The Process-inducing Activity of Transmembrane Agrin Requires Follistatin-like Domains

Clustering or overexpression of the transmembrane form of the extracellular matrix proteoglycan agrin in neurons results in the formation of numerous highly motile filopodia-like processes extending from axons and dendrites. Here we show that similar processes can be induced by overexpression of transmembrane-agrin in several non-neuronal cell lines. Mapping of the process-inducing activity in neurons and non-neuronal cells demonstrates that the cytoplasmic part of transmembrane agrin is dispensable and that the extracellular region is necessary for process formation. Site-directed mutagenesis reveals an essential role for the loop between β-sheets 3 and 4 within the Kazal subdomain of the seventh follistatin-like domain of TM-agrin. An aspartic acid residue within this loop is critical for process formation. The seventh follistatin-like domain could be functionally replaced by the first and sixth but not by the eighth follistatin-like domain, demonstrating a functional redundancy among some follistatin-like domains of agrin. Moreover, a critical distance of the seventh follistatin-like domain to the plasma membrane appears to be required for process formation. These results demonstrate that different regions within the agrin protein are responsible for synapse formation at the neuromuscular junction and for process formation in central nervous system neurons and suggest a role for agrin''s follistatin-like domains in the developing central nervous system.     

On the role of ageing and musculoskeletal pain on dynamic balance in manual workers

The purpose of this study was to explore the interacting effects of age and musculoskeletal pain on balance in manual workers. Ninety male manual workers aged 51–72 yr were recruited and stratified according to lower extremity musculoskeletal pain intensity (pain/no pain) and work status (working/retired). The five-repetition sit-to-stand (STS) test was used to assess lower extremity function including completion time, stand time, sit time and dynamic rate of force development both in the upwards (RFD_up) and downwards moving phase (RFD_down). Dynamic balance was expressed as the range, velocity, standard deviation (SD), maximum Lyapunov Exponent and sample entropy of centre of pressure displacement in the anterior-posterior and medial-lateral direction, as well as free moment during the STS test. Except for higher age, no marked differences were seen between working and retired participants. Both age and musculoskeletal pain were negatively associated with motor function. Age × pain interactions showed that completion time, stand time, RFD_up and RFD_down were negatively associated with age for participants without pain, but positively for those with pain. Similar findings were seen for dynamic balance. These findings indicate that the effects of lower extremity musculoskeletal pain on lower extremity function and dynamic balance are age dependent.     

First record of Cisuralian–Guadalupian plant fossils from the Shan Plateau,eastern Myanmar

Permian plant fossils have never been reported from the Shan Plateau in eastern Myanmar. Recently, a black to gray carbonaceous mudstone unit containing abundant plant fossils was discovered just below the lowest part of Thitspin Limestone Formation from the Linwe Area, eastern Myanmar. Although only five taxa were identified, the plant assemblage provides the first evidence of the occurrence of Cathaysian elements in eastern Myanmar and potentially indicates the presence of a highly diverse Permian flora. Among the five species, Cordaites principalis and Annularia mucronata were cosmopolitan species; while Callipteridum cf. koraiense, Taeniopteris crassinervis Mo and Rhipidopsis lobata were mostly recorded in the Cathaysia Flora. Therefore, the present assemblage generally indicates a palaeobiogeographical affinity to the Cathaysian Province. Stratigraphically, Callipteridum cf. koraiense was mainly reported from Cisuralian to Wordian; whereas Taeniopteris crasssnervis Mo and Rhipidopsis lobata were recorded from Capitanian to Changhsingian, which suggests a general Permian age based on the plant assemblage itself only. However, the carbonaceous mudstone at the outcrop is overlain by the Thitspin Limestone Formation containing middle Guadalupian fusulinids. Based on previous faunal analyses, the Sibumasu terrane contains typical Gondwanan cold-water faunas during the early Cisuralian, warm-water faunas occurred after Sakmarian. Thus, age of the fossil-plant-containing carbonaceous mudstone is very likely between late Cisuralian and early Guadalupian as constrained by its overlying fusulinids and its warm Cathaysian palaeobiogeographical affinity.     

New latest Coniacian to middle Campanian foraminiferal data from the lower Zongshan Formation in the Chaqiela section,Gamba, southern Tibet

A first and detailed foraminiferal biostratigraphic work on the lower part of the Zongshan Formation (Limestone I and Calcareous Marl I sequence) in the Chaqiela section, Gamba, southern Tibet, allows the recognition of three latest Coniacian to middle Campanian planktic foraminiferal biozones: Dicarinella asymetrica Total Range Zone, Globotruncanita elevata Partial-Range Zone, and Contusotruncana plummerae Interval Zone. The base and top of the Santonian Stage in the Chaqiela section were placed at the lowest occurrence (LO) of Globotruncana linneiana and the highest occurrence (HO) of Dicarinella asymetrica, respectively. The deposition of the latest Coniacian to middle Campanian sediments of the lower Zongshan Formation in the Chaqiela section seems to have been continuous or at least without any major gap based on the planktic foraminiferal biozones and events.     

中国植被分类系统修订方案

为了推动《中国植被志》研编工作, 该文回顾了中国植被分类系统的发展过程和主要阶段性成果, 提出了作为《中国植被志》研编技术框架组成部分的中国植被分类系统修订方案, 对各植被型组及各植被型进行了简单定义和描述, 并针对中国植被分类系统若干问题, 特别就中国植被分类系统总体框架、混交林的界定以及土壤在植被分类中的重要性等问题进行了讨论。1960年侯学煜在《中国的植被》中首次提出了中国植被分类的原则和系统, 1980年出版的《中国植被》制定了分类等级和划分依据等更加完善的系统, 之后《中国植被及其地理格局——中华人民共和国1:1 000 000植被图说明书》和《中国植物区系与植被地理》以及很多省区的植被专著对该系统进行过修订。2017年宋永昌在《植被生态学》中提出了一个分类等级单位调整的方案。本次提出的中国植被分类系统修订方案基本沿用《中国植被》的植被分类原则、分类单位及系统, 采用“植物群落学-生态学”分类原则, 主要以植物群落特征及其与环境的关系作为分类依据, 包含三级主要分类单位, 即植被型(高级单位)、群系(中级单位)和群丛(低级单位); 在三个主要分类单位之上分别增加辅助单位植被型组、群系组和群丛组, 在植被型和群系之下主要根据群落的生态差异和实际需要可再增加植被亚型或亚群系。修订方案包含了森林、灌丛、草本植被(草地)、荒漠、高山冻原与稀疏植被、沼泽与水生植被(湿地)、农业植被、城市植被和无植被地段9个植被型组, 划分为48个植被型(含30个自然植被型、12个农业植被型、5个城市植被型和无植被地段)。自然植被中有23个植被型进一步划分出了81个植被亚型。     

Emsian (Lower Devonian) conodonts from the Daliantang Formation at Daliantang,southeastern Yunnan,China

The lower/upper Emsian boundary witnessed prominent diversification of biostratigraphically important genera Polygnathus Hinde, Caudicriodus Bultynck, and Latericriodus Müller. In contrast, conodonts previously reported around this boundary from the South China Block were characterized by relatively low species or subspecies diversity, and only a few widely distributed and extensively studied zone-defining taxa were recorded. In this paper, conodonts from the Daliantang Formation at the Daliantang section (Guangnan, southeastern Yunnan), one of the representative sections of the transitional facies between the benthic Xiangzhou facies and the pelagic Nandan facies, are investigated. The conodont fauna shows a remarkably high species or subspecies diversity, with fourteen taxa that are assignable to the notoperbonus Zone and inversus Zone. Five polygnathid species are described: P. gronbergi Klapper and Jonson, P. inversus Klapper and Jonson, Polygnathus sp. B, P. luciae Martínez-Pérez and Valenzuela-Ríos, and P. mashkovae Bardashev. The latter two are reported for the first time from the South China Block. Additionally, three icriodontid taxa are also described, of which L. guangnanensis n. sp. is characterized by distinctly chevron-shaped transverse rows in the anterior part and a well-developed process branching off to the outer side. The new conodont record increases our understanding of the diversification and faunal composition around the lower/upper Emsian boundary in the South China Block. It contributes to the regional and inter-regional biostratigraphical correlation between shallower- and deeper-water facies and also furnishes important South China material for future discussion and deliberation on the position of the lower/upper Emsian boundary.     

Lower Jurassic corals from the Pamir Mountains,Central Asia

The paper describes new Lower Jurassic corals from the South-Eastern Pamir Mountains (Tajikistan) and interprets their relationships with contemporaneous West Tethyan corals. Taxonomic similarities with Pliensbachian European and North African faunas indicate a Pliensbachian age for this fauna, which was previously considered to be of Hettangian/Sinemurian age. Together with the taxa earlier described from the Pamirs, this fauna consists of 30 species of 25 genera, including Triassic holdover genera such as Stylophyllopsis, Phacelostylophyllum and Eocomoseris. The bulk of the fauna represents new Jurassic genera: Alichurastrea, Eomicrophyllia, Guembelastreomorpha, Gurumdynia, Pinacomorpha, Protostephanastrea, Psenophyllia, Sedekastrea and Stylimorpha. Earlier coral studies of the region concerned the genera: Archaeosmilia Melnikova, 1975, Archaeosmiliopsis Melnikova, 1975, Cylismilia Roniewicz, 1988, Pachysmilia Melnikova, 1989, and Prodonacosmilia Melnikova in Melnikova and Roniewicz, 1976. Two species that were considered to belong to the genus Cylismilia, are redescribed and reclassified in the genera Psenophyllia, and Archaeosmilia Melnikova, respectively.     

New fossil genus and species of carrion beetle (Coleoptera,Silphidae) from the Lower Cretaceous Jinju Formation,South Korea

A new fossil genus of Silphidae, Cretosaja gen. nov., is described, based on a new fossil species, Cretosaja jinjuensis sp. nov. from the Lower Cretaceous Jinju Formation in South Korea. The association of Cretosaja with Nicrophorinae is discussed on the basis of morphological evidence. Diagnostic differences of the fossil and extant genera of Nicrophorinae are provided. Primitive characteristics presented in Mesozoic silphids are discussed.     

2型糖尿病患者血糖波动与心律失常和下肢血管病变的关系及其影响因素分析

目的:探讨2型糖尿病(T2DM)患者血糖波动与心律失常和下肢血管病变的关系,分析影响T2DM心律失常和下肢血管病变的因素。方法:选择2019年7月到2020年6月我院收治的82例T2DM患者,根据是否合并心律失常分为心律失常组28例和无心律失常组54例,根据是否合并下肢血管病变分为下肢血管病变组31例和无下肢血管病变组51例。所有患者均通过72 h监测血糖获得日内平均血糖波动幅度(MAGE)、日间血糖平均绝对差(MODD)、全天血糖标准差(SDBG)、全天血糖波动次数(NGE)。比较组间差异,分析影响T2DM患者心律失常和下肢血管病变的因素。结果:心律失常组MAGE、MODD、SDBG、NGE、糖化血红蛋白(HbA1c)、胰岛素抵抗指数(HOMA-IR)、T2DM病程、同型半胱氨酸(Hcy)、丙二醛(MDA)高于无心律失常组(P<0.05)。下肢血管病变组T2DM病程、Hcy、MDA、HOMA-IR、MAGE、MODD、SDBG、NGE均高于无下肢血管病变组(P<0.05)。Logistic回归分析结果显示MDA、HOMA-IR、MAGE、MODD是T2DM患者心律失常的危险因素(P<0.001),MAGE、MODD、SDBG是T2DM患者下肢血管病变的危险因素(P<0.001)。结论:T2DM患者血糖波动与心律失常和下肢血管病变均有关,血糖波动增加是T2DM心律失常和下肢血管病变的危险因素。     

Isaac Lea's Palaeosauropus (= “Sauropus”) primaevus: A Review of His Discovery

In 1849, Isaac Lea named Sauropus primaevus for footprints from Mount Carbon, Pennsylvania, USA, then the oldest fossil vertebrate footprints reported. In 1902, O. P. Hay constructed a new ichnogenus Palaeosauropus for this ichnospecies. Palaeosauropus has been one of the most frequently reported Mississippian footprint ichnogenera in North America and remains a valid ichnotaxon. The holotype of Palaeosauropus (= “Sauropus”) primaevus (referred to as P. primaevus), consisting of a single manus/pes pair, is described and illustrated in Lea (1853) Lea, I. 1853. On the fossil foot-marks in the Red Sandstones of Pottsville, Schuylkill County, Penna. Transactions of the American Philosophical Society, 10(new series): 307–315.  [Google Scholar] and is housed at the Academy of Natural Sciences in Philadelphia, Pennsylvania (ANS9752). Lea's large specimen of P. primaevus (approximately 86 cm by 53 cm), that included a trackway of six manus/pes pairs, described and illustrated in 1853 and 1855, was a combination of ANS9752 and a second specimen represented by a plaster cast housed at the National Museum of Natural History (USNM487148). Historical documents and examination of the Mauch Chunk Formation at Mount Carbon, Pennsylvania, enabled the identification of Lea's tracksite, originally reported to be a few hundred feet (about 75 m) from the former Mount Carbon Hotel. Our forensic evidence indicates the type locality for P. primaevus is approximately 90 m south from the southwest corner of Centre and Main Streets in Mount Carbon, Pennsylvania, with geographical coordinates of N 40° 40' 25.7”, W 76° 11' 14.9”. The type locality is within the middle member of the Mauch Chunk Formation, a fluvial sequence of late Mississippian (Visean) Age.