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1.
Nano Lett ; 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39172732

ABSTRACT

An advanced materials solution utilizing the concept of "smart catalysts" could be a game changer for today's automotive emission control technology, enabling the efficient use of precious metals via their two-way switching between metallic nanoparticle forms and ionic states in the host perovskite lattice as a result of the cyclical oxidizing/reducing atmospheres. However, direct evidence for such processes remains scarce; therefore, the underlying mechanism has been an unsettled debate. Here, we use advanced scanning transmission electron microscopy to reveal the atomic-scale behaviors for a LaFe0.95Pd0.05O3-supported Ir-Pd-Ru nanocatalyst under fluctuating redox conditions, thereby proving the reversible dissolution/exsolution for Ir and Ru but with a limited occurrence for Pd. Despite such selective dissolution during oxidation, all three elements remain cooperatively alloyed in the subsequent reduction, which is a key factor in preserving the catalytic activity of the ternary nanoalloy while displaying its self-regenerating functionality and control of particle agglomeration.

2.
Int J Mol Sci ; 25(15)2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39125638

ABSTRACT

The oxidation of tetraselenatetracene (TSeT) by tetracyanoquinodimethane in the presence of dysprosium(III) tris(hexafluoroacetylacetonate), DyIII(hfac)3, produces black crystals of {TSeT1.5}●+[DyIII(hfac)4]- (1) salt, which combines conducting and magnetic sublattices. It contains one-dimensional stacks composed of partially oxidized TSeT molecules (formal averaged charge is +2/3). Dimers and monomers can be outlined within these stacks with charge and spin density redistribution. The spin triplet state of the dimers is populated above 128 K with an estimated singlet-triplet energy gap of 542 K, whereas spins localized on the monomers show paramagnetic behavior. A semiconducting behavior is observed for 1 with the activation energy of 91 meV (measured by the four-probe technique for an oriented single crystal). The DyIII ions coordinate four hfac- anions in [DyIII(hfac)4]-, providing D2d symmetry. Slow magnetic relaxation is observed for DyIII under an applied static magnetic field of 1000 Oe, and 1 is a single-ion magnet (SIM) with spin reversal barrier Ueff = 40.2 K and magnetic hysteresis at 2 K. Contributions from DyIII and TSeT●+ paramagnetic species are seen in EPR. The DyIII ion rarely manifests EPR signals, but such signal is observed in 1. It appears due to narrowing below 30 K and has g4 = 6.1871 and g5 = 2.1778 at 5.4 K.


Subject(s)
Dysprosium , Semiconductors , Dysprosium/chemistry , Anions/chemistry , Dimerization , Models, Molecular , Magnetic Phenomena , Magnetics
3.
J Hepatobiliary Pancreat Sci ; 31(7): 468-480, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38953871

ABSTRACT

PURPOSE: To describe the real-world treatment patterns of systemic therapies for biliary tract cancer (BTC) and to examine the frequency and management of biliary infection in Japan. METHODS: Patients diagnosed with BTC and prescribed systemic therapy between January 2011 and September 2020 were retrieved from the Japanese Medical Data Vision database. The look-back period was set to 5 years. Patient characteristics, treatment patterns, and biliary infection-induced treatment interruption were analyzed. RESULTS: The full analysis set comprised 22 742 patients with a mean age of 71.0 years and 61.6% were male. The most common BTC type was extrahepatic cholangiocarcinoma (44.6%). The three most common first-line regimens were S-1 monotherapy (33.0%), gemcitabine+cisplatin (32.5%), and gemcitabine monotherapy (18.7%) over the entire observation period (January 2011-September 2021). Patients who received monotherapies tended to be older. Biliary infection-induced treatment interruption occurred in 29.5% of patients, with a median time to onset of 64.0 (interquartile range 29.0-145.0) days. The median duration of intravenous antibiotics was 12.0 (interquartile range 4.0-92.0) days. CONCLUSIONS: These results demonstrated potential challenges of BTC in Japanese clinical practice particularly use of multiple regimens, commonly monotherapies, which are not recommended as first-line treatment, and the management of biliary infections during systemic therapy.


Subject(s)
Biliary Tract Neoplasms , Databases, Factual , Humans , Male , Female , Aged , Japan , Biliary Tract Neoplasms/drug therapy , Middle Aged , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Deoxycytidine/administration & dosage , Gemcitabine , Tegafur/administration & dosage , Tegafur/therapeutic use , Retrospective Studies , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Drug Combinations , Cisplatin/therapeutic use , Cisplatin/administration & dosage , Oxonic Acid/administration & dosage , Oxonic Acid/therapeutic use , Practice Patterns, Physicians'/statistics & numerical data
4.
Chem Sci ; 15(25): 9641-9648, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38939130

ABSTRACT

Exploration of porous adsorbents with high CO2/N2 selectivity is of great significance for reducing CO2 content in the atmosphere. In this study, a series of isoreticular ultramicroporous fluorinated metal-organic frameworks (MOFs) were prepared to explore the benefits of fluorinated ultramicropores in improving CO2/N2 selectivity. Gas adsorption measurements revealed that the increase in the number of fluorine atoms in a ligand molecule leads to the increased CO2 uptakes and CO2/N2 selectivity. Theoretical calculations indicate that the interaction between the fluorine atoms and adsorbed CO2 molecules enhances the CO2-philicity, offering useful insight into the improvement of CO2/N2 selectivity in isoreticular frameworks.

5.
Thorac Cancer ; 15(20): 1541-1552, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38812106

ABSTRACT

BACKGROUND: To elucidate the treatment and surgery outcomes with or without perioperative therapies in Japanese patients with clinical stage III non-small cell lung cancer (NSCLC) in real-world settings. METHODS: We performed subset analyses of the SOLUTION study, a multicenter, noninterventional, observational study of Japanese patients diagnosed with clinical stage III NSCLC, for those who started first-line treatment (surgery±perioperative therapy) between January 2013 and December 2014 (study registration: UMIN000031385). Follow-up data were obtained using medical records from diagnosis to March 1, 2018. RESULTS: Of 149 eligible patients, 67 underwent surgery alone (median age 71 years) and 82 underwent surgery+perioperative therapy (median age 63 years). Lung resection was performed in 137 patients and the others underwent exploratory thoracotomy or other procedures. Perioperative therapies included adjuvant therapy only (n = 41), neoadjuvant therapy only (n = 24), and neoadjuvant+adjuvant therapy (n = 17). The median overall survival (OS) and 3-year OS rate were 29.3 months and 44.0%, respectively, in patients who underwent surgery alone, and not reached and 61.1%, respectively, in patients who underwent surgery+perioperative therapy. The 3-year progression-free survival (PFS) and disease-free survival (DFS) rates were 42.4% and 47.1%, respectively, in patients who underwent surgery+perioperative therapy and 28.5% and 28.9%, respectively, in patients who underwent surgery alone. In multivariable Cox regression, perioperative therapy was associated with improved OS (hazard ratio [95% confidence interval] 0.49 [0.29-0.81]), PFS (0.62 [0.39-0.96]), and DFS (0.62 [0.39-0.97]) versus surgery alone. CONCLUSIONS: Our study suggested that perioperative therapy may be associated with better survival among patients undergoing surgical treatment of clinical stage III NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Neoplasm Staging , Humans , Carcinoma, Non-Small-Cell Lung/surgery , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/mortality , Female , Male , Lung Neoplasms/surgery , Lung Neoplasms/pathology , Lung Neoplasms/mortality , Aged , Middle Aged , Japan , Treatment Outcome , Aged, 80 and over , Pneumonectomy/methods , Cohort Studies , Adult , East Asian People
6.
J Am Chem Soc ; 146(19): 12950-12957, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38693778

ABSTRACT

Metal-organic framework (MOF) glasses have emerged as a new class of organic-inorganic hybrid glass materials. Considerable efforts have been devoted to unraveling the macroscopic dynamics of MOF glasses by studying their rheological behavior; however, their microscopic dynamics remain unclear. In this work, we studied the effect of vitrification on linker dynamics in ZIF-62 by solid-state 2H nuclear magnetic resonance (NMR) spectroscopy. 2H NMR relaxation analysis provided a detailed picture of the mobility of the ZIF-62 linkers, including local restricted librations and a large-amplitude twist; these details were verified by molecular dynamics. A comparison of ZIF-62 crystals and glasses revealed that vitrification does not drastically affect the fast individual flipping motions with large-amplitude twists, whereas it facilitates slow cooperative large-amplitude twist motions with a decrease in the activation barrier. These observations support the findings of previous studies, indicating that glassy ZIF-62 retains permanent porosity and that short-range disorder exists in the alignment of ligands because of distortion of the coordination angle.

7.
Chem Sci ; 15(20): 7560-7567, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38784732

ABSTRACT

Solid-solution alloys based on platinum group metals and p-block metals have attracted much attention due to their promising potential as materials with a continuously fine-tunable electronic structure. Here, we report on the first synthesis of novel solid-solution RuSn alloy nanoparticles (NPs) by electrochemical cyclic voltammetry sweeping of RuSn@SnOx NPs. High-angle annular dark-field scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy maps confirmed the random and homogeneous distribution of Ru and Sn elements in the alloy NPs. Compared with monometallic Ru NPs, the RuSn alloy NPs showed improved hydrogen evolution reaction (HER) performance. The overpotentials of Ru0.94Sn0.06 NPs/C and Ru0.87Sn0.13 NPs/C to achieve a current density of 10 mA cm-2 were 43.41 and 33.19 mV, respectively, which are lower than those of monometallic Ru NPs/C (53.53 mV) and commercial Pt NPs/C (55.77 mV). The valence-band structures of the NPs investigated by hard X-ray photoelectron spectroscopy demonstrated that the d-band centre of RuSn NPs shifted downward compared with that of Ru NPs. X-ray photoelectron spectroscopy and X-ray absorption near-edge structure analyses indicated that in the RuSn alloy NPs, charge transfer occurs from Sn to Ru, which was considered to result in a downward shift of the d-band centre in RuSn NPs and to regulate the adsorption energy of intermediate Hads effectively, and thus enable the RuSn solid-solution alloy NPs to exhibit excellent HER catalytic properties.

8.
Nat Commun ; 15(1): 4514, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802491

ABSTRACT

Knowledge on the distribution and dynamics of glycosylation enzymes in the Golgi is essential for better understanding this modification. Here, using a combination of CRISPR/Cas9 knockin technology and super-resolution microscopy, we show that the Golgi complex is assembled by a number of small 'Golgi units' that have 1-3 µm in diameter. Each Golgi unit contains small domains of glycosylation enzymes which we call 'zones'. The zones of N- and O-glycosylation enzymes are colocalised. However, they are less colocalised with the zones of a glycosaminoglycan synthesizing enzyme. Golgi units change shapes dynamically and the zones of glycosylation enzymes rapidly move near the rim of the unit. Photobleaching analysis indicates that a glycosaminoglycan synthesizing enzyme moves between units. Depletion of giantin dissociates units and prevents the movement of glycosaminoglycan synthesizing enzymes, which leads to insufficient glycosaminoglycan synthesis. Thus, we show the structure-function relationship of the Golgi and its implications in human pathogenesis.


Subject(s)
Glycosaminoglycans , Golgi Apparatus , Golgi Apparatus/metabolism , Glycosylation , Humans , Glycosaminoglycans/metabolism , HeLa Cells , CRISPR-Cas Systems , Membrane Proteins/metabolism , Membrane Proteins/genetics , Golgi Matrix Proteins
9.
iScience ; 27(4): 109528, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38595797

ABSTRACT

Diabetic neuropathy (DN) is a major complication of diabetes mellitus. Chondroitin sulfate (CS) is one of the most important extracellular matrix components and is known to interact with various diffusible factors; however, its role in DN pathology has not been examined. Therefore, we generated CSGalNAc-T1 knockout (T1KO) mice, in which CS levels were reduced. We demonstrated that diabetic T1KO mice were much more resistant to DN than diabetic wild-type (WT) mice. We also found that interactions between pericytes and vascular endothelial cells were more stable in T1KO mice. Among the RNA-seq results, we focused on the transforming growth factor ß signaling pathway and found that the phosphorylation of Smad2/3 was less upregulated in T1KO mice than in WT mice under hyperglycemic conditions. Taken together, a reduction in CS level attenuates DN progression, indicating that CS is an important factor in DN pathogenesis.

11.
Phys Chem Chem Phys ; 26(18): 13675-13682, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38654606

ABSTRACT

In our preceding paper (Y. Fukui et al., Phys. Chem. Chem. Phys., 2023, 25, 25594-25602), we reported a systematic study of the Ag+-ion conducting behaviour of silver iodide (AgI)-loaded mesoporous aluminas (MPAs) with different pore diameters and AgI-loading ratios. By optimising the control parameters, the Ag+-ion conductivity has reached 7.2 × 10-4 S cm-1 at room temperature, which is more than three orders of magnitude higher than that of bulk AgI. In the present study, the effect of silver bromide (AgBr)-doping in the AgI/MPA composites on Ag+-ion conductivity is systematically investigated for the first time, using variable-temperature powder X-ray diffraction, differential scanning calorimetry, and electrochemical impedance spectroscopy measurements. The AgBr-doped AgI/MPA composites, AgI-AgBr/MPA, formed a homogeneous ß/γ-AgI-structured solid solution (ß/γ-AgIss) for the composites with AgBr ≤ 10 mol%, above which the composites underwent a phase separation into ß/γ-AgIss and face-centred cubic AgBr solid solutions (AgBrss). The onset temperature of the exothermic peaks attributed to the transition from α-AgI-structured solid-solution phase to ß/γ-AgIss or AgBrss decreased with increasing the AgBr-doping ratio. The room-temperature ionic conductivity of the AgI-AgBr/MPA composites exhibited a volcano-type dependence on the AgBr-doping ratio with the highest value (1.6 × 10-3 S cm-1) when the AgBr content was 10 mol%. This value is more than twice as high as that of the highest conducting AgI/MPA found in our previous study.

12.
Breast Cancer ; 31(4): 581-592, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38679657

ABSTRACT

BACKGROUND: Anthracycline- and taxane-based chemotherapy regimens are established treatments for human epidermal growth factor receptor (HER)2-negative early-stage breast cancer with high risk of recurrence. This study examined the prevalence of these chemotherapy regimens as perioperative therapy, the patterns of retreatment, and factors influencing prescription choices in Japan. METHODS: This observational cohort study focused on high-risk early-stage breast cancer patients not undergoing anti-HER2 therapy, utilizing data from a hospital-based claims database in Japan spanning from April 2008 to September 2021. RESULTS: Of 42,636 high-risk patients who underwent breast cancer surgery, 32,133 (75.4%) were categorized as having luminal-type (received endocrine therapy) and 10,503 (24.6%) as having triple-negative cancer (not receiving any endocrine therapies). Most patients (98.7%) with luminal-type breast cancer received perioperative therapy, and 40.3% of those received anthracycline/taxane. In the triple-negative group, 57.0% of all patients received perioperative therapy and of those, 93.4% received anthracycline/taxane. Being over 40 years old, having an early stage (clinical stage ≤ II), and receiving treatment in non-specialized facilities were associated with less use of anthracycline/taxane in the luminal-type group. For the triple-negative group, associated factors with less use of anthracycline/taxane included being over 60 years old, treatment in small hospital (capacity < 200 beds), and treatment in non-specialized facilities. CONCLUSIONS: Approximately half the patients in both the luminal-type and triple-negative groups were prescribed anthracycline and/or taxane for perioperative chemotherapy. The choice was associated with patient age, cancer stage, and the scale and specialization of the treatment facilities. This study sheds light on the current state of breast cancer treatment practices in Japan.


Subject(s)
Anthracyclines , Antineoplastic Combined Chemotherapy Protocols , Breast Neoplasms , Receptor, ErbB-2 , Taxoids , Humans , Female , Japan/epidemiology , Middle Aged , Anthracyclines/therapeutic use , Receptor, ErbB-2/metabolism , Adult , Taxoids/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Breast Neoplasms/metabolism , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bridged-Ring Compounds/therapeutic use , Neoplasm Staging , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Chemotherapy, Adjuvant/statistics & numerical data , Chemotherapy, Adjuvant/methods
13.
Nanoscale ; 16(19): 9311-9316, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38655766

ABSTRACT

The properties of solids could be largely affected by their crystal structures. We achieved, for the first time, the phase control of solid-solution RuIn nanoparticles (NPs) from face-centred cubic (fcc) to hexagonal close-packed (hcp) crystal structures by hydrogen heat treatment. The effect of the crystal structure of RuIn alloy NPs on the catalytic performance in the hydrogen evolution reaction (HER) was also investigated. In the hcp RuIn NPs, enhanced HER catalytic performance was observed compared to the fcc RuIn NPs and monometallic Ru NPs. The intrinsic electronic structures of the NPs were investigated by valence-band X-ray photoelectron spectroscopy (VB-XPS). The d-band centre of hcp RuIn NPs obtained from VB-XPS was deeper than that of fcc RuIn NPs and monometallic Ru NPs, which is considered to enable the hcp RuIn NPs to exhibit enhanced HER catalytic performance.

14.
Elife ; 122024 Mar 21.
Article in English | MEDLINE | ID: mdl-38512724

ABSTRACT

Radial neuronal migration is a key neurodevelopmental event for proper cortical laminar organization. The multipolar-to-bipolar transition, a critical step in establishing neuronal polarity during radial migration, occurs in the subplate/intermediate zone (SP/IZ), a distinct region of the embryonic cerebral cortex. It has been known that the extracellular matrix (ECM) molecules are enriched in the SP/IZ. However, the molecular constitution and functions of the ECM formed in this region remain poorly understood. Here, we identified neurocan (NCAN) as a major chondroitin sulfate proteoglycan in the mouse SP/IZ. NCAN binds to both radial glial-cell-derived tenascin-C (TNC) and hyaluronan (HA), a large linear polysaccharide, forming a ternary complex of NCAN, TNC, and HA in the SP/IZ. Developing cortical neurons make contact with the ternary complex during migration. The enzymatic or genetic disruption of the ternary complex impairs radial migration by suppressing the multipolar-to-bipolar transition. Furthermore, both TNC and NCAN promoted the morphological maturation of cortical neurons in vitro. The present results provide evidence for the cooperative role of neuron- and radial glial-cell-derived ECM molecules in cortical development.


Subject(s)
Extracellular Matrix , Neurons , Animals , Mice , Neurons/physiology , Extracellular Matrix/metabolism , Cerebral Cortex/metabolism , Cell Movement/physiology , Chondroitin Sulfate Proteoglycans/metabolism
15.
Inorg Chem ; 63(9): 4196-4203, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38377386

ABSTRACT

We report on a new organic conductor κ″-(ET)2Cu[N(CN)2]Br (κ″-Br), which is the first polymorph of an organic superconductor κ-(ET)2Cu[N(CN)2]Br (κ-Br), where ET denotes bis(ethylenedithio)tetrathiafulvalene. κ″-Br has a similar κ-type arrangement of ET molecules to κ-Br, but, in contrast to the orthorhombic κ-Br, which has ordered polyanion chains, presents a monoclinic crystal structure with disordered polymeric anion chains. To elucidate the electronic state of κ″-Br, we performed band calculations as well as transport, magnetic, and optical measurements. The calculated band dispersion, magnitude of electron correlation, and room-temperature optical conductivity spectra of κ″-Br were comparable to those of κ-Br. Despite these similarities, the κ″-Br salt exhibited a semiconducting behavior. The electron spin resonance and Raman spectroscopies indicated that there is neither magnetic nor charge order in κ″-Br, suggesting the occurrence of Anderson localization due to disordered anion layers.

16.
Angew Chem Int Ed Engl ; 63(14): e202400162, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38339815

ABSTRACT

Ladder systems situated in the dimensional crossover region have attracted much attention because their electronic states and physical properties depend strongly on the electronic correlations among the constituent legs. Generally, two-/three-legged transition metal-oxide ladder compounds are studied as representative ladder systems, but two-/three-dimensional (2D/3D) extensions based on such ladder systems with a few numbers of legs are difficult because of the extreme synthesis conditions. Here, for the first time, we report the successful creation of a 3D extended two-legged ladder compound, [Pt(en)(dpye)I]2(NO3)4 ⋅ 2H2O (en=ethylenediamine; dpye=1,2-Di(4-pyridyl)ethane), which is obtained by simple oxidative polymerization of a small Pt macrocyclic complex using elemental I2. The unique 3D extended lattice consists of 1D mixed-valence halogen-bridged metal chains (⋅⋅⋅Pt-I-Pt-I⋅⋅⋅) and helically arranged macrocyclic units as the constituent legs and rungs, as confirmed by single-crystal X-ray diffraction. Diffuse X-ray scattering analyses and optical measurements revealed that the out-of-phase mixed-valence Pt2+/Pt4+ arrangement arises from the weak interchain correlation among adjacent legs. In addition, this compound shows an increase in proton conductivity by a factor of up to 1000, depending on humidity.

17.
ACS Appl Mater Interfaces ; 16(7): 8984-8992, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38326087

ABSTRACT

Plasmonic Schottky devices have attracted considerable attention for use in practical applications based on photoelectric conversion, because they enable light to be harvested below the bandgap of semiconductors. In particular, silicon-based (Si) plasmonic Schottky devices have great potential for useful photodetection in the near-infrared region. However, the internal quantum efficiency (IQE) values of previously reported devices are low because the Schottky barrier is excessively high. Here, we are the first to develop AuAg nanoalloy-n-type Si plasmonic Schottky devices by cathodic arc plasma deposition. Interestingly, it is found that a novel nanostructure, which leads to the improvement of responsivities, is formed. Moreover, these plasmonic nanostructures can be fabricated in only ∼1 min. The fabricated AuAg nanoparticle-film structure enables proper control of the Schottky barrier height and increases the area of the Schottky interface for electron transfer. As a result, the considerably enhanced IQE of our device at a telecommunication wavelength of 1310 nm (1550 nm) without external bias is 4.6 (6.5) times higher than those in previous reports, and these responsivities are a record high. This approach can be applied to realize efficient photodetection in the NIR region and extend the use of light below the bandgap of semiconductors. This paves the way for future application advancements in a variety of fields, including photodetection, imaging, photovoltaics, and photochemistry.

18.
Dalton Trans ; 53(7): 3159-3166, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38240125

ABSTRACT

The interaction between photochromic 8-methoxy-1',3',3'-trimethyl-6-nitro-spiro[chromene-2,2'-indole] (MNSP) and cobalt(II) hexafluoroacetylacetonate yields a deep red-violet solution due to the coordination-induced transition of MNSP from a colorless closed state to a colored open merocyanine (MC) form. The resulting complex {CoII(hfac)2·MNSP} (1) is obtained as crystals, and its structure at 250 K shows the coordination of two oxygen atoms from MNSP with CoII, forming a distorted octahedral surrounding around CoII. The unit cell of 1 contracts below 170 K by 5.5%, which is accompanied by shortening O-Co bonds and altering O-Co-O angles in the structure solved at 150 K. The χMT value of 3.06 emu K mol-1 at 300 K indicates the formation of high-spin CoII (S = 3/2) with a large orbital contribution characteristic of the octahedral surrounding. The contraction of the unit cell of 1 below 170 K provides a reversible 2.2% change of χMT in the 170-160 K range during heating and cooling regimes without hysteresis. The electron paramagnetic resonance signal of 1 was simulated with g-values of gx = 2.342, gy = 2.364, and gz = 2.084, and an isotropic g-factor of 2.267. The temperature-dependent χMT and field-dependent magnetization of 1 allow us to determine a positive zero-field splitting parameter of +20.1 cm-1. A study of the dynamic properties of 1 shows slow magnetic relaxation for CoII in a static field of 1000 Oe. Magnetic hysteresis loops were observed for 1 at 0.5 and 2 K; these loops are closed in the zero field region but opened at fields higher than ±100 and 700 Oe, respectively. The collapse of the loop is observed at 5 K. Excitation of the solution of 1 with green light decreases partially the intensity of the bands of the complex, whereas subsequent exposure of this solution to UV light partially restores these intensities.

19.
Commun Biol ; 7(1): 129, 2024 01 25.
Article in English | MEDLINE | ID: mdl-38272969

ABSTRACT

Neudesin, originally identified as a neurotrophic factor, has primarily been studied for its neural functions despite its widespread expression. Using 8-week-old neudesin knockout mice, we elucidated the role of neudesin in the spleen. The absence of neudesin caused mild splenomegaly, shortened lifespan of circulating erythrocytes, and abnormal recovery from phenylhydrazine-induced acute anemia. Blood cross-transfusion and splenectomy experiments revealed that the shortened lifespan of erythrocytes was attributable to splenic impairment. Further analysis revealed increased erythrophagocytosis and decreased iron stores in the splenic red pulp, which was linked to the upregulation of Fcγ receptors and iron-recycling genes in neudesin-deficient macrophages. In vitro analysis confirmed that neudesin suppressed erythrophagocytosis and expression of Fcγ receptors through ERK1/2 activation in heme-stimulated macrophages. Finally, we observed that 24-week-old neudesin knockout mice exhibited severe symptoms of anemia. Collectively, our results suggest that neudesin regulates the function of red pulp macrophages and contributes to erythrocyte and iron homeostasis.


Subject(s)
Anemia , Iron , Animals , Mice , Iron/metabolism , Macrophages/metabolism , Mice, Knockout , Phagocytosis/physiology , Receptors, IgG/metabolism , Spleen/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Nerve Tissue Proteins/metabolism
20.
J Am Chem Soc ; 146(1): 181-186, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38153046

ABSTRACT

High-entropy oxide nanoparticles (HEO NPs) have been intensively studied because of their attractive properties, such as high stability and enhanced catalytic activity. In this work, for the first time, denary HEO NPs were successfully synthesized using a continuous supercritical hydrothermal flow process without calcination. Interestingly, this process allows the formation of HEO NPs on the order of seconds at a relatively lower temperature. The synthesized HEO NPs contained 10 metal elements, La, Ca, Sr, Ba, Fe, Mn, Co, Ru, Pd, and Ir, and had a perovskite-type structure. Atomic-resolution high-angle annular dark-field scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy measurements revealed homogeneous dispersion of the 10 metal elements. The obtained HEO NPs also exhibited a higher catalytic activity for the CO oxidation reaction than that of the LaFeO3 NPs.

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