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1.
Environ Toxicol ; 38(4): 914-925, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36602389

RESUMO

The dibutyl phthalate (DBP) has been detected in fetuses and infants and can cause damage to the reproductive system in adulthood, but the exact mechanism remains unclear. Here, we aim to investigate the effects of intrauterine DBP exposure on offspring reproductive function and explore possible mechanisms. SPF C57BL/6 pregnant mice were given DBP (0.5, 5, 75 mg/kg/d) or corn oil from day 5 to day 19 by gavage. After weaning, the pups were fed a standard diet for 5 weeks. In addition, TM3 Leydig cell cultures were used to study the relevant mechanisms in vitro. The results showed that intrauterine DBP exposure could reduce sperm density and sperm motility, cause testicular tissue damage, down-regulate serum T and LH levels, and up-regulate serum FSH levels at 75 mg/kg/d. Western blot and methylation detection revealed intrauterine exposure to DBP down-regulated testosterone synthesis-related proteins StAR, P450scc, 3ß-HSD, PKA, and PKC expression, while up-regulated the levels of methyltransferase proteins expression and DNA 5-methylcytosine (5mC) in testicular tissue of mouse offspring at 75 mg/kg/d. Further detection found in utero 75 mg/kg/d DBP exposure down-regulated MGARP protein expression, and induced incomplete methylation of the MGARP gene. An in vitro analysis showed that MGARP inhibition is involved in an impaired testosterone synthesis in TM3 cells. Cell culture results suggest that MGARP down-regulation may be involved in impaired testosterone production in monobutyl phthalate-treated cells. The present study revealed that 75 mg/kg/d DBP exposure in utero resulted in testosterone synthesis disorders and reproductive function impairment in mouse offspring, and the mechanism may be related to DNA methylation-mediated down-regulation of MGARP in the testis.


Assuntos
Metilação de DNA , Dibutilftalato , Animais , Feminino , Masculino , Camundongos , Gravidez , Dibutilftalato/farmacologia , Camundongos Endogâmicos C57BL , Sêmen/metabolismo , Motilidade dos Espermatozoides , Testículo , Testosterona
2.
Environ Toxicol ; 36(5): 789-799, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33331133

RESUMO

With the aggravation of environmental pollution, the incidence of infertility is increasing. Ginsenoside Rg1 is a monomer component extracted from Panax ginseng. It has been found that Ginsenoside Rg1 is able to prevent premature ovarian failure and delay testicular senescence. Therefore, we speculate Ginsenoside Rg1 may have great potential to prevent and treat infertility. The aim of this work is to explore whether Ginsenoside Rg1 plays a protective role in the dinbutyl phthalate (DBP)-induced reproductive function injury mice, and to elucidate the potential mechanism. C57BL/6J male mice were administered by DBP with or without Ginsenoside Rg1 treatment and serum, testis and epididymis were collected for further analysis. Sperm analysis, hematoxylin and eosin staining, and serum hormone detection indicated that Ginsenoside Rg1 treatment improved the sperm density and sperm motility, reduced the testicular tissue damage, increased the serum testosterone and luteinizing hormone levels, and decreased the serum follicle-stimulating hormone level in DBP-induced mice. Furthermore, Ginsenoside Rg1 treatment upregulated expression levels of spermatogenesis-related protein, Cx43, E-cadherin, p-PI3K, p-Akt, and mTOR in the mice treated by DBP, observed by using a immunohistochemistry assay, a real-time quantitative PCR assay, and a western blot analysis. The present study reveals that Ginsenoside Rg1 may exert anti-DBP-induced reproductive function injury in C57BL/6J mice. In addition, the protect role of Ginsenoside Rg1 in spermatogenesis may be associated with the regulation of reproductive hormones, upregulation of spermatogenic associated proteins expression, restoration of the gap junctions, and the activation of PI3K/Akt/mTOR signaling pathways.


Assuntos
Ginsenosídeos , Fosfatidilinositol 3-Quinases , Animais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácidos Ftálicos , Motilidade dos Espermatozoides
3.
Int J Mol Sci ; 20(2)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654548

RESUMO

DnaJ proteins, which are molecular chaperones that are widely present in plants, can respond to various environmental stresses. At present, the function of DnaJ proteins was studied in many plant species, but only a few studies were conducted in tomato. Here, we examined the functions of a novel tomato (Solanum lycopersicum) DnaJ protein (SlDnaJ20) in heat tolerance using sense and antisense transgenic tomatoes. Transient conversion assays of Arabidopsis protoplasts showed that SlDnaJ20 was targeted to chloroplasts. Expression analysis showed that SlDnaJ20 expression was induced by chilling, NaCl, polyethylene glycol, and H2O2, especially via heat stress. Under heat stress, sense plants showed higher fresh weights, chlorophyll content, fluorescence (Fv/Fm), and D1 protein levels, and a lower accumulation of reactive oxygen species (ROS) than antisense plants. These results suggest that SlDnaJ20 overexpression can reduce the photoinhibition of photosystem II (PSII) by relieving ROS accumulation. Moreover, higher expression levels of HsfA1 and HsfB1 were observed under heat stress in sense plants, indicating that SlDnaJ20 overexpression contributes to HSF expression. The yeast two-hybrid system proved that SlDnaJ20 can interact with the chloroplast heat-shock protein 70. Our results indicate that SlDnaJ20 overexpression enhances the thermotolerance of transgenic tomatoes, whereas suppression of SlDnaJ20 increases the heat sensitivity of transgenic tomatoes.


Assuntos
Proteínas de Choque Térmico HSP40/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiologia , Termotolerância/fisiologia , Sequência de Aminoácidos , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico HSP40/química , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico/genética , Solanum lycopersicum/genética , Complexo de Proteína do Fotossistema II/metabolismo , Filogenia , Plantas Geneticamente Modificadas , Ligação Proteica , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
4.
Chemistry ; 21(18): 6898-905, 2015 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-25778105

RESUMO

Surface-mediated Schiff base coupling reactions between oligothiophenes equipped with an aldehyde group and aromatic diamines were investigated on highly oriented pyrolytic graphite (HOPG) by means of scanning tunneling microscopy (STM) under ambient conditions. To investigate the evolution process from monomers to resultant polymers and the mechanism of reactions, we controlled the ratio of precursors and the reactive temperature, and we obtained high-resolution STM images of different stages of the surface reaction. The results suggest that preferential adsorption of one kind of monomer has a great influence on the on-surface Schiff base reaction.

5.
Clin Pediatr (Phila) ; : 99228241245343, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606919

RESUMO

This research aimed to investigate the diagnostic value of passive particle agglutination test, Mycoplasma pneumoniae (MP) culture, cold agglutination test (CAT), enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction-capillary electrophoresis fragment analysis (PCR-CEFA) for MP infection. Children with respiratory tract infections suspected to be MP infection were subjected to passive particle agglutination test, MP culture, CAT, ELISA, and PCR-CEFA. A total of 146 children (81 males, 65 females, mean age: 5.74 ± 3.32 years, and mean course of disease: 9.07 ± 5.18 days) met the inclusion criteria. The positivity rate of MP detection by MP culture was 69.18% (101/146). Using the MP culture method as the standard, higher sensitivity and positive predictive value were found in the PCR-CEFA compared with the other 3 methods. Appropriate methods are selected following the advantages and disadvantages of pathogen detection, and pediatric MP infection is analyzed by integrating various test results.

6.
Chem Commun (Camb) ; 51(27): 5864-7, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25727408

RESUMO

We have designed and synthesized two porphyrin containing two-dimensional (2D) polymers based on the imine linkage. Both the 2D polymers are revealed to be 2D organic semiconductors with band gaps of around 1 eV. STM characterization reveals that the rigidity and affinity of building blocks to the surface has essential effects on the topology of the 2D polymers.

7.
Chem Asian J ; 9(7): 1888-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24839081

RESUMO

Tuning and characterizing the interfacial structure of organic semiconductors on graphene is essential for graphene-based devices. Regulation of the supramolecular assembling structure of oligothiophenes on graphene by changing functional groups attached to the backbone of oligothiophenes is described and the assembling behavior is compared with that on the basal plane of highly oriented pyrolytic graphite. It reveals that terminal functional groups attached to the conjugated backbone of oligothiophene can entirely change the assembling structures. Significant solvent and substrate effects have also been confirmed by comparing the assembling structures of oligothiophenes deposited from tetrahydrofuran, 1,2,4-trichlorobenzene, and octanoic acid onto graphene and graphite.


Assuntos
Grafite/química , Tiofenos/química , Caprilatos/química , Clorobenzenos , Furanos/química , Estrutura Molecular , Semicondutores , Solventes , Relação Estrutura-Atividade
8.
Chem Commun (Camb) ; 49(87): 10317-9, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24067842

RESUMO

On graphene grown on copper foil, oligothiophenes form identical supramolecular assemblies on different copper facets. Most importantly, we found that the graphene ripple structures, even with a height as small as ~0.5 nm, can significantly alter the molecule-substrate interaction, which has never been observed previously.


Assuntos
Cobre/química , Grafite/química , Tiofenos/química , Cristalização , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Volatilização
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