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1.
Food Chem ; 368: 130902, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34438176

RESUMO

Overcoming harsh gastric environment is still a challenging to bioactive proteins, microencapsulation provides one strategy in designing this protection barrier. In this work, bovine serum albumin and ovalbumin were chosen as model proteins, while polylysine-alginate complex was fabricated for microencapsulation purpose. Both of the protein-loaded microcapsules had regular internal microstructures. The model protein's embedding increased the thermal stability of the microcapsules. Both of the protein-loaded microcapsules had a slow release rate in simulated gastric fluids (pH 3.0), while a sustained release profile in simulated intestinal fluids (pH 6.4), indicating an excellent tolerance to the acidic gastric environment. The microencapsulation process was mild and had no influence on the protein's molecular weight, while a slight peak shifting occurred in the secondary structure of the released proteins. The developed microcapsules could be explored as a kind of vehicle for bioactive proteins applied in functional foods, health care products and medical formulations.


Assuntos
Polilisina , Soroalbumina Bovina , Alginatos , Cápsulas , Ovalbumina
2.
Cancer Lett ; 524: 206-218, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688842

RESUMO

Phosphatidylinositol 3-kinase (PI3K) δ-specific inhibitors have been approved for the therapy of certain types of B cell lymphoma (BCL). However, their clinical use is limited by the substantial toxicity and lack of efficacy in other types of BCL. Emerging evidence indicates that PI3Kα plays important roles in the progression of B cell lymphoma. In this study, we revealed that PI3Kα was important for the PI3K signaling and proliferation in BCL cells. A novel clinical PI3Kα-selective inhibitor CYH33 possessed superior activity against BCL compared to the marketed PI3Kα-selective inhibitor Alpelisib and PI3Kδ-selective inhibitor Idelalisib. Though CYH33 was able to inhibit PI3K/AKT signaling in tested BCL cells, differential activity against proliferation was observed. Transcriptome profiling revealed that CYH33 down-regulated "MYC-targets" gene set in sensitive but not resistant cells. CYH33 inhibited c-MYC transcription in sensitive cells, which was attributed to a decrease in acetylated H3 bound to the promoter and super-enhancer region of c-MYC. Accordingly, CYH33 treatment resulted in phosphorylation and proteasomal degradation of the histone acetyltransferase p300. An unbiased screening with drugs approved or in clinical trials for the therapy of BCL identified that the clinical BET (Bromodomain and Extra Terminal domain) inhibitor OTX015 significantly potentiated the activity of CYH33 against BCL in vitro and in vivo, which was associated with enhanced inhibition on c-MYC expression and induction of cell cycle arrest and apoptosis. Our findings provide the rationale of combined CYH33 with BET inhibitors for the therapy of B cell lymphoma.

3.
Neural Regen Res ; 17(5): 1023-1033, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34558529

RESUMO

The formation of nerve bundles, which is partially regulated by neural cell adhesion molecule 1 (NCAM1), is important for neural network organization during peripheral nerve regeneration. However, little is known about how the extracellular matrix (ECM) microenvironment affects this process. Here, we seeded dorsal root ganglion tissue blocks on different ECM substrates of peripheral nerve ECM-derived matrix-gel, Matrigel, laminin 521, collagen I, and collagen IV, and observed well-aligned axon bundles growing in the peripheral nerve ECM-derived environment. We confirmed that NCAM1 is necessary but not sufficient to trigger this phenomenon. A protein interaction assay identified collagen VI as an extracellular partner of NCAM1 in the regulation of axonal fasciculation. Collagen VI interacted with NCAM1 by directly binding to the FNIII domain, thereby increasing the stability of NCAM1 at the axolemma. Our in vivo experiments on a rat sciatic nerve defect model also demonstrated orderly nerve bundle regeneration with improved projection accuracy and functional recovery after treatment with 10 mg/mL Matrigel and 20 µg/mL collagen VI. These findings suggest that the collagen VI-NCAM1 pathway plays a regulatory role in nerve bundle formation. This study was approved by the Animal Ethics Committee of Guangzhou Medical University (approval No. GY2019048) on April 30, 2019.

4.
Methods Mol Biol ; 2392: 261-273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34773628

RESUMO

This chapter introduces neutralized DNA (nDNA) as a novel design for the primers of PCR and RT-PCR by methylating phosphate groups of some oligonucleotides in their structures. It starts with an introduction of the nDNA which possesses an electrically chimeric neutral backbone as well as the proposed standards in designing nDNA as a novel primer for PCR and RT-PCR , concluded from various experimental results presented afterward. The primary content comprises empirical data from PCR to compare nDNA and unmodified DNA as primers in terms of ability to distinguish and amplify mismatch templates, activities of polymerase enzymes, melting temperature of double-stranded sequences, and the trials and discussions on various modified positions of the nDNA primers. In summary, nDNA exhibited outstanding performance as a primer for PCR and RT-PCR , compared to unmodified DNA, and is expected to be expanded in diverse applications which require enhanced specificity.

5.
Protein Expr Purif ; 190: 106003, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34688919

RESUMO

SARS-CoV-2 protein subunit vaccines are currently being evaluated by multiple manufacturers to address the global vaccine equity gap, and need for low-cost, easy to scale, safe, and effective COVID-19 vaccines. In this paper, we report on the generation of the receptor-binding domain RBD203-N1 yeast expression construct, which produces a recombinant protein capable of eliciting a robust immune response and protection in mice against SARS-CoV-2 challenge infections. The RBD203-N1 antigen was expressed in the yeast Pichia pastoris X33. After fermentation at the 5 L scale, the protein was purified by hydrophobic interaction chromatography followed by anion exchange chromatography. The purified protein was characterized biophysically and biochemically, and after its formulation, the immunogenicity was evaluated in mice. Sera were evaluated for their efficacy using a SARS-CoV-2 pseudovirus assay. The RBD203-N1 protein was expressed with a yield of 492.9 ± 3.0 mg/L of fermentation supernatant. A two-step purification process produced a >96% pure protein with a recovery rate of 55 ± 3% (total yield of purified protein: 270.5 ± 13.2 mg/L fermentation supernatant). The protein was characterized to be a homogeneous monomer that showed a well-defined secondary structure, was thermally stable, antigenic, and when adjuvanted on Alhydrogel in the presence of CpG it was immunogenic and induced high levels of neutralizing antibodies against SARS-CoV-2 pseudovirus. The characteristics of the RBD203-N1 protein-based vaccine show that this candidate is another well suited RBD-based construct for technology transfer to manufacturing entities and feasibility of transition into the clinic to evaluate its immunogenicity and safety in humans.


Assuntos
Vacinas contra COVID-19 , Expressão Gênica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/farmacologia , Humanos , Camundongos , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , SARS-CoV-2/química , SARS-CoV-2/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/farmacologia
6.
J Colloid Interface Sci ; 607(Pt 2): 1457-1465, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34598027

RESUMO

Lithium iron phosphate (LFP) is one of the promising cathode materials of lithium ion battery (LIB), but poor electrical conductivity restricts its electrochemical performance. Carbon coating can improve electrical conductivity of LFP without changing its intrinsic property. Uniform coating of carbon on LFP is significant to avoid charge congregation and unpreferable redox reactions. It is the first time to apply the commercial organic binder, Super P® (SP), as carbon source to achieve uniform coating on LFP as cathode material of LIB. The simple and economical mechanofusion method is firstly applied to coat different amounts of SP on LFP. The LIB with the cathode material of optimized SP-coated LFP shows the highest capacity of 165.6 mAh/g at 0.1C and 59.8 mAh/g at 10C, indicating its high capacity and excellent high-rate charge/discharge capability. SP is applied on other commercial LFP materials, M121 and M23, for carbon coating. Enhanced high-rate charge/discharge capabilities are also achieved for LIB with SP-coated M121 and M23 as cathode materials. This new material and technique for carbon coating is verified to be applicable on different LFP materials. This novel carbon coating method is expected to apply on other cathode materials of LIB with outstanding electrochemical performances.

7.
Anal Chim Acta ; 1189: 339218, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815039

RESUMO

Metabolomics, which serves as a readout of biological processes and diseases monitoring, is an informative research area for disease biomarker discovery and systems biology studies. In particular, reversed-phase liquid chromatography-mass spectrometry (RPLC-MS) has become a powerful and popular tool for metabolomics analysis, enabling the detection of most metabolites. Very polar and ionic metabolites, however, are less easily detected because of their poor retention in RP columns. Dansylation of metabolites simplifies the sub-metabolome analysis by reducing its complexity and increasing both hydrophobicity and ionization ability. However, the various metabolite concentrations in clinical samples have a wide dynamic range with highly individual variation in total metabolite amount, such as in saliva. The bicarbonate buffer typically used in dansylation labeling reactions induces solvent stratification, resulting in poor reproducibility, selective sample loss and an increase in false-determined metabolite peaks. In this study, we optimized the dansylation protocol for samples with wide concentration range of metabolites, utilizing diisopropylethylamine (DIPEA) or tri-ethylamine (TEA) in place of bicarbonate buffer, and presented the results of a systemic investigation of the influences of individual processes involved on the overall performance of the protocol. In addition to achieving high reproducibility, substitution of DIPEA or TEA buffer resulted in similar labeling efficiency of most metabolites and more efficient labeling of some metabolites with a higher pKa. With this improvement, compounds that are only present in samples in trace amounts can be detected, and more comprehensive metabolomics profiles can be acquired for biomarker discovery or pathway analysis, making it possible to analyze clinical samples with limited amounts of metabolites.


Assuntos
Aminas , Fenol , Compostos de Dansil , Marcação por Isótopo , Fenóis , Reprodutibilidade dos Testes , Solventes
8.
J Colloid Interface Sci ; 606(Pt 1): 406-423, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392035

RESUMO

Carbonaceous microwave absorbing materials are in vital demand due to the extensive electromagnetic pollution in 5G network era and urgent requirements for stealth technology in national defense domain. Rather than the complicated vapor deposition method, a simple biomass-derived approach sheds light on the mass production of carbon materials for its ubiquitous, environmental-friendly, cost-off, and sustainable advantages. Herein, a concise review of recent advances in designing carbonaceous materials for EM attention is provided with particular stress on the biomass categories and the synthetic method. The three dimensional (3D) interconnected network of carbon materials are highlighted in analysis regarding the biomass selection, functional process, pore-forming strategy and the microwave absorption performance of the corresponding composites. Nature fiber-derived carbon materials, possessing high-aspect ratio fiber structure, are also discussed due to their potential in weaving manufacture and diverse application for flexible cloaking fabric. In the end, the current challenge and the directional perspective for utilizing biomass-derived carbon absorbing materials with effective EM properties are outlined.


Assuntos
Carbono , Micro-Ondas , Biomassa
9.
J Colloid Interface Sci ; 607(Pt 2): 1023-1035, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34571292

RESUMO

HYPOTHESIS: The imbibition dynamics is controlled by energy dissipation mechanisms and influenced by asymmetric wettability in a nanochannel. We hypothesize that the imbibition dynamics can be described by a combined model of the Lucas-Washburn equation and the Cox-Voinov law considering velocity-dependent contact angles. METHODS: Molecular dynamics simulations are utilized to investigate the imbibition dynamics. A wide range of wetting conditions is achieved via adjusting the liquid-solid interaction parameters, and the spontaneous imbibition processes are quantified and compared. FINDINGS: The critical condition for the occurrence of spontaneous imbibition is analyzed from a surface energy perspective. The analyses of energy conversion and dissipation indicate that the viscous dissipation is dominant during spontaneous imbibition. The classical Lucas-Washburn equation is modified with the Cox-Voinov law considering the effect of the dynamic contact angle and an effective equilibrium contact angle. We show that the proposed theory well captures the imbibition dynamics embodied in the growth of imbibition length as well as the transient interface shape and velocity for both the symmetric and asymmetric wetting conditions. In nanochannels with asymmetric wettability, the imbibition length difference between the sidewalls and interface oscillations increases with wetting disparity. Our findings deepen the understanding of imbibition dynamics on the nanoscale, and provide a theoretical reference for relevant applications.

10.
Chemosphere ; 286(Pt 2): 131770, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34364234

RESUMO

Antibiotic compounds have caused serious environmental concerns. In this study, we developed an effective technology for treatment of chlortetracycline (CTC), a widely used antibiotic compound. A natural heteroatom-doped spent tea leaves-based biochar (STLB) with excellent adsorption and catalytic property was prepared by simple thermal treatment. An adsorption-promoted persulfate-based advanced oxidation process (PS-AOP) using STLB was studied for CTC removal. The results showed that the as-prepared STLB presented favorable adsorption affinity towards CTC with the maximum adsorption capacity of 627 mg g-1. Meanwhile, CTC enriched on the surface of STLB was good for in-situ decomposition of CTC and nearly 97.4 % of CTC was removed within 30 min of pre-adsorption and 60 min of subsequent degradation. The STLB had excellent recyclability and wide pH tolerance range of 3.0-9.0 in combined pre-adsorption and PS-AOP. Reactive oxygen species analysis confirmed that CTC degradation was mainly due to non-radical (singlet oxygen, 1O2) and radicals (SO4- and OH). This study suggests that STLB is a promising adsorption-enhanced PS activator for the treatment of refractory wastewater and also provides a strategy of waste control by spent tea leaves.


Assuntos
Clortetraciclina , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Folhas de Planta/química , Chá , Água , Poluentes Químicos da Água/análise
11.
Neural Regen Res ; 17(1): 137-143, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34100449

RESUMO

The survival of microglia depends on the colony-stimulating factor-1 receptor (CSF1R) signaling pathway under physiological conditions. Ki20227 is a highly selective CSF1R inhibitor that has been shown to change the morphology of microglia. However, the effects of Ki20227 on the progression of ischemic stroke are unclear. In this study, male C57BL/6 mouse models of focal cerebral ischemic injury were established through the occlusion of the middle cerebral artery and then administered 3 mg/g Ki20227 for 3 successive days. The results revealed that the number of ionized calcium-binding adaptor molecule 1/bromodeoxyuridine double positive cells in the infarct tissue was reduced, the degree of edema was increased, neurological deficits were aggravated, infarct volume was increased, and the number of peri-infarct Nissl bodies was reduced. The number of terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive cells in the peri-infarct tissue was increased. The expression levels of Bax and Cleaved caspase-3 were up-regulated. Bcl-2 expression was downregulated. The expression levels of inflammatory factors and oxidative stress-associated factors were increased. These findings suggested that Ki20227 blocked microglial proliferation and aggravated the pathological progression of ischemia/reperfusion injury in a transient middle cerebral artery occlusion model. This study was approved by the Animal Ethics Committee of Lanzhou University Second Hospital (approval No. D2020-68) on March 6, 2020.

12.
J Hazard Mater ; 423(Pt B): 127103, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34534809

RESUMO

N-doped hierarchical porous carbons (NHPCs) were successfully prepared from soft-templated zeolitic imidazolate framework-8 (ZIF-8) precursors using sodium dodecylbenzene sulfonate (SDBS) as a template through facile one-step carbonization and applied in tetracycline hydrochloride (TCH) adsorption. The NHPC synthesized at 1000 °C with an SDBS/Zn2+ molar ratio of 0.075 exhibited the highest TCH adsorption (qm = 80.92 mg g-1) owing to its relatively large BET surface area (1067.41 m2 g-1) and pore volume (1.22 cm3 g-1) and the stronger surface interaction between TCH and NHPCs (HC1000-0.075). Compared with surfactant-free ZIF-8-derived carbon (HC), introduction of SDBS in the ZIF-8 precursor not only improved the pore structure of the carbon materials but also increased the nitrogen content and the number of surface functional groups. Adsorption kinetics and isotherms showed that the pseudo-second-order model and Sips model fit the TCH adsorption behavior on HC and HC1000-0.075 well. Adsorption experiments and characterizations revealed that the adsorption mechanism involved in TCH adsorption on HC1000-0.075 mainly depended on the synergistic effect of pore filling, H-bonding, π-π interactions, and weak electrostatic interactions. This study provides an effective and simple strategy for fabricating MOF-derived NHPCs as a promising adsorbent for the removal of antibiotics from water.

13.
J Ethnopharmacol ; 283: 114648, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34543684

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Isatidis Radix (called Banlangen, BLG in Chinese) and Isatidis Folium (called Daqingye, DQY in Chinese) are common traditional edible-medicinal herbs in detoxifying for thousands of years, have been traditionally applied in traditional Chinese medicine for centuries. Both of them are bitter in taste, coolness in nature, acting on the heart and stomach channels. They are often used to treat influenza and other viral infectious diseases in clinic, as well as could treat fever, dizziness, and cough and sore throat caused by lung heat. AIMS OF THE REVIEW: This review aimed at summarizing the latest and comprehensive information of BLG and DQY on the ethnopharmacology, phytochemistry, pharmacology, toxicity and clinical application to explore the therapeutic potential of them. In addition, outlooks and perspective for possible future researches that related are also discussed. MATERIALS AND METHODS: Related information concerning BLG and DQY were gathered from the internet database of Google Scholar, PubMed, Baidu Scholar, GeenMedical, CNKI and Web of Science, as well as other relevant textbooks, reviews, and documents (e.g., Chinese Pharmacopoeia, 2020 edition, Chinese herbal classic books and PhD and MSc thesis, etc.). Among of them with the keywords including "Isatis indigotica" "Isatidis Radix", "Isatidis Folium", "phytochemistry", "pharmacology", "toxicology", "clinical application" etc. and their combinations. RESULTS: To date, 39 Chinese patent medicines containing BLG and/or DQY have been developed on basis of the data of NMPA. Besides, 304 and 142 compounds have been found in BLG and DQY, respectively. The main chemical differences between BLG and DQY were concentrated on alkaloids and lignans, such as indican, indirubin, (R, S)-epigoitrin, 4(3H)-quinazolinone, clemastanin B and isatindigotindolines A-D. In 2020 Edition ChP, (R, S)-goitrin and indirubin are now used as the official marker to monitor the quality of BLG and DQY, respectively. Modern pharmacology has mainly studied some monomer components such as 4(3H)-quinazolinone, clemastanin B, erucic acid and adenosine, etc., all of which have shown good effects. These active compounds can resist various viruses, such as influenza virus, respiratory syncytial virus, herpes simplex virus, etc.. By regulating the level of immunity and a variety of inflammatory factors, inhibit the growth and reproduction of the virus. At the same time, it is worth noting that different components of BLG and DQY lead to BLG is more powerful in antiviral and immunomodulatory activity than DQY, while DQY possesses a higher intensity than BLG in anti-oxidant activity. CONCLUSION: By collecting and collating a large number of literature and various data websites, we concluded that the common compounds are mainly alkaloids. Recent findings regarding the phytochemical and pharmacological properties of BLG and DQY have confirmed their traditional uses in antiviral, antibacterial and treatment immune diseases. Without doubt, their significant differences on ethnopharmacology, phytochemistry and pharmacology can be used as evidence of separate list of BLG and DQY. For shortcomings, some comprehensive studies should be well designed for further utilization of BLG and DQY.

14.
J Affect Disord ; 296: 277-282, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34628248

RESUMO

BACKGROUND: After isotretinoin's approval to treat patients with recalcitrant acne, there have been continued debates around its psychiatric safety profile. This study aimed to assess the risk of psychiatric disorders in patients with acne who are taking isotretinoin. METHODS: We used de-identified information from Taiwan's National Health Insurance Research Database from 2000 to 2015 to examine the risk for psychiatric disorders among patients with acne who were taking isotretinoin. We performed subgroup analyses based on the dosage and duration of isotretinoin administration. RESULTS: This study included 29,943 participants during a 16-year follow-up period. We found no significantly increased risk for psychiatric disorders among patients taking isotretinoin compared with patients who did not receive isotretinoin treatment (adjusted hazard ratio [aHR]: 1.009, 95% confidence interval [CI]: 0.422-1.696). Subgroup analyses showed no significantly increased risk for psychiatric disorders in patients taking different doses of isotretinoin (≤ 20 mg per day, aHR: 0.892, 95% CI: 0.371-1.501; > 20 mg per day, aHR: 1.068, 95% CI: 0.446-1.798). There was also no significant increase in risk for patients undergoing isotretinoin treatment over different periods (≤ 6 months, aHR: 0.924, 95% CI: 0.392-1.612; > 6 months, aHR: 1.196, 95% CI: 0.488-2.004). LIMITATIONS: We did not analyze the risk of suicidal ideation, and it could be underestimated in medical claims databases. CONCLUSIONS: We found no increased risk of psychiatric disorders among Taiwanese patients with acne who were taking isotretinoin. Higher dosage or longer duration of isotretinoin treatment did not increase the risk for developing a psychiatric disorder.

15.
Food Chem ; 371: 131154, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598120

RESUMO

The influence of acidity regulators and buffers on the formation of acrylamide (AA) and 5-hydroxymethylfurfural (5-HMF) in French fries and the underlying mechanism were evaluated. Prior to frying, the potato strips were dipped in the corresponding acidity regulator solutions or buffers for 30 min at room temperature. The results showed that acids inhibited AA formation, but increased 5-HMF levels. The AA level decreased and 5-HMF level increased with decreasing pH of potato strips. Interestingly, increasing concentration of acid radical ions resulted in AA increase and 5-HMF decrease, which was opposite to the acidification effect of citric acid and acetic acid. Both pH and acid radical ion were important factors for AA and 5-HMF formation. Moreover, acidity regulators might impact AA formation by acting on the generation of methylglyoxal (MGO) and glyoxal (GO) and impact 5-HMF formation by acting on the generation of 3-deoxyglucosone (3-DG).


Assuntos
Acrilamida , Solanum tuberosum , Furaldeído/análogos & derivados , Temperatura Alta , Concentração de Íons de Hidrogênio , Íons
16.
J Sci Food Agric ; 102(1): 341-349, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111305

RESUMO

BACKGROUND: Neonicotinoids are widely used insecticides, and tea is a popular non-alcoholic beverage in Taiwan. However, the levels of neonicotinoids in Taiwanese tea leaves remain unclear. Therefore, this study aims to understand the characteristics of neonicotinoid and metabolite residues in Taiwanese tea leaves. METHODS: In this study, 12 tea leaf samples were collected in Taiwan and extracted by solid-phase extraction before analysis by liquid chromatography-tandem mass spectrometry. In addition, the levels of neonicotinoids were compared with the maximum residue level standards from other countries. RESULTS: In Taiwanese tea leaves, five neonicotinoids and seven metabolites were detected. Different tea species influenced the levels of neonicotinoids and their metabolites in the present study. Moreover, the levels of neonicotinoids and their metabolites in partially fermented leaves were higher than in completely fermented leaves. In Jin-Xuan tea, the levels of neonicotinoids and their metabolites in most winter-harvested teas were lower than in summer-harvested teas. CONCLUSION: The residue levels of neonicotinoids and their metabolites were detectable in Taiwanese tea leaves. Moreover, different tea species, manufacturing processes, and harvest seasons might influence the levels of these pesticides. Therefore, the government should monitor the use of neonicotinoids. © 2021 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Inseticidas/análise , Neonicotinoides/análise , Resíduos de Praguicidas/análise , Cromatografia Líquida , Contaminação de Alimentos/análise , Folhas de Planta/química , Extração em Fase Sólida , Taiwan , Espectrometria de Massas em Tandem , Chá/química
17.
Anticancer Res ; 41(12): 6095-6104, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34848464

RESUMO

BACKGROUND/AIM: This study investigated the anti-metastatic effects of cetyltrimethylammonium bromide (CTAB) on tongue squamous cell carcinoma (TSCC) SCC4 cells. MATERIALS AND METHODS: Cell morphology, viability, cell cycle distribution, adhesion, migration, invasion and the expression levels of associated proteins were examined using microscopy, WST-1, wound-healing, Boyden chamber assays, and western blotting, respectively. RESULTS: CTAB significantly affected SCC4 cell morphology from spindle-shaped to cobblestone-shaped and resulted in loss of adherence. CTAB significantly inhibited cell adhesion, migration, and invasion of SCC4 cells, independent of cell viability. CTAB reduced expression of matrix metalloproteinases (MMPs) such as MMP3, MMP7, and MMP14 in a concentration-dependent manner, while it increased expression of tissue inhibitors of metalloproteinase 3 (TIMP3). In addition, CTAB reduced the phosphorylation of mothers against decapentaplegic homolog 2/3 (Smad2/3) proteins, which mediated CTAB-inhibited migration and invasion in SCC4 cells. These effects were reversed by TGF-ß1. CONCLUSION: CTAB attenuates the mesenchymal characteristics through upregulation of TIMP3 by inhibiting the canonical TGF-ß/Smad/miR-181b/TIMP3 signaling involved in extracellular matrix remodeling in SCC4 cells and might be a promising anti-metastatic therapeutic agent for TSCC.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34850009

RESUMO

OBJECTIVES: There is an urgent need for novel drugs that target unique cellular pathways to combat infections caused by Mycobacterium tuberculosis. CRISPR interference (CRISPRi)-mediated transcriptional repression has recently been developed for use in mycobacteria as a genetic tool for identifying and validating essential genes as novel drug targets. Whilst CRISPRi has been applied to extracellular bacteria, no studies to date have determined whether CRISPRi can be used in M. tuberculosis infection models. METHODS: Using the human monocytic macrophage-like THP-1 cell line as a model for M. tuberculosis infection we investigated if CRISPRi can be activated within intracellular M. tuberculosis. RESULTS: The transcriptional repression of two candidate M. tuberculosis genes, i.e. mmpL3 and qcrB, leads to a reduction in viable M. tuberculosis within infected THP-1 cells. The reduction in viable colonies is dependent on both the level of CRISPRi-mediated repression and the duration of repression. CONCLUSIONS: These results highlight the utility of CRISPRi in exploring mycobacterial gene function and essentiality under a variety of conditions pertinent to host infection.

19.
Environ Sci Technol ; 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732048

RESUMO

Nitro-phenolic compounds (NPs) have attracted increasing attention because of their health risks and impacts on visibility, climate, and atmospheric chemistry. Despite many measurements of particulate NPs, the knowledge of their gaseous abundances, sources, atmospheric fates, and impacts remains incomplete. Here, 18 gaseous NPs were continuously measured with a time-of-flight chemical ionization mass spectrometer at a background site in South China in autumn and winter. Abundant NPs were observed in the continental outflows from East Asia, with a total concentration up to 122.1 pptv. Secondary formation from the transported aromatics dominated the observed NPs, with mono-NPs exhibiting photochemical daytime peaks and nighttime enrichments of di-NPs and Cl-substituted NPs. The budget analysis indicates that besides the •OH oxidation of aromatics, the NO3• oxidation also contributed significantly to the daytime mono-NPs, while the further oxidation of mono-NPs by NO3• dominated the nocturnal formation of di-NPs. Photolysis was the main daytime sink of NPs and produced substantial HONO, which would influence atmospheric oxidation capacity in downwind and background regions. This study provides quantitative insights on the formation and impacts of gaseous NPs in the continental outflow and highlights the role of NO3• chemistry in the secondary nitro-aromatics production that may facilitate regional pollution.

20.
Anim Nutr ; 7(4): 1024-1030, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34738032

RESUMO

This study aimed to evaluate role of nano-sized zinc (Zn) on lactation performance, health status, and mammary permeability of lactating dairy cows. Thirty multiparous dairy cows with similar days in milk (158 ± 43.2) and body weight (694 ± 60.5 kg) were chosen based on parity and milk production and were randomly assigned to 3 treatment groups: basal diet (control, 69.6 mg/kg of Zn adequate in Zn requirement), basal diet additional Zn-methionine (Zn-Met, providing 40 mg/kg of Zn), and basal diet additional nano-sized Zn oxide (nZnO, providing 40 mg/kg of Zn). The study lasted for 10 wk, with the first 2 wk as adaptation. Feed intake, milk yield and the related variables, and plasma variables were determined every other week. Blood hematological profiles were determined in the 8th week of the study. We found that feed intake, milk yield, and milk composition were similar across the 3 groups. The nZnO- and Zn-Met-fed cows had greater milk Zn concentrations in the milk (3.89 mg/L (Zn-Met) and 3.93 mg/L (nZnO)) and plasma (1.25 mg/L (Zn-Met) and 1.29 mg/L (nZnO)) than the control cows (3.79 mg/L in milk and 1.21 mg/L in plasma). The nZnO-fed cows had higher Zn concentrations in plasma but not in milk compared to Zn-Met-fed cows. The Zn appearance in milk was greater in nZnO-fed (area under curve during the first 4 h post-feeding for milk Zn: 16.1 mg/L) and Zn-Met-fed cows (15.7 mg/L) than in control cows (15.0 mg/L). During the first 4 h post-feeding, milk to blood Zn ratio was greater in nZnO-fed animals but lower in Zn-Met-fed cows compared with control cows. Oxidative stress-related variables in plasma, blood hematological profiles, and mammary permeability related variables were not different across treatments. In summary, lactation performance, Zn concentrations in milk and plasma, hematological profiles, mammary permeability were similar in cows fed nZnO and Zn-Met. We therefore suggested that nZnO feeding can improve Zn bioavailability without impairing lactation performance, health status, and mammary gland permeability in dairy cows.

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