一种雷氏放射孢子虫的鉴定及其特征描述

放射孢子虫(Actinosporean)是黏体动物在其中间宿主水生无脊椎动物体内的一个生活阶段。研究鉴定并描述了一种雷氏放射孢子虫的形态和分子特征。该放射孢子虫的主要形态结构是: 由三个极囊、内含孢原质的孢子体和三个尾突组成, 无孢柄。极囊位于孢子体顶端, 呈梨形, 长5.2 μm, 宽2.9 μm; 孢子体侧面观呈长椭圆形, 长16.4 μm, 宽9.5 μm; 三个尾突基本等长, 呈锚状, 平均长度102.6 μm, 宽9.54 μm, 尾突末端轻微的上翘。每个尾突远侧端表面有许多形状不规则的棘状小刺。18S rDNA序列比对表明, 该雷氏放射孢子虫与国外已报道的Myxobolus cultus 18S rDNA序列一致性最高, 达98.41%, 由此推测该雷氏放射孢子虫可能为M. cultus的对应放射孢子虫阶段。研究丰富了国内放射孢子虫的基础研究。     

New subgenus of the genus Schizoprymnus (Hymenoptera: Braconidae) from Japan, having a unique abdominal carapace structure

A new subgenus of the genus Schizoprymnus Foerster is described and figured from Honshu, Japan. The subgenus, Ibarakius subgen. nov., comprises three species, S. (I.) gotoi sp. nov. (type species), S. (I.) kaizawus sp. nov., and S. (I.) honshuensis sp. nov. A pair of long, curved posteroventral processes on the carapace is unique to Ibarakius subgen. nov. The variability of frontal protuberances and sutures of the carapace in the brachistine genera Triaspis Haliday and Schizoprymnus Foerster is discussed.     

Hungactinomyxon,a new actinosporean type and collective group(Myxozoa) from <Emphasis Type="Italic">Branchiura sowerbyi</Emphasis> Beddard (Oligochaeta)

Actinosporeans are characterised by great morphological diversity. As it has been proved that the class Actinosporea is a synonym of the Myxosporea, actinosporean genera have only been regarded only as actinosporean collective groups. While most actinosporeans are released individually by their oligochaete hosts, members of the synactinomyxon, siedleckiella and antonactinomyxon collective groups are released as eight connected structural elements. These actinosporean types are differentiated by the type of unit and junction of the caudal processes. On the basis of these characteristics, a new actinosporean type, constructed from eight echinactinomyxon units, is described as hungactinomyxon. Adjacent units are joined by two of their three processes and form two interconnected cubes, each containing four echinactinomyxons. Molecular biological studies also suggest that this new actinosporean type differs from other actinosporean types built up from eight structural elements for which 18S rDNA sequences are available in GenBank.     

Phenotypes of dendritic cells in central lymph of healthy rabbits and during correction of experimental atherosclerosis]

Dendritic cells of central lymph of rabbits have been identified according to the form of the cell body, characteristics of formation and branchiness of its processes in health, in atherosclerosis, its correction with radon, polyphenol preparations made of Sanguisorba officinalis and in combination of the latter. Two main types of dendritic cells have been distinguished. Type I is characterized by a rounded body with clear outlines, protrusions and one compact process. Such cells are often found in lymph of intact animals. Type II has a cell body of various forms with two and more compact or branching processes. This type is mainly detected in atherosclerosis and its correction. The prevalence of the above phenotypes of dendritic cells is attributed to the response of the immune system to atherosclerosis and its correction.     

Physical mapping of rDNA sequences in four karyotypes of Ranunculus silerifolius (Ranunculaceae)

The chromosomal locations of the 18S-5.8S-26S rDNA and 5S rDNA sequences were examined in four cytotypes of Ranunculus silerifolius (the Matsuyama, Mugi, Otaru, and Karatsu types) using fluorescence in situ hybridization (FISH). Using the 18S-5.8S-26S rDNA probe, one pair of probe hybridization sites was detected by FISH in the interstitial region corresponding to the secondary constriction on the short arm of a satellite chromosome (chromosome pair 6) in all four karyotypes. FISH using 5S rDNA identified one pair of sites. The 5S rDNA locus was on different chromosomes in the four karyotypes: in the interstitial region of the short arm of the largest metacentric chromosome (chromosome pair 1) in the Matsuyama type, in the interstitial region of the short arm of the subtelocentric chromosome (pair 2) in the Mugi and Otaru types, and in the interstitial region of the short arm of the metacentric chromosome (pair 2) in the Karatsu type. This physical mapping of the 5S rDNA provides valuable information about karyotype evolution in R. silerifolius. Possible mechanisms of chromosome evolution are discussed.     

Video-microscopy observations of fast dynamic processes in the protozoon Giardia lamblia

Video-microscopy in combination with digital image processing was used to analyze dynamic processes associated to the life cycle of Giardia lamblia trophozoites. These parasites swim and attach to the epithelial cells, producing the disease known as Giardiasis. Giardia is a multiflagellar cell, presenting 4 pairs of flagella. With the use of analogue and digital tools, we observed that in cells attached to glass slides only 2 of the 4 pairs present active beating (wave propagation). The frequency observed was 17-18 Hz to the anterior and 8-11 Hz to the ventral flagella. These data resulted from several hours of recording using both analogue video and high-speed digital camera. The caudal pair did not show active beating patterns and the same holds true for the posterior one. In this latter pair, oscillations were observed, but they were always associated to the transit of the wave produced by the ventral pair. The analysis performed with free moving cells showed that during its forward dislocation, Giardia lamblia presented either a lateral rocking or a complete rotational (tumbling) movement around its longitudinal axis. A dislocation of the caudal region of the cell both in the lateral and dorso-ventral direction was observed. This movement was completely independent from the flagellar beating and it is likely to be produced by a microtubular complex located in the caudal portion of the cell. The adhesion process of Giardia lamblia was also followed by video-microscopy and the data showed that the ventral disk had an active participation in this process.     

Review of naupliar development among Miraciidae (Copepoda,Harpacticoida) with a naupliar description of <Emphasis Type="Italic">Paramphiascella</Emphasis><Emphasis Type="Italic">choi</Emphasis> sp. nov. from Thailand

Both genders of Paramphiascella choi sp. nov. were collected from the green alga Enteromorpha clathrata in Rayong province, Thailand. P. choi shares with other species of the genus: cylindrical body shape, rostrum not bifid, eight-segmented antennules, three-segmented exopodal antenna, and female P5 exopod with five setae. The new species distinguished from other conspecific species by: three-segmented exopodal antenna, inner edge of basis of male P1 and P2 bear a bare ovate-knob each. Enp-1 very elongate, Enp-2 of male P2 transformed into a large, strong, slightly curved and tapering attenuation with two central chitinous ridges, and bearing one medially directed knob close to enp-1. At the base of this knob arise three plumose setae of unequal length. These characters are suggested to be autapomorphies of the new species. Six naupliar stages are obtained and described a key for the identification of stages is provided. Nauplius I has one pair of caudal setae; three-segmented antennules; antenna consists of a coxa, basis, endopod and exopod; mandible has a coxa, basis, endopod and exopod; hindbody bears two caudal setae. Nauplius II develops one aesthetasc on the antennule; antenna has added an arthrite arising from the coxa; mandible has a row of tiny spinulose setae. Nauplius III has added two pairs of caudal setae. Nauplius IV bears bilobed bud of the maxillule armed with two setae and four pairs of caudal setae. Nauplius V bears a multilobed bud of the maxillule with three setae and five pairs of caudal setae. At Nauplius VI, the buds of swimming legs 1 and 2 are added.     

Two new species of Sarcocystis (Apicomplexa: Sarcocystidae) infecting the wolverine (Gulo gulo) from Nunavut, Canada

Infection with Sarcocystis species is common in many species of animals, but it has not yet been reported in wolverines (Gulo gulo). Histological sections of tongues from 41 wolverines in the Kitikmeot Region, Nunavut, Canada, were examined for sarcocysts. Sarcocysts were found in 33 (80.4%) wolverines. Two structurally distinct types of sarcocysts were found. Type A sarcocysts were thin (<1 μm thick) walled. Ultrastructurally, the parasitophorous vacuolar membrane (Pvm) had minute undulations, but it lacked villar protrusions and was not invaginated into the granular layer. The bradyzoites were slender, about 5 × 1 μm in size. Structurally, these sarcocysts were distinct from known species of Sarcocystis and possessed a novel 18S and ITS-1 sequence, sharing 98% and 78% sequence similarity with Sarcocystis canis . A new species name, Sarcocystis kalvikus, is proposed for type A sarcocysts. In contrast, type B sarcocysts had relatively thicker (about 2 μm) cyst walls and larger bradyzoites, each about 10 × 2-3 μm. Ultrastructurally, the Pvm on the sarcocyst wall had villar protrusions that were either mushroom-like or sloping. Molecular analysis identified a unique 18S and ITS-1 sequence that placed them in a clade within the Sarcocystidae. Based on histology, TEM, and genetic data, the new name, Sarcocystis kitikmeotensis, is proposed. Sarcocystis kalvikus was found in 14 (34.1%), S. kitikmeotensis was found in 7 (17%), and both species were found in 12 (29.2%) of 41 wolverines.     

Two-dimensional electron microscopic analysis of the chalice form of phosphorylase kinase

Phosphorylase kinase (Mr 1.3 X 10(6], a Ca2+-calmodulin-dependent protein kinase, plays a key role in the initiation of glycogenolysis. After purification on hydroxylapatite, the negatively stained enzyme was used for electron microscopy. In electron micrographs, phosphorylase kinase shows two major molecular forms: a butterfly form (approx. 60%) and a chalice form (approx. 40%). Images of the chalice form of the enzyme were computer-averaged by the method of single particle averaging. The following apparent molecular dimensions were obtained from the averages: total height, 20 nm; maximal width, 18 nm. The chalice form of phosphorylase kinase consists of a major structure termed the cup (11 nm X 18 nm), containing a large accessible cleft, and a minor structure termed the stem (8 nm X 9 nm). A closer examination of the images by averaging of molecular parts revealed two subpopulations of the cup part: a flexed (closed) type and an extended (open) type. The orifice, which can be closed partly by two protrusions (I, I'), is about 6 nm wide when the protrusions are flexed and 9 nm wide when they are extended. It is suggested that the substrates, e.g. phosphorylase b, may be accommodated in the large cleft of the enzyme. While the orientation of the protrusions (I, I') is the most obvious difference between the two types, more structural differences can be detected, suggesting a concerted movement of the protein domains against each other.     

Ciliates from Antarctic sea ice

Five ciliates, Chlamydonella prostomata nov. sp., Paractedoctema acruosa nov. gen., nov. sp., Urocyclon ovatum nov. gen., nov. sp., Porpostoma grassei (Corliss and Snyder 1986) and Cytharoides balechi Tuffrau 1974, collected from sea ice in the Weddell Sea, Antarctica were morphologically and taxonomically investigated. The new genus Paractedoctema is characterized as: Cyclidiidae with naked snout-like apical end and three well-developed membranelles which are multi-rowed in structure and closely apposed one to another; paroral membrane extending anteriorly to about mid-level of M1; one caudal cilium; and silverline system Cyclidium-like. Since Urocyclon Small and Lynn 1985 is a nomen nudum because no type species has been fixed, we re-establish the genus and give a revised definition: uronematids mostly with inverted pear-shaped body and subequatorially positioned cytostome; apical plate dominant; membranelle 1 highly reduced; and paroral membrane extending anteriorly to about mid-level of membrane 2. Based on this new definition, a new combination is suggested: Homalogastra cymruensis (Pérez-Uz and Hope 1997) comb. nov. (formerly Urocyclon cymruensis Pérez-Uz and Hope 1997). For the well-known genus Chlamydonella, an improved diagnosis has been given according to our observations and the data obtained: Lynchellidae without plasmatic protrusions on ventral side; several to many somatic kineties making no noticeable naked gap between left and right areas; perioral kineties continuous or slightly fragmented with leftmost rows parallel to each other, which are arched transversely; and cytopharyngeal rods (nematodesmata) toothed. Macronucleus usually dimorphic. Regarding the related genus Lynchella Kahl 1933, we suggest that the original diagnosis by Kahl should be maintained. Thus, the genus diagnosis is re-provided: Lynchellidae with plasmatic protrusions on ventral side; several to many somatic kineties making no noticeable naked gap between left and right areas; perioral kineties continuous or fragmented with some rows parallel to each other; cytopharyngeal rods toothed; macronucleus generally dimorphic. In the light of the redefinition, a new combination has been made: Chlamydonella nordica (Jankowski 1968) comb. nov. (formerly Lynchella nordica Jankowski 1968). Accepted: 10 October 1999     

云南西双版纳蓟马三新种记述

本文记述在我国云南西双版纳发现的蓟马3新种,即蕉爪哇蓟马Javathrips musae;葛藤伪棍蓟马Pseudodendrothrips puerariae,两种均属蓟马科(Thripidae);中华斑管蓟马Stigmothrips chinensis,属管蓟马科(Phlaeothripidae)。     

A Study on the Genus Gynostemma Bl. (Cucurbitaceae) from China

The genus Gynostemma B1. consists of 13 species and 2 varieties in the whole world, among which 11 species and 2 varieties occur in China. They are distributed in S. Shaanxi and the southern part of the Yangtze River (including Taiwan province) in China and also in Korea, Japan, Sri Lanka, India and Malesia. Based on the characters and dehiscence of fruit, the genus Gynostemma B1. may be divided into two subgenera, i.e. Subgen. I. Gynostemma and Subgen. II. Trirostllum (Z. P. Wang et Q. Z. Xie) C. Y. Wu ct S. K. Chen, comb. nov. 1. Subgenus Gynostemma. The fruits are baccate, globose, 3-umbonate and incorni culate on the apical side, indehiscent when mature. The style apex in female flower is bifid. Type of subgenus: Gynostemma pentaphyllum (Thunb.) Mak. This subgenus contains 8 species and 2 varieties in the world, among which 6 species and 2 varieties occur in China, i.e.1.G. simplicifolium B1. (Yunnan, Hainan of Guangdong); 2. G. laxum (Wall.) Cogn. (S. Yunnan, Hainan of Guangdong and Guangxi); 3. G. burmanicum King ex Chakr. (Yunnan), 3a. G. burmanicum var. molle C. Y. Wu (Yunnan); 4. G. pentaphyllum (Thunb.) Mak. (S. Shaanxi and the soutern area of the Yangtze River of China), 4a. G. pentaphyllum (Thunb.) Mak. var. dasycarpum C. V. Wu (Yunnan); 5. G. pubescens (Gagnep.) C. Y. Wu, st. nov. (Yunnan); 6. G. longipes C. Y. Wu, sp. nov. (endemic to China: Yunnan, Sichuan, Guizhou, Shaanxi and Guangxi). 2. Subgenus Trirostellum (Z. P. Wang et Q. Z. Xie) C. Y. Wu et S. K. Chen, comb. nov.——Trirostellum Z. P. Wang et Q. Z. Xie in Acta Phytotaxonomia Sinica 19 (4): 483. 1981, syn. nov. The fruit are capsules, subcampanulate, 3-corniculate on the apical side, dehiscent when mature. The style apex in female flower is luniform and irregularly denticulate at margin, rarely bifid. Type of subgenus: Gynostemma cardiospermum Cogn. ex Oliv. This subgenus comprises 5 species, which are all endemic to China. 1. G. yixingense (Z. P. Wang et Q. Z. Xie) C. Y. Wu et S. K. Chen (Jiangsu and Zhejiang); 2. G. cardio spermum Cogn. ex Oliv. (Hubei, Shaanxi and Sichuan); 3. G. microspermum C. Y. Wu et S. K. Chen (S. Yunnan); 4. G. aggregatum C. Y. Wu et S. K. Chen (NW. Yunnan); 5. G.laxiflorum C. Y. Wu et S. K. Chen (Anhui).     

Investigations of the butylcholinesterase-containing cells of the adenohypophysis of the white-crowned sparrow,Zonotrichia leucophrys gambelii

Summary In the adenohypophysis of Zonotrichia leucophrys gambelii two types of cells with butylcholinesterase(BuChE) activity can be demonstrated histochemically. Type I occurs in the cephalic lobe of the pars distalis and in the pars tuberalis; it consists of oval and round cells. It is a distinctive cell type that is identical with the amphophilic cells described by Matsuo, Vitums, King and Farner (1969). Whereas castration or inhibition of thyroid gland activity causes only minor changes in these cells, blocking of adrenal cortex activity, or adrenalectomy, causes conspicuous hyperplasia and hypertrophy suggesting that these cells are involved in the production or release of ACTH. The second type, which occurs in both cephalic and caudal lobes, consists mostly of irregularly formed cells. Various observations indicate that it is a composite group, consisting, at least in part, of degenerating cells.These investigations were supported by grants from the National Institutes of Health (S ROI NB 06812) and the National Science Foundation (GB 5969) to Professor Farner.     

Targeted gene knockout of inner arm 1 in Tetrahymena thermophila

Cilia and flagella contain at least eight different types of dynein arms. It is not entirely clear how the different types of arms are organized along the axoneme. In addition, the role each different type of dynein plays in ciliary or flagellar motility is not known. To initiate studies of dynein organization and function in cilia, we have introduced a mutation into one dynein heavy chain gene (DYH6) in Tetrahymena themophila by targeted gene knockout. We have generated mutant cells that lack wild-type copies of the DYH6 gene. We have shown that the DYH6 gene encodes one heavy chain (HC2) of Tetrahymena 18S dynein and that 18S dynein occupies the I1 position in the ciliary axoneme. We have also shown that Tetrahymena I1 is required for normal motility, normal feeding and normal doubling rate.     

Identification of lactic acid bacteria from fermented tea leaves (miang) in Thailand and proposals of Lactobacillus thailandensis sp. nov., Lactobacillus camelliae sp. nov., and Pediococcus siamensis sp. nov

Eighteen rod-shaped homofermentatives, six heterofermentatives, and a coccal homofermentative lactic acid bacteria were isolated from fermented tea leaves (miang) produced in the northern part of Thailand. The isolates were placed in a monophyletic cluster consisting of Lactobacillus and Pediococcus species. They were divided into seven groups by phenotypic and chemotaxonomic characteristics, DNA-DNA similarity, and 16S rRNA gene sequences. Groups I to VI belonged to Lactobacillus and Group VII to Pediococcus. All of the strains tested produced DL-lactic acid but those in Group IV produced L-lactic acid. The strains tested in Groups I, II and V had meso-diaminopimelic acid in the cell wall. Six strains in Group I were identified as Lactobacillus pantheris; five strains in Group II as Lactobacillus pentosus; and four strains in Group V as Lactobacillus suebicus. Two strains in Group VI showed high DNA-DNA similarity for each other and MCH4-2 was closest to Lactobacillus fermentum CECT 562(T) with 99.5% of 16S rRNA gene sequence similarity. Five strains in Group III are proposed as Lactobacillus thailandensis sp. nov., and MCH5-2(T) (BCC 21235(T)=JCM 13996(T)=NRIC 0671(T)=PCU 272(T)) is the type strain which has 49 mol% G+C of DNA. Two strains in Group IV are proposed as Lactobacillus camelliae sp. nov., and the type strain is MCH3-1(T) (BCC 21233(T)=JCM 13995(T)=NRIC 0672(T)=PCU 273(T)) which has 51.9 mol% G+C of DNA. One strain in Group VII is proposed as Pediococcus siamensis sp. nov., and MCH3-2(T) (BCC 21234(T)=JCM 13997(T)=NRIC 0675(T)=PCU 274(T)) is the type strain which has 42 mol% G+C of DNA.     

ZUR MORPHOLOGIE DER HAUPTSPEICHELDRÜSE VON MYZUS PERSICAE

Zusammenfassung Die Hauptspeicheldrüse von Myzus persicae (Sulz.) erwies sich als ein differenziert aufgebautes Organ. An herauspräparierten ganzen Drüsen, die nach Feulgen gefärbt waren, wurden Größe und Form der einzelnen Zellkerne verglichen und auf diese Weise neun verschiedene Drüsenzellen unterschieden.

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Summary Principal salivary glands were separated under a stereo-microscope from adult wingless Myzus persicae which had been totally immersed in Feulgen stain. The nuclei were compared in size and shape and then assigned to different gland cells. In this way at least nine different cell types could be differentiated in the principal salivary gland. They have been labelled with letters A to I (see Fig. 1). In the main region there are four A-cells in two pairs, one pair of B-cells with larger nuclei, and the odd C-cell, which has a nucleus about double the size of those in B-cells. On the other side of each gland lobe are one pair of D-cells and one pair of F-cells. Nuclei of E-cells are very small compared with those of G-cells, which are extremely large and show a loose structure. The region of cover cells is composed of five cells (H) with irregularly shaped and weakly staining nuclei, and one odd cell (I) with a circular, intensely stained nucleus. In further studies the different cell types will be determined by specific histochemical reactions with a view to distinguishing different kinds of transmission of plant viruses by aphids.