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1.
Vet Res ; 53(1): 104, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482404

RESUMO

The protective arm of the renin-angiotensin system (RAS), the ACE 2/Ang-(1-7)/MasR axis, has become a new anti-inflammatory target. As a specific activator of ACE2, diminazene aceturate (DA) can promote anti-inflammatory effects by regulating the ACE2/Ang-(1-7)/MasR axis. However, due to the reported toxicity of DA, its application has been limited. In the current study, we synthesized a low toxicity DA derivative 3 (DAD3) and sought to determine whether DAD3 can also activate ACE2 in bovine mammary epithelial cells (BMEC) and regulate the RAS system to inhibit inflammation. We found that both DA and DAD3 can activate and promote ACE2 expression in BMEC. iRNA-mediated knockdown of ACE2 demonstrated that DAD3 activates the ACE2/Ang-(1-7)/MasR axis and plays an anti-inflammatory role in BMEC. Furthermore, the inhibitory effects of DA and DAD3 on the protein phosphorylation of MAPK and NF-κB pathways were reduced in ACE2-silenced BMEC. Our findings show that ACE2 is a target of DAD3, which leads to inhibition of the MAPK and NF-κB signalling pathways and protects against LPS-induced inflammation in BMEC. Thus, DAD3 may provide a new strategy to treat dairy cow mastitis.


Assuntos
Células Epiteliais , NF-kappa B , Bovinos , Animais , Feminino , Anti-Inflamatórios/farmacologia
2.
J Dairy Sci ; 103(3): 2731-2742, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31954568

RESUMO

It was previously thought that the Panton-Valentine leukocidin (PVL) toxin of Staphylococcus aureus (S. aureus) was not the main cause of cow mastitis. However, in recent years, detection of the gene encoding PVL has been increasing in dairy cow mastitis, which implies that PVL may be related to bovine mastitis. Therefore, we wanted to search for drugs inhibiting PVL or PVL-induced apoptosis. In this report, we investigated the apoptosis mechanism of PVL in bovine mammary epithelial cells (BMEC) and the inhibition mechanism of matrine and baicalin on PVL-induced apoptosis of BMEC. The results demonstrated that BMEC were damaged and underwent apoptosis by a standard PVL-producing strain of S. aureus (ATCC 49775), a PVL knockout mutant Δpvl 49775, complemented mutant C-Δpvl 49775, or recombinant (r)PVL in vitro. The rates of apoptosis and necrosis induced by S. aureus ATCC 49775 and C-Δpvl 49775 were significantly higher than those induced by Δpvl 49775, demonstrating that BMEC apoptosis and necrosis were associated with PVL. In addition, this research found matrine and baicalin could inhibit the apoptosis of BMEC induced by PVL-producing S. aureus and by rPVL. Matrine downregulated protein expression levels of endogenous and exogenous cleaved caspase-3, cleaved caspase-8, and cleaved caspase-9, and the effect was pronounced at a concentration of 50 µg/mL. Baicalin downregulated the expression of cleaved caspase-9. These results suggested that matrine and baicalin may have potential value against cow mastitis caused by the toxin PVL.


Assuntos
Alcaloides/farmacologia , Apoptose , Toxinas Bacterianas/genética , Exotoxinas/genética , Flavonoides/farmacologia , Leucocidinas/genética , Mastite Bovina/microbiologia , Quinolizinas/farmacologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Animais , Bovinos , Células Epiteliais/efeitos dos fármacos , Feminino , Mutação , Infecções Estafilocócicas/microbiologia , Matrinas
3.
Artigo em Inglês | MEDLINE | ID: mdl-30230958

RESUMO

The initial emittable concentration, Cm,0, the material phase diffusion coefficient, Dm, and the air/material partition coefficient, K, are the key parameters used to predict the formaldehyde emissions from indoor building materials. This work presents formaldehyde emission experiments of plywood panels in a climatic chamber under various environmental conditions, which provides information on how relative humidity, temperature, and loading degree affect the formaldehyde emission. The experimental results showed that formaldehyde concentration in the climatic chamber increased rapidly during the initial 3 h, and then reached equilibrium after 7 h. The equilibrium concentration of formaldehyde in the closed chamber was increased by 1.1-1.3 times with the relative humidity increased by 20%, and 1.3-2.5 times with the temperature increased by 5 °C, respectively. In agreement with the experimental treatment, a new method of estimating parameters was carried out in a theoretical model from formaldehyde emission, opening the way to a factorial analysis of the relevant parameters for relative humidity and temperature. The theoretical model with estimated parameters was further validated by experiments with different environmental conditions, which should help to quickly determine the parameters needed to predict formaldehyde emissions.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Materiais de Construção/análise , Formaldeído/análise , Formaldeído/farmacocinética , Modelos Teóricos , Materiais de Construção/efeitos adversos , Difusão , Umidade , Teste de Materiais , Reprodutibilidade dos Testes , Estatística como Assunto , Temperatura
4.
J Air Waste Manag Assoc ; 64(1): 95-103, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24620407

RESUMO

UNLABELLED: Recovery of elemental sulfur from zinc concentrate direct leaching residue (DLR) using atmospheric distillation was systematically investigated on a pilot-scale system for the first time. Batch operating mode was suggested for recovery of elemental sulfur from water-rich DLR using atmospheric distillation. Elemental sulfur with purity higher than 99% was obtained under certain conditions in batch operating mode. With an appropriate feed amount of 1,200 kg, batch experiment conducted at 460 degrees C resulted in sulfur purity of 96.22% and a recovery rate higher than 85%. Only 0.59 and 1.24 kWh power was needed to handle 1.0 kg DLR and produce 1.0 kg elemental sulfur, respectively. The results suggest that recovery of elemental sulfur from zinc concentrate DLR using atmospheric distillation is technologically and economically feasible. Moreover, other metal elements such as zinc were enriched in the distillation concentrate, which could be used for metal refining. Technologies could effectively lower the moisture content of DLR, and lowering the distillation temperature would be of great value for recovery of elemental sulfur from DLR using a distillation method. IMPLICATIONS: Distillation is a promising solution for recovery of elemental sulfur from DLRs. This work revealed the possibility of separation of elemental sulfur from zinc concentrate DLR using atmospheric distillation. Such knowledge is of fundamental importance in developing field-scale separation and purification technologies and devices in which simultaneous sulfur recovery and precious metal enrichment are possible. Important tasks for follow-up research are also suggested.


Assuntos
Poluentes Atmosféricos/química , Enxofre/química , Zinco/química , Atmosfera , Resíduos Industriais , Microscopia Eletrônica de Varredura , Projetos Piloto
5.
Res Vet Sci ; 137: 102-110, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33964615

RESUMO

Diminazene aceturate (DA) has been used in the treatment of infections of trypanosomes in animals. Interestingly, its anti-inflammatory effect has recently gained increased interests. However, DA has been reported to have toxic side effects that limit its application. Therefore, we synthesized and screened a novel low-toxic DA derivative, namely the DA derivative 3 (DAD3). In the present study, anti-inflammatory effect of DAD3 was evaluated bovine mammary epithelial cells (BMECs) in vitro model. The results demonstrated that DAD3 had less cytotoxicity, and had a stronger effect in inhibiting secretion of inflammatory factors in BMECs, compared to DA. Mechanistically, DAD3 was able to inhibit the production of pro-inflammatory factors in part by suppressing the generation of mitochondrial reactive oxygen species (ROS) in BMECs upon LPS stimulation. Molecular analysis further indicated that DAD3 was capable of resolving inflammation in BMECs through a mechanism by preventing nuclear translocation of NF-p65, subsequently inhibiting transcription of inflammatory factors. In this context, DAD3 inhibited the phosphorylation of IκB, ERK, JNK and P-38 proteins of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. These results suggested the DAD3 was a novel DA derivative with low toxicity and strong anti-inflammatory effects in BMECs exposed to LPS, through a mechanism by blocking the NF-κB and MAPK signaling pathways. This study also provides an evidence that the DAD3 may be a novel anti-inflammatory agents warranted for further investigation in treatment of mastitis in cows.


Assuntos
Anti-Inflamatórios/uso terapêutico , Diminazena/análogos & derivados , Animais , Bovinos , Diminazena/uso terapêutico , Células Epiteliais/metabolismo , Feminino , Inflamação/tratamento farmacológico , Inflamação/veterinária , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Fosforilação
6.
Life Sci ; 256: 117852, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470448

RESUMO

AIMS: Atherosclerosis (AS) performs the important pathogenesis which refers to coronaryheart and vascular diseases. Long non-coding RNAs (lncRNAs) was reported to be related to the AS progression. We aimed to probe the role and potential mechanism of Myocardial Infarction Associated Transcript (MIAT) in AS. MATERIALS AND METHODS: Levels of MIAT, microRNA-148b (miR-148b) and pregnancy-associated plasma protein A (PAPPA) were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) in oxidized low-density lipoprotein (ox-LDL)-induced human aorta vascular smooth muscle cells (HA-VSMCs). Proliferation and migration were examined by Cell counting kit-8 (CCK-8) and wound-healing assays, respectively. Protein levels of Ki-67, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)-2, MMP-9 and PAPPA were examined by western blot assay. Ki-67 and PCNA level was detected by flow cytometry. The interaction among MIAT, miR-148b and PAPPA was confirmed via dual-luciferase reporter and RNA immunoprecipitation (RIP). The biology role of MIAT was detected by an AS model in vivo. KEY FINDINGS: The levels of MIAT and PAPPA were augmented, whereas mature miR-148b level was repressed in ox-LDL-induced AS model. The inhibitory effects of knockdown of MIAT on proliferation and migration were relieved by miR-148b inhibitor. Additionally, miR-148b regulated proliferation and migration by targeting PAPPA. Mechanically, MIAT functioned as sponge of miR-148b to impact PAPPA expression. MIAT knockdown protected AS mice against lipid metabolic disorders in vivo. SIGNIFICANCE: Proliferation and migration were modified by MIAT/miR-148b/PAPPA axis in ox-LDL induced AS cell model, supplying a novel insight into the underlying application of MIAT in the clinical treatment of AS.


Assuntos
Aterosclerose/patologia , MicroRNAs/genética , Proteína Plasmática A Associada à Gravidez/metabolismo , RNA Longo não Codificante/genética , Animais , Aterosclerose/genética , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Técnicas de Silenciamento de Genes , Humanos , Lipoproteínas LDL/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
7.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): m630, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21202184

RESUMO

In the title compound, [Cu(NCS)(2)(C(12)H(8)N(4)S)(2)(H(2)O)(2)]·2H(2)O, the Cu atom is located on an inversion center and displays an octa-hedral geometry. Two N atoms of two different 2,5-di-4-pyridyl-1,3,4-thia-diazole ligands and two N atoms from two separate thio-cyanate mol-ecules form the equatorial plane, while two coordinated water mol-ecules are in axial positions. The crystal structure is consolidated by extensive hydrogen bonding, forming a two-dimensional network.

8.
J Air Waste Manag Assoc ; 67(6): 713-724, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28121516

RESUMO

Activated carbons were prepared from tobacco stem by chemical activation using potassium hydroxide (KOH), potassium carbonate (K2CO3), and zinc chloride (ZnCl2). The effects of the impregnation ratio (activating agent/precursor) and activating agents on the physical and chemical properties of activated carbons were investigated. The textual structure and surface properties of activated carbons were characterized by nitrogen (N2) adsorption isotherm, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy (XPS), and thermogravimetry (TG). ZnCl2, acting as a superior activating agent compared to the others, produced much more porosity. The maximum specific surface area reached 1347 m2/g, obtained by ZnCl2 activation with an impregnation ratio of 4.0. Moreover, ZnCl2 activation yielded products with an excellent thermostability, attributed to different activation mechanisms. Various oxygen functions were detected on the activated carbon surface, and hydroxyl and ester groups were found to be in the majority. IMPLICATIONS: Tobacco stem, the residue from cigarette manufacturing, is usually discarded as waste, leading to serious resource waste and environmental problems. This study provides an effective utilization available for this solid residue by using it as the starting material in the preparation of activated carbon with chemical activation. Activated carbons with high specific area and various surface functions have been prepared, and the effects of the amount and type of activating agents on the physical and chemical properties of activated carbon were investigated as well.


Assuntos
Carbono/química , Nicotiana/química , Caules de Planta/química , Adsorção , Carbonatos , Carvão Vegetal/química , Cloretos , Hidróxidos , Nitrogênio/química , Espectroscopia Fotoeletrônica , Porosidade , Potássio , Compostos de Potássio , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Compostos de Zinco
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