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1.
Ann Rheum Dis ; 83(6): 775-786, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38395605

RESUMO

OBJECTIVES: To systemically analyse the heterogeneity in the clinical manifestations and prognoses of patients with antisynthetase syndrome (ASS) and evaluate the transcriptional signatures related to different clinical phenotypes. METHODS: A total of 701 patients with ASS were retrospectively enrolled. The clinical presentation and prognosis were assessed in association with four anti-aminoacyl transfer RNA synthetase (ARS) antibodies: anti-Jo1, anti-PL7, anti-PL12 and anti-EJ. Unsupervised machine learning was performed for patient clustering independent of anti-ARS antibodies. Transcriptome sequencing was conducted in clustered ASS patients and healthy controls. RESULTS: Patients with four different anti-ARS antibody subtypes demonstrated no significant differences in the incidence of rapidly progressive interstitial lung disease (RP-ILD) or prognoses. Unsupervised machine learning, independent of anti-ARS specificity, identified three endotypes with distinct clinical features and outcomes. Endotype 1 (RP-ILD cluster, 23.7%) was characterised by a high incidence of RP-ILD and a high mortality rate. Endotype 2 (dermatomyositis (DM)-like cluster, 14.5%) corresponded to patients with DM-like skin and muscle symptoms with an intermediate prognosis. Endotype 3 (arthritis cluster, 61.8%) was characterised by arthritis and mechanic's hands, with a good prognosis. Transcriptome sequencing revealed that the different endotypes had distinct gene signatures and biological processes. CONCLUSIONS: Anti-ARS antibodies were not significant in stratifying ASS patients into subgroups with greater homogeneity in RP-ILD and prognoses. Novel ASS endotypes were identified independent of anti-ARS specificity and differed in clinical outcomes and transcriptional signatures, providing new insights into the pathogenesis of ASS.


Assuntos
Aminoacil-tRNA Sintetases , Autoanticorpos , Doenças Pulmonares Intersticiais , Miosite , Humanos , Miosite/imunologia , Miosite/genética , Feminino , Masculino , Prognóstico , Pessoa de Meia-Idade , Aminoacil-tRNA Sintetases/imunologia , Aminoacil-tRNA Sintetases/genética , Autoanticorpos/sangue , Autoanticorpos/imunologia , Doenças Pulmonares Intersticiais/imunologia , Doenças Pulmonares Intersticiais/genética , Adulto , Estudos Retrospectivos , Dermatomiosite/imunologia , Dermatomiosite/genética , Idoso , Fenótipo , Transcriptoma
2.
Artigo em Inglês | MEDLINE | ID: mdl-38648758

RESUMO

OBJECTIVES: To describe the longitudinal study and long-term prognosis of multicentre large inception cohort of patients with anti-SAE positive DM. METHODS: We retrospectively recruited patients with anti-SAE+DM in four tertiary referral centers from China between March 2005 and December 2022. Long-term survival analysis was performed in the enrolled patients. The Myositis Damage Index (MDI) and Cutaneous Disease Area and Severity Index (CDASI) were used to evaluate the degree of different organ damage and the extent of skin rashes. Longitudinal computed tomographic (CT) patterns were analyzed. Phenotypes were characterized using unsupervised cluster analysis. RESULTS: All-cause death occurred in 10.5% (4/38) of all patients, in which three patients succumbed to malignancies at 13, 18, and 36 months. Most patients had favorable long-term outcomes, 35.3% of them were in drug-free remission. Skin rashes showed significant improvement evaluated by CDASI with time. However, damage to different systems was observed in 70.6% of the surviving patients using the MDI, which mainly consisted in skin damage, accounting for 47.1%. Nine patients with anti-SAE+DM associated interstitial lung disease (ILD) underwent repeat CT showed marked radiological improvement at 6 months or being stable after 12 months. In further, different characteristics and outcomes were also showed in three clusters identified by unsupervised analysis. CONCLUSIONS: Anti-SAE+DM is characterized with lower mortality rate and the development of malignancies being the primary cause of death. Patients who survived showed notable cutaneous damage, while the ILD tends to stabilize. Clusters identified with unsupervised analysis could assist physicians in identifying higher risk of mortality.

3.
Opt Lett ; 49(8): 2197-2200, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621110

RESUMO

An all-solid fiber-tip Fabry-Perot interferometer (FPI) coated with a nickel film is proposed and experimentally verified for magnetic field sensing with high sensitivity. It is fabricated by splicing a segment of a thin-wall capillary tube to a standard single-mode fiber (SMF), then inserting a tiny segment of fiber with a smaller diameter into the capillary tube, and creating an ultra-narrow air-gap at the SMF end to form an FPI. When the device is exposed to magnetic field, the capillary tube is strained due to the magnetostrictive effect of the nickel film coated on its outer surface. In addition, owing to the unique breakpoint sensitivity-enhancement structure of the air-gap FPI, the elongation of the capillary tube whose length is over 100 times longer than the air-gap width is entirely transferred to the cavity length change of the FPI, and the sensor is extremely sensitive to the magnetic field as proved by our experiments, achieving a high sensitivity of up to 2.236 nm/mT for a linear magnetic field range from 40 to 60 mT, as well as a low-temperature cross-sensitivity of 56 µT/°C. The all-solid stable structure, compact size (total length of ∼3.0 mm), and reflective working mode with high magnetic field sensitivity indicate that this sensor has good application prospects.

4.
Opt Lett ; 48(9): 2229-2232, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126241

RESUMO

Electromagnetic topological edge states typically are created in photonic systems with crystalline symmetry and these states emerge because of the topological feature of bulk Bloch bands in momentum space according to the bulk-edge correspondence principle. In this work, we demonstrate the existence of chiral topological electromagnetic edge states in Penrose-tiled photonic quasicrystals made of magneto-optical materials, without relying on the concept of bulk Bloch bands in momentum space. Despite the absence of bulk Bloch bands, which naturally defiles the conventional definition of topological invariants in momentum space characterizing these states, such as the Chern number, we show that some bandgaps in these photonic quasicrystals still could host unidirectional topological electromagnetic edge states immune to backscattering in both cylinders-in-air and holes-in-slab configurations. Employing a real-space topological invariant based on the Bott index, our calculations reveal that the bandgaps hosting these chiral topological edge states possess a nontrivial Bott index of ±1, depending on the direction of the external magnetic field. Our work opens the door to the study of topological states in photonic quasicrystals.

5.
Chemistry ; 29(14): e202202744, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36446736

RESUMO

Among the factors that lead to the reduction of the efficiency of perovskite solar cells (PSCs) the difficulty involved in realizing a high-quality film and the efficient charge transfer that takes place at the interface between electron-transport layer (ETL) and perovskite is worth mentioning. Here, a strategy for planar-type devices by natural bio-functional interfaces that uses a buried electron-transport layer made of cobalamin complexed tin oxide (SnO2 @B12 ) is demonstrated. Having systematically investigated the effects of SnO2 @B12 interfacial layer in perovskite solar cells, it can be concluded that cobalamin can chemically link the SnO2 layer and the perovskite layer, resulting in improved perovskite film quality and interfacial defect passivation. Utilizing SnO2 @B12 improves the efficiency of planar-type PSCs by 20.60 %. Furthermore, after 250 h of exposure to an ambient atmosphere, unsealed PSCs containing SnO2 @B12 degrade by 10 %. This research provides a viable method for developing bio-functional molecules that will increase the effectiveness and durability of planar-perovskite solar cells.

6.
Sensors (Basel) ; 23(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37571597

RESUMO

A fiber speckle sensor (FSS) based on a tapered multimode fiber (TMMF) has been developed to measure liquid analyte refractive index (RI) in this work. By the lateral and axial offset of input light into TMMF, several high-order modes are excited in TMMF, and the speckle pattern is spatially modulated, which affects an asymmetrical speckle pattern with a random intensity distribution at the output of TMMF. When the TMMF is immersed in the liquid analyte with RI variation, it influences the guided modes, as well as the mode interference, in TMMF. A digital image correlations method with zero-mean normalized cross-correlation coefficient is explored to digitize the speckle image differences, analyzing the RI variation. It is found that the lateral- and axial-offsets-induced speckle sensor can enhance the RI sensitivity from 6.41 to 19.52 RIU-1 compared to the one without offset. The developed TMMF speckle sensor shows an RI resolution of 5.84 × 10-5 over a linear response range of 1.3164 to 1.3588 at 1550 nm. The experimental results indicate the FSS provides a simple, efficient, and economic approach to RI sensing, which exhibits an enormous potential in the image-based ocean-sensing application.

7.
J Asian Nat Prod Res ; 25(6): 564-570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929891

RESUMO

Two new sesquiterpenoids, named 9,10-dihydroxy-albaflavenone (1) and 5-hydroxy-albaflavenone (2) were isolated from Dictyophora indusiata. Their structures and absolute configurations were determined by NMR, ECD and HRESIMS. Compounds 1 and 2 showed anti-inflammatory activity by inhibiting TNF-α and NO secretion to varying degrees.


Assuntos
Basidiomycota , Sesquiterpenos , Basidiomycota/química , Sesquiterpenos/farmacologia , Fator de Necrose Tumoral alfa
8.
Molecules ; 28(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36985732

RESUMO

As an edible and medicinal fungus, Dictyophora indusiata is well-known for its morphological elegance, distinctive taste, high nutritional value, and therapeutic properties. In this study, eighteen compounds (1-18) were isolated and identified from the ethanolic extract of D. indusiata; four (1-4) were previously undescribed. Their molecular structures and absolute configurations were determined via a comprehensive analysis of spectroscopic data (1D/2D NMR, HRESIMS, ECD, and XRD). Seven isolated compounds were examined for their anti-inflammatory activities using an in vitro model of lipopolysaccharide (LPS)-simulated BV-2 microglial cells. Compound 3 displayed the strongest inhibitory effect on tumor necrosis factor-α (TNF-α) expression, with an IC50 value of 11.9 µM. Compound 16 exhibited the highest inhibitory activity on interleukin-6 (IL-6) production, with an IC50 value of 13.53 µM. Compound 17 showed the most potent anti-inflammatory capacity by inhibiting the LPS-induced generation of nitric oxide (NO) (IC50: 10.86 µM) and interleukin-1ß (IL-1ß) (IC50: 23.9 µM) and by significantly suppressing induced nitric oxide synthase (iNOS) and phosphorylated nuclear factor-kappa B inhibitor-α (p-IκB-α) expression at concentrations of 5 µM and 20 µM, respectively (p < 0.01). The modes of interactions between the isolated compounds and the target inflammation-related proteins were investigated in a preliminary molecular docking study. These results provided insight into the chemodiversity and potential anti-inflammatory activities of metabolites with small molecular weights in the mushroom D. indusiata.


Assuntos
Agaricales , Agaricales/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Simulação de Acoplamento Molecular , Anti-Inflamatórios/química , Óxido Nítrico/metabolismo
9.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364361

RESUMO

A topological index is a numerical parameter that is derived mathematically from a graph structure. In chemical graph theory, these indices are used to quantify the chemical properties of chemical compounds. We compute the first and second temperature, hyper temperature indices, the sum connectivity temperature index, the product connectivity temperature index, the reciprocal product connectivity temperature index and the F temperature index of a molecular graph silicate network and silicate chain network. Furthermore, a QSPR study of the key topological indices is provided, and it is demonstrated that these topological indices are substantially linked with the physicochemical features of COVID-19 medicines. This theoretical method to find the temperature indices may help chemists and others in the pharmaceutical industry forecast the properties of silicate networks and silicate chain networks before trying.


Assuntos
COVID-19 , Humanos , Temperatura , Silicatos
10.
Neurochem Res ; 46(11): 3050-3058, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34347266

RESUMO

Gut microbiota is closely related to the Parkinson's disease (PD) pathogenesis. Additionally, aggregation of α-synuclein (α-syn) is central to PD pathogenesis. Here we identified the further mechanisms of gut microbiota in PD. A mouse model with PD was established via injection of MPTP. Normal or MPTP-induced PD like animals were treated with FMT from healthy normal mice. Pole test and traction test were performed to examine the effects of FMT on motor function of PD mice. Fecal SCFAs were assessed by gas chromatography-mass spectrometry. The α-syn level in the substantia nigra pars compacta (SN) of mice was measured using western blot. Dopaminergic neurons and microglial activation in the SN were analyzed by immunohistochemistry (IHC) and immunofluorescence (IF) staining. FMT alleviated physical impairment, decreased fecal SCFAs in a mouse model of PD. Additionally, FMT decreased the expression of α-syn, as well as inhibited the activation of microglia in the SN, and blocked the TLR4/PI3K/AKT/NF-κB signaling in the SN and striatum. FMT could protect mice against PD via suppressing α-syn expression and inactivating the TLR4/PI3K/AKT/NF-κB signaling.


Assuntos
Transplante de Microbiota Fecal/métodos , NF-kappa B/antagonistas & inibidores , Transtornos Parkinsonianos/prevenção & controle , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , alfa-Sinucleína/antagonistas & inibidores , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neuroproteção/fisiologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 4 Toll-Like/metabolismo , alfa-Sinucleína/metabolismo
11.
Eur J Clin Microbiol Infect Dis ; 40(9): 1899-1907, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33837879

RESUMO

To explore the diagnostic value of a galactomannan (GM) detection for non-immunocompromised critically ill patients with influenza-associated aspergillosis (IAA). In this retrospective case-control study, we explored the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the receiver operating characteristic (ROC) curve (AUC) of serum and bronchoalveolar lavage fluid (BALF) GM tests by four detection strategies at different detection time points and with different compound modes. In total, 90 patients were evaluated. The AUC values of the second serum GM test, the first and second BALF GM tests, were significantly higher (0.839 (95% CI 0.716 to 0.963), P < 0.01; 0.904 (95% CI 0.820 to 0.988), P < 0.01; 0.827 (95% CI 0.694 to 0.961), P = 0.043) than that of the first serum GM test (0.548 (95% CI 0.377 to 0.718)). We found that at least one positive result on two consecutive serum GM tests (0.719 (95% CI 0.588 to 0.849)) was the best compared with the first positive test (0.419 (95% CI 0.342 to 0.641), P < 0.01) and positives on two consecutive tests (0.636 (95% CI 0.483 to 0.790), P = 0.014). However, there were no differences between those three detection strategies of BALF GM. The BALF GM test might have a better diagnostic value for IAA in the ICU than the serum GM test. A possible cutoff value of 1.0 to 1.3 was set for GM from BALF specimens for IAA. A single serum GM test is not routinely recommended, but at least one positive result on two consecutive tests appeared to be useful.


Assuntos
Aspergilose/diagnóstico , Líquido da Lavagem Broncoalveolar/química , Técnicas de Laboratório Clínico/estatística & dados numéricos , Galactose/análogos & derivados , Influenza Humana/complicações , Aspergilose Pulmonar Invasiva/diagnóstico , Mananas/análise , Adulto , Idoso , Estudos de Casos e Controles , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/normas , Estado Terminal , Feminino , Galactose/análise , Humanos , Influenza Humana/microbiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Estações do Ano , Sensibilidade e Especificidade
12.
Sensors (Basel) ; 21(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546145

RESUMO

A hollow biconical fiber is proposed and experimentally demonstrated for vibration sensing. It is fabricated by creating an air micro-cavity in single-mode fiber, followed by tapering it. Experimental results show that the device is highly sensitive to bending with a sensitivity of 21.30 dB/m-1. When it is exposed to vibration, its transmission loss is modulated periodically, then based on the measured transmission, the vibration frequency can be demodulated accurately. The acoustic vibration testing results show that the proposed device can detect and demodulate the exciting acoustic frequency accurately and distinguish its sound intensity, and the maximum signal to noise ratio (SNR) achieves up to 59 dB. Moreover, cantilever beam testing proves its performance reliable. Additionally, the sensing head has the advantages of a lightweight, compact size (with a total length of less than 250 µm), and insensitivity of temperature. All these features indicate the proposed sensor has a promising potential in the engineering field.

13.
Inorg Chem ; 57(21): 13653-13666, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30345765

RESUMO

Nanoparticles that possess unique structures and properties are highly desired in the production of multifunctional materials because of their combinational performance. In this study, a facile and effective fabricating strategy is developed to controllably prepare fluorescent hollow mesoporous silica nanorods via the cetyltrimethylammonium bromide (CTAB) and tetraphenylethene (TPE) luminogen-functionalized gemini surfactant (CTPE-C6-CTPE) guided dual-templating approach. Because of its unique chemical structure, water solubility, surface activity, and fluorescent properties, the designed CTPE-C6-CTPE will not only provide an anchored fluorophore for silica nanoparticles but also serve as an intimate partner of CTAB to regulate their construction in the structure-directing process. By properly tuning the molar ratio of CTAB/CTPE-C6-CTPE, the shape-controlled aggregation-induced emission hollow mesoporous silica nanoparticles (AIE-MSNs) can be prepared directly, producing two kinds of silica nanorods (AIE-MSNs-15 and AIE-MSNs-7). In particular, the incorporated bulky TPE luminogens will not only endow AIE-MSNs-7 with enhanced fluorescence intensity (2.3-fold) after the removal of CTAB but also bring about high accessible surface area (606.6 m2/g) and larger pore size (3.2 nm) and pore volume (0.634 cm3/g) for effective loading and sustained release of the hydrophobic anticancer drug camptothecin. CTPE-C6-CTPE enriches the family of gemini surfactants and provides important insights into the convenient fabrication of advanced fluorescent mesoporous materials.

14.
RMD Open ; 10(2)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580342

RESUMO

AIM: We aimed to explore a new and readily available practical marker for rapidly progressive interstitial lung disease (RP-ILD) and poor short-term outcomes in patients with idiopathic inflammatory myopathies (IIM). METHODS: A total of 1822 consecutive patients with IIM between 2009 and 2021 were evaluated retrospectively. All proven cases of naïve ILD with complete medical records were included. Red cell distribution width (RDW) values at the initial stage, 3 months and last follow-up were collected. The clinical characteristics and outcomes of the patients were recorded. RESULTS: We identified 532 patients with IIM with an average follow-up of 4 years. ILD prevalence was higher in patients of elevated RDW (p<0.001). The patients with ILD and elevated RDW had lower levels of PaO2/FiO2, FVC% and DLco% and a higher prevalence of RP-ILD than those with normal RDW (p<0.001). Prognostic analysis revealed that RDW was an independent risk factor for prognosis in patients with IIM-ILD (HR=2.9, p=0.03). Patients with dermatomyositis (DM) with RP-ILD with a change in RDW within 3 months (∆RDW-3) greater than 0 were more likely to die within 3 months. Moreover, the prevalence of ∆RDW-3>0 was higher in patients with RP-ILD and positive for anti-melanoma differentiation-associated gene 5 antibody who died within 3 months (87.5%) compared with those alive at 3 months (24.6%) (p<0.001). CONCLUSION: These findings suggest that repeated RDW assays could assist physicians in identifying patients with DM-ILD who were at a high risk of RP-ILD and death.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Miosite , Humanos , Dermatomiosite/complicações , Dermatomiosite/diagnóstico , Dermatomiosite/epidemiologia , Estudos Retrospectivos , Índices de Eritrócitos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/etiologia , Miosite/complicações
15.
Huan Jing Ke Xue ; 45(7): 3965-3972, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022944

RESUMO

The aim of this study was to comprehensively understand the water environment quality status and its change trend in the Inner Mongolia section of the Yellow River Basin. To analyze the water quality in recent years,the water quality data in the Yellow River basin from 2003 to 2020 were firstly collected from five typical monitoring stations.Various data analysis methods, including principal component analysis, cluster analysis, and a long short-term memory model, were used along with an improved comprehensive water quality identification index to explore the spatiotemporal characteristics of water quality in the Yellow River Basin. The results showed that the overall water quality in the basin has improved and stabilized over time. In terms of temporal variation, there was a distinction between the wet season and dry season, with a better status observed during the wet season due to increased agricultural irrigation and higher water volume. Spatially, the five monitoring sections could be divided into three categories based on strong natural factors that maintained their temporal characteristics during the wet season; however, significant differences were observed during the dry season due to urban water usage patterns. Analysis using LSTM models revealed that ammonia nitrogen will continue to decline and have a decreasing impact on the comprehensive water quality. These findings provide valuable insights for the comprehensive management of water quality in Inner Mongolia's Yellow River Basin.

16.
Immunotherapy ; 15(1): 27-33, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36617958

RESUMO

Primary submandibular gland tumors are relatively rare. Due to its low incidence and broad spectrum phenotypic, biological and clinical heterogeneity types, a wide range of options have been developed to treat this tumor. To date, however, efficacious standard treatment regimens are lacking. Here, the authors present a case of a patient with an advanced submandibular gland tumor. Histological and imaging results diagnosed the case as stage IV submandibular gland adenocarcinoma with multiple metastases. The patient was subjected to systemic platinum-based chemotherapy combined with sintilimab. A primary lesion complete response was observed after six cycles of treatment. This case affirms the efficacy of the PD-1 inhibitor sintilimab combined with platinum-based chemotherapy as a first-line treatment for advanced submandibular gland tumors.


Primary submandibular gland tumors are very uncommon. There is a lack of standard treatment plans due to the low incidence and diverse clinical situations. The authors report a case of an advanced submandibular gland tumor patient who received platinum-based chemotherapy combined with sintilimab as the initial treatment plan. The tumor and multiple lung metastases significantly shrank after six cycles of treatment. This case indicates the regimen is effective for advanced submandibular gland tumor patients.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Submandibular , Humanos , Neoplasias da Glândula Submandibular/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Inibidores de Checkpoint Imunológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
17.
J Agric Food Chem ; 70(18): 5728-5737, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35475366

RESUMO

All O-methylated derivatives of emodin, including physcion, questin, and 1-O-methylemodin, show potential antifungal activities. Notably, emodin and questin are two pivotal intermediates of geodin biosynthesis in Aspergillus terreus. Although most of the geodin biosynthetic steps have been investigated, the key O-methyltransferase (OMT) responsible for the O-methylation of emodin to generate questin has remained unidentified. Herein, through phylogenetic tree analysis and in vitro biochemical assays, the long-sought class II emodin-O-methyltransferase GedA has been functionally characterized. Additionally, the catalytic mechanism and key residues at the catalytic site of GedA were elucidated by enzyme-substrate-methyl donor analogue ternary complex crystal structure determination and site-directed mutagenesis. As we demonstrate, GedA adopts a typical general acid/base (E446/H373)-mediated transmethylation mechanism. In particular, residue D374 is also crucial for efficient catalysis through blocking the formation of intramolecular hydrogen bonds in emodin. This study will facilitate future engineering of GedA for the production of physcion or other site-specific O-methylated anthraquinone derivatives with potential applications as biopesticides.


Assuntos
Emodina , Aspergillus/genética , Metiltransferases/química , Metiltransferases/genética , Filogenia
18.
Food Chem ; 394: 133536, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35753253

RESUMO

Herein, a molecularly imprinted surface-enhanced Raman spectroscopy (SERS) sensor was developed for the selective capture and sensitive detection of tryptamine in foods. The SERS sensor exploited silver nanoparticle-decorated TiO2 (TiO2@Ag) substrates for Raman signal enhancement via synergistic effect of electromagnetic enhancement and photoinduced charge-transfer, whilst surface functionalization with the molecularly imprinted polymer ensured selective tryptamine capture. The SERS spectrum of tryptamine on the sensor closely matched that predicted by density functional simulations. The SERS intensity for tryptamine on the developed TiO2@Ag@MIP sensor increased linearly with the logarithm of the tryptamine concentration over the range of 10-6-10-2 mol L-1, with a LOD of 4.85 × 10-7 mol L-1. Tryptamine was detected in a spiked white vinegar sample, and its recoveries were in the range of 92.00%-111.40%. The SERS sensor could be used for the detection of tryptamine in actual samples.


Assuntos
Nanopartículas Metálicas , Prata , Limite de Detecção , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos , Titânio , Triptaminas
19.
Nat Prod Res ; 35(19): 3241-3247, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31741411

RESUMO

Seven lignans and eight phenylpropanoids, including one new lignan, 7S,8R,8'R-5,5'-dimethoxyariciresinol-4-O-ß-D-glucopyranoside (1), were isolated from the liquid juice of Phyllostachys edulis. Their structures were established by extensive spectroscopic analyses. The absolute configuration of the new compound was determined by comparing its experimental electronic circular dichroism (ECD) spectra with calculated ECD spectra. All compounds were evaluated for their anti-inflammatory activity and xanthine oxidase inhibitor activity, and the results showed that compound 9 exhibited a moderate activity in these two bioassays. In addition, all the compounds can be detected in health panda faeces by LC-MS.


Assuntos
Lignanas , Poaceae/química , Propionatos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Dicroísmo Circular , Fezes/química , Lignanas/isolamento & purificação , Lignanas/farmacologia , Espectrometria de Massas , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Propionatos/isolamento & purificação , Ursidae , Xantina Oxidase/antagonistas & inibidores
20.
Sci Rep ; 10(1): 19664, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184510

RESUMO

Bamboo juice is a traditional Chinese drink and herbal medicine, and bamboo juice oral liquids are widely sold for the treatment of cough and phlegm in China. In this study, 26 main compounds of bamboo juice (Phyllostachys edulis) were separated, precisely identified, and qualitative analysis using NMR (nuclear magnetic resonance) and quantitative analysis using UPLC-Q-TOF-MS (ultra-performance liquid chromatography with high-resolution quadrupole time-of-flight mass spectrometer), respectively. Potentially harmful levels of added excessive preservatives, including benzoic acid, ethylparaben, and sorbic acid, were found in bamboo juice oral liquid. Carbohydrates were determined to be the major components of bamboo juice, with contents as high as 191.13 g L-1, far higher than those of other compounds. The result indicated that the cough relief activity of bamboo juice oral liquid may be related to their high levels of added preservatives.


Assuntos
Medicamentos de Ervas Chinesas/química , Poaceae/química , Antitussígenos/química , Carboidratos/análise , Cromatografia Líquida , Conservantes de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Plantas Medicinais/química
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