944 resultados para SALIVARY-GLANDS


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Fridericia nanningensis, a new species from wetland soil of Nanhu Park, Nanning city, the capital of Guangxi Zhuang Autonomous Region in southwest China, is described. It is characterized by 2-4 chaetae per bundle, poorly-developed clitellar glands, slender, unbranched peptonephridia, and spermathecae with 2 ampullar diverticula, a deep constriction in the middle of the ampulla and one large ectal gland. It is closely related to the European species, F. alata Nielsen & Christensen, 1959 and the East European species, F. tubulosa Dozsa-Farkas, 1972 by the shape of peptonephridia and the undeveloped clitellar glands. It differs from F. alata by its shorter body length and fewer chaetae per bundle, its type of coelomocytes (type "c"), its deep constriction in the middle of the spermathecae ampulla and a larger ectal gland, and it differs from F. tubulosa by its pale epidermal glands, its more anterior origin of the dorsal vessel, a deep constriction in the middle of the spermathecae ampulla, shorter ectal duct, and only one ectal gland at the spermathecal orifice.

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角蟾科(Megophryidae)是以角蟾属(Megophrys Kuhl and Van Hasselt, 1822)为模式属而建立的,隶于无尾目(Anura),变凹型亚目(Anomocoela)。角蟾科包括2 亚科11 属142 种,分布于东洋界,从巴基斯坦、中国西部向东直到菲律宾和苏达群岛;中国有9 属75 种分布于华中和华南地区。角蟾科被认为是原始的两栖动物之一,其分类学、系统学、生态学、动物地理学的研究均深受中外科学家的瞩目。近年来,通过形态学、古生物学、细胞学、生态学、支序系统学的研究,角蟾科的分类与系统学研究取得了较大进展。与成体形态和分子系统学研究结果相比较,蝌蚪的研究存在更多的问题和挑战,尚需深入研究:(1)角蟾科蝌蚪的形态多样性分析;(2)角蟾科的系统发育关系与蝌蚪的演化,以及口漏斗的起源;(3)角蟾科蝌蚪表型分化与栖息环境和觅食行为的适应演化。针对上述问题,本文对角蟾科9 属30 种蝌蚪的形态特征,包括外部宏观形态和口器外部结构特征、口器内部显微结构、唇齿和角质颌的亚显微结构作了深入细致、多层次的比较研究;通过12s rRNA 和cytochrome b 基因构建最大简约树,采用贝叶斯系统发育进行分析,蝌蚪型的演化采用祖先性状的重建方法分析;得到如下结论:1)初步将角蟾科蝌蚪分为4 种类型;并且建立了2 种新的角蟾科蝌蚪类型。A 型:拟髭蟾型蝌蚪,该型蝌蚪包括拟髭蟾属、髭蟾属、齿蟾属和齿突蟾属的物种;B 型:新类型,掌突蟾型蝌蚪,该型蝌蚪在本文中包括掌突蟾属、小臂蟾属的物种;C 型:新类型,短腿蟾型蝌蚪,一种特化类型,该型蝌蚪在本文中仅包括短腿蟾属的物种;D 型:角蟾型蝌蚪,该型蝌蚪在本文中包括无耳蟾属、小口拟角蟾属和异角蟾属的物种。2)对角蟾科的分类进行了修订:(1)支持角蟾科两个亚科的分类系统;(2)角蟾亚科包括拟角蟾属、异角蟾属、无耳蟾属和短腿蟾属;该亚科形态差异小,系统学关系比较复杂,暂不作族级分类的再划分;(3)拟髭蟾亚科分为2 个族:拟髭蟾族,该族物种具有类型A 的蝌蚪,包括4 个属:拟髭蟾属、髭蟾属、齿蟾属、齿突蟾属;掌突蟾族,该族物种具有类型B 的蝌蚪,包括2 个属:掌突蟾属和小臂蟾属。3)结合分子系统进化关系探讨了4 种蝌蚪类型的演化。(1)角蟾科蝌蚪的最近共同祖先来自于一类具有拟髭蟾型蝌蚪性状的蝌蚪;(2)掌突蟾型蝌蚪和角蟾亚科的蝌蚪是由具有拟髭蟾型蝌蚪性状的祖先蝌蚪分别演化而来;(3)短腿蟾型蝌蚪是角蟾型蝌蚪的一种特化类型;(4)外群蝌蚪具有与拟髭蟾型蝌蚪相似的性状,进一步印证了类拟髭蟾型蝌蚪是角蟾科蝌蚪的最近共同祖先的假说;(5)具有口漏斗的蝌蚪类型是由不具口漏斗的蝌蚪类型演化而来,在角蟾科中口漏斗是一种衍生性状。4)分析了角蟾科四种蝌蚪类型与栖息环境的适应演化。(1)角蟾科蝌蚪的口部和体形的变化反映了该科蝌蚪由缓流向类似静水生境的回水凼的渐变式适应,角蟾科蝌蚪的形态显示了多方面的适应变化;(2)随着蝌蚪类型由A 向D的演化,当水速较大时,拟髭蟾型的蝌蚪营流水攀吸型生活方式;当水速递减时,掌突蟾型蝌蚪营流水附着型生活方式;当水速进一步递减时,具有较小口漏斗的短腿蟾型蝌蚪和具有大漏斗的角蟾型蝌蚪营流水浮泳型生活。角蟾科蝌蚪对于水流递减的适应演化说明蝌蚪的生态学适应是具有进化意义的;(3)蝌蚪口器内部结构的分化揭示了蝌蚪和食性的适应关系,蝌蚪以口部的唇齿与角质颌刮取或吞吸水中的物质,然后,通过口乳突有选择地过滤进入口腔中食物。拟髭蟾亚科蝌蚪的唇齿多而窄,唇齿间距宽,颌鞘粗而稀,反映了其植食性为主的特点;它们的舌前乳突一般为指状,在口腔入口处所占面积小,其机械过滤的作用很多被唇齿和角质颌分担了;而角蟾亚科的蝌蚪,其角质颌弱,其舌前乳突一般为匙状,几乎填满了口腔入口处,因此舌前乳突起了主要的机械过滤作用。The family Megophryidae is the largest and most diverse families inArchaeobatrachia, and most of its species occur in India, Pakistan, and eastward intoChina, Southeast Asia, Borneo and the Philippines to the Sunda Islands. Currently thefamily includes 142 species have been grouped into two subfamilies, Megophryinaeand Leptobrachiinae. The mountains of central and southern China are rich in speciesof Megophryidae, 75 species belong to 9 genera and two subfamilies.The family was supposed to be ideal materials of studies in many fields of biology,such as taxonomy, evolution, systematics, ecology, and biogeography. Recently, therehave a great development in taxonomy and systematics of megophryids throughstudied by morphology, paleontology, cytology, ecology, and cladistics. However,larvae of megophryids were generally unknown, although the tadpoles might be veryimportant for above studies.In this paper, we examined the evolutionary scenario of the tadpoles’ morphologyin the context of a phylogenetic framework. Our objectives are (1) to evaluate thedivergence of larval body shape and oral discs in the family Megophryidae, (2) toexplore the evolutionary trends of the larvae in megophryidae, and test if thefunnel-shaped oral disc is apomorphic, and (3) to explore the relationship of the larvalstructure, diet and microhabitat.We examined larval morphology of 30 megophryid species, the larval body shape,oral discs, the buccopharyngeal cavity, and jaw sheaths and denticles of the Chinesemegophryid frogs were re-examined. We constructed a phylogeny of the species on thebasis of published mitochondrial cytochrome b and 16S rRNA gene segments usingpartitioned Bayesian analyses. Furthermore, hypothetical changes of larval morphologywere inferred using parsimony principle on the phylogeny. The results showed that:1) Four tadpole types in Megophryidae. The larval morphological charactersseries in Chinese megophryids fall into four general categories according to the bodyshape and oral discs: (A) Leptobrachiini type, species from genera Leptobrachium,Oreolalax, Scutiger and, Vibrissaphora share this type of tadpoles. (B) Leptolalax type,species of genus Leptolalax have this type of tadpoles. (C) Brachytarsophrys type,species of the genus Brachytarsophrys have this type of tadpoles. (D) Megophryinitype, species of the genera Atympanophrys, Ophryophryne, and Xenophrys share this type of tadpoles. Of which B and C are two novel types.2)Taxonomic implications. The present study leads us to reconsider the generalclassification of tribes attributed to members of Megophryidae. More specifically,concerning the phylogenetic relationships and the two novel tadpole types describedherein, we propose a provisional taxonomy for the family but suggest that further taxasampling of other megophryids be performed to confirm this taxonomic change. TheMegophryidae is composed of two subfamilies (Leptobrachiinae and Megophryinae).The Leptobrachiinae was recogonized the two tribes: (1) tribe Leptobrachiini sensuDubois, corresponding to the tadpole of type A, including four genera, i.e.,Leptobrachium, Oreolalax, Scutiger and, Vibrissaphora; (2) tribe Leptolalaxini,corresponding to the tadpole of novel type B, including two genera, i.e., Leptolalaxand Leptobrachella. However, the relationships among the genera of Megophryinaewere largely unresolved, they recognized no monophyletic groups above the generalevel. A more thorough sampling will likely foster a better taxonomic solution.3) The larval evolutionary scenario in Megophryidae.Type A is characteristicof normal-mouthed with multiple tooth rows, representing the tadpole type of theMRCA of Chinese megophryids. Type B is characteristic of normal-mouthed withreduced tooth rows, prolonging labium, and integumetary glands. Type C ischaracteristic of no labial teeth and smaller umbeliform oral disc. Type D ischaracteristic of no labial teeth, enlarged umbeliform oral disc, representing the tadpoleof the MRCA of subfamily Megophryinae. A previous hypothesis, referring tofunnel-shaped oral discs as an apomorphy, is supported.4) The larval adaptation to habitats in Megophryidae. Tadpoles generallyadhere to substrates using their mouths, and the microhabitat that the tadpoles occupyreflects the degree of adhesion and oral complexity. The morphological changes inmegophryid tadpoles virtually allow a progressive adaptation to a changing habitatfrom faster water to slower water. Within the tadpoles of Type A to type D, the TOTbecomes smaller and smaller, and the oral disc orientates from anteroventral toumbelliform upturned, and eye position orientates from dorsal to lateral, and the trunkis more and more depressed and tail becomes relatively longer and slender. Within therunning water, the normal-mouthed with multiple tooth rows of Leptobrachiini tadpoles are correlated with lotic-suctorial, benthic feeders with anteroventral oraldisc and the largest body. With the water’s velocity decreasing, the lotic-adherentfeeders of Leptolalax tadpoles have tube-shaped labium with reduced tooth rows andintegumetary glands. And then, the smaller umbeliform in Brachytarsophrys tadpolesand the enlarged umbeliform oral disc in the Megophryini tadpoles are inhabitmicrohabitats of non-flowing backwaters of rivers, indicative of adaptive traits oflotic-neustonic surface feeders. The scheme of megophryid tadpoles andmicrohabitats provided the first clear evidence which congruent with the hypothesis ofAltig and Johnston (1989). The ecological divergence plays a general role in thedivergence and evolution of megophrid larvae. There is a definite correlation amongthe buccopharyngeal cavity, diet and feeding mechanisms, the tadpole graze orswallow the food particles, then through papillae which like a sieve and sort out foodparticles to the oesophagus. The tadpole of Leptobrachiinae possess multiple toothrows, wide intertooth distance as well as thick and sparse jaw sheath, these tadpolesinhabit bottom of the streams and graze on epiphyton or major detritus of organicmatter on the substrates, their prelingual papillae like single finger, the mechanicalpurpose of papillae served share in by tooth and jaw. The tadpoles of Megophryinaeoccur near the water surface of small streams and are the filter feeder, their dietincludes plankton and organic debris floating on the water surface, those tadpolepossess weak jaw, their prelingual papillae like spoon, the mechanical purpose ofpapillae served mostly for sieve.

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To explore the potential of double irradiation source, radioactive C-9-ion beam, in tumor therapy, a comparative study oil the surviving effect of human salivary gland cells at different penetration depths between C-9 and C-12-ion beams has been carried out. The 9C-ion C beam, especially at the distal side of the beam came out more efficient in cell killing at the depths around its Bragg peak than the 12 Bragg peak. Compared to the C-12 beam, an increase in RBE by a factor of up to 2.13 has been observed at the depths distal to the Bragg peak of the 9C beam. The 9C beam showed an enhanced biological effect at the penetration depths around its Bragg peak, corresponding to the stopping region of the incident C-9-ions and where the delayed low-energy particles were emitted. Further analysis revealed that cell lethality by the emitted particles from the stopping C-9-ions is responsible for the excessive biological effect at the penetration depths around the Bragg peak of the C-9 beam.

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The ontogenetic development of the digestive enzymes amylase, lipase, trypsin, and alkaline phosphatase and the effect of starvation in miiuy croaker Miichthys miiuy larvae were studied. The activities of these enzymes were detected prior to exogenous feeding, but their developmental patterns differed remarkably. Trypsin activity continuously increased from 2 days after hatching (dah), peaked on 20 dah, and decreased to 25 dah at weaning. Alkaline phosphatase activity oscillated at low levels within a small range after the first feeding on 3 dah. In contrast, amylase and lipase activities followed the general developmental pattern that has been characterized in fish larvae, with a succession of increases or decreases. Amylase, lipase, and trypsin activities generally started to increase or decrease at transitions from endogenous to exogenous feeding or diet changes, suggesting that these enzymatic activities can be modulated by feeding modes. The activities of all the enzymes remained stable from 25 dah onwards, coinciding with the formation of gastric glands and pyloric caecum. These results imply that specific activities of these enzymes underwent changes due to morphological and physiological modifications or diet shift during larval development but that they became stable after the development of the digestive organs and associated glands was fully completed and the organs/glands functioned. Trypsin and alkaline phosphatase were more sensitive to starvation than amylase and lipase because delayed feeding up to 2 days after mouth opening was able to adversely affect their activities. Enzyme activities did not significantly differ among feeding groups during endogenous feeding; however, all activities were remarkably reduced when delayed feeding was within 3 days after mouth opening. Initiation of larvae feeding should occur within 2 days after mouth opening so that good growth and survival can be obtained in the culture.

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Shell formation is one of the important events during larval development and metamorphosis in bivalves. However, the molecular mechanisms and environmental cues regulating shell initiation and growth are unclear. Here, we report that ferritin, a principal protein for biological iron storage and metabolism, might play a role in larval shell development of the bivalve mollusk Meretrix meretrix. A full-length ferritin subunit cDNA, named as MmeFer, was cloned and characterized. The MmeFer mRNA expression in different developmental stages, from trochophore to post larvae, was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR). MmeFer mRNA expression in larvae of later developmental stages increased at least 8-fold following trochophores. Moreover, the temporal and spatial expressions of MmeFer mRNA were examined by whole mount in situ hybridization. In the trochophore stage, MmeFer was detectable where it was supposed to be for shell initiation. In the later developmental stages, MmeFer was found near digestive glands and mantle that secret larval shell. MmeFer expression was also detected in larvae cultured in artificial seawater with different iron concentrations ranging from 0 to 100 mu M. These results suggest that ferritin may play a role in the shell formation of mollusks. (C) 2009 Elsevier Inc. All rights reserved.

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Growth hormone (GH), prolactin (PRL) and somatolactin (SL) were purified simultaneously under alkaline condition (pH 9.0) from pituitary glands of sea perch (Lateolabrax japonicas) by a two-step procedure involving gel filtration on Sephadex G-100 and reverse-phase high-performance liquid chromatography (rpHPLC). At each step of purification, fractions were monitored by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and by immunoblotting with chum salmon GH. PRL and SL antisera. The yields of sea perch GH, PRL and SL were 4.2, 1.0 and 0.28 mg/g wet tissue, respectively. The molecular weights of 19,200 and 20,370 Da were estimated by SDS-PAGE for sea perch GH and PRL, respectively. Two forms of sea perch SL were found: one (28,400 Da) is probably glycosylated, while the other one (23,200 Da) is believed to be deglycosylated. GH bioactivity was examined by an in vivo assay. Intraperitoneal injection of sea perch GH at a dose of 0.01 and 0.1 mug/g body weight at 7-day intervals resulted in a significant increase in body weight and length of juvenile rainbow trout. The complete sea-perch GH amino acid sequence of 187 residues was determined by sequencing fragments cleaved by chemicals and enzymes. Alignment of sea-perch GH with those of other fish GHs revealed that sea-perch GH is most similar to advanced marine fish, such as tuna, gilthead sea bream, yellowfin porgy, red sea bream, bonito and yellow tail with 98.4, 96.2%, 95.7%, 95.2%, 94.1% and 91% sequence identity, respectively. Sea-perch GH has low identity to Atlantic cod (76.5%), hardtail (73.3%), flounder (68.4%), chum salmon (66.3%), carp (54%) and blue shark (38%). Partial amino-acid sequences of 127 of sea-perch PRL and the N-terminal of 16 amino-acid sequence of sea-perch SL have been determined. The data show that sea-perch PRL has a slightly higher sequence identity with tilapia PRL( 73.2%) than with chum salmon PRL(70%) in this 127 amino-acid sequence. (C) 2001 Elsevier Science B.V. All rights reserved.

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海水经济鱼类的养殖在我国已经形成第四次海水养殖浪潮,经济效益显著,有力地推动了我国海水养殖的产业结构调整和可持续发展。然而在海水养殖发展过程中也存在着诸多问题,尤其是早期发育阶段的高死亡率,严重制约了我国海水养殖产业的稳定和健康发展。 海水鱼类养殖的关键为高质量,高存活率苗种的生产和培育,由于鱼类种类繁多,生物多样性丰富,对应实际的繁育技术,尤其是新品种的开发,必须要做出相应的调整。这就要求我们必须对每一种鱼类早期发育有所了解,并将形态和组织上的数据用于指导生产。 本文通过显微观察和组织学研究,主要描述和研究了我国北方三种重要的海水经济鱼类(条斑星鲽、杂交鲆、条石鲷)的早期发育生物学,并结合实际生产进一步阐明关键期的产生原因,机理以及采用相应的对策。具体结果如下: 1.条斑星鲽:作为冷温性鲆鲽鱼类,条斑星鲽早期发育过程的特征主要有: ① 条斑星鲽受精卵无油球,卵子呈半浮性;不同步卵裂现象提前,发生在第三次卵裂;卵裂期裂球大小差异大。孵化过程较长,在水温8 ± 0.3℃,盐度33的条件下,经9 d孵化。条斑星鲽胚胎发育的不同时期对温度的敏感性不同,其中原肠期对温度比较敏感。 ②在8-10℃,盐度33的条件下,8-9 dph开口摄食。且开口时,其吻前端出现有一点状黑褐色素,构成了条斑星鲽仔鱼“开口期”的重要标志。卵黄囊于消失。在后期仔鱼末期,背鳍和臀鳍上形成特有的黑褐色条斑带。 ③杯状细胞首先出现在咽腔后部和食道前段,胃腺和幽门盲囊出现于29 dph,变态期始于30dph。在条斑星鲽早期发育过程中,观察到其直肠粘膜层细胞质出现大量嗜伊红颗粒,为仔鱼肠道上皮吸收的蛋白质。 ④首先淋巴化的免疫器官是头肾,然后是胸腺和脾脏,这与大部分硬骨鱼类不同。条斑星鲽除头肾和脾脏外,胸腺实质也形成MMCs。其中以脾脏形成MMCs最为丰富,形态多样。 2. 杂交鲆:为同属的牙鲆和夏鲆间的远缘杂交种,其发育过程的特点为: ① 在温度为15.4~16.0℃,杂交鲆胚胎从受精到孵化所需的时间为76 h左右,胚孔关闭前期,胚胎先出现视囊及克氏囊,而后形成体节。孵出前胚体在卵膜内环绕不到1周。 ② 孵化后消失。杂交鲆群体变态间隔长(34-60 dph),且变态高峰期出现的冠状幼鳍不明显(与母本牙鲆相比),数量为7-8根。 ③组织学观察发现,其消化系统中胃腺出现较晚,且胃腺发育过程缓慢(与母本牙鲆相比)。甲状腺滤泡增生不明显,颜色较浅,数量较少。杂交鲆在早期发育过程中,并没有出现鳔原基。 3. 条石鲷作为岩礁性的暖水性鱼类,早期发育过程也较为特殊,包括外形以及内部的器官结构。主要特点有: ① 受精卵:受精卵卵黄上具有龟裂结构,为鱼卵的分类特征之一。 ② 初孵仔鱼:初孵仔鱼背鳍膜上的黑色素,从体背面向背鳍膜边缘移动,到3dph仔鱼基本消失,此为本种仔鱼发育所特有的特点。 ③ 后期仔鱼和稚鱼:肠道肌肉层加厚明显,仔稚鱼胃肠排空率急剧上升,死亡率增加,通过改善常规的投饵方式部分解决了这个死亡高峰的问题。在幼鱼初期,牙齿融合为骨喙,为石鲷科鱼类的特征。 ④胸腺上皮分泌细胞:类似的现象同样在虹鳟鱼中发现,但是虹鳟鱼胸腺上皮分泌细胞不如条石鲷的丰富,同样也不如条石鲷的排列整齐,而是零星分布在胸腺上皮与咽腔接触的表面。除了正常的造血器官—脾脏和头肾外,肝脏、胰腺和鳔等多种组织等也出现MMCs,此现象在硬骨鱼类不多见,一般发生在软骨鱼类。

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A nnual changes of the rep roduct ive act ivity in adult male p lateau p ika (Ochotona curzoniae) , a small endemic mammal in Q inghai2T ibet P lateau, w ere invest igated from J anuary to December, 1991. A ll of the animals w ere k illed and decap itated during the nigh t (23:00~ 24:00) and the p lasma, p ineal glands, testes ep ididym is, sem inal vesicles, deferent ducts were co llected and used for biochemical, and histo logical studies. Significant changes associated with seasonal cycles were found. (1) In February~ early April, the restoration phase, the weights of testes, epididym ides and deferent ducts were increased; the process of sperm atogenesis was strengthened and testo sterone level in plasma was increased, but the pineal weight and its melatonin content were decreased. (2) During the middle of April~ late May, the sexually active phase, a significant elevation of gonadal activity was observed. In this period, gonadalw eights were increased, spermatogenesis was completed, pineal weights were decreased and melatonin contents were fluctuated at alow level. These results suggested the increasing in sexual activity as well as in the ability of testo sterone secretion. (3) A striking reduction of test icular activity appears in June~A ugust. In this inhibition phase, gonada lweight, process of sperm atogenesis, plasma testo sterone level were decreased while the pineal weight and pineal melatonin content were increased. (4) During Sep tember~ J anuary, the sexually quiescent phase, declining in weights of testes and epididymides, arrest of spermatogenesis, decreasing of plasma testo sterone concent ration, fluctuating in pineal weights and increasing in pinealmelatonin level were observed. Our findings indicated that the male pikas under natural conditions exhibited an annual rep roductive cycle. A possible relationship between pineal activity and reproductive function was also suggested.

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To better understand the floral diversity and the phylogeny of the Swertiinae (Gentianaceae), the internal transcribed spacer (ITS) region of nrDNA for 17 species and one outgroup was sequenced. Our data suggest that corolla type, gland shape, and corolla appendage are poorly correlated with the ITS phylogeny. The genus Swertia s.l. and the rotate group previously recognized based on the corolla types and gland shapes are polyphyletic. Four genera with simple protruding glands and three taxa with corolla appendages are not clustered as the monophyletic groups. Four separate clades, corresponding to the four sections, were identified in Swertia s.1. Lomatogoniopsis with the simple protruding gland type of the tubular group closely related to Lomatogonium of the rotate group. The deeply lobing corolla and concave foveae may be ancestral in the Swertiinae, while the tubular corolla and the protruding glands may have undergone convergent evolution.

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Recently there emerged more and more researhes concerning about sex hormone-related cognitive ability and behaviours. Few were carried out in pre- to early adolescent children., and the objective of the current study is to investigate whether there are covariance between sex hormones, intelligence and personality in 232 pre- to early adolescent boys, including 62 gifted boys. Indexes of sex hormone levels were salivary testosterone and estradiol concentrations, the 2D:4D digit ratio ( a reliable pointer of prenatal sex hormone concentraions). The Cattell Culture Fair Intelligence Test and a Chinese version of Children’s Personality Questionaire was applied in the current study. The main findings are: 1) salivary sex hormone concentrations significantly positively correlated with intelligence performance in 10-year-old boys; 2) salivary testosterone negatively related to intelligence performance in 12-year-old boys; 3) gifted boys bears lower testosterone concentrations in both prenatal period and pre- to early adolescence; 4) for personality, higher salivary estradiol was related to extraversion and digit ratios correlated with several personality factors in 8-year-old boys. In conclusion, results in the current study suggested that for male early maturers, intelligence may be negatively influenced by early coming androgen surge. In contrast, male late matures may benefit from their lately and moderately increasing hormone. Besides, the results suggested that the relationship between 2D:4D digit ratio and personality may also be paid attention to.

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Polycystic Ovary Syndrome (PCOS) is a complex disorder encompassing reproductive and metabolic dysfunction. Ovarian hyperandrogenism is an endocrine hallmark of human PCOS. In animal models, PCOS-like abnormalities can be recreated by in utero over-exposure to androgenic steroid hormones. This thesis investigated pancreatic and adrenal development and function in a unique model of PCOS. Fetal sheep were directly exposed (day 62 and day 82 of gestation) to steroidal excesses - androgen excess (testosterone propionate - TP), estrogen excess (diethylstilbestrol - DES) or glucocorticoid excess (dexamethasone - DEX). At d90 gestation there was elevated expression of genes involved in β- cell development and function: PDX-1 (P<0.001), and INS (P<0.05), INSR (P<0.05) driven by androgenic excess only in the female fetal pancreas. β- cell numbers (P<0.001) and in vitro insulin secretion (P<0.05) were also elevated in androgen exposed female fetuses. There was a significant increase in insulin secreting β-cell numbers (P<0.001) and in vivo insulin secretion (glucose stimulated) (P<0.01) in adult female offspring, specifically associated with prenatal androgen excess. At d90 gestation, female fetal adrenal gene expression was perturbed by fetal estrogenic exposure. Male fetal adrenal gene expression was altered more dramatically by fetal glucocorticoid exposure. In female adult offspring from androgen exposed pregnancies there was increased adrenal steroidogenic gene expression and in vivo testosterone secretion (P<0.01). This highlights that the adrenal glands may contribute towards excess androgen secretion in PCOS, but such effects might be secondary to other metabolic alterations driven by prenatal androgen exposure, such as excess insulin secretion Thus there may be dialogue between the pancreas and adrenal gland, programmed during early life, with implications for adult health Given both hyperinsulinaemia and hyperandrogenism are common features in PCOS, we suggest that their origins may be at least partially due to altered fetal steroidal environments, specifically excess androgenic stimulation

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McGuigan, M. R., Ghiagiarelli, J., Tod, D. (2005). Maximal strength and cortisol responses to psyching-up during the squat exercise. Journal of Sports Sciences, 23 (7), 687-692. RAE2008

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária

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BACKGROUND: Like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. Although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. As sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation. Using a molecular approach that combined analyses of biochemical and microsatellite markers in 17 female and 19 male ring-tailed lemurs (Lemur catta), we describe odor-gene covariance to establish the feasibility of olfactory-mediated kin recognition. RESULTS: Despite derivation from different genital glands, labial and scrotal secretions shared about 170 of their respective 338 and 203 semiochemicals. In addition, these semiochemicals encoded information about genetic relatedness within and between the sexes. Although the sexes showed opposite seasonal patterns in signal complexity, the odor profiles of related individuals (whether same-sex or mixed-sex dyads) converged most strongly in the competitive breeding season. Thus, a strong, mutual olfactory signal of genetic relatedness appeared specifically when such information would be crucial for preventing inbreeding. That weaker signals of genetic relatedness might exist year round could provide a mechanism to explain nepotism between unfamiliar kin. CONCLUSION: We suggest that signal convergence between the sexes may reflect strong selective pressures on kin recognition, whereas signal convergence within the sexes may arise as its by-product or function independently to prevent competition between unfamiliar relatives. The link between an individual's genome and its olfactory signals could be mediated by biosynthetic pathways producing polymorphic semiochemicals or by carrier proteins modifying the individual bouquet of olfactory cues. In conclusion, we unveil a possible olfactory mechanism of kin recognition that has specific relevance to understanding inbreeding avoidance and nepotistic behavior observed in free-ranging primates, and broader relevance to understanding the mechanisms of vertebrate olfactory communication.