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1.
Int J Environ Health Res ; 34(3): 1410-1420, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37211801

RESUMO

To evaluate the association between ATP2B1 gene polymorphisms and skeletal fluorosis, a cross-sectional study was conducted. In China, 962 individuals were recruited, including 342 cases of skeletal fluorosis. Four TP2BA1 polymorphisms (rs2070759, rs12817819, rs17249754, and rs7136259) were analysed. The results suggested that rs17249754 and rs7136259 were associated with skeletal fluorosis. After controlling confounders, the protective effect of GG genotype in rs17249754 was apparent in individuals over 45 years old, female, with urine fluoride concentration below 1.6 mg/L, serum calcium above 2.25 mmol/L or serum phosphorus between 1.1 and 1.3. Heterozygote TC in rs7136259 increased the risk of skeletal fluorosis in subjects who are elderly, female, with urinary fluoride more than 1.6 mg/L, serum calcium more than 2.25 mmol/L and blood phosphorus between 1.1 and 1.3 mmol/L. Four loci were found to be tightly related by linkage disequilibrium analysis, and the frequency of distribution of haplotype GCGT was lower in the skeletal fluorosis group.


Assuntos
Doenças Ósseas Metabólicas , Fluorose Dentária , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Fluoretos , Haplótipos , Cálcio , Polimorfismo de Nucleotídeo Único , Estudos Transversais , Doenças Ósseas Metabólicas/genética , China/epidemiologia , Fósforo , Fluorose Dentária/epidemiologia , Fluorose Dentária/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124114, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38447441

RESUMO

A ratiometric luminescent probe was fabricated using adenosine monophosphate (AMP) as a bridging ligand and 3-carboxyphenylboronic acid (3-CPBA) as the sensitizer and functional ligand that allowed the probe to recognize hydrogen peroxide (H2O2). The probe was labeled AMP-Tb/3-CPBA. Adding H2O2 caused the nonluminescent 3-CPBA to be converted into 3-hydroxybenzoic acid, which strongly luminesces at 401 nm. This meant that adding H2O2 decreased the AMP-Tb/3-CPBA luminescence intensity at 544 nm and caused luminescence at 401 nm. The 401 and 544 nm luminescence intensity ratio (I401/I544) was strongly associated with the H2O2 concentration between 0.1 and 60.0 µM, and the detection limit was 0.23 µM. Dual emission reverse-change ratio luminescence sensing using the probe allowed environmental effects to be excluded and the assay to be very selective. We believe that the results pave the way for the development of new functionalized lanthanide coordination polymers for use in luminescence assays.


Assuntos
Polímeros , Térbio , Peróxido de Hidrogênio , Luminescência , Ligantes , Monofosfato de Adenosina
3.
Biol Trace Elem Res ; 200(3): 1418-1441, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34003450

RESUMO

Fluorosis is a major public health problem globally. The non-availability of specific treatment and the irreversible nature of dental and skeletal lesions poses a challenge in the management of fluorosis. Oxidative stress is known to be one of the most important mechanisms of fluoride toxicity. Fluoride promotes the accumulation of reactive oxygen species by inhibiting the activity of antioxidant enzymes, resulting in the excessive production of reactive oxygen species at the cellular level which further leads to activation of cell death processes such as apoptosis. Phytochemicals that act as antioxidants have the potential to protect cells from oxidative stress. Evidence confirms that clinical symptoms of fluorosis can be mitigated to some extent or prevented by long-term intake of antioxidants and plant products. The primary purpose of this review is to examine recent findings that focus on the amelioration of fluoride-induced oxidative stress and apoptosis by natural and synthetic phytochemicals and their molecular mechanisms of action.


Assuntos
Antioxidantes , Fluoretos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Fluoretos/toxicidade , Estresse Oxidativo , Compostos Fitoquímicos/farmacologia , Espécies Reativas de Oxigênio
4.
Ann Biomed Eng ; 47(12): 2402-2415, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31290038

RESUMO

This work combines a particle injection system with our proposed magnetic resonance navigation (MRN) sequence with the intention of validating MRN in a two-bifurcation phantom for endovascular treatment of hepatocellular carcinoma (HCC). A theoretical physical model used to calculate the most appropriate size of the magnetic drug-eluting bead (MDEB, 200 µm) aggregates was proposed. The aggregates were injected into the phantom by a dedicated particle injector while a trigger signal was automatically sent to the MRI to start MRN which consists of interleaved tracking and steering sequences. When the main branch of the phantom was parallel to B0, the aggregate distribution ratio in the (left-left, left-right, right-left and right-right divisions was obtained with results of 8, 68, 24 and 0% respectively at baseline (no MRN) and increased to 84%, 100, 84 and 92% (p < 0.001, p = 0.004, p < 0.001, p < 0.001) after implementing our MRN protocol. When the main branch was perpendicular to B0, the right-left branch, having the smallest baseline distribution rate of 0%, reached 80% (p < 0.001) after applying MRN. Moreover, the success rate of MRN was always more than 92% at the 1st bifurcation in the experiments above.


Assuntos
Carcinoma Hepatocelular/terapia , Embolização Terapêutica/instrumentação , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/instrumentação , Modelos Teóricos , Desenho de Equipamento , Humanos , Nanopartículas de Magnetita , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
5.
Chemosphere ; 199: 694-701, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29471239

RESUMO

The skeletal lesion of fluoride has become a major concern in many countries due to its damage to bone and joints and even leading to disability. Skeletal fluorosis is characterized by disturbance of bone metabolism, aberrant proliferation and activation of osteoblasts is critical for the pathogenesis. However, the mechanism underlying the osteotoxicity of fluoride has not been clearly illustrated and there is still limited information on the role of miRNAs in skeletal fluorosis. In this study, we found that NaF promoted SaoS2 proliferation and activation by activating BMP4/Smad pathway. NaF increased expression of miR-200c-3p and miR-200c-3p inhibitor reduced activation of SaoS2 induced by NaF via targeting Noggin to repress BMP4/Smad. These findings suggested an important regulatory role of miR-200c-3p on BMP4/Smad pathway during skeletal fluorosis. MiR-200c-3p might be a novel therapeutic target for skeletal fluorosis.


Assuntos
Fluoretos/farmacologia , MicroRNAs/fisiologia , Osteossarcoma/metabolismo , Proteína Morfogenética Óssea 4/efeitos dos fármacos , Proteína Morfogenética Óssea 4/metabolismo , Proteínas de Transporte , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fluoretos/metabolismo , Humanos , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteossarcoma/patologia , Fluoreto de Sódio/efeitos adversos , Fatores de Transcrição/metabolismo
6.
J Chromatogr A ; 1394: 95-102, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25843423

RESUMO

Liquid chromatography-electrospray ionization mass spectrometry has been applied to qualitative analysis of oligomeric phenylethoxysiloxanols, a class of organosilanols as active intermediates to polyhedral silsesquioxanes. The phenylethoxysiloxanol samples were prepared by controlled acid-catalyzed hydrolysis and condensation of phenyltriethoxysilane at various molar equivalents of water (r1) and characterized by standard spectroscopic techniques. Using a gradient binary water-methanol mobile phase, these reaction products were resolved on octadecylsiloxane silica stationary phase and subsequently identified by online electrospray ionization mass spectrometric detection. Results show that the reaction products are composed of a multitude of linear and monocyclic siloxanol oligomers with various numbers of silicon atoms and hydroxyl groups, depending upon the reaction conditions used. With the r1 value increasing from 0.5 to 2.0, the chain lengths of the oligomers increase slightly but the numbers of hydroxyl groups increase considerably, accompanying by structural evolution from chains to rings. Characterization of the retention behavior of these oligomers indicates that hydrophobic interactions of phenyl and ethoxy groups with the stationary phase are responsible for their retention in reversed-phase liquid chromatography.


Assuntos
Siloxanas/química , Cromatografia de Fase Reversa/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos
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