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1.
Chem Commun (Camb) ; 60(44): 5715-5718, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38739371

RESUMO

Here, Selective C3-formylation of indole was achieved under mild conditions using a metal-organic framework (MOF) catalyst. The confined reaction space within the MOF pores effectively suppressed undesired side reactions and promoted the formation of the targeted product by controlling the reaction pathway. Density functional theory (DFT) calculations corroborated the experimental observations.

2.
J Asian Nat Prod Res ; : 1-6, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426506

RESUMO

Two new cassane diterpenoids, sucupiranin MN (1) and sucupiranin ML (2), together with two known compounds sucutinirane C (3) and deacetylsucutinirane C (4) were isolated from the seed kernels of Caesalpinia sinensis. Their structures were elucidated by means of analysis of comprehensive spectroscopic data, especially HRESIMS and 1D/2D NMR spectroscopy. Compounds 1-4 are typical furan-type cassane derivatives with an aromatized C ring. Biological evaluation revealed that compounds 1-4 at the concentration of 10 µM could inhibit the overproduction of NO in LPS-stimulated RAW 264.7 macrophages.

3.
Sci Rep ; 14(1): 1559, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238563

RESUMO

Microbial cement, known for its superior fluidity, stable crystal formation, and strong bond with concrete, is an effective solution in fixing defects such as voids that appear due to insufficient grouting in the joints of precast concrete components. To evaluate the mechanical properties of rebar anchored with microbial cement grout, three pull-out tests were designed, taking into account parameters such as calcium source concentration, the filler in borehole voids, and the shape of the rebar. The results indicate that specimens with a higher concentration of calcium source require fewer grouting cycles, but the pull-out bearing capacity of the anchored rebar is lower. However, the introduction of quartz sand as a filler in the borehole voids results in a significant increase in the pull-out bearing capacity of the rebar compared to specimens without filler. Among these, the specimens with a medium particle size of 0.5 ~ 1 mm (1/4δ ~ 1/2δ, the gap of δ = 2 mm between the steel bars and hole wall) have the highest pull-out bearing capacity. In comparing rebar shapes, ribbed rebar slightly outperforms smooth round rebar in terms of pull-out bearing capacity. Based on the experimental results analysis, the anchoring mechanism of microbial cement grouting on reinforcement has been elucidated.

4.
ChemSusChem ; 15(20): e202201301, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35909080

RESUMO

A highly efficient and elegant diversity-oriented reaction paradigm employing atropaldehyde acetals as new dual C2/C3 synthons was developed under metal-free conditions using glycine esters as the counterpart reagents, which allowed rapid synthesis of two important nitrogen-containing heterocycles, pyrrolo[1,2-a]quinolines and 3,5-diarylpyridines. The divergent products are subtly controlled by the manipulation of the substitutional groups of glycine esters. When a N-arylglycine ester was used, pyrrolo[1,2-a]quinolines can be formed through cascade oxidative C-C cleavage/multiple cyclization. Instead, N-benzylglycine ester as the counter-reagent led to the synthesis of 3,5-diarylpyridines via two key C-N cleavages. Mild conditions, broad substrate scope, scalability and environmentally acceptable organic solvents rendered this method practical and attractive.


Assuntos
Acetais , Quinolinas , Nitrogênio , Catálise , Ésteres , Glicina , Solventes
5.
Chemistry ; 28(29): e202200502, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35388931

RESUMO

Functional phase-change materials (PCMs) are conspicuously absent in various organic or inorganic solids with diversified applications in which the attributes of these molecular materials have been highly realized. Leakage problem during the phase transition process is the main obstacle on the way of widely use of solid-liquid PCMs who has been recognized to be promisingly practical candidates for energy storage owing to the high energy storage density and small volume change in the phase transition process. Herein, a novel homogeneous-to-heterogeneous-strategy, in which all the starting materials involved display a homogeneous state and the encapsulation framework formed in situ in the encapsulation process, enabled by an aerogel reaction of silica was realized under the catalysis of an organic base. Besides the comprehensive study upon energy storage performance, light-to-thermal conversion and recyclability performance study of the obtained materials reveal the clear superiority over pristine paraffin wax (PW) thanks to the versatility and robustness of this fabrication method. More importantly, the homogeneous-to-heterogeneous-strategy endows a unique adsorption ability with respect to organic pollutant due to the PCMs inside and therefore bearing a great potential to be used in environment protection fields.

6.
Zhongguo Gu Shang ; 30(7): 622-626, 2017 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-29424151

RESUMO

OBJECTIVE: To explore the clinical effect of closed reduction and minimally invasive treatment of humeral shaft fractures in children. METHODS: From July 2011 to April 2015, 39 cases of pediatric humeral shaft fractures were treated by closed reduction and external fixation, including 27 males and 12 females with a mean age of 8.6 years old ranging from 3 to 14 years old. Time from injury to the treatment was 2 h to 7 days with an average of 2.7 days. There were 6 cases of upper fracture, 21 cases of middle fracture and 12 cases of lower fracture. All children were closed injury, appeared pain, swelling, local deformity and limited mobility and other symptoms after injury. X-ray examination showed humeral shaft fracture. Neer score of shoulder joint function and HSS score of elbow joint function were used to record and analyze the pain, function and activity of shoulder and elbow joint before and after treatment. RESULTS: All the 39 cases were followed up for 6 to 12 months with a mean of 8.6 months. Two cases appeared postoperative superficial infection of the needle, and healed after dress; other cases gained good pinhole healing. There were significant differences in the pain, function and activity of the shoulder of Neer score before and after the treatment (P<0.05). There were significant differences in the pain and function of the elbow of HSS before and after treatment (P<0.05). According to the evaluation of Neer score of shoulder function, the total score was 88.82±2.50, 29 cases were excellent, 9 cases were good, and 1 case was fair. According to the evaluation of HSS score of elbow joint function evaluation, the total score was 91.51±5.09, 30 cases were excellent, 7 cases were good, 2 cases were general. CONCLUSIONS: Manual closed reduction combined with external fixation for the treatment of humeral shaft fractures in children has advantages of less trauma, definite reduction effect, reliable fixation and benefit for early functional exercise of the shoulder and elbow joint. This therapy can be used as one of clinical methods for the treatment of humeral shaft fractures in children.


Assuntos
Fixação de Fratura/métodos , Fraturas do Úmero/cirurgia , Adolescente , Placas Ósseas , Criança , Pré-Escolar , Articulação do Cotovelo/fisiopatologia , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
Zhongguo Gu Shang ; 30(7): 664-668, 2017 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-29424160

RESUMO

OBJECTIVE: To observe the effect of different manipulative reduction for children's distal radioulnar fracture and dorsal dislocation. METHODS: From June 2013 to June 2014, 80 children with distal radioulnar fracture and dorsal dislocation were treated by bone setting manipulative reduction including 51 males and 29 females with an average age of 6.5 years old ranging from 3 to 14 years old. Time from injury to treatment was 1 h to 6 d, 31 cases were on the right, 49 cases were on the left. Among them, 45 cases were type I of overlapping displacement, 35 cases were type II. The displacement of the fracture was observed by clinical manifestations and X-ray examination. Under fluoroscopy, different techniques were used for reduction and fixation. After 3 weeks of over wrist fixation, the splints were overturned and fixed again for 1 to 2 weeks, then were removed. The wrist joint function was evaluated based on Dienst criteria. RESULTS: Eighty cases of fracture were successfully operated one time, all reached anatomic reduction or near anatomic reduction. Eighty children were followed up for 3 months to 1 year. All the fractures healed, and the healing time was 4 to 5 weeks with an average of 4.6 weeks. All patients removed the splint 3 months later, the results were excellent in 72 cases, good in 7 cases and fair in 1 case, the excellent and good rate was 98.75%. CONCLUSIONS: Bone setting manipulation for children's distal radioulnar fracture and dorsal dislocation can get good reduction. At 1 month after the removal of the splint, wrist function and finger strength gradually recovered and returned to normal after 3 months.


Assuntos
Redução Fechada/métodos , Luxações Articulares/terapia , Fraturas do Rádio/terapia , Fraturas da Ulna/terapia , Traumatismos do Punho/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Contenções , Tempo para o Tratamento
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