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Background: Reports on CT-guided percutaneous drainage within the intervertebral space for pyogenic spondylodiscitis with a secondary psoas abscess are limited. Purpose: To evaluate CT-guided percutaneous drainage within the intervertebral space for pyogenic spondylodiscitis and a secondary psoas abscess in which the two sites appear to communicate. Material and Methods: Eight patients with pyogenic spondylodiscitis and a secondary psoas abscess showing communication with the intradiscal abscess underwent CT-guided percutaneous drainage within the intervertebral space. The clinical outcome was retrospectively assessed. Results: An 8-French pigtail catheter within the intervertebral space was successfully placed in all patients. Seven patients responded well to this treatment. The one remaining patient who had developed septic shock before the procedure died on the following day. The mean duration of drainage was 32 days (13-70 days). Only one patient with persistent back pain underwent surgery for stabilization of the spine after the improvement of inflammation. Among seven patients responding well, long-term follow-up (91-801 days, mean 292 days) was conducted in six patients excluding one patient who died of asphyxiation due to aspiration unrelated to the procedure within 30 days after the procedure. In these six patients, no recurrence of either pyogenic spondylodiscitis or the psoas abscess was noted. Conclusion: CT-guided percutaneous drainage within the intervertebral space can be effective for patients with pyogenic spondylodiscitis and a secondary psoas abscess if the psoas abscess communicates with the intradiscal abscess. [ABSTRACT FROM AUTHOR]

Abstract Background MUC5AC is a secretory mucin normally expressed in the surface muconous cells of stomach and bronchial tract. It has been known that MUC5AC de novo expression occurred in the invasive ductal carcinoma and pancreatic intraepithelial neoplasm with no detectable expression in normal pancreas, however, its function remains uncertain. Here, we report the impact of MUC5AC on the adhesive and invasive ability of pancreatic cancer cells. Methods We used two MUC5AC expressing cell lines derived from human pancreatic cancer, SW1990 and BxPC3. Small-interfering (si) RNA directed against MUC5AC were used to assess the effects of MUC5AC on invasion and adhesion of pancreas cancer cells in vitro and in vivo. We compared parental cells (SW1990 and BxPC3) with MUC5AC suppressed cells by si RNA (si-SW1990 and si-BxPC3). Results MUC5AC was found to express in more than 80% of pancreatic ductal carcinoma specimens. Next we observed that both of si-SW1990 and si-BxPC3 showed significantly lower adhesion and invasion to extracellular matrix components compared with parental cell lines. Expression of genes associated with adhesion and invasion including several integerins, matrix metalloproteinase (MMP) -3 and vascular endothelial growth factor (VEGF) were down-regulated in both MUC5AC suppressed cells. Furthermore, production of VEGF and phosphorylation of VEGFR-1 were significantly reduced by MUC5AC down regulation. Both of si-SW1990 and si-BxPC3 attenuated activation of Erk1/2. In vivo, si-SW1990 did not establish subcutaneous tumor in nude mice. Conclusions Knockdown of MUC5AC reduced the ability of pancreatic cancer cells to adhesion and invasion, suggesting that MUC5AC might contribute to the invasive motility of pancreatic cancer cells by enhancing the expression of integrins, MMP-3, VEGF and activating Erk pathway.

Atomically precise Ag nanoclusters display distinctive properties that are dictated by their structures and electronic states. However, manipulating the electronic states of Ag nanoclusters is challenging owing to their inherent instability and susceptibility to undesired structural changes, decomposition, and aggregation. Recently, we reported the synthesis of a body-centered cubic {Ag 30 } 22+ nanocluster encapsulated within a ring-shaped polyoxometalate (POM) [P 8 W 48 O 184 ] 40- by reacting 16 Ag + -containing [P 8 W 48 O 184 ] 40- with Ag + using N , N -dimethylformamide (DMF) as a mild reducing agent. This led to a redox-induced structural transformation into a face-centered cubic {Ag 30 } 16+ nanocluster. In this study, we demonstrated the modulation of the electronic states of Ag 30 nanoclusters within the ring-shaped POM through two different approaches. A face-centered cubic {Ag 30 } 18+ nanocluster, featuring distinct oxidation states compared to previously reported {Ag 30 } 22+ and {Ag 30 } 16+ nanoclusters, was synthesized using tetra- n -butylammonium borohydride, a stronger reducing agent than DMF, in the reaction of 16 Ag + -containing [P 8 W 48 O 184 ] 40- and Ag + . Additionally, by leveraging the acid-base properties of POMs, we demonstrated the reversible, stepwise modulation of the charge distribution in the Ag 30 nanocluster through controlling protonation states of the ring-shaped POM ligand. These results highlight the potential of engineering POM-stabilized Ag nanoclusters with diverse structures and electronic states, thereby facilitating the exploration of novel properties and applications utilizing the unique characteristics of the POM ligands.

Alloying is an effective method for modulating metal nanoclusters to enrich their structural diversity and physicochemical properties. Recent investigations have demonstrated that polyoxometalates (POMs) can act as effective multidentate ligands for silver (Ag) nanoclusters to endow them with synergistic properties, reactivity, catalytic properties, and stability. However, the application of POMs as ligands has been confined predominantly to monometallic nanoclusters. Herein, we report a synthetic method for fabricating surface-exposed gold (Au)-Ag alloy nanoclusters within a ring-shaped POM ([P 8 W 48 O 184 ] 40- ). Reacting an Ag nanocluster stabilized by the ring-shaped POM with Au ions (Au + ) was found to substitute several Ag atoms at the core of the nanocluster with Au atoms. The resultant {Au 8 Ag 26 } alloy nanocluster demonstrated superior photocatalytic activity and stability compared to the pristine Ag nanocluster in the aerobic oxidation of α-terpinene under visible-light irradiation. These findings provide fundamental insights into the formation and catalytic properties of POM-stabilized alloy nanoclusters and advance exploration into the synthesis and applications of diverse metal nanoclusters., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The high temperature requirement for the desorption of absorbed CO 2 is one of the issues for the widespread use of direct air capture (DAC), which is a promising technology to reduce atmospheric CO 2 concentration. This work realized a liquid diamine absorbent-solid carbamic acid (CA) phase-change DAC system with CO 2 desorption at a low temperature by using a MeOH solvent. The CA of isophoronediamine [3-(aminomethyl)-3,5,5-trimethylcyclohexylamine, CA-IPDA] readily desorbed CO 2 in MeOH at 50 °C, while IPDA showed the capacity to absorb low-concentration CO 2 from air with an IPDA/CO 2 ratio of 1:1. The CA-IPDA desorbed more than half of the absorbed CO 2 at 60 °C without any gas flow, proving that this system can condense low-concentration CO 2 in air to pure CO 2 with low energy requirements. The low-temperature desorption of CO 2 from CA-IPDA was owing to the high solubility of CA-IPDA in MeOH and the easy CO 2 transfer between carbamic acid and MeOH to form methyl carbonate ions. This solubility control in the liquid-solid phase-change system opens up the low-energy DAC systems., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Cu nanoclusters exhibit distinctive physicochemical properties and hold significant potential for multifaceted applications. Although Cu nanoclusters are synthesized by reacting Cu ions and reducing agents by covering their surfaces using organic protecting ligands or supporting them inside porous materials, the synthesis of surface-exposed Cu nanoclusters with a controlled number of Cu atoms remains challenging. This study presents a solid-state reduction method for the synthesis of Cu nanoclusters employing a ring-shaped polyoxometalate (POM) as a structurally defined and rigid molecular nanoreactor. Through the reduction of Cu 2+ incorporated within the cavity of a ring-shaped POM using H 2 at 140 °C, spectroscopic studies and single-crystal X-ray diffraction analysis revealed the formation of surface-exposed Cu nanoclusters with a defined number of Cu atoms within the cavities of POMs. Furthermore, the Cu nanoclusters underwent a reversible redox transformation within the cavity upon alternating the gas atmosphere (i.e., H 2 or O 2 ). These Cu nanoclusters produced active hydrogen species that can efficiently hydrogenate various functional groups such as alkenes, alkynes, carbonyls, and nitro groups using H 2 as a reductant. We expect that this synthesis approach will facilitate the development of a wide variety of metal nanoclusters with high reactivity and unexplored properties.

Here, doubly protonated Lindqvist-type niobium oxide cluster [H 2 (Nb 6 O 19 )] 6- , fabricated by microwave-assisted hydrothermal synthesis, exhibited superbase catalysis for Knoevenagel and crossed aldol condensation reactions accompanied by activating C-H bond with pK a >26 and proton abstraction from a base indicator with pK a =26.5. Surprisingly, [H 2 (Nb 6 O 19 )] 6- exhibited water-tolerant superbase properties for Knoevenagel and crossed aldol condensation reactions in the presence of water, although it is well known that the strong basicity of metal oxides and organic superbase is typically lost by the adsorption of water. Density functional theory calculation revealed that the basic surface oxygens that share the corner of NbO 6 units in [H 2 (Nb 6 O 19 )] 8- maintained the negative charges even after proton adsorption. This proton capacity and the presence of un-protonated basic sites led to the water tolerance of the superbase catalysis., (© 2024 Wiley‐VCH GmbH.)

Direct oral anticoagulants (DOACs) have been shown to be effective and safe in preventing pulmonary embolism recurrence. In this single-center retrospective observational study, we aimed to evaluate the efficacy and safety of reduced-dose DOACs in 86 consecutive patients with acute pulmonary embolism. Patients were divided into standard-dose and reduced-dose DOACs groups. Initial clot volume did not significantly differ between the two groups (standard-dose DOACs vs. reduced-dose DOACs, 18.8 [Q1-Q3 7.3-30.8] mL vs. 10.0 [Q1-Q3 3.2-27.9] mL, p = 0.1). Follow-up computed tomography (CT) within 30 days showed a higher rate of clot volume reduction or disappearance in the standard-dose group compared to the reduced-dose group (standard-dose DOACs vs. reduced-dose DOACs, 81.6% vs. 53.9%, p = 0.02). However, at the final follow-up CT, there was no significant difference in clot volume change between the two groups (standard-dose DOACs vs. reduced-dose DOACs, 91.5% vs. 82.0%, p = 0.19). Major bleeding occurred in two patients in the standard-dose group (4.3%) and three patients in the reduced-dose DOACs group (7.7%) (p = 0.5). In conclusion, while standard-dose DOACs demonstrated superior efficacy in early clot reduction, reduced doses of apixaban and edoxaban showed comparable efficacy and safety profiles in long-term treatment of acute pulmonary embolism in certain patients., (© 2024. The Author(s).)

Owing to their remarkable properties, gold nanoparticles are applied in diverse fields, including catalysis, electronics, energy conversion and sensors. However, for catalytic applications of colloidal gold nanoparticles, the trade-off between their reactivity and stability is a significant concern. Here we report a universal approach for preparing stable and reactive colloidal small (~3 nm) gold nanoparticles by using multi-dentate polyoxometalates as protecting agents in non-polar solvents. These nanoparticles exhibit exceptional stability even under conditions of high concentration, long-term storage, heating and addition of bases. Moreover, they display excellent catalytic performance in various oxidation reactions of organic substrates using molecular oxygen as the sole oxidant. Our findings highlight the ability of inorganic multi-dentate ligands with structural stability and robust steric and electronic effects to confer stability and reactivity upon gold nanoparticles. This approach can be extended to prepare metal nanoparticles other than gold, enabling the design of novel nanomaterials with promising applications., (© 2024. The Author(s).)

Single metal atoms supported on silica are attractive catalysts, and precise control of the local environment around the metal species is essential. Crystalline silica is useful as an efficient support for the incorporation of well-defined metal sites. Dimethyltin species were regularly grafted onto the layer surfaces of layered octosilicate, a type of two-dimensional (2D) crystalline silica. Dimethyltin dichlorides react with the surface silanol (SiOH) groups of the silicate layers. The formation of Si-O-Sn bonds was confirmed by 29 Si magic-angle spinning (MAS) NMR. X-ray absorption fine structure (XAFS) analysis showed the four-coordinated Sn species. These results suggested the presence of well-defined dipodal dimethyltin species on the layer surfaces. The degree of modification of the silanol groups with the dimethyltin groups increased with increasing amounts of dimethyltin dichloride; however, the maximum degree of modification was approximately 50%. This value was interpreted as an alternate modification of the octosilicate reaction sites with dimethyltin groups. These results demonstrate the potential for developing highly active single metal catalysts with a high density of regularly arranged active sites on high surface area supports.

Synthetic strategies to access high-valent iridium complexes usually require use of π donating ligands bearing electronegative atoms (e. g. amide or oxide) or σ donating electropositive atoms (e. g. boryl or hydride). Besides the η 5 -(methyl)cyclopentadienyl derivatives, high-valent η 1 carbon-ligated iridium complexes are challenging to synthesize. To meet this challenge, this work reports the oxidation behavior of an all-carbon-ligated anionic bis(CCC-pincer) Ir III complex. Being both σ and π donating, the diaryl dipyrido-annulated N-heterocyclic carbene (dpa-NHC) Ir III complex allowed a stepwise 4e - oxidation sequence. The first 2e - oxidation led to an oxidative coupling of two adjacent aryl groups, resulting in formation of a cationic chiral Ir III complex bearing a CCCC-tetradentate ligand. A further 2e - oxidation allowed isolation of a high-valent tricationic complex with a triplet ground state. These results close a synthetic gap for carbon-ligated iridium complexes and demonstrate the electronic tuning potential of organic π ligands for unusual electronic properties., (© 2023 Wiley-VCH GmbH.)

Although deuterium incorporation into pharmaceutical drugs is an attractive way to expand drug modalities, their physicochemical properties have not been sufficiently examined. This study focuses on examining the changes in physicochemical properties between flurbiprofen (FP) and flurbiprofen- d 8 (FP- d 8 ), which was successfully prepared by direct and multiple H/D exchange reactions at the eight aromatic C-H bonds of FP. Although the effect of deuterium incorporation was not observed between the crystal structures of FP and FP- d 8 , the melting point and heat of fusion of FP- d 8 were lower than those of FP. Additionally, the solubility of FP- d 8 increased by 2-fold compared to that of FP. Calculation of the interaction energy between FP/FP- d 8 and water molecules using the multi-component density functional theory method resulted in increased solubility of FP- d 8 . These novel and valuable findings regarding the changes in physicochemical properties triggered by deuterium incorporation can contribute to the further development of deuterated drugs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Iron-based heterogeneous catalysts are ideal metal catalysts owing to their abundance and low-toxicity. However, conventional iron nanoparticle catalysts exhibit extremely low activity in liquid-phase reactions and lack air stability. Previous attempts to encapsulate iron nanoparticles in shell materials toward air stability improvement were offset by the low activity of the iron nanoparticles. To overcome the trade-off between activity and stability in conventional iron nanoparticle catalysts, we developed air-stable iron phosphide nanocrystal catalysts. The iron phosphide nanocrystal exhibits high activity for liquid-phase nitrile hydrogenation, whereas the conventional iron nanoparticles demonstrate no activity. Furthermore, the air stability of the iron phosphide nanocrystal allows facile immobilization on appropriate supports, wherein TiO 2 enhances the activity. The resulting TiO 2 -supported iron phosphide nanocrystal successfully converts various nitriles to primary amines and demonstrates high reusability. The development of air-stable and active iron phosphide nanocrystal catalysts significantly expands the application scope of iron catalysts., (© 2023. Springer Nature Limited.)

For the realization of a next-generation energy society, further improvement in the activity of water-splitting photocatalysts is essential. Platinum (Pt) is predicted to be the most effective cocatalyst for hydrogen evolution from water. However, when the number of active sites is increased by decreasing the particle size, the Pt cocatalyst is easily oxidized and thereby loses its activity. In this study, a method to load ultrafine, monodisperse, metallic Pt nanoclusters (NCs) on graphitic carbon nitride is developed, which is a promising visible-light-driven photocatalyst. In this photocatalyst, a part of the surface of the Pt NCs is protected by sulfur atoms, preventing oxidation. Consequently, the hydrogen-evolution activity per loading weight of Pt cocatalyst is significantly improved, 53 times, compared with that of a Pt-cocatalyst loaded photocatalyst by the conventional method. The developed method is also effective to enhance the overall water-splitting activity of other advanced photocatalysts such as SrTiO 3 and BaLa 4 Ti 4 O 15 ., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)