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1.
Circulation ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39229700

RESUMO

BACKGROUND: Renal denervation (RDN) can lower blood pressure (BP) in patients with hypertension in both the presence and absence of medication. This is the first sham-controlled trial investigating the safety and efficacy of RDN in China. METHODS: This prospective, multicenter, randomized, patient- and outcome-assessor-blinded, sham-controlled trial investigated radiofrequency RDN in patients with hypertension on standardized triple antihypertensive therapy. Eligible patients were randomized 1:1 to undergo RDN using a multi-electrode radiofrequency catheter (Iberis; AngioCare, Shanghai, China) or a sham procedure. The primary efficacy outcome was the between-group difference in baseline-adjusted change in mean 24-hour ambulatory systolic BP from randomization to 6 months. RESULTS: Of 217 randomized patients (mean age, 45.3±10.2 years; 21% female), 107 were randomized to RDN and 110 were randomized to sham control. At 6 months, there was a greater reduction in 24-hour systolic BP in the RDN (-13.0±12.1 mm Hg) compared with the sham control group (-3.0±13.0 mm Hg; baseline-adjusted between-group difference, -9.4 mm Hg [95% CI, -12.8 to -5.9]; P<0.001). Compared with sham, 24-hour diastolic BP was lowered by -5.0 mm Hg ([95% CI, -7.5 to -2.4]; P<0.001) 6 months after RDN, and office systolic and diastolic BP was lowered by -6.4 mm Hg ([95% CI, -10.5 to -2.3]; P=0.003) and -5.1 mm Hg ([95% CI, -8.2 to -2.0]; P=0.001), respectively. One patient in the RDN group experienced an access site complication (hematoma), which resolved without sequelae. No other major device- or procedure-related safety events occurred through follow-up. CONCLUSIONS: In this trial of Chinese patients with uncontrolled hypertension on a standardized triple pharmacotherapy, RDN was safe and reduced ambulatory and office BP at 6 months compared with sham. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT02901704.

2.
Inorg Chem ; 63(36): 16605-16609, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39193927

RESUMO

The development of novel adsorption materials is of significance for the efficient and low-energy purification of acetylene (C2H2). Emerging metal-organic framework (MOF) adsorbents demonstrate great application prospects in the field of gas adsorption and separation. Herein, we synthesized a Eu-MOF asymmetrically modified with cyclopentadienyl cobalt exhibiting two different types of cages, denoted as UPC-119. Adsorption isotherms and dynamic breakthrough curves confirm its potential in C2H2/CO2 separation, which is further evidenced by theoretical simulations. The high adsorption capacity and low adsorption enthalpy render UPC-119 as a promising adsorbent for C2H2/CO2 separation with ease of regeneration.

3.
Phys Chem Chem Phys ; 26(34): 22739-22751, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39162041

RESUMO

The study of energy correlations in catalytic reactions plays a pivotal role in guiding catalyst development. This paper focuses on the investigation of energy linear relationships in methanol synthesis from CO2 hydrogenation on copper surfaces, systematically exploring energy parameters including activation energy, reaction energy and adsorption energy. A comparative analysis of the adsorption characteristics and reaction parameters in the formate, formic acid and reverse water-gas shift pathways is conducted, laying the data foundation for subsequent linear studies. Then, descriptors are extracted from electronic, energetic and structural information and further integrated using the sure independence screening and sparsifying operator (SISSO) method to establish an energy description paradigm characterized by interpretability and accuracy. Additionally, reactions are further categorized based on hydrogenation types to mitigate the adverse effects of redundant data points. Finally, the summarized reaction descriptors are extended to Cu-based alloy systems to highlight the rationality and transferability of the developed descriptors.

4.
Phys Chem Chem Phys ; 26(28): 19088-19104, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38842113

RESUMO

The application of density functional theory (DFT) has enriched our understanding of methanol synthesis through CO2 hydrogenation on Cu-based catalysts. However, variations in catalytic performance under different metal doping conditions have hindered the development of universal catalytic principles. To address these challenges, we systematically investigated the scaling relationships of adsorption energy among different reaction intermediates on pure Cu, Au-Cu, Ni-Cu, Pt-Cu, Pd-Cu and Zn-Cu models. Additionally, by summing the respective adsorption energies of two separate species, we have developed a dual intermediate descriptor of CHO&CH3OH, capable of achieving computational accuracy on par with DFT results using the multiple linear regression method, all the while enabling the rapid prediction of thermodynamic properties at various stages of methanol synthesis. This method facilitates a better understanding of the coupling mechanisms between energy and linear expressions on copper-based substrates, and the universal linear criterion can be applied to other catalytic systems, with the aim of pursuing potential catalysts having both high efficiency and low cost.

5.
Angew Chem Int Ed Engl ; 63(33): e202407240, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38839564

RESUMO

One-step purification of ethylene from ternary mixtures (C2H2, C2H4, and C2H6) can greatly reduce the energy consumption of the separation process, but it is extremely challenging. Herein, we use crystal engineering and reticular chemistry to introduce unsaturated bonds (ethynyl and alkyne) into ligands, and successfully design and synthesized two novel Zr-MOCs (ZrT-1-ethenyl and ZrT-1-alkyne). The introduction of carbon-carbon unsaturated bonds provides abundant adsorption sites within the framework while modulating the pore window size. Comprehensive characterization techniques including single crystal and powder X-ray diffraction, as well as electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) confirm that ZrT-1-ethenyl and ZrT-1-alkyne possess an isostructural framework with ZrT-1 and ZrT-1-Me, respectively. Adsorption isotherms and breakthrough experiments combined with theoretical calculations demonstrate that ZrT-1-ethenyl can effectively remove trace C2H2 and C2H6 in C2H4 and achieve separation of C2H2 from C2H4 and CO2. ZrT-1-ethenyl can also directly purify C2H4 in liquid solutions. This work provides a benchmark for MOCs that one-step purification of ethylene from ternary mixtures.

6.
J Am Chem Soc ; 145(29): 15848-15858, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37436791

RESUMO

Membrane-based technologies can provide cost-effective and energy-efficient methods for various separation processes. The key goal is to develop materials with uniform, tunable, and well-defined subnanometer-scale channels. Suitable membrane materials should have high selectivity and permeance and can be manufactured in a robust and scalable fashion. Here, we report the construction of sub-1 nm intercrystalline channels with such characteristics and elucidate their transport properties. These channels are formed by assembling 3D aluminum formate crystals during the amorphous-to-crystalline transformation process. By controlling the transformation time, the channel size can be tuned from the macroscopic scale to nanometer scale. The resulting membranes exhibit tailored selectivity and permeance, with molecular weight cutoffs ranging from around 300 Da to approximately 650 Da, and ethanol permeance ranging from 0.8 to 22.0 L m-2 h-1 bar-1. We further show that liquid flow through these channels changes from viscosity-dominated continuum flow to subcontinuum flow, which can be described by a modified Hagen-Poiseuille model. Our strategy provides a new scalable platform for applications that commonly exploit nanoscale mass transport.

7.
Small ; 19(44): e2304771, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37394703

RESUMO

Nonplanar porphyrins with out-of-plane distortions play crucial roles in many biological functions and chemical applications. The artificial construction of nonplanar porphyrins usually involves organic synthesis and modification, which is a highly comprehensive approach. However, incorporating porphyrins into guest-stimulated flexible systems allows to manipulate the porphyrin distortion through simple ad/desorption of guest molecules. Here, a series of porphyrinic zirconium metal-organic frameworks (MOFs) is reported that exhibit guest-stimulated breathing behavior. X-Ray diffraction analysis and skeleton deviation plots confirm that the material suffers from porphyrin distortion to form a ruffled geometry under the desorption of guest molecules. Further investigation reveals that not only the degree of nonplanarity can be precisely manipulated but also the partial distortion of porphyrin in a single crystal grain can be readily achieved. As Lewis acidic catalyst, the MOF with nonplanar Co-porphyrin exhibits active properties in catalyzing CO2 /propylene oxide coupling reactions. This porphyrin distortion system provides a powerful tool for manipulating nonplanar porphyrins in MOFs with individual distortion profiles for various advanced applications.

8.
Int J Behav Nutr Phys Act ; 20(1): 59, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198574

RESUMO

BACKGROUND: Research on the association of physical activity and sedentary time with dementia is accumulating, though elusive, and the interaction effects of the two remain unclear. We analysed the joint associations of accelerometer-measured physical activity and sedentary time with risk of incident dementia (all-cause dementia, Alzheimer's disease and vascular dementia). METHODS: A total of 90,320 individuals from the UK Biobank were included. Accelerometer-measured total volume of physical activity (TPA) and sedentary time were measured at baseline and dichotomised by median (low TPA [< 27 milli-gravity (milli-g)], high TPA [≥ 27 milli-g]; low sedentary time [< 10.7 h/day], high sedentary time [≥ 10.7 h/day]). Cox proportional hazards models were used to evaluate the joint associations with incident dementia on both additive and multiplicative scales. RESULTS: During a median follow-up of 6.9 years, 501 cases of all-cause dementia were identified. Higher TPA was associated with a lower risk of all-cause dementia, Alzheimer's disease and vascular dementia; the multivariate adjusted hazard ratios (HRs) (95% CI) per 10 milli-g increase were 0.63 (0.55-0.71), 0.74 (0.60-0.90) and 0.69 (0.51-0.93), respectively. Sedentary time was only found to be linked to all-cause dementia, and the HR for high sedentary time was 1.03 (1.01-1.06) compared with that for low sedentary time. No additive and multiplicative relationship of TPA and sedentary time to incident dementia was found (all P values > 0.05). CONCLUSION: Higher TPA level was related to a lower risk of incident dementia irrespective of sedentary time, which highlighted the implication of promoting physical activity participation to counteract the potential detrimental effect of sedentary time on dementia.


Assuntos
Doença de Alzheimer , Demência Vascular , Humanos , Estudos de Coortes , Doença de Alzheimer/epidemiologia , Comportamento Sedentário , Bancos de Espécimes Biológicos , Estudos Prospectivos , Exercício Físico , Acelerometria , Reino Unido/epidemiologia , Fatores de Risco
9.
Inorg Chem ; 62(9): 3722-3726, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36802567

RESUMO

The development of high-performance adsorbents is critical for the low-energy separation of acetylene. Herein, we synthesized an Fe-MOF (MOF, metal-organic framework) with U-shaped channels. The adsorption isotherms of C2H2, C2H4, and CO2 show that the adsorption capacity of acetylene is significantly larger than that of the other two gases. Meanwhile, the actual separation performance was verified by breakthrough experiments, indicating the potential to separate C2H2/CO2 and C2H2/C2H4 mixtures at normal temperatures. Grand Canonical Monte Carlo (GCMC) simulation demonstrates that the framework with U-shaped channels interacts more strongly with C2H2 than with C2H4 and CO2. The high C2H2 uptake and low adsorption enthalpy highlight Fe-MOF as a promising candidate for C2H2/CO2 separation with a low regeneration energy.

10.
J Phys Chem A ; 127(25): 5435-5445, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37319364

RESUMO

The concern of energy and the environment provides great inducement for fundamental research on the mechanisms of oxidation of char-bound nitrogen (char(N)). In the present study, based on the armchair(N) model, we investigated its reaction mechanism at an atomistic level and with a comprehensive study of the effect of the model surface. Several pathways are found by density functional theory (DFT) calculations for the oxidation of armchair(N). The main gaseous species released during the oxidation are NO, HCN, CO, and CO2. The evaluated optimal reaction pathways are selected to investigate the model-dependent reactivity. According to our calculations, the oxidation of the simplified top armchair(N) model (TM) will be much more competitive than that of the simplified edge armchair(N) model (EM). In the route giving NO, the decreased stability of the intermediates makes the reaction of TM more favorable. In the route giving HCN, the described reduced mechanism and the larger exothermicity and lower highest-energy transition state will be responsible for the priority. Further analysis of the kinetics gives the evidence for the competitiveness: the rate constants for most of the steps of the TM, such as HCN desorption, surface bond dissociation, ring closure and opening, and oxygen insertion and migration, are higher than that of the EM. Therefore, a conclusion can be drawn that the oxidation of the armchair(N) will mainly take place from the top surface rather than the edge surface. The results can be used to supplement present understanding of the oxidation of armchair structure, which is extremely crucial for the development of the kinetics model to better predict the NOx emissions during the air-staged combustion.

11.
J Phys Chem A ; 127(35): 7383-7399, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37615481

RESUMO

Systematic DFT calculations of model coal-pyrrole derivatives substituted by different functional groups are carried out. The N-H bond dissociation energies (N-H BDEs) and H-transfer activation energies (H-TAEs) of pyrrole derivatives are fully evaluated to elucidate the effect of the type of substituents and their position on the molecular reactivity. The results indicate that compounds substituted with electron-donating groups (EDGs) are more prone to pyrolysis while those substituted with electron-withdrawing groups (EWGs) are difficult to pyrolyze. Furthermore, quantitative structure-property relationship (QSPR) models for N-H BDEs and H-TAEs about pyrrole derivatives are built with multiple linear regression (MLR) and support vector machine (SVM). The final results show that the SVM-QSPR model has better fitness, prediction, and robustness, while the MLR-QSPR model can express the physical meaning better. The effects of functional groups on pyrolysis are clarified by the models presented in this paper, which will support the optimization of ultra-low NOx combustion.

12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 22-27, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36861150

RESUMO

Objective To analyze the risk factors and build a clinical prediction model for hemodynamic depression (HD) after carotid artery stenting (CAS). Methods A total of 116 patients who received CAS in the Department of Vascular Surgery,Drum Tower Clinical College of Nanjing Medical University and the Department of Vascular Surgery,the Affiliated Suqian First People's Hospital of Nanjing Medical University from January 1,2016 to January 1,2022 were included in this study.The patients were assigned into a HD group and a non-HD group.The clinical baseline data and vascular disease characteristics of each group were collected,and multivariate Logistic regression was employed to identify the independent predictors of HD after CAS and build a clinical prediction model.The receiver operating characteristic (ROC) curve was drawn,and the area under the ROC curve (AUC) was calculated to evaluate the predictive performance of the model. Results The HD group had lower proportions of diabetes (P=0.014) and smoking (P=0.037) and higher proportions of hypertension (P=0.031),bilateral CAS (P=0.018),calcified plaque (P=0.001),eccentric plaque (P=0.003),and the distance<1 cm from the minimum lumen level to the carotid bifurcation (P=0.009) than the non-HD group.The age,sex,coronary heart disease,symptomatic carotid artery stenosis,degree of stenosis,and length of lesions had no statistically significant differences between the HD group and the non-HD group (all P>0.05).Based on the above predictive factors,a clinical prediction model was established,which showed the AUC of 0.807 and the 95% CI of 0.730-0.885 (P<0.001).The model demonstrated the sensitivity of 62.7% and the specificity of 87.7% when the best cut-off value of the model score reached 12.5 points. Conclusions Diabetes,smoking,calcified plaque,eccentric plaque,and the distance<1 cm from the minimum lumen level to the carotid bifurcation are independent predictors of HD after CAS.The clinical prediction model built based on the above factors has good performance in predicting the occurrence of HD after CAS.


Assuntos
Estenose das Carótidas , Humanos , Depressão , Modelos Estatísticos , Prognóstico , Stents , Hemodinâmica , Placa Amiloide
13.
J Endovasc Ther ; 29(1): 32-41, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34727761

RESUMO

PURPOSE: The purpose of this study was to evaluate the association between the distance from the primary intimal tear (PIT) to the left subclavian artery (LSA) (PIT-LSA distance) and the risk of aortic enlargement after thoracic endovascular aortic repair (TEVAR). METHODS: This is a retrospective cohort study. A total of 228 patients were reviewed from the database of the Registry Of type B aortic dissection with the Utility of STent graft (ROBUST) study performed from January 1, 2011, to December 31, 2016. Of them, 196 patients were eligible for analysis. The PIT-LSA distance was defined as the length from the distal edge of the LSA orifice to the proximal edge of the PIT along the centerline of the true lumen. According to the border between zone 3 and zone 4 of the Ishimaru classification, patients were divided into group A (n = 117, PIT-LSA distance ≤ 2 cm) and group B (n = 79, PIT-LSA distance > 2 cm). Thoracic aortic enlargement (TAE) was defined as a thoracic aortic volume increase of ≥20%. Multivariate Cox regression was used to estimate the association between the PIT-LSA distance and risk of TAE after TEVAR. RESULTS: The mean age was 52.3 ± 11.6 years, and 88.8% of patients were male. There were no significant differences between groups in demographic and baseline characteristics. The PIT-LSA distance was 1.1 cm (range, -1.6 to 2.0 cm) in group A, and 2.9 cm (range, 2.1-12.6 cm) in group B. TAE occurred in 27 patients in group A, and 6 in group B. The mean follow-up was 12.4 months (range, 0.10-83.1 months) in group A, and 12.63 months (range, 0.10-82.77 months) in group B. The cumulative 12- and 24-month rates of freedom from TAE were 79.0% and 71.3% in group A, versus 92.5% and 92.5% in group B, respectively. Multivariate Cox regression analysis revealed that the PIT-LSA distance was an independent predictor of TAE after TEVAR (adjusted hazard ratio, 0.66; 95% confidence interval, 0.48-0.90; p = 0.009). CONCLUSION: Patients with a more proximal PIT location have a higher incidence of thoracic aortic enlargement after TEVAR. The location of the PIT in relation to the LSA can be used to identify patients who need closed surveillance after TEVAR or early preemptive intervention.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Fatores de Tempo , Resultado do Tratamento
14.
Ecotoxicol Environ Saf ; 242: 113835, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35816845

RESUMO

BACKGROUND: Epidemiological evidence regarding the associations between long-term exposure to air pollution and risk of incident inflammatory bowel disease (IBD) is scant. OBJECTIVES: We examined the associations of various specific air pollutants with the risk of incident ulcerative colitis and Crohn's disease, two subtypes of IBD, among middle and old aged adults in the UK. We also explored potential susceptible subgroups. METHODS: We used data from the UK Biobank study. Information on air pollution, including PM2.5, PM2.5-10, PM10 as well as NO2 and NOx were estimated using the Land Use Regression model. Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: After a median follow-up of 11.7 years, 1872 incident ulcerative colitis and 865 incident Crohn's disease cases were identified among 455,210 IBD-free participants. HRs (95% CIs) of ulcerative colitis associated with each 1 interquartile range (IQR) increase in PM2.5, PM2.5-10, PM10, NO2, and NOx were 1.06 (1.01, 1.12), 1.03 (0.99, 1.08), 1.09 (1.03, 1.16), 1.12 (1.07, 1.19), and 1.07 (1.02, 1.12), respectively. The associations between all the air pollutants and risk of Crohn's disease were null. Smoking status and sex appeared to respectively modify the associations between some air pollutants and risk of ulcerative colitis and Crohn's disease. CONCLUSION: Long-term exposure to various air pollutants was associated with the risk of incident ulcerative colitis but not Crohn's disease, highlighting the importance of developing environmental health strategy to reduce the burden of ulcerative colitis.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Colite Ulcerativa/epidemiologia , Doença de Crohn/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Humanos , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Material Particulado/efeitos adversos , Material Particulado/análise
15.
J Am Chem Soc ; 143(42): 17716-17723, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34608802

RESUMO

Membrane technology is attractive for natural gas separation (removing CO2, H2O, and hydrocarbons from CH4) because of membranes' low energy consumption and small environmental footprint. Compared to polymeric membranes, microporous inorganic membranes such as silicoaluminophosphate-34 (SAPO-34) membrane can retain their separation performance under conditions close to industrial requirements. However, moisture and hydrocarbons in natural gas can be strongly adsorbed in the pores of those membranes, thereby reducing the membrane separation performance. Herein, we report the fabrication of a polycrystalline MIL-160 membrane on an Al2O3 substrate by in situ hydrothermal synthesis. The MIL-160 membrane with a thickness of ca. 3 µm shows a remarkable molecular sieving effect in gas separation. Besides, the pore size and environment of the MIL-160 membrane can be precisely controlled using reticular chemistry by regulating the size and functionality of the ligand. Interestingly, the more polar fluorine-functionalized multivariate MIL-160/CAU-10-F membrane exhibits a 10.7% increase in selectivity for CO2/CH4 separation and a 31.2% increase in CO2 permeance compared to those of the MIL-160 membrane. In addition, hydrophobic MIL-160 membranes and MIL-160/CAU-10-F membranes are more resistant to water vapor and hydrocarbons than the hydrophilic SAPO-34 membranes.

16.
Chemistry ; 27(41): 10693-10699, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-33886157

RESUMO

Regulating the structure of metal-organic frameworks (MOFs) by adjusting the ligands reasonably is expected to enhance the interaction of MOFs on special molecules/ions, which has significant application value for the selective adsorption of guest molecules. Herein, two tricarboxylic ligands H3 L-Cl and H3 L-NH2 were designed and synthesized based on the ligand H3 TTCA by replacing part of the benzene rings with C=C bonds and modifying the chlorine and amino groups on the 4-position of the benzene ring. Two 3D Fe-MOFs (UPC-60-Cl and UPC-60-NH2 ) with the new topology types were constructed. As the C=C bonds of the ligands have flexible torsion angles, UPC-60-Cl features three types of irregular 2D channels, while UPC-60-NH2 has a cage with two types of windows on the surface. The synergistic effect of unique channels and modification of functional groups endows UPC-60-Cl and UPC-60-NH2 with high adsorption capacity for organic dyes. Compound UPC-60-Cl shows high adsorption capacity for CV (147.2 mg g-1 ), RHB (100.3 mg g-1 ), and MO (220.9 mg g-1 ), whereas UPC-60-NH2 exhibits selective adsorption of MO (158.7 mg g-1 ). Meanwhile, based on the diverse pore structure and modification of active sites, UPC-60-Cl and UPC-60-NH2 show the selective separation of equimolar C2 H2 /CO2 . Therefore, reasonable regulation of organic ligands plays a significant role in guiding the structure diversification and performance improvement of MOFs.

17.
Ann Vasc Surg ; 71: 56-64, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32949748

RESUMO

BACKGROUND: Abdominal aortic enlargement (AAE) is a commonly seen complication after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). This study assessed the relationship between preoperative abdominal false lumen-perfused small branches (pre-AFLSBs) and risk of AAE after TEVAR for TBAD extending through the abdominal aorta. METHODS: One hundred and eighty-four patients with TBAD who had been treated by TEVAR at 4 hospitals in China were stratified in accordance with median pre-AFLSBs: ≤8 (group A) and >8 (group B). AAE was defined as ≥20% increase in abdominal total aortic volume, measured using imaging software featuring centerline analysis, on most recent postoperative computed tomography angiography relative to preoperative examination. Multivariable Cox proportional hazard regression was used to evaluate the relationship between the number of pre-AFLSBs and the risk of AAE after TEVAR. RESULTS: At median 12.4 months imaging follow-up, AAE was present in 65 patients at higher cumulative rate (log-rank test P < 0.001) in group B, which had more frequent partially thrombosed or patent abdominal false lumen than group A at 6-12 months (P < 0.01) and 12-24 months (P = 0.03) of follow-up. In a multivariable Cox proportional hazard regression model, the number of pre-AFLSBs was independently associated with risk of AAE after TEVAR (hazard ratio [for one increase], 1.10; 95% confidence interval, 1.00-1.21; P = 0.04) after adjustment for age, gender, dissection chronicity, Society for Vascular Surgery risk score, preoperative maximum descending aortic diameter, false lumen status of the abdominal aorta, numbers of false lumen-perfused visceral arteries, abdominal intimal larger tears, and preoperative abdominal intimal small tears, and dissection length and descending aortic length ratio. CONCLUSIONS: The number of pre-AFLSBs was positively associated with the risk of AAE after TEVAR for TBAD extending through the abdominal aorta.


Assuntos
Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Remodelação Vascular , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , China , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
18.
Ann Vasc Surg ; 77: 54-62, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34175415

RESUMO

BACKGROUND: This study was performed to evaluate the nonlinear association of the distal oversizing ratio with distal stent-graft-induced new entry (dSINE) following thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) and to find the optimal value of the distal oversizing ratio for prevention strategy of dSINE. METHODS: Total of 177 patients who underwent TEVAR for TBAD from the Registry Of type B aortic dissection with the Utility of STent graft were retrospectively investigated. Patients were stratified into two groups on the median distal oversizing ratio: lower group (≤16%, n = 88) and higher group (>16%, n = 89). The Kaplan-Meier method was used to estimate the cumulative incidence of dSINE. The multivariate Cox proportional hazards model was used to identify the association of the distal oversizing ratio with dSINE. Restricted cubic smoothing spline plots and two-piecewise regression were used to analyze the possible nonlinear association. RESULTS: Eleven patients developed dSINE (6.21%) during the median follow-up time of 12.37 months (interquartile range, 8.07-18.17 months). An S-shaped association of the distal oversizing ratio with dSINE was identified. When the distal oversizing ratio was ≤40%, the risk of dSINE increased with distal oversizing ratio, and the risk of dSINE was highest when the distal oversizing ratio reached 40% (adjusted HR, 1.09; 95% CI, 1.02-1.17; P = 0.011). A larger distal oversizing ratio over 40% did not generate a greater risk of dSINE (adjusted HR, 0.95; 95% CI, 0.87-1.05; P = 0.455). CONCLUSIONS: This study substantiated previous findings that the dSINE was associated with the increasing distal oversizing ratio. We also found an S-shaped association between the distal oversizing ratio and dSINE after TEVAR for TBAD. The distal oversizing ratio of 40% can be used for stratified management of patients who underwent TEVAR for TBAD.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Idoso , Dissecção Aórtica/diagnóstico por imagem , Aneurisma Aórtico/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , China , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Desenho de Prótese , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
19.
Angew Chem Int Ed Engl ; 60(32): 17338-17343, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33955661

RESUMO

Isoreticular functionalization is a well-elucidated strategy for pore environment tuning and the basis of gas separation performance in extended frameworks. The extension of this approach to discrete porous molecules such as metal-organic cages (MOCs) is conceptually straightforward but hindered by synthetic complications, especially stability concerns. We report the successful isoreticular functionalization of a zirconium MOC with tetrazole moiety by bottom-up synthesis. The title compound (ZrT-1-tetrazol) shows promising C2 H2 /CO2 and C2 H2 /C2 H4 separation performance, as demonstrated by adsorption isotherms, breakthrough experiments, and density functional theory calculations. The design analogy between MOFs and highly stable MOCs may guide the synthesis of novel porous materials for challenging separation applications.

20.
Angew Chem Int Ed Engl ; 60(20): 11350-11358, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33661542

RESUMO

The separation of ethylene (C2 H4 ) from a mixture of ethane (C2 H6 ), ethylene (C2 H4 ), and acetylene (C2 H2 ) at normal temperature and pressure is a significant challenge. The sieving effect of pores is powerless due to the similar molecular size and kinetic diameter of these molecules. We report a new modification method based on a stable ftw topological Zr-MOF platform (MOF-525). Introduction of a cyclopentadiene cobalt functional group led to new ftw-type MOFs materials (UPC-612 and UPC-613), which increase the host-guest interaction and achieve efficient ethylene purification from the mixture of hydrocarbon gases. The high performance of UPC-612 and UPC-613 for C2 H2 /C2 H4 /C2 H6 separation has been verified by gas sorption isotherms, density functional theory (DFT), and experimentally determined breakthrough curves. This work provides a one-step separation of the ternary gas mixture and can further serve as a blueprint for the design and construction of function-oriented porous structures for such applications.

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