Stable Tunable Luminescence of Hetero-valent Eu Ion Activated Ba2InTaO6 Phosphors Synthesized by Defect-Induced Self-Reduction in the Molten-Salt Method.

Functional materials with stable and adjustable luminescence have recently become a research hotspot for their broad application prospects. Tunable luminescence can be realized by the doping of hetero-valent europium ions. High-temperature hydrogen atmosphere reduction is required in the traditional preparation of Eu2+-doped phosphors. Herein, an anoxic molten-salt medium environment was established to form oxygen vacancy defects in the reaction system and induce the self-reduction of Eu3+ ions to obtain Eu2+ ions. X-ray photoelectron spectroscopy (XPS) results confirm the existence of Eu2+ and Eu3+ ions in the samples, and the fluorescence spectrum shows that hetero-valent Eu ions can synergistically emit light effectively. Under 266 nm ultraviolet light excitation, the white light emission was successfully realized for a Ba2InTaO6:Eu phosphor by different emission combinations of Eu3+ and Eu2+ ions. In addition, the Ba2InTaO6:Eu phosphor exhibits adjustable luminescence from greenish-yellow to red exciting at 390-490 nm, which has superior stability in a high-temperature and high-humidity environment. Therefore, it is very promising that Ba2InTaO6:Eu will be used as multi-color functional materials in many fields such as communication encryption and colorful decoration.

Reversible Single-Crystal-to-Single-Crystal Transformation of a Coordination Polymer through Solar-Switchable Cycloaddition and Cycloreversion Reaction.

Reversible covalent reactions within crystalline complexes are powerful tools for the design and developing of new generation of reusable smart materials. In this work, a unique photoreactive olefin-containing metal-organic coordination polymer [Ag2(2,3-ppe)2(1,3-bdc)]n (1) was prepared by the hydrothermal reaction between AgNO3, 1-(2-pyridyl)-2-(3-pyridyl)ethylene (2,3-ppe), and 1,3-benzenedicarboxylic acid (1,3-H2bdc). When exposed to sunlight, 1 can undergo single-crystal-to-single-crystal (SCSC) transformation to form [Ag2(dpdpcb)(1,3-bdc)]n (1a, dpdpcb = 1,3-di(2-pyridyl)-2,4-di(3-pyridyl)cyclobutane) through a [2 + 2] cycloaddition reaction. 1a can regenerate into 1 via the cycloreversion reaction based on the thermal effect of sunlight. Such a metal-organic complex exhibits interesting fluorescence switching behavior during the unprecedented fully solar-controlled reversible SCSC reaction, which makes it possible to be applied to the fields of optical memory storage and anti-counterfeiting.

Crystallographic Visualization of a Guest-Induced Solar-Driven Cycloaddition Reaction Based on a Recyclable Nonporous Coordination Polymer.

Stimuli-responsive solids with adjustable photophysical properties are particularly attractive because they can be used as smart materials in anticounterfeiting, information storage, holographic imaging, and other fields. Herein, we report a unique nonporous coordination polymer, {[Ag(3,3'-dpe)](2,2'-Hbpdc)}n (1; 3,3'-dpe = 1,2-dipyridin-3-ylethene and 2,2'-H2bpdc = 2,2'-biphenyldicarboxylic acid), that can convert to an extremely photoreactive compound, 1·H2O·MeCN (MeCN = acetonitrile), through guest capture. Upon irradiation of sunlight, 1·H2O·MeCN can transform to {[Ag(3,3'-tpcb)0.5](2,2'-Hbpdc)(H2O)(MeCN)}n (2·H2O·MeCN; 3,3'-tpcb = 1,2,3,4-tetrapyridin-3-ylcyclobutane). 2·H2O·MeCN can lose its solvent molecules to form 2 and further return to 1 at high temperature. Accompanied by direct visualization based on multistep single-crystal-to-single-crystal conversions, the recyclable crystalline solid exhibits remarkable fluorescence changes, which makes it a supramolecular switch for application in multiple anticounterfeiting.

Kandelia candel Thioredoxin f Confers Osmotic Stress Tolerance in Transgenic Tobacco.

Water deficit caused by osmotic stress and drought limits crop yield and tree growth worldwide. Screening and identifying candidate genes from stress-resistant species are a genetic engineering strategy to increase drought resistance. In this study, an increased concentration of mannitol resulted in elevated expression of thioredoxin f (KcTrxf) in the nonsecretor mangrove species Kandelia candel. By means of amino acid sequence and phylogenetic analysis, the mangrove Trx was classified as an f-type thioredoxin. Subcellular localization showed that KcTrxf localizes to chloroplasts. Enzymatic activity characterization revealed that KcTrxf recombinant protein possesses the disulfide reductase function. KcTrxf overexpression contributes to osmotic and drought tolerance in tobacco in terms of fresh weight, root length, malondialdehyde (MDA) content, and hydrogen peroxide (H2O2) production. KcTrxf was shown to reduce the stomatal aperture by enhancing K+ efflux in guard cells, which increased the water-retaining capacity in leaves under drought conditions. Notably, the abscisic acid (ABA) sensitivity was increased in KcTrxf-transgenic tobacco, which benefits plants exposed to drought by reducing water loss by promoting stomatal closure. KcTrxf-transgenic plants limited drought-induced H2O2 in leaves, which could reduce lipid peroxidation and retain the membrane integrity. Additionally, glutathione (GSH) contributing to reactive oxygen species (ROS) scavenging and transgenic plants are more efficient at regenerating GSH from oxidized glutathione (GSSG) under conditions of drought stress. Notably, KcTrxf-transgenic plants had increased glucose and fructose contents under drought stress conditions, presumably resulting from KcTrxf-promoted starch degradation under water stress. We conclude that KcTrxf contributes to drought tolerance by increasing the water status, by enhancing osmotic adjustment, and by maintaining ROS homeostasis in transgene plants.

Controllable Fluorescence Switching of a Coordination Chain Based on the Photoinduced Single-Crystal-to-Single-Crystal Reversible Transformation of a syn-[2.2]Metacyclophane.

The observation of a reversible chemical transformation corresponding to an external stimulus in the solid state is intriguing in the exploration of smart materials, which can potentially be applied in molecular machines, molecular switches, sensors, and data storage devices. The solid-state photodimerization reaction of 1,3-bis[2-(4-pyridyl)ethenyl]benzene (1,3-bpeb) in a one-dimensional coordination polymer {[Cd2(1,3-bpeb)2(4-FBA)4]·H2O}n (4-FBA = 4-fluorobenzoate) with 365 nm UV light afforded syn-tetrakis(4-pyridyl)-1,2,9,10-diethano[2.2]metacyclophane (syn-tpmcp) in quantitative yield via a single-crystal-to-single-crystal (SCSC) transformation. Upon irradiation with 254 nm UV light, an SCSC conversion from syn-tpmcp to 1,3-bpeb was also achieved in quantitative yield within the syn-tpmcp-supported coordination polymer {[Cd2(syn-tpmcp)(4-FBA)4]·H2O}n. In particular, accompanied by the reversible transformation between 1,3-bpeb and syn-tpmcp, the coordination chain exhibits photocontrollable fluorescence-switching behavior, which makes this intelligent material an appealing candidate for practical applications.

Safety profiles of iron chelators in young patients with haemoglobinopathies.

BACKGROUND: This review describes the safety of deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX) and combined therapy in young patients less than 25 yr of age with haemoglobinopathies. METHODS: Searches in electronic literature databases were performed. Studies reporting adverse events associated with iron chelation therapy were included. Study and reporting quality was assessed using AHRQ Risk of Bias Assessment Tool and McMaster Quality Assessment Scale of Harms. Prospective clinical studies were pooled in a random-effects meta-analysis of proportions. RESULTS: Safety data of 2040 patients from 34 studies were included. Ninety-two case reports of 246 patients were identified. DFX (937 patients) and DFP (667 patients) possess the largest published safety evidence. Fewer studies on combination regimens are available. Increased transaminases were seen in all regimens (3.9-31.3%) and gastrointestinal disorders with DFP and DFX (3.7-18.4% and 5.8-18.8%, respectively). Therapy discontinuations due to adverse events were low (0-4.1%). Reporting quality was selective and poor in most of the studies. CONCLUSION: Iron chelation therapy is generally safe in young patients, and published data correspond to summary of product characteristics. Each iron chelation regimen has its specific safety risks. DFO seems not to be associated with serious adverse effects in recommended doses. In DFP and DFX, rare, but serious, adverse reactions can occur. Data on combined therapy are scarce, but it seems equally safe compared to monotherapy.

MCE: Medical Cognition Embedded in 3D MRI feature extraction for advancing glioma staging.

In recent years, various data-driven algorithms have been applied to the classification and staging of brain glioma MRI detection. However, the restricted availability of brain glioma MRI data in purely data-driven deep learning algorithms has presented challenges in extracting high-quality features and capturing their complex patterns. Moreover, the analysis methods designed for 2D data necessitate the selection of ideal tumor image slices, which does not align with practical clinical scenarios. Our research proposes an novel brain glioma staging model, Medical Cognition Embedded (MCE) model for 3D data. This model embeds knowledge characteristics into data-driven approaches to enhance the quality of feature extraction. Approach includes the following key components: (1) Deep feature extraction, drawing upon the imaging technical characteristics of different MRI sequences, has led to the design of two methods at both the algorithmic and strategic levels to mimic the learning process of real image interpretation by medical professionals during film reading; (2) We conduct an extensive Radiomics feature extraction, capturing relevant features such as texture, morphology, and grayscale distribution; (3) By referencing key points in radiological diagnosis, Radiomics feature experimental results, and the imaging characteristics of various MRI sequences, we manually create diagnostic features (Diag-Features). The efficacy of proposed methodology is rigorously evaluated on the publicly available BraTS2018 and BraTS2020 datasets. Comparing it to most well-known purely data-driven models, our method achieved higher accuracy, recall, and precision, reaching 96.14%, 93.4%, 97.06%, and 97.57%, 92.80%, 95.96%, respectively.

Topological structural transformation of a two-dimensional coordination polymer via single-crystal to single-crystal photoreaction.

Photoreactive coordination polymers are particularly important media for the implementation of highly-selective photoreactions and creation of photoresponsive intelligent materials and devices. Herein, a two-dimensional (2D) photoreactive coordination polymer, formulated as [Cd(pha)(3,3'-bpe)]n (1) was prepared through the hydrothermal reaction between Cd(NO3)2·4H2O, phthalic acid (H2pha) and 1,2-bis(3-pyridyl)ethylene (3,3'-bpe). Upon exposure to 365 nm UV light, the 1H NMR spectroscopy and single crystal X-ray diffraction analysis results indicated that 1 can undergo a [2 + 2] photocycloaddition reaction and thus form a new coordination polymer [Cd(pha)(3,3'-tpcb)0.5]n (1a) through single-crystal to single-crystal (SCSC) transformation. Accompanied by the SCSC photoreaction, the 2D sql net of 1 converted into a 2D binodal network of 1a with the rare (324·627)(326272) topology. The SCSC transformation from 1 to 1a also exhibits an interesting photocontrolled fluorescence. The unique photoinduced structural change and fluorescence quenching of 1 makes it a potential intelligent material for optical anti-counterfeiting, fluorescence sensors and other fields.

catena-Poly[[[tetra-aqua-nickel(II)]-µ-4,4'-bipyridyl-κN:N'] 3,3'-(p-phenyl-ene)diacrylate].

In the title compound, {[Ni(C(10)H(8)N(2))(H(2)O)(4)](C(12)H(8)O(4))}(n), the Ni(II), 4,4'-bipyridyl (bipy) and 3,3'-(p-phenyl-ene)diacrylate (L(2-)) moieties are situated on inversion centres. The bipy ligands bridge Ni(II) ions into positively charged polymeric chains along [101]. The Ni(II) atom is coordinated by two N atoms from two bipy ligands and four water mol-ecules in a distorted octa-hedral geometry. L(2-) anions inter-act with the polymeric chains via O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network.

Poly[(µ(2)-1,3-di-4-pyridyl-propane)(µ(3)-1,3-phenyl-enediacetato)-cadmium].

In the title compound, [Cd(C(10)H(8)O(4))(C(13)H(14)N(2))](n), two symmetry-related Cd atoms are bridged by two carboxyl-ate O atoms into a binuclear Cd(2) subunit around an inversion center. The Cd atom has a distorted penta-gonal-bipyramidal environment, defined by five O atoms from three different 1,3-phenylendiacetate (1,3-pda) ligands and two N atoms from two 1,3-di-4-pyridyl-propane (bpp) ligands. Each Cd(2) subunit is linked to four different Cd(2) subunits by four 1,3-pda ligands and four bpp ligands, forming a two-dimensional network with rhombic grids (12.50 × 12.50 Å(2)) extending along the ab plane.

Benzene-1,3-dicarb-oxy-lic acid-1,2-bis-(4-pyrid-yl)ethene (1/1).

In the title compound, C(12)H(10)N(2)·C(8)H(6)O(4), the asymmetric unit contains two halves of 1,2-bis-(4-pyrid-yl)ethene (bpe) mol-ecules and one benzene-1,3-dicarb-oxy-lic acid (1,3-H(2)BDC) mol-ecule. These bpe and 1,3-H(2)BDC mol-ecules are linked by classical O-H⋯N hydrogen bonds, forming an extended one-dimensional zigzag chain. Each chain is further linked with neighboring ones by π-π inter-actions between the pyridine and aromatic rings [centroid-centroid distances = 3.9306 (15) Å] and the pyridine rings of pairs of symmetry-related mol-ecules [centroid-centroid distances = 3.5751 (15), 3.7350 (15) and 3.6882 (15) Å], with the formation of a three-dimensional supra-molecular framework.

catena-Poly[[[bis-(4-bromo-benzoato-κO)zinc]-µ-1,2-bis-(4-pyrid-yl)ethene-κN:N'] acetonitrile monosolvate].

In the title coordination compound, {[Zn(C(7)H(4)BrO(2))(2)(C(12)H(10)N(2))]·CH(3)CN}(n), the Zn(II) atom is four-coordinated in a distorted tetra-hedral environment by two carboxyl-ate O atoms from two different 4-bromo-benzoate (bpe) ligands and two N atoms from two symmetry-related 1,2-bis-(4-pyrid-yl)ethene ligands. The Zn(II) atoms are bridged by the bpe ligands, which lie across centres of inversion, forming a zigzag chain along [001]. The void space of each unit cell is occupied by an acetonitrile solvent mol-ecule, which is connected to the complex mol-ecule by a weak C-H⋯N hydrogen bond.

The complete chloroplast genome and phylogenetic analysis of Corydalis fangshanensis W.T. Wang ex S.Y. He (Papaveraceae).

The complete chloroplast (cp) genome of Corydalis fangshanensis W.T. Wang ex S.Y. He, a Chinese endemic plant with limestone-specific distribution was first reported. The cp genome was circular in structure and 192,554 bp in length, consisting of a large single copy region (LSC, 98,393 bp), two inverted repeat regions (IRs, 42,263 bp), and a small single copy region (SSC, 9,635 bp). The overall GC content of the genome was 40.26%. It encoded 112 unique genes, including 78 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis resolved C. fangshanensis was closely related to C. saxicola G.S. Bunting within Corydalis sect. Thalictrifoliae (Fedde) Lidén, in line with morphological character-based taxonomy. Our result provides informative data for studying the taxonomy, phylogeny and ecology of Corydalis, especially species with specific-limestone distribution and also for studying the adaptive evolution in plants.

Gallium Porphyrin and Gallium Nitrate Reduce the High Vancomycin Tolerance of MRSA Biofilms by Promoting Extracellular DNA-Dependent Biofilm Dispersion.

Biofilms, structured communities of bacterial cells embedded in a self-produced extracellular matrix (ECM) which consists of proteins, polysaccharide intercellular adhesins (PIAs), and extracellular DNA (eDNA), play a key role in clinical infections and are associated with an increased morbidity and mortality by protecting the embedded bacteria against drug and immune response. The high levels of antibiotic tolerance render classical antibiotic therapies impractical for biofilm-related infections. Thus, novel drugs and strategies are required to reduce biofilm tolerance and eliminate biofilm-protected bacteria. Here, we showed that gallium, an iron mimetic metal, can lead to nutritional iron starvation and act as dispersal agent triggering the reconstruction and dispersion of mature methicillin-resistant Staphylococcus aureus (MRSA) biofilms in an eDNA-dependent manner. The extracellular matrix, along with the integral bacteria themselves, establishes the integrated three-dimensional structure of the mature biofilm. The structures and compositions of gallium-treated mature biofilms differed from those of natural or antibiotic-survived mature biofilms but were similar to those of immature biofilms. Similar to immature biofilms, gallium-treated biofilms had lower levels of antibiotic tolerance, and our in vitro tests showed that treatment with gallium agents reduced the antibiotic tolerance of mature MRSA biofilms. Thus, the sequential administration of gallium agents (gallium porphyrin and gallium nitrate) and relatively low concentrations of vancomycin (16 mg/L) effectively eliminated mature MRSA biofilms and eradicated biofilm-enclosed bacteria within 1 week. Our results suggested that gallium agents may represent a potential treatment for refractory biofilm-related infections, such as prosthetic joint infections (PJI) and osteomyelitis, and provide a novel basis for future biofilm treatments based on the disruption of normal biofilm-development processes.

NaCl-altered oxygen flux profiles and H+-ATPase activity in roots of two contrasting poplar species.

Maintaining mitochondrial respiration is crucial for proving ATP for H+ pumps to continuously exclude Na+ under salt stress. NaCl-altered O2 uptake, mitochondrial respiration and the relevance to H+-ATPase activity were investigated in two contrasting poplar species, Populus euphratica (salt-tolerant) and Populus popularis 35-44 (salt-sensitive). Compared with P. popularis, P. euphratica roots exhibited a greater capacity to extrude Na+ under NaCl stress (150 mM). The cytochemical analysis with Pb(NO3)2 staining revealed that P. euphratica root cells retained higher H+ hydrolysis activity than the salt-sensitive poplar during a long term (LT) of increasing salt stress (50-200 mM NaCl, 4 weeks). Long-sustained activation of proton pumps requires long-lasting supply of energy (adenosine triphosphate, ATP), which is delivered by aerobic respiration. Taking advantage of the vibrating-electrodes technology combined with the use of membrane-tipped, polarographic oxygen microelectrodes, the species, spatial and temporal differences in root O2 uptake were characterized under conditions of salt stress. Oxygen uptake upon NaCl shock (150 mM) was less declined in P. euphratica than in P. popularis, although the salt-induced transient kinetics were distinct from the drastic drop of O2 caused by hyperosmotic shock (255 mM mannitol). Short-term (ST) treatment (150 mM NaCl, 24 h) stimulated O2 influx in P. euphratica roots, and LT-treated P. euphratica displayed an increased O2 influx along the root axis, whereas O2 influx declined with increasing salinity in P. popularis roots. The spatial localization of O2 influxes revealed that the apical zone was more susceptible than the elongation region upon high NaCl (150, 200 mM) during ST and LT stress. Pharmacological experiments showed that the Na+ extrusion and H+-ATPase activity in salinized roots were correspondingly suppressed when O2 uptake was inhibited by a mitochondrial respiration inhibitor, NaN3. Therefore, we conclude that the stable mitochondrial respiration energized H+-ATPase of P. euphratica root cells for maintaining Na+ homeostasis under salt environments.

Reversible single-crystal-to-single-crystal conversion of a photoreactive coordination network for rewritable optical memory storage.

Reversible single-crystal-to-single-crystal photocyclization-cycloreversion reaction of a stilbene-based coordination network exhibits a conspicuous fluorescence change. The controllable fluorescence and high fatigue resistance feature of this bistable material make it a single-crystalline device for applications in rewritable optical memory storage systems.

Calcium mediates root K+/Na+ homeostasis in poplar species differing in salt tolerance.

Using the non-invasively ion-selective microelectrode technique, flux profiles of K(+), Na(+) and H(+) in mature roots and apical regions, and the effects of Ca(2+) on ion fluxes were investigated in salt-tolerant poplar species, Populus euphratica Oliver and salt-sensitive Populus simonii x (P. pyramidalis + Salix matsudana) (Populus popularis 35-44, P. popularis). Compared to P. popularis, P. euphratica roots exhibited a greater capacity to retain K(+) after exposure to a salt shock (SS, 100 mM NaCl) and a long-term (LT) salinity (50 mM NaCl, 3 weeks). Salt shock-induced K(+) efflux in the two species was markedly restricted by K(+) channel blocker, tetraethylammonium chloride, but enhanced by sodium orthovanadate, the inhibitor of plasma membrane (PM) H(+)-ATPase, suggesting that the K(+) efflux is mediated by depolarization-activated (DA) channels, e.g., KORCs (outward rectifying K(+) channels) and NSCCs (non-selective cation channels). Populus euphratica roots were more effective to exclude Na(+) than P. popularis in an LT experiment, resulting from the Na(+)/H(+) antiport across the PM. Moreover, pharmacological evidence implies that the greater ability to control K(+)/Na(+) homeostasis in salinized P. euphratica roots is associated with the higher H(+)-pumping activity, which provides an electrochemical H(+) gradient for Na(+)/H(+) exchange and simultaneously decreases the NaCl-induced depolarization of PM, thus reducing Na(+) influx via NSCCs and K(+) efflux through DA-KORCs and DA-NSCCs. Ca(2+) application markedly limited salt-induced K(+) efflux but enhanced the apparent Na(+) efflux, thus enabling the two species, especially the salt-sensitive poplar, to retain K(+)/Na(+) homeostasis in roots exposed to prolonged NaCl treatment.

Regioselective Photochemical Cycloaddition Reactions of Diolefinic Ligands in Coordination Polymers.

The pure diolefinic ligand 1,4-bis(pyridin-4-yl)-1,3-butadiene (bpbde) is photostable in the crystalline state. With the assistance of coordination-driven metal-organic assemblies, the photoreactivity of this diolefinic ligand can be significantly enhanced. A hydrothermal reaction of bpbde with Cd(NO3 )2 ⋅4 H2 O and the auxiliary ligand adipic acid resulted in the formation of a two-dimensional photoreactive coordination polymer (CP), [Cd(adipate)(bpbde)]n (1). When the aliphatic carboxylic acid was replaced by pimelic acid, another photoreactive CP [Cd(pimelate)(bpbde)]n (2) with a three-dimensional framework was obtained. With irradiation of 365 nm UV light, the bpbde ligands in crystalline 1 and 2 underwent a regioselective photochemical [2+2] cycloaddition reaction and converted to 3,4,7,8-tetra(pyridin-4-yl)tricyclo[4.2.0.02,5 ]octane (tptco) and 1,3-bis(pyridin-4-yl)-2,4-bis(2-(pyridin-4-yl)vinyl)cyclobutane (bpbpvcb), respectively. The results provide an interesting insight into the rational design of highly regio- or stereoselective photocatalytic reactions for the formation of special organic molecules.

Covalent switching, involving divinylbenzene ligands within 3D coordination polymers, indicated by changes in fluorescence.

Reversible cycloaddition reactions between 1,4-bis[2-(3-pyridyl)ethenyl]benzene and its photodimers were performed within a pair of three-dimensional coordination polymers with retention of single crystal character. In each case, switching between two crystalline forms could be followed by monitoring the flourescence behaviour.