Preservation, Biological

PRESERVATION,生物学
  • 文章类型: Systematic Review
    孢子丝菌病是由孢子丝菌属真菌引起的皮下真菌病。表型和基因型差异与它们的地理分布有关,毒力,或孢子丝菌病的临床表现。在过去的十年里,对鉴定孢子丝菌物种的兴趣。一直在增加,由于其流行病学的重要性和,因此,知道如何保存它们以备将来研究很重要,文化收藏
    本研究的目的是分析通过多相分类法鉴定的孢子丝菌病的环境分离物和/或致病因子的全球分布,强制使用分子鉴定,并评估培养物集合中储存的分离株的百分比和分布。
    关于动物和人类孢子丝菌病和/或真菌环境隔离的文章的系统综述,从2007年到2023年,已经完成。结果:我们的研究结果表明,S、globosa,S.申克,巴西链球菌是鉴定最多的物种。关于物种的存放和维护,我们观察到只有17%的孢子丝菌。与世隔绝,保存在文化收藏中。
    这项系统评价证实了难以获得培养物中存储的孢子丝菌物种的频率,并且有关主要是动物孢子丝菌病的分子鉴定和孢子丝菌的分离的数据不足。在环境样本中。
    UNASSIGNED: Sporotrichosis is a subcutaneous mycosis caused by fungi of the genus Sporothrix sp. Phenotypic and genotypic differences have been associated with their geographic distribution, virulence, or clinical manifestation of sporotrichosis. In the past decade, the interest in identifying species of the Sporothrix sp. has been increasing, due to its epidemiological importance and, in consequence, is important to know how to preserve them for future studies, in culture collection.
    UNASSIGNED: The purposes of this study were to analyze the global distribution of environmental isolates and/or causal agents of sporotrichosis identified by polyphasic taxonomy, with mandatory use of molecular identification, and to evaluate the percentages and distribution of isolates stored in culture collections.
    UNASSIGNED: A systematic review of articles on animal and human sporotrichosis and/or environmental isolation of the fungus, from 2007 to 2023, was done. Results: Our results demonstrated that, S. globosa, S. schenckii, and S. brasiliensis were the most identified species. With respect to the deposit and maintenance of species, we observed that only 17% of the strains of Sporothrix sp. isolated in the world are preserved in a culture collection.
    UNASSIGNED: This systematic review confirmed a difficulty in obtaining the frequency of Sporothrix species stored in culture collection and insufficient data on the molecular identification mainly of animal sporotrichosis and isolation of Sporothrix sp. in environmental samples.
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  • 文章类型: Journal Article
    脊椎动物身体或其部分的印象,比如化石和骨头的天然霉菌,是有关古代动物区系的宝贵信息来源,可以补充基于骨骼元素的标准化石记录。尽管动物活动的痕迹化石在物学领域相对普遍且研究活跃,和内部或外部表面的自然印象是化石无脊椎动物的常见保存模式,骨头的自然霉菌比较罕见,文献记载和讨论较少。其中,龟壳的内部模具(Steinkerns)是一种相对众所周知的保存形式,但是导致其形成的机制和植物学先决条件研究甚少。外壳体模具在文献中的代表性更低。在这里,我们描述了来自德国三叠纪(Norian)Löwenstein地层的天然外部海龟plastron霉菌的历史标本,该地层也产生了许多海龟steinkerns。标本之所以重要,不仅是因为它代表了一种不寻常的保存形式,但也由于其非常大的尺寸和潜在的外壳病理的存在。尽管最初被解释为Proterochersissp。,最近对海龟的认识取得了进展,导致该群体中已知分类群的数量增加,这使我们能够验证这一评估。我们确认该标本在形态上与该属一致,并初步将其鉴定为Proterochersisrobusta,该属的唯一代表来自Löwenstein组。我们注意到,然而,它的大小超过了迄今为止在Proterochersisrobusta中观察到的大小,并且符合波兰Grabowa组的Proterochersisporebeensis的范围。被解释为外壳病理学的标记在形态上与Karethraichhnuslakkos一致-一种被解释为外寄生虫的ichnotaxon,比如水蛭。这可能支持先前提出的对Proterochersisspp的解释。像半水生乌龟。此外,如果鉴定正确,该标本可能代表一个非常罕见的病例,即一个命名的ichnotaxon阴性保存。最后,我们讨论了Löwenstein地层海龟与其他三叠纪海龟产生的地层相比,这些地层没有显示出保存内部或外部壳霉菌的潜力,并提出了形成此类化石的解剖学模型。
    Impressions of vertebrate bodies or their parts, such as trace fossils and natural molds of bones, are a valuable source of information about ancient faunas which may supplement the standard fossil record based on skeletal elements. Whereas trace fossils of animal activity are relatively common and actively studied within the field of ichnology, and natural impressions of internal or external surfaces are a frequent preservation mode in fossil invertebrates, natural molds of bones are comparatively rare and less extensively documented and discussed. Among them, internal molds (steinkerns) of turtle shells are a relatively well-known form of preservation, but the mechanisms and taphonomic prerequisites leading to their formation are poorly studied. External shell molds are even less represented in the literature. Herein, we describe a historic specimen of a natural external turtle plastron mold from the Triassic (Norian) Löwenstein Formation of Germany-a formation which also yielded a number of turtle steinkerns. The specimen is significant not only because it represents an unusual form of preservation, but also due to its remarkably large size and the presence of a potential shell pathology. Although it was initially interpreted as Proterochersis sp., the recent progress in the knowledge of proterochersid turtles leading to an increase in the number of known taxa within that group allows us to verify that assessment. We confirm that the specimen is morphologically consistent with the genus and tentatively identify it as Proterochersis robusta, the only representative of that genus from the Löwenstein Formation. We note, however, that its size exceeds the size observed thus far in Proterochersis robusta and fits within the range of Proterochersis porebensis from the Grabowa Formation of Poland. The marks interpreted as shell pathology are morphologically consistent with Karethraichnus lakkos-an ichnotaxon interpreted as a trace of ectoparasites, such as leeches. This may support the previously proposed interpretation of Proterochersis spp. as a semiaquatic turtle. Moreover, if the identification is correct, the specimen may represent a very rare case of a negative preservation of a named ichnotaxon. Finally, we discuss the taphonomy of the Löwenstein Formation turtles in comparison with other Triassic turtle-yielding formations which show no potential for the preservation of internal or external shell molds and propose a taphonomic model for the formation of such fossils.
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  • 文章类型: Journal Article
    提高水果的保质期是具有挑战性的。生物可降解多糖普鲁兰表现出优异的成膜能力,气体阻隔性能,和自然可分解性,使其成为水果保鲜的最佳材料。为了克服现有包装技术的高成本和薄膜孔隙率的问题,我们旨在开发基于普鲁兰的包装纸,以提高水果的保质期。一种薄纸涂层,其包含15重量%的混合物。%的普鲁兰溶液在各种标准粘度(75.6,77.8和108.5mPa·s)与茶多酚(15:2)和/或维生素C(150:1)改善了氧气透过率(120-160cm3m-2·24h·0.1MPa),水蒸气透过率(<5.44g·mm-1m-2·h·kPa),最大自由基清除率(>87%),基础包装纸的抗菌性能。与对照葡萄(包裹在未处理/原纸中)相比,用这些基于支链淀粉的纸包裹的葡萄在储存10天后表现出较少的重量损失(>4.41%)和改善的硬度(>16.4%)。用基于普鲁兰的纸包裹的葡萄的重量>12.6。%总可溶性固形物,>1.5mg/g可溶性蛋白质,>0.44wt。可滴定酸度%,和≥4.5毫克100克-1抗坏血酸。因此,支链淀粉纸可以延长葡萄的保质期,操作方便,为水果保存提供巨大的价值。
    Improving the shelf lives of fruits is challenging. The biodegradable polysaccharide pullulan exhibits excellent film-forming ability, gas barrier performance, and natural decomposability, making it an optimal material for fruit preservation. To overcome problems of high cost and film porosity of existing packaging technologies, we aimed to develop pullulan-based packaging paper to enhance the shelf lives of fruits. A thin paper coating comprising a mixture of 15 wt.% pullulan solution at various standard viscosities (75.6, 77.8, and 108.5 mPa·s) with tea polyphenols (15:2) and/or vitamin C (150:1) improved the oxygen transmission rate (120-160 cm3 m-2·24 h·0.1 MPa), water vapor transmission rate (<5.44 g·mm-1 m-2·h·kPa), maximum free radical clearance rate (>87%), and antibacterial properties of base packaging paper. Grapes wrapped with these pullulan-based papers exhibited less weight loss (>4.41%) and improved hardness (>16.4%) after 10 days of storage compared to those of control grapes (wrapped in untreated/base paper). Grapes wrapped with pullulan-based paper had >12.6 wt.% total soluble solids, >1.5 mg/g soluble protein, >0.44 wt.% titratable acidity, and ≥4.5 mg 100 g-1 ascorbic acid. Thus, pullulan-based paper may prolong the shelf life of grapes with operational convenience, offering immense value for fruit preservation.
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  • 文章类型: Journal Article
    许多生物分子缩合物富含并依赖于RNA和RNA结合蛋白(RBP)。到目前为止,只有少数研究解决了负责液-液相分离(LLPS)的分子间相互作用的表征以及缩合对RBP和RNA的影响。这里,我们提出了一种通过将同位素标记的RNA的交联和串联质谱应用于相分离系统(LLPS-CLIR-MS)来研究生物分子缩合物中蛋白质-RNA相互作用的方法。LLPS-CLIR-MS能够以残基特异性分辨率表征生物分子缩合物中存在的分子间相互作用,并允许与分散相中的相同复合物进行比较。我们观察到存在于分散相中的序列特异性RBP-RNA相互作用通常保持在缩合物内。此外,LLPS-CLIR-MS鉴定蛋白质-RNA界面的结构改变,包括冷凝相中的额外非特异性接触。我们的方法提供了一种程序来获取生物分子缩合物中蛋白质-RNA复合物的结构信息,这对于这种形式的核糖核蛋白(RNP)的整合结构建模至关重要。
    Many biomolecular condensates are enriched in and depend on RNAs and RNA binding proteins (RBPs). So far, only a few studies have addressed the characterization of the intermolecular interactions responsible for liquid-liquid phase separation (LLPS) and the impact of condensation on RBPs and RNAs. Here, we present an approach to study protein-RNA interactions inside biomolecular condensates by applying cross-linking of isotope labeled RNA and tandem mass spectrometry to phase-separating systems (LLPS-CLIR-MS). LLPS-CLIR-MS enables the characterization of intermolecular interactions present within biomolecular condensates at residue-specific resolution and allows a comparison with the same complexes in the dispersed phase. We observe that sequence-specific RBP-RNA interactions present in the dispersed phase are generally maintained inside condensates. In addition, LLPS-CLIR-MS identifies structural alterations at the protein-RNA interfaces, including additional unspecific contacts in the condensed phase. Our approach offers a procedure to derive structural information of protein-RNA complexes within biomolecular condensates that could be critical for integrative structural modeling of ribonucleoproteins (RNPs) in this form.
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  • 文章类型: Journal Article
    准确的最小验尸间隔(minPMI)估计通常依赖于昆虫发育阶段的精确年龄确定,受环境温度的影响很大。在犯罪现场收集的昆虫学样品的最佳保存对于未成熟昆虫样品的可靠老化至关重要。对于苍蝇(双翅目:Calliphoridae),法医调查中使用最广泛的昆虫指标,在阴部样本的情况下,组织的适当保存尤为重要,因为阴部内部形式的老化方法通常取决于形态学分析;然而,尽管如果没有正确固定,信息丰富的软组织和结构可能会变色和/或变形,缺乏研究来评估法医调查中收集的阴部内部形式的最佳保存的不同方法。本研究比较了三种保存方法,以保存pay蝇CalliphoravicinaRobineau-Desvoidy的阴部形式,1830:(i)直接浸入80%乙醇中,(ii)在保存在80%乙醇中之前,刺破脓毒和热水杀灭(HWK),和(iii)在80%乙醇中保存之前未刺穿的HWK。对不同年龄的阴部形式进行了外部和内部形态分析,以评估保存质量。结果表明,直接浸入乙醇会导致保存不良,影响外部和内部组织。HWK的两种方法都能更好地保存,但是穿刺结果,在某些情况下,在标本的物理损伤中。不穿刺的HWK成为最佳保存方法,对于外部和内部形态分析,始终产生较高的保存分数。这些发现对法医从业人员具有实际意义,并强调需要更新一些已发布的法医昆虫学指南和协议。
    Accurate minimum post-mortem interval (minPMI) estimations often rely on a precise age determination of insect developmental stages, which is significantly influenced by environmental temperature. An optimal preservation of the entomological samples collected at crime scenes is pivotal for a reliable aging of immature insect samples. For blow flies (Diptera: Calliphoridae), the most widely used insect indicators in forensic investigations, an appropriate preservation of tissues is particularly important in the case of puparial samples because aging methods for intra-puparial forms usually depend on morphological analyses; however, although informative soft tissues and structures could be discoloured and/or distorted if they are not properly fixed, there is a lack of studies to assess different methods for the optimal preservation of intra-puparial forms collected in forensic investigations. The present study compares three preservation methods for intra-puparial forms of the blow fly Calliphora vicina Robineau-Desvoidy, 1830: (i) direct immersion into 80% ethanol, (ii) puncturing of the puparium and hot water killing (HWK) prior to preservation in 80% ethanol, and (iii) HWK without puncturing before preservation in 80% ethanol. External and internal morphological analyses of intra-puparial forms of different ages were conducted to assess the quality of preservation. The results indicate that direct immersion in ethanol led to poor preservation, affecting both external and internal tissues. Both methods with HWK resulted in a better preservation, but puncturing resulted, in some cases, in physical damage of the specimens. HWK without puncturing emerged as the optimal preservation method, consistently yielding high preservation scores for both external and internal morphological analyses. These findings have practical implications for forensic practitioners and emphasise the need for updating some published guidelines and protocols in forensic entomology.
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  • 文章类型: Journal Article
    肝细胞癌(HCC)是最常见的原发性肝癌,and,随着对肿瘤免疫微环境(TIME)研究的增加,肝癌的免疫抑制微环境阻碍了免疫治疗的进一步应用,尽管免疫治疗可以为晚期肝癌患者提供生存益处。目前的研究表明,多胺代谢不仅是肿瘤相关巨噬细胞(TAMs)形成免疫抑制表型的关键代谢途径,但它也深刻地参与线粒体质量控制信号和能量代谢调节过程,因此进一步研究多胺代谢在肿瘤微环境(TME)中的作用尤为重要。在这次审查中,通过总结目前多胺代谢途径中调节TAMs和T细胞的关键酶和底物的研究进展,我们认为多胺生物合成可以通过影响线粒体自噬来干预线粒体能量代谢过程,which,反过来,调节巨噬细胞极化和T细胞分化。多胺代谢可能是HCC细胞和免疫细胞如TAM之间互动对话的关键目标。因此,干扰多胺代谢可能成为破坏细胞间通讯的重要切入点,为开发基于多胺代谢的HCC治疗提供新的研究空间。
    Hepatocellular carcinoma (HCC) is the most common primary liver cancer, and, with increasing research on the tumor immune microenvironment (TIME), the immunosuppressive micro-environment of HCC hampers further application of immunotherapy, even though immunotherapy can provide survival benefits to patients with advanced liver cancer. Current studies suggest that polyamine metabolism is not only a key metabolic pathway for the formation of immunosuppressive phenotypes in tumor-associated macrophages (TAMs), but it is also profoundly involved in mitochondrial quality control signaling and the energy metabolism regulation process, so it is particularly important to further investigate the role of polyamine metabolism in the tumor microenvironment (TME). In this review, by summarizing the current research progress of key enzymes and substrates of the polyamine metabolic pathway in regulating TAMs and T cells, we propose that polyamine biosynthesis can intervene in the process of mitochondrial energy metabolism by affecting mitochondrial autophagy, which, in turn, regulates macrophage polarization and T cell differentiation. Polyamine metabolism may be a key target for the interactive dialog between HCC cells and immune cells such as TAMs, so interfering with polyamine metabolism may become an important entry point to break intercellular communication, providing new research space for developing polyamine metabolism-based therapy for HCC.
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  • 文章类型: Journal Article
    射血分数(HFpEF)保留的心力衰竭(HF)是一种日益频繁的形式,估计是HF的主要形式。另一方面,HFpEF是一种全身受累的综合征,它的特征是多种心脏和心外病理生理改变。日益增加的流行率目前已达到流行水平,从而使HFpEF成为当今心血管医学面临的最大挑战之一。与射血分数(HFrEF)降低的HF相比,HFpEF病例的医疗态度是对疾病的放松,尽管事实要复杂得多,与确定生理病理机制和最佳治疗方法有关的许多问题。当前的医学挑战是制定有效的治疗策略,因为患有HFpEF的患者的症状和生活质量与射血分数降低的患者相当,但是HFrEF的特定药物在这种情况下无效;为此,我们必须首先详细了解病理机制,并将其与临床表现联系起来。HFpEF的另一个重要方面是可以在该综合征的保护伞下识别的患者的多样性。因此,在能够测试和开发有效的疗法之前,我们必须把病人分成几类,称为表型,取决于病理途径和临床特征。这篇叙事评论批评了与定义相关的问题,病因学,临床特征,和HFpEF的病理生理学。我们试图尽可能详细地描述文献中公认的临床和生物学表型,以便更好地了解当前的治疗方法和有效性有限的原因。我们还强调了该领域最新研究可以靶向的可能的病理途径。
    Heart failure (HF) with preserved ejection fraction (HFpEF) is an increasingly frequent form and is estimated to be the dominant form of HF. On the other hand, HFpEF is a syndrome with systemic involvement, and it is characterized by multiple cardiac and extracardiac pathophysiological alterations. The increasing prevalence is currently reaching epidemic levels, thereby making HFpEF one of the greatest challenges facing cardiovascular medicine today. Compared to HF with reduced ejection fraction (HFrEF), the medical attitude in the case of HFpEF was a relaxed one towards the disease, despite the fact that it is much more complex, with many problems related to the identification of physiopathogenetic mechanisms and optimal methods of treatment. The current medical challenge is to develop effective therapeutic strategies, because patients suffering from HFpEF have symptoms and quality of life comparable to those with reduced ejection fraction, but the specific medication for HFrEF is ineffective in this situation; for this, we must first understand the pathological mechanisms in detail and correlate them with the clinical presentation. Another important aspect of HFpEF is the diversity of patients that can be identified under the umbrella of this syndrome. Thus, before being able to test and develop effective therapies, we must succeed in grouping patients into several categories, called phenotypes, depending on the pathological pathways and clinical features. This narrative review critiques issues related to the definition, etiology, clinical features, and pathophysiology of HFpEF. We tried to describe in as much detail as possible the clinical and biological phenotypes recognized in the literature in order to better understand the current therapeutic approach and the reason for the limited effectiveness. We have also highlighted possible pathological pathways that can be targeted by the latest research in this field.
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  • 文章类型: Journal Article
    引入鱼皮作为治疗烧伤和伤口的生物敷料具有很大的前景,提供现有管理策略的替代方案。然而,疾病传播的风险是一个重大问题。因此,这项研究旨在研究已建立的灭菌和保存程序如何影响长期使用的鱼皮移植物的微生物学和组织学特性。鱼皮移植物的冻干,然后在生理盐水中再水化15分钟并没有改变胶原蛋白的含量。此外,不同长度5、10和25KGy的冻干鱼皮移植物的γ辐照显示微生物生长显着减少(需氧细菌,有氧酵母,和真菌)在辐照后15天和30天。然而,在不同的伽玛辐照长度中,暴露于10KGy是最有效的强度,因为它在辐照后15天和30天保留了冻干鱼皮移植物中的胶原纤维含量和强度。这些发现为长期使用用于生物敷料的新鲜罗非鱼皮肤移植物提供了有效的保存和灭菌方法。
    The introduction of fish skin as a biological dressing for treating burns and wounds holds great promise, offering an alternative to existing management strategies. However, the risk of disease transmission is a significant concern. Therefore, this study aimed to examine how established sterilization and preservation procedures affected fish skin grafts\' microbiological and histological properties for long-term usage. Lyophilization of the fish skin graft followed by rehydration in normal saline for 15 min did not change the collagen content. Furthermore, gamma irradiation of the lyophilized fish skin graft at different lengths 5, 10, and 25 KGy showed a significant reduction in microbial growth (aerobic bacteria, aerobic yeasts, and fungi) at 15- and 30 days after the irradiation. However, exposure to 10 KGy was found to be the most effective intensity among the different gamma irradiation lengths since it preserved the collagen fiber content and intensity in the lyophilized fish skin grafts at 15- and 30 days after the irradiation. These findings provide efficient preservation and sterilization methods for long-term usage of the fresh Tilapia skin grafts used for biological dressings.
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  • 文章类型: Journal Article
    心力衰竭是一种与生活质量差相关的临床综合征,大量的医疗资源利用,过早死亡,在很大程度上与高住院率有关。无论射血分数如何,心力衰竭的临床表现都相似。与射血分数降低的心力衰竭不同,射血分数保留的心力衰竭治疗方案很少.在射血减少的心力衰竭中显示出降低的死亡率和发病率的分子疗法尚未被证明对患有心力衰竭和保留射血分数的患者有效。对射血分数保留的心力衰竭产生过程中涉及的病理生理过程的研究是确定新的治疗手段的基础。在这篇叙述性评论中,我们打算综合现有的治疗手段,但也是那些在研究(代谢和microRNA治疗)的心脏衰竭保留射血分数的治疗。
    Heart failure is a clinical syndrome associated with poor quality of life, substantial healthcare resource utilization, and premature mortality, in large part related to high rates of hospitalizations. The clinical manifestations of heart failure are similar regardless of the ejection fraction. Unlike heart failure with reduced ejection fraction, there are few therapeutic options for treating heart failure with preserved ejection fraction. Molecular therapies that have shown reduced mortality and morbidity in heart failure with reduced ejection have not been proven to be effective for patients with heart failure and preserved ejection fraction. The study of pathophysiological processes involved in the production of heart failure with preserved ejection fraction is the basis for identifying new therapeutic means. In this narrative review, we intend to synthesize the existing therapeutic means, but also those under research (metabolic and microRNA therapy) for the treatment of heart failure with preserved ejection fraction.
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  • 文章类型: Journal Article
    化石记录中种间相互作用的证据很少见,但为古代生态学提供了宝贵的见解。特殊的化石遗址可以保留涉及非生物矿化生物的复杂生态相互作用,但是这些例子中的大多数仅限于寒武纪Lagerstätten。在这里,我们报告了来自摩洛哥Tremadocian年龄的下Fezouata页岩地层的异常保存的跨门种间相互作用,它由直角型头足类的phragmocone组成,该头足类在死后被管状表皮广泛填充。保存完好的锯齿形横向带和沿无分支管边缘的锯齿形断口表明它们对应于翼龙半黄体,基于密集的tubarium的灌木状生长,与横纹肌的形态相似。在Fezouata页岩中发现的横纹肌样表皮突出了底栖石墨岩的匮乏,其中还包括生根的树枝状植物Didygraptus和Dictyonema,相对于从该生物群中已知的更加多样化和丰富的浮游生物形式。我们认为,古生代横纹肌的稀有性很可能是它们对硬基质进行初始沉降和生长的生态需求的结果。Fezouata横纹肌还揭示了一种具有4.8亿年历史的翼龙属软体动物的外生体,一直持续到今天。
    Evidence of interspecific interactions in the fossil record is rare but offers valuable insights into ancient ecologies. Exceptional fossiliferous sites can preserve complex ecological interactions involving non-biomineralized organisms, but most of these examples are restricted to Cambrian Lagerstätten. Here we report an exceptionally preserved cross-phylum interspecific interaction from the Tremadocian-aged Lower Fezouata Shale Formation of Morocco, which consists of the phragmocone of an orthocone cephalopod that has been extensively populated post-mortem by tubicolous epibionts. Well-preserved transverse bands in a zig-zag pattern and crenulations along the margin of the unbranched tubes indicate that they correspond to pterobranch hemichordates, with a close morphological similarity to rhabdopleurids based on the bush-like growth of the dense tubarium. The discovery of rhabdopleurid epibionts in the Fezouata Shale highlights the paucity of benthic graptolites, which also includes the rooted dendroids Didymograptus and Dictyonema, relative to the substantially more diverse and abundant planktic forms known from this biota. We propose that the rarity of Paleozoic rhabdopleurid epibionts is likely a consequence of their ecological requirement for hard substrates for initial settlement and growth. The Fezouata rhabdopleurid also reveals a 480-million-year-old association of pterobranchs as epibionts of molluscs that persist to the present day.
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