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991.
Gloria Gutirrez‐Venegas Manuel Alejandro Snchez‐Carballido Claire Delmas Surez Juan Arturo Gmez‐Mora Nomie Bonneau 《Cell biology international》2020,44(3):686-720
Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV‐positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti‐inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models. 相似文献
992.
浙江是中国野生葡萄属资源分布较广泛、种类较多的地区之一,但对野生葡萄属资源的深入研究和合理开发利用不多。我们在野外调查和民间走访的基础上,结合查询文献资料,分析浙江境内野生葡萄资源的特点,并提出野生葡萄资源创新利用的思路。 相似文献
993.
Pegah Rahimizadeh Tohid Rezaei Topraggaleh Mohammad Hossein Nasr‐Esfahani Niloofar Ziarati Shahab Mirshahvaladi Vahid Esmaeili Soroush Seifi Poopak Eftekhari‐Yazdi Abdolhossein Shahverdi 《Molecular reproduction and development》2020,87(1):115-123
Failed oocyte activation has been observed in unexplained infertile (UI) and asthenoteratozoospermic (AT) men. The deficiency of phospholipase C‐zeta (PLCζ) could be a possible reason for such failures and has not been studied yet. We investigated the expression and localization of PLCζ protein in the sperms of patients with UI and AT conditions. The relationships between PLCζ‐related parameters with male age, sperm characteristics, DNA integrity, and cellular maturity were assessed. Semen samples were collected from fertile (n = 40), UI (n = 40), and AT (n = 40) men. Subsequently, semen analysis, DNA fragmentation, hyaluronic acid‐binding ability, and PLCζ level along with its distribution were evaluated using computer‐assisted sperm analyzer, sperm chromatin structure assay (SCSA), hyaluronic acid‐binding assay (HBA), western blot analysis and immunofluorescence microscopy, respectively. Unlike SCSA, the values of HBA, and PLCζ expression were significantly reduced in UI and AT patients compared to fertile men, whereas no significant differences were observed among the experimental groups in terms of PLCζ localization patterns. The regression analysis also showed that HBA is the only variable associated with PLCζ levels. Furthermore, the correlation of male age with PLCζ localization in postacrosomal, equatorial, and acrosomal+postacrosomal+equatorial (A+PA+E) patterns, as well as the relation of normal morphology, with the (A+PA+E) pattern, remained in the regression model. Our findings indicated that reduced PLCζ level along with the increased DNA fragmentation and impaired maturation may be possible etiologies of decreased fertilization in the studied subjects. 相似文献
994.
Does operational sex ratio influence relative strength of purging selection in males versus females?
Agata Plesnar‐Bielak Karolina Sychta Tomasz S. Gaczorek Joanna K. Palka Monika A. Prus Zofia M. Prokop 《Journal of evolutionary biology》2020,33(1):80-88
According to theory, sexual selection in males may efficiently purge mutation load of sexual populations, reducing or fully compensating ‘the cost of males’. For this to occur, mutations not only need to be deleterious to both sexes, they also must affect males more than females. A frequently overlooked problem is that relative strength of selection on males versus females may vary between environments, with social conditions being particularly likely to affect selection in males and females differently. Here, we induced mutations in red flour beetles (Tribolium castaneum) and tested their effect in both sexes under three different operational sex ratios (1:2, 1:1 and 2:1). Induced mutations decreased fitness of both males and females, but their effect was not stronger in males. Surprisingly, operational sex ratio did not affect selection against deleterious mutations nor its relative strength in the sexes. Thus, our results show no support for the role of sexual selection in the evolutionary maintenance of sex. 相似文献
995.
Chen S. L. Zhang L. P. Cai X. M. Bian L. Luo Z. X. Li Z. Q. Ge L. G. Chen Z. M. Xin Z. J. 《Russian Journal of Plant Physiology》2020,67(3):572-580
Russian Journal of Plant Physiology - The tea geometrid Ectropis grisescens is an important pest of tea plant (Camellia sinensis (L.) O. Kuntze). It feeds on the new leaves and tender... 相似文献
996.
Claudia Fricke Sergio vila‐Calero Sophie A. O. Armitage 《Journal of evolutionary biology》2020,33(7):930-941
Mating causes considerable alterations in female physiology and behaviour, and immune gene expression, partly due to proteins transferred from males to females during copulation. The magnitude of these phenotypic changes could be driven by the genotypes of males and females, as well as their interaction. To test this, we carried out a series of genotype‐by‐genotype (G × G) experiments using Drosophila melanogaster populations from two distant geographical locations. We expected lines to have diverged in male reproductive traits and females to differ in their responses to these traits. We examined female physiological and behavioural post‐mating responses to male mating traits, that is behaviour and ejaculate composition, in the short to mid‐term (48 hr) following mating. We then explored whether a sexually transferred molecule, sex peptide (SP), is the mechanism behind our observed female post‐mating responses. Our results show that the genotypes of both sexes as well as the interaction between male and female genotypes affect mating and post‐mating reproductive traits. Immune gene expression of three candidate genes increased in response to mating and was genotype‐dependent but did not show a G × G signature. Males showed genotype‐dependent SP expression in the 7 days following eclosion, but female genotypes showed no differential sensitivity to the receipt of SP. The two genotypes demonstrated clear divergence in physiological traits in short‐ to mid‐term responses to mating, but the longer‐term consequences of these initial dynamics remain to be uncovered. 相似文献
997.
Anna H. York‐Andersen Qinan Hu Benjamin W. Wood Mariana F. Wolfner Timothy T. Weil 《Molecular reproduction and development》2020,87(2):293-304
Egg activation is the essential process in which mature oocytes gain the competency to proceed into embryonic development. Many events of egg activation are conserved, including an initial rise of intracellular calcium. In some species, such as echinoderms and mammals, changes in the actin cytoskeleton occur around the time of fertilization and egg activation. However, the interplay between calcium and actin during egg activation remains unclear. Here, we use imaging, genetics, pharmacological treatment, and physical manipulation to elucidate the relationship between calcium and actin in living Drosophila eggs. We show that, before egg activation, actin is smoothly distributed between ridges in the cortex of the dehydrated mature oocytes. At the onset of egg activation, we observe actin spreading out as the egg swells though the intake of fluid. We show that a relaxed actin cytoskeleton is required for the intracellular rise of calcium to initiate and propagate. Once the swelling is complete and the calcium wave is traversing the egg, it leads to a reorganization of actin in a wavelike manner. After the calcium wave, the actin cytoskeleton has an even distribution of foci at the cortex. Together, our data show that calcium resets the actin cytoskeleton at egg activation, a model that we propose to be likely conserved in other species. 相似文献
998.
Nayara F. C. Castro Luiz R. Falleiros‐Júnior Mariele I. Zuco Ana P. S. Perez Sebastio R. Taboga Fernanda C. A. Santos Patrícia S. L. Vilamaior 《Cell biology international》2020,44(7):1467-1480
Prenatal and neonatal exposure to estrogenic compounds, such as ethinylestradiol (EE), promotes a variety of developmental disorders, including malformations and alterations in the morphology of glands, such as the prostate gland. Therefore, the aim of this study was to evaluate the morphological effects of neonatal exposure to EE on prostatic tissue and on the identification and quantification of gerbil gland macrophages in adult and senile Mongolian gerbils. The animals were exposed to EE (10 μg/kg/day) and to the vehicle, mineral oil (100 μL) (control group) during the first 10 days of postnatal life (lactation period). Adult gerbils were euthanized at 120 days and senile gerbils at 12 months of age. Our findings permitted verification of the presence of areas with proliferative foci in the prostate glandular portions in the adult and senile animals exposed to EE. There was also an increase in macrophages in the prostate tissue of adult and senile gerbils; these cell types alter the stromal microenvironment and possibly modify the interactions between the epithelium and stroma. Neonatal exposure to EE changes the pattern of prostatic development, leading to alterations in the arrangement of cells, including macrophages, and may be related to the onset of proliferative disorders in the prostate of adult gerbils and during aging. 相似文献
999.
1000.
Mi Hye Kim Jae Yeop Kim Jung‐Hak Kim Hyun‐Shik Lee Jae‐Won Huh Dong‐Seok Lee 《Cell biology international》2020,44(10):2086-2093
Reactive oxygen species (ROS) act as signaling molecules to regulate various cell functions. Numerous studies have demonstrated ROS to be essential for the differentiation of adipocytes. Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant enzymes in mammalian cells. Prx2 is present in the cytoplasm and cell membranes and demonstrates ROS scavenging activity. We focused on Prx2 involvement in regulating adipogenesis and lipid accumulation and demonstrated that Prx2 expression was upregulated during adipocyte differentiation. In addition, the silencing of Prx2 (shPrx2) inhibited adipogenesis by modulating adipogenic gene expression, and cell death was enhanced via increased ROS production in shPrx2‐3T3‐L1 cells. These results demonstrate that shPrx2 triggers adipocyte cell death and weakens adipocyte function via ROS production. Taken together, our data suggest the participation of Prx2 in adipocyte function and differentiation. Our results also imply that the downregulation of Prx2 activity could help prevent obesity. Overall, findings support the development of ROS‐based therapeutic solutions for the treatment of obesity and obesity‐related metabolic disorders. 相似文献