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331.
PDGFRs expression in dogs affected by malignant oral melanomas: correlation with prognosis 下载免费PDF全文
S. Iussich L. Maniscalco A. Di Sciuva B. Iotti E. Morello M. Martano F. Gattino P. Buracco R. De Maria 《Veterinary and comparative oncology》2017,15(2):462-469
Canine malignant melanoma (CMM) is the most common canine oral tumour, and up to 70–75% of dogs in stage II–III die within 1 year after surgery. The purpose of this study was to evaluate the expression of platelet‐derived growth factors receptors (PDGFR)‐α and ‐β in stage II and III CMMs and to correlate it with prognosis. PDGFRs expression was evaluated by immunohistochemistry on 48 cases of formalin‐fixed CMM samples and correlated with clinical–pathological findings and outcome after surgery. PDGFRs co‐expression was observed in 37.5% of cases. Positivity for PDGFR‐α and ‐β receptor was present in 54.2 and 47.9% of cases, respectively. Ki67 values >19.5% were ascertained in 66.7% of cases. Statistical analysis showed that PDGFRs co‐expression and Ki67 values > 19.5% were both associated with worse prognosis. PDGFRs expression suggests a role in the pathogenesis and progression of CMM, and α and β co‐expression appears to be associated to worse prognosis. 相似文献
332.
Seasonal or pathological findings? Morphofunctional characteristics of the equine endometrium during the autumn and spring transition 下载免费PDF全文
R Killisch D Böttcher T Theuß H Edzards G Martinsson A Einspanier J Gottschalk H‐A Schoon 《Reproduction in domestic animals》2017,52(6):1011-1018
The deep anoestrous phase in winter is part of the anovulatory season in mares and is bordered by the autumn and spring transitional periods (ATP/STP). To define an annual time span for effective prognostic biopsy sampling, the aim of this study was to provide a morphofunctional characterization of the endometrium during ATP and STP. To outline both transitional periods, endometrial specimens were taken in September, October and November (n = 76) as well as February, March and April (n = 184) with the requirement of a detailed clinical documentation. Tissue samples were examined histologically with special emphasis on the functional endometrial morphology. Additionally, an immunohistochemical evaluation was performed on selected specimens regarding the expression of oestrogen receptor α, progesterone receptor and Ki67‐antigen. An absent to low endometrial activity was ascertained in more than 60% of all specimens from late October onwards, whereas a comparably lacking or low activity in STP was observed until early April. Approximately 30% (ATP) to 22% (STP) of all samples exhibited a predominantly “irregular” endometrial differentiation. During the transitional periods, the clinically evaluated ovarian status (transrectal palpation, transrectal ultrasonography and/or serum progesterone and oestrogen analyses) and the endometrial functional morphology were in accordance with approximately 70% of all cases. The expression of steroid hormone receptors and Ki67‐antigen was generally low. Given that endometrial maldifferentiations were frequently found during ATP and STP, its occurence might display a characteristic and physiological feature of the transitional periods. Regarding the functional endometrial morphology, a diagnostic biopsy sampling should therefore be performed between late April and before September. 相似文献
333.
胰岛素是一类生物体内在进化上非常保守的具有调控代谢、生长、发育、生殖和寿命等多种功能的肽类激素。在昆虫中,以多基因家族编码的类胰岛素为主,在结构上与脊椎动物胰岛素同源。近年来,有关昆虫类胰岛素及其信号通路等方面已有较多研究,特别是对黑腹果蝇的研究,为人类胰岛素相关疾病诊断与治疗提供了较好的试验模型。本文主要介绍昆虫类胰岛素及其受体、类胰岛素表达与释放、类胰岛素信号通路及其在调控昆虫生殖、寿命、代谢、生长与发育和翅型分化等生理功能的最新研究进展,为促进其在害虫控制或天敌保护利用等方面的应用提供参考。 相似文献
334.
大弹涂鱼(Boleophthalmus pectinirostris)是一种生活在潮间带的淤泥滩和红树林等两栖环境中的鱼类,其免疫系统面临比水生生活更大的选择压力。Toll样受体基因(简称TLR)是重要的先天免疫成员,一直是鱼类分子免疫学的研究热点之一。为了探究大弹涂鱼TLR基因是否因为其独特的生活环境而产生适应性进化以及其TLR基因在受到细菌攻击后的免疫应答模式,本研究从大弹涂鱼皮肤转录组中获得了TLR5, TLR8和TLR9完整序列以及TLR3和TLR7部分序列,采用分子生物信息学对大弹涂鱼TLR5, TLR8和TLR9基因序列以及氨基酸序列进行了分析,并根据所构建的系统发育树对5个TLR基因进行了分子进化分析,采用荧光定量PCR方法对大弹涂鱼5个TLR基因的组织表达分布和鳗弧菌攻击后5个TLR基因的免疫应答模式开展了研究。结果显示, TLR5基因全长3071 bp,包括长度为2646 bp的编码区,共编码882个氨基酸;TLR8基因全长3175 bp,包括长度为3033 bp的编码区,共编码1011个氨基酸;TLR9基因全长3398 bp,编码区长度为3093 bp,共编码1031个氨基酸。大弹涂鱼3个TLR基因与其他物种的TLR基因结构相似,具有高度保守性。位点模型结果表明,鱼类TLR3, TLR5和TLR8是高度保守的,而TLR7和TLR9在长期进化过程中产生了适应性进化;而进化枝-位点模型结果表明,为了适应更加复杂多变的两栖环境,大弹涂鱼TLR9基因可能产生了适应性进化。大弹涂鱼5个TLR基因在8个健康组织(肠,眼,肾,肝,脑,肌肉,脾和皮肤)中均有表达,在肝脏和脾脏中的表达量较高。在受到鳗弧菌(Vibrio anguillarum)攻击后的免疫表达模式表明了大弹涂鱼5个TLR基因在应对细菌入侵时起到了重要作用。 相似文献
335.
Expression profiles and functional prediction of ionotropic receptors in Asian corn borer,Ostrinia furnacalis (Lepidoptera: Crambidae) 下载免费PDF全文
Genes involved in chemosensation are essential for odorant-mediated insect behaviors. Odorant receptors (ORs) bind and respond to pheromones and plant volatiles, regulating insect behaviors such as mating and host-plant selection, while ionotropic receptors (IRs), which are present at lower levels in insects than ORs, influence ion channels, especially in agricultural pests. Asian corn borer, Ostrinia furnacalis, is the main pest of maize that causes huge economic losses in Asia. Twenty-one OfurIRs have been identified, but none has been characterized. In this study, tissue-specific expression profiling, phylogenetic analysis, and electroantennography (EAG) analysis were applied to characterize the evolution, expression, and the potential function of OfurIRs. It was found that 20 OfurIRs were highly expressed in the antennae, except for OfurIR75p3, whereas 10 and nine OfurIRs were highly expressed in the proboscis and genitalia, respectively, indicating that these OfurIRs were functionally associated with feeding and oviposition. EAG results showed that seven acids elicited responses in the antennae of O. furnacalis and that 2-oxopentanoic acid displayed a significant female-biased response. Combined with the phylogenetic analysis, 10 OfurIRs in clade 4 were roughly predicted to be candidate receptors for 2-oxopentanoic acid and other tested acids. These results provide basic information about OfurIRs and may help advance the knolwedge on the olfactory system of O. furnacalis. 相似文献