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1.
Small Methods ; : e2301229, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528393

RESUMO

The charge-transfer (CT) interactions between organic compounds are reflected in the (opto)electronic properties. Determining and visualizing crystal structures of CT complexes are essential for the design of functional materials with desirable properties. Complexes of pyranine (PYR), methyl viologen (MV), and their derivatives are the most studied water-based CT complexes. Nevertheless, very few crystal structures of CT complexes have been reported so far. In this study, the structures of two PYRs-MVs CT crystals and a map of the noncovalent interactions using 3D electron diffraction (3DED) are reported. Physical properties, e.g., band structure, conductivity, and electronic spectra of the CT complexes and their crystals are investigated and compared with a range of methods, including solid and liquid state spectroscopies and highly accurate quantum chemical calculations based on density functional theory (DFT). The combination of 3DED, spectroscopy, and DFT calculation can provide important insight into the structure-property relationship of crystalline CT materials, especially for submicrometer-sized crystals.

2.
Inorg Chem ; 62(49): 20314-20324, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37991983

RESUMO

Functionalized crystalline solids based on metal-organic frameworks (MOFs) enable efficient luminescence detection and high proton conductivity, making them crucial in the realms of environmental monitoring and clean energy. Here, two structurally and functionally distinct zinc-based MOFs, [Zn(TTDPa)(bodca)]·H2O (1) and [Zn(TTDPb)(bodca)]·H2O (2), were successfully designed and synthesized using 3,6-di(pyridin-4-yl)thieno[3,2-b]thiophene (TTDPa) and 2,5-di(pyridin-4-yl)thieno[3,2-b]thiophene (TTDPb) as ligands, in the presence of bicyclo[2.2.2]octane-1,4-dicarboxylic acid (H2bodca). Both 1 and 2 display a three-dimensional (3D) structure with 5-fold interpenetration, and notably, 2 forms a larger one-dimensional pore measuring 17.16 × 10.81 Å2 in size. Fluorescence experiments demonstrate that 1 and 2 can function as luminescent sensors for nitrofurantoin (NFT) and nitrofurazone (NFZ) with low detection limits, remarkable selectivity, and good recyclability. A comprehensive analysis was conducted to investigate the differing sensing effects of compounds 1 and 2 and to explore potential sensing mechanisms. Additionally, at 328 K and 98% relative humidity, 1 and 2 exhibit proton conductivity values of 2.13 × 10-3 and 4.91 × 10-3 S cm-1, respectively, making them suitable proton-conducting materials. Hence, the integration of luminescent sensing and proton conductivity in monophasic 3D Zn-MOFs holds significant potential for application in intelligent multitasking devices.

4.
Inorg Chem ; 62(42): 17041-17045, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37819767

RESUMO

The selective fluorination of C-H bonds at room temperature using heterogeneous visible-light catalysts is both interesting and challenging. Herein, we present the heterogeneous sandwich-type structure uranyl-polyoxotungstate cluster Na17{Na@[(SbW9O33)2(UO2)6(PO3OH)6]}·46H2O (denoted as U6P6) to regulate the selective fluorination of the C-H bond under visible light and room temperature. This is the first report in which uranyl participates in the fluorination reaction in the form of an insoluble substance. U6P6 is capable of the effective selective fluorination of cycloalkanes and the recyclability of the photocatalyst due to the synergistic effect of multiple uranyl (UO2)2+ and the insolubility of organic reagents of polyoxotungstate. In situ electron paramagnetic resonance spectroscopy captured the generation of cycloalkane radicals during the photoreaction, confirming the mechanism of direct hydrogen atom transfer.

5.
Inorg Chem ; 62(44): 18209-18218, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37861751

RESUMO

A luminescent Tb-MOF with excellent stability and dual-emitting properties was constructed with an amide-functionalized tetracarboxylate ligand. Tb-MOFs were initially assembled on one-dimensional Tb3+ chains, then formed a two-dimensional double-decker layer through the synergistic linking of organic ligands and bridging formic acid anions, and further fabricated the final three-dimensional structure through the connection of the organic ligands. Powder X-ray diffraction experiments revealed that Tb-MOFs not only exhibited excellent stability in water but also maintained structural integrity in the pH range of 2-12. Importantly, this Tb-MOF provided the first example of a metal-organic framework (MOF)-based luminescence sensor that can simultaneously detect two acid amino acids (aspartic and glutamic acids) through a turn-off sensing mechanism and two basic amino acids (lysine and arginine acids) through unusual turn-on and turn-off-on sensing mechanisms. Moreover, high sensitivity, low detection limit, and excellent recyclability of this sensor endow Tb-MOFs with great potential as a highly efficient amino acid fluorescence sensor in chemical detection and biological environments.

6.
Molecules ; 28(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687019

RESUMO

Alginate oligosaccharides (AOs) prepared through enzymatic reaction by diverse alginate lyases under relatively controllable and moderate conditions possess versatile biological activities. But widely used commercial alginate lyases are still rather rare due to their poor properties (e.g., lower activity, worse thermostability, ion tolerance, etc.). In this work, the alginate lyase Alyw208, derived from Vibrio sp. W2, was expressed in Yarrowia lipolytica of food grade and characterized in order to obtain an enzyme with excellent properties adapted to industrial requirements. Alyw208 classified into the polysaccharide lyase (PL) 7 family showed maximum activity at 35 °C and pH 10.0, indicating its cold-adapted and high-alkaline properties. Furthermore, Alyw208 preserved over 70% of the relative activity within the range of 10-55 °C, with a broader temperature range for the activity compared to other alginate-degrading enzymes with cold adaptation. Recombinant Alyw208 was significantly activated with 1.5 M NaCl to around 2.1 times relative activity. In addition, the endolytic Alyw208 was polyG-preferred, but identified as a bifunctional alginate lyase that could degrade both polyM and polyG effectively, releasing AOs with degrees of polymerization (DPs) of 2-6 and alginate monomers as the final products (that is, DPs 1-6). Alyw208 has been suggested with favorable properties to be a potent candidate for biotechnological and industrial applications.


Assuntos
Alginatos , Oligossacarídeos , Polimerização , Polissacarídeo-Liases
7.
Org Lett ; 25(32): 5963-5968, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37540111

RESUMO

A palladium-catalyzed asymmetric annulative dearomatization of phenols with butene dicarbonate is reported, enabling twofold decarboxylative allylation to regioselectively produce a range of spirocyclohexadienones with 29-95% yields and 74-99% ee. A catalytic dearomative formal [4 + 2] cyclization of 1,1'-biphenyl-2,4'-diols delivered spiro[chromane-4,1'-cyclohexane]-2',5'-dien-4'-ones with high enantioselectivity, whereas enantioenriched spiro[cyclohexane-1,4'-quinoline]-2,5-dien-4-ones were generated starting from 2'-amino-[1,1'-biphenyl]-4-ols as 1,4-dinucleophiles.

8.
Asia Pac J Oncol Nurs ; 10(8): 100255, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37519402

RESUMO

Objective: To validate the Chinese version of the Quality of Life (QoL) Patient/Cancer Survivor Version (QOLCSV-C) for measuring QoL in Chinese cancer survivors. Methods: The study followed a seven-step research practice guideline for cross-cultural research instrument validation study including translation, adaptation, and psychometric assessment. A forward- and backward-translation procedure was approached, followed by cultural adaptation and acceptability assessment. For its psychometric properties, its concurrent validity with the Functional Assessment of Cancer Therapy-General (FACT-G) was examined with correlation analysis. The internal consistency (Cronbach's alpha) and item-total and item-subtotal correlations of the QOLCSV-C were obtained. Factor analyses were conducted. Floor and ceiling effects and the discriminant performance of the selected variables on QOLCSV-C score were also examined. Results: The QOLCSV-C was translated from the 41-item QOLCSV with four domains: psychological, physical, spiritual and social well-being. The content validity was excellent (CVI â€‹= â€‹1.00). Time spent to complete the QOLCSV-C was about 10 â€‹min. The QOLCSV-C was found easy to use, appropriate in length, and reflective of their QoL. The strong correlation between QOLCSV-C and FACT-G indicates a satisfactory concurrent validity (Spearman's rho â€‹= â€‹0.765, P â€‹< â€‹0.001, n â€‹= â€‹205). The overall internal consistency of the QOLCSV-C (Cronbach's alpha â€‹= â€‹0.888) and the split-half reliability (Spearman-Brown r â€‹= â€‹0.918) were excellent. Most of the items show moderate to strong item-total correlation. The exploratory factor analysis revealed a four-factor solution, and confirmatory factor analysis has a satisfactory model fit with indicative items. None of the total scores of QOLCSV-C reveal the floor or ceiling effect. For discriminant performance, variables demonstrating significant between-group differences include sleep quality, pain, fatigue, nausea, physical health, and financial burden. Conclusions: The QOLCSV-C is a reliable and valid instrument for measuring the QoL in Chinese cancer survivors. Future studies can explore the factor structure, gender universal or specific items, and significant predictors of QoL of cancer survivors in different cultures.

9.
J Org Chem ; 88(16): 11913-11923, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37498087

RESUMO

An NHC-catalyzed atroposelective synthesis of axially chiral α-carbolinones from α,ß-unsaturated iminoindole derivatives and α-chloroaldehydes was developed. The reaction proceeds through a cascade process including [4 + 2] annulation and then oxidative dehydrogenation with concomitant central-to-axial chirality conversion under mild conditions. The developed method opens a new avenue to efficiently access axially chiral α-carbolinones in moderate to good enantioselectivities.

10.
Nat Commun ; 14(1): 4044, 2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422483

RESUMO

Direct synthesis of ketones from aldehydes features high atom- and step-economy. Yet, the coupling of aldehydes with unactivated alkyl C(sp3)-H remains challenging. Herein, we develop the synthesis of ketones from aldehydes via alkyl C(sp3)-H functionalization under photoredox cooperative NHC/Pd catalysis. The two-component reaction of iodomethylsilyl alkyl ether with aldehydes gave a variety of ß-, γ- and δ-silyloxylketones via 1,n-HAT (n = 5, 6, 7) of silylmethyl radicals to generate secondary or tertiary alkyl radicals and following coupling with ketyl radicals from aldehydes under photoredox NHC catalysis. The three-component reaction with the addition of styrenes gave the corresponding ε-hydroxylketones via the generation of benzylic radicals by the addition of alkyl radicals to styrenes and following coupling with ketyl radicals. This work demonstrates the generation of ketyl radical and alkyl radical under the photoredox cooperative NHC/Pd catalysis, and provides two and three component reactions for the synthesis of ketones from aldehydes with alkyl C(sp3)-H functionalization. The synthetic potential of this protocol was also further illustrated by the late-stage functionalization of natural products.


Assuntos
Aldeídos , Cetonas , Paládio , Oxirredução , Catálise
11.
Front Mol Biosci ; 10: 1211621, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37363404

RESUMO

Introduction: Tannase is a crucial enzyme that finds wide applications in the pharmaceutical industry, feed processing, and beverage manufacturing. Although extensive studies have been conducted on tannases from fungi and bacteria, reports on tannases exhibiting favorable pH stability are relatively limited. Methods: In this study, a tannin-degrading strain Debaryomyces hansenii was screened to induce tannase production, and the corresponding tannase coding gene TANF was successfully cloned and expressed in Yarrowia lipolytica. SDS-PAGE analysis revealed that the purified TanF tannase had a molecular weight of approximately 70 kDa. Results and Discussion: The enzyme demonstrated optimal activity at 40°C and retained over 80% of its activity in the range of 35°C-60°C. Of particular interest, TanF exhibited remarkable enzyme activity at pH 5.0 and retained more than 70% of its relative activity across a wide pH range of 3.0-8.0. Furthermore, TanF exhibited broad substrate specificity for gallate esters. The final gallic acid production by TanF from tannic acid achieved 18.32 g/L. Therefore, the excellent properties TanF has been demonstrated to be an efficient tool for the preparation of gallic acid.

12.
J Microbiol Immunol Infect ; 56(4): 747-756, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37080838

RESUMO

BACKGROUND: More and more novel anticancer drugs have been approved for patients with hematological malignancies in recent years, but HBV reactivation (HBV-R) data in this population is very scarce. This study aimed to evaluated HBV-R risk in patients with hematological malignancies receiving novel anticancer drugs. METHODS: HBV markers and serum HBV DNA levels of patients with hematological malignancies receiving novel anticancer drugs in a tertiary cancer hospital were retrospectively collected. HBV-R risk in the whole cohort and subgroups was described. The relevant literature was reviewed to make a pooled analysis. RESULTS: Of 845 patients receiving novel anticancer drugs, 258 (30.5%) were considered at risk for HBV-R. The median duration of exposure to novel drugs was 5.6 (0.1-67.6) months. The incidence of HBV-R was 2.1% in patients with past HBV infection without prophylactic antiviral treatment (PAT) and 1.2% in all patients at risk of HBV-R. In a pooled analysis of 11 studies with 464 patients, the incidence of HBV-R was 2.4% (95% CI: 1.3-4.2) in all at-risk patients receiving novel anticancer drugs and 0.6% (95% CI: 0.03-3.5) in patients with anticancer drugs plus PAT. The incidence of death due to HBV-R was 0.4% (95% CI: 0.1-1.6) in all at-risk patients and 18.2% (95% CI: 3.2-47.7) in patients with HBV-R. CONCLUSION: Most episodes of HBV-R are preventable, and most cases with HBV-R are manageable. We recommend that novel anticancer drugs should not be intentionally avoided when treating cancer patients with HBV infection.


Assuntos
Antineoplásicos , Neoplasias Hematológicas , Hepatite B , Neoplasias , Humanos , Vírus da Hepatite B/genética , Incidência , Estudos Retrospectivos , Antineoplásicos/efeitos adversos , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Antivirais/uso terapêutico , Antivirais/farmacologia , Ativação Viral , Hepatite B/tratamento farmacológico , Hepatite B/epidemiologia , Antígenos de Superfície da Hepatite B
13.
Bioresour Technol ; 379: 128984, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37003453

RESUMO

Pelagic Sargassum is invasive macroalgae with huge biomass. To produce bulk chemicals with profit from the biomass, innovative strategies need to be developed. In this study, maximum saccharification yield of Sargassum horneri biomass was obtained with the combined use of 3% alginate lyase and 3% cellulase, releasing 20.83 g/L glucose and 1.73 g/L mannitol at a 1:6 feed ratio. Subsequently, the crude S. horneri hydrolysate (pH 3.0) was proved most suitable for erythritol production of Yarrowia lipolytica strain. After 60 h fermentation in a 10-L fermenter, the erythritol concentration reached 18.42 g/L with a yield of 0.82 g/g; while the concentration of alginate oligosaccharides (AOS) was 37.56 g/L. Finally, AOS with a purity of 93.4% were obtained by ethanol precipitation, and erythritol was harvested via crystallization. This proposed strategy demonstrates the feasibility of transforming invasive Sargassum into two high-value chemicals for the first time.


Assuntos
Sargassum , Yarrowia , Alginatos , Eritritol , Reatores Biológicos , Oligossacarídeos
14.
Org Lett ; 24(42): 7747-7751, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36264013

RESUMO

An N-heterocyclic carbene-catalyzed three-component reaction of ketone, acetylenedicarboxylate, and enal for the synthesis of multisubstituted benzenes has been developed. The key features of this reaction are mild reaction conditions and high efficiency and chemoselectivity. The corresponding pentasubstituted benzenes are obtained in good to high yields.

15.
Phytochem Anal ; 33(8): 1214-1224, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36131366

RESUMO

INTRODUCTION: The total lignans from Fructus arctii (TLFA) is a mixture of a series of lignans isolated from dried ripe fruit of Arctium lappa L. We previously reported on the pharmacological activity of TLFA that is related to diabetes. An accurate and practical TLFA quantitative analysis method for utilising it needs to be established. OBJECTIVE: This study aimed to develop an effective quantitative analysis method for assessing the TLFA quality. METHODS: A total of 11 marker components were confirmed by analysing the high-performance liquid chromatography fingerprints of 24 batches of TLFA samples. The samples were prepared from TLFA and structurally identified as lappaol H, lappaol C, arctiin, arctignan D, arctignan E, matairesinol, arctignan G, isolappaol A, lappaol A, arctigenin, and lappaol F. In the quantitative analysis of multi-components by the single-marker (QAMS) method and with arctiin as an internal reference substance, the content of these lignans in TLFA was simultaneously determined according to their relative correction factors with arctiin. RESULTS: There was no significant difference between results measured by the QAMS and traditional external standard methods. Hierarchical cluster and principal component analyses were performed to evaluate 24 TLFA batches based on the contents of 10 marker components. The results revealed that QAMS method combined with chemometric analyses could accurately measure and clearly distinguish the different quality samples of TLFA. CONCLUSION: The QAMS method is a reliable and promising quality control method for TLFA. It can provide a reference for promoting quality control of complex multi-component systems, especially for traditional Chinese medicine.


Assuntos
Arctium , Medicamentos de Ervas Chinesas , Lignanas , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Lignanas/análise , Arctium/química , Controle de Qualidade , Medicamentos de Ervas Chinesas/química
16.
World J Clin Cases ; 10(26): 9390-9397, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36159444

RESUMO

BACKGROUND: Congenital adrenal hyperplasia (CAH), which is caused by a mutation of the steroidogenic acute regulatory (StAR) gene. Affected patients are usually characterized by adrenal insufficiency in the first year of life, salt loss, glucocorticoid and mineralocorticoid deficiency, and female external genitalia, regardless of chromosomal karyotype. Patients with non-classical lipoid CAH usually develop glucocorticoid deficiency and mild mineralocorticoid deficiency at 2-4 years of age. CASE SUMMARY: Herein, We report the case of a woman with non-classic lipoid CAH combined with Graves' disease. Her chromosome karyotype was 46, XX, and high-throughput sequencing revealed two missense variants in the StAR gene: c.229C > T (p.Q77X) and c.814C > T (p.R272C), which were inherited from both parents (non-close relatives). The patient was treated for Graves' disease in a timely manner and the dosage of glucocorticoid was adjusted during the treatment of Graves' disease. CONCLUSION: This is the first case of non-classic lipoid CAH combined with Graves' disease reported in the Chinese population. In addition to conventional glucocorticoid replacement therapy, timely adjustments were made to the dosages of thyroid hormone and glucocorticoid to avoid adrenal crisis as a consequence of the increased demand and accelerated metabolism of glucocorticoids when the patient was diagnosed with Graves' disease.

17.
Sensors (Basel) ; 22(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35890952

RESUMO

Human motion recognition based on wearable devices plays a vital role in pervasive computing. Smartphones have built-in motion sensors that measure the motion of the device with high precision. In this paper, we propose a human lower limb motion capture and recognition approach based on a Smartphone. We design a motion logger to record five categories of limb activities (standing up, sitting down, walking, going upstairs, and going downstairs) using two motion sensors (tri-axial accelerometer, tri-axial gyroscope). We extract the motion features and select a subset of features as a feature vector from the frequency domain of the sensing data using Fast Fourier Transform (FFT). We classify and predict human lower limb motion using three supervised learning algorithms: Naïve Bayes (NB), K-Nearest Neighbor (KNN), and Artificial Neural Networks (ANNs). We use 670 lower limb motion samples to train and verify these classifiers using the 10-folder cross-validation technique. Finally, we design and implement a live detection system to validate our motion detection approach. The experimental results show that our low-cost approach can recognize human lower limb activities with acceptable accuracy. On average, the recognition rate of NB, KNN, and ANNs are 97.01%, 96.12%, and 98.21%, respectively.


Assuntos
Smartphone , Dispositivos Eletrônicos Vestíveis , Algoritmos , Teorema de Bayes , Humanos , Extremidade Inferior , Movimento (Física)
18.
Front Nutr ; 9: 873657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694158

RESUMO

Oleaginous fungi (including fungus-like protists) are attractive in lipid production due to their short growth cycle, large biomass and high yield of lipids. Some typical oleaginous fungi including Galactomyces geotrichum, Thraustochytrids, Mortierella isabellina, and Mucor circinelloides, have been well studied for the ability to accumulate fatty acids with commercial application. Here, we review recent progress toward fermentation, extraction, of fungal fatty acids. To reduce cost of the fatty acids, fatty acid productions from raw materials were also summarized. Then, the synthesis mechanism of fatty acids was introduced. We also review recent studies of the metabolic engineering strategies have been developed as efficient tools in oleaginous fungi to overcome the biochemical limit and to improve production efficiency of the special fatty acids. It also can be predictable that metabolic engineering can further enhance biosynthesis of fatty acids and change the storage mode of fatty acids.

19.
RSC Adv ; 12(12): 7405-7412, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35424667

RESUMO

Three novel fluoranthene dyes were obtained by cycloaddition reactions using acrylonitrile and dialkyl acetylenedicarboxylates. Their fluorescence properties in different polar-organic solvents were investigated systematically. Meanwhile, spectral changes induced by the addition of water in methanol were observed, indicating that these fluoranthenes dyes can be efficiently used to detect the water content in methanol as probes. Significantly, the practical test measurements for the water contents in methanol illustrated the measured results with the three fluorescent probes were basically consistent with the water content added artificially. This demonstrated the potential of these fluoranthene dyes as probes in measuring the water content in methanol.

20.
Inorg Chem ; 61(13): 5388-5396, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35319197

RESUMO

A multifunctional metal-organic framework, (Hdmbpy)[Dy(H2dobdc)2(H2O)]·3H2O (Dy-MOF, H4dobdc = 2,5-dihydroxyterephthalic acid, dmbpy = 4,4'-dimethyl-2,2'-bipyridine), was synthesized and structurally characterized. The metal center DyIII is connected by four carboxyl groups to form the [Dy2(CO2)4] binuclear nodes, which are further interconnected by eight separate H2dobdc2- ligands to form a three-dimensional (3D) framework including hydrophilic triangular channels and abundant hydrogen-bonding networks. Dy-MOF has good stability in aqueous solution as well as in harsh acidic or alkaline solutions (pH range: 2.0-12.0). Furthermore, the luminescence signal of Dy-MOF undergoes a visualized color change as the acidity of the solution alters, which is the typical behavior of pH ratiometric probe. At a 100% relative humidity, Dy-MOF exhibits a high proton conductivity σ (1.70 × 10-4 S cm-1 at 303 K; 1.20 × 10-3 S cm-1 at 343 K) based on the proton hopping mechanism, which can be classified as a superionic conductor with σ exceeding 10-4 S cm-1. Additionally, the ferromagnetic interaction and magnetic relaxation behavior are simultaneously achieved in Dy-MOF. Herein, the combination of luminescence sensing, magnetism, and proton conduction in a single-phase 3D MOF may offer great potential applications in smart multitasking devices.

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