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1.
Chemosphere ; 355: 141876, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570043

RESUMO

Gestodene (GES) is widely used in human therapy and animal husbandry and is frequently detected in aquatic environments. Although GES adversely affects aquatic organisms at trace levels, its effects on the reproductive biology of fish remain inconclusive. In this study, female zebrafish (Danio rerio) were exposed to environmentally relevant levels of GES for the evaluation of the effects of GES on the reproductive system by using endpoints including gene expression, plasma steroid concentrations, histological and morphological analyses, copulatory behavior, and reproductive output. Adult female zebrafish exposed to environmentally relevant concentrations of GES (4.0, 40.2, and 372.7 ng/L) for 60 d demonstrated stagnant ovarian oocyte development, evidenced by an increase in the percentage of perinuclear and atretic oocytes and a decrease in the percentage of late vitellogenic oocytes. GES-exposed females were less attractive to males and had lower copulatory intimacy than females in control. Consequently, spawning (44.3-49.2 %) and egg fertilization rates (27.9-32.0 %) were decreased. The decreased survival of fertilized eggs and hatching rates were accompanied by increased malformations. These negative effects were associated with abnormal transcriptional levels of gonadal steroid hormones, which were regulated by genes (Hsd17ß3, Hsd11ß2, Hsd20ß, Cyp19a1a, and Cyp11b). Overall, our findings suggest that GES impairs the reproductive system of zebrafish, which may threaten population stability.


Assuntos
Norpregnenos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Masculino , Humanos , Feminino , Peixe-Zebra/metabolismo , Ovário , Hormônios Esteroides Gonadais/metabolismo , Reprodução , Poluentes Químicos da Água/metabolismo , Gônadas
2.
Ecotoxicol Environ Saf ; 267: 115630, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37890255

RESUMO

Progestins are mainly used in pharmacotherapy and animal husbandry and have received increasing attention as they are widely detected in various aquatic ecosystems. In this study, adult female western mosquitofish (Gambusia affinis) were exposed to different concentrations of norethindrone (NET) (solvent control, 5.0 (L), 50.0 (M), and 500.0 (H) ng/L) for 42 days. Behaviors, morphological parameters, histology of the thyroid, thyroid hormone levels (TSH, T3, and T4), and transcriptional levels of nine genes in the hypothalamic-pituitary-thyroid (HPT) axis were examined. The results showed that NET decreased sociality but increased the anxiety of G. affinis. Sociality makes fish tend to cluster, and anxiety may cause G. affinis to reduce exploration of new environments. Female fish showed hyperplasia, hypertrophy, and glial depletion in their thyroid follicular epithelial cells after NET treatment. The plasma levels of TSH and T4 were significantly reduced, but T3 concentrations were significantly increased in the fish from the H group. In addition, the transcripts of genes (tshb, tshr, tg, dio1, dio2, thrb) in the brains of fish in the M and H treatments were significantly stimulated, while those of trh and pax2a were suppressed. Our results suggest that NET may impact key social behaviors in G. affinis and interfere with the entire thyroid endocrine system, probably via affecting the transcriptional expression of upstream regulators in the HPT axis.


Assuntos
Ciprinodontiformes , Glândula Tireoide , Feminino , Animais , Noretindrona , Ecossistema , Ciprinodontiformes/genética , Tireotropina
3.
Med Sci Monit ; 21: 2094-9, 2015 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-26190179

RESUMO

BACKGROUND: Type 2 diabetes (DMT2) combined with ischemic heart disease (IHD) promotes the occurrence and development of coronary atherosclerosis. We aimed to provide a theoretical basis for improving patient prognosis through analyzing expression of plasma brain natriuretic peptide (BNP), endothelin-1 (ET 1), and matrix metalloproteinase 9 (MMP-9). MATERIAL AND METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to detect BNP, ET-1, and MMP-9 levels in 50 patients with DMT2 only (group A), 47 patients with IHD only (group B), 43 patients with comorbid (both) IHD and DMT2 (group C), and 50 health controls (group D). Group C was further divided into single-branch lesion group, double-branch lesions group, and triple-branch lesion group according to coronary angiography, or cardiac function grade II, III, and IV group according to cardiac function, and their BNP, ET-1, and MMP-9 levels were compared. RESULTS: Compared with group D, TG, diastolic, and systolic blood pressure were all significantly elevated in groups A, B, and C. Group C exhibited obviously higher glycosylated hemoglobin than group A. Gensini score in group C was markedly higher than in group B. Compared with group D, BNP, ET-1, and MMP-9 levels were all increased in groups A, B, and C. Group C showed higher levels of BNP, ET-1, and MMP-9 than group A and B. BNP, ET-1, and MMP-9 levels in the triple-branch lesions group were higher than in the single-branch lesions group and double-branch lesions group. The cardiac function grade IV group presented higher levels of BNP, ET-1, and MMP-9 than did the grade II and III groups. BNP, ET-1, and MMP-9 showed a positive correlation to each other. CONCLUSIONS: BNP, ET-1, and MMP-9 may participate in the occurrence and development of comorbid DMT2 and IHD. They are important objective indicators for evaluating severity and prognosis of patients with comorbid DMA2 and IHD.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Endotelina-1/sangue , Metaloproteinase 9 da Matriz/sangue , Isquemia Miocárdica/sangue , Peptídeo Natriurético Encefálico/sangue , Adulto , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Diabetes Mellitus Tipo 2/complicações , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Prognóstico
4.
ScientificWorldJournal ; 2014: 653247, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24883420

RESUMO

The seismic behavior and plasticity spreading of a neotype column-slab high pier are researched in this paper. Four scale model tests of a web slab with two boundary columns are carried out under cyclic inelastic lateral displacements simulating seismic response. The test results show that the neotype column-slab high pier has strong and stable bearing capacity, good ductility, and energy dissipation capacity. The experimental values pertaining to the spread of plasticity are derived. An approach for deriving the spread of plasticity analytically is deduced and applied to the four tests. This method accurately assesses a pier's spread of plasticity for most ductility levels. At nearly all ductility levels, the mean difference between analytical assessments of the spread of plasticity and results from 4 large-scale tests is 12% with a 9% coefficient of variation.


Assuntos
Desastres , Terremotos , Colapso Estrutural , Teste de Materiais , Fenômenos Mecânicos , Colapso Estrutural/prevenção & controle , Resistência à Tração
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