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1.
J Colloid Interface Sci ; 678(Pt C): 754-765, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39307063

RESUMEN

A series of heterogeneous catalysts, designated as POP-n-Pd (where n = 1, 2, 3, or 4), were synthesized by polymerizing a six-membered N-heterocyclic compound with an alkyl substituted group monomer (S1), using divinylbenzene (DVB) as crosslinkers. This process was followed by the incorporation of palladium (Pd) nanoparticles. The impact of the substituted group and the S1:DVB ratio in the catalysts, together with the reaction conditions, was investigated to assess their influence on the catalytic performance in converting propylamine, carbon dioxide (CO2) and 4-iodoanisole to oxazolidinones. The POP-1-Pd catalyst, featuring a methyl substituted group and a S1:DVB ratio of 1:4, exhibited remarkable efficiency, resulting in an excellent yield of 96 % under room temperature and ambient pressure conditions. Furthermore, it has demonstrated wide applicability across a variety of substrates and in the treatment of lime kiln exhaust gas. Additionally, POP-1-Pd can be used in a gram-scale reaction and maintains its performance after six recycles, with no significant decline in yield. The possible catalytic mechanism is proposed as follows: the catalyst's pores adsorb both CO2 and substrates, creating a high concentration reactant enrichment microenvironment. This facilitates the activation of both CO2 and substrates by the imidazole moiety and Pd nanoparticles in the catalyst, thereby generating oxazolidinones.

2.
Gen Hosp Psychiatry ; 91: 25-32, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39260189

RESUMEN

OBJECTIVES: This study employed a national longitudinal cohort to assess expected years of life lost (EYLL) in newly diagnosed psychiatric patients. METHODS: Data from Taiwan's National Death Registry and Health Insurance Research Database were scrutinized to identify patients with various psychiatric disorders. Disorders were ranked hierarchically, and age groups were categorized as young, middle-aged, and older adults. We utilized the semiparametric survival extrapolation method to estimate life expectancy (LE) and EYLL. Modifying effect of comorbid conditions and socioeconomic characteristics were also explored. RESULTS: Among the 5,757,431 cases, young adults with dementia, alcohol use disorder, schizophrenia, and bipolar disorder experienced an excess of 15 years of EYLL. Middle-aged adults faced approximately 9 years or more of EYLL, while older adults had lower EYLL values. Comorbid conditions, low income levels, and living in rural areas were associated with higher EYLL. CONCLUSIONS: This study underscores the substantial EYLL among young adults with psychiatric disorders and the significant impact of specific disorders on EYLL. Early intervention, tailored support, and healthcare system readiness are imperative for improved outcomes. Resource allocation and targeted interventions focusing on early detection and comprehensive treatment can alleviate the economic burden.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39269425

RESUMEN

A novel multidimensional electromagnetic wave-absorbing material was developed by combining carboxylated carbon nanotubes (CNT) with graphene oxide (GO) through multidimensional design, and cobalt/nickel-based metal organic frameworks (Co/Ni-MOF) were subsequently loaded onto the GO surface via its rich functional groups to form the composite absorbing material CNT-rGO-Co/Ni-MOF. Incorporating 25 wt % of CNT-rGO-Co/Ni-MOF into the paraffin matrix led to a remarkable RLmin value of -43 dB at 16.4 GHz, with an effective absorbing bandwidth (EAB) exceeding 4 GHz, all within a thickness of just 1.5 mm, showcasing its "lightweight, broadband, and high efficiency" characteristics. The exceptional electromagnetic wave absorption performance was attributed to multi-interface polarization loss, resistance loss, and magnetic medium loss. Furthermore, when incorporating 10 wt % of CNT-rGO-Co/Ni-MOF, the heat release capacity and peak heat release rate of EP/CNT-rGO-Co/Ni-MOF10 decreased by 59.2 and 52.6%, respectively.

5.
Chem Commun (Camb) ; 60(75): 10394-10397, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39224062

RESUMEN

Compounds comprising S-S bonds serve as significant pharmacological scaffolds in medicinal chemistry and natural products. We have devised an efficient electrochemical method for the construction of asymmetric disulfide bonds, leading to the synthesis of unsymmetric thiosulfonates. Compared with existing synthesis methods, our work not only avoids the use of metals and oxidants, but also realizes the operation of a one-pot three-component method, which makes this strategy extremely attractive.

6.
Phys Rev Lett ; 133(9): 096702, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39270189

RESUMEN

The skyrmion crystal (SkX) and helix (HL) phases, present in typical chiral magnets, can each be considered as forms of density waves but with distinct topologies. The SkX exhibits gyrodynamics analogous to electrons under a magnetic field, while the HL state resembles topological trivial spin density waves. However, unlike the charge density waves, the theoretical analysis of the sliding motion of SkX and HL remains unclear, especially regarding the similarities and differences in sliding dynamics between these two spin density waves. In this Letter, we systematically explore the sliding dynamics of SkX and HL in chiral magnets in the limit of large current density. We demonstrate that the sliding dynamics of both SkX and HL can be unified within the same theoretical framework as density waves, despite their distinct microscopic orders. Furthermore, we highlight the significant role of gyrotropic sliding induced by impurity effects in the SkX state, underscoring the impact of nontrivial topology on the sliding motion of density waves. Our theoretical analysis shows that the effect of impurity pinning is much stronger in HL compared with SkX, i.e., χ^{SkX}/χ^{HL}∼α^{2} (χ^{SkX}, χ^{HL}: susceptibility to the impurity potential, α (≪1) is the Gilbert damping). Moreover, the velocity correction is mostly in the transverse direction to the current in SkX. These results are further substantiated by realistic Landau-Lifshitz-Gilbert simulations.

7.
Chemistry ; : e202402716, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167361

RESUMEN

Dithiocarbamate is a key structural sequence in pharmaceuticals and agrochemicals, and its synthesis is crucial in organic chemistry. Although significant progress has been made in related synthesis research, developing a practical and universal synthesis method remains fascinating. Herein, we report a new visible-light-induced decarboxylation coupling reaction between N-hydroxyphthalimide esters and tetraalkylthiuram disulfides, which uses Ir(ppy)3 as a photocatalyst to promote the generation of corresponding decarboxylation thioacylation product-dithiocarbamates in high yields. This redox-neutral protocol uses inexpensive and readily available starting material under mild reaction conditions, exhibiting broad substrate scope and wide functional group compatibility. This method can be further used for post modification of complex natural products and bioactive drugs.

8.
Phys Rev Lett ; 133(5): 056601, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159079

RESUMEN

Recent experiments reported that quantum Hall chiral edge state-mediated Josephson junctions (chiral Josephson junctions) could exhibit Fraunhofer oscillations with a periodicity of either h/e [Vignaud et al., Nature (London) 624, 545 (2023)NATUAS0028-083610.1038/s41586-023-06764-4] or h/2e [Amet et al., Science 352, 966 (2016)SCIEAS0036-807510.1126/science.aad6203]. While the h/e-periodic component of the supercurrent had been anticipated theoretically before, the emergence of the h/2e periodicity is still not fully understood. In this Letter, we systematically study the Fraunhofer oscillations of chiral Josephson junctions. In chiral Josephson junctions, the chiral edge states coupled to the superconductors become chiral Andreev edge states. We find that in short junctions, the coupling of the chiral Andreev edge states can trigger the h/2e-magnetic flux periodicity. Our theory resolves the important puzzle concerning the appearance of the h/2e periodicity in chiral Josephson junctions. Furthermore, we explain that when the chiral Andreev edge states couple, a pair of localized Majorana zero modes appear at the ends of the Josephson junction, which are robust and independent of the phase difference between the two superconductors. As the h/2e periodicity and the Majorana zero modes have the same physical origin in the wide junction limit, the Fraunhofer oscillation period could be useful in identifying the regime with Majorana zero modes.

9.
Chem Sci ; 15(34): 13779-13787, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39211500

RESUMEN

The manipulation of biocompatible supramolecular nanostructures at subcellular and cellular levels has become one of the increasingly significant topics but remains a formidable challenge in chemical and biological science. In this work, a controllable supramolecular aggregate based on host-guest competitive binding is elaborately constructed using cucurbit[8]uril, methionine-containing amphiphilic peptide, and perylene diimide, displaying in situ oxidation-driven macrocycle-confined fluorescence enhancement for cell imaging and morphological reconstruction for cancer cell death. The experimental results demonstrate that cucurbit[8]uril possesses a high binding affinity with the methionine peptide, while this value sharply decreases after the methionine residue is oxidized to sulfoxide or sulfone. Therefore, perylene diimide can be competitively included by cucurbit[8]uril in the co-assemblies, eventually resulting in a 10-fold fluorescence enhancement and the conversion of topological morphology from nano-sized particles to micron-sized sheets. Moreover, the obtained ternary assemblies can be oxidized by endogenous reactive oxygen species in cancer cells, thus not only providing enhanced fluorescence for cell imaging, but also leading to endoplasmic reticulum dysfunction and significant cell death. Therefore, the controllable and oxidation-responsive morphological transformation based on the host-guest competitive binding in biological media can be viewed as a feasible means for efficient disease theragnosis.

10.
Int J Mol Sci ; 25(15)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39125802

RESUMEN

The hair follicle is the basis of hair regeneration, and the dermal papilla is one of the most important structures in hair regeneration. New intervention and reversal strategies for hair loss may arise due to the prevention of oxidative stress. GC/MS analysis was used to determine the compounds contained in NSO. Then, NSO was applied to DPC for cell proliferation and oxidative stress experiments. RNA-seq was performed in cells treated with NSO and minoxidil. The quantitative real-time polymerase chain reaction (qRT-PCR) was applied to verify the gene expression. The effects of NSO on hair length, weight, the number and depth of hair follicles, and the dermal thickness were also studied. GC/MS analysis showed that the main components of NSO were eicosapentaenoic acid, palmitic acid, and linoleic acid. NSO promotes DPC proliferation and reduces H2O2-mediated oxidative damage. NSO can also activate hair growth-related pathways and upregulate antioxidant-related genes analyzed by gene profiling. The topical application of NSO significantly promotes hair growth and increases hair length and weight in mice. NSO extract promotes hair growth and effectively inhibits oxidative stress, which is beneficial for the prevention and treatment of hair loss.


Asunto(s)
Proliferación Celular , Folículo Piloso , Cabello , Estrés Oxidativo , Proliferación Celular/efectos de los fármacos , Animales , Humanos , Folículo Piloso/efectos de los fármacos , Folículo Piloso/metabolismo , Folículo Piloso/crecimiento & desarrollo , Folículo Piloso/citología , Ratones , Estrés Oxidativo/efectos de los fármacos , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Antioxidantes/farmacología , Dermis/metabolismo , Dermis/citología , Dermis/efectos de los fármacos
11.
Chemistry ; 30(49): e202402068, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39136668

RESUMEN

The morphological symmetry-retaining and symmetry-breaking of single crystals of the γ-cyclodextrin metal-organic framework have been achieved via introducing lower symmetric ß-cyclodextrins and α-cyclodextrins, respectively. ß-cyclodextrins led to a morphological evolution with retained symmetry from cubic to rhombic dodecahedra, while α-cyclodextrins resulted in the original cubic crystal missing a vertex angle presenting symmetry-breaking behavior. The crystal structures of rhombic dodecahedra and angle-deficient crystals were confirmed through X-ray crystallography, and the mechanisms underlying the morphological transformation evolution were further analyzed. Our work not only provides a rare case realizing two different paths of morphological evolution in one system, but also encourages future efforts towards the evolution of artificial crystal systems in a natural way.

12.
Chem Commun (Camb) ; 60(59): 7614-7617, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38957034

RESUMEN

A mild and efficient electrochemical method for radical addition, cyclization, and migration reaction was described in this work. A difluoromethyl radical was produced by anodizing CF2HSO2Na. The resulting product was then added to olefin, underwent Smiles cyclization, and migrated to form ß-difluoromethamide compounds after the release of SO2. The process was free from metals and catalysts, gram-grade, and resistant to a variety of electron-rich substrates.

13.
Org Lett ; 26(19): 4071-4076, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38696713

RESUMEN

An electrochemical oxidative difunctionalization of diazo compounds with diselenides and nucleophiles has been developed. This innovative approach yields a diverse array of selenium-containing pyrazole esters and alkoxy esters, overcoming the limitations of traditional synthesis methods. Remarkably, various nucleophiles, including acids, alcohols, and pyrazoles, can be seamlessly incorporated. Notably, this protocol boasts high atom efficiency, excellent functional group tolerance, and good efficiency and operates under transition metal- and oxidant-free conditions, distinguishing it in the field.

14.
Am J Cancer Res ; 14(4): 1561-1576, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726259

RESUMEN

Lung squamous cell carcinoma (LUSC) remains a difficult-to-treat disease with a poor prognosis. While prominin-1 (PROM1/CD-133) is largely investigated in a variety of malignancies, the role of prominin-2 (PROM2), the other member of the prominin family, has not been studied in LUSC. Transcriptomic data derived from matched tumor and adjacent non-tumorous lung tissues of LUSC patients were employed to conduct an in-depth analysis of the genetic and epigenetic regulation of prominin genes within LUSC, utilizing bioinformatic approaches. Furthermore, cellular behavior experiments were executed to discern the biological functions of PROM2. It was observed that PROM2, in contrast to PROM1, exhibited significant upregulation and overexpression at both the mRNA and protein levels in LUSC, and this upregulation was correlated with shortened patient survival. Transcriptomic analysis unveiled DNA methylation as an epigenetic regulatory mechanism associated with PROM2 expression. Notably, two transcription factors, CBFB and NRIP1, were identified as potential regulators of PROM2 expression. Subsequent in vitro investigations demonstrated that knocking down PROM2 led to the inhibition of cancer cell migration and the epithelial-to-mesenchymal transition (EMT). In summary, the pronounced upregulation of PROM2 in LUSC patients was linked to an unfavorable prognosis, possibly attributable to its influence on cancer cell migration and EMT. These findings suggest that PROM2 could serve as a promising diagnostic biomarker and therapeutic target in the management of LUSC. Consequently, further research into the mechanistic aspects and potential therapeutic interventions targeting PROM2 is warranted in the clinical context.

15.
Epilepsy Behav ; 156: 109798, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38788659

RESUMEN

OBJECTIVE: KCNQ2 gene mutation usually manifests as neonatal seizures in the first week of life. Nonsense mutations cause a unique self-limited familial neonatal epilepsy (SLFNE), which is radically different from developmental epileptic encephalopathy (DEE). However, the exact underlying mechanisms remain unclear. METHODS: The proband, along with their mother and grandmother, carried the c.1342C > T (p.Arg448Ter) mutation in the KCNQ2 gene. The clinical phenotypes, electroencephalography (EEG) findings, and neurodevelopmental outcomes were comprehensively surveyed. The mutant variants were transfected into HEK293 cells to investigate functional changes. RESULTS: The proband exhibited behavior arrests, autonomic and non-motor neonatal seizures with changes in heart rate and respiration. EEG exhibited focal sharp waves. Seizures were remitted after three months of age. The neurodevelopmental outcomes at three years of age were unremarkable. A functional study demonstrated that the currents of p.Arg448Ter were non-functional in homomeric p.Arg448Ter compared with that of the KCNQ2 wild type. However, the current density and V1/2 exhibited significant improvement and close to that of the wild-type after transfection with heteromeric KCNQ2 + p.Arg448Ter and KCNQ2 + KCNQ3 + p.Arg448Ter respectively. Channel expression on the cell membrane was not visible after homomeric transfection, but not after heteromeric transfection. Retigabine did not affect homomeric p.Arg448Ter but improved heteromeric p. Arg448Ter + KCNQ2 and heteromeric KCNQ2 + Arg448Ter + KCNQ3. CONCLUSIONS: The newborn carrying the p. Arg448Ter mutation presented frequent behavioral arrests, autonomic, and non-motor neonatal seizures. This unique pattern differs from KCNQ2 seizures, which typically manifest as motor seizures. Although p.Arg448Ter is a non-sense decay, the functional study demonstrated an almost-full compensation mechanism after transfection of heteromeric KCNQ2 and KCNQ3.


Asunto(s)
Electroencefalografía , Canal de Potasio KCNQ2 , Mutación , Humanos , Canal de Potasio KCNQ2/genética , Células HEK293 , Femenino , Masculino , Convulsiones/genética , Convulsiones/fisiopatología , Recién Nacido , Fenilendiaminas/farmacología , Carbamatos/farmacología , Epilepsia Benigna Neonatal/genética , Epilepsia Benigna Neonatal/fisiopatología , Lactante
17.
BMC Musculoskelet Disord ; 25(1): 375, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734632

RESUMEN

BACKGROUND: Synovitis, characterized by inflammation of the synovial membrane, is commonly induced by meniscus tears. However, significant differences in inflammatory responses and the key inflammatory mediators of synovium induced by different types of meniscal tears remain unclear. METHODS: Magnetic resonance imaging (MRI) was employed to identify the type of meniscus tear, and the quantification of synovial inflammation was assessed through H&E staining assay. Transcription and expression levels of IL-1ß and IL-6 were evaluated using bioinformatics, ELISA, RT-qPCR, and IHC of CD68 staining assays. The therapeutic potential of Docosapentaenoic Acid (DPA) was determined through network pharmacology, ELISA, and RT-qPCR assays. The safety of DPA was assessed using colony formation and EdU staining assays. RESULTS: The results indicate that both IL-1ß and IL-6 play pivotal roles in synovitis pathogenesis, with distinct expression levels across various subtypes. Among tested meniscus tears, oblique tear and bucket handle tear induced the most severe inflammation, followed by radial tear and longitudinal tear, while horizontal tear resulted in the least inflammation. Furthermore, in synovial inflammation induced by specific meniscus tears, the anterior medial tissues exhibited significantly higher local inflammation than the anterior lateral and suprapatellar regions, highlighting the clinical relevance and practical guidance of anterior medial tissues' inflammatory levels. Additionally, we identified the essential omega-3 fatty acid DPA as a potential therapeutic agent for synovitis, demonstrating efficacy in blocking the transcription and expression of IL-1ß and IL-6 with minimal side effects. CONCLUSION: These findings provide valuable insights into the nuanced nature of synovial inflammation induced by various meniscal tear classifications and contribute to the development of new adjunctive therapeutic agents in the management of synovitis.


Asunto(s)
Ácidos Grasos Insaturados , Interleucina-1beta , Imagen por Resonancia Magnética , Membrana Sinovial , Sinovitis , Lesiones de Menisco Tibial , Lesiones de Menisco Tibial/tratamiento farmacológico , Lesiones de Menisco Tibial/metabolismo , Sinovitis/tratamiento farmacológico , Sinovitis/metabolismo , Sinovitis/patología , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Humanos , Ácidos Grasos Insaturados/farmacología , Ácidos Grasos Insaturados/metabolismo , Ácidos Grasos Insaturados/uso terapéutico , Masculino , Interleucina-1beta/metabolismo , Animales , Interleucina-6/metabolismo , Femenino , Meniscos Tibiales/efectos de los fármacos , Meniscos Tibiales/metabolismo , Ratones , Modelos Animales de Enfermedad
18.
Org Biomol Chem ; 22(19): 3904-3909, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38656504

RESUMEN

A method for the α-oxidation and sulfonation of benzyl secondary amines was developed utilizing Ir(III) or Eosin Y as the photocatalyst in the presence of O2 as a green oxidant. Using commercial substrates, 37 products from cyclic and acyclic benzylamines were achieved with good functional group compatibility in 48-87% yields. Furthermore, tetrahydroisoquinoline protected by an Ac or a Boc group was oxidized under standard conditions.

19.
Angew Chem Int Ed Engl ; 63(27): e202404295, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38649323

RESUMEN

Homogeneous electrocatalysts can indirect oxidate the high overpotential substrates through single-electron transfer on the electrode surface, enabling efficient operation of organic electrosynthesis catalytic cycles. However, the problems of this chemistry still exist such as high dosage, difficult recovery, and low catalytic efficiency. Single-atom catalysts (SACs) exhibit high atom utilization and excellent catalytic activity, hold great promise in addressing the limitations of homogeneous catalysts. In view of this, we have employed Fe-SA@NC as an advanced redox mediator to try to change this situation. Fe-SA@NC was synthesized using an encapsulation-pyrolysis method, and it demonstrated remarkable performance as a redox mediator in a range of reported organic electrosynthesis reactions, and enabling the construction of various C-C/C-X bonds. Moreover, Fe-SA@NC demonstrated a great potential in exploring new synthetic method for organic electrosynthesis. We employed it to develop a new electro-oxidative ring-opening transformation of cyclopropyl amides. In this new reaction system, Fe-SA@NC showed good tolerance to drug molecules with complex structures, as well as enabling flow electrochemical syntheses and gram-scale transformations. This work highlights the great potential of SACs in organic electrosynthesis, thereby opening a new avenue in synthetic chemistry.

20.
Nat Commun ; 15(1): 3017, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589414

RESUMEN

Diode effects are of great interest for both fundamental physics and modern technologies. Electrical diode effects (nonreciprocal transport) have been observed in Weyl systems. Optical diode effects arising from the Weyl fermions have been theoretically considered but not probed experimentally. Here, we report the observation of a nonlinear optical diode effect (NODE) in the magnetic Weyl semimetal CeAlSi, where the magnetization introduces a pronounced directionality in the nonlinear optical second-harmonic generation (SHG). We demonstrate a six-fold change of the measured SHG intensity between opposite propagation directions over a bandwidth exceeding 250 meV. Supported by density-functional theory, we establish the linearly dispersive bands emerging from Weyl nodes as the origin of this broadband effect. We further demonstrate current-induced magnetization switching and thus electrical control of the NODE. Our results advance ongoing research to identify novel nonlinear optical/transport phenomena in magnetic topological materials and further opens new pathways for the unidirectional manipulation of light.

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