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1.
J Am Chem Soc ; 146(15): 10640-10654, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568727

RESUMO

Foreign ions as additives are of great significance for realizing excellent control over the morphology of noble metal nanostructures in the state-of-the-art seed-mediated growth method; however, they remain largely unexplored in chiral synthesis. Here, we report on a Cu2+-dominated chiral growth strategy that can direct the growth of concave chiral Au nanoparticles with C3-dominant chiral centers. The introduction of trace amounts of Cu2+ ions in the seed-mediated chiral growth process is found to dominate the chirality transfer from chiral molecules to chiral nanoparticles, leading to the formation of chiral nanoparticles with a concave VC geometry. Both experimental and theoretical results further demonstrate the correlation between the nanoparticle structure and optical chirality for the concave chiral nanoparticle. The Cu2+ ion is found to dominate the chiral growth by selectively activating the deposition of Au atoms along the [110] and [111] directions, facilitating the formation of the concave VC. We further demonstrate that the Cu2+-dominated chiral growth strategy can be employed to generate a variety of concave chiral nanoparticles with enriched geometric chirality and desired chiroptical properties. Concave chiral nanoparticles also exhibit appealing catalytic activity and selectivity toward electrocatalytic oxidation of enantiomers in comparison to helicoidal nanoparticles. The ability to tune the geometric chirality in a controlled manner by simply manipulating the Cu2+ ions as additives opens up a promising strategy for creating chiral nanomaterials with increasing architectural diversity for chirality-dependent optical and catalytic applications.

2.
Mol Biol Evol ; 40(2)2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36625090

RESUMO

Evolution of sequence-specific transcription factors clearly drives lineage-specific innovations, but less is known about how changes in the central transcriptional machinery may contribute to evolutionary transformations. In particular, transcriptional regulators are rich in intrinsically disordered regions that appear to be magnets for evolutionary innovation. The C-terminal Binding Protein (CtBP) is a transcriptional corepressor derived from an ancestral lineage of alpha hydroxyacid dehydrogenases; it is found in mammals and invertebrates, and features a core NAD-binding domain as well as an unstructured C-terminus (CTD) of unknown function. CtBP can act on promoters and enhancers to repress transcription through chromatin-linked mechanisms. Our comparative phylogenetic study shows that CtBP is a bilaterian innovation whose CTD of about 100 residues is present in almost all orthologs. CtBP CTDs contain conserved blocks of residues and retain a predicted disordered property, despite having variations in the primary sequence. Interestingly, the structure of the C-terminus has undergone radical transformation independently in certain lineages including flatworms and nematodes. Also contributing to CTD diversity is the production of myriad alternative RNA splicing products, including the production of "short" tailless forms of CtBP in Drosophila. Additional diversity stems from multiple gene duplications in vertebrates, where up to five CtBP orthologs have been observed. Vertebrate lineages show fewer major modifications in the unstructured CTD, possibly because gene regulatory constraints of the vertebrate body plan place specific constraints on this domain. Our study highlights the rich regulatory potential of this previously unstudied domain of a central transcriptional regulator.


Assuntos
Proteínas Repressoras , Fatores de Transcrição , Animais , Proteínas Repressoras/genética , Proteínas Repressoras/química , Filogenia , Fatores de Transcrição/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Drosophila/metabolismo , Vertebrados/metabolismo , Processamento Alternativo , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Ligação Proteica , Fosfoproteínas/genética , Mamíferos/metabolismo
3.
Small ; : e2401506, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38431925

RESUMO

Reaching rapid reaction kinetics of oxygen reduction (ORR) and oxygen evolution reactions (OER) is critical for realizing efficient rechargeable zinc-air batteries (ZABs). Herein, a novel CoNi-CoN3 composite site containing CoNi alloyed nanoparticles and CoN3 moieties is first constructed in N-doped carbon nanosheet matrix (CoNi-CoN3 /C). Benefiting from the high electroactivity of CoNi-CoN3 composite sites and large surface area, CoNi-CoN3 /C shows a superior half-wave potential (0.88 V versus RHE) for ORR and a small overpotential (360 mV) for OER at 10 mA cm-2 . Theoretical calculations have demonstrated that the introduction of CoNi alloys has modulated the electronic distributions near the CoN3 moiety, inducing the d-band center of CoNi-CoN3 composite site to shift down, thus stabilizing the valence state of Co active sites and balancing the adsorption of OER/ORR intermediates. Accordingly, the reaction energy trends exhibit optimized overpotentials for OER/ORR, leading to superior battery performances. For aqueous and flexible quasi-solid-state rechargeable ZABs with CoNi-CoN3 /C as catalyst, a large power density (250 mW cm-2 ) and high specific capacity (804 mAh g-1 ) are achieved. The in-depth understanding of the electroactivity enhancement mechanism of interactive metal nanoparticles and metal coordinated with nitrogen (MNx ) moieties is crucial for designing novel high-performance metal/nitrogen-doped carbon (M─N─C) catalysts.

4.
Chembiochem ; 25(12): e202400105, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38639074

RESUMO

Cell senescence is defined as irreversible cell cycle arrest, which can be triggered by telomere shortening or by various types of genotoxic stress. Induction of senescence is emerging as a new strategy for the treatment of cancer, especially when sequentially combined with a second senolytic drug capable of killing the resulting senescent cells, however severely suffering from the undesired off-target side effects from the senolytic drugs. Here, we prepare a bimetalic platinum-aluminum salen complex (Alumiplatin) for cancer therapy-a combination of pro-senesence chemotherapy with in situ senotherapy to avoid the side effects. The aluminum salen moiety, as a G-quadruplex stabilizer, enhances the salen's ability to induce cancer cell senescence and this phenotype is in turn sensitive to the cytotoxic activity of the monofunctional platinum moiety. It exhibits an excellent capability for inducing senescence, a potent cytotoxic activity against cancer cells both in vitro and in vivo, and an improved safety profile compared to cisplatin. Therefore, Alumiplatin may be a good candidate to be further developed into safe and effective anticancer agents. This novel combination of cell senescence inducers with genotoxic drugs revolutionizes the therapy options of designing multi-targeting anticancer agents to improve the efficacy of anticancer therapies.


Assuntos
Alumínio , Antineoplásicos , Senescência Celular , Etilenodiaminas , Platina , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Senescência Celular/efeitos dos fármacos , Platina/química , Platina/farmacologia , Alumínio/química , Alumínio/farmacologia , Animais , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Camundongos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química
5.
J Fish Dis ; 46(2): 99-112, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36263741

RESUMO

The Streptomyces lateritius Z1-26 was isolated from soil samples which showed broad-spectrum antibacterial activity against a broad range of fish pathogens. The In Vivo Imaging System (IVIS) monitored that strain Z1-26 could survive and colonize in the gills and abdomen of crucian carp. The effects of dietary supplementation with strain Z1-26 were evaluated with respect to the growth performance, antioxidant capacity, and immune response of crucian carp. The results showed that the Z1-26-fed fish had a significantly higher growth rate than the fish fed the control diet. The immune and antioxidant parameters revealed that the non-specific immune indicators (AKP, SOD, and LZM) of the serum, the expression of immune-related genes (IgM, C3, and LZM), and antioxidant-related genes (Nrf2 and Keap1) of the immune organs were significantly increased, whereas the expression of pro-inflammatory factors (IL-1ß, IL-8, and TNF-α) of the immune organs was significantly down-regulated in crucian carp fed strain Z1-26 compared with fish fed a control diet. Moreover, fish fed with Z1-26 supplemented diets showed a significantly improved survival rate after Aeromonas hydrophila infection. In addition, the whole genome analysis showed that strain Z1-26 possesses 28 gene clusters, including 6 polyketide synthetase (PKS), 4 non-ribosomal peptide-synthetase (NRPS), 1 bacteriocin, and 1 lantipeptide. In summary, these results indicated that strain Z1-26 could improve the growth performance and disease resistance in crucian carp, and has the potential to be developed as a candidate probiotics for the control of bacterial diseases in aquaculture.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Animais , Carpa Dourada/genética , Carpas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Antioxidantes/metabolismo , Doenças dos Peixes/microbiologia , Fator 2 Relacionado a NF-E2/metabolismo , Dieta , Antibacterianos/farmacologia , Aeromonas hydrophila/fisiologia , Proteínas de Peixes/genética , Ração Animal/análise
6.
Comput Inform Nurs ; 41(6): 426-433, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36225163

RESUMO

Text-mining algorithms can identify the most prevalent factors of risk-benefit assessment on the use of complementary and integrative health approaches that are found in healthcare professionals' written notes. The aims of this study were to discover the key factors of decision-making on patients' complementary and integrative health use by healthcare professionals and to build a consensus-derived decision algorithm on the benefit-risk assessment of complementary and integrative health use in diabetes. The retrospective study of an archival dataset used a text-mining method designed to extract and analyze unstructured textual data from healthcare professionals' responses. The techniques of classification, clustering, and extraction were performed with 1398 unstructured clinical notes made by healthcare professionals between 2019 and 2020. The most important factor for decision-making by healthcare professionals about complementary and integrative health use in patients with diabetes was the ingredients of the product. Other important factors were the patient's diabetes control, the undesirable effects from complementary and integrative health, evidence-based complementary and integrative health, medical laboratory data, and the product's affordability. This exploratory text-mining study provides insight into how healthcare professionals decide complementary and integrative health use for patients with diabetes after a risk-benefit assessment from clinical narrative notes.


Assuntos
Terapias Complementares , Diabetes Mellitus , Humanos , Estudos Retrospectivos , Diabetes Mellitus/terapia , Mineração de Dados/métodos , Atenção à Saúde
7.
Int J Mol Sci ; 23(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897806

RESUMO

The number of inflorescence branches is an important agronomic character of tomato. The meristem differentiation and development pattern of tomato inflorescence is complex and its regulation mechanism is very different from those of other model plants. Therefore, in order to explore the cause of tomato inflorescence branching, transcriptome analysis was conducted on two kinds of tomato inflorescences (single racemes and compound inflorescences). According to the transcriptome data analysis, there were many DEGs of tomato inflorescences at early, middle, and late stages. Then, GO and KEGG enrichments of DEGs were performed. DEGs are mainly enriched in metabolic pathways, biohormone signaling, and cell cycle pathways. According to previous studies, DEGs were mainly enriched in metabolic pathways, and FALSIFLORA (FA) and ANANTHA (AN) genes were the most notable of 41 DEGs related to inflorescence branching. This study not only provides a theoretical basis for understanding inflorescence branching, but also provides a new idea for the follow-up study of inflorescence.


Assuntos
Inflorescência , Solanum lycopersicum , Seguimentos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Inflorescência/genética , Solanum lycopersicum/genética , Meristema/genética , Transcriptoma
8.
BMC Cancer ; 21(1): 1326, 2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34895168

RESUMO

BACKGROUND: Survival times differ among patients with advanced gastric carcinoma. A precise and universal prognostic evaluation strategy has not yet been established. The current study aimed to construct a prognostic scoring model for mortality risk stratification in patients with advanced gastric carcinoma. METHODS: Patients with advanced gastric carcinoma from two hospitals (development and validation cohort) were included. Cox proportional hazards regression analysis was conducted to identify independent risk factors for survival. A prognostic nomogram model was developed using R statistics and validated both in bootstrap and external cohort. The concordance index and calibration curves were plotted to determine the discrimination and calibration of the model, respectively. The nomogram score and a simplified scoring system were developed to stratify patients in the two cohorts. RESULTS: Development and validation cohort was comprised of 401 and 214 gastric cancer patients, respectively. Mucinous or non-mucinous histology, ECOG score, bone metastasis, ascites, hemoglobin concentration, serum albumin level, lactate dehydrogenase level, carcinoembryonic antigen level, and chemotherapy were finally incorporated into prognostic nomogram. The concordance indices were 0.689 (95% CI: 0.664 ~ 0.714) and 0.673 (95% CI: 0.632 ~ 0.714) for bootstrap and external validation. 100 and 200 were set as the cut-off values of nomogram score, patients in development cohort were stratified into low-, intermediate- and high-risk groups with median overall survival time 15.8 (95% CI: 12.2 ~ 19.5), 8.4 (95% CI: 6.7 ~ 10.2), and 3.9 (95% CI: 2.7 ~ 5.2) months, respectively; the cut-off values also worked well in validation cohort with different survival time in subgroups. A simplified model was also established and showed good consistency with the nomogram scoring model in both of development and validation cohorts. CONCLUSION: The prognostic scoring model and its simplified surrogate can be used as tools for mortality risk stratification in patients with advanced gastric carcinoma.


Assuntos
Recidiva Local de Neoplasia , Nomogramas , Neoplasias Gástricas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Medição de Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
9.
Phys Chem Chem Phys ; 23(41): 23748-23757, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34643191

RESUMO

CuZrO3 has been hypothesized to be a catalytic material with potential applications for CO2 reduction. Unfortunately, this material has received limited attention in the literature, and to the best of our knowledge the exact crystal structure is still unknown. To address this challenge, we utilize several different structural prediction techniques in concert, including the Universal Structure Predictor: Evolutionary Xtallography (USPEX), the Materials Project Structure Predictor, and the Open Quantum Materials Database (OQMD). Leveraging these structural prediction techniques in conjunction with Density-Functional Theory (DFT) calculations, we determine a possible structure for CuZrO3, which resembles a "sandwich" morphology. Our calculations reveal that this new structure is significantly lower in energy than a previously hypothesized perovskite structure, albeit it still has a thermodynamic preference to decompose into CuO and ZrO2. In addition, we experimentally tried to synthesize CuZrO3 based on literature reports and compared computational to experimental X-ray Diffraction (XRD) patterns confirming that the final product is a mixture of CuO and ZrO2. Finally, we conducted a computational surface energetics and CO2 adsorption study on our discovered sandwich morphology, demonstrating that CO2 can adsorb and activate on the material. However, these CO2 adsorption results deviate from previously reported results further confirming that the CuZrO3 is a metastable form and may not be experimentally accessible as a well-mixed oxide, since phase segregation to CuO and ZrO2 is preferred. Taken together, our combined computational and experimental study provides evidence that the synthesis of CuZrO3 is extremely difficult and if this oxide exists, it should have a sandwich-like morphology.

10.
Int J Mol Sci ; 22(22)2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34830429

RESUMO

Inflorescences are the main factor affecting fruit yield. The quantity and quality of inflorescences are closely related to fruit quality and yield. The presence of compound inflorescences in cherry tomatoes is well established, and it has been discovered by chance that compound racemes also exist in tomatoes. To explore the formation of compound inflorescences in tomato, transcriptome sequencing was performed on Moneymaker (MM) and Compound Inflorescence (CI) plants. In-florescences were collected in three periods (early, middle and late) in three replicates, for a total of 18 samples. Data analysis showed that the DEGs were most enriched in metabolic pathways and plant hormone signal transduction pathways. The DEGs were also enriched in the cell cycle pathway, photosynthesis pathway, carbon metabolism pathway and circadian rhythm pathway. We found that the FALSIFLORA (FA), COMPOUND INFLORESCENCE (S) and ANANTHA (AN) genes were involved in compound inflorescence development, not only revealing novel genes but also providing a rich theoretical basis for compound inflorescence development.


Assuntos
Genoma de Planta/genética , Inflorescência/genética , Solanum lycopersicum/genética , Fatores de Transcrição/genética , Flores/genética , Frutas/genética , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/genética , Proteínas de Plantas/genética
11.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360893

RESUMO

Flowering is a morphogenetic process in which angiosperms shift from vegetative growth to reproductive growth. Flowering time has a strong influence on fruit growth, which is closely related to productivity. Therefore, research on crop flowering time is particularly important. To better understand the flowering period of the tomato, we performed transcriptome sequencing of early flower buds and flowers during the extension period in the later-flowering "Moneymaker" material and the earlier-flowering "20965" homozygous inbred line, and we analyzed the obtained data. At least 43.92 million clean reads were obtained from 12 datasets, and the similarity with the tomato internal reference genome was 92.86-94.57%. Based on gene expression and background annotations, 49 candidate genes related to flowering time and flower development were initially screened, among which the greatest number belong to the photoperiod pathway. According to the expression pattern of candidate genes, the cause of early flowering of "20965" is predicted. The modes of action of the differentially expressed genes were classified, and the results show that they are closely related to hormone regulation and participated in a variety of life activities in crops. The candidate genes we screened and the analysis of their expression patterns provide a basis for future functional verification, helping to explore the molecular mechanism of tomato flowering time more comprehensively.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/genética , Flores/crescimento & desenvolvimento , Flores/genética , Genes de Plantas , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/genética , Transcriptoma , Produtos Agrícolas/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Estudos de Associação Genética/métodos , Solanum lycopersicum/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , RNA-Seq/métodos , Transdução de Sinais/genética
12.
Nat Mater ; 18(2): 108-112, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30598539

RESUMO

Higher-order topological insulators1-5 are a family of recently predicted topological phases of matter that obey an extended topological bulk-boundary correspondence principle. For example, a two-dimensional (2D) second-order topological insulator does not exhibit gapless one-dimensional (1D) topological edge states, like a standard 2D topological insulator, but instead has topologically protected zero-dimensional (0D) corner states. The first prediction of a second-order topological insulator1, based on quantized quadrupole polarization, was demonstrated in classical mechanical6 and electromagnetic7,8 metamaterials. Here we experimentally realize a second-order topological insulator in an acoustic metamaterial, based on a 'breathing' kagome lattice9 that has zero quadrupole polarization but a non-trivial bulk topology characterized by quantized Wannier centres2,9,10. Unlike previous higher-order topological insulator realizations, the corner states depend not only on the bulk topology but also on the corner shape; we show experimentally that they exist at acute-angled corners of the kagome lattice, but not at obtuse-angled corners. This shape dependence allows corner states to act as topologically protected but reconfigurable local resonances.

13.
Fish Shellfish Immunol ; 98: 632-640, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31669281

RESUMO

In this study, a Streptomyces strain was isolated from the soil samples of Yanghu Wetland Park in Changsha, Hunan Province. This strain showed excellent antimicrobial activity against 10 fish pathogens, as indicated by the results of the agar-diffusion and oxford cup assays. After 16s rDNA sequencing and physiological & biochemical analyses, it was identified as Streptomyces amritsarensis, namely for S. amritsarensis N1-32. Cytotoxicity test was performed, and the results exhibited that this strain had no toxicity to hepatic L8824 cell line from grass carp liver. The diets supplemented strain N1-32 at concentrations of 1 × 107 cfu/g and 1 × 109 cfu/g was used to feed fish. After 28 days, the expression levels of antioxidant-related genes Nrf2 and Keap1 in the liver and spleen were significantly up-regulated, and the expression of immune-related gene IgM was notably increased in the liver, kidney, head-kidney, and spleen. Toll-like receptor 4 (TLR4) gene expression was up-regulated in the spleen, and TLR4, myeloid differentiation factor 88 (MyD88) gene were up-regulated in the kidney. The survival rate of grass carp was significantly improved after pathogen infection. Whole-genome analysis of N1-32 showed that the strain harbored related genes, capability for producing substances that enhance the immunity of grass carp and inhibit pathogens. A total of 22 gene clusters were identified in the genome, including 5 terpene gene clusters, 4 nonribosomal peptide-synthetase (NRPS) gene clusters and 2 lantipeptide gene clusters. In summary, these results showed that strain N1-32 as a feed additive could regulate grass carp immunity and enhance the resistance of grass carp against fish pathogens.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/metabolismo , Bactérias/efeitos dos fármacos , Expressão Gênica , Imunidade Humoral , Probióticos/farmacologia , Streptomyces/química , Ração Animal/análise , Dieta/veterinária , Expressão Gênica/efeitos dos fármacos , Genoma Bacteriano , Imunidade Humoral/efeitos dos fármacos , Probióticos/administração & dosagem , Streptomyces/genética
14.
J Am Chem Soc ; 141(33): 13003-13007, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31381855

RESUMO

Incorporating open metal sites (OMS) into metal-organic frameworks allows design of well-defined binding sites for selective molecular adsorption, which has a profound impact on catalysis and separations. We demonstrate that Cu(I) sites incorporated into MFU-4l preferentially adsorb olefins over paraffins. Density functional theory (DFT) calculations show that the OMS are independent, with no dependence of binding energy on olefin loading up to one olefin per Cu(I). Experimentally, increasing Cu(I) loading increased olefin uptake without affecting the binding energy, as predicted by DFT and confirmed by temperature-programmed desorption. The potential of this material for olefin/paraffin separation under ambient conditions was investigated by gas adsorption and column breakthrough experiments for an equimolar ratio of olefin/paraffin. High-grade propylene and ethylene (>99.999%) can be generated using temperature-concentration swing recycling from a Cu(I)-MFU-4l packed column with no measurable paraffin breakthrough.

15.
Phys Rev Lett ; 122(24): 244301, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31322389

RESUMO

The recent discovery of higher-order topological insulators (TIs) has opened new possibilities in the search for novel topological materials and metamaterials. Second-order TIs have been implemented in two-dimensional (2D) systems exhibiting topological "corner states," as well as three-dimensional (3D) systems having one-dimensional (1D) topological "hinge states." Third-order TIs, which have topological states three dimensions lower than the bulk (which must thus be 3D or higher), have not yet been reported. Here, we describe the realization of a third-order TI in an anisotropic diamond-lattice acoustic metamaterial. The bulk acoustic band structure has nontrivial topology characterized by quantized Wannier centers. By direct acoustic measurement, we observe corner states at two corners of a rhombohedronlike structure, as predicted by the quantized Wannier centers. This work extends topological corner states from 2D to 3D, and may find applications in novel acoustic devices.

16.
Appl Microbiol Biotechnol ; 103(21-22): 8987-8999, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31637491

RESUMO

This study evaluated the inhibition and interaction of Bacillus velezensis BvL03 as a probiotic agent against Aeromonas hydrophila. Strain BvL03 isolated from sediment samples of fish ponds had excellent antimicrobial activity against several fish pathogenic bacteria, especially Aeromonas, including A. hydrophila, A. veronii, A. caviae, and A. sobria. The successful amplification of lipopeptide antimicrobial chemical biosynthetic genes, including iturin family (ituA, ituB, and ituD), bacillomycin family (bacA, bacD, and bacAB), surfactin family (srfAB, srfC, and srfAA), and subtilosin family (albF and sunT) from the genome of BvL03 strain, confirmed its predominant antimicrobial activity. The challenge test suggested that BvL03 significantly decreased fish mortality when challenged with A. hydrophila, which had a cumulative mortality of 12.5% in the treatment group. Toxicity and hemolytic activity of A. hydrophila after co-cultured with BvL03 were relieved as confirmed by the cell experiments, when the initial inoculated concentration of BvL03 was 109 cfu/mL or higher. Moreover, the BvL03 strain labeled with GFP protein (BvL03-GFP) and AhX040 strain labeled with mCherry protein (AhX040-mCherry) were injected into grass carps. The fluorescence levels were monitored by using In Vivo Imaging System (IVIS), in which the green color was steadily increasing, whereas the red color was gradually weakening. Whole genome sequencing revealed that strain BvL03 possesses 15 gene clusters related to antibacterial compounds, including 5 NRPS gene clusters and 3 PKS gene clusters. These results suggested that B. velezensis BvL03 has the potential to be developed as a probiotic candidate against A. hydrophila infection in aquaculture.


Assuntos
Aeromonas hydrophila/fisiologia , Antibiose/fisiologia , Bacillus/fisiologia , Agentes de Controle Biológico/metabolismo , Carpas/microbiologia , Doenças dos Peixes/microbiologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bacteriocinas/genética , Bacteriocinas/metabolismo , Doenças dos Peixes/prevenção & controle , Lipopeptídeos/genética , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/metabolismo , Probióticos , Sequenciamento Completo do Genoma
17.
Nanotechnology ; 29(26): 265401, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-29638218

RESUMO

CdS/TiO2 heterojunction film used as a photoanode has attracted much attention in the past few years due to its good visible light photocatalytic activity. However, CdS/TiO2 films prepared by conventional methods (successive ionic layer adsorption and reaction, chemical bath deposition and electrodeposition) show numerous grain boundaries in the CdS layer and an imperfect contact at the heterojunction interface. In this study, we designed a phase transformation method to fabricate CdS/TiO2 nanorod heterojunction films. The characterization results showed that the CdS layer with fewer grain boundaries was conformally coated on the TiO2 nanorod surface and the formation mechanism has been explained in this manuscript. Moreover, the prepared CdS/TiO2 films show a high photocatalytic activity and the photocurrent density is as high as 9.65 mA cm-2 at 0.80 V versus RHE. It may be attributed to fewer grain boundaries and a compact heterojunction contact, which can effectively improve charge separation and transportation.

18.
Matern Child Nutr ; 14(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28752645

RESUMO

Caesarean section is associated with weaker newborn suction pressure. This nonblinded, randomized trial explored the effect of suction pressures generating by a breast pump on mothers' onset of lactation and milk supply after caesarean section. A high pressure group (-150 mmHg), a low pressure group (-100 mmHg), and a control group (none) were generated under computer random assignment with concealed allocation in 2 tertiary hospitals. The breast pumping began within 2 hr after caesarean operation (6 times a day and 30 min per time) until onset of lactation. The primary outcomes were the timing of onset of lactation, milk supply, and mother's satisfaction in lactation, using both intention-to-treat and per-protocol analyses. The secondary endpoints were the pumping-related pain, nipple injury, and maternal fatigue. All 164 women randomized were included in analysis. The breast pumping at -150 mmHg optimally advanced the timing of the onset of lactation and increased daytime milk supply. The pumping also appeared to boost mothers' confidence in lactation. The results in the per-protocol population (n = 148) were consistent with those of intention-to-treat population (n = 164). However, the pumping aggravated maternal nipple pain and fatigue, though there was no statistical significance. The findings suggest that a higher pumping pressure within the range of normal vaginally born infant suction could promote onset of lactation and milk supply among mothers giving birth by caesarean section. The pumping could also enhance mothers' confidence in breastfeeding.


Assuntos
Extração de Leite/efeitos adversos , Cesárea/efeitos adversos , Lactação , Satisfação do Paciente , Autoimagem , Adulto , Povo Asiático , China , Fadiga/etiologia , Fadiga/fisiopatologia , Fadiga/prevenção & controle , Feminino , Humanos , Análise de Intenção de Tratamento , Mamilos/lesões , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/fisiopatologia , Dor Pós-Operatória/prevenção & controle , Pacientes Desistentes do Tratamento , Período Pós-Parto , Gravidez , Pressão/efeitos adversos , Índice de Gravidade de Doença , Centros de Atenção Terciária , Adulto Jovem
19.
Phys Rev Lett ; 118(19): 194301, 2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28548530

RESUMO

The emerging field of topological acoustics that explores novel gauge-field-related phenomena for sound has drawn attention in recent years. However, previous approaches constructing a synthetic gauge field for sound predominantly relied on a periodic system, being unable to form a uniform effective magnetic field, thus lacking access to some typical magnetic-induced quantum phenomena such as Landau energy quantization. Here we introduce strain engineering, previously developed in graphene electronics and later transferred to photonics, into a two-dimensional acoustic structure in order to form a uniform effective magnetic field for airborne acoustic wave propagation. Landau levels in the energy spectrum can be formed near the Dirac cone region. We also propose an experimentally feasible scheme to verify the existence of acoustic Landau levels with an acoustic measurement. As a new freedom of constructing a synthetic gauge field for sound, our study offers a path to previously inaccessible magneticlike effects in traditional periodic acoustic structures.

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