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1.
Sci Total Environ ; 922: 171337, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428596

RESUMO

Throughout history, there were many fine mural paintings concealed within ancient buildings, hidden beneath layers of plaster, wall or other structure. In recent decades, research and practical efforts had primarily focused on nondestructive diagnosis of these hidden murals and the removal of their surface coverings. However, limited attention had been given to the consequences of overlay removal on mural preservation. This study aims to address this gap by examining the revealed mural paintings in the Prince Shi's Palace as a case study, employing an analysis of mural ontology, investigation into the preservation environment, and simulation experiments to comprehensively analyze the factors contributing to the rapid deterioration of these revealed murals. The findings indicated that certain carbonated lime particles adhered to the mural surface, and in a humid environment, these particles absorbed sulfur dioxide from the atmosphere and converted into calcium sulfate. The strong hygroscopic property of calcium sulfate enhanced the humidity on the surface of murals, thereby increasing their susceptibility to sulfur dioxide absorption. Over time, the murals suffered more sulphate and moisture damage. Additionally, historically inaccurate interventions such as non-breathable shading curtains installation and organic coatings reinforcement exacerbated this deterioration process. Therefore, safeguarding the integrity of these exposed concealed murals necessitated prioritizing the preservation of environmental humidity and acid gas levels.

2.
J Pharm Pharmacol ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422325

RESUMO

OBJECTIVES: Schisandrin B (Sch B) has been shown to possess anti-inflammatory and antioxidant properties, however, its antirheumatoid arthritis properties and potential mechanism remain unexplored. This study evaluated the potential of Sch B in adjuvant-induced arthritic (AIA) rats. METHODS: AIA was induced by injecting 0.1 ml of CFA into the paw of rats and the animals were administered with Sch B (50 mg/kg) for 28 days. The effects of Sch B were evaluated using arthritis severity, serum levels of oxido-inflammatory, and metabolic index parameters. KEY FINDINGS: Sch B eased arthritic symptoms by significantly reducing paw swelling and arthritic score and increased body weight gain. Moreover, Sch B alleviated the levels of oxido-inflammatory markers including interleukin-1 beta, interleukin-6, tumor necrosis factor alpha, nuclear factor kappa B, transforming growth factor ß1, inducible nitric oxide synthase and malonaldehyde, as well as increased the levels of superoxide dismutase, glutathione, and Nrf2. Sch B also remarkably restored the altered levels of triglyceride, aspartate aminotransferase, lactic acid, pyruvate, phosphoenolpyruvate carboxylase, glucose, hypoxia inducible factor-1 alpha, and vascular endothelial growth factor. In addition, Sch B markedly alleviated p65 expression in the treated AIA rats. CONCLUSION: This study suggests that Sch B alleviated AIA by reducing oxidative stress, inflammation, and angiogenesis.

3.
Medicine (Baltimore) ; 102(20): e33833, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335703

RESUMO

The objective of this study was to investigate the diagnostic model of osteoarthritis by bone turnover markers in Chinese middle-aged subjects. The study was designed as a cross-sectional investigation with 305 participants aged 45 to 64. Radiographs of tibiofemoral knee joints were used for diagnose osteoarthritis. Radiographic grading, evaluated using the Kellgren and Lawrence grading scale (K-L), was scored by 2 experienced observers who were blinded to the source of subjects. An optimal model was developed by logistic regression. And the prognostic performance of the selected model was assessed by the area under the receiver operating characteristic curve. The prevalence of osteoarthritis was 52.29% (n = 137/262) in middle age. ß-CTx levels tended to increase according to the K-L grades, whereas PTH levels significantly decrease. levels of 25(OH)D, ß-CTx, and PTH were each significantly associated with osteoarthritis risk (P < .05). Based on the estimated parameters of the optimal model, a nomogram was constructed for predicting osteoarthritis. These data suggest that the combination of PTH and ß-CTx could significantly improve the prognosis of osteoarthritis in middle age, and that the nomogram can assist primary physicians in the identification of high-risk men.


Assuntos
Osteoartrite do Joelho , Osteoartrite , Masculino , Humanos , Pessoa de Meia-Idade , Estudos Transversais , Nomogramas , Osteoartrite/diagnóstico por imagem , Colágeno , Biomarcadores , Remodelação Óssea , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/epidemiologia
4.
Front Chem ; 10: 1048467, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518981

RESUMO

Pyrrolizidine alkaloids (PAs) are a series of ubiquitous natural toxins in flowering plants, which are associated with serious hepatic disease in humans. However, the simultaneously fast and sensitive monitoring of different PAs are still challenge because of the diversity of PAs and huge amount of interference in complex samples, such as scented tea samples. In this study, molecularly imprinted solid phase microextraction (MIP-SPME) fibers were fabricated by using multi-template imprinting technique for selective recognition and efficient enrichment of different PAs from scented teas. MIP-SPME could be used for selective adsorption of ten types of PAs through specific recognition cavity and strong ionic interaction, including senecionine, lycopsamine, retrorsine, heliotrine, lasiocarpine, monocrotaline, echimidine, erucifoline, europine and seneciphylline. The extraction parameters were also optimized including extraction time, elution solvent and elution time. Then, ultra performance liquid chromatography- quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS) coupled with MIP-SPME method was developed for fast, simple, sensitive and accurate determination of ten PAs in scented teas. The established method was validated and presented satisfactory accuracy and high precision. It was also successfully applied for simultaneous determination of ten PAs in different scented tea samples. PAs were found in most of these scented tea samples, which suggest the cautious use of scented tea for consumers.

6.
ACS Appl Mater Interfaces ; 10(41): 35430-35440, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30247021

RESUMO

High-performance photovoltaic polymers bearing cross-linkable function together with a photorobust conjugated backbone are highly desirable for organic solar cells to achieve both high device efficiency and long-term stability. In this study, a family of such polymers is reported based on poly[(2,5-bis(2-hexyldecyloxy)phenylene)- alt-(5,6-difluoro-4,7-di(thiophen-2-yl)benzo[ c]-[1,2,5]thiadiazole)] (PPDT2FBT), a high-performance photovoltaic donor-acceptor polymer, with different contents of terminal vinyl-appended side chains for cross-linking. The polymers were named PPDT2FBT-V x and prepared by varying the feeding ratio ( x mol %, x = 0, 5, 10, and 15) of the vinyl-appended monomer in polymerization. It was found that the vinyl integration did not sacrifice the original high photovoltaic performance of the polymers, as evidenced by comparable average power conversion efficiencies (PCEs) (6.95, 7.02, and 7.63%) observed for optimized devices based on PPDT2FBT-V0, PPDT2FBT-V5, and PPDT2FBT-V10, respectively, in blending with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM). Unlike thermal cross-linking that greatly reduced device efficiency, UV cross-linking has proven to be an effective way to achieve both high device efficiency and thermostability for PPDT2FBT-V10 solar cells. UV-cross-linked PPDT2FBT-V10 solar cells displayed an initial average PCE of 5.28% and almost no decrease upon heat treatment at 120 °C for 40 h. Morphology studies revealed that UV-cross-linking did not only alter initial nanophase separation but also suppressed morphology evolution by aggregation in bulk heterojunction blend films. Photo-cross-linking requires material photostability. It is therefore worthwhile to note that these polymers and their blends with PC71BM were found to be extremely photostable, even upon continuous exposure to concentrated sunlight (up to 200 suns), and UV-cross-linking does not hamper this photostability. Further studies found that the devices fabricated with the UV-cross-linked PPDT2FBT-V10/PC71BM active layer can endure continuous light exposure to a solar simulator without deteriorating their performance.

7.
Zhongguo Gu Shang ; 31(3): 213-216, 2018 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-29600669

RESUMO

OBJECTIVE: To explore clinical effect of modified Chevron osteotomy combined with lateral tissue loosening for the treatment of mild-moderate hallux valgus through internal signal approach. METHODS: From July 2015 to June 2016, 26 patients with mild-moderate hallux valgus treated with modified Chevron osteotomy combined with lateral tissue loosening through internal signal approach, including 2 males and 24 females aged from 45 to 65 years old with an average of(54.6±4.8) years old;the courses of diseases ranged from 1 to 5 months with an average of (7.5±3.3) months. Hallux valgus angle(HVA), inter metatarsal angle(IMA) were measured at 12 months after operation, and AOFAS score was applied to evaluate clinical effect before and after operation. RESULTS: All incisions were healed at stage I. No incision occurred infection, metatarsal necrosis and recurrence of hallux valgus deformity. Two patients occurred skin numbness caused by musculocutaneous nerve injury. Twenty-six patients were followed up from 6 to 12 months with an average of(9.12±2.06) months. HVA, IMA were(30.01±3.71)°, (14.00±1.50)° before operation and(9.41±4.16)°, (7.00±0.60)° after operation, which had significant difference. There was statistical significance in AOFAS score before operation 54.77±9.59 and after operation 92.73±5.47, and 19 cases obtained excellent results and 7 moderate. CONCLUSIONS: Modified Chevron osteotomy combined with full thread headless pressure screw fixation and lateral tissue loosening for the treatment of mild-moderate hallux valgus has advantages of excellent exposure, simple operation, stable fixation, rapid recovery. Akin osteotomy with internal capsulorrhaphy were used with lateral loosening and could recover soft tissue balance between lateral and internal, and could receive satisfied clinical effects.


Assuntos
Hallux Valgus/cirurgia , Osteotomia/métodos , Idoso , Feminino , Humanos , Masculino , Ossos do Metatarso/patologia , Pessoa de Meia-Idade , Radiografia , Recidiva , Resultado do Tratamento
8.
RSC Adv ; 8(42): 23546-23554, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35540294

RESUMO

The formation of high quality homogeneous active component films is essential to the fabrication of many organic optoelectronic devices, especially those having a large area module. However, most small molecule (SM) semiconductors are unable to achieve such a goal via solution processing because their large and rigid π-conjugated structures generally drive them to aggregate or crystallize into inhomogeneous domains in the process. In this work, a SM semiconductor (SM-DPP6T) based on a diketopyrrolopyrrole (DPP) center with three thiophene units on both sides encounters the same problem. However, when its molecules are interconnected with soft alkyl linkers and change into a poly(rod-coil) polymer, PRC-DPP6T, the problem is solved. Compared with SM-DPP6T, PRC-DPP6T can form a high quality homogeneous film with much better uniformity and coverage on silicon wafers by spin-coating. Moreover, the so-prepared PRC-DPP6T field-effect transistors displayed a much narrower performance distribution and comparable mobility when compared with those based on SM-DPP6T (0.17 vs. 0.15 cm2 V-1 s-1). These results demonstrate that the interconnection of SM semiconductor molecules with soft non-conjugated linkers is a promising way to improve film formation quality while keeping mobility intact.

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