Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Small ; : e2311555, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651533

RESUMEN

Ultramicroporous metal-organic frameworks (MOFs) are demonstrated to be advantageous for the separation and purification of light hydrocarbons such as C2H2, C2H4, and CH4. The introduction of transition metal sites with strong π-complexation affinity into MOFs is more effective than other adsorption sites for the selective adsorption of π-electron-rich unsaturated hydrocarbon gases from their mixtures. However, lower coordination numbers make it challenging to produce robust MOFs directly utilizing metal ions with π-coordination activity, such as Cu+, Ag+, and Pd2+. Herein, a series of novel π-complexing MOFs (SNNU-33s) with a pore size of 4.6 Å are precisely constructed by cleverly introducing symmetrically matched C3-type [Cu(pyz)3] (pyz = pyrazine) coordinated fragments into 1D hexagonal channels of MIL-88 prototype frameworks. Benifit from the spatial confinement combined with π-complex-active Cu+ of [Cu(pyz)3], pore-space-partitioned SNNU-33 MOFs all present excellent C2H2/CH4, C2H4/CH4, and CO2/CH4 separation ability. Notably, the optimized SNNU-33b adsorbent demonstrates top-level IAST selectivity values for C2H2/CH4 (597.4) and C2H4/CH4 (69.8), as well as excellent breakthrough performance. Theoretical calculations further reveal that such benchmark light hydrocarbon separation and purification ability is mainly ascribed to the extra-strong binding affinity between Cu+ and π-electron donor molecules via a spatially confined π-complexation process.

2.
Anal Chem ; 95(49): 17981-17987, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-38032138

RESUMEN

Despite continuous technological improvements in sample preparation, mass-spectrometry-based proteomics for trace samples faces the challenges of sensitivity, quantification accuracy, and reproducibility. Herein, we explored the applicability of turboDDA (a method that uses data-dependent acquisition without dynamic exclusion) for quantitative proteomics of trace samples. After systematic optimization of acquisition parameters, we compared the performance of turboDDA with that of data-dependent acquisition with dynamic exclusion (DEDDA). By benchmarking the analysis of trace unlabeled human cell digests, turboDDA showed substantially better sensitivity in comparison with DEDDA, whether for unfractionated or high pH fractionated samples. Furthermore, through designing an iTRAQ-labeled three-proteome model (i.e., tryptic digest of protein lysates from yeast, human, and E. coli) to document the interference effect, we evaluated the quantification interference, accuracy, reproducibility of iTRAQ labeled trace samples, and the impact of PIF (precursor intensity fraction) cutoff for different approaches (turboDDA and DEDDA). The results showed that improved quantification accuracy and reproducibility could be achieved by turboDDA, while a more stringent PIF cutoff resulted in more accurate quantification but less peptide identification for both approaches. Finally, the turboDDA strategy was applied to the differential analysis of limited amounts of human lung cancer cell samples, showing great promise in trace proteomics sample analysis.


Asunto(s)
Proteoma , Espectrometría de Masas en Tándem , Humanos , Proteoma/análisis , Espectrometría de Masas en Tándem/métodos , Escherichia coli/metabolismo , Reproducibilidad de los Resultados , Péptidos
3.
Inorg Chem ; 62(37): 15195-15205, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37656912

RESUMEN

Metal-organic frameworks (MOFs) have attracted extensive attention in methane (CH4) purification and storage. Specially, multinuclear cluster-based MOFs usually have prominent performance because of large cluster size and abundant open metal sites. However, compared to diverse combinations of organic linkers, one MOF with two or more multinuclear clusters is difficult to achieve. In this paper, we demonstrate a mixed multinuclear cluster strategy, which successfully led to three new heterometallic MOFs (SNNU-328-330) with the same common H3TATB [2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine] tritopic linker and six types of multinuclear clusters ([YCd(COO)4(µ2-H2O)], [YCd2(COO)8], [In3(COO)6(µ3-OH)], [In3Eu2(COO)9(µ3-OH)3(µ4-O)], [Y9(COO)12(µ3-OH)14] and [Y2Cd8(COO)16(µ2-H2O)4(µ3-OH)8]). Three MOF adsorbents all show great potentials to remove the impurities (CO2 and C2-hydrocarbons) in natural gas and show prominent high-pressure methane storage capacity. Among them, the ideal adsorbed solution theory separation ratios of equimolar C2H2/CH4, C2H4/CH4, C2H6/CH4, and CO2/CH4 at 298 K for SNNU-328 reach to 29.7-16.0, 19.1-8.2, 33.2-10.3, and 74.3-8.5, which have surpassed many famous MOF adsorbents. Dynamic breakthrough experiments conducted at 273 and 298 K showed that SNNU-330 can separate CH4 from C2H2/CH4, C2H4/CH4, C2H6/CH4, and CO2/CH4 mixtures with the breakthrough interval times of about 48.2, 17.9, 37.2, and 17.1 min g-1 (273 K, 1 bar, v/v = 50/50, 2 mL min-1), respectively. Remarkably, SNNU-329 exhibits extremely high methane storage performance at 298 K with the total uptake and working capacity of 192 cm3 cm-3 (95 bar) and 171 cm3 cm-3 (65 bar) due to the synergistic effects of high surface area, suitable pore sizes, and multiple open metal sites.

4.
Altern Ther Health Med ; 29(6): 170-175, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37235498

RESUMEN

Objective: To evaluate the efficacy and safety of the Yinghua tablet in treating sequelae of pelvic inflammatory diseases (PID) that manifest as the syndrome of dampness-heat stasis. Methods: The experimental group enrolled 360 cases, while the control group enrolled 120 cases. The experimental group took Yinghua tablets three times a day, three tablets each time, and the control group took Fuyankang tablets three times a day, three tablets each time. The treatment course was six weeks. Before treatment, at three weeks and six weeks of treatment, the patients were scored for TCM syndrome, clinical symptoms and, signs, and adverse events during treatment were recorded. Results: The experimental group included 340 cases, and the control group finally included 114 cases. After six weeks of treatment, statistically significant differences were observed between the two groups in the treatment effect, recovery rate, markedly effective rate, and total effective rate (P < .05). The two groups had no significant difference in the effective rate of local signs (P > .05). However, the two groups had a significant difference in the total effective rate (P < .05). Before and after treatment, traditional Chinese medicine (TCM) symptoms score, symptom sign score, and local sign score were statistically significant (P < .05). The incidence of adverse events (AEs) after taking Yinghua Tablets was 3.61% (13 times), of which the incidence of adverse events related to study drugs was 0.28% (1 case). The AEs of Fuyankang Tablets were 1.67% (2 times), of which the incidence of adverse events related to study drugs was 1.67% (2 cases). There was no significant difference in the incidence of AEs between the two groups as compared to Fisher (P = .3767), indicating that no serious AEs occurred in either group. Conclusions: Yinghua tablet was effective and safe in treating sequelae of pelvic inflammatory diseases.


Asunto(s)
Enfermedad Inflamatoria Pélvica , Femenino , Humanos , Enfermedad Inflamatoria Pélvica/tratamiento farmacológico , Medicina Tradicional China , Síndrome , Comprimidos
5.
Inorg Chem ; 58(9): 6312-6319, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31017773

RESUMEN

The incorporation of heterometallic atoms into the structure of titanium-oxygen nanomaterials is one of the known and effective strategies to develop new high-performance photovoltaic active materials. In this study, we have synthesized three benzoic acid-stabilized heterometallic titanium oxo clusters with the different transition metals Co, Cu, and Cd, formulated as [Ti4Co2(µ2-O)2(µ3-O)2(C6H5COO)12(CH3CN)2]·2CH3CN (1), [Ti5Cu4(µ3-O)6(C6H5COO)16] (2), and [Ti12Cd5(µ2-O)(µ3-O)15(µ4-O)2(C6H5COO)22(C6H5COOH)(CH3CN)]·CH3CN·C6H5COOH (3), and then we characterized their structures. UV-vis spectroscopy analysis revealed an enhanced UV-vis-light absorption of those heterometallic clusters. The density functional theory calculations indicated that charge transfer occurs from the p orbital of O atoms to the d orbital of Ti atoms in the TiO core (O → Ti) as well as from the metal to the core in 1 and 2. We also measured the photocurrent response and photocatalytic H2 evolution, which shows enhancement in the photocurrent intensity and good H2 evolution ability because of the cooperative effect of heterometal doping in titanium oxo clusters.

6.
Chemistry ; 24(12): 2952-2961, 2018 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-29265501

RESUMEN

The exploitation of new titanium-based coordination polymers (Ti CPs) with high crystallinity is difficult but highly desirable for their potential applications in photocatalysis. Herein, a cluster-cooperative assemble strategy is developed to synthesize Ti CPs. By utilizing various bifunctional ligands containing carboxylate acids and N-donor groups, we successfully assembled the zero-dimensional (0D) [(Ti3 O)(iPrO)8 ]2+ or [(Ti4 O2 )(iPrO)6 ]6+ clusters into one-dimensional (1D) tube-, ribbon-, or helical chain-shape architectures, two-dimensional (2D) layered structures, and a rare parallel 2D→three-dimensional (3D) polycatenation framework with various copper iodide dopants, including rhombus- or wing-shaped Cu2 I2 and tetrahedron- or ladder-shaped Cu4 I4 . The as-synthesized compounds display strong absorption in the visible region with narrow band gaps ranging from 1.70 to 2.72 eV and exhibit good photocatalytic activities in the degradation of organic pollutants.

7.
Chemistry ; 24(3): 699-705, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29071743

RESUMEN

We report the successful isolation and structural elucidation of two bimetallic doped [Co2 @Ge16 ]4- clusters (α and ß form), which were synthesized through the reaction of [{(ArN)2 CtBu}Co(η6 -toluene)] (Ar=2,6-diisopropylphenyl) and K4 Ge9 in ethylenediamine (en) solution and co-crystallized together in [K(2,2,2-crypt)]4 [Co2 @Ge16 ]⋅en. The α-[Co2 @Ge16 ]4- isomer prefers a distinct D2h 3-connected architecture, whereas the deltahedral isomeric ß-[Co2 @Ge16 ]4- isomer adopts a quasi-C2h geometry and can be seen as coupling of two distorted arachno-[Co@Ge10 ] units. Chemical bonding analyses indicate that the skeleton of the α isomer is mainly composed of localized bonds, whereas only multicenter bonding interactions govern the geometry of the ß isomer, which was further found to exhibit a fluxional behavior. The coexistence of both isomers within one unit cell links the 3-connected clusters with their deltahedral congeners, thus highlighting the structural and electronic flexibility of such discreet cluster systems.

8.
Inorg Chem ; 57(6): 3025-3034, 2018 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-29512998

RESUMEN

The binary cluster [Co@Sn9]4- (1) was extracted directly from ethylenediamine (en) solutions of an intermetallic precursor with nominal composition "K5Co3Sn9", and its reactions with various organometallic reagents were explored. Reaction with Ni(PPh3)2(CO)2 gives [Co@Sn9Ni(CO)]3- (2), a Co-centered closo-Sn9Ni bicapped square antiprism. Analogous reactions with Ni(COD)2, Pt(PPh3)4, and Au(PPh3)Ph led to the isolation of [Co@Sn9Ni(C2H4)]3- (3), [Co@Sn9Pt(PPh3)]3- (4), and [Co@Sn9AuPh]3- (5), respectively. 3 is structurally similar to 2 but significantly distorted from a closo-cluster with one open square face. The coordination of [CoSn9]3- by PtPPh3 (4) or AuPh (5) induces a structural transformation in the CoSn9 core, from a monocapped square antiprism ( C4 v) to a tricapped trigonal prismatic structure ( pseudo- C3 v), with the transition metal fragment capping a triangular face. The four trimetallic anions presented here represent a new family of ternary functionalized Zintl clusters incorporating a d9 transition metal center. All clusters were characterized by single-crystal X-ray diffraction and electrospray ionization mass spectrometry (ESI-MS).

9.
Inorg Chem ; 56(3): 1669-1678, 2017 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-28118014

RESUMEN

The hydrothermal reaction of uranyl ions with (5-methyl-1,3-phenylene)diphosphonic acid (H4MPDP) in the presence of additives such as nitric acid, N-bearing species, and heterometal ions yielded five new uranyl organic hybrids: (H3O)[(UO2)5(H2O)4(H3DPB)2(H2DPB)(HDPB)]·2H2O (1), (Hphen)(phen)[(UO2)3(H2DPB)(HDPB)] (2), (H2dipy)[(UO2)3(MPDP)2] (3), Zn(bipy)(UO2)(MPDP) (4), and Co(bipy)(UO2)(MPDP)·H2O (5) (H5DPB = 3,5-diphosphonobenzoic acid; phen = 1,10-phenanthroline; dipy = 4,4'-bipyridine; bipy = 2,2'-bipyridine). Single-crystal X-ray diffraction (XRD) demonstrates that 1 and 2 are 3D frameworks constructed of uranyl centers and carboxyphosphonate DPB ligands; the latter were formed via the in situ oxidation of H4MPDP. In the homometallic uranyl diphosphonate 3, less common UO6 square bipyramids connected by MPDP ligands were incorporated to form the 2D assembly. A further introduction of heterometal ions produced two heterobimetallic uranyl phosphonates 4 and 5. Both of them show layered structures, formed by UO6 square bipyramids linked by MPDP ligands with heterometal-centered polyhedra decorated on the sides of the layers. It is found that the pH and heterometal ions have significant effects on the structures of the complexes. In addition to the syntheses and XRD characterization, the spectroscopic properties of these uranyl complexes were also addressed. To complement the experimental results, density functional theory calculations were carried out on several model complexes that feature a homo- or heterobimetallic molecular skeleton. Geometrical/electronic structures, IR spectra, and electronic absorptions were discussed.

10.
Med Sci Monit ; 23: 3044-3053, 2017 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-28638006

RESUMEN

BACKGROUND It has been unclear whether supplemental probiotics therapy improves clinical outcomes in type 2 diabetic patients. This meta-analysis aimed to summarize the effect of probiotics on glucose and lipid metabolism and C-reactive protein (CRP) from 12 randomized controlled trials (RCTs). MATERIAL AND METHODS An up-to-date search was performed for all relevant RCTs up to April 2016 from PubMed, Embase, and Cochrane Library. Standardized mean difference (SMD) and weighted mean difference (WMD) were calculated for a fixed-effect and random-effect meta-analysis to assess the impact of supplemental probiotics on fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), lipid profile, and CRP level. RESULTS A total of 12 studies (684 patients) were entered into the final analysis. The effect of probiotics was significant on reducing HbA1c level (standardized mean difference [SMD], -0.38; confidence interval [CI], -0.62 to -0.14, P=0.002; I²=0%, P=0.72 for heterogeneity), fasting insulin level (SMD, -0.38; CI -0.59 to -0.18, P=0.0003; I²=0%, P=0.81 for heterogeneity), and HOMA-IR (SMD, -0.99; CI -1.52 to -0.47, P=0.0002; I²=86%, P<0.00001 for heterogeneity). Pooled results on effects of probiotics on FPG, CRP, or lipid profile were either non-significant or highly heterogeneous. CONCLUSIONS This meta-analysis demonstrated that probiotics supplementation was associated with significant improvement in HbA1c and fasting insulin in type 2 diabetes patients. More randomized placebo-controlled trials with large sample sizes are warranted to confirm our conclusions.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Probióticos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/sangre , Humanos , Lípidos/sangre , Probióticos/farmacología , Sesgo de Publicación , Factores de Riesgo
11.
Chemistry ; 22(33): 11652-9, 2016 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-27374008

RESUMEN

A Mn(II) phosphonate of the general formula [Mn(H2 L)2 (H2 O)2 (H2 bibp)] adopts a layered motif with protonated H2 bibp(2+) cations embedded in the channels (H4 L=thiophene-2-phosphonic acid; bibp=4,4'-bis(1-imidazolyl)biphenyl). The title compound exhibits excellent adsorptive removal of methyl orange (MO) dye from aqueous solution. Its advantageous features include fast adsorption, high uptake capacity, selective removal, and reusability, which are of great significance for practical application in wastewater treatment. Meanwhile, the compound displays rapid photochromism upon irradiation with visible light at room temperature. Extensive research has demonstrated that such behavior is based on a ligand-to-ligand charge-transfer (LLCT) mechanism. The irradiated sample possesses an ultra-long-lived charge-separated state. Moreover, not only is the compound the first Mn-based photochromic MOF, but it is also one of the very few examples showing LLCT with non-photochromic components.

12.
Inorg Chem ; 55(2): 537-9, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26699733

RESUMEN

A 3D chiral cobalt phosphonate has been obtained from achiral precursors in the absence of chiral inducers. Remarkably, the bulk sample is largely enantio-enriched with particular handedness through symmetry-breaking crystallization in spite of multiple repeated experiments. Moreover, protonation of this chiral material introduces Brønsted acid sites, the structure of which is unique to the heterogeneous phase for the ring opening of epoxies.

13.
Phys Chem Chem Phys ; 18(28): 18683-6, 2016 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-27375165

RESUMEN

Negative ion photoelectron spectroscopy shows interesting regioisomer-specific electron affinities (EAs) of 2,5- and 7,23-para-adducts of C70 [(ArCH2)2C70] (Ar = Ph, o-, m-, and p-BrC6H4). Their EA values are larger than that of C70 by 5-150 meV with the 2,5-polar adducts' EAs being higher than their corresponding 7,23-equatorial counterparts, exhibiting appreciable EA tunable ranges and regioisomeric specificity. Density functional theory (DFT) calculations reproduce both the experimental EA values and EA trends very well.

14.
Angew Chem Int Ed Engl ; 55(49): 15344-15346, 2016 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-27862764

RESUMEN

Gas-phase clusters are deemed to be σ-aromatic when they satisfy the 4n+2 rule of aromaticity for delocalized σ electrons and fulfill other requirements known for aromatic systems. While the range of n values was shown to be quite broad when applied to short-lived clusters found in molecular-beam experiments, stability of all-metal cluster-like fragments isolated in condensed phase was previously shown to be mainly ascribed to two electrons (n=0). In this work, the applicability of this concept is extended towards solid-state compounds by demonstrating a unique example of a storable compound, which was isolated as a stable [K([2.2.2]crypt)]+ salt, featuring a [Au2 Sb16 ]4- cluster core possessing two all-metal aromatic AuSb4 fragments with six delocalized σ electrons each (n=1). This discovery pushes the boundaries of the original idea of Kekulé and firmly establishes the usefulness of the σ-aromaticity concept as a general idea for both small clusters and solid-state compounds.

15.
Angew Chem Int Ed Engl ; 55(18): 5531-5, 2016 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-27062366

RESUMEN

Antiaromaticity, as introduced in 1965, usually refers to monocyclic systems with 4n π electrons. This concept was extended to all-metal molecules after the observation of Li3 Al4 (-) in the gas phase. However, the solid-phase counterparts have not been documented to date. Herein, we describe a series of all-metal antiaromatic anions, [Ln(η(4) -Sb4 )3 ](3-) (Ln=La, Y, Ho, Er, Lu), which were isolated as the K([2.2.2]crypt) salts and identified by single-crystal X-ray diffraction. Based on the results obtained from the chemical bonding analysis, multicenter indices, and the electron-counting rule, we conclude that the core [Ln(η(4) -Sb4 )3 ](3-) fragment of the crystal has three locally π-antiaromatic Sb4 fragments. This complex represents the first locally π-antiaromatic all-metal system in the solid state, which is stabilized by interactions of the three π-antiaromatic units with the central metal atom.

16.
J Am Chem Soc ; 137(34): 10954-7, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26275027

RESUMEN

A sandwich complex, as exemplified by ferrocene in the 1950s, usually refers to one metal center bound by two arene ligands. The subject has subsequently been extended to carbon-free aromatic ligands and multiple-metal-atom "monolayered" center, but not to an all-metal species. Here, we describe the synthesis of an unprecedented all-metal aromatic sandwich complex, [Sb3Au3Sb3](3-), which was isolated as K([2.2.2]crypt)(+) salt and identified by single-crystal X-ray diffraction. Quantum chemical calculations indicate that intramolecular electron transfers for the three metallic layers (Sb → Au donation and Sb ← Au back-donation) markedly redistribute the valence electrons from the cyclo-Sb3 ligands and Au3 interlayer to the Au-Sb bonds, which hold the complex together via σ bonding. Each cyclo-Sb3 possesses aromaticity with delocalized three-center three-electron (3c-3e) π bonds, which are essentially equivalent to a 3c-4e ππ* triplet system, following the reversed 4n Hückel rule for aromaticity in a triplet state.

17.
Plant Sci ; 338: 111916, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37944704

RESUMEN

DNA N6-methyladenine (6 mA) is an evolutionarily conserved DNA modification in procaryotes and eukaryotes. The DNA 6 mA methylation is tightly controlled by 6 mA regulatory proteins. DNA N6-adenine methyltransferase 1 (DAMT-1) has been identified as a DNA 6 mA methyltransferase in animals. In plants, DNA 6 mA methylation has been found, however, the DNA 6 mA methyltransferases and their function in plants are largely unknown. In our study, we find METTL4 is a DNA 6 mA methyltransferase in Arabidopsis thaliana. Both in vitro and in vivo evidences support the DNA 6 mA methyltransferase activity of METTL4. mettl4 mutant is hypersensitive to heat stress, suggesting DNA 6 mA methylation plays important role in heat stress adaption. RNA-seq and 6 mA IP-qPCR analysis show that METTL4 participates in heat stress tolerance by regulating expression of heat responsive genes. Our study find METTL4 is a plant DNA 6 mA methyltransferase and illustrates its function in regulating heat stress response.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Termotolerancia , Animales , Arabidopsis/metabolismo , Termotolerancia/genética , Proteínas de Arabidopsis/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Plantas/metabolismo , ADN/metabolismo , Regulación de la Expresión Génica de las Plantas
18.
Foods ; 12(14)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37509736

RESUMEN

Aflatoxin B1 (AFB1), as a class I carcinogen, poses a substantial health risk to individuals. Contamination of food sources, particularly grains and nuts, with Aspergillus flavus (A. flavus) contributes to the prevalence of AFB1. The impact of global warming has spurred research into the development of AFB1 prevention technologies. While edible fungi have shown potential in detoxifying AFB1, there is a scarcity of literature on the application of Auricularia auricular (A. auricular) in this context. This study aimed to investigate the ability and underlying mechanism of A. auricular mycelia to adsorb aflatoxin B1, as well as evaluate its protective effects on the AFB1-induced liver damage in SD rats. Additionally, the effects of temperature, time, pH, and reaction ratio on the adsorption rate were examined. Combining thermodynamic and kinetic data, the adsorption process was characterized as a complex mechanism primarily driven by chemical adsorption. In SD rats, the A. auricular mycelia exhibited alleviation of AFB1-induced liver damage. The protective effects on the liver attributed to A. auricular mycelia may involve a reduction in AFB1 adsorption in the intestine, mitigation of oxidative stress, and augmentation of second-phase detoxification enzyme activity. The adsorption method for AFB1 not only ensures safety and non-toxicity, but also represents a dietary regulation strategy for achieving effective defense against AFB1.

19.
J Mater Chem B ; 11(43): 10455-10463, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37888984

RESUMEN

Bio-patches for the treatment of valvular disease have been evaluated in clinical trials. It has been shown that failure of these devices, occurring within a few years of implantation, may be due to cytotoxicity, immune response, calcification and thrombosis. Some of these effects may be due to the glutaraldehyde crosslinking process used in the preparation of the materials. A number of studies have focused on strategies to control calcification, while others have concentrated on the prevention of micro-thrombus formation. In the present work, we have introduced amino-terminated poly(ethylene glycol) (NH2-PEG-NH2) as an intermolecular bridge, which not only eliminates free aldehyde groups to prevent calcification, but also introduces sites for the attachment of anticoagulant molecules. Furthermore, PEG, itself a hydrophilic polymer with good biocompatibility, may effectively prevent protein adsorption in the early stages of blood contact leading to thrombus formation. After further covalent attachment of heparin, modified bovine pericardium (BP) showed strong anti-calcification (calcium content: 39.3 ± 3.1 µg mg-1) and anti-coagulation properties (partial thromboplastin time: >300 s). The biocompatibility and mechanical properties, important for clinical use, were also improved by modification. The strategy used in this work includes new ideas and technologies for the improvement of valve products used in the clinic.


Asunto(s)
Calcinosis , Trombosis , Animales , Bovinos , Calcificación Fisiológica , Calcinosis/metabolismo , Calcinosis/prevención & control , Calcio/metabolismo , Glutaral
20.
Biomater Adv ; 154: 213664, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37866231

RESUMEN

Molecular patterning on biomaterial surfaces is an effective strategy to regulate biomaterial properties. Among the specific molecules, due to their biological functions, such as regulating cell behavior, heparin-like polymers (HLPs) have attracted much attention. In this study, HLP-distributed regional patterned surfaces (300 µm diameter circular array) were prepared by the combination of visible light-induced graft polymerization, transfer imprinting, and self-assembly to regulate the behavior of human umbilical vein endothelial cells (HUVECs) and human umbilical vein smooth muscle cells (HUVSMCs). The introduction of the regional pattern on HLP-modified surfaces enhanced the promotion effect of sulfonate-containing polymer (pSS) and sulfonate-, and glyco-containing copolymer (pS-co-pM), and slightly weakened the inhibition effect of glyco-containing polymer (pMAG) on the growth of HUVECs and HUVSMCs. Compared with flat surfaces, it was found that the unmodified regional patterned surfaces inhibit the spreading of HUVECs and HUVSMCs, while significantly promoting the spreading of HUVECs and HUVSMCs on all the HLP-distributed regional patterned surfaces. The patterned surface modified with pS-co-pM had the highest average spread area of HUVECs (∼10,554 µm2), which was 193 % higher than that of the unmodified flat surface. This trend was somewhat related to surface VEGF adsorption. The combination of regional divisive patterns and different HLP distributions enriched the potential of further exploring the influences of HLP chemical distributions and complex surface environments on cell-material interactions.


Asunto(s)
Heparina , Polímeros , Humanos , Polímeros/farmacología , Heparina/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Materiales Biocompatibles/farmacología , Luz
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA