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1.
Phys Rev Lett ; 133(3): 036003, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39094159

RESUMO

This work reports on the emergence of quantum Griffiths singularity (QGS) associated with the magnetic field induced superconductor-metal transition (SMT) in unconventional Nd_{0.8}Sr_{0.2}NiO_{2} infinite layer superconducting thin films. The system manifests isotropic SMT features under both in-plane and perpendicular magnetic fields. Importantly, after scaling analysis of the isothermal magnetoresistance curves, the obtained effective dynamic critical exponents demonstrate divergent behavior when approaching the zero-temperature critical point B_{c}^{*}, identifying the QGS characteristics. Moreover, the quantum fluctuation associated with the QGS can quantitatively explain the upturn of the upper critical field around zero temperature for both the in-plane and perpendicular magnetic fields in the phase boundary of SMT. These properties indicate that the QGS in the Nd_{0.8}Sr_{0.2}NiO_{2} superconducting thin film is isotropic. Moreover, a higher magnetic field gives rise to a metallic state with the resistance-temperature relation R(T) exhibiting lnT dependence among the 2-10 K range and T^{2} dependence of resistance below 1.5 K, which is significant evidence of Kondo scattering. The interplay between isotropic QGS and Kondo scattering in the unconventional Nd_{0.8}Sr_{0.2}NiO_{2} superconductor can illustrate the important role of rare region in QGS and help to uncover the exotic superconductivity mechanism in this system.

2.
J Org Chem ; 89(16): 11671-11681, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39096319

RESUMO

2-Alkyl chromanone scaffold has become prominent in pharmaceuticals and natural compounds. Consequently, devising robust strategies for synthesizing 2-alkyl chromanones remains crucial. Here, multicomponent reactions were employed to synthesize 2-alkyl chromanones containing an oxazole moiety using 3-formylchromones, amines, and N-propargylamides as reactants. This method utilizes readily available feedstocks with a catalytic amount of Zn(OTf)2 and exhibits an impressive substrate scope compared to existing methods. Importantly, the synthesized compounds demonstrated highly selective anticancer activity against the DU145 cell line.


Assuntos
Antineoplásicos , Cromonas , Ácidos de Lewis , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Humanos , Cromonas/química , Cromonas/farmacologia , Cromonas/síntese química , Linhagem Celular Tumoral , Ácidos de Lewis/química , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Catálise , Relação Estrutura-Atividade
3.
Environ Res ; 248: 118305, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38307183

RESUMO

Chlorinated polyfluorinated ether sulfonate (F-53B), a substitute of perfluorooctane sulfonic acid (PFOS), has attracted significant attention for its link to hepatotoxicity and enterotoxicity. Nevertheless, the underlying mechanisms of F-53B-induced enterohepatic toxicity remain incompletely understood. This study aimed to explore the role of F-53B exposure on enterohepatic injury based on the gut microbiota, pathological and molecular analysis in mice. Here, we exposed C57BL/6 mice to F-53B (0, 4, 40, and 400 µg/L) for 28 days. Our findings revealed a significant accumulation of F-53B in the liver, followed by small intestines, and feces. In addition, F-53B induced pathological collagen fiber deposition and lipoid degeneration, up-regulated the expression of fatty acid ß-oxidation-related genes (PPARα and PPARγ, etc), while simultaneously down-regulating pro-inflammatory genes (Nlrp3, IL-1ß, and Mcp1) in the liver. Meanwhile, F-53B induced ileal mucosal barrier damage, and an up-regulation of pro-inflammatory genes and mucosal barrier-related genes (Muc1, Muc2, Claudin1, Occludin, Mct1, and ZO-1) in the ileum. Importantly, F-53B distinctly altered gut microbiota compositions by increasing the abundance of Akkermansia and decreasing the abundance of Prevotellaceae_NK3B31_group in the feces. F-53B-altered microbiota compositions were significantly associated with genes related to fatty acid ß-oxidation, inflammation, and mucosal barrier. In summary, our results demonstrate that F-53B is capable of inducing hepatic injury, ileitis, and gut microbiota dysbiosis in mice, and the gut microbiota dysbiosis may play an important role in the F-53B-induced enterohepatic toxicity.


Assuntos
Microbioma Gastrointestinal , Ileíte , Camundongos , Animais , Disbiose , Peixe-Zebra/metabolismo , Camundongos Endogâmicos C57BL , Fígado , Ácidos Graxos/metabolismo
4.
Pathol Res Pract ; 256: 155230, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461693

RESUMO

Papillary thyroid carcinoma (PTC) is generally recognized as a slow-growing tumor. However, a small subset of patients may still experience relapse or metastasis shortly after therapy, leading to a poor prognosis and raising concerns about excessive medical treatment. One major challenge lies in the inadequacy of effective biomarkers for accurate risk stratification. Long non-coding RNAs (lncRNAs), which are closely related to malignant characteristics and poor prognosis, play a significant role in the genesis and development of PTC through various pathways. The objective of this review is to provide a comprehensive summary of the biological functions of lncRNAs in PTC, identify prognosis-relevant lncRNAs, and explore their potential mechanisms in drug resistance to BRAF kinase inhibitors, tumor dedifferentiation, and lymph node metastasis. By doing so, this review aims to offer valuable references for both basic research and the prediction of PTC prognosis.


Assuntos
Carcinoma Papilar , RNA Longo não Codificante , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/genética , Prognóstico , Neoplasias da Glândula Tireoide/patologia , RNA Longo não Codificante/genética , Carcinoma Papilar/patologia , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas B-raf/metabolismo
5.
J Hazard Mater ; 474: 134808, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38861903

RESUMO

The release of carbon disulfide can have adverse effects on our environment and human health. The stability of carbon disulfide and the slow kinetics of hydrolysis can make it challenging to achieve efficient and practical cleavage of the CS bonds. Herein, a calix[4]arene-based porous organic polymer (CPOP-1) is innovatively synthesized through an optimized polycondensation reaction using C-Methylcalix[4]resorcinarene and hexafluoro-hexaazatriphenylene as monomers. Subsequently, palladium-induced calix[4]arene-based porous organic polymer was also synthesized via strong Pd-N coordination bonds to construct the metal-induced porous catalyst (CPOP-2). The polymeric catalyst active center [Pd2+(N^N)(NO3-)2] demonstrated outstanding catalytic hydrolysis performance (11.14 µmol g-1 h-1) in 10.5 h which is significantly enhanced by ca.13.2 times as compared to reported mononuclear Bpy-Pd(NO3)2, and 7.07 times than model trinuclear complex catalyst HATN-Pd-1, respectively. The control experiments revealed that POP catalysts showcased robust stability, prolonged effectiveness, and feasible recyclability during the hydrolytic cleavage of carbon disulfide at room temperature in aqueous solutions. Furthermore, the coordination environment of [Pd2+(N^N)] was validated through XPS, EXAFS, and isotope labeling measurements, and the hydrolysis cleavage products were confirmed e. g. CO2, sulfide, and protons. More importantly, a reaction mechanism was formulated coupled with theoretical calculations, and simulations. The proposed mechanism involves sequential OH- nucleophilic attacks on the carbon atoms of insert-coordinated CS2 and COS, leading to the cleavage of double CS bonds and the formation of CO bonds. The concurrent dissociation of the C-S bond and liberation of CO2 result in an intermediate structure characterized by [(N^N)Pd2+](SH-)2. This intermediate motif serves as the source of the thermodynamic driving force for the reaction.

6.
J Integr Med ; 22(1): 39-45, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38311541

RESUMO

BACKGROUND: As one of the most common musculoskeletal ailments, chronic nonspecific low-back pain (CNLBP) causes persistent disability and substantial medical expenses. Epidemiological evidence shows that the incidence rate of CNLBP in young and middle-aged people who are demanded rapidly recovery and social contribution is rising. Recent guidelines indicate a reduced role for medicines in the management of CNLBP. OBJECTIVE: The present study investigates the short-term effects of cupping and scraping therapy using a medicated balm, compared to nonsteroidal anti-inflammatory drug (NSAID) with a capsaicin plaster, in the treatment of CNLBP. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: We designed a prospective multicenter randomized clinical trial enrolling patients from January 1, 2022 to December 31, 2022. A total of 156 patients with CNLBP were randomized into two parallel groups. Diclofenac sodium-sustained release tablets were administered orally to participants in the control group for one week while a capsaicin plaster was applied externally. Patients in the test group were treated with cupping and scraping using a medical device and medicated balm. MAIN OUTCOME MEASURES: Primary outcome was pain recorded using the visual analogue scale (VAS). Two secondary outcomes were recorded using the Japanese Orthopedic Association low-back pain scale (JOA) and the traditional Chinese medicine (TCM) syndrome integral scale (TCMS) as assessment tools. RESULTS: Between baseline and postintervention, all changes in outcome metric scales were statistically significant (P < 0.001). Compared to the control group, patients in the test group had a significantly greater treatment effect in all outcome variables, as indicated by lower VAS and TCMS scores and higher JOA scores, after the one-week intervention period (P < 0.001). Further, according to the findings of multivariate linear regression analysis, the participants' pain (VAS score) was related to their marital status, age, smoking habits and body mass index. No adverse reactions were reported for any participants in this trial. CONCLUSION: The effectiveness of TCM combined with the new physiotherapy tool is superior to that of NSAID combined with topical plasters, regarding to pain intensity, TCM symptoms and quality of life. The TCM plus physiotherapy also showed more stable and long-lasting therapeutic effects. TRIAL REGISTRATION: This study was registered at Chinese Clinical Trial Registry (ChiCTR2200055655). Please cite this article as: He JY, Tu XY, Yin ZF, Mu H, Luo MJ, Chen XY, Cai WB, Zhao X, Peng C, Fang FF, Lü C, Li B. Short-term effects of cupping and scraping therapy for chronic nonspecific low-back pain: A prospective, multicenter randomized trial. J Integr Med. 2024; 22(1): 39-45.


Assuntos
Dor Crônica , Dor Lombar , Humanos , Anti-Inflamatórios não Esteroides/uso terapêutico , Capsaicina/uso terapêutico , Dor Crônica/terapia , Dor Lombar/terapia , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento
7.
World Neurosurg ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38986944

RESUMO

OBJECTIVE: We designed this study to introduce the surgical strategy cerebrospinal fluid (CSF) decompression in treatment of Chiari malformation type I and compared CSF decompression with other surgical strategies to provide a solid basis for patient counseling. METHODS: The study enrolled 528 consecutive patients with CMI who underwent surgical interventions from 2012 to 2022. The surgical strategy for these patients was bony and dural decompression, anatomical reduction of herniated tonsils, or CSF decompression. Short-term results were determined after 3 months; long-term outcomes were evaluated at last follow-up (at least 18 months). RESULTS: CSF decompression was independently associated with better long- or short-term primary outcomes than anatomical reduction of herniated tonsils or bony and dural decompression (P < 0.001). Compared with short-term, the long-term outcomes were better in patients who underwent CSF decompression (P = 0.035), but were worse in patients with bony and dural decompression (P = 0.03). Specific surgical techniques cannot affect the long- and short-term outcomes of patients with Chiari malformation type I. CSF decompression provided better long-term syringomyelia improvement than short-term (181/218, 83% vs. 169/218, 77.5%; P < 0.001). CONCLUSIONS: CSF decompression, but not a specific surgical technique or operative method, was associated with favorable neurological outcomes in ADULT patients with Chiari malformation type I. The surgical technique and operative method should be selected according to the characteristics of each patient and the intraoperative condition to normalize CSF circulation at the craniovertebral junction area. The intraoperative target, smooth CSF flow out from the fourth ventricle and in to the bilateral Luschka foramina, could be observed.

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