Androgen Receptor Plays a Vital Role in Benomyl- or Carbendazim-Induced Reproductive and Developmental Toxicity and Endocrine-Disrupting Activity in Rats

Benomyl and its metabolite carbendazim were reported to induce reproductive and developmental toxicity and endocrine-disrupting activity in rats. The exactly underlying mechanism of reproductive and developmental toxicity and endocrine-disrupting activity still remain unclear. Based on our unpublished data it showed that the antiandrogen flutamide can completely recover the reproductive and developmental toxicity including embryolethality induced by benomyl and carbendazim in rats. This manuscript aimed to review and generalize the results based on our previous reports. Androgen receptor might play an important role in benomyl- and carbendazim-induced reproductive and developmental toxicity and endocrine-disrupting activity. The evidences were (1) androgen- and androgen receptor-dependent mechanisms are possibly involved in carbendazim-induced toxicity; (2) carbendazim exposure in utero displays a transient and weak androgenic effect and reduces flutamide antiandrogenicity in male rats; (3) antagonistic effect of flutamide on the carbendazim-androgenic effect on mRNA and protein levels; (4) benomyl and carbendazim exhibit an androgenic effect, leading to increase weight of ventral prostate and seminal vesicles and uterine fluid retention in young adult rats. The molecular underlying mechanism of reproductive and developmental toxicity and endocrine-disrupting activity induced by benomyl and carbendazim through androgen receptor need to be further investigated

The Pragmatic Strategy to Detect Endocrine-Disrupting Activity of Xenobiotics in Food

Endocrine-disrupting activity induced by xenobiotics might pose a possible health threat. Facing so many chemicals, there is an issue on how we detect them precisely and effectively. The whole embryo culture (WEC) test, an ex vivo exposure lasting 48 hours with rat embryos of 10.5 days old, is used to detect prenatal developmental toxicity. We extended the WEC function to detect the endocrine-disrupting activity induced by environmental chemicals. Results showed that in the development of rat embryo, basically 17ß-estradiol, triiodothyronine, triadimefon, penconazole, and propiconazole exhibited no significant effect on yolk sac circulatory system, allantois, flexion, heart caudal neural tube, hindbrain, midbrain, forebrain, otic system, optic system, olfactory system, maxillary process, forelimb, hind limb, yolk sac diameter, crown-rump length, head length, and developmental score. In the immunohistochemistry, the positive control of 17ß-estradiol showed positive effect for its receptor expressions. These three triazoles induced expressions of ERα and ERß in WEC. This result basically meets the mode of action that triazoles were designed to disrupt the synthesis of steroid hormone. Here we gave a strategy to detect possible endocrine-disrupting activity induced by xenobiotics in food. This strategy is quick to initiate the whole rat embryo culture with 10.5 days to detect the hormone receptors such as androgen, estrogen, thyroid, aromatase activity and its related receptors

Deltamethrin Alters Thyroid Hormones and Delays Pubertal Development in Male and Female Rats

Pyrethroid insecticides are suspected endocrine-disrupting chemicals. Deltamethrin has been reported to antagonize thyroid hormone receptor activity in a reporter assay. We hypothesized that deltamethrin alters thyroid function. Male and female rats were administered daily oral gavages with 0, 0.3, 1, or 3 mg/kg/day deltamethrin on postnatal days 23–53 and 22–42, respectively. Results showed that deltamethrin decreased the relative thyroid weight in 0.3 and 1 mg/kg/day in female but not in male rats. Although the histology and several parameters of thyroid were not affected, the decreased relative weight exhibited underlying meaning. Deltamethrin delayed the age of vaginal opening (VO) and increased body weight upon VO in 3 mg/kg/day. Deltamethrin failed to delay the age of preputial separation in male rats. In the respective of serum hormone concentration, deltamethrin increased 17β-estradiol (E2) with dose-dependent manner in female rats. The novel finding is that deltamethrin decreased thyroxine (T4), triiodothyronine (T3), and thyroid-stimulating hormone (TSH) in the female rats. In contrast, deltamethrin increased T3 and TSH but not in T4 in male rats. We inferred that deltamethrin disrupts thyroid hormone and might be related to estrogen receptor agonist. The future work is to investigate if deltamethrin disrupts the hypothalamus-pituitary-thyroid axis

Genetic variations of the porcine PRKAG3 gene in Chinese indigenous pig breeds

Four missense substitutions (T30N, G52S, V199I and R200Q) in the porcine PRKAG3 gene were considered as the likely candidate loci affecting meat quality. In this study, the R200Q substitution was investigated in a sample of 62 individuals from Hampshire, Chinese Min and Erhualian pigs, and the genetic variations of T30N, G52S and V199I substitutions were detected in 1505 individuals from 21 Chinese indigenous breeds, 5 Western commercial pig breeds, and the wild pig. Allele 200R was fixed in Chinese Min and Erhualian pigs. Haplotypes II-QQ and IV-QQ were not observed in the Hampshire population, supporting the hypothesis that allele 200Q is tightly linked with allele 199V. Significant differences in allele frequencies of the three substitutions (T30N, G52S and V199I) between Chinese indigenous pigs and Western commercial pigs were observed. Obvious high frequencies of the "favorable" alleles 30T and 52G in terms of meat quality were detected in Chinese indigenous pigs, which are well known for high meat quality. However, the frequency of the "favorable" allele 199I, which was reported to have a greater effect on meat quality in comparison with 30T and 52G, was very low in all of the Chinese indigenous pigs except for the Min pig. The reasons accounting for this discrepancy remain to be addressed. The presence of the three substitutions in purebred Chinese Tibetan pigs indicates that the three substitutions were ancestral mutations. A novel A/G substitution at position 51 in exon 1 was identified. The results suggest that further studies are required to investigate the associations of these substitutions in the PRKAG3 gene with meat quality of Chinese indigenous pigs, and to uncover other polymorphisms in the PRKAG3 gene with potential effects on meat quality in Chinese indigenous pigs

Postweaning Isolation Rearing Alters the Adult Social, Sexual Preference and Mating Behaviors of Male CD-1 Mice

Objective: No study has comprehensively evaluated the effect of postweaning isolation on the social and sexual behaviors of a certain strain of rodents in ethology. The present study aims to explore how and to what extent isolation rearing after postweaning affects the social and sexual behaviors of male CD-1 mice in adulthood systematically.Methods: Male CD-1 mice were randomly assigned to two groups: isolation reared (IS, one mouse per cage, n = 30) and group housed (GH, five mice per cage, n = 15). The mice underwent isolation rearing from postnatal day 23 to day 93. Then, social affiliation, recognition and memory were measured through selection task experiments. Social interaction under a home cage and novel environment were measured via resident–intruder and social interaction test, respectively. Furthermore, sexual preference, homosexual and heterosexual behaviors were measured.Results: Our study found that postweaning isolation increased the social affiliation for conspecifics (p = 0.001), reduced social recognition (p = 0.042) and impaired social memory. As for social interaction, isolated mice showed a remarkably increased aggression toward the intruder male in a home cage or novelty environment. For instance, isolated mice presented a short attack latency (p < 0.001), high attack frequency (p < 0.001) and long attack duration (p < 0.001). In addition, isolated mice exhibited further social avoidance. Contrastingly, isolated mice displayed a reduced sexual preference for female (IS: 61.47 ± 13.80%, GH: 70.33 ± 10.06%, p = 0.038). As for heterosexual behavior, isolated mice have a short mating duration (p = 0.002), long mounting latency (p = 0.002), and long intromission latency (p = 0.015). However, no association was observed between postweaning isolation and homosexual behavior in male CD-1 mouse.Conclusion: Postweaning isolation increased the social affiliation, impaired the social cognition and considerably increased the aggression in social interaction of adult male CD-1 mice. Postweaning isolation induced a decreased sexual preference for female in adulthood. Postweaning isolation extended the latency to mate, thereby reducing mating behavior. No association was observed between isolation and homosexual behavior

Nitrogen isotope composition of ammonium in PM 2.5 in the Xiamen, China: impact of non-agricultural ammonia

Abstract(#br)Since NH 3 is a significant precursor to ammonium in PM 2.5 and contributes significantly to atmospheric nitrogen deposition but largely remains unregulated in China, the insight into the source of NH 3 emissions by the isotopic investigation is important in controlling NH 3 emissions. In this study, atmospheric concentrations of NH 3 and water-soluble ion composition in PM 2.5 as well as nitrogen isotope ratios in NH 4 + (δ 15 N-NH 4 + ) in Xiamen, China, were measured. Results showed that average NH 3 concentration for the five sites in Xiamen was 7.9 μg m −3 with distinct higher values in the warm season and lower values in the cold season, and PM 2.5 concentration for the two sites (urban and suburban) was 59.2 μg m −3 with lowest values in summer. In the PM 2.5 , NH 4 +..

Nitrogen isotope composition of ammonium in PM2.5 in the Xiamen, China: impact of non-agricultural ammonia.

Since NH3 is a significant precursor to ammonium in PM2.5 and contributes significantly to atmospheric nitrogen deposition but largely remains unregulated in China, the insight into the source of NH3 emissions by the isotopic investigation is important in controlling NH3 emissions. In this study, atmospheric concentrations of NH3 and water-soluble ion composition in PM2.5 as well as nitrogen isotope ratios in NH4+ (δ15N-NH4+) in Xiamen, China, were measured. Results showed that average NH3 concentration for the five sites in Xiamen was 7.9 μg m-3 with distinct higher values in the warm season and lower values in the cold season, and PM2.5 concentration for the two sites (urban and suburban) was 59.2 μg m-3 with lowest values in summer. In the PM2.5, NH4+ concentrations were much lower than NH3 and showed a stronger positive correlation with NO3- than that with SO42- suggesting the formation of NH4NO3 and equilibrium between NH3 and NH4+. Although the concentrations of NH3 at the urban site were significantly higher than those at the suburban site, no significant spatial difference in NH4+ and δ15N-NH4+ was obtained. The distinct heavier δ15N-NH4+ values in summer than in other seasons correlated well with the equilibrium isotopic effects between NH3 and NH4+ which depend on temperature. The initial δ15N-NH3 values were in the range of waste treatment (- 25.42‰) and fossil fuel combustion (- 2.5‰) after accounting for the isotope fractionation. The stable isotope mixing model showed that fossil fuel-related NH3 emissions (fossil fuel combustion and NH3 slip) contributed more than 70% to aerosol NH4+. This finding suggested that the reduction of NH3 emissions from urban transportation and coal combustion should be a priority in the abatement of PM2.5 pollution in Xiamen

Plasmoid ejection and secondary current sheet generation from magnetic reconnection in laser-plasma interaction

Reconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson {\it et al.} [Phys. Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a solid target layer. An elongated current sheet (CS) was observed in the plasma between the two laser spots. In order to more closely model magnetotail reconnection, here two side-by-side thin target layers, instead of a single one, are used. It is found that at one end of the elongated CS a fan-like electron outflow region including three well-collimated electron jets appears. The ($>1$ MeV) tail of the jet energy distribution exhibits a power-law scaling. The enhanced electron acceleration is attributed to the intense inductive electric field in the narrow electron dominated reconnection region, as well as additional acceleration as they are trapped inside the rapidly moving plasmoid formed in and ejected from the CS. The ejection also induces a secondary CS

Exohedrally stabilized C-70 isomer with adjacent pentagons characterized by crystallography

NSFC [21031004, U1205111, 21021061]All C-70 isomers other than the well-known D-5h-symmetric C-70 (#8149) are highly elusive due to their defiance of the isolated pentagon rule (IPR), and, in turn, have long been underrated for years. Here we show a non-IPR hollow C-70 (#8064) with C-2-symmetry stabilized by exohedral chlorination as (C70Cl10)-C-#8064. Its connectivity with two pairs of fused pentagons was determined unambiguously by single crystal X-ray diffraction analysis. Based on the geometric criterion in terms of the pyramidalization angle as well as theoretical computations on the Kekule structure and the negative nucleus independent chemical shift, the exohedral stabilization of the labile C-#8064(70) is rationalized by releasing the local strain relevant to the fused pentagons and achieving the aromaticity of the remaining sp(2)-hybridized carbon framework in the exohedral derivative of C-#8064(70). This new entrant in the C-70 family, in addition to two previously reported non-IPR isomers (by Yang, Dunsch et al. for Sc3N@C-#7854(70) and by Echegoyen et al. for Sc2S@C-#7892(70)), provides valuable opportunities for experimental and theoretical research involving non-IPR isomers of C-70 beyond the common D-5h-C-70