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81.
Steffen Schneider Thomas Hofmann Stefan Stinchcombe Maria Cecilia Rey Moreno Ivana Fegert Volker Strauss Sibylle Gröters Eric Fabian Jutta Thiaener Karma C. Fussell Bennard van Ravenzwaay 《Birth defects research. Part B, Developmental and reproductive toxicology》2013,98(3):230-246
Epoxiconazole, a triazole‐based fungicide, was tested in toxicokinetic, prenatal and pre‐postnatal toxicity studies in guinea pigs, following oral (gavage) administration at several dose levels (high dose: 90 mg/kg body weight per day). Maternal toxicity was evidenced by slightly increased abortion rates and by histopathological changes in adrenal glands, suggesting maternal stress. No compound‐related increase in the incidence of malformations or variations was observed in the prenatal study. In the pre‐postnatal study, epoxiconazole did not adversely affect gestation length, parturition, or postnatal growth and development. Administration of epoxiconazole did not alter circulating estradiol levels. Histopathological examination of the placentas did not reveal compound‐related effects. The results in guinea pigs are strikingly different to those observed in pregnant rats, in which maternal estrogen depletion, pathological alteration of placentas, increased gestation length, late fetal death, and dystocia were observed after administration of epoxiconazole. In the studies reported here, analysis of maternal plasma concentrations and metabolism after administration of radiolabeled epoxiconazole demonstrated that the different results in rats and guinea pigs were not due to different exposures of the animals. A comprehensive comparison of hormonal regulation of pregnancy and birth in murid rodents and primates indicates that the effects on pregnancy and parturition observed in rats are not applicable to humans. In contrast, the pregnant guinea pig shares many similarities to pregnant humans regarding hormonal regulation and is therefore considered to be a suitable species for extrapolation of related effects to humans. Birth Defects Res (Part B) 98:230–246, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
82.
Typification of the names Antirrhinum barrelieri Boreau, A. controversum Pau and A. litigiosum Pau (Antirrhineae, Plantaginaceae) is needed to clarify the use and concept of these three names. The origin of a misinterpretation of the name A. barrelieri, which conditioned the subsequent use of these three names, is discussed. The previous ‘lectotype’ of A. barrelieri designated by Rothmaler from a Barrelier's illustration is shown to be ineffective, being contrary to Art. 9.12 of the ICN, and therefore a lectotype is designated from a syntype preserved in the herbarium of the Muséum des sciences naturelles d'Angers (France) at ANG. The Pau's names A. controversum and A. litigiosum have not been typified before, and lectotypes are here designated from specimens preserved at P and MA, respectively. As a consequence, the name A. litigiosum should be treated as a later heterotypic synonym of A. barrelieri. 相似文献
83.
Li Chen Jing-Jing Zhang Xia Zhang Xiaoli Liu Shuhong Zhao Li-Jun Huo Jilong Zhou Yi-Liang Miao 《Journal of cellular physiology》2020,235(3):2836-2846
Malathion (MAL) is a common organophosphorus pesticide and affects both animal and human reproduction. However, the mechanisms regarding how MAL affects the mammalian oocyte quality and how to prevent it have not been fully investigated. In this study, we used porcine oocyte as a model and proved that MAL impaired porcine oocyte quality in a dose-dependent manner during maturation. MAL decreased the first polar body extrusion, disrupted spindle assembly and chromosome alignment, impaired cortical granules (CGs) distribution, and increased reactive oxygen species (ROS) level in oocytes. RNA-seq analysis showed that MAL exposure altered the expression of 2,917 genes in the porcine maturated oocytes and most genes were related to ROS, the lipid droplet process, and the energy supplement. Nevertheless, these defects could be remarkably ameliorated by adding melatonin (MLT) into the oocyte maturation medium. MLT increased oocyte maturation rate and decreased the abnormities of spindle assembly, CGs distribution and ROS accumulation in MAL-exposed porcine oocytes. More important, MLT upregulated the expression of genes related to lipid droplet metabolism (PPARγ and PLIN2), decreased lipid droplet size and lipid peroxidation in MAL-exposed porcine oocytes. Finally, we found that MLT increased the blastocysts formation and the cell numbers of blastocysts in MAL-exposed porcine oocytes after parthenogenetic activation, which was mediated by reduction of ROS levels and maintaining lipid droplet metabolism. Taken together, our results revealed that MLT had a protective action against MAL-induced deterioration of porcine oocyte quality. 相似文献
84.
Penélope Cruzado-Caballero José Ignacio Ruiz-Omeñaca Rodrigo Gaete Violeta Riera Oriol Oms José Ignacio Canudo 《Historical Biology》2013,25(5):619-630
In the latest Maastrichtian, the European hadrosauroid fauna was more diverse than those of North America and Asia. The European record of hadrosaurid dentaries is an example of this diversity, and most of the sites with mandibular remains are located in the Ibero-Armorican Realm. Within the Iberian Peninsula, most of the remains are located in the Tremp Basin (South Central Pyrenees). Two of the three valid hadrosaurid taxa defined in this basin are from the Blasi sites (Arén, Huesca province): Arenysaurus ardevoli (Blasi-3) and Blasisaurus canudoi (Blasi-1). A new locality in Blasi (Blasi 3.4) has provided a new dentary from an indeterminate euhadrosaurid. This dentary presents some characters intermediate between Arenysaurus and Blasisaurus, some characters similar to Pararhabdodon isonensis (from the nearby province of Lleida), and some characters of its own. Nevertheless, due to its fragmentary character, without dentition or its edentulous anterior part, it cannot be determined above the level of Euhadrosauria. It thus represents a fourth Iberian euhadrosaurian taxon in the Ibero-Armorican Realm, different from Arenysaurus, Blasisaurus and Pararhabdodon, increasing the diversity of hadrosauroids in this realm at the very end of the Cretaceous. 相似文献
85.
David Miguélez 《法国昆虫学会纪事》2013,49(3):317-326
Information on flight dispersal in water beetles in the Iberian Peninsula is scarce. This study provides new data on the dispersion flight phenology of 21 species captured using Moericke traps in an agricultural system in León province (NW Spain) during two annual cycles (1992 and 1993). The species captured form part of the assemblage of aquatic Coleoptera commonly found in stagnant environments in the centre of the Iberian Peninsula. Most of them are good flyers and colonisers. These flights are related to two environmental variables: mean atmospheric temperature and rainfall. The results show a clear relation between temperature and the flight period as most of the specimens dispersed during peaks of high mean daily temperatures, and a negative relation with rainfall. With regard to phenology, two types of dispersion strategy were identified: flights in the middle of summer to escape from drought and flights in spring and autumn for colonising new habitats. The first group includes Hydroglyphus geminus (Fabricius) and, in particular, Helophorus brevipalpis Bedel, whose great abundance in the dispersal stage is related to parthenogenetic reproduction and the rapid production of a large number of colonising females. The second strategy corresponds to univoltine species with overwintering adults such as Helophorus alternans Gené or species from the genus Hydroporus Clairville. 相似文献
86.
Füsun Sipahiler 《水生昆虫》2013,35(2):115-125
In the present study, two new species of the tribe Chaetopterygini (Trichoptera, Limnephilidae) from north-eastern Turkey are described and illustrated. Rizeiella camiliensis sp.n. is the second species of the northern Anatolian genus Rizeiella and Kelgena macahelensis sp.n. is the third species of the Caucasian genus Kelgena. 相似文献
87.
The stridulatory organ of the Crematogaster scutellaris (Olivier 1792) workers is being described, comparing their pars stridens present in six nests of this species, with one nest of Crematogaster auberti Emery 1869 and with the bibliographical data regarding other neighbouring species at our disposal. Both species and some Crematogaster scutellaris nests have shown significant differences. We propose several hypotheses which could explain these differences. 相似文献
88.
89.
The diet of Perla madritensis, endemic species of the northern half of the Iberian Peninsula, is described for the first time by means of a study carried out in north-western Spain. As other species of the genus Perla, this taxon behaves mainly as predator, with Chironomidae, followed by Baetidae, being the most abundant prey in its gut. Shifts in diet composition were detected in relation to size in this species, with smaller prey being replaced by larger ones such as Simuliidae and Leptophlebiidae when the nymphs become larger. 相似文献
90.
通过在细胞和胚胎水平对猪Von Hippel-Lindau(VHL)基因进行了基因敲低研究,以便为建立VHL疾病模型猪奠定基础.研究首先通过 3'RACE和5'RACE克隆得到猪VHL基因cDNA全长序列(2 725 bp),Real-time PCR结果表明VHL基因广泛表达于猪的各种组织器官,其中在肾上腺、肝脏、胰腺、心脏和睾丸等组织器官高量表达.进一步在猪iPS细胞中对5条干扰片段进行筛选,获得2条高效的干扰片段,干扰效率分别达到72%(P=0.0012)和64% (P< 0.01).以稳定干扰VHL基因的猪胎儿成纤维细胞为核供体,构建克隆胚胎,结果表明,克隆胚胎的发育能力与对照组相比没有明显差异,而且在克隆囊胚中VHL基因的干扰效率达到71% (P< 0.01).综上所述,文中获得了猪VHL基因全长序列并获得该基因稳定敲低的猪细胞和胚胎,从而为VHL疾病模型猪的构建奠定了良好的基础. 相似文献