Nanoscale metal–organic frameworks (NMOFs) have proven to be a class of promising drug carriers as a result of their high porosity, crystalline nature with definite structure information, and ...potential for further functionality. However, MOF‐based drug carriers with active tumor‐targeting function have not been extensively researched until now. Here we show a strategy for constructing active tumor‐targeted NMOF drug carriers by anchoring functional folic acid (FA) molecules onto the metal clusters of NMOFs. Two zirconium‐based MOFs, MOF‐808 and NH2‐UiO‐66, were chosen as models to reduce to the nanoscale for application as drug carriers, and then the terminal carboxylates of FA molecules were coordinated to Zr6 clusters on the surfaces of the nanoparticles by substitution of the original formate or terminal ‐OH ligands. The successful modification with FA was confirmed by solid‐state 13C MAS NMR and UV/Vis spectroscopy and other characterization methods. Drug loading and controlled release behavior at different pH were determined by utilizing the anticancer drug 5‐fluorouracil (5‐FU) as the model drug. Confocal laser scanning microscopy measurements further demonstrated that 5‐FU‐loaded FA‐NMOFs have excellent targeting ability through the efficient cellular uptake of FA‐NMOFs. This work opens up a new avenue to the construction of active tumor‐targeted NMOF‐based drug carriers with potential for cancer therapies.
Targeted drug delivery: Nanoscale metal–organic frameworks modified with folic acid (FA‐NMOFs) have been prepared as potential drug carriers for targeted delivery to tumor cells (see figure). The anticancer drug 5‐fluorouracil (5‐FU) was encapsulated in the pores of the FA‐NMOFs. The 5‐FU‐loaded FA‐NMOFs showed excellent biocompatibility and were found to effectively kill tumor cells through the targeting effect of the FA‐NMOFs.
Covalent‐organic frameworks (COFs) have been recognized as a new type of promising photocatalysts for hydrogen evolution. To investigate how different functional groups attached in the backbone of ...COFs affect the overall photocatalytic H2 evolution, for the first time, we selected and synthesized a series of ketoenamine‐based COFs with the same host framework as model system. It includes TpPa−COF−X (X=−H, −(CH3)2, and −NO2) with three different groups attached in the backbone of TpPa−COF. We systematically investigated the differences in morphology, light‐absorption intensity and band gap of these 2D COFs. The results of photocatalytic H2 evolution measurements indicate that the TpPa−COF−(CH3)2 shows the best activity, while the activity of TpPa−COF−NO2 is relatively low compared to that of other two COFs in the system. Moreover, the separation ability of photogenerated charge was also followed the order of TpPa−COF−(CH3)2>TpPa−COF>TpPa−COF−NO2. The best photocatalytic H2 production performance of TpPa−COF−(CH3)2 in these systems should be mainly attributed to the better electron‐donating ability of −CH3 groups compared to −H or −NO2 group, which result in more efficient charge transferring in the inner of the material. This work demonstrates that reasonably adding electron‐donating group in TpPa−COFs can lead to a better photocatalytic H2 evolution activity, and which is meaningful for further design of efficient COF‐based photocatalysts for H2 evolution.
Photocatalysis: A series ketoenamine‐based COFs of TpPa−COF−X (X=−H, −(CH3)2, and −NO2) exhibit significant difference on the visible light absorbance and efficiency of photocatalytic H2 evolution, which can be attributed to strengthen charge carrier mobilities both in‐plane and in the stacking direction because of the electron‐donating groups.
Thyroid dysfunction is associated with cardiovascular diseases. However, the role of thyroid function in lipid metabolism remains partly unknown. The present study aimed to investigate the causal ...association between thyroid function and serum lipid metabolism via a genetic analysis termed Mendelian randomization (MR).
The MR approach uses a genetic variant as the instrumental variable in epidemiological studies to mimic a randomized controlled trial. A two-sample MR was performed to assess the causal association, using summary statistics from the Atrial Fibrillation Genetics Consortium (n = 537,409) and the Global Lipids Genetics Consortium (n = 188,577). The clinical measures of thyroid function include thyrotropin (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) levels, FT3:FT4 ratio and concentration of thyroid peroxidase antibodies (TPOAb). The serum lipid metabolism traits include total cholesterol (TC) and triglycerides, high-density lipoprotein, and low-density lipoprotein (LDL) levels. The MR estimate and MR inverse variance-weighted method were used to assess the association between thyroid function and serum lipid metabolism.
The results demonstrated that increased TSH levels were significantly associated with higher TC (β = 0.052, P = 0.002) and LDL (β = 0.041, P = 0.018) levels. In addition, the FT3:FT4 ratio was significantly associated with TC (β = 0.240, P = 0.033) and LDL (β = 0.025, P = 0.027) levels. However, no significant differences were observed between genetically predicted FT4 and TPOAb and serum lipids.
Taken together, the results of the present study suggest an association between thyroid function and serum lipid metabolism, highlighting the importance of the pituitary-thyroid-cardiac axis in dyslipidemia susceptibility.
The assumption of conditional independence between the responses and the response times (RTs) for a given person is common in RT modeling. However, when the speed of a test taker is not constant, ...this assumption will be violated. In this article we propose a conditional joint model for item responses and RTs, which incorporates a covariance structure to explain the local dependency between speed and accuracy. To obtain information about the population of test takers, the new model was embedded in the hierarchical framework proposed by van der Linden (2007). A fully Bayesian approach using a straightforward Markov chain Monte Carlo (MCMC) sampler was developed to estimate all parameters in the model. The deviance information criterion (DIC) and the Bayes factor (BF) were employed to compare the goodness of fit between the models with two different parameter structures. The Bayesian residual analysis method was also employed to evaluate the fit of the RT model. Based on the simulations, we conclude that (1) the new model noticeably improves the parameter recovery for both the item parameters and the examinees' latent traits when the assumptions of conditional independence between the item responses and the RTs are relaxed and (2) the proposed MCMC sampler adequately estimates the model parameters. The applicability of our approach is illustrated with an empirical example, and the model fit indices indicated a preference for the new model.
Limited research has been conducted on the potential relationship between the dietary inflammation index (DII) and mortality, particularly in individuals with Helicobacter pylori (H. pylori) ...infection. This study aimed to investigate the association between the DII and H. pylori infection, as well as their respective impacts on all-cause mortality in a cohort of individuals with or without H. pylori infection.
Data from the 1999-2018 National Health and Nutrition Examination Survey (NHANES) were utilized for this study, with a final of 4370 participants included. Both univariable and multivariable-adjusted logistic regression analyses were employed to explore the relationship between H. pylori infection and pertinent covariates. Cox regression analysis, as well as restricted regression cubic spline analysis, were utilized to assess the association between DII and all-cause mortality among individuals with or without H. pylori infection.
The findings demonstrated a positive correlation between DII scores and H. pylori infection, even after adjusting for potential confounding factors. Moreover, higher DII scores were significantly associated with an elevated risk of mortality exclusively in individuals with H. pylori infection, while no such association was observed in the uninfected population. Additional analysis using restricted cubic spline modeling revealed a positive linear relationship between DII scores as a continuous variable and the adjusted risk of all-cause mortality specifically in H. pylori-infected patients.
The results of this study indicated that DII was positively correlated with an increased risk of H. pylori infection and was associated with a heightened risk of all-cause mortality solely in individuals with H. pylori infection. Consequently, DII might serve as a useful tool for risk stratification in the H. pylori-infected population among U.S. adults. Further research is warranted to elucidate the underlying mechanisms and potential clinical implications of these findings.
Familial hypercholesterolemia (FH) is an inherited metabolic disorder with a high level of low-density lipoprotein cholesterol and the worse prognosis. The triglyceride-glucose (TyG) index, an ...emerging tool to reflect insulin resistance (IR), is positively associated with a higher risk of atherosclerotic cardiovascular disease (ASCVD) in healthy individuals, but the value of TyG index has never been evaluated in FH patients. This study aimed to determine the association between the TyG index and glucose metabolic indicators, insulin resistance (IR) status, the risk of ASCVD and mortality among FH patients.
Data from National Health and Nutrition Examination Survey (NHANES) 1999-2018 were utilized. 941 FH individuals with TyG index information were included and categorized into three groups: < 8.5, 8.5-9.0, and > 9.0. Spearman correlation analysis was used to test the association of TyG index and various established glucose metabolism-related indicators. Logistic and Cox regression analysis were used to assess the association of TyG index with ASCVD and mortality. The possible nonlinear relationships between TyG index and the all-cause or cardiovascular death were further evaluated on a continuous scale with restricted cubic spline (RCS) curves.
TyG index was positively associated with fasting glucose, HbA1c, fasting insulin and the homeostatic model assessment of insulin resistance (HOMA-IR) index (all p < 0.001). The risk of ASCVD increased by 74% with every 1 unit increase of TyG index (95%CI: 1.15-2.63, p = 0.01). During the median 114-month follow-up, 151 all-cause death and 57 cardiovascular death were recorded. Strong U/J-shaped relations were observed according to the RCS results (p = 0.0083 and 0.0046 for all-cause and cardiovascular death). A higher TyG index was independently associated with both all-cause death and cardiovascular death. Results remained similar among FH patients with IR (HOMA-IR ≥ 2.69). Moreover, addition of TyG index showed helpful discrimination of both survival from all-cause death and cardiovascular death (p < 0.05).
TyG index was applicable to reflect glucose metabolism status in FH adults, and a high TyG index was an independent risk factor of both ASCVD and mortality.
Few studies of cryogenic treatment were focused on nonferrous alloys, such as magnesium alloy. In this work, the effect of cryogenic treatment (77 K) before extrusion on microstructure and mechanical ...properties of ZK60 alloy was investigated. The results showed that many fine G.P. zones were formed during the cryogenic treatment and then grew to short fine
precipitates when heating before extrusion. These precipitates pinned dynamic recrystallized grain boundaries in the subsequent extrusion, resulting in fine gains and dispersed spherical precipitates. By the cryogenic treatment before extrusion, the extruded ZK60 alloy showed good tensile strength and elongation balance. Especially, elongation was improved by 29%.
In order to study the level and size distribution of microbial activity of atmospheric bioaerosols, bioaerosol samples were collected from November 2015 to January 2016 using size-fractionated ...bioaerosol samplers at the coastal region of Qingdao, and the microbial activity was measured using the fluorescein diacetate (FDA) hydrolysis method. The results showed that the level of microbial activity was in the range of 21.89-108.59 ng·m
sodium fluorescein during the sampling period, with an average of 59.43 ng·m
sodium fluorescein in Qingdao. Size distribution of microbial activity exhibited a tendency, the activity increased with increasing particle size. The microbial activity on particles with coarse size (>2.1 μm) was higher than that on fine size, with the highest average proportion of 24.06% for coarse size larger than 7.0 μm. The daily variation of microbial activity was different for different samples, which showed no significant diurnal variation in winter. The correlation analysis showed that microbial
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•For the first time, we designed and constructed a series of Ni(OH)2-modified COFs.•Ni(OH)2 acts as noble-metal free cocatalyst in catalyst system.•Ni(OH)2-X%/TpPa-2 photocatalyst is ...comparable to Pt-containing COF-based catalyts.•Ni(OH)2-X%/TpPa-2 photocatalysts master a high rate of electron transport.•The synergistic effect of TpPa-2 and Ni(OH)2 has been systematic studied.
Covalent-organic frameworks (COFs) have been recognized as an emerging type of photocatalysts for H2 evolution and some of them have shown really outstanding photocatalytic activity with the help of Pt co-catalyst. To avoid the utilization of noble metal in COF-based photocatalysts, for the first time, we designed and constructed a series of nickel hydroxide-modified COF (TpPa-2) composite materials Ni(OH)2-X%/TpPa-2 (X: molar fraction of Ni(OH)2), which show apparently improved photocatalytic H2 evolution activity than that of the parent COF and the activity is comparable to that with Pt (0.3 wt%) co-catalyst. A series of Ni(OH)2-X%/TpPa-2 were prepared by in-situ adding TpPa-2 into the reaction system of Ni(OH)2, and the resulting Ni(OH)2-X%/TpPa-2 exhibit a novel sandwich-like morphology. The results of photocatalytic hydrogen evolution under visible light irradiation show that the optimized photocatalytic H2-evolution rate for Ni(OH)2–2.5%/TpPa-2 is up to 1895.99 μmol·h−1·g−1, which is about 26.3 times higher than that of the parent TpPa-2 and is one of the best performing 2D COF-based photocatalyst for H2 evolution. Further investigation confirm the improved activity should be attributed to the enhanced visible-light absorption of the composite materials contributed from Ni(OH)2 and the synergetic effect of Ni(OH)2 and metallic Ni derived from the in-situ reduction of Ni(OH)2, which promoted the separation of photogenerated electron–holes of the resulting materials. This work not only presents a series of new photocatalysts for efficient H2 evolution but also open an avenue for future design and synthesis of COF-based composite materials acting as a substitute of noble-metal-containing photocatalytic systems.
Nobel metallic Pt/ZSM-22 and Pt/ZSM-23 catalysts were prepared for hydroisomerization of normal dodecane and hydrodewaxing of heavy waxy lube base oil. The hydroisomerization performance of ...n-dodecane indicated that the Pt/ZSM-23 catalyst preferred to crack the C–C bond near the middle of
n
-dodecane chain, while the Pt/ZSM-22 catalyst was favorable for breaking the carbon chain near the end of
n
-dodecane. As a result, more than 2% of light products (gas plus naphtha) and 3% more of heavy lube base oil with low-pour point and high viscosity index were produced on Pt/ZSM-22 than those on Pt/ZSM-23 while using the heavy waxy vacuum distillate oil as feedstock.
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