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1.
ACS Nano ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049478

RESUMO

The tailored spatial polarization of coherent light beams is important for applications ranging from microscopy to biophysics to quantum optics. Miniaturized light sources are needed for integrated, on-chip photonic devices with desired vector beams; however, this issue is unresolved because most lasers rely on bulky optical elements to achieve such polarization control. Here, we report on quantum dot-plasmon lasers with engineered polarization patterns controllable by near-field coupling of colloidal quantum dots to metal nanoparticles. Conformal coating of CdSe-CdS core-shell quantum dot films on Ag nanoparticle lattices enables the formation of hybrid waveguide-surface lattice resonance (W-SLR) modes. The sidebands of these hybrid modes at nonzero wavevectors facilitate directional lasing emission with either radial or azimuthal polarization depending on the thickness of the quantum dot film.

2.
Insect Sci ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32039551

RESUMO

Swarming behavior facilitates pair formation, and therefore mating, in many eusocial termites. However, the physiological adjustments and morphological transformations of the flight muscles involved in flying and flightless insect forms are still unclear. Here, we found that the dispersal flight of the eusocial termite Reticulitermes chinensis Snyder led to a gradual decrease in ATP supply from oxidative phosphorylation, as well as a reduction in the activities of critical mitochondrial respiratory enzymes from preflight to dealation. Correspondingly, using three-dimensional reconstruction and transmission electron microscopy (TEM), the flight muscles were found to be gradually deteriorated during this process. In particular, two tergo-pleural muscles (IItpm5 and IIItpm5) necessary to adjust the rotation of wings for wing shedding behavior were present only in flying alates. These findings suggest that flight muscle systems varied in function and morphology to facilitate the swarming flight procedure, which sheds light on the important role of swarming in successful extension and fecundity of eusocial termites. This article is protected by copyright. All rights reserved.

3.
Chin J Traumatol ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32057563

RESUMO

Trauma is the leading cause of death in people under the age of 45 years, and it has gained wide attention from academics worldwide. Therefore, more and more studies have reported on trauma and related fields in recent decades. In 2019, Chinese Journal of Traumatology (CJTEE) published 69 articles covering traffic medicine, wound healing, bone trauma, emergency care, and other hot topics of traumatology. Here we reviewed a series of articles published in CJTEE on the topics mentioned above, try to give a brief introduction of progress in trauma field.

4.
Redox Biol ; : 101453, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32057709

RESUMO

Currently, most antioxidants do not show any favorable clinical outcomes in reducing myocardial ischemia-reperfusion (I/R) injury, suggesting an urgent need for exploring a new regulator of redox homeostasis in I/R hearts. Here, using heart-specific transgenic (TG) and knockdown (KD) mouse models, tumor susceptibility gene 101 (Tsg101) is defined as a novel cardiac-protector against I/R-triggered oxidative stress. RNA sequencing and bioinformatics data surprisingly reveal that most upregulated genes in Tsg101-TG hearts are transcribed by Nrf2. Accordingly, pharmacological inhibition of Nrf2 offsets Tsg101-elicited cardio-protection. Mechanistically, Tsg101 interacts with SQSTM1/p62 through its PRR domain, and promotes p62 aggregation, leading to recruitment of Keap1 for degradation by autophagosomes and release of Nrf2 to the nucleus. Furthermore, knockout of p62 abrogates Tsg101-induced cardio-protective effects during I/R. Hence, our findings uncover a previously unrecognized role of Tsg101 in the regulation of p62/Keap1/Nrf2 signaling cascades and provide a new strategy for the treatment of ischemic heart disease.

5.
Nano Lett ; 20(2): 1468-1474, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32004007

RESUMO

We report how the direction of quantum dot (QD) lasing can be engineered by exploiting high-symmetry points in plasmonic nanoparticle (NP) lattices. The nanolaser architecture consists of CdSe-CdS core-shell QD layers conformally coated on two-dimensional square arrays of Ag NPs. Using waveguide-surface lattice resonances (W-SLRs) near the Δ point in the Brillouin zone as optical feedback, we achieved lasing from the gain in CdS shells at off-normal emission angles. Changing the periodicity of the plasmonic lattices enables other high-symmetry points (Γ or M) of the lattice to overlap with the QD shell emission, which facilitates tuning of the lasing direction. We also increased the thickness of the QD layer to introduce higher-order W-SLR modes with additional avoided crossings in the band structure, which expands the selection of cavity modes for any desired lasing emission angle.

6.
J Med Microbiol ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32043953

RESUMO

Introduction. Staphylococcal enterotoxin B (SEB) is an extensively studied super-antigen. A previous study by us suggested that SEB exposure during pregnancy could alter the percentage of CD4+ and CD8+ T cells in the peripheral blood of neonatal offspring rats.Aim. It is unknown whether SEB exposure during pregnancy can influence the development of regulatory T cells (Tregs) in the peripheral blood of neonatal offspring rats.Methodology. Pregnant rats at gestational day 16 were intravenously injected with 15 µg SEB. Peripheral blood was acquired from neonatal offspring rats on days 1, 3 and 5 after delivery and from adult offspring rats for determination of Treg number by cytometry, cytokines by ELISA, and FoxP3 expression by real-time PCR and western blot.Results. SEB given to pregnant rats significantly increased the absolute number of Tregs and the expression levels of FoxP3, IL-10 and TGF-ß (P<0.05, P<0.01) in the peripheral blood of not only neonatal but also adult offspring rats. Furthermore, repeated SEB exposure in adult offspring rats significantly decreased the absolute number of Tregs (P<0.01), and the expression levels of FoxP3, IL-10 and TGF-ß (P<0.05, P<0.01) in their peripheral blood.Conclusion. Prenatal SEB exposure attenuates the development and function of Tregs to repeated SEB exposure in the peripheral blood of adult offspring rats.

7.
Commun Biol ; 3(1): 25, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932716

RESUMO

In innate immunity, multiple autophagic processes eliminate intracellular pathogens, but it remains unclear whether noncanonical autophagy and xenophagy are coordinated, and whether they occur concomitantly or sequentially. Here, we show that Streptococcus pneumoniae, a causative of invasive pneumococcal disease, can trigger FIP200-, PI3P-, and ROS-independent pneumococcus-containing LC3-associated phagosome (LAPosome)-like vacuoles (PcLVs) in an early stage of infection, and that PcLVs are indispensable for subsequent formation of bactericidal pneumococcus-containing autophagic vacuoles (PcAVs). Specifically, we identified LC3- and NDP52-delocalized PcLV, which are intermediates between PcLV and PcAV. Atg14L, Beclin1, and FIP200 were responsible for delocalizing LC3 and NDP52 from PcLVs. Thus, multiple noncanonical and canonical autophagic processes are deployed sequentially against intracellular S. pneumoniae. The Atg16L1 WD domain, p62, NDP52, and poly-Ub contributed to PcLV formation. These findings reveal a previously unidentified hierarchical autophagy mechanism during bactericidal xenophagy against intracellular bacterial pathogens, and should improve our ability to control life-threating pneumococcal diseases.

8.
Oncogene ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988451

RESUMO

Cancer-associated fibroblasts (CAFs) are activated fibroblasts that constitute the major components of tumor microenvironment (TME) and play crucial roles in tumor development and metastasis. Here, we generated fibroblast-specific inducible focal adhesion kinase (FAK) knockout (cKO) mice in a breast cancer model to study potential role and mechanisms of FAK signaling in CAF to promote breast cancer metastasis in vivo. While not affecting primary tumor development and growth, FAK deletion significantly suppressed breast cancer metastasis in vivo. Analyses of CAFs derived from cKO mice as well as human CAFs showed that FAK is required for their activity to promote mammary tumor cell migration. We further showed that FAK ablation in CAFs decreased exosome functions to promote tumor cell migration and other activities, which could contribute to the reduced metastasis observed in cKO mice. Lastly, profiling of miRs from CAF exosomes showed alterations of several exosomal miRs in FAK-null CAFs, and further analysis suggested that miR-16 and miR-148a enriched in exosomes from FAK-null CAFs contribute to the reduced tumor cell activities and metastasis. Together, these results identify a new role for FAK signaling in CAFs that regulate their intercellular communication with tumor cells to promote breast cancer metastasis.

9.
Antonie Van Leeuwenhoek ; 113(2): 293-301, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31583494

RESUMO

A Gram-stain negative, aerobic, non-flagellated, non-gliding, rod-shaped bacterium, designated strain YLY04T, was isolated from the gut microflora of a sea bass (Dicentrarchus labrax L.) collected from the coast of Yuanyao Wharf, Weihai, China. Growth was found to occur at pH 6.0-9.0 (optimum, 7.0-8.0), 4-37 °C (optimum, 28-30 °C) in the presence of 0-11.0% (w/v) NaCl (optimum, 3.0-4.0%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YLY04T is closely related to Pelagivirga sediminicola BH-SD19T and Roseovarius antarcticus M-S13-148T. Strain YLY04T contains ubiquinone-10 as the sole respiratory quinone and summed feature 8 (C18:1ω7c and/or C18:1ω6c), cyclo-C19:0ω8c, C16:0 and 11-methyl-C18:1ω7c as the major fatty acids. The polar lipids of strain YLY04T were found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, an unidentified phospholipid and three unidentified lipids. The DNA G+C content was determined to be 62.7 mol%. The phenotypic, chemotaxonomic and phylogenetic properties, and genome analysis, indicated that strain YLY04T represents a novel species within the genus Pelagivirga, for which the name Pelagivirga dicentrarchi sp. nov. is proposed. The type strain is YLY04T (= MCCC 1H00334T = KCTC 62452T).

10.
Neurogastroenterol Motil ; 32(1): e13719, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31574212

RESUMO

BACKGROUND: Low-grade inflammation may be involved in the pathogenesis of functional dyspepsia (FD). We hypothesis that altered gastric permeability is involved in the onset and persistence of this disorder. Therefore, our aim was to evaluate gastric mucosal integrity and mast cell numbers in patients with FD. METHODS: We enrolled 58 patients with FD fulfilling the Rome III criteria (H Pylori negative), 20 inflammatory control subjects (H Pylori positive), and 20 healthy controls (H Pylori negative). Probe-based confocal endomicroscopy was performed using intravenous fluorescein to assess the paracellular fluorescein leakage and cell shedding. Mast cells were identified with quantitative immunohistochemistry on mucosal biopsies. KEY RESULTS: Endomicroscopic score of paracellular permeability was significantly higher in H pylori-negative FD patients compared with healthy controls (1.45 ± 1.27 vs 3.69 ± 3.18, P = .006). However, FD patients and healthy controls did not show differences in cell shedding score (0.75 ± 0.79 vs 1.29 ± 1.14, P = .069). Mast cell numbers were significantly increased compared with healthy control samples (18.91 ± 5.47 vs 14.1 ± 3.88, P < .001). The magnitude of increase in permeability was positively correlated with mast cell numbers of FD patients (rs = .6588, P < .0001), but not dyspepsia symptom scores. CONCLUSION AND INFERENCES: Impaired gastric barrier function is present in FD patients. This might provide a new pathophysiological mechanism and therapeutical target in FD.

11.
Waste Manag ; 101: 180-187, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622863

RESUMO

With the rapid development of photovoltaic industry, the recycling of waste solar photovoltaic (PV) panels is becoming a critical and global challenge. Considering PV panels recycling is significantly effective and worthwhile to save natural resources and reduce the cost of production, how to selectively recycle valuable components of PV panels is the hot and dominant topic. Different from current mechanical crushing, heat treatment and chemical operation processes, novel and environment-friendly recycling approaches by using high voltage pulse discharge in water, called high voltage fragmentation (HVF), was discussed under different discharge conditions. The results showed that discharging across surface and interior of PV panels produced ablation round holes, sputter metal particles and dendritic channels. The average particle size decreased with the ascent of pulse number and voltage amplitude. Considering the energy consumption, the optimal condition of HVF in this paper was 160 kV for 300 pulses with the energy consumption of 192.99 J/g, crushing the PV panels into particles of 4.1 mm in average (13.7% of the initial size). More particle was distributed among the 0.1-2 mm size fractions as the energy increased. Selective fragmented products, such as Cu, Al, Pb, Ag and Sn, are concentrated on the fractions under 1 mm. Finally, hybrid crushing energy consumption model combined with fractal theory was discussed, which presented close relationship between energy and average particle size. Walker's model (n = 2.047 determined by fractal theory) had the best fitting effect.


Assuntos
Resíduo Eletrônico , Metais , Reciclagem
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1912-1918, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839059

RESUMO

OBJECTIVE: To explore the effect of the expression regulation of mitotic control protein DIS3 on the proliferation ability of 3 cell Lines of human myeloma. METHODS: Human myeloma cell lines NCI-h929, RPMI 8226 and U266B1 were selected as study objects, and the over-expression vector of DIS3 gene and DIS3-siRNA were designed and constructed, respectively. The cell experiments were divided into 5 groups: control, DIS3 over-expression-empty vector, DIS3-siRNA negative control, DIS3 over-expression and DIS3-siRNA group. After culture for 24 h, 48 h and 72 h, the proliferation capacity of these three cell lines was measured by MTT assay. And cell samples were collected after culture for 72 h, the expression of proliferation cell nuclear antigen (PCNA) was detected by RT-qPCR and Western blot. RESULTS: MTT assay results showed that the proliferation capacity of cells in DIS3 over-expression group was significantly reduced, as compared with the DIS3 over-expression-empty vector group at the same time point (24, 48 or 72 h) (P<0.05, P<0.01). Compared with DIS3-siRNA negative control group at the same time point (24, 48 or 72 h), the proliferation capacity of cells in the DIS3-siRNA group significantly increased (P<0.05, P<0.01). The results of RT-qPCR and Western blot showed that the mRNA and protein expression levels of PCNA in cells of DIS3 over-expression group were significantly reduced, as compared with DIS3 over-expression empty vector group (P<0.01). Compared with the DIS3-siRNA negative control group, the mRNA and protein expression of PCNA in the cells of DIS3-siRNA group very significantly increased (P<0.01). CONCLUSION: Over expression of DIS3 can significantly reduce the proliferation ability of 3 cell lines of human myeloma, which may be closely related with reducing PCNA expression.


Assuntos
Mieloma Múltiplo , Linhagem Celular Tumoral , Proliferação de Células , Complexo Multienzimático de Ribonucleases do Exossomo , Humanos , RNA Interferente Pequeno , Transfecção
13.
Artigo em Inglês | MEDLINE | ID: mdl-31860426

RESUMO

A novel Gram-stain-negative, facultatively anaerobic, flagellated and spiral-shaped bacterium, designated WDS2A16AT was isolated from a marine solar saltern in Weihai, PR China. Growth was observed at 20-40 °C (optimal 33-37 °C), 1-15 % (w/v) NaCl (optimal 3-4 %) and pH 6.0-9.0 (optimal pH 7.5). Major cellular fatty acids (>10 %) were C18 : 1ω7c and C16 : 0. Phosphatidylglycerol, diphosphatidylglycerol and an unidentified glycolipid were detected as the predominant polar lipids. The sole respiratory quinone was Q-8. The DNA G+C content of strain WDS2A16AT was 48.5 mol%. The 16S rRNA gene sequence similarities of WDS2A16AT with other species were less than 91 %. The average nucleotide identity, in silico DNA-DNA hybridization and amino acid identity of strain WDS2A16AT with the most related strain Gynuella sunshinyii YC6258 T were 66.1, 19.3 and 48.1 %, respectively. Comparative analysis of 16S rRNA gene sequences and phenotypic characterization indicated that strain WDS2A16AT represents a novel species in a new genus, for which the name Salinibius halmophilus gen. nov., sp. nov. is proposed. The type strain is WDS2A16AT (=KCTC 52225T=MCCC 1H00139T).

14.
Inorg Chem ; 58(22): 15008-15012, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31689092

RESUMO

A series of lanthanide-titanium oxo clusters (LnTOCs), Ln2Ti8-Ac, Ln2Ti8-p-Toluic, and Ln2Ti8-Anthra (Ln = Eu and Tb), were prepared based on acetic acid (HAc), p-toluic acid (Hp-Toluic), and anthracene-9-carboxylic acid (HAnthra). Crystal structural analysis showed that these clusters possess the same metal topology framework, in which eight Ti4+ ions form a cube and two Ln3+ ions are located on the opposite faces of the cube. The luminescence investigation discovered that the Eu2Ti8-Ac displays the highest quantum yields with 15.6%, and the conjugation effect of ligand substituents can lower the triplet state energy of ligands, thus regulating the luminescence quantum yield of the Ln2Ti8 clusters. These results suggest that the triplet excited-state energy of the ligands should match well with the energy levels of Ln3+ to enhance the luminescence.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31661055

RESUMO

A novel Gram-stain-negative, strictly aerobic, rod-shaped, non-motile and yellow-pigmented bacterial strain, designated T58T, was isolated from a marine sediment sample collected from the coastal area of Weihai, PR China. Strain T58T was most closely related to Hyunsoonleella pacifica SW033T with 97.1 % 16S rRNA gene sequence similarity, followed by Hyunsoonleella jejuensis KCTC 22242T (96.9 %). Based on 16S rRNA gene sequences, the phylogenetic analysis indicated that strain T58T represented a member of the genus Hyunsoonleella within the family Flavobacteriaceae of the phylum Bacteroidetes. Strain T58T was found to grow optimally at 30 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0 % (w/v) NaCl. The major fatty acids were iso-C15  :  0, iso-C15 : 1 G, iso-C17 : 0 3-OH and iso-C15 : 0 3-OH. The major isoprenoid quinone was menaquinone 6 (MK-6). The major polar lipids were phosphatidylethanolamine, two unidentified aminolipids and two unidentified lipids. The DNA G+C content of the genomic DNA was 35.0 mol%. On the basis of its phylogenetic, phenotypic and chemotaxonomic characteristics, strain T58T is considered to represent a novel species of the genus Hyunsoonleella, for which the name Hyunsoonleella flava sp. nov. is proposed. The type strain is T58T (=KCTC 72081T=MCCC 1H00359T).

16.
Kardiol Pol ; 77(12): 1163-1169, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31664016

RESUMO

BACKGROUND: Ischemic cardiomyopathy (ICM) leads to heart failure by causing apoptosis of cardiac myocytes. It is generally believed that a therapy targeting apoptosis of cardiac myocytes would improve the prognosis of patients with ischemic heart disease. AIMS: We aimed to investigate the role of Rho GTPase­activating protein 1 (ARHGAP1) in ICM. METHODS: The cellular model of myocardial ischemia (H9c2 cell model) and a rat model of ICM were established to explore the expression of ARHGAP1. The overexpression of ARHGAP1 was induced in H9c2 myocardial cells to assess protein function. RESULTS: The expression of ARHGAP1 as a result of hypoxic conditions in the cellular and rat models was observed. Its overexpression induced apoptosis of cultured H9c2 cells under normal atmospheric conditions. ARHGAP1 was also shown to initiate the apoptosis pathway by regulating the cell death modulators B­cell lymphoma 2 (Bcl­2) and Bcl­2­associated X protein. CONCLUSIONS: Our results show that the ARHGAP1 expression is closely associated with apoptosis of myocardial cells, which in turn leads to ICM. Thus, ARHGAP1 may become a novel molecular marker of the hypoxia­induced apoptosis pathway and serve as a potential therapeutic target in patients with ICM.

17.
Acc Chem Res ; 52(11): 2997-3007, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31596570

RESUMO

Rationally assembled nanostructures exhibit distinct physical and chemical properties beyond their individual units. Developments in nanofabrication techniques have enabled the patterning of a wide range of nanomaterial designs over macroscale (>in.2) areas. Periodic metal nanostructures show long-range diffractive interactions when the lattice spacing is close to the wavelength of the incident light. The collective coupling between metal nanoparticles in a lattice introduces sharp and intense plasmonic surface lattice resonances, in contrast to the broad localized resonances from single nanoparticles. Plasmonic nanoparticle lattices exhibit strongly enhanced optical fields within the subwavelength vicinity of the nanoparticle unit cells that are 2 orders of magnitude higher than that of individual units. These intense electromagnetic fields can manipulate nanoscale processes such as photocatalysis, optical spectroscopy, nonlinear optics, and light harvesting. This Account focuses on advances in exciton-plasmon coupling and light-matter interactions with plasmonic nanoparticle lattices. First, we introduce the fundamentals of ultrasharp surface lattice resonances; these resonances arise from the coupling of the localized surface plasmons of a nanoparticle to the diffraction mode from the lattice. Second, we discuss how integrating dye molecules with plasmonic nanoparticle lattices can result in an architecture for nanoscale lasing at room temperature. The lasing emission wavelength can be tuned in real time by adjusting the refractive index environment or varying the lattice spacing. Third, we describe how manipulating either the shape of the unit cell or the lattice geometry can control the lasing emission properties. Low-symmetry plasmonic nanoparticle lattices can show polarization-dependent lasing responses, and multiscale plasmonic superlattices-finite patches of nanoparticles grouped into microscale arrays-can support multiple plasmon resonances for controlled multimodal nanolasing. Fourth, we discuss how the assembly of photoactive emitters on the nanocavity arrays behaves as a hybrid materials system with enhanced exciton-plasmon coupling. Positioning metal-organic framework materials around nanoparticles produces mixed photon modes with strongly enhanced photoluminescence at wavelengths determined by the lattice. Deterministic coupling of quantum emitters in two-dimensional materials to plasmonic lattices leads to preserved single-photon emission and reduced decay lifetimes. Finally, we highlight emerging applications of nanoparticle lattices from compact, fully reconfigurable imaging devices to solid-state emitter structures. Plasmonic nanoparticle lattices are a versatile, scalable platform for tunable flat optics, nontrivial topological photonics, and modified chemical reactivities.

18.
Microb Cell Fact ; 18(1): 180, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31647018

RESUMO

BACKGROUND: Structurally stable α-galactosidases are of great interest for various biotechnological applications. More thermophilic α-galactosidases with high activity and structural stability have therefore to be mined and characterized. On the other hand, few studies have been performed to prominently enhance the AOX1 promoter activity in the commonly used Pichia pastoris system, in which production of some heterologous proteins are insufficient for further study. RESULTS: ReGal2 encoding a thermoactive α-galactosidase was identified from the thermophilic (hemi)cellulolytic fungus Rasamsonia emersonii. Significantly increased production of ReGal2 was achieved when ReGal2 was expressed in an engineered Pastoris pichia expression system with a modified AOX1 promoter and simultaneous fortified expression of Mxr1 that is involved in transcriptionally activating AOX1. Purified ReGal2 exists as an oligomer and has remarkable thermo-activity and thermo-tolerance, exhibiting maximum activity of 935 U/mg towards pNPGal at 80 °C and retaining full activity after incubation at 70 °C for 60 h. ReGal2 is insensitive to treatments by many metal ions and exhibits superior tolerance to protein denaturants. Moreover, ReGal2 efficiently hydrolyzed stachyose and raffinose in soybeans at 70 °C in 3 h and 24 h, respectively. CONCLUSION: A modified P. pichia expression system with significantly enhanced AOX1 promoter activity has been established, in which ReGal2 production is markedly elevated to facilitate downstream purification and characterization. Purified ReGal2 exhibited prominent features in thermostability, catalytic activity, and resistance to protein denaturants. ReGal2 thus holds great potential in relevant biotechnological applications.

19.
Nat Mater ; 18(11): 1172-1176, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31548631

RESUMO

Miniaturized lasers are an emerging platform for generating coherent light for quantum photonics, in vivo cellular imaging, solid-state lighting and fast three-dimensional sensing in smartphones1-3. Continuous-wave lasing at room temperature is critical for integration with opto-electronic devices and optimal modulation of optical interactions4,5. Plasmonic nanocavities integrated with gain can generate coherent light at subwavelength scales6-9, beyond the diffraction limit that constrains mode volumes in dielectric cavities such as semiconducting nanowires10,11. However, insufficient gain with respect to losses and thermal instabilities in nanocavities has limited all nanoscale lasers to pulsed pump sources and/or low-temperature operation6-9,12-15. Here, we show continuous-wave upconverting lasing at room temperature with record-low thresholds and high photostability from subwavelength plasmons. We achieve selective, single-mode lasing from Yb3+/Er3+-co-doped upconverting nanoparticles conformally coated on Ag nanopillar arrays that support a single, sharp lattice plasmon cavity mode and greater than wavelength λ/20 field confinement in the vertical dimension. The intense electromagnetic near-fields localized in the vicinity of the nanopillars result in a threshold of 70 W cm-2, orders of magnitude lower than other small lasers. Our plasmon-nanoarray upconverting lasers provide directional, ultra-stable output at visible frequencies under near-infrared pumping, even after six hours of constant operation, which offers prospects in previously unrealizable applications of coherent nanoscale light.

20.
J Biol Inorg Chem ; 24(8): 1159-1170, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31486954

RESUMO

Alzheimer's disease (AD) is a type of neurodegenerative malady that is associated with the accumulation of amyloid plaques. Metal ions are critical for the development and upkeep of brain activity, but metal dyshomeostasis can contribute to the development of neurodegenerative diseases, including AD. This review highlights the association between metal dyshomeostasis and AD pathology, the feasibility of rebalancing metal homeostasis as a therapeutic strategy for AD, and a survey of current drugs that action via rebalancing metal homeostasis. Finally, we discuss the challenges that should be overcome by researchers in the future to enable the practical use of metal homeostasis rebalancing agents for clinical application.

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