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Progress in Natural Science:Materials International 2006年第4期16卷 373-378页

作者： alan warren Department of Zoology The Natural History Museum Cromwell Road London SW7 5BD UK

The small subunit rRNA (SSrRNA) gene was sequenced for two marine scuticociliates Metanophrys similis and Pseudocohnilembus hargisi. The results show that this gene comprises 1763 and 1753 nucleotides in the two marine ciliates respectively. Metanophrys similis is phylogenetically closely related to the clade containing Mesanophrys carcini and Anophyroides haemophila, which branches basally to other species within the order Philasterida. Pseudocohnilembus hargisi groups with its congener, P. marinus, with strong bootstrap support. Paranophrys magna groups with the clade including Cohnilembus and Uronema, representing a sister clade to that containing the two Pseudocohnilembus species.

关键词： phytogeny protozoa scuticociliate Metanophrys similis Pseudocohnilembus hargisi.

Re-evaluation of the phylogenetic position of the genus Dexiotrichides (Protozoa, Ciliophora, Scuticociliatida) inferred from stomatogenetic and molecular information for Dexiotrichides pangi

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Progress in Natural Science:Materials International 2005年第8期15卷 700-707页

作者： alan warren,David ROBERTS,Norbert WILBERT London SW7 5BD UK Zoologisches Institut Universitt Bonn 53115 Bonn Germany Department of Zoology Natural History of Museum Cromwell Road London SW7 5BD UK Department of Zoology Natural History of Museum Cromwell Road

The divisional process and systematic position of the marine scuticociliate Dexiotrichides pangi are studied. Based on both stomatogenetic data and 18S rDNA gene sequences, the phylogeny and morphogenetic characteristics of this taxon, and of other related genera, are analyzed and discussed. Both the divisionary events and the molecular biological data indicate that this species/genus, together with certain other genera in the Dexiotricha-complex, occupies an intermediate position between the tetrahymenids and the “typical” scuticociliate, which suggests that the Dexiotricha-like taxa should be excluded from the “true” scuticociliates. As a further contribution, the process of stomatogenesis in D. pangi can be summarized as follows: (1) The oral primordia in the opisthe are formed only by the proliferation of basal bodies in the scutica field, which subsequently develop into three membranelles, while the new paroral membrane seems to be generated by the sub-anterior portion of somatic kinety 1 (the 1st postoral intercalary kinety). The latter character exhibits a mode similar to Tetrahymena. (2) In the proter the parental membranelles are retained and remain unchanged throughout the entire division process; only the old paroral membrane is disassembled and differentiated into the anlage, which then gives rise to the new paroral membrane and the scutica of the proter. The 18S rRNA gene sequence reported here is the first one for a ciliate in the Dexiotricha-complex.

关键词： marine ciliate systematic position stomatogenesis 18S rRNA gene sequences Dexiotrichides pangi.

A Bioassay for the Cytotoxicity of Gemcitabine Using the Marine Ciliate Euplotes vannus

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Journal of Ocean University of China 2019年第3期18卷 675-679页

作者： WANG Qi XU Henglong warren alan Department of Urology Surgery Qingdao Municipal Hospital Group Qingdao 266000 China College of Marine Life Science Ocean University of China Qingdao 266003 China Department of Life Sciences Natural History Museum London SW7 5BD UK

This study investigated the cytotoxicity of gemcitabine using the marine ciliate Euplotes vannus as the test *** median lethal concentrations(LC50 values)were determined using acute toxicity tests within an exposure time of 30 min with 0,6,12,24,and 48 mg mL^-1 *** median inhibition effect(IC50 value)on the growth of the ciliate cells was examined using chronic toxicity tests within 5 days(120 h)after exposure for 30 min with 0,0.7,3.5,7,and 14 mg mL^-1 *** 30-min LC50value was 10.66-mg mL *** LC50 values decreased with increasing exposure times and well fitted to the toxicity curve equation LC50=10.93+28.4e^-0.19t(R2=0.93;P<0.05,t=exposure time).The IC50 value for growth rates was 7.05 mg mL^-1,and the inhibition effect on growth rates well fitted to the model equation r%=0.8681e^-0.0782Cgem(r%means growth rate with inhibition by gemcitabine,Cgem means concentrations of gemcitabine,R^2=0.99 and P<0.05).The LC50 values of a wide range of gemcitabine concentrations could therefore be predicted for any given exposure *** results suggest that the clinical dose of gemcitabine(20 mg mL^-1)was higher than the 30-min LC50 value,which was almost the same as the 6-min LC50 value(19.88 mg mL^-1)for *** *** results also demonstrate that *** can be used as a robust test organism for bioassays of chemotherapeutic drugs during short exposure periods.

关键词： bioassay cytotoxicity Euplotes vannus gemcitabine toxicology

Distribution of Protists in the Deep South China Sea Revealed by High-Throughput Sequencing

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Journal of Ocean University of China 2020年第1期19卷 161-170页

作者： LI Xinran warren alan JIAO Nianzhi XU Dapeng State Key Laboratory of Marine Environmental Science Institute of Marine Microbes and EcospheresCollege of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Department of Life Sciences Natural History MuseumLondonSW75BDUK

Protists(microbial eukaryotes)are indispensable members of the marine microbial food *** recent years,organisms living in the deep sea(>1000 m water depth)have increasingly become the focus of research;however,studies on protistan assemblages are relatively scarce compared with their prokaryotic *** the present study,high-throughput sequencing of the hypervariable V9 region of the 18S rRNA gene was used to explore the community composition of protists in bathypelagic waters of the South China *** on the analysis of the alpha and beta diversities of 14 samples,we discovered:1、members belonging to Rhizaria,Alveolata,and Excavata were the dominant groups in terms of both relative sequence abundance and operational taxonomic unit(OTU)richness in all samples,although their relative contributions differed among different samples;2、cluster analysis showed that the distribution of protistan assemblages was related neither to the sampling location nor to the water depth,and other environmental factors might have caused the differences among the communities;3、phototrophs,including members of the Bacillariophyta,Bolidophyceae,Dictyochophyceae,Prasinophyceae,and Prymnesiophyceae,were detected in all samples,which indicated their contributions to the downward transportation via the biological pump and the potential presence of phagotrophy of these phototrophic cells in the deep ocean.

关键词： bathypelagic water diversity microbial eukaryotes SSU rRNA gene

Toxicity of Chlorpyrifos and Dimethoate to the Ciliate Urostyla grandis, with Notes on Their Effects on Cell Ultrastructure

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Journal of Ocean University of China 2018年第3期17卷 697-704页

作者： MU Weijie warren alan PAN Xuming YING Chen College of Life Science and Technology Harbin Normal University Department of Life Sciences Natural History MuseumLondon

Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC_(50)(i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L^(-1) for chlorpyrifos and 0.0685 mg L^(-1) for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075–0.0093 mg L^(-1) for chlorpyrifos and 0.2640–0.2750 mg L^(-1) for dimethoate. These results show that the fission time effective concentration is lower than the LC_(50) value in ciliates, indicating that fission time effective concentration is more suitable than the LC_(50) value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles.

关键词： ciliate fission time effective concentration LC50 pesticide ultrastructure

Colonization features of marine biofilm-dwelling protozoa in Chinese coastal waters of the Yellow Sea

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Marine Life Science & Technology 2020年第3期2卷 292-301页

作者： Mohammad Nurul Azim Sikder Henglong Xu alan warren Laboratory of Microbial Ecology Ocean University of ChinaQingdao 266003China Institute of Marine Sciences University of ChittagongChittagong 4331Bangladesh Department of Life Sciences Natural History MuseumLondon SW75BDUK

Colonization features of biofilm-dwelling protozoa,especially ciliates,are routinely used as a useful tool for marine *** this review,we summarize some of these features to develop an optimal sampling strategy for using biofilmdwelling protozoa as bioindicators of marine water *** focus on the utility of:(1)diversity in dices to analyze the colonizahon features of biofilm-dwelling protozoa for monitoring marine water quality;(2)MacArthur-Wilson and logistic equation models to determine spatio-temporal variations in colonization dynamics;and(3)homogeneity in taxonomic breadth of biofilm-dwelling protozoa during the process of *** main findings are that:(1)the colonization dynamics of biofilm-dwelling protozoa are similar at depths of 1-5 m in spring and autumn;(2)temporal variability was well fitted to the MacArthur-Wilson and logistic models(P<0.05);and(3)species composition reached an equilibrium after a colonization period of 10-14 days in spring and autumn,but this took less time in the summer and more time in the ***-plotting tests demonstrated spatial variability in homogeneity in taxonomic structure of the ciiiate communities at different depths in the water column,with high levels at 1 m and 2 m and lower levels at 3.5 m and 5 ***,the findings of this review suggest that the colonization dynamics of biofilin-dwelling protozoa may be influenced by different depths and seasons in coastal waters and 1-2 m in spring and autumn may be optimal sampling strategy for bioassessment on large spatial/temporal scales in marine ecosystems.

关键词： Bioassessment Colonization survey Marine ecosystem Periphytic ciliates Taxonomic breadth Seasonal and vertical variations

From oral structure to molecular evidence:new insights into the evolutionary phylogeny of the ciliate order Sessilida(Protista,Ciliophora),with the establishment of two new families and new contributions to the poorly studied family Vaginicolidae

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Science China(Life Sciences) 2023年第7期66卷 1535-1553页

作者： Borong Lu Xiaozhong Hu alan warren Weibo Song Ying Yan Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao266003China College of Fisheries Ocean University of ChinaQingdao266003China Department of Life Sciences Natural History MuseumLondonSW75BDUK Laoshan Laboratory Qingdao266237China

Ciliated protists represent one of the most primitive and diverse lineages of eukaryotes,with nuclear dimorphism,a distinctive sexual process(conjugation),and extensive genome *** divergent ciliate lineages,the peritrich order Sessilida includes members with a colonial lifestyle,which may hint to an independent evolutionary attempt for multicellularity,although they are still single-celled *** date,the evolution and phylogeny of this group are still far from clear,in part due to the paucity of molecular and/or morphological data for many *** this study,we extend taxon sampling of a loricate group of sessilids by obtaining 69 new r DNA(SSU r DNA,ITS1-5.8S rDNA-ITS2,and LSU r DNA)sequences from 20 wellcharacterized representative species and analyze the phylogenetic relationships within *** main findings are:(i)the genera Rhabdostyla and Campanella each represents a unique taxon at family level,supporting the establishment of two new families,i.e.,Rhabdostylidae *** Campanellidae ***.,respectively,the former being sister to a morphologically heterogeneous clade comprising Astylozoidae and several incertae sedis species and the latter occupying the basal position within the Sessilida clade;(ii)the structure of infundibular polykinety 3 is likely to be a phylogenetically informative character for resolving evolutionary relationships among sessilids;(iii)differences between sparsely and the densely arranged silverline systems could be a suprageneric taxonomic character;(iv)the monophyly of Vaginicolidae is confirmed,which is consistent with its specialized morphology,i.e.,the possession of a typical peritrich lorica which might be an apomorphy for this group;(v)within Vaginicolidae,the monotypic Cothurniopsis sensu Stokes,1893 is a synonym of Cothurnia Ehrenberg,1831,and a new combination is created,i.e.,Cothurnia valvata ***.;(vi)Vaginicola sensu lato comprises at least two distinctly divergent clades,one affiliated w

关键词： evolutionary hypotheses new families peritrich ciliates phylogeny protist

Taxonomy and systematics of a new pleurostomatid ciliate, Pseudolitonotus spirelis gen. et sp. n. (Protozoa, Ciliophora, Haptoria)

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Marine Life Science & Technology 2022年第1期4卷 31-41页

作者： Lei Wu Jiqiu Li alan warren Xiaofeng Lin Laboratory of Protozoology Guangzhou Key Laboratory of Subtropical Biodiversity and BiomonitoringSchool of Life SciencesSouth China Normal UniversityGuangzhou510631China Key Laboratory of the Coastal and Wetland Ecosystems The Fujian Provincial Key Laboratory for Coastal Ecology and Environmental StudiesCollege of the Environment and EcologyXiamen UniversityXiamen361005China Department of Life Sciences Natural History MuseumCromwell RoadLondonSW75BDUK

Recent studies have revealed a high diversity of pleurostomatid ciliates in brackish habitats. Here, a novel species, Pseudolitonotus spirelis gen. et sp. n., isolated from a mangrove wetland of southern China, was investigated based on living observation, protargol staining, and molecular analyses. The new genus Pseudolitonotus gen. n. is characterized by the last left somatic kinety (LKn) being shortened and none of the right somatic kineties extending to the anterior end of the cell, thus distinguishing it from all known pleurostomatid genera. The type species, Pseudolitonotus spirelis sp. n., is characterized by the possession of two macronuclear nodules, 11–15 right and 7–9 left kineties, a single contractile vacuole subterminally located, extrusomes evenly spaced along the entire ventral margin and some forming an “apical group”, two types of cortical granules, and the bottom of the oral slit invariably being twisted. Litonotus gracilis (Pan et al. Eur J Protistol 51:494–506, 2015) is believed to be another member of this new genus as its LKn and right somatic kineties are all shortened. Hence, a new combination, Pseudolitonotus gracilis (Pan et al., 2015) comb. n., is suggested and its diagnosis is improved. Molecular phylogenetic analyses based on SSU rDNA sequence data reveal that Pseudolitonotus gen. n. is monophyletic and groups with Apolitonotus (Pan et al. J Eukaryot Microbiol 67:252–262, 2020) of the family Protolitonotidae (Wu et al. Zool Scr 46:245–253, 2017). However, the familial assignment of this new genus is uncertain based on current data.

关键词： Biodiversity Litonotus gracilis Molecular phylogeny New combination New genus New species

Morphogenesis of the Euplotid Ciliate Uronychia binucleata Young, 1922(Ciliophora, Hypotrichia)

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Journal of Ocean University of China 2019年第2期18卷 467-473页

作者： MA Honggang LI Jingbao warren alan BA Sang LU Xiaoteng The Key Laboratory of Mariculture Ministry of Education Ocean University of China Key Laboratory for Space Bioscience and Biotechnology Institute of Special Environmental Biophysics School of Life Sciences Northwestern Polytechnical University Department of Life Sciences Natural History MuseumLondon School of Sciences Tibet University Research Department for Limnology University of Innsbruck

Morphogenesis of a population of the marine euplotid ciliate, Uronychia binucleata, which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier, Qingdao, China, was investigated using protargol staining. The main pattern of morphogenesis is typical for the genus and can be summarized as follows: 1) the oral primordium in both proter and opisthe develops de novo in a subcortical pouch. In each daughter cell, the developing adoral zone of membranelles divides into two parts. The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones; six parental membranelles are retained by the proter; 2) the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch; 3) five primary front oventral-transverse cirral anlagen appear de novo on the cell surface; 4) the marginal cirral anlagen are formed de novo; 5) the leftmost frontal cirrus develops de novo on the cell surface; 6) two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus. In contrast to its congeners, the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter.

关键词： Euplotida hypotrichs ontogenesis Uronychia

Comparative Evaluation on Combined Ecotoxic Effects of Nitrofurazone and NH_(4)Cl Using Two Ciliated Protists as Model Organisms:Population Dynamics and Growth Rates

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Journal of Ocean University of China 2021年第1期20卷 137-146页

作者： YU Ziyue LIU Shuxing CHEN Xin warren alan LIN Xiaofeng LI Jiqiu Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring South China Normal UniversityGuangzhou 510631China Department of Life Sciences Natural History MuseumCromwell RoadLondon SW75BDUK The Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies College of the Environment and EcologyXiamen UniversityXiamen 361005China Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem College of the Environment and EcologyXiamen UniversityXiamen 361005China

Ecotoxic effects of antibiotics or ammonium have been confirmed independently in aquatic animals,but few studies have investigated their combined *** aquaculture ecosystems,these pollutants frequently coexist,and often in high *** this study,the combined effects of antibiotic nitrofurazone and NH4 Cl on the population dynamics and growth rates of two species of ciliated protists,Euplotes vannus and Pseudokeronopsis rubra,were *** of the dose-responses were visualized,and interactions between the two pollutants were quantified by the response surface method(RSM).Results showed that 1)the dynamics of the population growth differed significantly between the testd ciliates and varied with the concentrations of the pollutants;2)the relative growth rate(RGR)of both ciliates decreased significantly with increased pollutant concentrations,while the difference in RGR between the two ciliates was not significant;3)RSM analysis demonstrated an additive effect of nitrofurazone and NH4 Cl on the RGR in both *** brief,ecotoxic effects can be caused by nitrofurazone and ammonium independently on the two test ciliates,and such effects can be strengthened when they present at the same *** findings offer a valuable reference for evaluating combined ecotoxic effects caused by multiple pollutants in aquaculture ecosystems.

关键词： ciliates combined ecotoxicity nitrofurazone NH4Cl population growth