Polar alcohol guest molecules regulate the stacking modes of 2-D MOF nanosheets.

The modulation of two-dimensional metal-organic framework (2-D MOF) nanosheet stacking is an effective means to improve the properties and promote the application of nanosheets in various fields. Here, we employed a series of alcohol guest molecules (MeOH, EtOH and PrOH) to modulate Zr-BTB (BTB = benzene-1,3,5-tribenzoate) nanosheets and to generate untwisted stacking. The distribution of stacking angles was statistically analyzed from high-angle annular dark-field (HAADF) and fast Fourier transform (FFT) images. The ratios of untwisted stacking were calculated, such as 77.01% untwisted stacking for MeOH, 83.45% for EtOH, and 85.61% for PrOH. The obtained untwisted Zr-BTB showed good separation abilities for different substituted benzene isomers, superior para selectivity and excellent column stability and reusability. Control experiments of 2-D Zr-TCA (TCA = 4,4',4''-tricarboxytriphenylamine) and Zr-TATB (TATB = 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tribenzoic acid) nanosheets with similar pore sizes and stronger polarity regulated by the alcohol guests exhibited moderate separation performance. The electron microscopy images revealed that polar alcohol regulation dominantly generated the twisted stacking of Zr-TCA and Zr-TATB with various Moiré patterns. Polar guest molecules, such as alcohols, provide strong host-guest interactions during the regulation of MOF nanosheet stacking, providing an opportunity to design new porous Moiré materials with application prospects.

Increasing Mass Transfer Resistance of MOFs as a Reverse Tuning Strategy to Achieve High-Resolution Gas Chromatographic Separation.

In separation science, precise control and regulation of the MOF stationary phase are crucial for achieving a high separation performance. We supposed that increasing the mass transfer resistance of MOFs with excessive porosity to achieve a moderate mass transfer resistance of the analytes is the key to conducting the MOF stationary phase with a high resolution. Three-dimensional UiO-67 (UiO-67-3D) and two-dimensional UiO-67 (UiO-67-2D) were chosen to validate this strategy. Compared with UiO-67-3D with overfast mass transfer and low retention, the reduced porosity of UiO-67-2D increased the mass transfer resistance of analytes in reverse, resulting in improved separation performance. Kinetic diffusion experiments were conducted to verify the difference in mass transfer resistance of the analytes between UiO-67-3D and UiO-67-2D. In addition, the optimization of the UiO-67-2D thickness for separation revealed that a moderate diffusion length of the analytes is more advantageous in achieving the equilibrium of absorption and desorption.

Bipolar Molecular Torque Wrench Modulates the Stacking of Two-Dimensional Metal-Organic Framework Nanosheets.

The precise modulation of nanosheet stacking modes introduces unforeseen properties and creates momentous applications but remains a challenge. Herein, we proposed a strategy using bipolar molecules as torque wrenches to control the stacking modes of 2-D Zr-1,3,5-(4-carboxylphenyl)-benzene metal-organic framework (2-D Zr-BTB MOF) nanosheets. The bipolar phenyl-alkanes, phenylmethane (P-C1) and phenyl ethane (P-C2), predominantly instigated the rotational stacking of Zr-BTB-P-C1 and Zr-BTB-P-C2, displaying a wide angular distribution. This included Zr-BTB-P-C1 orientations at 0, 12, 18, and 24° and Zr-BTB-P-C2 orientations at 0, 6, 12, 15, 24, and 30°. With reduced polarity, phenyl propane (P-C3) and phenyl pentane (P-C5) introduced steric hindrance and facilitated alkyl hydrophobic interactions with the nanosheets, primarily resulting in the modulation of eclipsed stacking for Zr-BTB-P-C3 (64.8%) and Zr-BTB-P-C5 (93.3%) nanosheets. The precise angle distributions of four Zr-BTB-P species were in agreement with theoretical calculations. The alkyl induction mechanism was confirmed by the sequential guest replacement and 2-D 13C-1H heteronuclear correlation (HETCOR). In addition, at the single-particle level, we first observed that rotational stacked pores exhibited similar desorption rates for xylene isomers, while eclipsed stacked pores showed significant discrepancy for xylenes. Moreover, the eclipsed nanosheets as stationary phases exhibited high resolution, selectivity, repeatability, and durability for isomer separation. The universality was proven by another series of bipolar acetate-alkanes. This bipolar molecular torque wrench strategy provides an opportunity to precisely control the stacking modes of porous nanosheets.

[Rational design of high performance metal organic framework stationary phase for gas chromatography].

Metal organic frameworks (MOFs) are assembled from metal ions or clusters and organic ligands. The high tunability of these components offers a solid structural foundation for achieving efficient gas chromatography (GC) separation. This review demonstrates that the design of high performance MOFs with suitable stationarity should consider both the thermodynamic interactions provided by these MOFs and the kinetic diffusion of analytes. Thermodynamic parameters are basic indicators for describing the interactions between various analytes and the stationary phase. Thermodynamic parameters such as retention factors, McReynolds constants, enthalpy changes, and entropy changes can reflect the relative intensity of thermodynamic interactions. For example, a larger enthalpy change indicates a stronger thermodynamic interaction between the analytes and stationary phase, whereas a smaller enthalpy change indicates a weaker interaction. In addition, the degree of entropy change reflects the relative degrees of freedom of analytes in the stationary phase. A larger entropy change indicates that the analytes have fewer degrees of freedom in the stationary phase. The higher the degree of restriction, the closer the adsorption of the analytes and, thus, the longer the retention time. Thermodynamic interactions, such as metal affinity, π-π interactions, polarity, and chiral sites, can be rationally introduced into MOF structures by pre- or post-modifications depending on the target analytes. These tailored thermodynamic interactions create a favorable environment with subtle differences for efficient analyte separation. For example, MOF stationarity may require large conjugation centers to provide specific π-π interactions to separate benzenes. Chiral groups may be required in the MOF structure to provide sufficient interactions to separate chiral isomers. The kinetic diffusion rate of the analytes is another critical factor that affects the separation performance of MOFs. The diffusion coefficients of analytes in the stationary phase (Ds) can be used to evaluate their diffusion rates. The chromatographic dynamics equation illustrates that the chromatographic peak of analytes tends to be sharper and more symmetrical when the Ds is large, whereas a wider trailing peak may appear when the Ds is small. The Van Deemter equation also proves that a low Ds may lead to a high theoretical plate height and low column efficiency, whereas a high Ds may lead to a low theoretical plate height and increased column efficiency. Analyte diffusion can be significantly influenced by the pore size, shape, particle size, and packing mode of MOFs. For instance, an excessively small pore size results in increased mass transfer resistance, which affects the diffusion of analytes in the stationary phase, probably leading to serious peak trailing. Thus, a suitable pore size is required to enhance the kinetic diffusion of analytes and improve the separation performance of MOFs. Theoretically, the design of a high performance MOF stationary phase requires the creation of routes for the rapid diffusion of analytes. However, the separation ability of an MOF is determined by not only the kinetic diffusion rate of the analytes but also the thermodynamic interactions it provides. An excessively fast diffusion rate may lead to insufficient interactions between the analytes and MOFs, compromising their ability to effectively separate different analytes. The thermodynamic interactions and kinetic diffusion of analytes are synergistic and mutually essential. Therefore, this review concludes with research on the influence of both the thermodynamic interactions and kinetic diffusion of analytes on the performance of MOF stationary phases. Based on the findings of this review, we propose that high performance MOF stationary phases can be achieved by balancing the thermodynamic interactions and kinetic diffusion of analytes in these phases through the rational design of the MOF structure. We believe that this review provides useful guidelines for the design of high performance MOF stationary phases.

Association of exposures to serum terpenes with the prevalence of dyslipidemia: a population-based analysis.

This study sought to examine hitherto unresearched relationships between serum terpenes and the prevalence of dyslipidemia. Serum terpenes such as limonene, α-pinene, and ß-pinene from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) were used as independent variables in this cross-sectional study. Continuous lipid variables included total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), residual cholesterol (RC), and apolipoprotein B (Apo B). Binary lipid variables (elevated TC, ≥5.18 mmol/L; lowered HDL-C, <1.04 mmol/L in men, and <1.30 mmol/L in women; elevated non-HDL-C, ≥4.2 mmol/L; elevated TG, ≥1.7 mmol/L; elevated LDL-C, ≥3.37 mmol/L; elevated RC, ≥1.0 mmol/L; and elevated Apo B, ≥1.3 g/L) suggest dyslipidemia. The relationships between the mixture of serum terpenes with lipid variables were investigated using weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR). The study for TC, HDL-C, and non-HDL-C included a total of 1,528 people, whereas the analysis for TG, LDL-C, RC, and Apo B comprised 714 participants. The mean age of the overall participants was 47.69 years, and 48.77% were male. We found that tertiles of serum terpene were positively associated with binary (elevated TC, non-HDL-C, TG, LDL-C, RC, Apo B, and lowered HDL-C) and continuous (TC, non-HDL-C, TG, LDL-C, RC, and Apo B, but not HDL-C) serum lipid variables. WQS regression and BKMR analysis revealed that the mixture of serum terpenes was linked with the prevalence of dyslipidemia. According to our data, the prevalence of dyslipidemia was correlated with serum concentrations of three terpenes both separately and collectively.

Anisotropic flexibility and rigidification in a TPE-based Zr-MOFs with scu topology.

Tetraphenylethylene (TPE)-based ligands are appealing for constructing metal-organic frameworks (MOFs) with new functions and responsiveness. Here, we report a non-interpenetrated TPE-based scu Zr-MOF with anisotropic flexibility, that is, Zr-TCPE (H4TCPE = 1,1,2,2-tetra(4-carboxylphenyl)ethylene), remaining two anisotropic pockets. The framework flexibility is further anisotropically rigidified by installing linkers individually at specific pockets. By individually installing dicarboxylic acid L1 or L2 at pocket A or B, the framework flexibility along the b-axis or c-axis is rigidified, and the intermolecular or intramolecular motions of organic ligands are restricted, respectively. Synergistically, with dual linker installation, the flexibility is completely rigidified with the restriction of ligand motion, resulting in MOFs with enhanced stability and improved separation ability. Furthermore, in situ observation of the flipping of the phenyl ring and its rigidification process is made by 2H solid-state NMR. The anisotropic rigidification of flexibility in scu Zr-MOFs guides the directional control of ligand motion for designing stimuli-responsive emitting or efficient separation materials.

Remote cardiac rehabilitation program during the COVID-19 pandemic for patients with stable coronary artery disease after percutaneous coronary intervention: a prospective cohort study.

OBJECTIVE: The coronavirus disease-19 (COVID-19) pandemic restricts rapid implementation of in-person delivery of cardiac rehabilitation (CR) at the center for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI), thus enabling a cohort comparison of in-person vs. remote CR program. This study aims to investigate outcomes of exercise capacity, health-related quality of life (HRQL), mental health, and family burden of stable CAD patients undergoing PCI in low-to-moderate risk after different delivery models of CR program. METHODS: The study included a cohort of stable CAD patients undergoing PCI who had experienced two naturally occurring modes of CR program after hospital discharge at two time periods, January 2019 to December 2019 (in-person CR program) and May 2020 to May 2021 (remote CR program). The exercise capacity was assessed by means of 6-min walk test (6MWT), maximal oxygen uptake (VO2max) and the respiratory anaerobic threshold (VO2AT) before discharge, at the end of the 8-week and 12-week in-person or remote CR program after discharge. RESULTS: No adverse events occurred during the CR period. CAD patients had a longer distance walked in 6 min with a higher VO2max after 8-week and 12-week CR program whether in-person or remote model (p < 0.05). The distance walked in 6 min was longer and the maximal oxygen uptake (VO2max) was higher at the end of the 12-week in-person or remote CR program than 8-week in-person or remote CR program (p < 0.05). The respiratory anaerobic threshold (VO2AT) of CAD patients was decreased after 8-week CR program whether in-person or remote model (p < 0.05). CAD patients receiving remote CR program exhibited higher HRQL scores in domains of vitality (p = 0.048), role emotional (p = 0.039), mental health (p = 0.014), and the summary score of the mental composite (p = 0.048) compared to in-person CR program after 8 weeks. The anxiety and depression scores of CAD patients undergoing PCI were decreased after 8-week CR program whether in-person or remote model (p < 0.05). The CAD patients receiving remote delivery showed lower anxiety and depression scores compared to those receiving in-person delivery at the end of the 8-week CR program (p < 0.05). It was found that the family burden scores of CAD patients undergoing PCI were reduced after 8-week and 12-week CR program whether in-person or remote model (p < 0.05). The CAD patients receiving remote CR program showed lower family burden scores than those receiving in-person CR program after whether 8 weeks or 12 weeks (p < 0.05). CONCLUSION: These data indicate that a properly designed and monitored remote delivery represents a feasible and safe model for low-to-moderate-risk, stable CAD patients undergoing PCI inaccessible to in-person CR during the COVID-19 pandemic.

Effect of mindfulness-based stress reduction in patients with acute myocardial infarction after successful primary percutaneous coronary intervention: a retrospective study.

OBJECTIVE: This study aimed to examine the effects of mindfulness-based stress reduction (MBSR) in patients with acute myocardial infarction (AMI) after primary percutaneous coronary intervention (PPCI). METHODS: A retrospective study was conducted with data collected from AMI patients who underwent successful PPCI. The study included 61 cases that received 8-week MBSR intervention (MBSR group) and 61 cases that received weekly health education (control group) over the same period. Outcome measures, including hemodynamic parameters, psychosocial characteristics [Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS), Perceived Social Support Scale (PSSS)], health-related quality of life [HRQoL, 7-item Seattle Angina Questionnaire (SAQ-7)], and major adverse cardiovascular events (MACE), were assessed at baseline (T1), post-intervention (T2), 1 month after the post-intervention (T3) and 3 months after the post-intervention (T4). RESULTS: Compared to the control group, the MBSR group showed improvements in blood pressure, specifically in systolic blood pressure (SBP) at T4, and diastolic blood pressure (DBP) at T3 and T4, and mean arterial blood pressure (MABP) at T3 and T4. Additionally, the MBSR group had lower scores of anxiety and perceived stress (HADS, PSS) and higher scores of perceived social support (PSSS) after the intervention. Furthermore, the MBSR group had higher scores on the SAQ-7 at all measurement points. The control group had a significantly higher total MACE rate compared to the MBSR group (26.23% vs. 9.84%). CONCLUSIONS: This study provides support for the potential benefits of MBSR as an adjunctive treatment for AMI patients undergoing PPCI.

Gradual deterioration of fatty liver disease to liver cancer via inhibition of AMPK signaling pathways involved in energy-dependent disorders, cellular aging, and chronic inflammation.

Introduction: Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer kind. According to recent research, a fatty liver increases the risk of hepatocellular cancer. Nevertheless, the AMPK signaling pathway is crucial. In addition, 5'-AMP-activated protein kinase (AMPK) is strongly linked to alterations in the tumor microenvironment, such as inflammation, hypoxia, and aging. The objective of this study is to evaluate the impact of the AMPK signaling pathway on the progression of fatty liver to HCC. Methods: In this study, we established a mouse liver cancer model using high-fat diets and nano-nitrosamines (nano-DEN). In addition, we employed a transcriptomic technique to identify all mRNAs detected in liver samples at the 25th weekexpression of proteins linked with the LKB1-AMPK-mTOR signaling pathway, inflammation, aging, and hypoxia was studied in microarrays of liver cancer tissues from mice and humans. These proteins included p-AMPK, LKB1, mTOR, COX-2, ß-catenin, HMGB1, p16, and HIF-1α. Results: Data were collected at different times in the liver as well as in cancerous and paracancerous regions and analyzed by a multispectral imaging system. The results showed that most of the genes in the AMPK signaling pathway were downregulated. Prakk1 expression was upregulated compared to control group but downregulated in the cancerous regions compared to the paracancerous regions. Stk11 expression was downregulated in the cancerous regions. Mtor expression was upregulated in the cancerous regions. During liver cancer formation, deletion of LKB1 in the LKB1-AMPK-mTOR signaling pathway reduces phosphorylation of AMPK. It contributed to the upregulation of mTOR, which further led to the upregulation of HIF1α. In addition, the expression of ß-catenin, COX-2, and HMGB1 were upregulated, as well as the expression of p16 was downregulated. Discussion: These findings suggest that changes in the AMPK signaling pathway exacerbate the deterioration of disrupted energy metabolism, chronic inflammation, hypoxia, and cellular aging in the tumor microenvironment, promoting the development of fatty liver into liver cancer.

Newly revealed variants of SERPINA3 in generalized pustular psoriasis attenuate inhibition of ACT on cathepsin G.

Generalized pustular psoriasis (GPP) is an autoinflammatory skin disease whose pathogenesis has not yet been fully elucidated. Alpha-1-antichymotrypsin(ACT) is a protein encoded by the SERPINA3 gene and an inhibitor of cathepsin G. One study of a European sample suggested that the loss of ACT function caused by SERPINA3 mutation is implicated in GPP. However, the role of SERPINA3 in the pathogenesis of GPP in other ethnic populations is unclear. To explore this, seventy children with GPP were performed next-generation sequencing to identify rare variants in the SERPINA3 gene. Bioinformatic analysis and functional tests were used to determine the effects of the variants, and a comprehensive analysis was performed to determine the pathogenicity of the variants and whether they are associated with GPP. One rare deletion and three rare missense variants were identified in the SERPINA3 gene in GPP. The deletion variant c.1246_1247del was found to result in a mutant protein with an extension of 10 amino acids and a C-terminal of 20 amino acids that was completely different from the wild-type. This mutant was found to impede secretion of ACT, thus failing to function as an inhibitor of cathepsin G. Two missense variants were found to reduce the ability of ACT to inhibit cathepsin G enzymatic activity. The association analysis suggested that the deletion variant is associated with GPP. This study identified four rare novel mutations of SERPINA3 and demonstrated that three of these mutations result in loss of function, contributing to the pathogenesis of pediatric-onset GPP in the Asian population.

Development and Validation of a Nomogram for Predicting Radial Artery Spasm During Coronary Angiography.

This study describes an attempt to develop a user-friendly nomogram incorporating psychological factors to individually predict the risk of radial artery spasm. Patients consecutively recruited between June 2020 and June 2021 constituted the development cohort for retrospective analysis of the development of a prediction model. Least absolute shrinkage and selection operator regression combined with clinical significance was employed to screen out appropriate independent variables. The model's discrimination and calibration were subsequently evaluated and calibrated by using the C-index, receiver operating characteristic (ROC) curve, and calibration plot. Decision curve analysis was also performed to evaluate the net benefit with the nomogram, and internal validation was assessed using bootstrapping validation. The predictors included in the risk nomogram included "body mass index ," "anxiety score," "duration of interventional surgery," "latency time (time spent waiting in the catheterization laboratory)," "vascular circuity (substantial changes in the curvature of vessels)," and "puncture number." The derived model showed good discrimination with an area under the ROC curve of .77, a C-index of .771 (95% CI: .72-.822) and good calibration. Decision curve analysis indicated that the nomogram provided a better net benefit than the alternatives.

Enhancing Separation Abilities of "Low-Performance" Metal-Organic Framework Stationary Phases through Size Control.

Peak broadening and peak tailing are common but rebarbative phenomena that always occur when using metal-organic frameworks (MOFs) as stationary phases. These phenomena result in diverse "low-performance" MOF stationary phases. Here, by adjusting the particle size of MOF stationary phases from microscale to nanoscale, we successfully enhance the separation abilities of these "low-performance" MOFs. Three zirconium-based MOFs (NU-1000, PCN-608, and PCN-222) with different organic ligands were synthesized with sizes of tens of micrometers and hundreds of nanometers, respectively. All the nanoscale MOFs exhibited exceedingly higher separation abilities than the respective microscale MOFs. The mechanism investigation proved that reducing the particle size can reduce the mass transfer resistance, thus enhancing the column efficiency by controlling the separation kinetics. Modulating the particle size of MOFs is an efficient way to enhance the separation capability of "low-performance" MOFs and to design high-performance MOF stationary phases.

A clinical trial for computed tomography myocardial perfusion based non-invasive index of microcirculatory resistance (MPBIMR): rationale and trial design.

INTRODUCTION: Accurate and rapid assessment of the coronary microcirculation has become an important medical challenge. However, reliable and non-invasive quantitative methods to diagnose coronary microvascular disease (CMVD), select treatments for coronary artery disease (CAD), and therefore improve coronary microcirculation are lacking. Current detection methods have limitations. Therefore, we will assess whether a new detection method, the non-invasive index of microcirculatory resistance (IMR), based on computed tomography (CT) perfusion and hydrodynamics (CT-IMR), can effectively evaluate the function of coronary microvessels. METHODS: We will conduct a multicenter, randomized, open-label study, including a Phase I single-center and Phase II multicenter trial, to assess the accuracy of the non-invasive CT-IMR coronary measurement of microcirculation function. The study will enroll 295 patients who will undergo coronary CT angiography (CCTA), dynamic CT-myocardial perfusion imaging (CT-MPI), invasive coronary angiography (ICA), and invasive IMR. This study will identify the key influencing factors when calculating myocardial microcirculation perfusion and develop an accurate three-dimensional coronary reconstruction method and a non-invasive coronary IMR calculation method based on computational fluid dynamics (CFD). This will facilitate the development of a non-invasive system to detect and measure coronary microcirculation. CONCLUSION: The clinical trial for computed tomography myocardial perfusion based non-invasive index of microcirculatory resistance (MPBIMR) will establish the key influencing factors when calculating myocardial microcirculation perfusion and create a non-invasive CT-IMR calculation method based on CFD. This method may diagnose patients with simple coronary microvascular lesions and those with coronary microvascular lesions combined with coronary vascular lesions.

Linker Scissoring Strategy Enables Precise Shaping of Metal-Organic Frameworks for Chromatographic Separation.

Precise shaping of metal-organic frameworks (MOFs) is significant in both fundamental coordination chemistry and practical applications, such as catalysis, separation, and biomedicine. Herein, we demonstrated a linker scissoring strategy for precisely shaping MOFs through surface conformational pairing. In this strategy, the bidentate linkers which were designed according to the original tetratopic ligands and the coordination environment of MOF surfaces, were utilized as the covering agents. The shape of these covering agents and the surface conformation of metals onto MOFs restricted them to coordinate on specific MOF facets thus precisely controlling the shape of the MOFs. Different shapes of PCN-608 from nanoplate (PCN-NP) to nanorod (PCN-NR) have been targeted by adding different bidentate linkers. The universality of this strategy was demonstrated by controlling the shapes of the NU-MOFs from nanoplate to nanorod. This strategy provides a new guiding principle to synthesize MOF nanocrystals with controlled shapes.

Homogeneously Mixing Different Metal-Organic Framework Structures in Single Nanocrystals through Forming Solid Solutions.

Pore engineering plays a significant role in the applications of porous materials, especially in the area of separation and catalysis. Here, we demonstrated a metal-organic framework (MOF) solid solution (MOSS) strategy to homogeneously and controllably mix NU-1000 and NU-901 structures inside single MOF nanocrystals. The key for the homogeneous mixing and forming of MOSS was the bidentate modulator, which was designed to have a slightly longer distance between two carboxylate groups than the original tetratopic ligand. All of the MOSS nanocrystals showed a uniform pore size distribution with a well-tuned ratio of mesopores to micropores. Because of the appropriate pore ratio, MOSS nanocrystals can balance the thermodynamic interactions and kinetic diffusion of the substrates, thus showing exceedingly higher separation abilities and a unique elution sequence. Our work proposes a rational strategy to design mixed-porous MOFs with controlled pore ratios and provides a new direction to design homogeneously mixed MOFs with a high separation ability and unique separation selectivity.

Precise Spatial-Designed Metal-Organic-Framework Nanosheets for Efficient Energy Transfer and Photocatalysis.

High-efficiency photocatalysis in metal-organic frameworks (MOF) and MOF nanosheets (NSs) are often limited by their short-lived charge separation as well as self-quenching. Here, we propose to use the energy-transfer process (EnT) to increase charge separation, thus enhancing the catalytic performance of a series of MOF NSs. With the use of NS, the photocatalyst can also be well isolated to reduce self-quenching. Tetrakis(4-carboxyphenyl) porphyrin (H4 TCPP) and 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4 TBAPy) linkers were chosen as the acceptor and donor moieties, respectively. Accounting for the precise spatial design afforded by the MOF NSs, the donor and acceptor moieties could be closely positioned on the NSs, allowing for an efficient EnT process as well as a high degree of site isolation. Two templates, donor-on-acceptor NS and acceptor-on-donor NS catalysts, were successfully synthesized, and the results show that the second one has much enhanced catalytic performances over the first one due to site-isolated active photocatalysts.

[Application of gas chromatography separation based on metal-organic framework material as stationary phase].

Metal-organic frameworks (MOFs) are a new class of porous materials, which are synthesized using organic ligands and inorganic metal ions or metal clusters. MOFs possess tunable structures through the self-assembly of a large number of organic linkers and metal nodes, which is beyond the scope of conventional porous materials. In addition, MOFs have excellent properties, including the lowest density (as low as 0.13 g/cm), highest specific surface area (as high as 10400 m2/g), and largest pore aperture (as large as 9.8 nm) among all porous materials reported till date. Because of their high porosity, large surface area, tunable apertures, as well as high chemical and thermal stabilities, MOFs have been widely applied in the fields of adsorption, separation, and catalysis. In addition, MOFs have been successfully applied as stationary phases for isomer separation in gas chromatography (GC). Since the use of the first MOF (MOF-508) packed column for the separation of alkane isomers in GC, several other MOFs (e. g., MIL-47, MOF-5, and ZIF-8) have been employed for the GC separation of isomers. However, packed-column-type separation not only requires gram-scale quantities of MOFs, thereby increasing the analysis cost, but also results in poor separation efficiency. The first MOF (MIL-101) capillary column designed toward cost reduction allowed for the baseline separation of xylene and ethylbenzene isomers within 100 s under constant-temperature conditions. Since then, the capillary-type column has been widely utilized in the MOF-based stationary phase for GC separation.Alkanes, xylene isomers and ethyl toluene, oxy-organics and organic pollutants are not only important chemicals in industry but also harmful environmental pollutants. Thus, the separation of these analytes is of practical importance environmental monitoring and industrial quality control. However, it is difficult to realize the efficient separation and detection of these isomers or racemates because of their similar boiling points and molecular sizes. In the past decades, GC was utilized as a rapid and efficient technique for the separation of the abovementioned analytes. The stationary phase used in GC plays a dominant role in the separation processes. This review summarizes the MOF-based GC separation of the abovementioned targets based on the different classification of analytes, including alkanes, xylenes, racemates, oxy-organics and persistent organic pollutants.The separation mechanisms of different analytes are also discussed according to the structural benefits of MOFs. The separation mechanisms mainly involve van der Waals forces between the MOFs and analytes, interactions between the unsaturated metal sites and different functional groups of the analytes, molecular sieve effect or shape selectivity, and hydrogen-bond or π-π interactions. In addition, the chiral recognition abilities of MOFs possibly depend on the interactions between the chiral active sites in chiral MOFs and racemates.Furthermore, efficient GC separation is influenced by thermodynamic and kinetic factors. The thermodynamic factor is mainly the difference between the partition coefficients of the separated components, which also reflects the properties of the analytes as well as the interactions between the stationary phase and the analytes. The kinetic factor also affects the column efficiency and chromatographic peak shape. Compared with traditional inorganic porous materials, MOFs with tunable structures are more favorable for optimizing the separation of isomers from both thermodynamic and kinetic standpoints. Therefore, this review summarizes the separation mechanism when using MOFs as stationary phases for isomer separation via thermodynamic and kinetic analyses. We hope the review would aid the state-of-art design of MOF stationary phases for high efficient isomer separations in GC.

The c.863A>G (p.Glu288Gly) variant of the CTSD gene is not associated with CLN10 disease.

BACKGROUND: Cathepsin D is a lysosomal aspartic protease encoded by the CTSD gene. It plays important roles in many biological processes. Biallelic loss-of-function mutation of CTSD is considered a cause of CLN10 disease. CLN10 is a rare autosomal recessive disorder that is one of 14 types of neuronal ceroid lipofuscinoses (NCLs). To date, only a few cases of CLN10 and 12 disease-causing mutations have been reported worldwide. METHODS: Exome sequencing was performed on a 15-year-old girl with pervasive brain developmental disorder. The effects of the identified variants were investigated through multiple functional experiments. RESULTS: There were no differences in mRNA and protein expression, intracellular localization, maturation, and proteolytic activity between the cells with the mutant CTSD gene and those with the wild-type CTSD gene. CONCLUSION: These results suggest that the c.863A>G (p.Glu288Gly) homozygous variant is not a pathogenic variation, but a benign variant.

Modulating the stacking modes of nanosized metal-organic frameworks by morphology engineering for isomer separation.

Modulating different stacking modes of nanoscale metal-organic frameworks (MOFs) introduces different properties and functionalities but remains a great challenge. Here, we describe a morphology engineering method to modulate the stacking modes of nanoscale NU-901. The nanoscale NU-901 is stacked through solvent removal after one-pot solvothermal synthesis, in which different morphologies from nanosheets (NS) to interpenetrated nanosheets (I-NS) and nanoparticles (NP) were obtained successfully. The stacked NU-901-NS, NU-901-I-NS, and NU-901-NP exhibited relatively aligned stacking, random stacking, and close packing, respectively. The three stacked nanoscale NU-901 exhibited different separation abilities and all showed better performance than bulk phase NU-901. Our work provides a new morphology engineering route for the modulation of the stacking modes of nano-sized MOFs and improves the separation abilities of MOFs.

Enhancing the enzymatic inhibition performance of Cu-based metal-organic frameworks by shortening the organic ligands.

Creating more exposed active sites on the metal-organic framework (MOF) surface is crucial for enhancing the recognition ability of MOF artificial receptors. Here, a copper-based MOF Cu(im)2 (im = imidazole) was utilized to act as an artificial receptor, inhibiting the activity of α-chymotrypsin. The shortest diazole ligand reduced the distance between regenerative copper sites, creating as many active sites as possible on the MOF unit surface. The amount of copper(ii) centers on the Cu(im)2 surface was calculated to be 4.96 × 106µm-2. Thus, Cu(im)2 showed exceedingly higher inhibition performance than other copper-based MOFs. The ChT activity was almost inhibited (88.8%) after the incubation with only 20 µg mL-1 Cu(im)2 for 10 min. The binding between ChT and Cu(im)2 was very fast with high affinity. Further results proved that Cu(im)2 inhibited the activity of ChT through electrostatic interactions and coordination interactions via the mixed inhibition mode. This strategy to use short ligands to create more active sites on the MOF surface provides a new direction to enhance the inhibition efficiency.