attenuates p38 MAPK/STAT3 activation and HBV replication. Furthermore, HoxA10 binds to the HBV enhancer element I (EnhI)/X promoter, competes with STAT3 for binding of the promoter, and thereby represses HBV transcription. Taken together, these results show that HoxA10 attenuates HBV replication through repressing the p38 MAPK/STAT3 pathway by two approaches: HoxA10 interacts with p38 MAPK and recruits SHP-1 to repress HBV replication, and HoxA10 binds to the EnhI/X promoter and competes with STAT3 to attenuate HBV transcription. Thus, the function of HoxA10 is similar to the action of interferon (IFN) in terms of inhibition of HBV infection; however, the mechanism of HoxA10-mediated repression of HBV replication is different from the mechanism underlying IFN-induced inhibition of HBV infection.IMPORTANCE Two billion people have been infected with HBV worldwide; about 240 million infected patients developed chronic hepatitis B (CHB), and 650,000 die each year from liver cirrhosis (LC) or hepatocellular carcinoma (HCC). This work elucidates a mechanism underlying the control of HBV replication. HBV infection activates HoxA10, a regulator of cell differentiation and cancer progression, in human cells and patients with CHB and HCC. HoxA10 subsequently inhibits HBV replication in human tissue culture cells and mice. Additionally, HoxA10 interacts with p38 MAPK to repress the activation of p38 MAPK and STAT3 and recruits and facilitates SHP-1 to catalyze the dephosphorylation of p38 MAPK and STAT3. Moreover, HoxA10 competes with STAT3 for binding of the HBV X promoter to repress HBV transcription. Thus, this work reveals a negative regulatory mechanism underlying the control of HBV replication and provides new insights into the development of potential agents to control HBV infection.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT3/metabolismo , Replicação Viral/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Estudos de Casos e Controles , Linhagem Celular , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos/genética , Células Hep G2 , Hepatite B Crônica/virologia , Hepatócitos/metabolismo , Hepatócitos/virologia , Proteínas Homeobox A10 , Humanos , Interferons/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética
14.
FASEB J ; 33(4): 5793-5807, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30653357

RESUMO

Activation of the NACHT, leucine-rich repeat, and pyrin domains-containing protein 3 (collectively known as NLRP3) inflammasome plays a key role in host immune response, which is the first line of defense against cellular stresses and pathogen infections. However, excessive inflammasome activation damages host cells, and therefore it must be precisely controlled. Here, we discover that Cullin1 (CUL1), a key component of the Skp1-Cullin1-F-box E3 ligase, plays a critical role in controlling the NLRP3 inflammasome. CUL1 represses inflammasome assembly in cultured cells, suppresses NLRP3 function in human monocytic cell line macrophages, and attenuates inflammatory responses in mouse model. Detailed studies demonstrate that CUL1 interacts with NLRP3 and promotes NLRP3 ubiquitination, but not protein degradation, to repress the NLRP3 inflammasome activation. Moreover, upon inflammatory stimuli, including ATP and nigericin treatments, CUL1 disassociates from NLRP3 to release the repression of the NLRP3 inflammasome. Thus, this study reveals a distinct and unique mechanism underlying the control of systematic activation of the NLRP3 inflammasome.-Wan, P., Zhang, Q., Liu, W., Jia, Y., Ai, S., Wang, T., Wang, W., Pan, P., Yang, G., Xiang, Q., Huang, S., Yang, Q., Zhang, W., Liu, F., Tan, Q., Zhang, W., Wu, K., Liu, Y., Wu, J. Cullin1 binds and promotes NLRP3 ubiquitination to repress systematic inflammasome activation.


Assuntos
Proteínas Culina/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ubiquitinação/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Feminino , Células HEK293 , Humanos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Nigericina/metabolismo , Proteólise , Células THP-1 , Ubiquitina-Proteína Ligases/metabolismo
15.
Microb Cell Fact ; 19(1): 49, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32103761

RESUMO

BACKGROUND: The GRAS and oleaginous yeast Yarrowia lipolytica (Y. lipolytica) is an attractive cell factory for the production of chemicals and biofuels. The production of many natural products of commercial interest have been investigated in this cell factory by introducing heterologous biosynthetic pathways and by modifying the endogenous pathways. However, since natural products anabolism involves long pathways and complex regulation, re-channelling carbon into the product of target compounds is still a cumbersome work, and often resulting in low production performance. RESULTS: In this work, the carotenogenic genes contained carB and bi-functional carRP from Mucor circinelloides and carotenoid cleavage dioxygenase 1 (CCD1) from Petunia hybrida were introduced to Y. lipolytica and led to the low production of ß-ionone of 3.5 mg/L. To further improve the ß-ionone synthesis, we implemented a modular engineering strategy for the construction and optimization of a biosynthetic pathway for the overproduction of ß-ionone in Y. lipolytica. The strategy involved the enhancement of the cytosolic acetyl-CoA supply and the increase of MVA pathway flux, yielding a ß-ionone titer of 358 mg/L in shake-flask fermentation and approximately 1 g/L (~ 280-fold higher than the baseline strain) in fed-batch fermentation. CONCLUSIONS: An efficient ß-ionone producing GRAS Y. lipolytica platform was constructed by combining integrated overexpressed of heterologous and native genes. A modular engineering strategy involved the optimization pathway and fermentation condition was investigated in the engineered strain and the highest ß-ionone titer reported to date by a cell factory was achieved. This effective strategy can be adapted to enhance the biosynthesis of other terpenoids in Y. lipolytica.


Assuntos
Engenharia Metabólica , Norisoprenoides/metabolismo , Yarrowia/metabolismo , Acetilcoenzima A/metabolismo , Fermentação , Microbiologia Industrial , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Oxigênio/metabolismo , Yarrowia/genética
16.
J Phys Chem A ; 124(47): 9811-9817, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33179907

RESUMO

Tryptophan (Trp) is very necessary for biosystems; therefore, high-efficient detection of Trp is an important subject. Hereof, based on our early research works on fluorescent sensors, we rationally designed and synthesized a fluorescent sensor (SNP5) based on N-(2-aminoethyl)-2-(hexylthio) acetamide-functionalized pillar[5]arene, which showed high selectivity and sensitive recognition for l-Trp (LOD = 2.19 × 10-8 M). Moreover, SNP5 exhibited aggregation-induced emission enhancement fluorescence. Within SNP5, the pillar[5]arene group could act as N-H···π- and C-H···π-interaction sites, as well as a H-bond-interaction site; meanwhile, the N-(2-aminoethyl)-2-(hexylthio) acetamide group also served as a multihydrogen-bonding site. As a result, SNP5 could selectively detect l-Trp through the synergy of the pillar[5]arene group and the N-(2-aminoethyl)-2-(hexylthio) acetamide group. Compared with previous work, the results of this work support the strategy that changing the functionalized group of the pillar[5]arene can adjust the selectivity of the pillar[5]arene-based sensor and achieve the detection of different amino acids. The detection mechanism was specifically researched through experiments and theoretical calculations including frontier orbitals, electrostatic potential, and the independent gradient model approach. Interestingly, these theoretical calculations not only supported the experimental results but also provided a visualized understanding of guest-adaptive multisupramolecular interactions between SNP5 and l-Trp.


Assuntos
Calixarenos/química , Triptofano/análise , Acetamidas/química , Fluorescência , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Estrutura Molecular , Análise Espectral/métodos , Triptofano/química
17.
Soft Matter ; 15(33): 6753-6758, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31397832

RESUMO

In this study, a novel aggregation-induced emission supramolecular organic framework (AIE SOF) with ultrasensitive response, termed FSOF, was constructed using a tri-pillar[5]arene-based foldamer. Interestingly, benefiting from the noise signal shielding properties of FSOF as well as the competition between the cationπ and ππ interactions, the FSOF shows an ultrasensitive response for multi-analytes, such as Fe3+, Hg2+ and Cr3+. The limits of detection (LODs) of the FSOF for Fe3+, Hg2+ and Cr3+ are in the range of 9.40 × 10-10-1.86 × 10-9. More importantly, the xerogel of FSOF exhibits porous mesh structures, which could effect high-efficiency separation above metal ions from their aqueous solution, with adsorption percentages in the range 92.39-99.99%. In addition, by introducing metal ions into the FSOF, a series of metal ions coordinated supramolecular organic frameworks (MSOFs) were successfully constructed. Moreover, MSOFs show selective fluorescence "turn on" ultrasensitive detection CN- (LOD = 2.12 × 10-9) and H2PO4- (LOD = 1.78 × 10-9). This is a novel approach to construct SOFs through a tri-pillar[5]arene-based foldamer, and also provides a new way to achieve ultrasensitive detection and high-efficiency separation.

18.
J Virol ; 91(8)2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28122987

RESUMO

Hepatitis B virus (HBV) infection may cause acute hepatitis B, chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma (HCC). However, the mechanisms by which HBV evades host immunity and maintains chronic infection are largely unknown. Here, we revealed that matrix metalloproteinase 9 (MMP-9) is activated in peripheral blood mononuclear cells (PBMCs) of HBV-infected patients, and HBV stimulates MMP-9 expression in macrophages and PBMCs isolated from healthy individuals. MMP-9 plays important roles in the breakdown of the extracellular matrix and in the facilitation of tumor progression, invasion, metastasis, and angiogenesis. MMP-9 also regulates respiratory syncytial virus (RSV) replication, but the mechanism underlying such regulation is unknown. We further demonstrated that MMP-9 facilitates HBV replication by repressing the interferon (IFN)/Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway, IFN action, STAT1/2 phosphorylation, and IFN-stimulated gene (ISG) expression. Moreover, MMP-9 binds to type I IFN receptor 1 (IFNAR1) and facilitates IFNAR1 phosphorylation, ubiquitination, subcellular distribution, and degradation to interfere with the binding of IFANR1 to IFN-α. Thus, we identified a novel positive-feedback regulation loop between HBV replication and MMP-9 production. On one hand, HBV activates MMP-9 in infected patients and leukocytes. On the other hand, MMP-9 facilitates HBV replication through repressing IFN/JAK/STAT signaling, IFNAR1 function, and IFN-α action. Therefore, HBV may take the advantage of MMP-9 function to establish or maintain chronic infection.IMPORTANCE Hepatitis B virus (HBV) infection may cause chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC). However, the mechanisms by which HBV maintains chronic infection are largely unknown. Matrix metalloproteinase 9 (MMP-9) plays important roles in the facilitation of tumor progression, invasion, metastasis, and angiogenesis. However, the effects of MMP-9 on HBV replication and pathogenesis are not known. This study reveals that MMP-9 expression is activated in patients with CHB, and HBV stimulates MMP-9 production in PBMCs and macrophages. More interestingly, MMP-9 in turn promotes HBV replication through suppressing IFN-α action. Moreover, MMP-9 interacts with type I interferon receptor 1 (IFNAR1) to disturb the binding of IFN-α to IFNAR1 and facilitate the phosphorylation, ubiquitination, subcellular distribution, and degradation of IFNAR1. Therefore, these results discover a novel role of MMP-9 in viral replication and reveal a new mechanism by which HBV evades host immunity to maintain persistent infection.


Assuntos
Vírus da Hepatite B/fisiologia , Interações Hospedeiro-Patógeno , Metaloproteinase 9 da Matriz/metabolismo , Receptor de Interferon alfa e beta/metabolismo , Transdução de Sinais , Replicação Viral , Células Cultivadas , Hepatócitos/virologia , Humanos , Leucócitos Mononucleares/imunologia , Ligação Proteica
19.
Sensors (Basel) ; 18(2)2018 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-29495291

RESUMO

Diverse and varied cyber-attacks challenge the operation of the smart-world system that is supported by Internet-of-Things (IoT) (smart cities, smart grid, smart transportation, etc.) and must be carefully and thoughtfully addressed before widespread adoption of the smart-world system can be fully realized. Although a number of research efforts have been devoted to defending against these threats, a majority of existing schemes focus on the development of a specific defensive strategy to deal with specific, often singular threats. In this paper, we address the issue of coalitional attacks, which can be launched by multiple adversaries cooperatively against the smart-world system such as smart cities. Particularly, we propose a game-theory based model to capture the interaction among multiple adversaries, and quantify the capacity of the defender based on the extended Iterated Public Goods Game (IPGG) model. In the formalized game model, in each round of the attack, a participant can either cooperate by participating in the coalitional attack, or defect by standing aside. In our work, we consider the generic defensive strategy that has a probability to detect the coalitional attack. When the coalitional attack is detected, all participating adversaries are penalized. The expected payoff of each participant is derived through the equalizer strategy that provides participants with competitive benefits. The multiple adversaries with the collusive strategy are also considered. Via a combination of theoretical analysis and experimentation, our results show that no matter which strategies the adversaries choose (random strategy, win-stay-lose-shift strategy, or even the adaptive equalizer strategy), our formalized game model is capable of enabling the defender to greatly reduce the maximum value of the expected average payoff to the adversaries via provisioning sufficient defensive resources, which is reflected by setting a proper penalty factor against the adversaries. In addition, we extend our game model and analyze the extortion strategy, which can enable one participant to obtain more payoff by extorting his/her opponents. The evaluation results show that the defender can combat this strategy by encouraging competition among the adversaries, and significantly suppress the total payoff of the adversaries via setting the proper penalty factor.

20.
Int J Mol Sci ; 19(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072674

RESUMO

Spinal cord injury (SCI) is a severe traumatic lesion of central nervous system (CNS) with only a limited number of restorative therapeutic options. Diosgenin glucoside (DG), a major bioactive ingredient of Trillium tschonoskii Max., possesses neuroprotective effects through its antioxidant and anti-apoptotic functions. In this study, we investigated the therapeutic benefit and underlying mechanisms of DG treatment in SCI. We found that in Sprague-Dawley rats with traumatic SCI, the expressions of autophagy marker Light Chain 3 (LC3) and Beclin1 were decreased with concomitant accumulation of autophagy substrate protein p62 and ubiquitinated proteins, indicating an impaired autophagic activity. DG treatment, however, significantly attenuated p62 expression and upregulated the Rheb/mTOR signaling pathway (evidenced as Ras homolog enriched in brain) due to the downregulation of miR-155-3p. We also observed significantly less tissue injury and edema in the DG-treated group, leading to appreciable functional recovery compared to that of the control group. Overall, the observed neuroprotection afforded by DG treatment warrants further investigation on its therapeutic potential in SCI.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diosgenina/análogos & derivados , Glucosídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Traumatismos da Medula Espinal/prevenção & controle , Animais , Diosgenina/química , Diosgenina/uso terapêutico , Glucosídeos/química , MicroRNAs/genética , Fármacos Neuroprotetores/química , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Trillium/química
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