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1.
Proc Natl Acad Sci U S A ; 120(9): e2219952120, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802416

RESUMO

Social behavior starts with dynamic approach prior to the final consummation. The flexible processes ensure mutual feedback across social brains to transmit signals. However, how the brain responds to the initial social stimuli precisely to elicit timed behaviors remains elusive. Here, by using real-time calcium recording, we identify the abnormalities of EphB2 mutant with autism-associated Q858X mutation in processing long-range approach and accurate activity of prefrontal cortex (dmPFC). The EphB2-dependent dmPFC activation precedes the behavioral onset and is actively associated with subsequent social action with the partner. Furthermore, we find that partner dmPFC activity is responsive coordinately to the approaching WT mouse rather than Q858X mutant mouse, and the social defects caused by the mutation are rescued by synchro-optogenetic activation in dmPFC of paired social partners. These results thus reveal that EphB2 sustains neuronal activation in the dmPFC that is essential for the proactive modulation of social approach to initial social interaction.


Assuntos
Córtex Pré-Frontal , Receptor EphB2 , Comportamento Social , Animais , Camundongos , Encéfalo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Receptor EphB2/genética , Receptor EphB2/fisiologia
2.
J Surg Oncol ; 129(5): 860-868, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38233984

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) has a fibrotic stroma that has both tumor-promoting and tumor-restraining properties. Different types of cancer-associated fibroblasts (CAFs) have been described. Here, we investigated whether CAFs within the same subtype exhibit heterogeneous functions. METHODS: We evaluated the gene and protein expression differences in two myofibroblastic CAF (myCAF) lines using single-cell and bulk RNA-sequencing. We utilized proliferation and migration assays to determine the effect of different CAF lines on a tumor cell line. RESULTS: We found that myCAF lines express an activated stroma subtype gene signature, which is associated with a shorter survival in patients. Although both myCAF lines expressed α-smooth muscle actin (α-SMA), platelet-derived growth factor-α (PDGFR-α), fibroblast-activated protein (FAP), and vimentin, we observed heterogeneity between the two lines. Similarly, despite being consistent with myCAF gene expression overall, heterogeneity within specific genes was observed. We found that these differences extended to the functional level where the two myCAF lines had different effects on the same tumor cell line. The myCAF216 line, which had slightly increased inflammatory CAF-like gene expression and higher protein expression of α-SMA, PDGFR-α, and FAP was found to restrain migration of tumor cells. CONCLUSIONS: We found that two myCAF lines with globally similar expression characteristics had different effects on the same tumor cell line, one promoting and the other restraining migration. Our study highlights that there may be unappreciated heterogeneity within CAF subtypes. Further investigation and attention to specific genes or proteins that may drive this heterogeneity will be important.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Fibroblastos/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral
3.
J Nanobiotechnology ; 22(1): 524, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39217399

RESUMO

Au@Pt nanozyme, a bimetallic core-shell structure Au and Pt nanoparticle, has attracted significant attention due to its excellent catalytic activity and stability. Here, we propose that Au@Pt improves glucose tolerance and reduces TG after four weeks administration. The transcriptomic analysis of mouse liver tissues treated with Au@Pt nanozyme showed changes in genes related to glucose and lipid metabolism signaling pathways, including glycolysis/gluconeogenesis, pyruvate metabolism, PPAR signaling, and insulin signaling. Moreover, analysis of fecal samples from mice treated with Au@Pt nanozyme showed significant changes in the abundance of beneficial gut microbiota such as Dubosiella, Parvibacter, Enterorhabdus, Monoglobus, Lachnospiraceae_UCG-008, Lachnospiraceae_UCG-006, Lachnospiraceae_UCG-001, and Christensenellaceae_R-7_group. Combined multi-omics correlation analyses revealed that the modulation of glucose and lipid metabolism by Au@Pt was strongly correlated with changes in hepatic gene expression profiles as well as changes in gut microbial profiles. Overall, our integrated multi-omics analysis demonstrated that Au@Pt nanozyme could modulate glucose and lipid metabolism by regulating the expression of key genes in the liver and altering the composition of gut microbiota, providing new insights into the potential applications of Au@Pt nanozyme in the treatment of metabolic disorder.


Assuntos
Microbioma Gastrointestinal , Glucose , Ouro , Metabolismo dos Lipídeos , Fígado , Nanopartículas Metálicas , Platina , Animais , Metabolismo dos Lipídeos/efeitos dos fármacos , Ouro/química , Camundongos , Glucose/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Nanopartículas Metálicas/química , Platina/química , Platina/farmacologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Transcriptoma/efeitos dos fármacos , Perfilação da Expressão Gênica , Fezes/microbiologia , Fezes/química , Multiômica
4.
J Nanobiotechnology ; 22(1): 547, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39238027

RESUMO

Rheumatoid arthritis (RA) involves chronic inflammation, oxidative stress, and complex immune cell interactions, leading to joint destruction. Traditional treatments are often limited by off-target effects and systemic toxicity. This study introduces a novel therapeutic approach using hyaluronic acid (HA)-conjugated, redox-responsive polyamino acid nanogels (HA-NG) to deliver tacrolimus (TAC) specifically to inflamed joints. The nanogels' disulfide bonds enable controlled TAC release in response to high intracellular glutathione (GSH) levels in activated macrophages, prevalent in RA-affected tissues. In vitro results demonstrated that HA-NG/TAC significantly reduced TAC toxicity to normal macrophages and showed high biocompatibility. In vivo, HA-NG/TAC accumulated more in inflamed joints compared to non-targeted NG/TAC, enhancing therapeutic efficacy and minimizing side effects. Therapeutic evaluation in collagen-induced arthritis (CIA) mice revealed HA-NG/TAC substantially reduced paw swelling, arthritis scores, synovial inflammation, and bone erosion while suppressing pro-inflammatory cytokine levels. These findings suggest that HA-NG/TAC represents a promising targeted drug delivery system for RA, offering potential for more effective and safer clinical applications.


Assuntos
Artrite Experimental , Artrite Reumatoide , Ácido Hialurônico , Nanogéis , Peptídeos , Tacrolimo , Animais , Ácido Hialurônico/química , Artrite Reumatoide/tratamento farmacológico , Camundongos , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico , Tacrolimo/química , Tacrolimo/farmacocinética , Artrite Experimental/tratamento farmacológico , Peptídeos/química , Peptídeos/farmacologia , Nanogéis/química , Masculino , Células RAW 264.7 , Sistemas de Liberação de Medicamentos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos DBA , Portadores de Fármacos/química , Humanos
5.
Ann Plast Surg ; 93(2): 268-275, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775375

RESUMO

BACKGROUND: As a significant bridge between perforasomes, choke vessels are the key structure of blood supply expansion, also a prerequisite for preventing distal ischemic necrosis of the multiterritory perforator flap, where the remodeling of choke vessels after flap elevation plays an essential role. This systematic review highlights the underlying mechanisms and clinical ways to promote remodeling of choke vessels, as well as experimental observation approaches to further guide researchers. METHODS: A systematic review was conducted from 1975 to 2023 through PubMed, EMBASE, Web of Science, and Cochrane database with the key words "choke vessels" and "perforator flap" to investigate the mechanisms and ways to promote remodeling of choke vessels as well as observation approaches. The inclusion criteria and exclusion criteria were set to screen the literature. RESULTS: A total of 94 literatures were obtained through database retrieval. After removing the duplicate literature, reading the title and abstract, and reviewing the full text finally, 33 articles were included in the final study. CONCLUSIONS: The underlying remodeling of choke vessels may be related to fluid shear stress, hypoxia, and inflammation. The clinical ways to promote remodeling of choke vessels include surgical delay, arterial supercharge, venous superdrainage, drugs, and stem cells. Various experimental methods of observing microvascular morphology allow for a comprehensive research of choke vessels.


Assuntos
Retalho Perfurante , Remodelação Vascular , Humanos , Remodelação Vascular/fisiologia , Retalho Perfurante/irrigação sanguínea , Retalho Perfurante/transplante , Procedimentos de Cirurgia Plástica/métodos
6.
J Environ Manage ; 370: 122390, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243647

RESUMO

The establishment of S-scheme heterojunctions represents an effective strategy for enhancing the transfer and separation of charge carriers, thereby bolstering redox capacities and consequently benefiting subsequent photocatalytic reactions. In this study, the pristine Bi7O9I3 underwent a facile vulcanization process to in-situ produce various composites. Systematical characterizations confirmed the simultaneous generation of Bi7O9I3/Bi2S3 (BI-BS) heterojunctions with surface oxygen vacancies (OVs). Under visible light, these BI-BS composites exhibited improved NO removal efficiencies with reduced NO2 generation compared to bare Bi7O9I3. Particularly, the best candidate BI-BS2 possesses the highest NO removal (43.02%) and lowest NO2 generation (5.44%) among all tested samples. The improvement was primarily attributed to synergetic effects of heterojunction and surface OVs, including enhanced charge separation, heightened light responsiveness, and improved generation of reactive oxygen-containing species through an S-scheme mode. Furthermore, the Density Functional Theory (DFT) calculations had demonstrated that the establishment of BI-BS heterojunctions with surface OVs not only optimized the electronic structure to facilitate the transfer and separation of charge carriers, but also significantly enhanced the adsorption of NO, H2O, and O2 molecules, ultimately favoring the generation of NO3- species. These as-synthesized composites indicated sufficient structural stability and hold potential for the photocatalytic removal of NO at ppb levels.

7.
J Environ Manage ; 360: 121173, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38768523

RESUMO

BACKGROUND: With the rapid escalation of global urbanization, the role of blue-green spaces in urban ecology, public health, and planning has become increasingly prominent. Although their contributions to ecological preservation, public health, and urban design are widely acknowledged, research into public engagement and willingness to participate in the management and planning of these spaces is still in its early stages. OBJECTIVE: This study aims to identify key factors influencing public willingness to participate in blue-green space management, focusing specifically on people's perceptions of blue-green spaces (including perceived quality and accessibility), their usage behaviors (i.e., frequency of usage of blue-green spaces), and their self-assessed physical and mental health. METHODS: We interviewed local residents through random sampling to obtain sample data, and used a representative sample (n = 815, 510 women; 305 men, age 18-85 years, lived in Chengdu for an extensive time) of residents living in Chengdu City, China. Employing a quantitative approach, we examined the relationships between factors such as gender, regular occupation, income, behavior, and health status in relation to the willingness to participate. Additionally, we explored how perceptions and behaviors impacted health statuses and, consequently, inclinations to participate. RESULTS: The findings indicate that individuals with steady occupations and higher incomes are more inclined to engage in the management and planning of blue-green spaces. Notably, men exhibited a greater tendency to participate than women. Furthermore, access to blue-green spaces emerged as a crucial mechanism for addressing health disparities, offering significant implications for urban planning and public health. CONCLUSION: Successful blue-green space planning and understanding of willingness to participate necessitates the holistic consideration of people's perceptions of blue-green spaces, their usage behaviour and their self-rate health. For a tangible impact on health equity and global urban development, it's essential to prioritize blue-green spaces in planning, especially in lower-income regions. This not only promotes environmental perception but can also be a strategic approach to address health disparities. Our findings offer vital insights for tailoring international urban planning and management practices towards these goals.


Assuntos
Saúde Pública , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Adolescente , China , Adulto Jovem , Idoso de 80 Anos ou mais , Urbanização , Cidades , Participação da Comunidade , Planejamento de Cidades
8.
Langmuir ; 39(39): 14173-14188, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37734066

RESUMO

Green biosurfactants are emerging as a promising area of research. However, there is a limited focus on the adsorption and wetting characteristics of biosurfactants on coal dust. This study explores the effects of sophorolipid (SL) biosurfactants on the microstructure and wettability of different coalification degree coal. The microstructure parameters of SL adsorbed on coal dust were measured using a surface tensiometer, contact angle analyzer, and particle size analyzer. The results indicate that SL has the lowest critical surface tension, leading to a 9.25° decrease in the contact angle for low-rank bituminous coal (YZ-LRBC). Furthermore, SL significantly altered the particle size distribution of lignite (NM-LC) and YZ-LRBC. The pore size structure of SL-infiltrated coal dust was quantified using a specific surface area analyzer, revealing a decrease in the specific surface area and an increase in the average pore size. The infrared analysis demonstrated that SL permeation significantly increased the percentage of hydrophilic functional groups (hydroxyl structures) while reducing the hydrophobic functional groups (aliphatic hydrocarbon and aromatic structure). Based on the measured microstructure parameters, a regression equation for contact angle was established: [contact angle (°)] = 73.800 - 0.860 × [D10 (nm)] + 4.280 × [specific surface area (m2/g)]. Notably, the characteristic particle size D10 had a significant negative effect on the contact angle, while the specific surface area had a significant positive effect. These findings provide a theoretical foundation for the application of biosurfactants in water injection to reduce dust and improve the wetting efficiency.

9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 374-379, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-36949701

RESUMO

Objective: To study the current status of non-suicidal self-injury (NSSI) incidents among middle school students in Chengdu during the COVID-19 epidemic and to explore the mechanism of action of depression on the relationship between family environment and NSSI. Methods: Data were obtained from the Chengdu Positive Child Development (CDPD) cohort. In June and July 2020, after primary and secondary schools were reopened after the closure due to the COVID-19 epidemic, on-site questionnaire surveys were conducted with the Deliberate Self-Harm Inventory (DSHI), the Chinese Family Assessment Instrument (C-FAI), and Center for Epidemiologic Studies Depression Scale for Children (CES-DC), thereby obtaining the data of 3595 middle school students. Two-sample t-test and χ 2 test were used to compare the incidence of NSSI among middle school students of different grades and genders, and the Model 58 test of the SPSS PROCESS component was used to analyze the mediating effect of gender-mediated depression. Results: 1) The incidence of NSSI among middle school students in Chengdu during the COVID-19 epidemic was 49.67%. The incidence of NSSI among ninth-graders (80.70%) was significantly higher than those of the eighth graders (33.82%) and seventh graders (32.32%), and the incidence of NSSI among female middle school students (54.75%) was significantly higher than that of male students (44.52%). 2) Family environment ( r=0.34, P<0.001) and depression ( r=0.50, P<0.001) were positively correlated with NSSI. 3) Depression partially mediated the effect of family environment on NSSI, with the mediating effect accounting for 64.64% of the total effect. Compared with that of male students, the positive predictive effect between family environment and depression and that between depression and NSSI in female middle school students were more significant. Conclusion: During the COVID-19 pandemic, middle school students in Chengdu had a high incidence of NSSI, which indicates that the family environment should be improved, more attention should be given to gender differences, and early screening and intervention for depression should be strengthened to reduce the incidence of NSSI.


Assuntos
COVID-19 , Comportamento Autodestrutivo , Criança , Humanos , Masculino , Feminino , Depressão/epidemiologia , Pandemias , Comportamento Autodestrutivo/epidemiologia , COVID-19/epidemiologia , Estudantes , Fatores de Risco
10.
Chemistry ; 28(47): e202201574, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35642547

RESUMO

The industrial removal of organosulfur impurities from fossil fuels relies on transition-metal-based catalysts in harsh conditions (ca. 400 °C, up to 100 bar H2 ), yet desulfurization (DS) of refractory alkyl dibenzothiophenes (DBTs) remains challenging. Here, we report that carbon-supported potassium hydride (KH/C) enables efficient DS of DBTs in mild conditions, viz. >97 % conversion of DBTs is achieved at 165 °C in 3-6 h while the yields of respective biphenyls are 84-95 % by using only 15 % excess of KH per a C-S bond. In addition, KH/C allows to lower the concentration of 4,6-Me2 DBT in the mesitylene solution from 1000 ppm to <3 ppm (165 °C, 20 h) and provides deoxygenation, denitrogenation and catalytic aromatic hydrogenation reactions. DS of various sulfur heterocycles by using KH/C, a transition-metal-free material based on earth abundant elements, is viable at low temperature and has prospects for the further development towards decentralized removal of organosulfur species from fossil fuels.

11.
Protein Expr Purif ; 197: 106108, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35533786

RESUMO

Laccases (EC 1.10.3.2) are green biocatalysts with a considerable potential in numerous environmental and industrial applications due to their abilities to oxidize a wide range of substrates, such as aromatic amines, while reducing molecular oxygen to water. In this study, a putative laccase, LacMp1, encoding a protein of 48.3 kDa and belonging to the Cu-oxidase_3 superfamily, was cloned and overexpressed in Escherichia coli with a light-induced expression system. High-level expression of recombinant protein LacMp1 was achieved under the light intensity of 6500 ± 200 lx from a white light-emitting diode (LED) belt. The purified LacMp1 showed high activity toward various laccase substrates, with the lowest Km value and highest kcat/Km value for syringaldazine at the optimal temperature and pH of 50 °C and 7.5. Dimethyl sulfoxide, ethanol, and metal ions such as Co2+, Ca2+, K+, Li+, Zn2+, Mn2+, Fe3+, and Ni2+ did not significantly inhibit the activity of LacMp1. Furthermore, LacMp1 showed tolerance to NaCl and kept 66.67 ± 2.24% of its initial activity at concentrations lower than 400 mM. Moreover, LacMp1 exhibited wide-spectrum decolorization ability towards indigoid, anthraquinonic, and azo dyes without the aid of redox mediators at pHs ranging from 5.0 to 9.0. It decolorized 99.83 ± 0.12% of indigo carmine, 99.54 ± 0.43% of Congo red, 88.41 ± 3.22% of Eriochrome black T, and 51.61 ± 1.82% of Reactive blue 4, respectively. These unusual properties demonstrated that LacMp1 had potential in specific industrial or environmental applications.


Assuntos
Escherichia coli , Lacase , Corantes/química , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Lacase/química , Marinomonas , Temperatura
12.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500559

RESUMO

A series of binary composites Bi4O5Br2/BiPO4 (PBX) was fabricated through a simple mechanical ball milling protocol. Relevant microstructural, morphological, and optical properties were thoroughly analyzed via various techniques. The integration of both components was confirmed to produce heterojunction domains at the phase boundaries. Upon exposure to visible light irradiation, the as-achieved PBX series possessed the reinforced photocatalytic NOx removal efficiencies and the weakened generation of toxic intermediate NO2 in comparison to both bare components, chiefly attributed to the efficient transport and separation of carriers and boosted production of superoxide radicals (·O2-) through the combination of a wide-bandgap ornament BiPO4 as an electron acceptor. In particular, the composite PB5 with the optimal phase composition exhibited the highest NOx removal of 40% with the lowest NO2 formation of 40 ppb among all tested candidates. According to the band structures' estimation and reactive species' detection, a reasonable mechanism was ultimately proposed to describe the migration of charge carriers and the enhancement of photocatalytic performance.


Assuntos
Luz , Oxidantes , Superóxidos
13.
Yi Chuan ; 44(7): 609-617, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858772

RESUMO

Mono-ubiquitination of histone H2B plays a critical role in the regulation of gene transcription, DNA replication, and DNA damage repair. In Schizosaccharomyces pombe, Brl2 is an E3 ubiquitin ligase and required for the ubiquitination of H2B at lysine residue 119. Currently, there are few studies related to the function of Brl2 in DNA damage repair. Using camptothecin (CPT) to induce DNA double-strand breaks (DSBs) in S. pombe, we investigated the effect of Brl2 on DSB repair, and found that brl2-null mutants showed greater sensitivity to CPT when compared with wild-type (WT) cells, as well as having a drastically reduced spontaneous recombinant frequency. The fluorescent analysis demonstrated that Brl2 was co-localized with the recombination factor Rad52 at DSBs. Moreover, Brl2 promoted the recruitment of Rad52 to DSBs. Under CPT-induced DSBs, Brl2 was phosphorylated. These findings indicate that Brl2 plays a critical role in DNA homologous recombination and its mediated repair of DSBs.


Assuntos
Quebras de DNA de Cadeia Dupla , Ubiquitina , Dano ao DNA , Reparo do DNA , Histonas/metabolismo , Ubiquitina-Proteína Ligases/genética
14.
Mater Today (Kidlington) ; 50: 149-169, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34987308

RESUMO

Triple negative breast cancer is difficult to treat effectively, due to its aggressiveness, drug resistance, and lack of the receptors required for hormonal therapy, particularly at the metastatic stage. Here, we report the development and evaluation of a multifunctional nanoparticle formulation containing an iron oxide core that can deliver doxorubicin, a cytotoxic agent, and polyinosinic:polycytidylic acid (Poly IC), a TLR3 agonist, in a targeted and simultaneous fashion to both breast cancer and dendritic cells. Endoglin-binding peptide (EBP) is used to target both TNBC cells and vasculature epithelia. The nanoparticle demonstrates favorable physicochemical properties and a tumor-specific targeting profile. The nanoparticle induces tumor apoptosis through multiple mechanisms including direct tumor cell killing, dendritic cell-initiated innate and T cell-mediated adaptive immune responses. The nanoparticle markedly inhibits tumor growth and metastasis and substantially extends survival in an aggressive and drug-resistant metastatic mouse model of triple negative breast cancer (TNBC). This study points to a promising platform that may substantially improve the therapeutic efficacy for treating metastatic TNBC.

15.
J Org Chem ; 86(23): 17110-17118, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34748343

RESUMO

A new family of π-extended BODIPY derivatives were obtained through the condensation of aldehyde and pyrrole in aqueous solution in the presence of HCl. The new rigid π-framework extends beyond the dipyrromethene unit, which is significantly different from classical BODIPYs in the electronic configuration. Both π-extended BODIPYs displayed intense absorption and moderate emission with maxima around 565 and 620 nm, respectively, and showed interesting reactivity toward various nucleophiles. Moreover, these π-extended BODIPYs were developed as fluorescent probes for rapid and selective detection of GSH and were successfully applied for live-cell imaging.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Pirróis
16.
Nano Lett ; 20(11): 8229-8235, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33054238

RESUMO

Probing and understanding the intrinsic active sites of electrocatalysts is crucial to unravel the underlying mechanism of CO2 electroreduction and provide a prospective for the rational design of high-performance electrocatalysts. However, their structure-activity relationships are not straightforward because electrocatalysts might reconstruct under realistic working conditions. Herein, we employ in-situ measurements to unveil the intrinsic origin of the InN nanosheets which served as an efficient electrocatalyst for CO2 reduction with a high faradaic efficiency of 95% for carbonaceous product. During the CO2 electroreduction, InN nanosheets reconstructed to form the In-rich surface. Density functional theory calculations revealed that the reconstruction of InN led to the redistribution of surface charge that significantly promoted the adsorption of HCOO* intermediates and thus benefited the formation of formate toward CO2 electroreduction. This work establishes a fundamental understanding on the mechanism associated with self-reconstruction of heterogeneous catalysts toward CO2 electroreduction.

17.
Inorg Chem ; 59(11): 7504-7511, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32436384

RESUMO

This work designed a nonionic extended dialdehyde 6,6'-(phenylazanediyl)dipicolinaldehyde (PDPA) for constructing Schiff-base macrocyclic complexes with weaker metal-ligand interactions, so as to solve the long-standing challenges of transmetalation and demetallization in macrocyclic complexes. An enantiomeric pair of open-oyster-like 26-membered [2 + 2] Schiff-base macrocyclic dinuclear Cd(II) complexes (S,S-1a, R,R-1b) could be obtained, having S,S/R,R-1,2-diaminocyclohexane (S,S/R,R-DACH) precursors, while Cu(II) ion template only resulted in a mononuclear Schiff-base Cu(II) acyclic complex (S,S-2) accompanied by the half-oxidation of PDPA instead of expected [2 + 2] Cu(II) macrocyclic complexes. It is suggested that the weak oxidization capability of Cu(II) ion is responsible for the formation of S,S-2 because X-ray photoelectron spectroscopy (XPS) for the solid powder of reaction mixture of direct Cu(II) ion template synthesis implies that both Cu(I) and Cu(II) species are present. In fact, corresponding [2 + 2] dinuclear Cu(II) macrocycles and even metal-free macrocycles unsuitable for direct synthesis can be obtained via Cd(II) → Cu(II) transmetalation and Na2S demetalation verified by ESI-MS and UV-vis spectra. In addition, control experiments indicate that the synthesis of metal-free macrocycles via the direct nontemplate method merely results in the mixture of multiple components of [1 + 1], [2 + 2], and [3 + 3] Schiff-base macrocycles, and they are difficult to isolate.

18.
J Biol Chem ; 293(26): 10172-10185, 2018 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-29752407

RESUMO

The formin protein dishevelled-associated activator of morphogenesis 1 (DAAM1) polymerizes straight actin filaments and mediates migration of cancer cells. However, how DAAM1 governs cell haptotaxis in response to collagen remains unexplored in breast cancer cells. We hypothesized that DAAM1 mediates invadopodia extension and cell haptotaxis in response to type IV collagen in association with integrin receptors. Using Boyden chamber membranes coated with type IV collagen, we show here that type IV collagen activates both DAAM1 and Ras homolog family member A (RHOA) and promotes haptotaxis of MDA-MB-231 and MDA-MB-453 breast cancer cells, a process abolished by treatment with the integrin αvß3 inhibitor cyclo(-RGDfK). shRNA-mediated knockdown of DAAM1 or a dominant-negative DAAM1 mutation (N-DAAM1) significantly decreased collagen-induced RHOA activity and the assembly of stress fibers, invadopodia extension, and cell haptotaxis. Immunoprecipitation and pulldown assays revealed that integrin αvß3 is associated with, but only indirectly binds to, the C-terminal DAD domain of DAAM1 in mammalian cells. Blockade of RHOA activation with a specific inhibitor (CCG-1423) or via a dominant-negative RHOA mutation (RHOA-N19) suppressed collagen-induced invadopodia extension and haptotaxis of the MDA-MB-231 and MDA-MB-453 cells. Immunoblotting and immunofluorescence assays indicated high DAAM1 and RHOA expression in invadopodia, which was abolished by cyclo(-RGDfK) treatment or DAAM1 knockdown. These findings have uncovered an integrin αvß3/DAAM1/RHOA signaling pathway for type IV collagen-induced invadopodia extension and haptotaxis in breast cancer cells. Targeting this pathway may be a means for reducing invasiveness and metastasis of breast cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/patologia , Quimiotaxia/efeitos dos fármacos , Colágeno/farmacologia , Integrina alfaVbeta3/metabolismo , Podossomos/efeitos dos fármacos , Podossomos/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas dos Microfilamentos , Transdução de Sinais/efeitos dos fármacos , Fibras de Estresse/efeitos dos fármacos , Fibras de Estresse/metabolismo , Proteínas rho de Ligação ao GTP , Proteína rhoA de Ligação ao GTP/metabolismo
20.
Cancer Cell Int ; 19: 55, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30911286

RESUMO

BACKGROUND: Dishevelled-associated activator of morphogenesis 1 (DAAM1) is a member of microfilament-related formins and mediates cell motility in breast cancer (BrCa). However, the genetic mutation status of DAAM1 mRNA and its correlation with pathological characteristics are still unclearly. Methods: A patient cohort and BrCa cells were recruited to demonstrate the role of functional SNP in microRNA-208a-5p binding site of DAAM1 3'-UTR and underlying mechanism in BrCa metastasis. METHODS: A patient cohort and BrCa cells were recruited to demonstrate the role of functional SNP in microRNA-208a-5p binding site of DAAM1 3'-UTR and underlying mechanism in BrCa metastasis. RESULTS: The expression and activation of DAAM1 increased markedly in lymphnode metastatic tissues. A genetic variant (rs79036859 A/G) was validated in the miR-208a-5p binding site of DAAM1 3'-UTR. The G genotype (AG/GG) was a risk genotype for the metastasis of BrCa by reducing binding affinity of miR-208a-5p for the DAAM1 3'-UTR. Furthermore, the miR-208a-5p expression level was significantly suppressed in lymphnode metastatic tissues compared with that in non-lymphnode metastatic tissues. Overexpression of miR-208a-5p inhibited DAAM1/RhoA signaling pathway, thereby leading to the decrease of the migratory ability. CONCLUSION: Overall, the rs79036859 G variant of DAAM1 3'-UTR was identified as a relevant role in BrCa metastasis via the diversity of miR-208a-5p binding affinity.

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