Search

Amphibians undergo a metamorphic developmental process primarily regulated by thyroid hormone (TH), exhibiting dramatic changes in external morphology and internal tissues and organs and even in the expression of TH target genes, providing an ideal model for studying and testing thyroid disruptors. Since 2009, the Organization for Economic Cooperation and Development (OECD) has successively released three testing guidelines for thyroid disruptors based on amphibians, namely the amphibian metamorphosis assay (AMA, TG 231), the larval amphibian growth and development assay (LAGDA, TG 241), and the Xenopus eleutheroembryo thyroid assay (XETA, TG 248). These three assays are currently incorporated into The OECD Conceptual Framework for Testing and Assessment of Endocrine Disrupting Chemicals for screening and testing thyroid disruptors. Compared to AMA and LAGDA, which are based on spontaneous metamorphosis, Chinese researchers have developed the T3-induced Xenopus metamorphosis assay (TiXMA) for screening thyroid disruptors. To promote the understanding and application of these assays, this paper reviews the principles, endpoints, result interpretation, and the current application status of each assay, preliminarily compares their sensitivity and specificity for thyroid disruptors. It emphasized the need to validate these assays through testing more chemicals. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Although thyroid diseases are rarely thought to be related to tendon diseases and tendon tears, increasing evidence has indicated that thyroid diseases are involved in idiopathic tendon diseases in recent years. However, there are few studies on the effects of thyroid function on the development and mechanical properties of Achilles tendon during growth and development. OBJECTIVE: To clarify the correlation between thyroid hormone receptor beta (Thrβ) and thyroid hormone responsive (Thrsp) related to thyroid function and the mechanical properties and histological morphology of the Achilles tendon and to confirm the potential influence of thyroid function on the development of the Achilles tendon. METHODS: The expression profiles of developmental genes in Achilles tendon were analyzed by bioinformatics, and Thrβ and Thrsp genes related to thyroid function were identified. Then the mechanical properties of the Achilles tendon of female Sprague-Dawley rats at different growth and development stages (28, 42, 56 and 70 days of age, 6 females at each stage) were measured in a tensile test. Hematoxylin-eosin staining combined with histomorphometry was used for histological evaluation and the expression levels of Thrβ and Thrsp genes were determined by fluorescence quantitative PCR. Finally, correlation analysis was conducted to determine the relationship between Thrβ and Thrsp gene expression levels and mechanical properties and histological morphology of the Achilles tendon. RESULTS AND CONCLUSION: With the growth and development of rats, the maximum load, maximum tensile length and stiffness of the Achilles tendon did not change significantly after peaking. These mechanical properties of Achilles tendon may be related to the content, type and arrangement of collagen fibers in the tissue. Thrβ and Thrsp gene expression in the Achilles tendon at different growth stages were significantly correlated with the mechanical properties and histological scores of the Achilles tendon. These findings suggest that thyroid hormone plays a potential role in the development of the Achilles tendon and it is expected to offer new therapeutic ideas for the repair of Achilles tendon injury. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression and clinical significance of serum cysteine rich 61(CYR61) and Fractalkine in patients with Graves' Disease (GD). Methods: A total of 57 GD patients admitted to Handan Central Hospital of Hebei Province from March 2018 to October 2021 were selected as the research group. Another 50 healthy subjects were selected during the same period. Venous blood was collected from all subjects to detect serum CYR61, Fractalkine levels, thyroid function and thyroid autoantibody related indicators. Pearson test was used to analyze the correlation of serum CYR61 and Fractalkine levels with thyroid function and thyroid autoantibody related indicators in GD patients. Results: The serum CYR61 and Fractalkine levels in the study group were higher than those in the control group, and the differences were statistically significant (all P<0.05). Serum free triiodothyronine 3 (FT3) and free tetriodothyronine 4 (FT4) in the study group were higher than those in the control group, while the thyroid stimulating hormone (TSH) level was lower than that in the control group, the differences were statistically significant (all P<0.05). The anti-thyroglobulin antibody (TGAb), thyroid peroxidase antibody (TPOAb) and thyroid stimulating hormone receptor antibody (TRAb) levels in the study group were higher than those in the control group, and the differences were statistically significant (all P<0.05). Pearson correlation analysis showed that serum CYR61 and Fractalkine levels were positively correlated with the FT3, FT4, TGAb, TPOAb and TRAb levels in patients with GD, while negatively correlated with the serum TSH level (all P<0.05). Conclusion: Serum CYR61 and Fractalkine levels are abnormally high in patients with GD, which are related to thyroid function and thyroid autoantibodies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cold stress of livestock easily occurs in open sheds of cold areas during winter, due mainly to the relatively low thermal insulation under the low temperature conditions. As such, cold drinking water can further deteriorate the health and growth of young livestock. The objective of this study was to investigate the effect of drinking warm water in winter on the health and growth performance of weaned rabbits. A total of 180 weaned rabbits (47 days of age) with similar body weight (initial body weight 1.2±0.1 kg) were randomly assigned to two groups, either warm water (WW) or cold water (CW) (90 rabbits in each group). An electrical heating wire was also used to heat the warm water, where the water pipe was covered with insulated foam coating. A thermostatic controller was selected to remain at a constant temperature (35.5 ± 1.1 ◦C) during the experiment. The cold water was prepared at (5.8 ± 2.3)◦C without heating. A 48-day test was carried out to measure various indicators. The results showed that: 1) The indoor average air temperature was (8.9±3.2)℃ during the experiment. The average daily weight gain of rabbits in warm water group was significantly higher than that in cold water group during 47-58 days and 47-94 days, respectively, by 15.11 kg/d and 1.94 kg/d (P<0.05).. 2) The feed-weight ratio of rabbits was significantly lower in the warm water group than that in the cold water group during 47～58 days (18.2%) (P < 0.05). But there was no significant difference during the rest. In addition, the risk of diarrhea in rabbits drinking warm water was significantly reduced by 25.6% during 47～94 days (P < 0.05), compared with the cold water group. The expressions of thyroid hormone receptor α and β (THR α and β) in jejunum were significantly down-regulated on 70 days in rabbits drinking warm water (P < 0.05). 3) The contents of immunoglobulin A (IgA) and total protein (TP) in serum increased significantly for the rabbits drinking warm water, with the increase of age, especially on 82 days (P < 0.05). Moreover, the abundance of Roseburia increased in the cecum of rabbits on 82 days in the warm water group, relating to nutrient digestion and absorption, indicating 6.9 times higher than that of 58-day old rabbits (P < 0.05). Consequently, the constant temperature drinking system in the open sheds in winter can be expected to improve the immunity, intestinal digestion, and absorption capacity, thereby promoting the growth and health of weaned rabbits. The finding can provide theoretical support to improve the survival rate and production efficiency of weaned rabbits in open houses in cold areas. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: This study in order to use report gene assay based on the thyroid hormone receptor (TR) α/β from human origin for screening endocrine disruptors chemicals (EDCs), evaluating the thyroid hormone activity of Bisphenol (BPA), 1-Naphthaleny methyl carbamate and 1-naphthol (1-NAP)., Methods: Using Rhesus monkey kidney cells (LLC-MK2) as transfection cell to establish the gene report assay system based on pGL-3-promega and pGL4.27 of TRα/β through the method of transient transfection. Using T3 and T4 as positive subjects to evaluation the effectiveness of two detection systems and detect the thyroid hormone activity of BPA, 1-Naphthaleny methyl carbamate, 1-NAP., Results: The TRβ LLC-MK2 report gene assay based on pGL3-promega, the minimum detectable limit of T3 is 1.216×10 -11 mol/L, the largest induction multiple was shown at 7.482×10 -6 mol/L, the expression multiple of induced Lucifrerase was 5.98-fold that of the vehicle control, the EC 50 was 3.327×10 -8 mol/L; The minimum detectable limit of T4 was 1.622×10 -8 mol/L, the largest induction Luc expression was 3.4-fold of vehicle control, the EC 50 was 2.213×10 -7 mol/L. The TRβ LLC-MK2 report gene assay based on pGL4.27, the minimum detectable limit of T3 was 9.863×10 -12 mol/L, the largest induction Luc expression as shown at 1.671×10 -6 mol/L, resulting in 8.57-fold of vehicle control, the EC 50 is 3.327×10 -8 mol/L. The minimum detectable limit of T4 was 1.349×10 -9 mol/L, the largest induction Luc expression was 4.6-fold of vehicle control, the EC 50 is 4.074×10 -7 mol/L. There was no thyroid hormone activity by using TRβ report gene assay to evaluate BPA, 1-Naphthaleny methyl carbamate or 1-NAP, but 1-Naphthaleny methyl carbamate and 1-NAP have some degree receptor antagonism., Conclusions: The TRβ LLC-MK2 report gene assay based on pGL3- promega and pGL4.27 show highly sensitive (pGL4.27 relatively higher), can be used to screen for EDCS and test chemical thyroid hormone activity effectively., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Science Edition).)