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1.
Oxid Med Cell Longev ; 2020: 8096847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908639

RESUMO

Acetaminophen (APAP) toxicity is the leading cause of drug-induced liver failure, which is closely related to mitochondrial dysfunction and oxidative damage. Studies in clinical trials and in animal models have shown that omega-3 polyunsaturated fatty acids (n-3 PUFAs) affect the progression of various types of liver damage. Interestingly, the sex-dependent effect of n-3 PUFAs on human health has also been well documented. However, it is unknown whether supplementation of n-3 PUFAs modulates the pathogenesis of APAP-induced liver failure with sex-specificity. Our results showed that both endogenous and exogenous n-3 PUFAs significantly aggravated the APAP-induced liver injury in male mice, whereas the opposite effects were observed in females. In vivo and in vitro studies demonstrated that estrogen contributes to the gender difference in the regulation of n-3 PUFAs on APAP overdose. We found that n-3 PUFA-mediated regulation of hepatic oxidative stress response and autophagy upon APAP challenge is distinct between male and female mice. Moreover, we provided evidence that ß-catenin signaling activation is responsible for the sex-dependent regulation of APAP hepatotoxicity by n-3 PUFAs. Together, these findings indicated that supplementation with n-3 PUFAs displays sex-differential effect on APAP hepatotoxicity and could have profound significance in the clinical management for drug-induced liver injury.

2.
Environ Sci Pollut Res Int ; 27(35): 44306-44313, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32767009

RESUMO

Anabaena flos-aquae, a typical species of cyanobacterial bloom, was employed as a useful biosorbent for uranium removal. Batch experiments were conducted to examine the effects of different parameters on the uranium uptake amount of Anabaena flos-aquae. The maximum adsorption capacity of 196.4 mg/g was obtained under the optimized experimental conditions. The calculations of kinetic and thermodynamic results proved the adsorption process was endothermic, chemisorption, and spontaneous. The adsorption of uranium onto Anabaena flos-aquae was better defined by the Langmuir model, which indicated the process was a monolayer sorption. In addition, the characterization of the biosorbent before and after uranium sorption implied that the dominant functional groups participated in the uranium adsorption process were hydroxyl, amino, and carboxyl. In conclusion, the environmentally friendly and biocompatible characteristics of Anabaena flos-aquae suggest that it can be a promising biosorbent for uranium removal.


Assuntos
Anabaena flos-aquae , Cianobactérias , Urânio , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
3.
Ann Transl Med ; 8(4): 49, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32175343

RESUMO

Background: Intrauterine adhesion (IUA) prevalence is difficult to measure, but appears to have increased over the last few decades. The reproductive outcomes following hysteroscopic adhesiolysis (HA) for moderate-severe IUAs were unsatisfactory, and few studies have analyzed the clinical characteristics pre-, intra- and post-HA to determine the main risk factors for infertility in patients with IUAs. Methods: This retrospective observational study included 406 patients, desiring fertility, who had undergone HA between January 1st, 2016 to May 31st, 2017, and had moderate-to-severe IUA [5-12 on the American Fertility Society (AFS) classification scale]. Logistic regression was performed to analyze the data of the clinical characteristics associated with IUA. Results: A total of 406 IUA patients were initially collected. Twenty-six [26] were lost during follow-up or excluded by other criteria; 380 were included in the study with a follow-up period ranging from 2 to 3 years. There were 215 patients (56.6%) that became pregnant, of whom 18 spontaneously miscarried, 5 birthed prematurely (31-36 gestational weeks), 182 delivered at term, and 10 were pregnant at the end of the study. A bivariate and binary logistic regression analysis showed that an age of >30 years, cohesive IUA, lack of increased menstrual volume, and more than 2 times undergoing HA procedure were the risk factors for infertility in IUA patients (P<0.05). Conclusions: Age, severity of IUA, increased menstrual volume, and HA procedures were the dominant factors affecting reproductive outcomes and may be regarded as potential predictors for evaluating IUA prognosis.

4.
FEBS J ; 287(2): 310-324, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31386800

RESUMO

The battle between hepatitis B virus (HBV) infection and the host immune defense determines the outcome of the disease. Scavenger receptor A (SRA) is a phagocytic pattern recognition receptor involved in various cellular processes, including lipid metabolism, recognition, and clearance of pathogens or modified self-molecules. Emerging evidence pointed out that SRA might act as an immunomodulator that contributes to innate immune defense against invading pathogens. Herein, we examined the role of SRA in the initiation of type I interferon (IFN) response to HBV infection and the virus clearance. Our results showed that SRA-deficient (SRA-/- ) mice were resistant to HBV infection developed by hydrodynamic injection of HBV replicon plasmid. We found lower levels of HBV DNA and viral protein expression in SRA-/- mice, which was associated with enhanced type I IFN production, compared with wild-type controls. Besides, we performed gain and loss of function experiments and determined that SRA inhibits innate antiviral immune responses to HBV. SRA could interact directly with tumor necrosis factor receptor-associated factor 3 (TRAF3) and inhibit its K63-linked ubiquitination. Moreover, we provided evidence that SRA negatively regulates the stability of TRAF3 protein by promoting the recruitment of OTUB1 to TRAF3. Our findings indicate that SRA plays a crucial role in innate immune signaling by targeting TRAF3 for degradation and balancing the innate antiviral immunity.


Assuntos
Cisteína Endopeptidases/metabolismo , Hepatite B/imunologia , Interferons/metabolismo , Receptores Depuradores Classe A/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Animais , Mutação com Ganho de Função , Células Hep G2 , Hepatite B/virologia , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/fisiologia , Humanos , Imunidade Inata , Mutação com Perda de Função , Camundongos , Camundongos Endogâmicos C57BL , Receptores Depuradores Classe A/genética , Ubiquitinação
5.
Sci Adv ; 5(8): eaaw3415, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31497642

RESUMO

Topological surface states (TSSs) in a topological insulator are expected to be able to produce a spin-orbit torque that can switch a neighboring ferromagnet. This effect may be absent if the ferromagnet is conductive because it can completely suppress the TSSs, but it should be present if the ferromagnet is insulating. This study reports TSS-induced switching in a bilayer consisting of a topological insulator Bi2Se3 and an insulating ferromagnet BaFe12O19. A charge current in Bi2Se3 can switch the magnetization in BaFe12O19 up and down. When the magnetization is switched by a field, a current in Bi2Se3 can reduce the switching field by ~4000 Oe. The switching efficiency at 3 K is 300 times higher than at room temperature; it is ~30 times higher than in Pt/BaFe12O19. These strong effects originate from the presence of more pronounced TSSs at low temperatures due to enhanced surface conductivity and reduced bulk conductivity.

6.
ACS Appl Mater Interfaces ; 11(30): 26863-26871, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31310093

RESUMO

With promising activity and stability for the oxygen reduction reaction (ORR), transition metal nitrides are an interesting class of non-platinum group catalysts for polymer electrolyte membrane fuel cells. Here, we report an active thin-film nickel nitride catalyst synthesized through a reactive sputtering method. In rotating disk electrode testing in a 0.1 M HClO4 electrolyte, the crystalline nickel nitride film achieved high activity and selectivity to four-electron ORR. It also exhibited good stability during 10 and 40 h chronoamperometry measurements in acid and alkaline electrolyte, respectively. A combined experiment-theory approach, with detailed ex situ materials characterization and density functional theory calculations, provides insight into the structure of the catalyst and its surface during catalysis. Design strategies for activity and stability improvement through alloying and nanostructuring are discussed.

7.
Exp Dermatol ; 28(9): 1017-1024, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31260126

RESUMO

Psoriasis is a chronic, relapsing inflammatory skin disorder. Numerous experimental evidence and therapeutic evidence have shown that the innate immune response is critical for the pathogenesis and development of psoriasis. Mannan-binding lectin (MBL), a prototypic pattern recognition molecule of the innate immune system, plays an essential role in the host defense against certain infections and also appears to be a major regulator of inflammation. In this study, we investigated the function of MBL on the course of experimental murine imiquimod (IMQ)-induced psoriasis. Our data showed that MBL-deficient (MBL-/- ) mice exhibited attenuated skin damage characterized by greatly decreased erythema compared with wild-type control mice during the early stages of IMQ-induced psoriasis-like skin inflammation. The reduced skin inflammation in MBL-/- mice was associated with the decreased infiltration of neutrophils. Furthermore, we have determined that MBL deficiency limited the chemokine CXCL1 production from skin keratinocytes upon IMQ stimulation, which might be responsible for the impaired skin recruitment of neutrophils. Additionally, we have provided the data that MBL protein promotes the IMQ-induced expression of CXCL1 and activation of MAPK/NF-κB signalling pathway in human keratinocyte HaCaT cells in vitro. In summary, our study revealed an unexpected role of MBL on keratinocyte function in skin, thus offering a new insight into the pathogenic mechanisms of psoriasis.


Assuntos
Quimiocina CXCL1/biossíntese , Quimiotaxia de Leucócito , Queratinócitos/metabolismo , Lectina de Ligação a Manose/fisiologia , Neutrófilos/fisiologia , Psoríase/imunologia , Animais , Linhagem Celular Transformada , Quimiocina CXCL1/genética , Derme/imunologia , Derme/patologia , Feminino , Humanos , Imiquimode/toxicidade , Inflamação , Queratinócitos/efeitos dos fármacos , Lectina de Ligação a Manose/deficiência , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/imunologia , Lectina de Ligação a Manose/farmacologia , Erros Inatos do Metabolismo/complicações , Erros Inatos do Metabolismo/imunologia , Camundongos , Camundongos Knockout , Psoríase/induzido quimicamente , Psoríase/metabolismo , Organismos Livres de Patógenos Específicos , Regulação para Cima
8.
Front Immunol ; 10: 1239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214191

RESUMO

Mannan-binding lectin (MBL) is a vital element in the host innate immune system, which is primarily produced by the liver and secreted into the circulation. Low serum level of MBL is reported to be associated with an increased risk of arthritis. However, the underlying mechanism by which MBL contributes to the pathogenesis of arthritis is poorly understood. In this study, we investigated the precise role of MBL on the course of experimental murine adjuvant-induced arthritis (AIA). MBL-deficient (MBL-/-) AIA mice showed significantly increased inflammatory responses compared with wild-type C57BL/6 AIA mice, including exacerbated cartilage damage, enhanced histopathological features and high level of tartrate-resistant acid phosphatase (TRAP)-positive cells. MBL protein markedly inhibited the osteoclast formation from human blood monocytes induced by receptor activator of nuclear factor-κB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) in vitro. Mechanistic studies established that MBL inhibited osteoclast differentiation via down-regulation of p38 signaling pathway and subsequent nuclear translocation of c-fos as well as activation of nuclear factor of activated T-cells c1 (NFATc1) pathway. Importantly, we have provided the evidence that concentrations of MBL correlated negatively with the serum levels of amino-terminal propeptide of type I procollagen (PINP) and C-terminal telopeptide of type I collagen (ß-CTX), serum markers of bone turnover, in patients with arthritis. Our study revealed an unexpected function of MBL in osteoclastogenesis, thus providing new insight into inflammatory arthritis and other bone-related diseases in patients with MBL deficiency.


Assuntos
Artrite/etiologia , Artrite/metabolismo , Lectina de Ligação a Manose/metabolismo , Osteogênese , Animais , Artrite/diagnóstico por imagem , Artrite/patologia , Biomarcadores , Reabsorção Óssea/genética , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Sistema de Sinalização das MAP Quinases , Lectina de Ligação a Manose/genética , Camundongos , Monócitos/imunologia , Monócitos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Microtomografia por Raio-X
9.
Oncoimmunology ; 8(2): e1527650, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713782

RESUMO

Mannan binding lectin (MBL), initially known to activate the complement lectin pathway and defend against infection, was recently shown to be potentially involved in the development of several types of cancer; however, its exact role in cancers, especially its effect on tumor microenvironment remain largely unknown. Here, using a murine hepatocellular carcinoma (HCC) model, we showed that MBL was a component of liver microenvironment and MBL-deficient (MBL-/-) mice exhibited an enhanced tumor growth compared with wild-type (WT) mice. This phenomenon was associated with elevation of myeloid derived suppressed cells (MDSCs) in tumor tissue of MBL-/- mice. MBL deficiency also resulted in an increase of activated hepatic stellate cells (HSCs), which showed enhanced cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) production. Pharmacological inhibition of COX-2 in vivo partially abrogated the MBL deficiency-promoted tumor growth and MDSC accumulation. Mechanistic studies revealed that MBL could interact directly with HSCs and inhibit HCC-induced HSCs activation via downregulating the extracellular signal-regulated kinase (ERK)/COX-2/PGE2 signaling pathway. Furthermore, MBL-mediated suppression of HCC is validated by administration of MBL-expressing, liver-specific adeno-associated virus (AAV), which significantly inhibited HCC progression in MBL-/- mice. Taken together, these data reveal that MBL may impact on tumor development by shaping the tumor microenvironment via its interaction with the local stromal cells, and also suggests its potential therapeutic use for the treatment of HCC.

10.
Eur J Immunol ; 49(4): 564-575, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30706943

RESUMO

Mannan-binding lectin (MBL) acts as a soluble pattern recognition molecule in the innate immune system, which is primarily produced by the liver. MBL deficiency occurs with high frequency in the population and is reported to be associated with susceptibility to several liver diseases. In the present study, we investigated the pathophysiological role of MBL in acetaminophen (APAP)-induced hepatotoxicity. After APAP treatment, MBL-deficient (MBL-/- ) mice had significantly higher mortality and aggravated hepatic necrosis as well as elevated serum lactate dehydrogenase and alanine aminotransferase levels compared to control mice. The enhanced hepatotoxicity in MBL-/- mice was associated with increased concentration of APAP toxic metabolisms. Furthermore, we demonstrated here that genetic ablation of MBL resulted in excessive reactive oxygen species (ROS) production and enhanced c-Jun N-terminal kinase (JNK) activation, leading to up-regulated specificity protein 1 (SP1) nuclear expression, thus promoted CYP2E1 hepatic expression and consequently exacerbated APAP-induced liver injury in mice. Importantly, we have validated that MBL protected against APAP toxicity in human HepaRG cells in vitro with the same mechanism. Our study revealed an unexpected function of MBL in drug metabolism, thus providing new insight into the drug-induced liver injury in patients with MBL deficiency.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citocromo P-450 CYP2E1/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lectina de Ligação a Manose/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator de Transcrição Sp1/metabolismo , Animais , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Expressão Gênica , Lectina de Ligação a Manose/deficiência , Camundongos , Camundongos Knockout
11.
J Leukoc Biol ; 105(1): 177-186, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30351498

RESUMO

Noninfectious liver injury, including the effects of drugs and diet, is a major cause of liver diseases worldwide. The innate inflammatory response to hepatocyte death plays a crucial role in the outcome of liver injury. Mannan-binding lectin (MBL) is a pattern recognition molecule of the innate immune system, which is primarily produced by liver. MBL deficiency occurs with high frequency in the population and is reported associated with predisposition to infectious diseases. We here observed that genetic MBL ablation strongly sensitizes mice to sterile liver injury induced by carbon tetrachloride (CCl4 ). Aggravated liver damage was shown in CCl4 -administrated MBL-/- mice, as evidenced by severe hepatocyte death, elevated serum alanine aminotransferase and lactate dehydrogenase activity, and enhanced production of inflammatory cytokines. Mechanistic studies established that MBL deficiency caused increased chemokine CXCL2 production from liver macrophages upon CCl4 stimulation, thereby promoting the hepatic recruitment of neutrophils and subsequent liver damage. Furthermore, MBL-mediated protection from CCl4 -induced liver injury was validated by administration of an MBL-expressing liver-specific adeno-associated virus, which effectively ameliorated the hepatic damage in CCl4-treated MBL-/- mice. We propose that MBL may be exploited as a new therapeutic approach in the treatment of chemical-induced sterile liver injury in patients with MBL deficiency.


Assuntos
Fígado/lesões , Fígado/metabolismo , Lectina de Ligação a Manose/deficiência , Infiltração de Neutrófilos , Animais , Tetracloreto de Carbono , Quimiocina CXCL2/metabolismo , Dependovirus/metabolismo , Fígado/patologia , Macrófagos/metabolismo , Lectina de Ligação a Manose/metabolismo , Camundongos Endogâmicos C57BL
12.
Psychol Rep ; 122(5): 1666-1677, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30080110

RESUMO

Previous studies have pondered the relevance of social networking sites (SNSs) to psychological well-being, but few have taken online affective experience into consideration. To extend previous research on the relationship between SNSs and psychological well-being, we opted to target emotions experienced while visiting SNSs as a means to predict off-line well-being. In our two studies, we surveyed affective experience on SNSs, overall life satisfaction, and general emotional well-being of young adults who access SNSs regularly. The results consistently demonstrated a positive association between SNS affective experience and off-line well-being. This finding held with SNS activities (Studies 1 and 2) and relevant personality traits (i.e., the Big Five factors, self-esteem; Study 2) considered in simultaneity. Our research highlights the important role of affective experience on SNSs in predicting off-line well-being as well as helps clarify the relationship between SNSs and well-being.


Assuntos
Afeto/fisiologia , Redes Sociais Online , Satisfação Pessoal , Personalidade/fisiologia , Autoimagem , Mídias Sociais , Adulto , Pequim , Feminino , Humanos , Masculino , Adulto Jovem
13.
Front Psychol ; 9: 1739, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30283384

RESUMO

Previous evidence suggests that narcissistic people tend to visit social networking sites (SNS) frequently, but the emotions accompanying their engagement on such sites has not been a significant subject of study. Therefore, we examined the relationship between narcissism and the affective experience on SNS in two different samples. To do so, we not only examined narcissism as a whole but also distinguished between adaptive and maladaptive narcissism. Results of the two studies consistently showed that: (1) narcissism as a whole was not correlated with the SNS affective experience; (2) maladaptive narcissism was predictive of a worse affective experience on SNS; and (3) partly due to a positive correlation with self-esteem, adaptive narcissism was associated with a better SNS affective experience. In addition, these findings held with SNS activities considered in simultaneity. The present research extends our understanding of the relationship between narcissism and social networking as well as that between emotion and social networking.

14.
Front Psychol ; 9: 554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867619

RESUMO

Past research has documented various cultural and psychological changes in contemporary China. In two studies, we examine how Chinese people's need for uniqueness (NFU) also has changed. In Study 1, we found a significant cross-generational increase in Chinese participants' self-reported NFU. In Study 2, we sampled the names of Chinese newborn babies over the last five decades and found that parents have been increasingly likely to use unique characters to name their children. These findings suggest that the NFU has been rising in China, a historically collectivistic-oriented society. Theoretical and practical implications of our findings were discussed.

15.
J Am Chem Soc ; 140(25): 7851-7859, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29874062

RESUMO

Heteroatom-doped carbons have drawn increasing research interest as catalysts for various electrochemical reactions due to their unique electronic and surface structures. In particular, co-doping of carbon with boron and nitrogen has been shown to provide significant catalytic activity for oxygen reduction reaction (ORR). However, limited experimental work has been done to systematically study these materials, and much remains to be understood about the nature of the active site(s), particularly with regards to the factors underlying the activity enhancements of these boron-carbon-nitrogen (BCN) materials. Herein, we prepare several BCN materials experimentally with a facile and controlled synthesis method, and systematically study their electrochemical performance. We demonstrate the existence of h-BN domains embedded in the graphitic structures of these materials using X-ray spectroscopy. These synthesized structures yield higher activity and selectivity toward the 2e- ORR to H2O2 than structures with individual B or N doping. We further employ density functional theory calculations to understand the role of a variety of h-BN domains within the carbon lattice for the ORR and find that the interface between h-BN domains and graphene exhibits unique catalytic behavior that can preferentially drive the production of H2O2. To the best of our knowledge, this is the first example of h-BN domains in carbon identified as a novel system for the electrochemical production of H2O2.

16.
Exp Dermatol ; 27(9): 1015-1022, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29851146

RESUMO

Atopic dermatitis (AD) is a common chronic inflammatory skin disease that is often associated with skin barrier dysfunction leading to a higher frequency of bacterial and viral skin infections. Toll-like receptor (TLR) 4 on resident skin cells was involved in sensing pathogens and eliciting pathogen-specific innate and adaptive immune responses. Previous studies have demonstrated that TLR4 was linked to AD severity in context of pathogen infection. However, the immune regulatory role of TLR4 in AD remains to be defined. We here investigated the immune regulatory function of TLR4 in AD induced by repeated epicutaneous application of a hapten, 2,4-dinitrochlorobenzene (DNCB). Our results showed that TLR4-deficient (TLR4-/- ) mice exhibited more severe AD symptoms than WT mice after DNCB challenge. The DNCB-treated TLR4-/- mice also displayed higher expression levels of inflammatory cytokines and stronger Th2 response than WT counterparts. Moreover, the skin expression of thymic stromal lymphopoietin (TSLP), an important potential contributor to allergic inflammation, was significantly elevated in TLR4-/- mice compared with that in WT mice upon DNCB administration. Furthermore, we demonstrated that the migration of langerin-positive dendritic cells (DCs) into draining lymph nodes was enhanced in TLR4-/- mice following DNCB challenge, which is partially dependent on the production of pro-inflammatory cytokine TNF-α. Together, these results determined that TLR4 affected the hapten-induced skin inflammation in the absence of exogenous pathogen infection, suggesting that TLR4 not only regulates infection but also may serve as a modulator of the immune response during AD development.


Assuntos
Movimento Celular , Citocinas/genética , Células Dendríticas/fisiologia , Dermatite Atópica/imunologia , Dermatite Atópica/metabolismo , Receptor 4 Toll-Like/imunologia , Animais , Antígenos de Superfície/metabolismo , Citocinas/metabolismo , Células Dendríticas/metabolismo , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/patologia , Dinitroclorobenzeno , Modelos Animais de Doenças , Eosinófilos/imunologia , Feminino , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Mastócitos/imunologia , Camundongos , Camundongos Knockout , RNA Mensageiro/metabolismo , Células Th1/imunologia , Células Th2/imunologia , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
17.
Nano Lett ; 18(1): 546-552, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29236505

RESUMO

A magnetic, metallic inverse opal fabricated by infiltration into a silica nanosphere template assembled from spheres with diameters less than 100 nm is an archetypal example of a "metalattice". In traditional quantum confined structures such as dots, wires, and thin films, the physical dynamics in the free dimensions is typically largely decoupled from the behavior in the confining directions. In a metalattice, the confined and extended degrees of freedom cannot be separated. Modeling predicts that magnetic metalattices should exhibit multiple topologically distinct magnetic phases separated by sharp transitions in their hysteresis curves as their spatial dimensions become comparable to and smaller than the magnetic exchange length, potentially enabling an interesting class of "spin-engineered" magnetic materials. The challenge to synthesizing magnetic inverse opal metalattices from templates assembled from sub-100 nm spheres is in infiltrating the nanoscale, tortuous voids between the nanospheres void-free with a suitable magnetic material. Chemical fluid deposition from supercritical carbon dioxide could be a viable approach to void-free infiltration of magnetic metals in view of the ability of supercritical fluids to penetrate small void spaces. However, we find that conventional chemical fluid deposition of the magnetic late transition metal nickel into sub-100 nm silica sphere templates in conventional macroscale reactors produces a film on top of the template that appears to largely block infiltration. Other deposition approaches also face difficulties in void-free infiltration into such small nanoscale templates or require conducting substrates that may interfere with properties measurements. Here we report that introduction of "spatial confinement" into the chemical fluid reactor allows for fabrication of nearly void-free nickel metalattices by infiltration into templates with sphere sizes from 14 to 100 nm. Magnetic measurements suggest that these nickel metalattices behave as interconnected systems rather than as isolated superparamagnetic systems coupled solely by dipolar interactions.

18.
J Hepatol ; 68(4): 733-743, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29154963

RESUMO

BACKGROUND & AIMS: The macrophage scavenger receptor 1 (Msr1, also called SRA) is a pattern recognition receptor primarily expressed on myeloid cells, which plays an important role in the maintenance of immune homeostasis. Since MSR1 expression was upregulated in the livers of patients with fulminant hepatitis (FH), we investigated the functional mechanism of Msr1 in FH pathogenesis. METHODS: Msr1-deficient (Msr1-/-) mice and their wild-type (WT) littermates were infected with mouse hepatitis virus strain-A59 (MHV-A59) to induce FH, and the levels of tissue damage, serum alanine aminotransferase, inflammatory cytokines and complement component 5a (C5a) were measured and compared. Liver injury was studied after MHV infection with or without neutrophil depletion. RESULTS: Our results showed that Msr1-/- mice were resistant to MHV-induced hepatitis. Treatment with the C5a receptor antagonist (C5aRa) diminished the differences in inflammatory responses and liver injury between MHV-infected wild-type and Msr1-/- mice, suggesting that C5a-induced pro-inflammatory response plays a critical role in the Msr1-mediated regulation of FH pathogenesis. We demonstrated that Msr1 efficiently enhanced transforming growth factor-activated kinase-1 phosphorylation in neutrophils upon MHV-A59 stimulation, thereby promoting the activation of the extracellular signal-regulated kinase pathway and subsequent NETosis formation. Moreover, we provided evidence that blockage of Msr1 attenuated the liver damage caused by MHV-A59 infection. CONCLUSIONS: Msr1 promotes the pathogenesis of virus-induced FH by enhancing induction of neutrophil NETosis and subsequent complement activation. Targeting Msr1 may be employed as a new immunotherapeutic strategy for FH. LAY SUMMARY: Virus-induced fulminant hepatitis (FH) is a disease with a high mortality worldwide. Enhanced levels of macrophage scavenger receptor 1 (Msr1) in the liver of patients with FH and of murine experimental FH indicated Msr1 plays a role in the pathogenesis of FH. Herein, we demonstrate that mice deficient in Msr1 are resistant to FH induced by MHV-A59, and the Msr1 inhibitor fucoidan suppresses the progression of FH in mice. Our study suggests that use of drugs inhibiting MSR1 function could be beneficial to patients with FH.


Assuntos
Ativação do Complemento , Hepatite Viral Animal/etiologia , Neutrófilos/fisiologia , Receptores Depuradores Classe A/fisiologia , Animais , Complemento C5a/biossíntese , Hepatite Viral Animal/imunologia , Hepatite Viral Animal/terapia , Humanos , MAP Quinase Quinase Quinases/fisiologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Vírus da Hepatite Murina , Receptores Depuradores Classe A/antagonistas & inibidores
19.
Acta Biochim Pol ; 64(1): 35-39, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27723845

RESUMO

Numerous evidences suggested that the hepatitis B virus (HBV) was recognized as an important factor in the development of hepatocellular carcinoma (HCC). Dickkopf-1 (DKK1) recently was reported to be involved in the progress of HCC. HBV may regulate DKK1 expression in hematoma carcinogenesis. Here, we demonstrated that HBV could regulate DKK1 promoter activity which resulted in upregulation of its mRNA and protein expression in several HBV existing cell lines, and HBx played a prominent role in this process. Transcription factor binding site search result showed that there is a SP1 site in DKK1 promoter region. Luciferase assay showed that overexpression of SP1 could increase DKK1 promoter activity in a dose dependent manner. Accordingly, siRNA inhibition of SP1 expression reduced DKK1 promoter activity and decreased the expression of DKK1 protein.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Fator de Transcrição Sp1/fisiologia , Transativadores/fisiologia , Sítios de Ligação , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Regiões Promotoras Genéticas , RNA Interferente Pequeno/farmacologia , Fator de Transcrição Sp1/antagonistas & inibidores , Fator de Transcrição Sp1/metabolismo , Proteínas Virais Reguladoras e Acessórias
20.
Q J Exp Psychol (Hove) ; 70(6): 1023-1032, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26444132

RESUMO

Western participants endorse a higher number of positive traits as self-descriptive, but endorse a lower number of negative traits as self-descriptive. They also respond quicker to categorize positive traits as self-descriptive, but respond slower to categorize negative traits as self-descriptive. Is this self-positivity bias qualified by the cultural value of modesty? We induced modesty (vs. punctuality) and assessed self-descriptiveness judgments and response times among Chinese participants. We replicated the self-positivity bias in regards to both self-descriptiveness judgments and response times. In the case of self-descriptiveness judgments, however, the bias was partially qualified by modesty. Relative to control participants, those in the modesty condition endorsed fewer positive traits as self-descriptive and manifested a tendency toward endorsing more negative traits as self-descriptive. In the case of response times, the self-positivity bias was unqualified by modesty. Within both conditions, participants were quicker to categorize positive traits as self-descriptive and were slower to categorize negative traits as self-descriptive. The results speak to the relation between the self-positivity bias and the self-reference effect and illustrate the malleability of self-processing.


Assuntos
Cultura , Julgamento , Autoimagem , Adolescente , Adulto , Análise de Variância , Viés , Feminino , Humanos , Masculino , Tempo de Reação , Adulto Jovem
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