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关键词： mammal   placental   sensory evolution   neuroanatomy   CT scanning   end-Cretaceous extinction  

摘要： Mammals underwent a profound diversification after the end-Cretaceous mass extinction, with placentals rapidly expanding in body size and diversity to fill new niches vacated by dinosaurs. Little is known, however, about the brains and senses of these earliest placentals, and how neurosensory features may have promoted their survival and diversification. We here use computed tomography (CT) to describe the brain, inner ear, sinuses, and endocranial nerves and vessels of Carsioptychus coarctatus, a periptychid "condylarth" that was among the first placentals to blossom during the few million years after the extinction, in the Paleocene. Carsioptychus has a generally primitive brain and inner ear that is similar to the inferred ancestral eutherian/placental condition. Notable "primitive" features include the large, anteriorly expanded, and conjoined olfactory bulbs, proportionally small neocortex, lissencephalic cerebrum, and large hindbrain compared to the cerebrum. An encephalization quotient (EQ) cannot be confidently calculated because of specimen crushing but was likely very small, and comparisons with other extinct placentals reveal that many Paleocene "archaic" mammals had EQ values below the hallmark threshold of modern placentals but within the zone of nonmammalian cynodonts, indicative of small brains and low intelligence. Carsioptychus did, however, have a "conventional" hearing range for a placental, but was not particularly agile, with semicircular canal dimensions similar to modern pigs. This information fleshes out the biology of a keystone Paleocene "archaic" placental, but more comparative work is needed to test hypotheses of how neurosensory evolution was related to the placental radiation. Anat Rec, 302:306-324, 2019. (c) 2018 Wiley Periodicals, Inc.

关键词： ommochrome   ommochromasome   pigment   photochemistry   antiradical capacity   phenoxazone   phenothiazine   melanosome   melanin   lysosome-related organelle  

摘要： Ommochromes are widely occurring coloured molecules of invertebrates, arising from tryptophan catabolism through the so-called Tryptophan -> Ommochrome pathway. They are mainly known to mediate compound eye vision, as well as reversible and irreversible colour patterning. Ommochromes might also be involved in cell homeostasis by detoxifying free tryptophan and buffering oxidative stress. These biological functions are directly linked to their unique chromophore, the phenoxazine/phenothiazine system. The most recent reviews on ommochrome biochemistry were published more than 30 years ago, since when new results on the enzymes of the ommochrome pathway, on ommochrome photochemistry as well as on their antiradical capacities have been obtained. Ommochromasomes are the organelles where ommochromes are synthesised and stored. Hence, they play an important role in mediating ommochrome functions. Ommochromasomes are part of the lysosome-related organelles (LROs) family, which includes other pigmented organelles such as vertebrate melanosomes. Ommochromasomes are unique because they are the only LRO for which a recycling process during reversible colour change has been described. Herein, we provide an update on ommochrome biochemistry, photoreactivity and antiradical capacities to explain their diversity and behaviour both in vivo and in vitro. We also highlight new biochemical techniques, such as quantum chemistry, metabolomics and crystallography, which could lead to major advances in their chemical and functional characterisation. We then focus on ommochromasome structure and formation by drawing parallels with the well-characterised melanosomes of vertebrates. The biochemical, genetic, cellular and microscopic tools that have been applied to melanosomes should provide important information on the ommochromasome life cycle. We propose LRO-based models for ommochromasome biogenesis and recycling that could be tested in the future. Using the context of insect compound eyes

关键词： microbiome   conservation   wildlife  

摘要： The central aim of conservation biology is to understand and mitigate the effects of human activities on biodiversity. To successfully achieve this objective, researchers must take an interdisciplinary approach that fully considers the effects, both direct and indirect, of anthropogenic disturbances on wildlife physiology and health. A recent surge in research has revealed that host-associated microbiota-the archaeal, bacterial, fungal and viral communities residing on and inside organisms-profoundly influence animal health, and that these microbial communities can be drastically altered by anthropogenic activities. Therefore, conservation practitioners should consider the disruption of host-associated microbial diversity as a serious threat to wildlife populations. Despite the tremendous potential for microbiome research to improve conservation outcomes, few efforts have been made to truly integrate these fields. In this review, we call for the microbial renaissance of conservation biology, where biodiversity of host-associated microbiota is recognized as an essential component of wildlife management practices. Using evidence from the existing literature, we will examine the known effects of anthropogenic activities on the diversity of host-associated microbial communities and integrate approaches for maintaining microbial diversity to successfully achieve conservation objectives.

关键词： Escherichia coli O157   ISO 16654:2001   Validation   Performance characteristics   CEN mandate No. M381  

摘要： In 2006, the European Committee for standardisation (CEN)/Technical Committee 275 - Food analysis Horizontal methods/Working Group 6 - Microbiology of the food chain (TC275/WG6), launched the project of validating the method ISO 16654:2001 for the detection of Escherichia coli O157 in foodstuff by the evaluation of its performance, in terms of sensitivity and specificity, through collaborative studies. Previously, a validation study had been conducted to assess the performance of the Method No 164 developed by the Nordic Committee for Food Analysis (NMKL), which aims at detecting E. coil O157 in food as well, and is based on a procedure equivalent to that of the ISO 16654:2001 standard. Therefore, CEN established that the validation data obtained for the NMKL Method 164 could be exploited for the ISO 16654:2001 validation project, integrated with new data obtained through two additional interlaboratory studies on milk and sprouts, run in the framework of the CEN mandate No. M381. The ISO 16654:2001 validation project was led by the European Union Reference Laboratory for Escherichia coli including VTEC (EURL-VTEC), which organized the collaborative validation study on milk in 2012 with 15 participating laboratories and that on sprouts in 2014, with 14 participating laboratories. In both studies, a total of 24 samples were tested by each laboratory. Test materials were spiked with different concentration of E. coil O157 and the 24 samples corresponded to eight replicates of three levels of contamination: zero, low and high spiking level. The results submitted by the participating laboratories were analyzed to evaluate the sensitivity and specificity of the ISO 16654:2001 method when applied to milk and sprouts. The performance characteristics calculated on the data of the collaborative validation studies run under the CEN mandate No. M381 returned sensitivity and specificity of 100% and 94.4%, respectively for the milk study. As for sprouts matrix, the sensitivity re

关键词： 动物系统学   实验   解剖   竞赛试题   奥林匹克   生物学   蝴蝶标本   特征矩阵  

摘要： 总分:100分,时间:90min,本考试包括以下2个实验部分:实验1:蝴蝶分类(65分),任务1鉴定所有提供的蝴蝶标本,任务2编制特征矩阵,任务3根据所提供的特征矩阵计算距离矩阵,任务4分析所有标本的系统发生关系,任务5绘制一个系统发生树,实验2:蚯蚓解剖(学名:Amynthas aspergillum)(35分),任务6识别蚯蚓的外部结构,任务7解剖并识别蚯蚓的内部结构。

关键词： CNV   Copy number variant   Genetic animal model   Genetics   Schizophrenia   Schizophrenia-related phenotype  

摘要： The diagnosis of schizophrenia rests on clinical criteria that cannot be assessed in animal models. Together with absence of a clear underlying pathology and understanding of what causes schizophrenia, this has hindered development of informative animal models. However, recent large-scale genomic studies have identified copy number variants (CNVs) that confer high risk of schizophrenia and have opened a new avenue for generation of relevant animal models. Eight recurrent CNVs have reproducibly been shown to increase the risk of schizophrenia by severalfold: 22q11.2(del), 15q13.3(del), 1q21(del), 1q21(dup), NRXN1(del), 3q29(del), 7q11.23(dup), and 16p11.2(dup). Five of these CNVs have been modeled in animals, mainly mice, but also rats, flies, and zebrafish, and have been shown to recapitulate behavioral and electrophysiological aspects of schizophrenia. Here, we provide an overview of the schizophrenia-related phenotypes found in animal models of schizophrenia high-risk CNVs. We also discuss strengths and limitations of the CNV models, and how they can advance our biological understanding of mechanisms that can lead to schizophrenia and can be used to develop new and better treatments for schizophrenia.

关键词： 原花青素   生物学特性   动物生产   应用  

摘要： 原花青素来源广泛、成本较低、绿色安全、生物活性高,具有促进动物生长、清除自由基抗氧化、提高机体免疫力、消炎、防腹泻、抗肿瘤等功能,是一种天然绿色饲料添加剂,近来在动物生产中应用广泛。本文对原花青素的营养价值、生物学功能以及在动物生产中的最新研究进展作一综述。

关键词： direct metal laser sintering   biomimetic   porous titanium   Ti6Al4V   3D-printing  

摘要： A mismatch of elastic modulus values could result in undesirable bone resorption around the dental implant. The objective of this study was to optimize direct metal laser sintering (DMLS)-manufactured Ti6Al4V dental implants' design, minimize elastic mismatch, allow for maximal bone ingrowth, and improve long-term fixation of the implant. In this study, DMLS dental implants with different morphological characteristics were fabricated. Three-point bending, torsional, and stability tests were performed to compare the mechanical properties of different designs. Improvement of the weaker design was attempted by augmentation with a longitudinal 3D-printed strut. The osseointegrative properties were evaluated. The results showed that the increase in porosity decreased the mechanical properties, while augmentation with a longitudinal weight-bearing strut can improve mechanical strength. Maximal alkaline phosphatase gene expression of MG63 cells attained on 60% porosity Ti6Al4V discs. In vivo experiments showed good incorporation of bone into the porous scaffolds of the DMLS dental implant, resulting in a higher pull-out strength. In summary, we introduced a new design concept by augmenting the implant with a longitudinal weight-bearing strut to achieve the ideal combination of high strength and low elastic modulus;our results showed that there is a chance to reach the balance of both biologic and mechanical demands.

关键词： 高加速度   离心加载   高加速度加载机   有限元模型   模态分析   共振   振型   大鼠   组织构建   加速度   生物力学   离心法   组织工程  

摘要： 背景:载人航天器发射与返回、舰载机的起飞与降落,会使航天员、飞行员处在高加速度(超重)环境中,高加速度环境会对细胞、器官、动物体等产生重要影响。高加速度离心加载机是一种可以为动物个体及细胞提供高加速度力学环境的装置,在航空航天的力学生物学、组织工程研究中起基础平台作用,目前通常生物学实验室需要高加速度加载装置。目的:结合现有离心机,设计制作大鼠高加速度离心加载机,研究大鼠在高加速度力学环境下的力学生物学响应。方法:离心机设计制作流程:确定设计参数、选择动力源→设计离心机结构并验证→选择制作控制器→加工制作机器并调试。对大鼠进行水平和竖直放置方向的加载,每个方向设置了4 G组、8 G组、10 G组、20 G组4个小组和一个对照组,观察不同高加速度环境对大鼠身体和行走能力的影响。结果与结论:①经过结构设计加工、配件选型和安装调试研制出高加速度加载机,设备包括机械结构与控制系统两部分;该机运行平稳,噪声低,平稳实现0-40 G的高加速度加载,并且还可实现变加速度加载;②采用该机对大鼠进行不同高加速度环境加载后,表现出身体向一侧倾斜,不能直线行走的现象,并且伴随战栗、后肢充血等症状,高加速度值越大,大鼠所受的影响越大,经过一段时间休息,大鼠身体基本可以恢复;③实验结果验证了该离心加载机可以为动物实验提供相应的高加速度环境,可以用于研究高加速度环境下动物的力学生物学响应。

关键词： African mole-rats   Subterranean life   Thermoregulation   Sociality   Energetics   Protection against temperature extremes  

摘要： African mole-rats are subterranean rodents, which rarely if ever leave the safety of their burrow systems. The environment of the burrows is humid, with relatively stable temperatures, and may have a hypoxic and hypercapnic atmosphere. One of crucial problems related to the subterranean way of life in mammals is avoidance of overheating, because traditional mammalian cooling mechanisms are not effective under high humidity. In African mole-rats, a variety of adaptations have evolved in response to this and other challenges of the underground ecotope. Traditionally, attention has been devoted mainly to the naked mole-rat Heterocephalus glaber, which became popular as a result of its eusociality and absence of fur, both being unique phenomena in small mammals. Despite more recent research, information on other species is still relatively limited and patchy. I review the results of studies on African mole-rats that are relevant for the understanding of their energetics and thermal biology. Attention is paid to the parameters of the burrow environment, which represent the main selection pressures shaping their physiology. In addition, an overview is given of the morphological, physiological and behavioural adaptations helping mole-rats to face temperature extremes, mechanisms by which they deal with a surplus of metabolic heat and how changes in ambient temperature influence their daily activity. The naked mole-rat is compared to its furred relatives to determine whether this species is really exceptional from the point of thermal biology. An ordination analysis was conducted using published data on mole-rat body temperature, thermoneutral zone, resting metabolic rate and thermal conductance. Most of the variability in these characteristics was found to be explained by body mass, followed by temperature characteristics of climate, but not precipitation, of the species distributional ranges. This analysis shows that the naked mole-rat is comparable to the other mole-rat