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1.
Respir Res ; 20(1): 72, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30971247

RESUMO

BACKGROUND: Asthma exacerbations evoke emergency room visits, progressive loss of lung function and increased mortality. Environmental and industrial toxicants exacerbate asthma, although the underlying mechanisms are unknown. We assessed whether 3 distinct toxicants, salicylic acid (SA), toluene diisocyanate (TDI), and 1-chloro-2,4-dinitrobenzene (DNCB) induced airway hyperresponsiveness (AHR) through modulating excitation-contraction coupling in human airway smooth muscle (HASM) cells. The toxicants include a non-sensitizing irritant (SA), respiratory sensitizer (TDI) and dermal sensitizer (DNCB), respectively. We hypothesized that these toxicants induce AHR by modulating excitation-contraction (EC) coupling in airway smooth muscle (ASM) cells. METHODS: Carbachol-induced bronchoconstriction was measured in precision-cut human lung slices (hPCLS) following exposure to SA, TDI, DNCB or vehicle. Culture supernatants of hPCLS were screened for mediator release. In HASM cells treated with the toxicants, surrogate readouts of EC coupling were measured by phosphorylated myosin light chain (pMLC) and agonist-induced Ca2+ mobilization ([Ca2+]i). In addition, Nrf-2-dependent antioxidant response was determined by NAD(P) H quinone oxidoreductase 1 (NQO1) expression in HASM cells. RESULTS: In hPCLS, SA, but not TDI or DNCB, potentiated carbachol-induced bronchoconstriction. The toxicants had little effect on release of inflammatory mediators, including IL-6, IL-8 and eotaxin from hPCLS. In HASM cells, TDI amplified carbachol-induced MLC phosphorylation. The toxicants also had little effect on agonist-induced [Ca2+]i. CONCLUSION: SA, a non-sensitizing irritant, amplifies agonist-induced bronchoconstriction in hPCLS via mechanisms independent of inflammation and Ca2+ homeostasis in HASM cells. The sensitizers TDI and DNCB, had little effect on bronchoconstriction or inflammatory mediator release in hPCLS. IMPLICATIONS: Our findings suggest that non-sensitizing irritant salicylic acid may evoke AHR and exacerbate symptoms in susceptible individuals or in those with underlying lung disease.


Assuntos
Broncoconstrição/efeitos dos fármacos , Carbacol/toxicidade , Irritantes/toxicidade , Pulmão/efeitos dos fármacos , Ácido Salicílico/toxicidade , Broncoconstrição/fisiologia , Carbacol/administração & dosagem , Células Cultivadas , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Irritantes/administração & dosagem , Pulmão/metabolismo , Pulmão/patologia , Ácido Salicílico/administração & dosagem
2.
Artigo em Inglês | MEDLINE | ID: mdl-30601677

RESUMO

Noble metal nanoparticles (NPs) and their hybrids have demonstrated a strong potential to mimic the catalytic activity of natural enzymes and diminish oxidative stress. There is a large space to explore the intrinsic catalytic activity of Rh NPs with respect to reactive oxygen species (ROS) scavenging. We found that Rh NPs can quench H2O2, •OH, O2•-, 1O2 and inhibit lipid peroxidation under physiological conditions. In vitro cell experiments proved that Rh NPs have great biocompatibility and protect cells from oxidative damage caused by H2O2. This study can provide important insights that could inform future biological applications.


Assuntos
Materiais Biocompatíveis/análise , Peroxidação de Lipídeos , Nanopartículas Metálicas/análise , Espécies Reativas de Oxigênio/química , Ródio/análise , Catálise , Citotoxinas/química , Peróxido de Hidrogênio/química , Hidróxidos/química , Oxigênio Singlete/química
3.
Inorg Chem ; 58(19): 13360-13369, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31503468

RESUMO

The detection of hypochlorite (ClO-) content in tap water is extremely important because excess amounts of hypochlorite can convert into highly toxic species and inadequate amounts of hypochlorite cannot fully kill bacteria and viruses. Although several metal-organic frameworks (MOFs) have been successfully employed as fluorescent sensors for hypochlorite detection, all these sensors are based on single emission that responds to the dose of hypochlorite. Ratiometric sensors are highly desirable, which can improve the sensitivity, accuracy, and reliability via self-calibration. Herein, a nanoscale dual-emission multivariate 5-5-Eu/BPyDC@MOF-253-NH2 was synthesized by sequential mixed-ligand self-assembly and postsynthesis method. Among the two emission bands of 5-5-Eu/BPyDC@MOF-253-NH2, the strong blue emitting derived from ligands is sensitive to hypochlorite, while the red emitting derived from Eu(III) almost keeps invariable. Therefore, 5-5-Eu/BPyDC@MOF-253-NH2 was exploited as a fluorescent ratiometric nanosensor for "on-off" sensing of hypochlorite. Notably, the proposed sensing system showed an excellent performance including fast response (within 15 s), relative high specificity, wide linear range (0.1-30 µM), and low detection limit (0.094 µM). Besides, the suppressed blue emitting was recovered after the addition of ascorbic acid (AA) that consumes ClO- via the redox reaction. Therefore, 5-5-Eu/BPyDC@MOF-253-NH2 was further employed as a fluorescent ratiometric nanosensor for the "on-off-on" sensing of AA. This work represents the first MOF-based fluorescent "switch" for the ratiometric sensing of hypochlorite and the second for ratiometric sensing of AA.

4.
Artigo em Inglês | MEDLINE | ID: mdl-29115913

RESUMO

Research on noble metal nanoparticles (NPs) able to scavenge reactive oxygen species (ROS) has undergone a tremendous growth recently. However, the interactions between ruthenium nanoparticles (Ru NPs) and ROS have never been systematically explored thus far. This research focused on the decomposition of hydrogen peroxide (H2O2), scavenging of hydroxyl radicals (•OH), superoxide radical (O2•-), singlet oxygen (1O2), 2,2'-azino-bis(3-ethylbenzenothiazoline- 6-sulfonic acid ion (ABTS•+), and 1,1-diphenyl-2-picrylhydrazyl radical (•DPPH) in the presence of commercial Ru NPs using the electron spin resonance technique. In vitro cell studies demonstrated that Ru NPs have excellent biocompatibility and exert a cytoprotective effect against oxidative stress. These findings may spark fresh enthusiasm for the applications of Ru NPs under relevant physiologically conditions.


Assuntos
Sequestradores de Radicais Livres/química , Nanopartículas Metálicas/química , Modelos Químicos , Espécies Reativas de Oxigênio/química , Rutênio/química , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Oxigênio Singlete/química , Superóxidos/química
5.
Inorg Chem ; 55(11): 5671-83, 2016 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-27216949

RESUMO

Under hydrothermal conditions, six series of novel lanthanide (Ln) organogermanates (LnGs) [Ln8Ge12(µ3-O)24E12(H2O)16]·14H2O (Ln(3+) = Pr(3+), 1; Nd(3+), 2; Sm(3+), 3; Eu(3+), 4; Gd(3+), 5; one-dimensional (1-D) LnG cluster organic chain (LnGCOC)), {[Nd8Ge12(µ3-O)24E12(H2O)10](µ2-H2O)2[Nd8Ge12(µ3-O)24E12(H2O)16]}·18H2O (6, two-dimensional (2-D) planar LnG cluster organic layer (LnGCOL)), {[Ln2GeE(HO)2O(H2O)(CH3COO)2(CO3)]2[Ln8Ge12E12(µ3-O)24(H2O)10]}·6H2O (Ln(3+) = Pr(3+), 7; Nd(3+), 8; 2-D wave-shaped LnGCOL), [TbGeE(HO)2O(H2O)(pca)]2[Tb8Ge12E12(µ3-O)24(H2O)8]·10H2O (9, three-dimensional (3-D) LnG cluster organic framework (LnGCOF)), {([Nd(pza)2(H2O)2]2[Nd8Ge12E12(µ3-O)24(H2O)12])([Nd(pza)2]2[Nd8Ge12E12(Hpza)2(µ3-O)24(H2O)10])}·4OH·14H2O (10, 3-D LnGCOF), {[Nd8Ge12E12(µ3-O)24(H2O)10][Nd(pca)(pda)(H2O)]2}·12H2O (11, 3-D LnGCOF) and {[Nd8Ge12E12(µ3-O)24(H2O)10][Nd(pza)(pda)(H2O)]2}·12H2O (12, 3-D LnGCOF) (Hpca = 2-picolinic acid, H2pda = 2,6-pyridinedicarboxylic acid, Hpza = 2-pyrazinecarboxylic acid) were prepared by introducing the second auxiliary ligands into the organogermanate-lanthanide-oxide reaction system. The obtainment of these LnGs realized the utilization of the second auxiliary ligands inducing the assembly from 1-D LnGCOCs to 2-D LnGCOLs and 3-D LnGCOFs based on LnG cluster (LnGC) {Ln8Ge12E12(µ3-O)24(H2O)16}({Ln8Ge12}) units and Ln-organic complexes or organic ligand connectors. It should be noted that the well-organized structural constructions of 1-12 can be visualized as the gradual replacement of active water sites located at equatorial and polar positions on the hypothetical [Ln8Ge12(µ3-O)24E12(H2O)18] LnGC core with oxygen or nitrogen atoms from organic ligands. The solid-state luminescent properties of 2, 3, 4, 6, and 8-12 have been investigated at room temperature.

7.
DNA Cell Biol ; 43(7): 325-330, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38700464

RESUMO

Megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH), a type of overgrowth syndrome, is characterized by progressive megalencephaly, cortical brain malformations, and distal limb anomalies. Previous studies have revealed that the overactivity of the phosphatidylinositol 3-kinase-Protein kinase B pathway and the increased cyclin D2 (CCND2) expression were the main factors contributing to this disease. Here, we present the case of a patient who exhibited megalencephaly, polymicrogyria, abnormal neuronal migration, and developmental delay. Serum tandem mass spectrometry and chromosome examination did not detect any metabolic abnormalities or copy number variants. However, whole-exome sequencing and Sanger sequencing revealed a de novo nonsense mutation (NM_001759.3: c.829C>T; p.Gln277X) in the CCND2 gene of the patient. Bioinformatics analysis predicted that this mutation may disrupt the structure and surface charge of the CCND2 protein. This disruption could potentially prevent polyubiquitination of CCND2, leading to its resistance against degradation. Consequently, this could drive cell division and growth by altering the activity of key cell cycle regulatory nodes, ultimately contributing to the development of MPPH. This study not only presents a new case of MPPH and expands the mutation spectrum of CCND2 but also enhances our understanding of the mechanisms connecting CCND2 with overgrowth syndromes.


Assuntos
Ciclina D2 , Megalencefalia , Polidactilia , Polimicrogiria , Feminino , Humanos , Masculino , Códon sem Sentido/genética , Ciclina D2/genética , Sequenciamento do Exoma , Hidrocefalia , Malformações do Desenvolvimento Cortical , Megalencefalia/genética , Megalencefalia/diagnóstico , Polidactilia/genética , Polidactilia/diagnóstico , Polimicrogiria/genética , Polimicrogiria/diagnóstico , Pré-Escolar
8.
Front Neurol ; 15: 1319962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481944

RESUMO

This report presents a case of Charcot-Marie-Tooth dominant intermediate D (CMTDID), a rare subtype of Charcot-Marie-Tooth disease, in a 52 years-old male patient. The patient exhibited mobility impairment, foot abnormalities (pes cavus), and calf muscle atrophy. Whole exome sequencing and Sanger sequencing suggested that a novel variant (NM_000530.8, c.145C>A/p.His49Asn) of MPZ may be the genetic lesion in the patient. The bioinformatic program predicted that the new variant (p.His49Asn), located at an evolutionarily conserved site of MPZ, was neutral. Our study expands the variant spectrum of MPZ and the number of identified CMTDID patients, contributing to a better understanding of the relationship between MPZ and CMTDID.

9.
J Clin Hypertens (Greenwich) ; 26(7): 789-796, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38715256

RESUMO

An increased risk of target organ damage (TOD) has been reported in patients with primary aldosteronism (PA). However, there is relatively little related research on the correlation between the degree of TOD and those with and without PA in newly diagnosed hypertensive patients. The aim of this study was to assess the association between PA and TOD among patients with newly diagnosed hypertension. Newly diagnosed hypertensive patients were consecutively recruited from January 2015 to June 2020 at the University of Hong Kong-Shenzhen Hospital. Patients were stratified into those with and without PA. Data for left ventricular mass index (LVMI), carotid intima-media thickness (CIMT) and plaque, and microalbuminuria were systematically collected. A total of 1044 patients with newly diagnosed hypertension were recruited, 57 (5.5%) of whom were diagnosed with PA. Patients with PA had lower blood pressure, serum lipids, body mass index, and plasma renin activity and a higher incidence of hypokalemia than those without PA. In contrast, the prevalence of left ventricular hypertrophy, increased CIMT, and microalbuminuria was higher in patients with PA than in those without PA. Multivariable regression analysis demonstrated that PA was independently associated with increased LVMI, CIMT and microalbuminuria. Among patients with newly diagnosed hypertension, those with PA had more severe TOD, including a higher LVMI, CIMT and microalbuminuria, than those without PA. These findings emphasize the need for screening TOD in newly diagnosed hypertension due to underlying PA.


Assuntos
Albuminúria , Espessura Intima-Media Carotídea , Hiperaldosteronismo , Hipertensão , Hipertrofia Ventricular Esquerda , Humanos , Hiperaldosteronismo/complicações , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/epidemiologia , Feminino , Masculino , Hipertensão/epidemiologia , Hipertensão/complicações , Pessoa de Meia-Idade , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/diagnóstico , Hipertrofia Ventricular Esquerda/fisiopatologia , Albuminúria/epidemiologia , Albuminúria/etiologia , Albuminúria/diagnóstico , Prevalência , Adulto , Fatores de Risco , Pressão Sanguínea/fisiologia , Hong Kong/epidemiologia , Idoso , Hipopotassemia/epidemiologia , Hipopotassemia/etiologia , Hipopotassemia/diagnóstico
10.
Acta Crystallogr C ; 69(Pt 7): 712-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23832027

RESUMO

A new 3d-4f heterometallic polymer, poly[[aqua-µ3-chlorido-[µ3-4-(pyridin-4-yl)benzoato]tris[µ2-4-(pyridin-4-yl)benzoato]dicopper(I)erbium(III)] dihydrate], {[Cu2Er(C12H8NO2)4Cl(H2O)]·2H2O}n, was synthesized by the hydrothermal reaction of Er2O3, CuCl2·2H2O and 4-(pyridin-4-yl)benzoic acid in the presence of HClO4. The asymmetric unit contains one Er(3+) cation, two Cu(+) cations, one Cl(-) anion, four deprotonated 4-(pyridin-4-yl)benzoate ligands, one coordinated aqua ligand and two solvent water molecules. This tubular one-dimensional polymer is constructed from alternating clusters of europium(III)-water and copper(I) chloride bridged by 4-(pyridin-4-yl)benzoate ligands. Extensive hydrogen-bonding interactions involving both the coordinated and the solvent water molecules provide further stabilization to the structure.


Assuntos
Benzoatos/química , Cobre/química , Európio/química , Compostos Organometálicos , Polímeros/química , Piridinas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Água/química
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