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1.
Front Oncol ; 12: 950418, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387243

RESUMO

Background: Peritoneal sarcomatosis (PS) could occur in patients with retroperitoneal sarcomas (RPS). This study aimed to expand the understanding of PS on its characteristics and prognostic role, and develop a nomogram to predict its occurrence preoperatively. Methods: Data of 211 consecutive patients with RPS who underwent surgical treatment between 2011 and 2019 was retrospectively reviewed. First, the clinicopathological characteristics of PS were summarized and analyzed. Second, the disease-specific survival (DSS) and recurrence-free survival (RFS) of patients were analyzed to evaluate the prognostic role of PS. Third, preoperative imaging, nearly the only way to detect PS preoperatively, was combined with other screened risk factors to develop a nomogram. The performance of the nomogram was assessed. Results: Among the 211 patients, 49 (23.2%) patients had PS with an incidence of 13.0% in the primary patients and 35.4% in the recurrent patients. The highest incidence of PS occurred in dedifferentiated liposarcoma (25.3%) and undifferentiated pleomorphic sarcoma (25.0%). The diagnostic sensitivity of the preoperative imaging was 71.4% and its specificity was 92.6%. The maximum standardized uptake value (SUVmax) was elevated in patients with PS (P<0.001). IHC staining for liposarcoma revealed that the expression of VEGFR-2 was significantly higher in the PS group than that in the non-PS group (P = 0.008). Survival analysis (n =196) showed significantly worse DSS in the PS group than in non-PS group (median: 16.0 months vs. not reached, P < 0.001). In addition, PS was proven as one of the most significant prognostic predictors of both DSS and RFS by random survival forest algorithm. A nomogram to predict PS status was developed based on preoperative imaging combined with four risk factors including the presentation status (primary vs. recurrent), ascites, SUVmax, and tumor size. The nomogram significantly improved the diagnostic sensitivity compared to preoperative imaging alone (44/49, 89.8% vs. 35/49, 71.4%). The C-statistics of the nomogram was 0.932, and similar C-statistics (0.886) was achieved at internal cross-validation. Conclusion: PS is a significant prognostic indicator for RPS, and it occurs more often in recurrent RPS and in RPS with higher malignant tendency. The proposed nomogram is effective to predict PS preoperatively.

2.
J Surg Oncol ; 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36444482

RESUMO

BACKGROUND AND OBJECTIVES: Resection of retroperitoneal sarcoma (RPS) en bloc with pancreas is challenging and controversial. This single-center retrospective study aimed to analyze the impact of pancreatic resection (PR) and its different types on short- and long-term outcomes in patients with RPS. METHODS: Data from 242 consecutive patients with RPS who underwent surgical treatment at the Peking University Cancer Hospital Sarcoma Center between January 2010 and February 2021 were analyzed. Out of these, 90 patients underwent PR, including pancreaticoduodenectomy (PD) in 31 and distal pancreatectomy (DP) in 59. RESULTS: Patients in the PR group had a higher major morbidity (37.8% vs. 14.5%) and mortality (8.9% vs. 1.3%) than those in the non-PR group, with a similar 5-year overall survival (OS) rate (46.9% vs. 53.6%). Patients in the PD and DP groups had a slight difference in major morbidity (48.4% vs. 32.2%), mortality (6.4% vs. 10.2%), and 5-year OS rates (43.3% vs. 49.3%). The PR type was not an independent risk factor for major morbidity or OS. CONCLUSIONS: PR in RPS resection was associated with increased morbidity and mortality with minimal influence on survival. Patients with RPS undergoing PD and DP showed slight differences in terms of safety and OS.

3.
Pest Manag Sci ; 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36193761

RESUMO

BACKGROUND: Plant bacterial diseases have seriously affected the yield and quality of crops, among which rice bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae has seriously affected the yield of rice. As plant-pathogenic bacteria gradually become resistant to existing bactericides, it is necessary to find effective bactericides with novel structures. RESULTS: Herein, a series of compounds containing quinazolin-4(3H)-one and disulfide moieties were designed and synthesized using a facile synthetic method. The bioassay results revealed that most target compounds possessed noticeable antibacterial activity against Xanthomonas oryzae pv. oryzae. Particularly, compound 2-(butyldisulfanyl) quinazolin-4(3H)-one (1) exhibited remarkable antibacterial activity with the half effective concentration (EC50 ) of 0.52 µg mL-1 . Additionally, compound 1 was confirmed to inhibit the growth of the bacteria, change the bacterial morphology, and increase the level of reactive oxygen species. Proteomics, and RT-qPCR analysis results indicated that compound 1 could downregulate the expression of Pil-Chp histidine kinase chpA encoded by the pilL gene, and the potting experiments proved that compound 1 exhibits significant protective activity against BLB. CONCLUSIONS: Compound 1 may weaken the pathogenicity of Xanthomonas oryzae pv. oryzae by inhibiting the bacterial growth and blocking the pili-mediated twitching motility without inducing the bacterial apoptosis. This study indicates that such derivatives could be a promising scaffold to develop a bacteriostat to control BLB. © 2022 Society of Chemical Industry.

4.
Front Surg ; 9: 956384, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157408

RESUMO

The outcomes of patients with primary retroperitoneal sarcoma (RPS) are significantly superior to those with recurrence. En bloc resection of tumor and adjacent organs is recommended in primary RPS. However, whether en bloc resection of tumor and adjacent organs can benefit recurrent patients or some recurrent patients is unclear. We compared the outcomes of patients with primary RPS, first recurrence (RPS-Rec1), and ≥2 recurrences (≥RPS-Rec2) to evaluate the value and criteria for en bloc resection of tumor and adjacent organs in recurrent cases. We evaluated the safety of en bloc resection of tumor and adjacent organs by assessing operation time, blood loss volume, postoperative morbidities (POM), and efficacy by comparing local recurrence and peritoneal metastasis (LR-PM), distant metastasis, progression-free survival (PFS), and overall survival (OS). A total of 101, 47, and 30 patients with primary RPS, RPS-Rec1, and ≥RPS-Rec2 were included, respectively. Recurrent RPS invaded more adjacent organs and surrounding fat tissue than primary RPS. The operation time, amount of blood loss, incidence of grade III-V POM, LR-PM rate, PFS, and OS in the RPS-Rec1 group were similar to those of the primary group, both of which were significantly superior to those of the ≥RPS-Rec2 group. Macroscopically incomplete resection and high-grade RPS rather than first recurrence were independent risk factors for LR-PM, PFS, and OS. In conclusion, the safety and efficacy of en bloc resection of tumor and adjacent organs in RPS-Rec1 were comparable with those in primary RPS but significantly superior to those of ≥RPS-Rec2. For RPS-Rec1, comparable outcomes to patients with primary RPS can be achieved, particularly in those in whom a macroscopically complete resection is achieved.

5.
Nat Commun ; 13(1): 3857, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35790749

RESUMO

The active-site density, intrinsic activity, and durability of Ni-based catalysts are critical to their application in industrial alkaline water electrolysis. This work develops a kind of promoters, the bixbyite-type lanthanide metal sesquioxides (Ln2O3), which can be implanted into metallic Ni by selective high-temperature reduction to achieve highly efficient Ni/Ln2O3 hybrid electrocatalysts toward hydrogen evolution reaction. The screened Ni/Yb2O3 catalyst shows the low overpotential (20.0 mV at 10 mA cm-2), low Tafel slope (44.6 mV dec-1), and excellent long-term durability (360 h at 500 mA cm-2), significantly outperforming the metallic Ni and benchmark Pt/C catalysts. The remarkable hydrogen evolution activity and stability of Ni/Yb2O3 are attributed to that the Yb2O3 promoter with high oxophilicity and thermodynamic stability can greatly enlarge the active-site density, reduce the energy barrier of water dissociation, optimize the free energy of hydrogen adsorption, and avoid the oxidation corrosion of Ni.

6.
ACS Appl Mater Interfaces ; 14(21): 24509-24517, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35588507

RESUMO

A dumbbell-shaped compound (TPAD) with four 2,4-diaminotriazine moieties as H-bond units and a benzene ring as a bridge group was found to form hydrogen-bonded organic frameworks (HOFs) with strong cyan fluorescence. An energy acceptor, 6,6',6″,6‴-(((benzo[c][1,2,5]thiadiazole-4,7-diylbis-(4,1-phenylene))bis(azanetriyl))tetrakis(benzene-4,1-diyl))tetrakis(1,3,5-triazine-2,4-diamine) (BTAD), with the same molecular skeleton as TPAD and a longer emission wavelength could homogeneously distribute within the framework of TPAD through occupying the locations of TPAD. As a result, two-component HOFs (TC-HOFs) were formed. The nonradiative energy transfer from TPAD as the donor to BTAD as the acceptor happens within frameworks owing to the efficient spectral overlap between the emission of TPAD and the absorption of BTAD. Moreover, the emission wavelengths and colors of TC-HOFs could be easily and continuously modulated by the content of the acceptor. The fluorescence color changed from cyan to orange when the content of BTAD gradually increased. This finding affirms that TC-HOFs with continuously adjustable composition can be constructed from two molecules with the same molecular skeleton, and highly efficient nonradiative energy transfer may happen in porous TC-HOFs. To the best of our knowledge, these TC-HOFs are the first example of TC-HOFs involved in energy transfer.

7.
Updates Surg ; 74(3): 1157-1163, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32602011

RESUMO

Complete resection for retroperitoneal sarcoma (RPS) involving major vessels frequently requires vascular resection and reconstruction. The use of artificial grafts often leads to postoperative vascular graft infection (VGI), which usually requires reoperation and sometimes leads to death. In the present study, the data of RPS patients who underwent contralateral iliac artery (IIA) transposition for reconstruction of the common iliac artery (CIA) after RPS resection from 2015-2019 were retrospectively analyzed. Clinical, intraoperative, and postoperative outcomes were described. Contralateral IIA transposition was performed to reconstruct the CIA after segmental resection in three patients. All patients underwent concomitant organ resection. Colon resection was performed for all patients, nephrectomy was performed for two patients, and segmental resection of the left ureter with transurethral ureterostomy was performed for one patient. Complete resection was achieved in all patients, and microscopic tumor infiltration to the CIA was observed in all patients (tunica adventitia: 2, tunica media: 1). No major complications occurred during the hospital stay. During the follow-up period (6.0-29.1 months), one patient died from tumor recurrence, and the other two patients did not have any evidence of recurrence or metastatic disease at the latest follow-up. The level of lower limb function was favorable (MSTS93 scores: 28-30). The pelvic organ functions, including bowel, bladder, and sexual functions, were not impaired in any of the patients. This novel technique in which contralateral IIA transposition is performed to reconstruct the CIA after RPS resection is simple and reliable and may be a good alternative to artificial grafts.


Assuntos
Implante de Prótese Vascular , Neoplasias Retroperitoneais , Sarcoma , Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Humanos , Artéria Ilíaca/cirurgia , Neoplasias Retroperitoneais/cirurgia , Estudos Retrospectivos , Sarcoma/cirurgia , Stents , Resultado do Tratamento
8.
Front Oncol ; 11: 622282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926236

RESUMO

BACKGROUND: Soft pancreas is widely recognized as an important risk factor for the development of postoperative pancreatic fistula (POPF). Although fatty pancreas (FP) has not been formally defined as a cause of pancreatic fistula, existing research has shown that it can increase the incidence of POPF by increasing pancreatic tenderness; therefore, it may be a potential risk factor. This study aimed to discern whether FP was associated with POPF. METHOD: Two reviewers independently performed literature searches from five electronic databases. According to the established inclusion criteria, we extracted necessary data from the studies that met the criteria for further analysis. We pooled the odds ratios (ORs) from individual studies using a random-effects model to investigate the associations between POPF and the prognosis of FP. RESULT: A total of 11 studies involving 2484 individuals were included. The pooled prevalence of POPF was 18% (95% CI: 12-24%). Body mass index (BMI) was associated with a significantly increased risk of POPF (OR=3.55; 95% CI: 1.83, 6.86; P=0.0002; I²=0). FP was obviously associated with the occurrence of POPF (OR=3.75; 95% CI: 1.64, 8.58; P=0.002; I²=78). CONCLUSION: FP is closely associated with the development of POPF, and the early identification of these high-risk patients can help to reduce the incidence of POPF. SYSTEMATIC REVIEW REGISTRATION: The Registration URL link is (https://www.crd.york.ac.uk/PROSPERO/). The ID is "CRD42021265141".

9.
Cancer Manag Res ; 13: 6157-6167, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34385843

RESUMO

BACKGROUND: Previous studies have shown that nutrition and systemic inflammation plays an essential role in the development of soft tissue sarcoma. However, few studies have explored the association of clinicopathologic features and local recurrence with nutritional and inflammatory markers in retroperitoneal liposarcoma (RPLS). This study sought to evaluate the prognostic value of the preoperative nutritional and inflammatory markers for local recurrence-free survival (LRFS) among surgical RPLS patients. METHODS: The study included 111 RPLS patients who underwent surgery between May 2010 and June 2019 at the Peking University Cancer Hospital Sarcoma Center. Time-dependent receiver operating characteristic (time-ROC) curve analysis was conducted to evaluate the ability of markers to predict LRFS. The associations of the CONUT-FAR score with clinicopathological variables and LRFS were evaluated. RESULTS: In the time-ROC curve analysis, the CONUT-FAR score was superior to other nutritional and inflammatory markers in predicting LRFS. The CONUT-FAR score was the only nutritional and inflammatory marker that independently predicted LRFS in the multivariate analysis, and patients with a high CONUT-FAR score (> 11) showed significantly decreased LRFS. Although the CONUT-FAR score failed to discriminate patients with low grade (G1) (p = 0.327) or undergoing incomplete (R2) resection (p = 0.072), it stratified patients with high grade (G2 and G3) or undergoing complete resection (R0/R1) into subgroups with significantly distinct LRFS (p < 0.001). The CONUT-FAR score also showed good clinical utility among patients with different clinical characteristics. CONCLUSION: The preoperative CONUT-FAR score reflects both nutritional and inflammatory factors and is an effective predictor of LRFS for surgical RPLS patients.

10.
Contrast Media Mol Imaging ; 2021: 7191363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33505228

RESUMO

This study aimed to evaluate the usefulness of maximum standardized uptake value (SUVmax) on 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET/CT) in differentiating the subtypes and tumor grades of retroperitoneal liposarcoma (RPLS). The data of RPLS patients who underwent surgical resection from November 2013 to December 2019 at the sarcoma center of our institute were reviewed. The demographics, clinical features, and SUVmax of 84 patients who underwent preoperative 18F-FDG PET/CT scans were analyzed. Of these, 19 patients (22.6%) were with well-differentiated liposarcoma (WDLPS), 60 patients (71.4%) were with dedifferentiated liposarcoma (DDLPS), and 5 patients (6.0%) were with pleomorphic liposarcoma (PMLPS). The median SUVmax of WDLPS, DDLPS, and PMLPS groups was 2.8 (IQR: 1.9-3.2), 6.2 (IQR: 4.1-11.3), and 4.5 (IQR: 4.0-7.4). The ROC curve suggested 3.8 as an approximate cutoff value of SUVmax for distinguishing WDLPS and non-WDLPS (sensitivity = 0.769; specificity = 0.895). The median SUVmax for FNCLCC Grades 1, 2, and 3 of RPLS was 2.5 (IQR: 1.9-3.2), 4.5 (IQR: 3.2-6.7), and 9.0 (IQR: 6.0-13.3). The ROC curves suggest that SUVmax of ≤3.8 and >5.3 can be used for predicting FNCLCC Grades 1 and 3, respectively. The result showed that 18F-FDG PET/CT exhibited high sensitivity and specificity for identifying the subtypes and FNCLCC grades of RPLS. Additionally, 18F-FDG PET/CT might be a useful complementary imaging modality for guiding suitable biopsy location of RPLS.


Assuntos
Lipossarcoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Retroperitoneais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18/administração & dosagem , Humanos , Lipossarcoma/diagnóstico , Lipossarcoma/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/administração & dosagem , Neoplasias Retroperitoneais/diagnóstico , Neoplasias Retroperitoneais/patologia
11.
Virus Res ; 305: 198553, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34487767

RESUMO

COVID-19 is seriously threatening human health all over the world. A comprehensive understanding of the genetic mechanisms driving the rapid evolution of its pathogen (SARS-CoV-2) is the key to controlling this pandemic. In this study, by comparing the entire genome sequences of SARS-CoV-2 isolates from Asia, Europe and America, and analyzing their phylogenetic histories, we found a lineage derived from a recombination event that likely occurred before March 2020. More importantly, the recombinant offspring has become the dominant strain responsible for more than one-third of the global cases in the pandemic. These results indicated that the recombination might have played a key role in the pandemic of the virus.


Assuntos
COVID-19/epidemiologia , Evolução Molecular , Genoma Viral , Recombinação Homóloga , Mosaicismo , SARS-CoV-2/genética , América/epidemiologia , Ásia/epidemiologia , Sequência de Bases , COVID-19/história , COVID-19/transmissão , COVID-19/virologia , Europa (Continente)/epidemiologia , Genômica/métodos , História do Século XXI , Humanos , Mutação , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/patogenicidade
12.
ACS Cent Sci ; 6(12): 2354-2361, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33376797

RESUMO

Metal-organic frameworks (MOFs) are a class of promising sorbents for effective sequestration of radioactive 99TcO4 - anions. However, their poor stability and slow sorption kinetics in the industrial condition pose a great challenge. Herein, we demonstrate an optimizing strategy via in situ polymerization of ionic liquids (ILs) encapsulated in the pores of MOFs, forming polyILs@MOFs composites with greatly enhanced TcO4 - sequestration compared with the pristine MOFs. Notably, the cross-linked polymerization of ILs facilitates the formation of both the inside ionic filler as the active sites and outside coating as the protective layers of MOFs, which is significantly beneficial to obtain the optimized sorption materials of exceptional stability under extreme conditions (e.g., in 6 M HNO3). The final optimized composite shows fast sorption kinetics (<30 s), good regeneration (>30 cycles), and superior uptake performance for TcO4 - in highly acidic conditions and simulated recycle stream. This strategy opens up a new opportunity to construct the highly stable MOF-based composites and extend their applicability in different fields.

13.
Int J Med Sci ; 17(18): 3073-3081, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173428

RESUMO

Patient-derived xenograft (PDX) models are effective preclinical cancer models that reproduce the tumor microenvironment of the human body. The methods have been widely used for drug screening, biomarker development, co-clinical trials, and personalized medicine. However, the low success rate and the long tumorigenesis period have largely limited their usage. In the present studies, we compared the PDX establishment between hepatocellular cancer (HCC) and metastatic liver cancer (MLC), and identified the key factors affecting the transplantation rate of PDXs. Surgically resected tumor specimens obtained from patients were subcutaneously inoculated into immunodeficient mice to construct PDX models. The overall transplantation rate was 38.5% (20/52), with the HCC group (28.1%, 9/32) being lower than MLC group (56.2%, 9/16). In addition, HCC group took significantly longer latency period than MLC group to construct PDX models. Hematoxylin and eosin staining results showed that the histopathology of all generations in PDX models was similar to the original tumor in all three types of cancer. The transplantation rate of PDX models in HCC patients was significantly associated with blood type (P=0.001), TNM stage (P=0.023), lymph node metastasis (P=0.042) and peripheral blood CA19-9 level (P=0.049), while the transplantation rate of PDX models in MLC patients was significantly associated with tumor size (P=0.034). This study demonstrates that PDX models can effectively reproduce the histological patterns of human tumors. The transplantation rate depends on the type of original tumor. Furthermore, it shows that the invasiveness of the original liver cancer affects the possibility of its growth in immunodeficient mice.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Fígado/patologia , Microambiente Tumoral , Animais , Carcinoma Hepatocelular/cirurgia , Neoplasias Colorretais/cirurgia , Feminino , Hepatectomia , Humanos , Fígado/cirurgia , Neoplasias Hepáticas/cirurgia , Masculino , Camundongos , Pessoa de Meia-Idade , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
Front Oncol ; 10: 548789, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072576

RESUMO

BACKGROUND: En bloc resection of retroperitoneal sarcoma (RPS) with adjacent organs such as pancreatic head and duodenum is challenging for surgeons. This mono-institutional study aims to evaluate the feasibility, safety, and outcome of performing pancreaticoduodenectomy (PD) during RPS resection. METHODS: The clinical data of RPS patients who underwent PD at the Sarcoma Center of Peking University Cancer Hospital from January 2011 to December 2019 was collected and analyzed. RESULTS: Twenty-seven patients out of a total of 264 surgically treated RPS underwent PD. The main pathological subtype was liposarcoma. All patients received concomitant resection of a median of three additional organs (range: 1-5), including 11 patients (40.7%) who underwent inferior vena cava resection and one patient who underwent segmental superior mesenteric-portal vein resection. Microscopic tumor infiltration to the duodenum or pancreas was observed in 81.5% of patients. Major complications occurred in 40.7% of patients; the reoperation rate was 22.2%. One patient (3.7%) died from liver abscess postoperatively. During a median follow-up of 18.9 months, 15 patients (55.6%) developed locally recurrent disease; two patients (7.4%) also had pulmonary metastases additionally. Twelve patients (44.4%) died from local relapse eventually. CONCLUSION: PD during RPS resection is feasible, and it may be necessary to achieve complete resection. However, considering the complexity and risk, it should be performed by an experienced surgical team. The long-term survival benefit of this procedure should be verified by further large-scale multi-institutional studies.

15.
Math Biosci Eng ; 17(3): 2384-2398, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32233541

RESUMO

The universality of M-polynomial paves way towards establishing closed forms of many leading degree-based topological indices as it is done by Hosoya polynomial for distance-based indices. The study of topological indices is recently one of the most active research areas in chemical graph theory. The aim of this paper is to establish closed formulas for M-polynomials of Linear chains of benzene, napthalene, and anthracene graphs. From this polynomial we also compute as many as nine degree-based topological indices for these three chains. Our results will potentially play an important role in pharmacy, drug design, and many other applied areas of molecular sciences.

16.
ACS Appl Mater Interfaces ; 12(13): 15246-15254, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32150370

RESUMO

A porous cationic Ag(I) coordination polymer, [Ag(1,2,4,5-p4b)](SbF6) (TJNU-302) with the ligand 1,2,4,5-p4b (1,2,4,5-tetra(pyridin-4-yl)benzene), is reported that shows high sorption capacity (211 mg g-1) and distribution coefficient Kd (5.8 × 105 mL g-1) as well as outstanding selectivity in 500 times excess of CO32- or PO43- anion for perrhenate removal. TJNU-302 can act as a crystalline turn-off sensor for perrhenate upon UV radiation. In this way, a test paper strip for sensing ReO4- could be produced. In water solution, TJNU-302 shows an efficient fluorescence quenching response to ReO4- ion, with the highest quenching percentage (86%) among all reported ReO4- sensors. These results could be elucidated by the bonding properties of single-crystal structures of TJNU-302 before and after perrhenate sorption, as well as density functional theory (DFT) calculations.

17.
ACS Appl Mater Interfaces ; 11(45): 42375-42384, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31647866

RESUMO

A methodology was developed to design superior sorbents of oxoanions. To integrate the high efficiency of chemisorption, selectivity, and recyclability into one sorbent, understanding the nature of oxoanions-sorbent interactions and the structural evolution of the sorbents is essential. Three cationic Ag(I) coordination polymers (CPs) are synthesized for dichromate (Cr2O72-) removal, and three distinct oxoanion-exchange mechanisms are identified, namely, the replacement, breath, and reconstruction processes, depending on the degree of framework distortion induced by the dichromate-CP interactions. The single crystal to single crystal transformation during the oxoanion exchange has been investigated by using single-crystal X-ray diffraction and energy-dispersive X-ray microanalysis. The replacement process, due to a weak chemisorption, shows excellent recyclability at the cost of reduction of efficiency and selectivity of adsorption. The reconstruction process may achieve a high efficiency and selectivity, but it loses recyclability. Due to the formation of a Ag-O(dichromate) bond and the breathing effect of the framework, the sorbent with the breath mechanism shows both superior efficiency and high recyclability in dichromate removal. The study of perrhenate (ReO4-) removal using the same CPs demonstrates that one CP performing the reconstruction process during dichromate removal turns to the breath process in removal of perrhenate anions. These results of mechanism-property correlation provide an insight into improvement of the methodology to fabricate a superior CP sorbent for oxoanion removal.

18.
Angew Chem Int Ed Engl ; 58(43): 15362-15366, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31441563

RESUMO

The electrochemical nitrogen reduction reaction (NRR) offers an energy-saving and environmentally friendly approach to produce ammonia under ambient conditions. However, traditional catalysts have extremely poor NRR performances because of their low activity and the competitive hydrogen evolution reaction. The high catalytic activity of nanoporous gold (NPG) and the hydrophobicity and molecular concentrating effect of the zeolitic imidazolate framework-8 (ZIF-8) were incorporated in the NPG@ZIF-8 nanocomposite so that the ZIF-8 shell could weaken hydrogen evolution and retard reactant diffusion. A highest Faradaic efficiency of 44 % and an excellent rate of ammonia production of (28.7±0.9) µg h-1 cm-2 were achieved, which are superior to traditional gold nanoparticles and NPG. Moreover, the composite catalyst shows high electrochemical stability and selectivity (98 %). The superior NRR performance makes NPG@ZIF-8 one of the most promising water-based NRR electrocatalysts for ammonia production.

19.
Chemistry ; 25(49): 11474-11480, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31119797

RESUMO

CO2 is considered as the primary greenhouse gas, resulting in a series of serious environmental problems that affect people's life and health. Carbon capture and sequestration has been implemented as one of the most appealing pathways to control and use CO2 . Here, we rationally integrate various functional sites within the confined nanospace of a microporous metal-organic framework (MOF) material, which is constructed by mixed-ligand strategy based on metal-adeninate vertices. It not only exhibits excellent stability but also can efficiently transform CO2 and epoxides to cyclic carbonates under mild and cocatalyst-free conditions. Additionally, this catalyst shows extraordinary recyclability for the CO2 cycloaddition reaction.

20.
ACS Appl Mater Interfaces ; 11(17): 15591-15597, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30990300

RESUMO

Self-assembly of resorcin[4]arene-based coordination cages involving more than two resorcin[4]arenes poses significant challenges for the requirements of suitable functionalized resorcin[4]arene ligands and metals. Here, we report an unusual example of a metal-coordinated, resorcin[4]arene-based molecular trimer (1-NO3), composed of three resorcin[4]arenes and three Cd(II) cations. In particular, 1-NO3 features efficient and selective removal of environmentally toxic dichromate (Cr2O72-) anions. Moreover, the Knoevenagel condensation reaction was also explored by using 1-NO3 as an efficient heterogeneous catalyst.

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