Lattice Doping of Lanthanide Ions in Cs2AgInCl6 Nanocrystals Enabling Tunable Photoluminescence

Lead-free halide double perovskite Cs2AgInCl6 has become the research hotspot in the optoelectronic fields. It is a challenge to utilize the lattice doping by different lanthanide ions with rich and unique photoluminescence (PL) emissions for emerging photonic applications. Here, we successfully incorporated Dy3+, Sm3+, and Tb3+ ions into Cs2AgInCl6 nanocrystals (NCs) by the hot-injection method, bringing diverse PL emissions of yellowish, orange, and green light in Cs2AgInCl6:Ln3+ (Ln3+ = Dy3+, Sm3+, Tb3+). Moreover, benefiting from the energy transfer process, Sm3+ and Tb3+ ion-codoped Cs2AgInCl6 NCs achieved tunable emission from green to yellow orange and a fluorescent pattern from the as-prepared NC-hexane inks by spray coating was made to show its potential application in fluorescent signs and anticounterfeiting technology. This work indicates that lanthanide ions could endow Cs2AgInCl6 NCs the unique and tunable PL properties and stimulate the development of lead-free halide perovskite materials for new optoelectronic applications.

A Description and Examination of Fluorescence in Nine North American Firefly Species (Coleoptera: Lampyridae)

Fluorescence across the family Lampyridae has been documented sporadically but not comprehensively in formal research. Fireflies (Coleoptera: Lampyridae), best known for their bioluminescence, are also fluorescent. This fluorescence has been documented in several genera within the clade but is still an often overlooked aspect of firefly physiology in the common understanding of the species. To this end, the purpose of this study was to document and describe the fluorescence in nine species of North American fireflies, across three genera. Each species was photographed and a description of the fluorescent pattern was provided, as well as measurements of the specific spectral sensitivity of the fluorescent excitation and emission wavelengths. These data are intended to provide an identification guide of sorts to different firefly fluorescence, as well as documenting definitively its presence in several firefly genera.

Is anti-HMGB1 Antibody a Potential Characteristic Autoantibody for Sjögren's Syndrome?

BACKGROUND: Sjögren's syndrome (SS) is a common chronic inflammatory autoimmune disease, affects about 0.33% to 0.77% population in China. The positive for antinuclear antibodies (ANA) is one of the key features of SS, which show typical granular pattern in indirect immunofluorescent antibody test (IIFT). About 70% SS patients have the anti-SS-A and/or SS-B antibodies, which indicates other autoantibodies in SS patients.METHODS: The anti-HMGB1 antibody in 93 SS patients and 96 healthy controls were investigated with in-house built ELISA and immunoblotting; and the location of HMGB1 and fluorescent pattern of anti-HMGB1 antibody were investigated with IIFT. The contribution of anti-HMGB1 antibody in ANA-IF with Cas9-induce HMGB1 knockout cells were also detected.RESULTS: The anti-HMGB1 antibody in SS patients (9.96±5.55 VS 4.9±1.4 RU/ml RU/ml compared to healthy controls) increased. With ROC curve analysis, when taking 8 RU/ml as the cutoff value, the sensitivity, specificity, and the area under the curve were 64.5%, 96.9% and 0.83, respectively. A total of 18 patients (20.7%) with granular pattern in ANA-IF test were anti-HMGB1 antibody positive only. With commercial antibody, the fluorescent pattern of anti-HMGB1 antibody showed typical granular pattern. The serum from ANA-IF (+), SS-A (-), and SS-B (-) SS patients showed typical granular pattern in wildtype B16 cells, but no fluorescence in HMGB1 knockout B16 cells.CONCLUSIONS: Anti-HMGB1 antibody may be one of the characteristic autoantibodies of SS except anti-SS-A and SS-B. The detection of anti-HMGB1 antibody can provide more laboratory evidence for clinical diagnosis of SS.

Pericentromere clustering in Tradescantia section Rhoeo involves self-associations of AT- and GC-rich heterochromatin fractions, is developmentally regulated, and increases during differentiation

A spectacular but poorly recognized nuclear repatterning is the association of heterochromatic domains during interphase. Using base-specific fluorescence and extended-depth-of-focus imaging, we show that the association of heterochromatic pericentromeres composed of AT- and GC-rich chromatin occurs on a large scale in cycling meiotic and somatic cells and during development in ring- and bivalent-forming Tradescantia spathacea (section Rhoeo) varieties. The mean number of pericentromere AT-rich domains per root meristem nucleus was ca. half the expected diploid number in both varieties, suggesting chromosome pairing via (peri)centromeric regions. Indeed, regular pairing of AT-rich domains was observed. The AT- and GC-rich associations in differentiated cells contributed to a significant reduction of the mean number of the corresponding foci per nucleus in relation to root meristem. Within the first 10 mm of the root, the pericentromere attraction was in progress, as if it was an active process and involved both AT- and GC-rich associations. Complying with Rabl arrangement, the pericentromeres preferentially located on one nuclear pole, clustered into diverse configurations. Among them, a strikingly regular one with 5–7 ring-arranged pericentromeric AT-rich domains may be potentially engaged in chromosome positioning during mitosis. The fluorescent pattern of pachytene meiocytes and somatic nuclei suggests the existence of a highly prescribed ring/chain type of chromocenter architecture with side-by-side arranged pericentromeric regions. The dynamics of pericentromere associations together with their non-random location within nuclei was compared with nuclear architecture in other organisms, including the widely explored Arabidopsis model.

The ERG1 Potassium Channel is More Abundant in Skeletal Muscle from Cachectic than Healthy Humans

Background: The ERG1a potassium channel has been detected in the atrophying skeletal muscle of mice experiencing either muscle disuse or cancer cachexia and further evidenced to contribute to muscle deterioration by enhancing ubiquitin proteolysis; however, to our knowledge, ERG1 has not been reported in human skeletal muscle. Methods and Results: Here, using immunohistochemistry, we detect ERG1 immunofluorescence in human Rectus abdominis skeletal muscle sarcolemma. Further, using single point brightness data, we report detection of ERG1 immunofluorescence at low levels in the Rectus abdominis muscle sarcolemma of young adult humans and show that it trends toward greater levels (10.6%) in healthy aged adults. Interestingly, we detect ERG1 immunofluorescence at a statistically greater level (53.6%; p<0.05) in the skeletal muscle of older people having cancer cachexia than in age-matched adults. Importantly, using immunoblot, we reveal that ERG1 protein is 38% (p<0.09) more abundant in the skeletal muscle of cachectic older adults than in healthy age-matched controls. Additionally, we report that the ERG1 fluorescent pattern is consistent with I-band localization. Conclusions: The data suggest that ERG1 may be related to muscle loss in humans and is located in t-tubules where it could influence calcium handling.

Fluorescent pattern recognition of metal ions by nanoparticles of bovine serum albumin as a chemical nose/tongue

A sensor array mimicking a chemical nose/tongue based on bovine serum albumin nanoparticles (BSANsn) has been developed for the fluorescence pattern recognition of metal ions in biofluids.

Palladium(II) Complex with Tridentate Ligand Containing Pyrenyl Core

A series of ligands containing pyrenyl core which are PyEt1, PyEt2, and PyEt3 have been successfully synthesized. PyEt2, a bidentate ligand and PyEt3, a tridentate ligand were used to prepared Pd(II) complexes by reactions with PdCl2(CH3CN)2. The titled compounds displayed intriguing geometries around the central palladium atoms. 1H-NMR results showed that palladium in Pd-PyEt3 adopts a five-coordinate configuration. Keywords: Pyrene, palladium, five coordination. References: [1] M. Zhao, X. Zhou, J. Tang, Z. Deng, X. Xu, Z. Chen, X. Li, L. Yang, L.-J. Ma, Pyrene excimer-based fluorescent sensor for detection and removal of Fe3+ and Pb2+ from aqueous solutions, Spectrochim Acta A. 173 (2017) 235-240. https://doi.org/10.1016/j.saa.2016.09.033.[2] H. Turhan, E. Tukenmez, B. Karagoz, N. Bicak, Highly fluorescent sensing of nitroaromatic explosives in aqueous media using pyrene-linked PBEMA microspheres, Talanta. 179 (2018) 107-114. https://doi.org/10.1016/j.talanta.2017.10.061.[3] N. Li, L. Qi, J. Qiao, Y. Chen, Ratiometric Fluorescent Pattern for Sensing Proteins Using Aqueous Polymer-Pyrene/γ-Cyclodextrin Inclusion Complexes, Anal. Chem. 88 (2016) 1821-1826. https://doi.org/10.1021/acs.analchem.5b04112.[4] G. Sivaraman, T. Anand, D. Chellappa, Pyrene based selective-ratiometric fluorescent sensing of zinc and pyrophosphate ions, Anal. Methods. 6 (2014) 2343-2348. https://doi.org/10.1039/c3ay 42057d.[5] D. Fernández, M.I. García-Seijo, T. Kégl, G. Petőcz, L. Kollár, M.E. García-Fernández, Preparation and Structural Characterization of Ionic Five-Coordinate Palladium(II) and Platinum(II) Complexes of the Ligand Tris[2-(diphenylphosphino)ethyl]phosphine. Insertion of SnCl2 into M−Cl Bonds (M = Pd, Pt) and Hydroformylation Activity of the Pt−SnCl3 Systems, Inorg. Chem. 41 (2002) 4435-4443. https://doi.org/10.1021/ic020006k.