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1.
Angew Chem Int Ed Engl ; 63(23): e202405405, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38578834

RESUMO

The surface frustrated Lewis pairs (SFLPs) open up new opportunities for substituting noble metals in the activation and conversion of stable molecules. However, the applications of SFLPs on a larger scale are impeded by the complex construction process, low surface density, and sensitivity to the reaction environment. Herein, wurtzite-structured crystals such as GaN, ZnO, and AlP are found for developing natural, dense, and stable SFLPs. It is revealed that the SFLPs can naturally exist on the (100) and (110) surfaces of wurtzite-structured crystals. All the surface cations and anions serve as the Lewis acid and Lewis base in SFLPs, respectively, contributing to the surface density of SFLPs as high as 7.26×1014 cm-2. Ab initio molecular dynamics simulations indicate that the SFLPs can keep stable under high temperatures and the reaction atmospheres of CO and H2O. Moreover, outstanding performance for activating the given small molecules is achieved on these natural SFLPs, which originates from the optimal orbital overlap between SFLPs and small molecules. Overall, these findings not only provide a simple method to obtain dense and stable SFLPs but also unfold the nature of SFLPs toward the facile activation of small molecules.

2.
Pediatr Surg Int ; 39(1): 208, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261573

RESUMO

PURPOSE: To investigate the clinical value of enhanced recovery after surgery (ERAS) protocols for children with neuroblastoma (NB). METHODS: This retrospective review was conducted by using the electronic medical records of 48 children with retroperitoneal localized NB who underwent tumor resection (surgery for treatment, not diagnosis) between October 2016 and September 2021. The ERAS protocols for NB excision were implemented in 28 children (ERAS group), while 20 children received traditional care (TRAD group). The same group of pediatric surgeons performed all the tumor resections. Intraoperative fluid infusion, the extent of NB resection, time of early ambulation and time of first flatus, time to total enteral nutrition (TEN) after surgery, abdominal drainages, nasogastric tubes and urinary catheters used and duration, the Face/Legs/Activity/Cry/Consolability (FLACC) quantitative table on a postoperative day 1 (POD1), 3, 5, length of stay after surgery (LOS), hospitalization expense, postoperative complications, parental satisfaction rate and readmission rate of surgical wards within 30 days after operation were analyzed. RESULTS: The median postoperative period of early mobilization, first flatus, TEN, LOS and total cost during hospitalization were 1.0 days, 2.0 days, 5.5 days, 9.0 days and 33,397.3 yuan in the ERAS group and 3.0 days, 3.0 days, 7.0 days, 11.0 days and 38,120.3 Yuan in the TRAD group, respectively (all p < 0.05). Median intraoperative fluid volume was 5.0 mL/kg/h compared to 8.0 mL/kg/h and the magnitude of decrease in FLACC scores from POD1 to POD5 was greater in the ERAS group (all p < 0.05). Abdominal drainages, urinary catheters and nasogastric tubes were removed earlier in the ERAS group (p < 0.05). The satisfaction of parents in the ERAS group was slightly higher, but the difference was not statistically significant (P = 0.762). There were no marked differences between the two groups in aspects of the extent of NB resection, operation-related complications and 30-day readmissions (all P = 1.000). CONCLUSIONS: Application of ERAS protocols in localized retroperitoneal NBs resection in children is feasible and safe. However, applying ERAS protocols in the surgical resection of solid tumors in children still requires much more research, especially randomized prospective research.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Neuroblastoma , Humanos , Criança , Estudos Prospectivos , Flatulência , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia , Neuroblastoma/cirurgia , Estudos Retrospectivos
3.
Phys Chem Chem Phys ; 24(25): 15182-15194, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35707946

RESUMO

Isotope substitution, a fascinating tool of physical chemistry, has been broadly applied in the research field of heterogeneous catalysis. In general, due to the differences in the mass-related atomic vibrational frequencies and zero-point energy of isotopic molecules, the apparent isotope effect (AIE) or observed kinetic isotope effect (observed KIE) from isotope substitution examination could provide unique knowledge regarding the reaction rate and mechanism of a catalytic reaction, such as the rate-determining step, key reaction intermediate, or catalyst design and synthesis. However, the treatment of the AIE is not as straightforward as the isotopic switch experiment, and needs sufficient care and comprehensive identification to deal with the influences from the equilibrium isotope effects (EIEs) of quasi-equilibrium elementary steps, kinetic isotope effect (KIE) of the pseudo rate-determining step, transition states, intrinsic reaction barriers, etc. Fundamentally, the key factors affecting the AIE could be the partition function part and the zero-point energy part of each single elementary step. Theoretically, the classification of the KIE could be based on the quantity of KIE (including normal KIE and inverse KIE) or the molecular transformation (including primary KIE, secondary KIE, tunneling KIE, and solvent KIE) involved. This article presents a recap of the fundamental concepts and relations of KIE, EIE and AIE, and a concise review on the selected applications of isotope effects throughout heterogeneous catalysis. Lastly, the meaningful perspectives regarding the critical factors that impact the AIE and the appropriate treatment of the AIE are discussed meticulously.


Assuntos
Isótopos , Catálise , Físico-Química , Isótopos/química , Cinética , Solventes
4.
Int J Equity Health ; 19(1): 28, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102655

RESUMO

BACKGROUND: Equity is one of the major goals of China's new medical reforms launched in 2009. This study aimed to analyze the disequilibrium in primary health care (PHC) workforce among various economic zones in China and to compare the fairness between urban and rural areas since the implementation of the new medical reforms. METHOD: According to China's 11th Five-Year Plan, China is divided into eight economic regions. The data of this study were obtained from China Statistical Yearbook 2009-2016. The Atkinson index was used to depict the trend of PHC workforce fairness; the Gini coefficient was used to compare the fairness of workforce distribution between urban and rural areas; the health resource agglomeration degree was used to analyze the distributional equity of the workforce in the eight regions; and the Theil Index was used to compare the fairness of urban and rural workforce distribution across eight regions. RESULT: The Atkinson index indicated that the equity of the entire PHC workforce allocation had generally improved during the new medical reforms; the Gini coefficient indicated that the fairness of the entire workforce allocation had improved in cities, but only the nurse allocation became fairer in rural areas. The agglomeration degree and the Theil index indicated that the fairness gaps across the eight regions were still large. These analyses differed from previous studies where China was divided into western, central and eastern regions. In what was previously defined as eastern region, the northeast was under-resourced, while the eastern coastal areas were observing a resource surplus. In western region, we found that the fairness in the northwest was significantly worse than southwest. CONCLUSION: In China, the distribution of healthcare workforce has been improved with continuous effort. The gaps in the distribution of PHC workforce across different economic regions and between urban and rural areas are still large, with different regions facing different problems. The government should consider the population and geographical factors in allocation of PHC workforce, especially nurses.


Assuntos
Equidade em Saúde , Pessoal de Saúde , Mão de Obra em Saúde , Atenção Primária à Saúde , População Rural , Justiça Social , População Urbana , China , Reforma dos Serviços de Saúde , Recursos em Saúde , Humanos
5.
J Phys Chem Lett ; 15(20): 5436-5444, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38743952

RESUMO

The excellent reactivity of frustrated Lewis pairs (FLP) to activate small molecules has gained increasing attention in recent decades. Though the development of surface FLP (SFLP) is prompting the application of FLP in the chemical industry, the design of SFLP with superior activity, high density, and excellent stability for small-molecule activation is still challenging. Herein, we review the progress of designing SFLP by surface engineering, screening natural SFLP, and the dynamic formation of SFLP from theoretical perspectives. We highlight the breakthrough in fine-tuning the activity, density, and stability of the designed SFLP studied by using computational methods. We also discuss future challenges and directions in designing SFLP with outstanding capabilities for small-molecule activation.

6.
J Pediatr Surg ; 56(4): 778-787, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33189302

RESUMO

INTRODUCTION: Neuroblastoma (NB) is the most common solid tumor in children. Studies showed that long-chain noncoding RNA (lncRNA) HCP5 played an important role in tumorigenesis, but its role in NB remained unclear. This study aims to determine the role of HCP5 in NB and its possible molecular mechanism. METHODS: We analyzed the expression levels of miRNA-186-5p and HCP5 in neuroblastoma and neuroblastoma cell lines SHSY-5Y, Kelly, NBL-S and SK-N-AS, and explored their roles. RESULTS: We found that the HCP5 expression was up-regulated in NB tissues and cells. The higher the HCP5 expression in NB cells, the stronger the ability of clone formation. Down regulation of the HCP5 expression inhibited the proliferation of NB cells and the growth of subcutaneous transplanted tumor in nude mice. HCP5 could competitively bind miR-186-5p, while miR-186-5p could target the 3'-UTR of MAP3K2. The expression level of miR-186-5p was down regulated while the expression level of MAP3K2 was up-regulated in NB tissues. The expression level of HCP5 and miR-186-5p, the expression level of miR-186-5p and MAP3K2 were negatively correlated. The decreased proliferation of NB cells induced by down-regulation of HCP5 expression can be counteracted by miR-186-5p inhibitor or MAP3K2, and vice versa. CONCLUSION: This study showed that lncRNA HCP5, as ceRNA, regulated MAP3K2 to promote NB progression through competitive binding of miR-186-5p. We revealed a new signaling pathway that mediates NB, which provided a new target for the diagnosis and treatment of NB.


Assuntos
MicroRNAs , Neuroblastoma , RNA Longo não Codificante , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MAP Quinase Quinase Quinase 2 , Camundongos , Camundongos Nus , MicroRNAs/genética , Neuroblastoma/genética , RNA Longo não Codificante/genética
7.
Ultrason Sonochem ; 64: 105039, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32097866

RESUMO

A sonochemical reactor was developed to study the ultrasound-assisted cyanide extraction of gold from gold ore at low temperature. The effects of ultrasound on gold leaching in low temperature and conventional conditions were investigated. At the low temperature of 10 °C, ultrasound-assisted extraction increased extraction rate of gold by 0.6%-0.8% and reduced the gold content of cyanide tailings to 0.28 g/t in the leaching of gold concentrate and cyanide tailings, respectively. At the conventional temperature of 25 °C, ultrasound-assisted extraction obtained a 0.1% higher extraction rate of gold compared with conventional extraction, with the unit consumption of NaCN reduction of 15%. The analysis of kinetic model also demonstrated that sonication indeed improved the reaction of gold leaching greatly. The mineralogy and morphology of ore were further analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and particle size analyzer to explore the strengthening mechanism of gold leaching. The results showed that the ore particles were smashed, the ore particle surface was peeled, the passive film was destroyed and the reaction resistance decreased under ultrasonic processing. Therefore, the extraction rate of gold was improved and the extraction time was shortened significantly in ultrasound-assisted cyanide extraction.

8.
Medicine (Baltimore) ; 96(10): e6209, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272213

RESUMO

Both the Swenson and the Soave procedures have been adapted as transanal approaches. Our purpose is to compare the outcomes and complications between transanal Swenson and Soave procedures.This clinical analysis involved a retrospective series of 148 pediatric patients with HD from Dec, 2001, to Dec, 2015. Perioperative/operative characteristics, postoperative complications, and outcomes between the 2 groups were analyzed. Students' t-test and chi-squared analysis were performed.In total 148 patients (Soave 69, Swenson 79) were included in our study. Mean follow-up was 3.5 years. There are no significant differences in overall hospital stay and bowel function. We noted significant differences regarding mean operating time, blood loss, and overall complications. We noted significant differences in mean operating time, blood loss, and overall complications in favor of the Swenson group when compared to the Soave group (P < 0.05).According to our results, although transanal pullthrough Swenson cannot reduce overall hospital stay and improve bowel function compared with the Soave procedure, it results in less blood loss, shorter operation time, and a lower complication rate.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Doença de Hirschsprung/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/estatística & dados numéricos , Humanos , Lactente , Estudos Retrospectivos
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