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1.
Biomed Chromatogr ; : e5255, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34612532

RESUMO

The allergic reaction (AR) of Chinese herbal injection has become one of the most noticeable focuses of public health in China. However, it still has been remained considerable controversial whether low-molecular-weight components in Chinese herbal injection have potential sensitization. In this study, the relationship between AR and low-molecular-weight component profile of Shenmai injection was explored by an interdisciplinary technology integrating real-world evidence and ultra performance liquid chromatography-quadrupole time-of-flight mass spectroscopy (UPLC-Q-TOF-MS). The AR information of hospitalized patients was obtained by comprehensive analyzing real-world evidence from January 2015 to June 2019 at two Chinese hospitals. The UPLC-Q-TOF-MS was exploited to systematically investigate the low-molecular-weight component profile with 50-1500 m/z mass range and 3,725 MS1 peaks were detected. The optimized partial least squares discriminant analysis model was established to map the influence of low-molecular-weight components on AR. The results of this study showed that high levels of organic acids might be potential risk factor for inducing AR administered intravenously. By using the method, Shenmai injection with high AR risk could be recognized precisely with 100% accuracy before clinical use.

2.
Bioorg Med Chem Lett ; : 128413, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34634473

RESUMO

In this present study, a series of novel (E)-2-benzylidene-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)hydrazine-1-carboxamide derivatives against α-glucosidase were designed and synthesized, and their biological activities were evaluated in vitro and in vivo. Most of the designed analogues exhibited better inhibitory activity than the marketed acarbose, especially the most potent compound 7 with an IC50 value of 9.26 ± 1.84 µM. The direct binding of 7 and 8 with α-glucosidase was confirmed by fluorescence quenching experiments, and the kinetic and molecular docking studies revealed that 7 and 8 inhibited α-glucosidase in a non-competitive manner. Cytotoxicity bioassay indicated compounds 7 and 8 were non-toxic towards LO2 and HepG2 at 100 µM. Furthermore, both compounds were demonstrated to have in vivo hypoglycemic activity by reducing the blood glucose levels in sucrose-treated rats.

3.
Appl Environ Microbiol ; : AEM0153421, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586909

RESUMO

Biological foaming (or biofoaming) is a frequently occurring problem in wastewater treatment plants (WWTPs) and is attributed to the overwhelming growth of filamentous bulking and foaming bacteria (BFB). Biological foaming has been intensively investigated, with BFB like Microthrix and Skermania having been identified from WWTPs and implicated in foaming. Nevertheless, studies are still needed to improve our understanding of the microbial diversity of WWTPs biofoams and how microbial activities contribute to foaming. In this study, sludge foaming at the Qinghe WWTP of China was monitored, and sludge foams were investigated using culture-dependent and culture-independent microbiological methods. The foam microbiomes exhibited high abundances of Skermania, Mycobacterium, Flavobacteriales, and Kaistella. A previously unknown bacterium, Candidatus Kaistella beijingensis, was cultivated from foams, its genome sequenced, and it was phenotypically characterized. Ca. K. beijingensis exhibits hydrophobic cell surfaces, produces extracellular polymeric substances (EPS), and metabolizes lipids. Ca. K. beijingensis abundances were proportional to EPS levels in foams. Several proteins encoded by the Ca. K. beijingensis genome were identified from EPS that was extracted from sludge foams. Ca. K. beijingensis populations accounted for 4-6% of the total bacterial populations in sludge foam samples within the Qinghe WWTP, although their abundances were higher in spring than in other seasons. Co-occurrence analysis indicated that Ca. K. beijingensis was not a core node among the WWTP community network, but its abundances were negatively correlated with those of the well-studied BFB Skermania piniformis among cross-season Qinghe WWTP communities. Importance Biological foaming or scumming is a sludge separation problem that has become the subject of major concern for long-term stable activated sludge operation in decades. Biological foaming was considered induced by foaming bacteria. However, the occurrence and deterioration of foaming in many WWTPs are still not completely understood. Cultivation and characterization of the enriched bacteria in foaming are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the understanding of their relationships with foaming and performance of WWTPs.

4.
J Mol Model ; 27(10): 307, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591190

RESUMO

Due to the diversity of solid nitrogen structure, its phase transition has been a hot topic for many scientists. Herein, we first studied the structural softening of rhombohedral solid nitrogen under pressure using first-principles calculations. Then, a new criterion, Egret criterion, was proposed to predict the whole process from beginning to end of structural phase transition of solid nitrogen. Based on the discussion of acoustic phonons, we concluded that the phase transition of rhombohedral solid nitrogen starts from k-point F along the [- 1, - 1, 0] direction in a-axis, and the structural phase transition velocity is slow. Also, we use the Egret criterion proposed by us to predict the emergence of ξ-N2 and the stability of ξ-N2 at 17 GPa and 22 GPa, respectively, and this result is in good agreement with the phase diagram of nitrogen.

5.
Adv Sci (Weinh) ; : e2102666, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523247

RESUMO

Necrosis induces strong inflammation with undesirable implications in clinics compared with apoptosis. Fortunately, the switch between necrosis and apoptosis could be realized by tailoring the appropriate structural properties of gold nano rods (GNRs) that could precisely modulate cell death pathways. Herein, the intracellular interaction between GNRs and organelles is monitored and it is found that lysosomes dominates necrosis/apoptosis evoking. Then the surface molecule density of GNRs, which is first defined as ρsurf. molecule (Nsurf. molecules /(a × π × Diameter × Length)), mediates lysosome activities as the membrane permeabilization (LMP), the Cathepsin B and D release, the cross-talk between lysosome and different organelles, which selectively evokes apoptosis or necrosis and the production of TNF-α from macrophages. GNRs with small ρsurf. molecule mainly induce apoptosis, while with large ρsurf. molecule they greatly contribute to necrosis. Interestingly, necrosis can be suppressed by GNRs with higher ρsurf. molecule due to the overexpression of key protease caspase 8, which cleaves the RIP1-RIP3 complex and activates caspase 3 followed by necrosis to apoptosis transition. This investigation indicates that the ρsurf. molecule greatly affects the utility of nanomaterials and different structural properties of nanomaterials have different implications in clinics.

6.
Appl Microbiol Biotechnol ; 105(19): 7517-7528, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34519857

RESUMO

Aquatic and wetland systems are widely used for landscapes and water regeneration. Microbiomes and submerged macrophytes (hydrophytes) play essential roles in conversions of organic and inorganic compounds in those ecosystems. The systems were extensively investigated for microbial diversities and compositions. However, little is known about how hydrophytes recruited diverse microbiota and affected functional zonation in aquatic systems. To address this issue, epiphytic leaf and root, sediment, and surrounding water samples were collected from the dragon-shape aquatic system in Beijing Olympic Park. Metagenomic DNAs were extracted and subjected to sequencing. Results showed that epiphytic leaf and root microbiomes and metabolic marker genes were remarkably different from that of surrounding environment. Twenty indicator bacterial genera for epiphytic microbiomes were identified and 50 metabolic marker genes were applied to evaluate the function of epiphytic leaf and root, water, and sediment microbiomes. Co-occurrence analysis revealed highly modularized pattern of metabolic marker genes and indicator bacterial genera related to metabolic functions. These results suggested that hydrophytes shaped microbiomes and drove functional zonation in aquatic systems. KEY POINTS: • Microbiomes of hydrophytes and their surrounding environments were investigated. • Twenty indicator bacterial genera highly specific to epiphytic biofilms were identified. • Epiphytes recruited unique microbiomes and drove functional zonation in aquatic systems.


Assuntos
Metagenômica , Microbiota , Pequim
7.
J Hazard Mater ; 424(Pt A): 127296, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34592593

RESUMO

In order to produce safe rice from cadmium (Cd) contaminated soils, a special pot experiment in the field was proposed to facilitate the study of multiple remediation measures. In the field experiments, four treatments were selected for the first half of the year: rice without soil treatment (R); rice with zeolite stabilization (RZ); oilseed rape phytoremediation (OR); and inter-cropping Sedum alfredii and maize phytoremediation (IC). As the early rice with zeolite stabilization still contained elevated Cd, manganese (Mn) fertilizer was added in the late rice with a special pot experiment in the field. Results showed that, in the first crops, the grains of maize and oilseed rape contained Cd below the food standard limit, while Cd in rice grain exceeded the limit of 0.2 mg/kg. The RZ treatment did not reduce Cd in rice but decreased significantly Mn in rice straw. In the late rice, Mn fertilizer additionally reduced Cd in rice grain to 0.12 mg/kg in combination with the RZ treatment. Mn accumulation in rice straw was enhanced by Mn fertilizer. These results indicate that the pot experiment in the field provides a useful tool to further evaluate effective treatment combinations to reduce Cd in rice.

8.
Adv Mater ; : e2105002, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561905

RESUMO

The precise tuning and multi-dimensional processing of covalent organic frameworks (COFs)-based materials into multicomponent superstructures with appropriate diversity are essential to maximize their advantages in catalytic reactions. However, up to now, it remains an ongoing challenge for the precise design of COFs-based multicomponent nanocomposites with diverse architectures. Herein, a metal organic framework (MOF)-sacrificed in situ acid-etching (MSISAE) strategy that enables continuous synthesis of core-shell, yolk-shell, and hollow-sphere COFs-based nanocomposites through tuning of core decomposition (NH2 -MIL-125 into TiO2 ) rate is developed. More importantly, due to the multiple active sites, fast transfer of carriers, increased light utilization ability, et al, one of the obtained samples, NH2 -MIL-125/TiO2 @COF-366-Ni-OH-HAc (yolk-shell) with special three components, exhibits high photocatalytic CO2 -to-CO conversion efficiency in the gas-solid mode. The MSISAE strategy developed in this work achieves the precise morphology design and control of multicomponent hybrid composites based on COFs, which may pave a new way in devealoping porous crystalline materials with powerful superstructures for multifunctional catalytic reactions.

9.
J Hazard Mater ; 416: 126236, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492988

RESUMO

In this work, a well-known Au25 NCs with high purity was prepared by simple one-pot reducing method. The as-synthesized Au25 NCs exhibited excellent antibacterial efficiency toward Gram-negative bacteria in a dose- and time-dependent manner, which could be used as nanoantibiotics to replace harmful antibiotics. The antibacterial assays showed that almost 100% bacteria were killed at lower concentration (100-150 µM) within a short time (30-60 min), providing a rapid and effective killing outcome for Gram-negative bacteria. After that, antibacterial mechanism was mainly investigated at cellular level via destruction of membrane integrity, disruption of antioxidant defense system, metabolic inactivation, DNA damage, as well as at molecular level via transcriptome analysis (RNA sequencing) for the first time. RNA sequencing results showed that differentially expressed genes (DEGs) related to biosynthesis of cell wall and membrane, glycolysis and TCA cycle, oxidative phosphorylation and DNA replication and repair were significantly affected. It was concluded that synergetic effect of membrane damage, oxidative stress, DNA damage and energy metabolism eventually led to the Gram-negative bacteria growth inhibition and death.


Assuntos
Anti-Infecciosos , Ouro , Antibacterianos/farmacologia , Perfilação da Expressão Gênica , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana
10.
Int J Stroke ; : 17474930211051531, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34569886

RESUMO

Background Approximately 1/3 of spontaneous intracerebral hemorrhage (sICH) patients did not know the onset time and were excluded from studies about time-dependent treatments for hyperacute sICH. Aims To help clinicians explore the benefit of time-dependent treatments for unclear-onset patients, we presented artificial intelligence models to identify onset time using non-contrast computed tomography (NCCT) based on weakly supervised multitask learning (WS-MTL) structure. Methods The patients with reliable symptom onset time (strong label) or repeat CT (weak label) were included and split into training set and test set (internal and external). The WS-MTL structure utilized strong and weak labels simultaneously to improve performance. The models included three binary classification models for classifying whether NCCT acquired within 6, 8 or 12 hours for different treatments measured by area under curve (AUC), and a regression model for determining the exact onset time measured by mean absolute error (MAE). The generalizability of models was also explored in comprehensive analysis. Results 4 004 patients with 10 780 NCCT scans were included. The performance of WS-MTL classification model showed high accuracy, and that of regression model was satisfactory in ⤠6 hours subgroup. In comprehensive analysis, the WS-MTL showed better performance for larger hematomas and thinner scans. And the performance improved effectively as training amounts increasing and could be improved steadily through retraining. Conclusions The WS-MTL models showed good performance and generalizability. Considering the large number of unclear-onset sICH patients, it may be worth to integrate the WS-MTL model into clinical practice to identify the onset time.

11.
Anticancer Drugs ; 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34486539

RESUMO

Leptomeningeal metastasis (LM) is one of the most serious complications of non-small cell lung cancer (NSCLC) without standard treatment guidelines and is always accompanied by poor prognosis. Identifying the types of gene mutations is essential to improve the outcome, and an increasing number of rare epidermal growth factor receptor (EGFR) mutations are revealed by next-generation sequencing (NGS). Here, we describe a case of a 56-year-old man who was diagnosed with lung adenocarcinoma and received thoracoscopic resection in May 2015. One year later, LM was confirmed by positive cerebrospinal fluid cytology. Given the existence of EGFR exon 19 deletions, erlotinib was implemented and achieved a short response for 10 months. Then the systemic therapy was changed to osimertinib and obtained clinical remission for 25 months. Owing to the resurgence of violent headache, retching and vomiting, NGS of cerebrospinal fluid was performed and two rare EGFR-SEPT14 fusions were found. Osimertinib combined bevacizumab, chemotherapy (carboplatin and abraxane) and dacomitinib were implemented in turn but ineffective. Thus, osimertinib combined intrathecal chemotherapy with pemetrexed were carried out and gained a complete remission of neurologic symptoms, stable lesions and long-term survival without notable side effects. This study presented the first case of NSCLC-LM harboring particular EGFR-SEPT14 fusions, who showed a durable response to osimertinib and intrathecal pemetrexed, providing a potential therapeutic option for NSCLC-LM patients with this particular mutation.

12.
Bioorg Chem ; 115: 105236, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34411978

RESUMO

α-Glucosidase inhibitors, which can inhibit the digestion of carbohydrates into glucose, are one of important groups of anti-type 2 diabetic drugs. In the present study, we report our effort on the discovery and optimization of α-glucosidase inhibitors with tetrahydrobenzo[b]thiophen-2-yl)urea core. Screening of an in-house library revealed a moderated α-glucosidase inhibitors, 5a, and then the following structural optimization was performed to obtain more efficient derivatives. Most of these derivatives showed increased inhibitory activity against α-glucosidase than the parental compound 5a (IC50 of 26.71 ± 1.80 µM) and the positive control acarbose (IC50 of 258.53 ± 1.27 µM). Among them, compounds 8r (IC50 = 0.59 ± 0.02 µM) and 8s (IC50 = 0.65 ± 0.03 µM) were the most potent inhibitors, and showed selectivity over α-amylase. The direct binding of both compounds with α-glucosidase was confirmed by fluorescence quenching experiments. Kinetics study revealed that these compounds were non-competitive inhibitors, which was consistent with the molecular docking results that compounds 8r and 8s showed high preference to bind to the allosteric site instead of the active site of α-glucosidase. In addition, compounds 8r and 8s were not toxic (IC50 > 100 µM) towards LO2 and HepG2 cells. Finally, the in vivo anti-hyperglycaemic activity assay results indicated that compounds 8r could significantly decrease the level of plasma glucose and improve glucose tolerance in SD rats treated with sucrose. The present study provided the tetrahydrobenzo[b]thiophen-2-yl)urea chemotype for developing novel α-glucosidase inhibitors against type 2 diabetes.

13.
Phytomedicine ; 91: 153665, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34403878

RESUMO

BACKGROUND: Studies revealed that particulate matter 2.5 (PM2.5) enters the lung through the respiratory tract and can damage lung tissue resulting in lung injury primarily via imbalance between pro-inflammatory and anti-inflammatory responses. Moreover, TLR4/NF-κB signaling pathways are reported to play a role in PM2.5-induced inflammation and lung injury, which is closely related to the inflammatory responses. Therefore, the traditional herbal formula, Deng-Shi-Qing-Mai-Tang (DSQMT), has been applied to improve patients' clinical symptoms with lung injury induced by PM2.5. It can reduce inflammatory reactions in lung injury and relieve cough and phlegm. However, the underlying mechanism of DSQMT treatment is still exclusive. PURPOSE: To clarify the preventive and therapeutic effects of DSQMT on PM2.5-induced lung injury and explore its underlying mechanism. STUDY DESIGN: PM2.5-induced lung injury rat model was established, and DSQMT was administered. METHODS: First, PM2.5 was collected, and PM2.5 suspension was prepared. Then, a rat model with PM2.5-induced lung injury was established, and the effects of DSQMT were evaluated in vivo. Finally, the roles of DSQMT in inhibiting the TLR4/NF-κB signaling pathway were investigated in vitro using the NR8383 cell line via Western blot analysis, real-time PCR, electrophoretic mobility shift assay (EMSA), and immunofluorescence staining, respectively and analyzed. RESULTS: We found that DSQMT significantly attenuated pathological lung tissue damage and inflammatory responses in PM2.5-induced lung injury. We also found that after PM2.5 stimulation in vitro, DSQMT regulates the expression of TLR4, MyD88, IKK, IκB-α, NF-κB p65 in the TLR4/NF-κB signaling pathway. It also constrains activated NF-κB entry into the nucleus and further limits its binding to target DNA. In addition, we revealed that DSQMT down-regulated interleukin (IL)-1ß, IL-6, IL-10, THF-α, NO, PGE2 to reduce the inflammatory response. CONCLUSION: We demonstrated that DSQMT has preventive and therapeutic effects on PM2.5-induced lung injury by down-regulation of the TLR4/NF-κB signaling pathway. Therefore, the efficacy of traditional Chinese medicine (TCM) in PM2.5 lung injury can be taken into consideration and may be improved in the future through further researches.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Lesão Pulmonar , NF-kappa B , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , NF-kappa B/metabolismo , Material Particulado/toxicidade , Ratos , Receptor 4 Toll-Like/metabolismo
14.
Bioorg Med Chem ; 46: 116352, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34403955

RESUMO

Aldehyde dehydrogenase 1A1 (ALDH1A1) plays vital physiological and toxicological functions in many areas, such as CNS, inflammation, metabolic disorders, and cancers. Overexpression of ALDH1A1 has been disclosed to play an important role in obesity, diabetes and other diseases, indicating the potential need for the identification and development of small molecule ALDH1A1 inhibitors. Herein, a series of benzimidazole derivatives was designed, synthesized and evaluated. Among them, compounds 21, 27, 29, 61 and 65 exhibited excellent inhibitory activity against ALDH1A1 with IC50 values in the low micromolar range and high selectivity over ALDH1A2, ALDH1A3, ALDH2 and ALDH3A1. Moreover, an in vitro study demonstrated that all five compounds effectively improved glucose consumption in HepG2 cells, of which, 61 and 65 at 10 µM produced nearly equal glucose consumption with positive control Metformin (Met) at 1 mM. Furthermore, 61 and 65 showed desirable metabolic stability in human liver microsomes. All these results suggest that 61 and 65 are suitable for further studies.

15.
Front Public Health ; 9: 695192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368062

RESUMO

Limited studies have focused on the impact of ambient air pollution on spina bifida. A population-based case-control study was conducted in Liaoning Province, China to assess the associations between maternal PM10 exposures in various exposure windows and spina bifida risk. Data on spina bifida cases born between 2010 and 2015 were available from the Maternal and Child Health Certificate Registry of Liaoning Province. Controls were a random sample of healthy livebirths without any birth defects delivered in the selected five cities during 2010-2015. Ambient air monitoring data for PM10 were obtained from 75 monitoring stations in Liaoning Province. The multivariable logistic regression models were established to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI). We further performed sensitivity analyses by using three propensity score methods. A total of 749 spina bifida cases and 7,950 controls were included. After adjusting for potential confounders, spina bifida was associated with a 10 µg/m3 increment in PM10 during the first trimester of pregnancy (adjusted OR = 1.06, 95% CI: 1.00-1.12) and the 3 months before pregnancy (adjusted OR = 1.12, 95% CI: 1.06-1.19). The adjusted ORs in the final model for the highest vs. the lowest quartile were 1.51 (95% CI: 1.04-2.19) for PM10 during the first trimester of pregnancy and 2.01 (95% CI: 1.43-2.81) for PM10 during the 3 months before pregnancy. Positive associations were found between PM10 exposures during the single month exposure windows and spina bifida. Sensitivity analyses based on two propensity score methods largely reported similar positive associations. Our findings support the evidence that maternal PM10 exposure increases the risk of spina bifida in offspring. Further, validation with a prospective design and a more accurate exposure assessment is warranted.


Assuntos
Poluição do Ar , Disrafismo Espinal , Poluição do Ar/efeitos adversos , Estudos de Casos e Controles , Criança , Feminino , Humanos , Material Particulado/efeitos adversos , Gravidez , Estudos Prospectivos , Disrafismo Espinal/induzido quimicamente
16.
Artigo em Inglês | MEDLINE | ID: mdl-34382925

RESUMO

A novel Gram-stain-negative strain, WQ 117T, isolated from the faeces of Rhinopithecus bieti collected at Yunnan Snub-nosed Monkey National Park, Yunnan province, PR China, was subjected to a polyphasic taxonomic study. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate represented a member of the genus Faecalibacter, sharing 97.64 % sequence similarity with the type strain Faecalibacter macacae YIM 102668T. The G+C content of the genomic DNA of WQ117T was 30.5 mol%. The predominant isoprenoid quinone was MK-6. The major cellular fatty acids was iso-C15 : 0. The whole genome average nucleotide identity (gANI) values and the digital DNA-DNA hybridization values between WQ 117T and YIM 102668T were 79.66 % and 22.20 %, respectively. Growth occurred at 0-50 °C (optimally at 28-35 °C), pH 7.0-9.0 (optimally at pH 8.0) and with 0-2 % (w/v) NaCl (optimally without NaCl). On the basis of the taxonomic evidence, a novel species, Faecalibacter rhinopitheci sp. nov., is proposed. The type strain is WQ 117T (=KCTC 82394T=CCTCC AA 2020027T).


Assuntos
Bacteroidetes/classificação , Filogenia , Presbytini , Animais , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Presbytini/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
J Nat Med ; 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34417964

RESUMO

One new compound, crocusatin M (1), and three new glycosidic compounds, crocusatins N-P (2-4), along with nine known compounds were isolated from the dried stigmas of Crocus sativus. The structures of new compounds were elucidated on the basis of spectroscopic analysis, and the absolute configurations of 1, 2, and 3 were unambiguously assigned by the comparison of experimental and calculated ECD data. This is the first report of the isolation of 4 with the HMG moiety from the genus Crocus. Compounds 1 and 4 exhibited weak anti-inflammatory activities on inhibiting lipopolysaccharide (LPS)-induced NO production.

18.
J Ethnopharmacol ; : 114578, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34464702

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Canarium album Raeusch. belongs to the Burseraceae family. Its ripe fruits, known as Qing Guo (QG) in Traditional Chinese Medicine (TCM), are used to treat sore throat, cough, and fish or crab poisoning. QG was reported to have antibacterial activity, and it exerted excellent anti-Helicobacter pylori (H. pylori) activity in our screening of abundant TCM. However, few studies have reported its anti-H. pylori activity and mechanism. AIM OF STUDY: The commonly used eradication therapies for H. pylori infection are antibiotic-based therapies. With the increasing antibiotic resistance of H. pylori, interest in finding alternative therapies has been aroused. This study investigated the phytochemistry profile, in vitro anti-H. pylori activity and possible anti-bacterial mechanism of QG extracts. MATERIALS AND METHODS: QG extracts were obtained by heat reflux extraction, microwave extraction or liquid-liquid extraction with different solvents. The quantitative and qualitative phytochemical analyses were performed by colorimetric determination, high-performance liquid chromatography (HPLC), and UPLC-electrospray ionization mass spectrometry (ESI-MS). In vitro anti- H. pylori activity was assessed by broth micro-dilution method. Mechanism of action studies included morphological observation using electron microscopy, urease inhibition assay and determination of expression of virulence genes by RT-qPCR. RESULTS: All QG extracts especially ethyl acetate extract (QGEAE) were rich in phenolic components, with the minimum inhibitory concentrations (MICs) on H. pylori of 39-625 µg/ml and minimum bactericidal concentrations (MBCs) of 78-1250 µg/ml. Both aqueous extract (QGAE) and QGEAE could induce the morphological and structural changes of H. pylori, inhibit urease activity with IC50 of 1093 µg/ml and 332.90 µg/ml, respectively, and down-regulate the virulence genes, such as vacA and cagA. CONCLUSIONS: QG may exhibit in vitro anti-H. pylori activity by inhibiting growth, destroying the bacterial structure and down-regulating the expression of virulence factors. Moreover, QG is the homology of food and TCM, which can be considered as a safe and convenient agent against H. pylori infection.

19.
Luminescence ; 36(7): 1761-1766, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34250703

RESUMO

A new rhodol-derived fluorescent probe 1 with picolinate as the recognition receptor was designed and simply synthesized using a one-step reaction. With the concentration of added Cu2+ increases, it gradually turns pink, so the effect of naked eye detection can be achieved. The detection limit of probe 1 for Cu2+ is 42 nM, and the linear detection range was 0-2 µM. The experimental results showed that 1 was a fluorescent probe with high selectivity, good water solubility, and high sensitivity to Cu2+ . Probe 1 was successfully applied in cell imaging experiments and can detect the concentration of Cu2+ in water samples. All these indicate that probe 1 has the potential to be applied to the detection of Cu2+ concentration in the real environment.


Assuntos
Corantes Fluorescentes , Xantonas , Cobre , Íons , Espectrometria de Fluorescência
20.
J Hazard Mater ; 417: 126030, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229380

RESUMO

In this work, we found that the distribution of two specific atrazine (ATZ) oxidation products (desethyl-atrazine (DEA) and desisopropyl-atrazine (DIA)) was different in oxidation processes involving aqueous ferryl ion (Fe(IV)) species and •OH. Specifically, the molar ratio of produced DEA to DIA (i.e., [DEA]/[DIA]) increased from 7.5 to 13 with increasing pH from 3 to 6 when ATZ was oxidized by Fe(IV), while the treatment of ATZ by •OH led to the [DEA]/[DIA] value of 2 which was independent of pH. Moreover, ATZ showed high reactivity towards Fe(IV) over a wide pH range, especially at near-neutral pH, at which ATZ oxidation in Fe(II)/peroxydisulfate system was even much faster than another well-defined Fe(IV) scavenger, the sulfoxides. By using this approach, it was obtained that the [DEA]/[DIA] value remained at 2 during ATZ transformation by the nitrilotriacetic acid (NTA) assisted Fenton-like (Fe(III)/H2O2) system, which was independent of solution pH and reactants dosage. This result clarified that •OH was the primary reactive intermediate formed in the NTA assisted Fe(III)/H2O2 system. This study not only developed a novel sensitive diagnostic tool for distinguishing Fe(IV) from •OH, but also provided more credible evidence to the nature of reactive intermediate in a commonly controversial system.


Assuntos
Atrazina , Compostos Férricos , Peróxido de Hidrogênio , Ácido Nitrilotriacético , Oxirredução
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