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1.
Inorg Chem ; 63(4): 2282-2288, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38232293

RESUMO

A highly promising electrocatalyst has been designed and prepared for the hydrogen evolution reaction (HER). This involves incorporating well-dispersed Ir nanoparticles into a cobalt-based metal-organic framework known as Co-BPDC [Co(bpdc)(H2O)2, BPDC: 4,4'-biphenyldicarboxylic acid]. Ir@Co-BPDC demonstrates exceptional HER activity in alkaline media, surpassing both commercial Pt/C and recent noble-metal catalysts. Theoretical results indicate that electron redistribution, induced by interfacial bonds, optimizes the adsorption energy of water and hydrogen, thereby enhancing our understanding of the superior properties of Ir@Co-BPDC for HER.

2.
Anal Chem ; 95(49): 18207-18214, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38010370

RESUMO

Owing to excellent catalytic activity, single-atom catalysts (SACs) have recently attracted considerable research interest in the electrochemiluminescence (ECL) field. However, the applications of SACs are mostly limited to conventional luminol ECL system. Hence, it is necessary to explore the application of SACs in more ECL systems. In this work, nickel single-atom catalysts (Ni SACs) were successfully applied in the graphitic carbon nitride (g-C3N4)-H2O2 ECL system to significantly enhance its cathodic emission. Notably, g-C3N4 acted not only as an ECL luminophore but also as a support to anchor Ni SACs. Ni SACs can significantly activate H2O2 to produce abundant OH• radicals for enhancing the cathodic ECL emission of g-C3N4. Ni SACs-anchored g-C3N4 (Ni SACs@g-C3N4) had a 10-fold enhanced ECL intensity as compared to g-C3N4. Finally, the Ni SACs@g-C3N4-H2O2 ECL system was developed to detect hepatitis B virus (HBV) DNA by incorporating an entropy-driven DNA walking machine-assisted CRISPR-Cas12a amplification strategy. The constructed biosensor exhibited excellent detection performance for HBV DNA with a limit of detection as low as 17 aM. This work puts forward a new idea for enhancing the cathodic ECL of g-C3N4-H2O2 and expands the application of SACs in the ECL system.


Assuntos
Técnicas Biossensoriais , DNA Viral , Níquel , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Medições Luminescentes , Limite de Detecção
3.
Avian Pathol ; 52(1): 12-24, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35980124

RESUMO

The aim of this study was to evaluate the effects of anti-stress agents on the growth performance and immune function of broilers under immune stress conditions induced by vaccination. A total of 128, 1-day-old Arbor Acres broilers were randomly divided into four groups. Group normal control (NC) was the control group. Group vaccination control (VC), T 0.5%, and T 1% were the treatment groups, which were nasally vaccinated with two doses of the Newcastle disease virus (NDV) vaccine. The chicks in groups T 0.5% and T 1% were fed conventional diets containing 0.5% and 1% anti-stress agents. Thereafter, these broilers were slaughtered on 1, 7, 14, and 21 days post-vaccination. The results indicated that anti-stress agents could significantly reduce serum adrenocorticotropic hormone (ACTH) (P < 0.01) and cortisol (CORT) (P < 0.05) levels, and improve the growth performance (P < 0.05) and immune function of broilers (P < 0.05); However, the levels of malondialdehyde (MDA) (P < 0.05) were decreased, and the decreased total antioxidant capacity (T-AOC) (P < 0.01) levels mediated by vaccination were markedly improved. In addition, anti-stress agents could attenuate apoptosis in spleen lymphocytes (P < 0.01) by upregulating the ratio of Bcl-2 to BAX (P < 0.01) and downregulating the expression of caspase-3 and -9 (P < 0.01), which might be attributed to the inhibition of the enzymatic activities of caspase-3 and -9 (P < 0.05). In conclusion, anti-stress agents may improve growth performance and immune function in broilers under immune-stress conditions.RESEARCH HIGHLIGHTS Investigation of effects and mechanism of immune stress induced by vaccination.Beneficial effect of anti-stress agents on growth performance, immune function, oxidative stress, and regulation of lymphocyte apoptosis.Demonstration of the effects of apoptosis on immune function in the organism.


Assuntos
Antioxidantes , Galinhas , Animais , Caspase 3/metabolismo , Antioxidantes/metabolismo , Dieta/veterinária , Vacinação/veterinária , Imunidade , Ração Animal/análise , Suplementos Nutricionais
4.
Ecotoxicol Environ Saf ; 238: 113561, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35489292

RESUMO

Zearalenone (ZEA) is a nonsteroidal estrogenic mycotoxin, which mainly contaminates grains and has estrogen-like effects on the reproductive system. Betulinic acid (BA), a natural lupane-type pentacyclic triterpene, has anti-oxidative and anti-inflammatory properties. This study aimed to investigate whether BA alleviates ZEA-induced testicular damage and explore the possible mechanism. Here, BA ameliorated testicular damage by mitigating the disordered arrangement of seminiferous tubules, the exfoliation of lumen cells, and the increase of cell apoptosis caused by ZEA. Meanwhile, BA alleviated ZEA-triggered testicular damage by restoring hormone levels and sperm motility, and reconstructing the blood-testis-barrier. Moreover, BA alleviated ZEA-exposed testicular oxidative stress by activating Nrf2 pathway. Furthermore, BA moderated ZEA-evoked testicular inflammation by inhibiting p38/ERK MAPK pathway. Overall, our results revealed that BA has a therapeutic protective effect on ZEA-induced testicular injury and oxidative stress via p38/ERK MAPK inhibition and Nrf2-mediated antioxidant defense activation, which provides a viable alternative to alleviate ZEA-induced male reproductive toxicology.


Assuntos
Sistema de Sinalização das MAP Quinases , Fator 2 Relacionado a NF-E2 , Triterpenos Pentacíclicos , Testículo , Zearalenona , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Triterpenos Pentacíclicos/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Zearalenona/toxicidade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ácido Betulínico
5.
Toxicol Appl Pharmacol ; 432: 115753, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637808

RESUMO

T-2 toxin is a highly toxic trichothecene that can induce toxic effects in a variety of organs and tissues, but the pathogenesis of its nephrotoxicity has not been elucidated. In this study, we assessed the involvement of protein kinase RNA-like ER kinase (PERK)-mediated endoplasmic reticulum (ER) stress and apoptosis in PK-15 cells cultured at different concentrations of T-2 toxin. Cell viability, antioxidant capacity, intracellular calcium (Ca2+) content, apoptotic rate, levels of ER stress, and apoptosis-related proteins were studied. T-2 toxin inhibited cell proliferation; increased the apoptosis rate; and was accompanied by increased cleaved caspase-3 expression, altered intracellular oxidative stress marker levels, and intracellular Ca2+ overloading. The ER stress inhibitor 4-phenylbutyrate (4-PBA) and PERK selective inhibitor GSK2606414 prevented the decrease of cell activity and apoptosis caused by T-2 toxin. The altered expression of glucose regulatory protein 78 (GRP78), C/EBP homologous protein (CHOP), and caspase-12 proved that ER stress was involved in cell injury triggered by T-2 toxin. T-2 toxin activated the phosphorylation of PERK and the alpha subunit of eukaryotic initiation factor 2 (eIF2α) and upregulated the activating transcription factor 4 (ATF4), thereby triggering ER stress via the GRP78/PERK/CHOP signaling pathway. This study provides a new perspective for understanding the nephrotoxicity of T-2 toxin.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/metabolismo , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Toxina T-2/toxicidade , eIF-2 Quinase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 12/metabolismo , Linhagem Celular , Chaperona BiP do Retículo Endoplasmático/metabolismo , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Rim/enzimologia , Rim/patologia , Nefropatias/enzimologia , Nefropatias/patologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais , Sus scrofa , Fator de Transcrição CHOP/metabolismo
6.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769202

RESUMO

Treatment of neoplastic diseases in companion animals is one of the most important problems of modern veterinary medicine. Given the growing interest in substances of natural origin as potential anti-cancer drugs, our goal was to examine the effectiveness of benzyl isothiocyanate (BITC), a compound found in cruciferous vegetables, against canine lymphoma and leukemia. These are the one of the most common canine cancer types, and chemotherapy is the only treatment option. The study involved established cell lines originating from various hematopoietic malignancies: CLBL-1, GL-1, CLB70 and CNK-89, immortalized noncancerous cell lines: MDCK and NIH-3T3 and canine peripheral blood mononuclear cells (PBMCs). The cytotoxic activity of BITC, apoptosis induction, caspase activity and ROS generation were evaluated by flow cytometry. H2AX phosphorylation was assessed by western blot. The study showed that the compound was especially active against B lymphocyte-derived malignant cells. Their death resulted from caspase-dependent apoptosis. BITC induced ROS accumulation, and glutathione precursor N-acetyl-l-cysteine reversed the effect of the compound, thus proving the role of oxidative stress in BITC activity. In addition, exposure to the compound induced DNA damage in the tested cells. This is the first study that provides information on the activity of BITC in canine hematopoietic malignancies and suggests that the compound may be particularly useful in B-cell neoplasms treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Doenças do Cão/tratamento farmacológico , Isotiocianatos/farmacologia , Leucemia/veterinária , Linfoma/veterinária , Animais , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Doenças do Cão/genética , Doenças do Cão/metabolismo , Cães/genética , Cães/metabolismo , Isotiocianatos/química , Leucemia/tratamento farmacológico , Leucemia/genética , Leucemia/metabolismo , Linfoma/tratamento farmacológico , Linfoma/genética , Linfoma/metabolismo , Células Madin Darby de Rim Canino , Camundongos , Células NIH 3T3 , Espécies Reativas de Oxigênio/metabolismo , Verduras/química
7.
Reproduction ; 158(6): R209-R218, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31677601

RESUMO

In this paper, we propose the reproductive stress hypothesis that describes the pregnant females response to reproductive events based upon the activation of the hypothalamic-pituitary-adrenal axis and sympathetic adrenomedullary system. The main components of the reproductive stress hypothesis can be summarized as follows: (1) events unique to reproduction including empathema, pregnancy, parturition and lactation cause non-specific responses in females, called active reproductive stress; (2) the fetus is a special stressor for pregnant females where endocrine hormones, including corticotropin-releasing hormones and fetal glucocorticoids secreted by the fetus and placenta, enter the maternal circulatory system, leading to another stress response referred to as passive reproductive stress and (3) response to uterine tension and intrauterine infection is the third type of stress, called fetal intrauterine stress. Appropriate reproductive stress is a crucial prerequisite in normal reproductive processes. By contrast, excessive or inappropriate reproductive stress may result in dysfunctions of the reproductive system, such as compromised immune function, leading to susceptibility to disease. The novel insights of the reproductive stress hypothesis have important implications for deciphering the pathogenesis of certain diseases in pregnant animals, including humans, which in turn may be applied to preventing and treating their occurrence.


Assuntos
Feto/fisiopatologia , Hormônios/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Reprodução , Estresse Fisiológico , Animais , Feminino , Humanos , Gravidez
8.
Analyst ; 144(13): 3967-3971, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31140474

RESUMO

An OFF-ON detection method for Cu2+ was developed at the AgAu bimetallic nanoparticle decorated nitrogen-doped graphene (AgAu-NG) nanocomposite modified electrode. The measurement was based on the copper-catalyzed oxidation of cysteamine (Cys) to regulate the oxidation peak current of Ag. In the absence of Cu2+, Cys can bind to the surface of AgAu-NG via the Ag-S or Au-S bond, thus leading to an obvious decrease of the oxidation peak current of Ag. However, in the presence of Cu2+, Cu2+ can greatly catalyze the oxidation of Cys by dissolved O2 to form cystamine, which would fall off the surface of AgAu-NG nanocomposites, leading to the partial recovery of the oxidation peak current of Ag. With the increase in the concentration of Cu2+, the oxidation peak current of Ag in the presence of Cys increases accordingly. So, the concentration of Cu2+ can be measured. By using the optimum conditions, this method can detect Cu2+ concentrations down to 0.3 nM (S/N = 3) with a linear response range of 1 nM-1 mM. Furthermore, this method was applied to determine Cu2+ concentrations in river water samples and showed excellent analytical performance.

9.
Nanotechnology ; 30(28): 285502, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30884476

RESUMO

In this paper, a novel electrochemical sensor based on Au nanoparticles/8-aminoquinoline functionalized graphene oxide (AuNPs/GAQ) nanocomposite was developed and tested for the first time for detection of paraquat (PQ). The morphology and composition of AuNPs/GAQ nanocomposite were characterized by various techniques, including transmission electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and x-ray photoelectron spectroscopy. Cyclic voltammetry and differential pulse voltammetry were utilized to investigate the electrochemical performances of AuNPs/GAQ nanocomposite modified glassy carbon electrode. The obtained modified electrode exhibited excellent electrocatalytic activity towards detection of PQ. Under the optimized conditions, the proposed sensor showed low detection limit (6 nM, S/N = 3), wide linear range (0.02-24 µM), high selectivity and good stability. In addition, it was successfully applied for detection of PQ in natural water samples with satisfactory results.

10.
Mikrochim Acta ; 186(5): 321, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049702

RESUMO

A glassy carbon electrode (GCE) was modified with a nanocomposite prepared from nitrogen-doped reduced graphene oxide (N-rGO) and single walled carbon nanotubes (SWCNTs), and then loaded with platinum nanoparticles (Pt NPs) to obtain a voltammetric sensor for daunorubicin (DNR). Reductive doping of GO and the crystallization of the Pt NPs were carried out in a one-step hydrothermal process. The modified electrode was characterized by cyclic voltammetry and differential pulse voltammetry. It exhibited high sensitivity compared with unmodified electrode. Some experimental parameters which affected sensor response were optimized. Under optimum conditions and at a working voltage of typically -0.56 V (vs. Ag/AgCl), the sensor has a low detection limit (3 ng mL-1), a wide linear range (0.01-6 µg mL-1) and good long-term stability. The method was successfully applied to the sensitive and rapid determination of DNR in spiked human serum samples. Graphical abstract Platinum nanoparticles were loaded onto a nanocomposite prepared from nitrogen decorated reduced graphene oxide and single-walled carbon nanotubes (N-rGO-SWCNTs-Pt) and then used for electrochemical determination of daunorubicin (DNR).


Assuntos
Antineoplásicos/análise , Daunorrubicina/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotubos de Carbono/química , Platina/química , Antineoplásicos/sangue , Técnicas Biossensoriais/métodos , Daunorrubicina/sangue , Eletrodos , Humanos , Limite de Detecção , Nitrogênio/química , Oxirredução
11.
Mikrochim Acta ; 186(3): 177, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771082

RESUMO

An electrochemical sensor is described for the simultaneous determination of the pollutants catechol (CC) and hydroquinone (HQ). A glassy carbon electrode (GCE) was modified with reduced graphene oxide, Fe3O4 and gold nanoparticles and then showed a pair of well-defined voltammetric peaks for CC and HQ. Its oxidation peak potentials (located at 0.21 and 0.10 V vs. Ag/AgCl) are well separated, and this makes it suitable for simultaneous determination of the two isomers. Under optimal conditions, the oxidation peak currents of CC and HQ increase linearly in the 0.05-550 µM and 0.1-500 µM concentration ranges, even in the presence of 0.1 mM of the respective other isomer. The detection limits are 0.02 and 0.17 µM (at S/N = 3), respectively. The modified GCE exhibits good selectivity and recovery when applied for the analysis of spiked wastewater. Graphical abstract Ternary hybrid nanomaterials of rGO-Fe3O4-Au was developed for simultaneous electrochemical determination of catechol (CC) and hydroquinone (HQ).

12.
Int J Mol Sci ; 20(3)2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754638

RESUMO

Medicinal herbal plants have been commonly used for intervention in different diseases and improvement of health worldwide. Koumine, an alkaloid monomer found abundantly in Gelsemium plants, can be effectively used as an antioxidant. The purpose of this study was to evaluate the potential protective effect of koumine against hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis in porcine intestinal epithelial cell line (IPEC-J2 cells). MTT assays showed that koumine significantly increased cell viability in H2O2-mediated IPEC-J2 cells. Preincubation with koumine ameliorated H2O2-medicated apoptosis by decreasing reactive oxygen species (ROS) production, and efficiently suppressed the lactate dehydrogenase (LDH) release and malondialdehyde (MDA) production. Moreover, a loss of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) activities was restored to normal level in H2O2-induced IPEC-J2 cells upon koumine exposure. Furthermore, pretreatment with koumine suppressed H2O2-mediated loss of mitochondrial membrane potential, caspase-9 and caspase-3 activation, decrease of Bcl-2 expression and elevation of Bax expressions. Collectively, the results of this study indicated that koumine possesses the cytoprotective effects in IPEC-J2 cells during exposure to H2O2 by suppressing production of ROS, inhibiting the caspase-3 activity and influencing the expression of Bax and Bcl-2. Koumine could potentially serve as a protective effect against H2O2-induced apoptosis.


Assuntos
Antioxidantes/farmacologia , Gelsemium/química , Peróxido de Hidrogênio/farmacologia , Alcaloides Indólicos/farmacologia , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/farmacologia , Animais , Antioxidantes/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Alcaloides Indólicos/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Suínos
13.
Molecules ; 22(9)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28858253

RESUMO

Nanotechnology has become more and more potentially used in diagnosis or treatment of diseases. Advances in nanotechnology have led to new and improved nanomaterials in biomedical applications. Common nanomaterials applicable in biomedical applications include liposomes, polymeric micelles, graphene, carbon nanotubes, quantum dots, ferroferric oxide nanoparticles, gold nanoparticles (Au NPs), and so on. Among them, Au NPs have been considered as the most interesting nanomaterial because of its unique optical, electronic, sensing and biochemical properties. Au NPs have been potentially applied for medical imaging, drug delivery, and tumor therapy in the early detection, diagnosis, and treatment of diseases. This review focuses on some recent advances in the use of Au NPs as drug carriers for the intracellular delivery of therapeutics and as molecular nanoprobes for the detection and monitoring of target molecules.


Assuntos
Portadores de Fármacos/administração & dosagem , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Animais , Portadores de Fármacos/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Sondas Moleculares/administração & dosagem , Sondas Moleculares/química , Imagem Óptica , Coloração e Rotulagem
14.
Drug Chem Toxicol ; 37(1): 55-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23848144

RESUMO

Arsenic exists widely in rock, water and air, and arsanilic acid (also known as aminophenyl arsenic acid) is an organoarsenic compound and has been used as feed additives. Organoarsenic compounds in foodstuff cause adverse effects, including acute and chronic toxicity, in animals and humans. However, little is known about the cellular toxicity and mechanisms of organic arsenic on the kidney. In this study, we explored the toxicity and molecular mechanisms of arsanilic acid on rat kidney epithelial cells (NRK-52e cells). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that arsanilic acid inhibited the proliferation of rat NRK-52e cells in a dose-dependent manner, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and flow cytometry revealed that arsanilic acid induced cellular apoptosis in NRK-52e cells. Fluorescence spectrophotometer displayed that arsanilic acid caused a loss of mitochondrial transmembrane potential (MMP) of NRK-52e cells, but enhanced reactive oxygen species level of these cells. Notably, trolox, a water-soluble derivative of vitamin E, protected NRK-52e cells against MMP loss and apoptosis caused by arsanilic acid. Western blots with caspase inhibitors further indicated that arsanilic acid increased expression of active caspase-3 and -9 in NRK-52e cells. Collectively, these results suggest that arsanilic acid causes apoptosis and oxidative stress in rat kidney epithelial cells through activation of the caspase-9 and -3 signaling pathway. This study thus provides a novel insight into molecular mechanisms by which arsanilic acid has adverse cytotoxicity on renal tubular epithelial cells.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Arsanílico/toxicidade , Ativação Enzimática/efeitos dos fármacos , Células Epiteliais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Rim/citologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência , Sais de Tetrazólio , Tiazóis
15.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(12): 1487-91, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25632751

RESUMO

OBJECTIVE: To study the effect of Bushen Tongdu Capsule (BTC) on RANK/RANKL/ OPG pathway of collagen induced arthritis (CIA) rats, thereby laying theoretic evidence for treating rheumatic arthritis (RA) by Chinese medicine. METHODS: RA model was induced by CIA. Totally 42 rats were randomly divided into six groups, i.e., the normal control group, the model group, the low dose BTC (BSL) group, the medium dose BTC (BSM) group, the high dose BTC (BSH) group, and the Tripterygium Glycosides (TG) group, 7 in each group. BTC at the daily dose of 120, 240, and 480 mg/kg was given by gastrogavage to rats in the BSL, BSM, and BSH group respectively from the 13th day of modeling. TG at the daily dose of 24 mg/kg was given by gastrogavage to rats in the TG group. All medication was given once daily, 2 mL each time. Two mL normal saline was administered to rats in the normal control group and the model group. All medication lasted for 18 days. Samples were taken at day 31. The TRAP section of the ankle joint was fixed in 10% formalin for TRAP stain. Serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), and macrophage colony-stimulating factor (M-CSF) were detected using ELISA. RESULTS: Compared with the normal control group, positive reactions of pathological ankle joint section, inflammation, and osteoclasia degree were significantly improved in the model group, serum levels of RANKL and M-CSF were up-regulated, levels of OPG and OPG/RANKL were significantly lowered (all P < 0.01). Compared with the model group, positive reactions of pathological ankle joint section, inflammation, and osteoclasia degree also significantly decreased in the BSH group and the TG group (all P < 0.01). RANKL and M-CSF were significantly down-regulated in each medicated group, while levels of OPG and OPG/RANKL were significantly up-regulated (all P < 0.01). Compared with the TG group, M-CSF was lower, but levels of OPG and OPG/RANKL were significantly up-regulated in the normal control group (all P < 0.01). RANKL and M-CSF were significantly up-regulated, while levels of OPG and OPG/RANKL were significantly down-regulated in the model group and each BS group (all P < 0.01). CONCLUSION: BTC could relieve bone damage of CIA rats possibly through regulating and controlling osteoclasts.


Assuntos
Artrite Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Animais , Inflamação , Fator Estimulador de Colônias de Macrófagos/metabolismo , Osteoclastos , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Ratos , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Tripterygium
16.
Biosens Bioelectron ; 237: 115539, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487285

RESUMO

Constructing mono-luminophor-based electrochemiluminescence (ECL) ratio system is a great challenge due to the limitations of the luminescent species with dual-signal-output, luminescence efficiency and coreactant. This work developed carboxyl-functionalized poly[9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene]-alt-2,7-(9,9 dioctylfluorene)] nanoparticles(PFN NPs) as dual-emitting luminophors, which can synchronously output strong cathodic and anodic ECL signals without any exogenous coreactants. The inherent molecular structure enabled efficient intramolecular electron transfer between tertiary amine groups and backbone of PFN to generate strong cathodic and anodic ECL emission. Particularly, H+ in aqueous solution played an irreplaceable role for cathodic ECL emission. The silver nanoparticles (AgNPs) were developed as signal regulator because of their excellent hydrogen evolution reaction (HER) activity, which significantly quenched the cathodic signal while kept the anodic signal unchanged. The dual-emitting PFN NPs cleverly integrated signal regulator AgNPs and bicyclic strand displacement amplification (SDA) to construct a coreactant-free mono-luminophor-based ratiometric ECL sensing for SARS-CoV-2 RdRp gene assay. The strong dual-emitting of PFN NPs and excellent quenching effect of AgNPs on cathodic emission endowed the biosensor with a high detection sensitivity, and the detection limit was as low as 39 aM for RdRp gene. The unique dual-emitting properties of PFN NPs open up a new path to construct coreactant-free mono-luminophor-based ECL ratio platform, and excellent HER activity of AgNPs offers some new thoughts for realizing ECL signal changes.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Humanos , Polímeros/química , Nanopartículas Metálicas/química , SARS-CoV-2/genética , Medições Luminescentes , COVID-19/diagnóstico , Prata , RNA Polimerase Dependente de RNA , Técnicas Eletroquímicas
17.
Life (Basel) ; 13(4)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37109587

RESUMO

The ancient guanine nucleotide-binding (G) proteins are a group of critical regulatory and signal transduction proteins, widely involved in diverse cellular processes of all kingdoms of life. YchF is a kind of universally conserved novel unconventional G protein that appears to be crucial for growth and stress response in eukaryotes and bacteria. YchF is able to bind and hydrolyze both adenine nucleoside triphosphate (ATP) and guanosine nucleoside triphosphate (GTP), unlike other members of the P-loop GTPases. Hence, it can transduce signals and mediate multiple biological functions by using either ATP or GTP. YchF is not only a nucleotide-dependent translational factor associated with the ribosomal particles and proteasomal subunits, potentially bridging protein biosynthesis and degradation, but also sensitive to reactive oxygen species (ROS), probably recruiting many partner proteins in response to environmental stress. In this review, we summarize the latest insights into how YchF is associated with protein translation and ubiquitin-dependent protein degradation to regulate growth and maintain proteostasis under stress conditions.

18.
Talanta ; 265: 124877, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37385188

RESUMO

Benzoyl peroxide (BPO) is a commonly used flour whitener, but its excessive usage can have adverse effects on human health, such as nutrient loss, vitamin deficiencies and certain diseases. In this study, a europium metal organic framework (Eu-MOF) fluorescence probe was prepared, which exhibited a strong fluorescence emission at 614 nm upon excitation at 320 nm, with a high quantum yield of 8.11%. The red fluorescence of the probe could be effectively quenched by BPO through the inner filter effect (IFE) and photoinduced electron transfer (PET) mechanism. The detection process offered several advantages, including a wide linear range of 0-0.95 mM, a low detection limit of 66 nM and a fast fluorescence response of 2 min. Furthermore, an intelligent detection platform was designed to enhance the practical application of the detection method. This platform combined the portability and visuality of a traditional test strip with the color recognition capability of a smartphone, allowing for the visualization and quantitative detection of BPO in a convenient and user-friendly manner. The detection platform was successfully applied to the analysis of BPO in real flour samples with satisfactory recoveries (99.79%-103.94%), suggesting a promising strategy for the rapid and on-site detection of BPO in food samples.


Assuntos
Peróxido de Benzoíla , Farinha , Humanos , Peróxido de Benzoíla/análise , Farinha/análise , Smartphone , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes , Limite de Detecção
19.
Animals (Basel) ; 13(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37174491

RESUMO

The effects of dietary supplementation with two particle sizes of nano zinc oxide (ZnO) on growth performance, immune function, intestinal morphology, and the gut microbiome were determined in a 42-day broiler chicken feeding experiment. A total of 75 one-day-old Arbor Acres broilers were randomized and divided into three groups with five replicates of five chicks each, including the conventional ZnO group (NC), the nano-ZnO group with an average particle size of 82 nm (ZNPL), and the nano-ZnO group with an average particle size of 21 nm (ZNPS). Each group was supplemented with 40 mg/kg of ZnO or nano-ZnO. Our results revealed that birds in the ZNPS group had a higher average daily gain and a lower feed-to-gain ratio than those in the NC group. ZNPS significantly increased the thymus index and spleen index, as well as the levels of serum metallothionein (MT), superoxide dismutase (SOD), and lysozyme (LZM). The ZNPS treatments reduced interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α) levels and increased IL-2 and interferon (IFN)-γ levels compared to that in the NC group. Additionally, compared with the birds in the NC group, those in the nano-ZnO group had a higher villus height to crypt depth ratio of the duodenum, jejunum, and ileum. Bacteroides increased in the ZNPS group at the genus level. Further, unidentified_Lachnospiraceae, Blautia, Lachnoclostridium, unidentified_Erysipelotrichaceae, and Intestinimonas were significantly increased in the ZNPL group. In conclusion, nano-ZnO improved the growth performance, promoted the development of immune organs, increased nonspecific immunity, improved the villus height to crypt depth ratio of the small intestine, and enriched the abundance of beneficial bacteria. Notably, the smaller particle size (21 nm) of nano-ZnO exhibited a more potent effect.

20.
Plant Signal Behav ; 17(1): 2024405, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35135414

RESUMO

Guanine nucleotide-binding (G) proteins, namely, phosphate-binding (P) loop GTPases, play a critical role in life processes among different species. Based on the structural characteristics, G proteins can be divided into heterotrimeric G proteins, small G proteins and multiple unique unconventional G proteins. The highly conserved unconventional G protein YchF is composed of a core G domain, an inserted coiled-coil domain, and a TGS domain from the N-terminus to the C-terminus. In this review, we compared the structural characteristics of the G domain in rice OsYchF1 with those of Rattus norvegicus heterotrimeric G protein α-subunit and human small G protein Ras-related G protein C and analyzed the binding modes of these G proteins with GTP or ATP by performing molecular dynamics simulations. In summary, it will provide new insights into the enormous diversity of biological function of G proteins.


Assuntos
Proteínas Heterotriméricas de Ligação ao GTP , Proteínas Monoméricas de Ligação ao GTP , Oryza , Animais , Proteínas Heterotriméricas de Ligação ao GTP/genética , Nucleotídeos , Oryza/genética , Domínios Proteicos , Ratos
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