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1.
PLoS Biol ; 22(3): e3002514, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38483978

RESUMEN

The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a system is a powerful tool in gene editing; however, crRNA-DNA mismatches might induce unwanted cleavage events, especially at the distal end of the PAM. To minimize this limitation, we engineered a hyper fidelity AsCas12a variant carrying the mutations S186A/R301A/T315A/Q1014A/K414A (termed HyperFi-As) by modifying amino acid residues interacting with the target DNA and crRNA strand. HyperFi-As retains on-target activities comparable to wild-type AsCas12a (AsCas12aWT) in human cells. We demonstrated that HyperFi-As has dramatically reduced off-target effects in human cells, and HyperFi-As possessed notably a lower tolerance to mismatch at the position of the PAM-distal region compared with the wild type. Further, a modified single-molecule DNA unzipping assay at proper constant force was applied to evaluate the stability and transient stages of the CRISPR/Cas ribonucleoprotein (RNP) complex. Multiple states were sensitively detected during the disassembly of the DNA-Cas12a-crRNA complexes. On off-target DNA substrates, the HyperFi-As-crRNA was harder to maintain the R-loop complex state compared to the AsCas12aWT, which could explain exactly why the HyperFi-As has low off-targeting effects in human cells. Our findings provide a novel version of AsCas12a variant with low off-target effects, especially capable of dealing with the high off-targeting in the distal region from the PAM. An insight into how the AsCas12a variant behaves at off-target sites was also revealed at the single-molecule level and the unzipping assay to evaluate multiple states of CRISPR/Cas RNP complexes might be greatly helpful for a deep understanding of how CRISPR/Cas behaves and how to engineer it in future.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Humanos , Sistemas CRISPR-Cas/genética , ARN Guía de Sistemas CRISPR-Cas , Endonucleasas/genética , Endonucleasas/metabolismo , ADN/genética
2.
PLoS Biol ; 22(5): e3002619, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38814985

RESUMEN

The CRISPR-associated endonuclease Cas12a has become a powerful genome-editing tool in biomedical research due to its ease of use and low off-targeting. However, the size of Cas12a severely limits clinical applications such as adeno-associated virus (AAV)-based gene therapy. Here, we characterized a novel compact Cas12a ortholog, termed EbCas12a, from the metagenome-assembled genome of a currently unclassified Erysipelotrichia. It has the PAM sequence of 5'-TTTV-3' (V = A, G, C) and the smallest size of approximately 3.47 kb among the Cas12a orthologs reported so far. In addition, enhanced EbCas12a (enEbCas12a) was also designed to have comparable editing efficiency with higher specificity to AsCas12a and LbCas12a in mammalian cells at multiple target sites. Based on the compact enEbCas12a, an all-in-one AAV delivery system with crRNA for Cas12a was developed for both in vitro and in vivo applications. Overall, the novel smallest high-fidelity enEbCas12a, this first case of the all-in-one AAV delivery for Cas12a could greatly boost future gene therapy and scientific research.


Asunto(s)
Sistemas CRISPR-Cas , Dependovirus , Edición Génica , Vectores Genéticos , Dependovirus/genética , Humanos , Edición Génica/métodos , Vectores Genéticos/genética , Animales , Células HEK293 , Terapia Genética/métodos , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Asociadas a CRISPR/genética , Ratones , Endodesoxirribonucleasas/metabolismo , Endodesoxirribonucleasas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(6): e2215900120, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36735757

RESUMEN

Antiaromaticity is extended from aromaticity as a complement to describe the unsaturated cyclic molecules with antiaromatic destabilization. To prepare antiaromatic species is a particularly challenging goal in synthetic chemistry because of the thermodynamic instability of such molecules. Among that, both Hückel and Möbius antiaromatic species have been reported, whereas the Craig one has not been realized to date. Here, we report the first example of planar Craig antiaromatic species. Eight Craig antiaromatic compounds were synthesized by deprotonation-induced reduction process and were fully characterized as follows. Single-crystal X-ray crystallography showed that these complexes have planar structures composed of fused five-membered rings with clearly alternating carbon-carbon bond lengths. In addition, proton NMR (1H NMR) spectroscopy in these structures showed distinctive upfield shifts of the proton peaks to the range of antiaromatic peripheral hydrogens. Experimental spectroscopy observations, along with density-functional theory (DFT) calculations, provided evidence for the Craig antiaromaticity of these complexes. Further study experimentally and theoretically revealed that the strong exothermicity of the acid-base neutralization process was the driving force for this challenging transformation forming Craig antiaromatic species. Our findings complete a full cycle of aromatic chemistry, opening an avenue for the development of new class of antiaromatic systems.

4.
Small ; 20(33): e2401172, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38552220

RESUMEN

Fabricating covalent organic framework (COF) membranes through the pre-assembly of nanosheets with different properties may open a novel avenue to the fabrication of advanced 2D membranes. Herein, COF membranes are fabricated using oppositely-charged COF nanosheets (CONs). Negatively-charged CONs and positively-charged CONs are pre-assembled through simple physical mixing, yielding the CONs with an aspect ratio of exceeding 10 000, which are assembled into three kinds of COF membranes. The optimal membranes exhibit the highest desalination performance with permeation flux of 132.66 kg m-2 h-1, salt rejection of 99.99%, and superior long-term operation stability.

5.
BMC Psychiatry ; 24(1): 515, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030588

RESUMEN

BACKGROUND: The relationships between BUNCr (blood urea nitrogen and creatinine ratio) and cognitive function, as well as depressive symptoms, remain unclear. We aim to investigate the association between BUNCr and cognition, as well as depressive symptoms, and to identify the mechanisms underlying these relationships. METHODS: We utilized data from the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2020. Cognitive function was assessed using the Telephone Interview of Cognitive Status (TICS) scale, while depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10). We employed multivariate linear regression models to examine the association between BUNCr and cognitive function, as well as depressive symptoms. Additionally, causal mediation analysis was conducted to identify potential mediation effects of depressive symptoms between BUNCr and cognition. RESULTS: We observed a negative association between BUNCr and cognitive function (coefficient: -0.192; 95% confidence interval [CI]: -0.326 ∼ -0.059) and a positive relationship between BUNCr and depressive symptoms (coefficient: 0.145; 95% CI: 0.006 ∼ 0.285). In addition, the causal mediation analysis revealed that depressive symptoms (proportion mediated: 7.0%) significantly mediated the association between BUNCr and cognition. CONCLUSION: Our study has unveiled that BUNCr is inversely associated with cognitive function and positively linked to depressive symptoms. Moreover, we found that depressive symptoms significantly mediated the association between BUNCr and cognition. These findings provide new evidence and insights for the prevention and management of cognitive function and dementia.


Asunto(s)
Nitrógeno de la Urea Sanguínea , Cognición , Creatinina , Depresión , Humanos , Depresión/sangre , Depresión/psicología , Masculino , Estudios Longitudinales , Femenino , Anciano , Persona de Mediana Edad , China/epidemiología , Creatinina/sangre , Cognición/fisiología , Análisis de Mediación , Disfunción Cognitiva/sangre
6.
Orthod Craniofac Res ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39137241

RESUMEN

OBJECTIVES: This study aims to compare the achieved and predicted root movements in adults after four first-premolar extractions and Invisalign treatment. MATERIALS AND METHODS: Thirty-three consecutive adults (22 Class I, 9 Cusp-to-cusp Class II and 2 Cusp-to-cusp Class III) from a single clinical division who completed the first series of aligners after premolar extractions were included in this retrospective study. A pretreatment cone-beam computed tomography model was registered onto the pretreatment surface-scanned dental model (SSDM) to locate the pretreatment root apices of the whole dentition. These were copied and transferred to the predicted and achieved post-treatment SSDMs to acquire the locations of the predicted and achieved post-treatment root apices. The differences between predicted and achieved root movements (DPARMs) were tested using the paired t-test or Wilcoxon signed rank test. RESULTS: In the anteroposterior direction, posterior root movements of maxillary and mandibular anterior teeth were poorly achieved (3.24-5.74 mm DPARMs, p < .05). In the vertical direction, roots of maxillary anterior teeth achieved greater intrusion (0.70-0.93 mm DPARMs, p < .05), while those of mandibular incisors achieved less intrusion (0.57-0.65 mm DPARMs, p < .05) than predicted. In the mediolateral direction, lateral incisor roots did not move distally (-0.65 to -0.96 mm DPARMs, p < .05), while those of canines did not move buccally, compared with the prediction (-0.75 mm DPARMs, p < .05). CONCLUSIONS: In the four first-premolar extraction treatments with Invisalign, root movements were not achieved as predicted, particularly for anterior teeth in the anteroposterior direction.

7.
Cardiovasc Diabetol ; 22(1): 165, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37403082

RESUMEN

BACKGROUND: Stress hyperglycemia was positively associated with poor prognosis in individuals with acute myocardial infarction (AMI). However, admission glucose and stress hyperglycemia ratio (SHR) may not be the best indicator of stress hyperglycemia. We performed this study to evaluate the comparative prognostic value of different measures of hyperglycemia (fasting SHR, fasting plasma glucose [FPG], and hemoglobin A1c [HbA1c]) for in-hospital mortality in AMI patients with or without diabetes. METHODS: In this prospective, nationwide, multicenter China Acute Myocardial Infarction (CAMI) registry, 5,308 AMI patients including 2081 with diabetes and 3227 without diabetes were evaluated. Fasting SHR was calculated using the formula [(first FPG (mmol/l))/(1.59×HbA1c (%)-2.59)]. According to the quartiles of fasting SHR, FPG and HbA1c, diabetic and non-diabetic patients were divided into four groups, respectively. The primary endpoint was in-hospital mortality. RESULTS: Overall, 225 (4.2%) patients died during hospitalization. Individuals in quartile 4 had a significantly higher rate of in-hospital mortality compared with those in quartile 1 in diabetic cohort (9.7% vs. 2.0%; adjusted odds ratio [OR] 4.070, 95% CI 2.014-8.228) and nondiabetic cohort (8.8% vs. 2.2%; adjusted OR 2.976, 95% CI 1.695-5.224). Fasting SHR was also correlated with higher in-hospital mortality when treated as a continuous variable in diabetic and nondiabetic patients. Similar results were observed for FPG either as a continuous variable or a categorical variable. In addition, fasting SHR and FPG, rather than HbA1c, had a moderate predictive value for in-hospital mortality in patients with diabetes (areas under the curve [AUC] for fasting SHR: 0.702; FPG: 0.689) and without diabetes (AUC for fasting SHR: 0.690; FPG: 0.693). The AUC for fasting SHR was not significantly different from that of FPG in diabetic and nondiabetic patients. Moreover, adding fasting SHR or FPG to the original model led to a significant improvement in C-statistic regardless of diabetic status. CONCLUSIONS: This study indicated that, in individuals with AMI, fasting SHR as well as FPG was strongly associated with in-hospital mortality regardless of glucose metabolism status. Fasting SHR and FPG might be considered as a useful marker for risk stratification in this population. TRIAL REGISTRATION: ClinicalTrials.gov NCT01874691.


Asunto(s)
Diabetes Mellitus , Hiperglucemia , Infarto del Miocardio , Humanos , Hemoglobina Glucada , Glucemia/metabolismo , Mortalidad Hospitalaria , Estudios Prospectivos , Diabetes Mellitus/epidemiología , China/epidemiología , Ayuno , Sistema de Registros
8.
Rev Cardiovasc Med ; 24(3): 65, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39077488

RESUMEN

Background: The focus of this investigation into the impact of type 2 diabetes mellitus (T2DM) on left ventricular thrombus (LVT) is (a) the differences in LVT characteristics, (b) long-term clinical outcomes, and (c) differential effects of direct oral anticoagulants (DOAC) among patients with T2DM and without diabetes. Methods: Patients with confirmed LVT from 2009 to 2021 were included. The primary endpoints were major adverse cardiac and cerebrovascular events (MACCE), composite of cardiovascular death, ischemic stroke, and acute myocardial infarction (AMI). The secondary endpoints were all-cause death and cardiovascular death. Multivariable competing-risk regression and cumulative incidence functions (CIF) were used to evaluate the adverse consequences. Results: In total, 1675 patients were assessed initially. Follow-up data were available for 91.1% of the participants. Median follow-up was 3.8 years. This retrospective study ultimately comprised 1068 participants, of which 429 had T2DM. Significantly higher proportions of comorbidities were observed in the T2DM group. The location, morphology, and size of LVT were similar in the two groups. Multivariable analysis suggested a higher risk of MACCE among patients with T2DM. The difference in risk between the two groups after matching and weighting was not statistically significant. Among the whole sample (n = 638) or the just the non-diabetic patients with LVT and anticoagulation (n = 382), the incidence of MACCE did not differ between DOAC treatment and warfarin treatment. In the diabetic LVT population with anticoagulation (n = 256), DOAC treatment was associated with a significantly higher risk of MACCE than was warfarin treatment. Conclusions: The location and morphology of LVT are similar in T2DM and non-diabetic patients. A higher risk of MACCE was found among patients with diabetes.

9.
Rev Cardiovasc Med ; 24(10): 298, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39077565

RESUMEN

Background: Recommendations for drug treatment of left ventricular thrombus (LVT) are based on the ST-segment elevation myocardial infarction (STEMI) guidelines; however, the etiology of LVT has changed. Due to the lack of evidence regarding LVT treatment in the heart failure population, current heart failure guidelines do not cover LVT treatment. We sought to review the etiology of LVT and changes in antithrombotic therapy over the previous 12 years and explore the impact of anticoagulation treatment from a single center's experience. Methods: From January 2009 to June 2021, we studied 1675 patients with a discharge diagnosis of LVT at a single center to investigate the clinical characteristics, incidence of all-cause death, cardiovascular death, ischemic stroke, major adverse cardiac and cerebrovascular events (MACCE), systemic embolism (SE), and major bleeding events. Patients were divided into an anticoagulant group and a non-anticoagulant group according to whether they received oral anticoagulant therapy at discharge. Results: The study included 909 patients (anticoagulation, 510; no anticoagulation, 399). While overall antiplatelet therapy dramatically decreased, more patients with LVT received oral anticoagulation in 2021 (74.0%) than in 2009 (29.6%). In addition, more than half of the patients had heart failure with reduced ejection fraction (HFrEF) each year. The all-cause mortality was 17.3% during 3.8 years of follow-up. The incidences of cardiovascular death, stroke, MACCE, SE, and major bleeding were 16.0%, 3.3%, 19.8%, 5.1%, and 1.7%, respectively. The anticoagulation group had a significantly higher proportion of dilated cardiomyopathy than the non-anticoagulation group (24.7% vs. 5.5%, p < 0.001), and a lower LVEF (34.0 vs. 41.0, p < 0.001). The anticoagulation group also had a higher probability of adverse events on long-term follow-up (p > 0.05). A multivariable competing risk regression model found no significant difference in all six endpoints between the groups (all p > 0.05). Similar results were found by matched and weighted data analysis. Diabetes mellitus (hazard ratio (HR), 1.42; 95% confidence interval (CI), 1.04-1.93; p = 0.027), renal insufficiency (HR, 2.36; 95% CI, 1.60-3.50; p < 0.001), history of previous stroke (HR, 1.60; 95% CI, 1.13-2.29; p = 0.009), and HFrEF (HR, 2.54; 95% CI, 1.78-3.64; p < 0.001) were predictors of increased risk of MACCE. Conclusions: Heart failure, rather than acute myocardial infarction, is currently the primary cause of LVT. A trend towards better prognosis in the no anticoagulation group was noted. Multivariable, matching and weighting analysis showed no improvement in prognosis with anticoagulant therapy. Our study does not negate the efficacy of anticoagulation but suggests the need to strengthen the management of anticoagulation in order to achieve better efficacy.

10.
Mol Ther ; 30(1): 244-255, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34687846

RESUMEN

Cas12a is an RNA-guided endonuclease that has been widely used for convenient multiplex gene editing with low off-target effects. To minimize off-targeting in gene editing, we engineered a variant of LbCas12a (termed Lb-K538R) with more stringent PAM recognition, lower off-targeting capability, and similar editing efficiency in vivo compared with LbCas12a. We also demonstrated that Lb2Cas12a from Lachnospiraceae bacterium MA2020 has extensive gene-editing activities in mammalian cells. Similar to Lb-K538R, the designed Lb2Cas12a variant (termed Lb2-K518R) not only had a more stringent PAM sequence change from YYN to TYN (Y is T or C, N is A, T, C, or G), but also displayed lower off-target effects, thereby enabling more potential target site selections with low off-targeting than the common TTTV (V is A, G, or C) PAM. To determine whether this type of mutation at the homologous position had similar effects in other Cas12a, As-K548R was evaluated. Based on the results of the genome-wide off-target test, As-K548R displayed lower off-target effects. Collectively, our findings indicate that the Cas proteins could be designed to be stringent in PAM recognition to reduce their off-target effects, which suggests a promising and practical approach for minimizing off-targets effects in genome editing.


Asunto(s)
Proteínas Asociadas a CRISPR , Sistemas CRISPR-Cas , Animales , Proteínas Asociadas a CRISPR/genética , Proteínas Asociadas a CRISPR/metabolismo , Endonucleasas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Mamíferos , ARN/genética
11.
Appl Opt ; 62(29): 7721-7729, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37855480

RESUMEN

Due to the huge demand for higher resolution and stable imaging from fluorescent labeling biological systems and life systems, there has been much research and development of structured light illumination imaging (SIM). Despite this, further investigating the possible applications of SIM in other fields is still meaningful. In this paper, super-resolution observation of non-fluorescent samples by a SIM system under reflective illumination is analyzed. The simulation of SIM imaging and image reconstruction is carried out by using an open-source program, and the influences of the structural parameters of the illumination light (fringe direction, phase, and intensity uniformity of the cosine structured light), the optical parameters of the imaging system (selection of the optical transfer function) and the anti-vibration characteristics of the platform on the super-resolution imaging effect are studied. Finally, by optimizing the above influential factors according to simulation results, successful application of SIM in laser processing process monitoring is demonstrated in the experiment. We believe that our research results will provide some reference for the application of SIM in other similar scenarios.

12.
BMC Public Health ; 23(1): 404, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36855085

RESUMEN

OBJECTIVE: To summarise the dynamic characteristics of COVID-19 transmissibility; To analyse and quantify the effect of control measures on controlling the transmissibility of COVID-19; To predict and compare the effectiveness of different control measures. METHODS: We used the basic reproduction number ([Formula: see text]) to measure the transmissibility of COVID-19, the transmissibility of COVID-19 and control measures of 176 countries and regions from January 1, 2020 to May 14, 2022 were included in the study. The dynamic characteristics of COVID-19 transmissibility were summarised through descriptive research and a Dynamic Bayesian Network (DBN) model was constructed to quantify the effect of control measures on controlling the transmissibility of COVID-19. RESULTS: The results show that the spatial transmissibility of COVID-19 is high in Asia, Europe and Africa, the temporal transmissibility of COVID-19 increases with the epidemic of Beta and Omicron strains. Dynamic Bayesian Network (DBN) model shows that the transmissibility of COVID-19 is negatively correlated with control measures. Restricting population mobility has the strongest effect, nucleic acid testing (NAT) has a strong effect, and vaccination has the weakest effect. CONCLUSION: Strict control measures are essential for controlling the COVID-19 outbreak; Restricting population mobility and nucleic acid testing (NAT) have significant impacts on controlling the COVID-19 transmissibility, while vaccination has no significant impact. In light of these findings, future control measures may include the widespread use of new NAT technology and the promotion of booster immunization.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Humanos , Teorema de Bayes , COVID-19/epidemiología , COVID-19/prevención & control , África/epidemiología , Asia
13.
BMC Public Health ; 23(1): 2463, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066518

RESUMEN

BACKGROUND: A major shift in the "dynamic zero-COVID" policy was announced by China's National Health Commission on December 7, 2022, and the subsequent immediate large-scale outbreak of SARS-CoV-2 infections in the entire country has caused worldwide concern. This observational cross-sectional study aimed to describe the epidemiological characteristics of this outbreak in Sichuan, China. METHODS: All data were self-reported online by volunteers. We described the epidemic by characterizing the infection, symptoms, clinical duration, severity, spatiotemporal clustering, and dynamic features of the disease. Prevalence ratio (PR), Odds ratios (ORs) and adjusted ORs were calculated to analyze the associations between risk factors and infection and the associations of risk factors with clinical severity using log-binomial and multivariable logistic regression models; 95% confidence intervals (CIs) and Wald test results were reported. The prevalence rates and clinical severity among different subgroups were compared using the Chi-square and trend Chi-square tests. RESULTS: Between January 6 and 12, 2023, 138,073 volunteers were enrolled in this survey, and 102,645 were infected with COVID-19, holding a prevalence rate of 74.34%; the proportion of asymptomatic infections was 1.58%. Log-binomial regression revealed that the risk of infection increased among those living in urban areas. Multivariable logistic regression analysis showed that female sex, chronic diseases, older age and the fewer doses of vaccine received were associated with an increased risk of severe clinical outcomes after infection. We estimated the mean reproduction number during this pandemic was 1.83. The highest time-dependent reproduction number was 4.15; this number decreased below 1 after 11 days from December 7, 2022. Temporal trends revealed a single peak curve with a plateau pattern of incidence during the outbreak, whereas spatiotemporal clustering analysis showed that the onset in 21 cities in the Sichuan province had four-wave peaks. CONCLUSIONS: The peak of the first wave of Omicron infection in Sichuan Province had passed and could be considered a snapshot of China under the new control strategy. There were significant increases in the risk of severe clinical outcomes after infection among females, with chronic diseases, and the elderly. The vaccines have been effective in reducing poor clinical outcomes.


Asunto(s)
COVID-19 , Anciano , Femenino , Humanos , China/epidemiología , Enfermedad Crónica , COVID-19/epidemiología , Estudios Transversales , Brotes de Enfermedades/prevención & control , SARS-CoV-2 , Encuestas y Cuestionarios , Masculino
15.
Sensors (Basel) ; 23(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36991922

RESUMEN

Adaptive array processing technology for a phased array radar is usually based on the assumption of a stationary environment; however, in real-world scenarios, nonstationary interference and noise deteriorate the performance of the traditional gradient descent algorithm, in which the learning rate of the tap weights is fixed, leading to errors in the beam pattern and a reduced output signal-to-noise ratio (SNR). In this paper, we use the incremental delta-bar-delta (IDBD) algorithm, which has been widely used for system identification problems in nonstationary environments, to control the time-varying learning rates of the tap weights. The designed iteration formula for the learning rate ensures that the tap weights adaptively track the Wiener solution. The results of numerical simulations show that in a nonstationary environment, the traditional gradient descent algorithm with a fixed learning rate has a distorted beam pattern and reduced output SNR; however, the IDBD-based beamforming algorithm, in which a secondary control mechanism is used to adaptively update the learning rates, showed a similar beam pattern and output SNR to a traditional beamformer in a Gaussian white noise background; that is, the main beam and null satisfied the pointing constraints, and the optimal output SNR was obtained. Although the proposed algorithm contains a matrix inversion operation, which has considerable computational complexity, this operation could be replaced by the Levinson-Durbin iteration due to the Toeplitz characteristic of the matrix; therefore, the computational complexity could be decreased to O(n), so additional computing resources are not required. Moreover, according to some intuitive interpretations, the reliability and stability of the algorithm are guaranteed.

16.
Angew Chem Int Ed Engl ; 62(13): e202219084, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36738172

RESUMEN

Ultrathin covalent organic framework (COF) membranes are urgently demanded in molecular/ionic separations. Herein, we reported an electrochemical interfacial polymerization strategy to fabricate ultrathin COF membranes with thickness of 85 nm, by actively manipulate self-healing effect and self-inhibiting effect. The resulting COF membrane exhibited superior performance in brine desalination with the permeation flux of 92 kg m-2 h-1 and the rejection of 99.96 %. Our electrochemical interfacial polymerization strategy enriches the fabrication approach of COF membranes and facilitates the rational design of ultrathin membranes.

17.
Angew Chem Int Ed Engl ; 62(22): e202302355, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-36971597

RESUMEN

We report a covalent organic framework (COF) induced seeding strategy to fabricate metal-organic framework (MOF) membranes. Contrary to graphene oxide nuclei-depositing substrate, COF substrate has uniform pore size, high microporosity and abundant functional groups. We designed a series of charged COF nanosheets to induce the formation of ZIF-8@COF nanosheet seeds with high aspect ratio over 150, which were readily processed into a compact and uniform seed layer. The resulting ZIF-8 membranes with thickness down to 100 nm exhibit an ultrahigh C3 H6 /C3 H8 separation performance and superior long-term stability. Our strategy is also validated by fabricating ultrathin ZIF-67 and UiO-66 membranes.

18.
Angew Chem Int Ed Engl ; 62(42): e202310238, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37665568

RESUMEN

Photosynthesis offers a green approach for the recycling of nicotinamide cofactors primarily NADH in bio-redox reactions. Herein, we report an NADH photosynthesis system where the oxidation of biomass derivatives is designed as an electron supply module (ESM) to afford electrons and superoxide dismutase/catalase (SOD/CAT) cascade catalysis is designed as a reactive oxygen species (ROS) elimination module (REM) to inhibit NADH degradation. Glucose as the electron donor guarantees the reaction sustainability accompanied with oxidative products of gluconic acid and formic acid. Meanwhile, enzyme cascades of SOD/CAT greatly eliminate ROS, leading to a ≈2.00-fold elevation of NADH yield (61.1 % vs. 30.7 %). The initial reaction rate and turnover frequency (TOF) increased by 2.50 times and 2.54 times, respectively, compared with those systems without REM. Our study establishes a novel and efficient platform for NADH photosynthesis coupled to biomass-to-chemical conversion.

19.
J Am Chem Soc ; 144(9): 4168-4177, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35107007

RESUMEN

Enzyme-photocoupled catalytic systems (EPCSs), combining the natural enzyme with a library of semiconductor photocatalysts, may break the constraint of natural evolution, realizing sustainable solar-to-chemical conversion and non-natural reactivity of the enzyme. The overall efficiency of EPCSs strongly relies on the shuttling of energy-carrying molecules, e.g., NAD+/NADH cofactor, between active centers of enzyme and photocatalyst. However, few efforts have been devoted to NAD+/NADH shuttling. Herein, we propose a strategy of constructing a thylakoid membrane-inspired capsule (TMC) with fortified and tunable NAD+/NADH shuttling to boost the enzyme-photocoupled catalytic process. The apparent shuttling number (ASN) of NAD+/NADH for TMC could reach 17.1, ∼8 times as high as that of non-integrated EPCS. Accordingly, our TMC exhibits a turnover frequency (TOF) of 38 000 ± 365 h-1 with a solar-to-chemical efficiency (STC) of 0.69 ± 0.12%, ∼6 times higher than that of non-integrated EPCS.


Asunto(s)
NAD , Semiconductores , Cápsulas , Catálisis , NAD/química
20.
Rev Cardiovasc Med ; 23(10): 329, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39077135

RESUMEN

Background: Transradial artery (TRA) access for percutaneous coronary intervention (PCI) was associated with lower risks of major bleeding and vascular complications compared to transfemoral artery access. Use of large-bore ( ≥ 7-Fr) guiding catheters through TRA approach increased the likelihood of radial artery occlusion (RAO). This study aimed to investigate whether use of the thin-walled 7-Fr Glidesheath Slender, allowing PCI with large-caliber guiding catheters, is superior to standard 7-Fr Cordis sheath with respect to periprocedural RAO within 24 hours after transradial coronary intervention (TRI) in complex lesions. Methods: A prospective randomized, controlled, single-blinded (patient-blinded) trial was conducted, randomizing 504 patients with TRI for complex lesions to either 7-Fr Glidesheath Slender or conventional 7-Fr Cordis sheath. The primary outcome was defined as the incidence of periprocedural RAO with Doppler ultrasound during the first 24 hours after TRI. Results: The incidence of early RAO was 10.3% for 7-Fr Glidesheath Slender and 13.5% for conventional 7-Fr sheath (p = 0.271). The procedural success rate for Glidesheath Slender was 92.9% and for Cordis sheath was 93.7% (p = 0.722). There was no signficiant difference between treatment arms in terms of local hematoma and radial spasm, whereas use of the Glidesheath Slender was associated with significantly less pain during the procedure (numeric rating scale [NRS], 2.27 ± 0.75 vs. 2.45 ± 0.95, p = 0.017). The assessment of radial artery in ultrasound parameters after complex TRI was improved with Glidesheath Slender. Conclusions: Among patients with complex coronary lesions undergoing TRI, 7-Fr Glidesheath Slender was not superior to conventional 7-Fr in the prevention of periprocedural RAO within 24 hours following complex PCI, without reducing RAO occurrence. Clinical Trial Registration: NCT04748068.

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