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1.
J Hazard Mater ; 435: 129009, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35500344

ABSTRACT

Constructing catalysts with simple structures, uniform effective sites, and excellent performance is crucial for understanding the reaction mechanism of target pollutants. Herein, the single-atom catalyst of Mn-intercalated graphitic carbon nitride (Mn/g-C3N4) was prepared. It was found that the intercalated Mn atoms acted as strong electron donors to effectively tune the electronic structure distribution of the in-situ N atoms, providing a large number of negative potential atomic-scale sites for catalytic reactions. In the detection, the in-situ N atom established an electron bridge for the transient electrostatic trapping of free Pb(II), which induced Pb-N-Mn coordination bonding. Even in g-C3N4-loaded Mn nanoparticles, the N atom was again confirmed to be the interaction site for coupling with Pb. And the MnII-N4-C/MnIV-N4-C cycle actively participated in the electrocatalysis of Pb(II) was confirmed. Moreover, Mn/g-C3N4 achieved highly stable and accurate detection for Pb(II) with a sensitivity of 2714.47 µA·µM-1·cm-2. And excellent reproducibility and specific detection of real water samples made the electrode practical. This study contributes to understanding the changes in the electronic structure of chemically inert substrates after single-atom intercalation and the interaction between contaminants and the microstructure of sensitive materials, providing a guiding strategy for designing highly active electrocatalytic interfaces for accurate electroanalysis.

2.
Braz J Cardiovasc Surg ; 35(3): 346-367, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32549107

ABSTRACT

OBJECTIVE: Results from randomized controlled trials (RCTs) and real-world study (RWS) appear to be discordant. We aimed to investigate whether data derived from RCTs and RWS evaluating long-term all-cause mortality of transcatheter aortic valve implantation (TAVI) versus surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis (AS) were in agreement. METHODS: RCTs or RWS comparing TAVI and SAVR, reporting longterm (≥2-year follow-up) all-cause mortality, were identified. We also carried out subgroup analyses to access the effect in different subgroups. A pre-designated data extraction form including 5 domains and 26 items was used to explore the relationship between RCTs and RWS. Mortality and effect in different subgroups were evaluated using random-effects meta-analyses. RESULTS: Five RCTs (5421 participants, TAVI: 2759, SAVR: 2662) and 33 RWS (20839 participants; TAVI: 6585, SAVR: 14254) were identified. Pooled RCT analysis showed no difference in all-cause mortality between TAVI and SAVR (HR=0.97, 95% CI: 0.88-1.07; P=0.55). In RWS, TAVI was associated with an increased risk of allcause mortality (HR=1.46, 95% CI: 1.26-1.69; P<0.001) compared to SAVR. CONCLUSION: These results highlight the inconsistencies between RCTs and RWS in assessing long-term all-cause mortality in the treatment of AS using TAVI or SAVR, which may be caused by interactions of clinical characteristics or study design. RCTs as well as RWS are both developing and improving; the advantages of one kind of design, measurement and evaluation can and should be thoughtfully referred to the other.


Subject(s)
Aortic Valve Stenosis , Heart Valve Prosthesis Implantation , Heart Valve Prosthesis , Percutaneous Coronary Intervention , Transcatheter Aortic Valve Replacement , Aged , Aged, 80 and over , Aortic Valve/surgery , Aortic Valve Stenosis/surgery , Female , Humans , Male , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome
3.
Rev. bras. cir. cardiovasc ; Rev. bras. cir. cardiovasc;35(3): 346-367, May-June 2020. tab, graf
Article in English | Sec. Est. Saúde SP, LILACS | ID: biblio-1137271

ABSTRACT

Abstract Objective: Results from randomized controlled trials (RCTs) and real-world study (RWS) appear to be discordant. We aimed to investigate whether data derived from RCTs and RWS evaluating long-term all-cause mortality of transcatheter aortic valve implantation (TAVI) versus surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis (AS) were in agreement. Methods: RCTs or RWS comparing TAVI and SAVR, reporting longterm (≥2-year follow-up) all-cause mortality, were identified. We also carried out subgroup analyses to access the effect in different subgroups. A pre-designated data extraction form including 5 domains and 26 items was used to explore the relationship between RCTs and RWS. Mortality and effect in different subgroups were evaluated using random-effects meta-analyses. Results: Five RCTs (5421 participants, TAVI: 2759, SAVR: 2662) and 33 RWS (20839 participants; TAVI: 6585, SAVR: 14254) were identified. Pooled RCT analysis showed no difference in all-cause mortality between TAVI and SAVR (HR=0.97, 95% CI: 0.88-1.07; P=0.55). In RWS, TAVI was associated with an increased risk of allcause mortality (HR=1.46, 95% CI: 1.26-1.69; P<0.001) compared to SAVR. Conclusion: These results highlight the inconsistencies between RCTs and RWS in assessing long-term all-cause mortality in the treatment of AS using TAVI or SAVR, which may be caused by interactions of clinical characteristics or study design. RCTs as well as RWS are both developing and improving; the advantages of one kind of design, measurement and evaluation can and should be thoughtfully referred to the other.


Subject(s)
Humans , Male , Female , Aged , Aged, 80 and over , Aortic Valve Stenosis/surgery , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation , Percutaneous Coronary Intervention , Transcatheter Aortic Valve Replacement , Aortic Valve/surgery , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome
4.
Braz. j. microbiol ; Braz. j. microbiol;42(1): 410-414, Jan.-Mar. 2011. ilus
Article in English | LILACS | ID: lil-571415

ABSTRACT

This study demonstrated that the bacteria could adsorb Fe3+ and reduce Fe3+ to Fe2+. Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe3+ acts through the formation of hydroxyl free radicals.


Subject(s)
Anti-Bacterial Agents/analysis , Iron Bacteria/analysis , Ions/analysis , Iron Chelating Agents/analysis , Siderophores/analysis , Methods , Methods
5.
Braz J Microbiol ; 42(1): 410-4, 2011 Jan.
Article in English | MEDLINE | ID: mdl-24031647

ABSTRACT

This study demonstrated that the bacteria could adsorb Fe(3+) and reduce Fe(3+) to Fe(2+). Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe(3+) acts through the formation of hydroxyl free radicals.

6.
Article in English | VETINDEX | ID: vti-444674

ABSTRACT

This study demonstrated that the bacteria could adsorb Fe3+ and reduce Fe3+ to Fe2+. Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe3+ acts through the formation of hydroxyl free radicals.

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