MORPHOLOGICAL STUDIES OF LYMNAEID SNAILS FROM THE HUMAN FASCIOLIASIS ENDEMIC ZONE OF BOLIVIA

The taxonomic position of the Lymnaeidae from the BolivianAltiplano has been unclear. On the basis of conchological characters,some authors reported two species from this area, Lymnaea viatrix andL. cubensis while others, considering also anatomical characters,considered L. viatrix as a synonym of L. cubensis. More recentstudies demonstrated genetic identity between the Bolivian lymnaeidsand L. truncatula from the Iberian Peninsula. Populations recognizedas L. cubensis correspond to a distinct genetic group, but geneticinformation was not available for L. viatrix. In the light ofthese genetic results, a morphometric study of both the shell (usingRaupian parameters) and male reproductive system was carried outof L. cubensis from Cuba (type locality), Dominican Republic,Guadeloupe and Venezuela, and of L. truncatula from Bolivia,France, Portugal, Spain and Morocco. Syntypes of L. viatrixfrom Argentina (var. A. ventricosa) and specimens of L. viatrix(var. B. elongata) from the type locality, Peru, were also studied(conchological characters only). The conchological study showedthe presence of a large amount of variability between populations.This variability was not congruent with genetic results. Alarge amount of variability was also found using anatomicalcharacters of the male reproductive system and all of them clearlyseparate L. cubensis from L. truncatula independently from geographicalorigin. Thus anatomical characters, unlike conchological parameters,do differentiate taxonomic species inferred from genetic studies. (Received 11 September 1997; accepted 5 March 1999)     

Fascioliasis of livestock and snail host for Fasciola in the Altiplano Region of Bolivia.

Fascioliasis caused by Fasciola hepatica was a serious problem for sheep and alpacas in the Altiplano Region of Bolivia. In some provinces close to Lake Titicaca, the raising of sheep was forced to discontinue, because infection with the fluke made it unprofitable and almost impossible. It was proved that in the Altiplano Region, two species of freshwater snails, Lymnaea viatrix and L. cubensis var., served as intermediate hosts for F. hepatica. In some subtropical areas of Bolivia, these snails could not be found, although other Lymnaea sp. was widely distributed there. As it is possible for Lymnaea sp. to be intermediate host for the fluke, further studies are required on the identification. Acute fascioliasis of sheep occurred in the Altiplano Region principally during a period from May to July, or the dry season. In some areas, the mortality rate of infected sheep was roughly estimated as 15 to 25% annually. Contamination with Fasciola metacercariae of herbage and semi-aquatic plants grown in a swamp in one of these areas was biologically assessed, using guinea pigs. Plants of Compositae and Eleocharis sp. were contaminated most intensely and those of Senicio sp. and Vallisneria sp. carried a fairly large number of cysts, while plants of Scirpus sp. and Ranunclaceae carried only a few cysts. No signs of Fasciola infection were observed in any animal given the plants of Liliaceae.     

The use of the polymerase chain reaction and restriction fragment length polymorphism technique associated with the classical morphology for characterization of Lymnaea columella, L. viatrix, and L. diaphana (Mollusca: Lymnaeidae)

The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results.     

Southernmost finding of Lymnaea viatrix orbigny, 1835 (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica (Linnaeus, 1758) (Trematoda: Digenea), in urban and rural areas of Patagonia, Argentina

We report the first finding of Lymnaea viatrix south of parallel 41 masculine S, in rural and urban areas from Argentina. Ninety snails were collected during year 2000, from a concrete pond at a Public Square in El Bolsón Village, Río Negro province, and 811 snails in November 1999, and during 2000 from waterbodies within a farm at Cholila locality, Chubut province. Fasciola hepatica infection was detected in 0.9% snails from the rural area. We discuss the potential risk of L. viatrix to public health in urban areas and its epidemiological importance in rural areas of the Andean Patagonian region.     

湖南植物志资料（一）木兰科、八角科、五味子科、樟科、水马齿科补遗

本文报道了湖南植物新记录共计１１种,隶属于５科１０属．归并樟科植物３种２变种：将石木姜子ＬｉｔｓｅａｆａｂｅｒｉＨｅｍｓｌ．和近轮叶木姜子Ｌ．ｓｕｂｖｅｒｔｉｃｉｌｌａｔａＹａｎｇ归入黄丹木姜子Ｌ．ｅｌｏｎｇａｔａ（Ｗａｌｌ．ｅｘＮｅｅｓ）Ｂｅｎｔｈ．ｅｔＨｏｏｋ．ｆ．,将长梗绒楠ＭａｃｈｉｌｕｓｖｅｌｕｔｉｎａＣｈａｍｐ．ｅｘＢｅｎｔｈ．ｖａｒ．ｌｉｎｇｉｐｅｄｕｎｃｕｌａｔａＣ．Ｊ．Ｑｉ归入绒毛润楠Ｍ．ｖｅｌｕｔｉｎａＣｈａｍｐ．ｅｘＢｅｎｔｈ．,将短梗新木姜子ＮｅｏｌｉｔｓｅａｂｒｅｖｉｐｅｓＨ．Ｗ．Ｌｉ归入美丽新木姜子Ｎ．ｐｕｌｃｈｅｌｌａ（Ｍｅｉｓｓｎ）Ｍｅｒｒ．,将紫云山新木姜子Ｎ．ｗｕｓｈａｎｉｃａ（Ｃｈｕｎ）Ｍｅｒｒ．ｖａｒ．ｐｕｂｅｎｓＹａｎｇｅｔＰ．Ｈ．Ｈｕａｎｇ归入巫山新木姜子Ｎ．ｗｕｓｈａｎｉｃａ（Ｃｈｕｎ）Ｍｅｒｒ．．     

泡桐叶片蛋白质多态性及其聚类分析

研究了9种泡桐叶片蛋白质的多态性,并根据其叶片蛋白质聚丙烯酰胺凝胶单向和双向电泳结果,将它们聚类为白花泡桐组[白花泡桐（Paulownia fortunei）和白花兰泡桐（P.elongata f.allba）]、南方泡桐组[南方泡桐（P.australis )和成都泡桐（P.albiphloea var.chengtuensis)]和毛泡桐组（毛泡桐（P.tomentosa）、川泡桐（P.fargesii）、鄂川泡桐（P.albiphloea）、山明泡桐（P.lamprophylla）和兰考泡桐（P.elon-gata）]。该结果可为了解泡桐属植物的亲缘关系和种的鉴定提供参考依据。     

Rediae of echinostomatid and heterophyid trematodes suppress phagocytosis of haemocytes in Littorina littorea (Gastropoda: Prosobranchia)

A modulation of the phagocytic activity of hemocytes from the common periwinkle Littorina littorea by secretory-excretory products (SEP) released by trematode rediae during axenic in vitro cultivation was studied. The SEP released by the parasites Himasthla elongata (Echinostomatidae) and Cryptocotyle lingua (Heterophyidae) were found to inhibit the phagocytosis of zymozan particles by periwinkle hemocytes. The specificity of SEP effects was assessed: SEP of Himasthla militaris and Cryptocotyle concavum, two trematodes belonging to the same genera but infecting another closely related prosobranch snail Hydrobia ulvae, were also shown to be able to suppress L. littorea hemocytes phagocytic activity. However, no decrease in phagocytosis rate was observed when SEP of H. elongata and C. lingua were applied to monolayers of hemocytes from the bivalve mollusc Mytilus edulis. SEP from H. elongata was fractionated; only those fractions containing proteins of molecular weight more than 50 kDa were shown to possess inhibitory activity. Different H. elongata SEP concentrations were tested in for their ability to suppress phagocytosis by L. littorea hemocytes. Even very low SEP concentrations were shown to retain their ability to decrease phagocytosis rate, the inhibitory effect being dose-dependent. Hemocytes derived from snails naturally infected with H. elongata were also found to have lower phagocytic ability as compared to healthy individuals.     

Control of downy mildew (Pseudoperonospora cubensis) of greenhouse grown cucumbers with alternative biological agents

In organic cucumber production infection with downy mildew (Pseudoperonospora cubensis) is a major problem. Plant extracts from Glycyrrhiza glabra L. (licorice), a plant belonging to the family Fabaceae, and Salvia officinalis (sage) as well as cultures of the bacterium Aneurinibacillus migulanus were investigated for efficacy of disease control under commercial growing conditions. Contrary to bioassays, where sage extract and the microorganism showed highest activity, in the trials of 2008 G. glabra extract was more effective than sage extract or A. migulanus against P. cubensis. Parameters such as concentrations of the preparations or application intervals could have been the reason for this. In the following year's trial (2009) the concentration of these agents was therefore increased somewhat and plants were either treated in seven day application intervals or in ten day application intervals. In the semi-commercial trials of 2009 all alternative biological agents showed good efficacies up to around 80% against infection with downy mildew. The application interval seemed to have a marginal effect only. Again, the licorice extract tended to be the best agent.     

我国特有植物一木里香橼叶精油化学成分的研究

用气相色谱保留指数定性法、色谱-质谱-计算机联用测定和标准品迭加法分析了木里香橼叶精油的化学成分。从分离出的59个色谱峰中鉴定了31个化合物。其中主要成分是柠檬烯(31.730％)、芳樟醇(1.554％)、香茅醛(23.383％)、香茅醇(1.189％)、橙花醇(11.777％)、香叶醛(16.544％),乙酸香茅酯(1.427％)、乙酸橙花酯(2.258％)、乙酸香叶酯(4.714％)等。把木里香橼叶油与木里香橼果皮油与云南野香橼叶油分别作了比较。结果表明木里香橼叶油中含氧化合物醇、醛、酯的含量相当高,是精油的主要成分,可能作为进口橙叶油的较好的代用品,是一种很有潜力的天然香料资源。     

N. elongata produces type IV pili that mediate interspecies gene transfer with N. gonorrhoeae

The genus Neisseria contains at least eight commensal and two pathogenic species. According to the Neisseria phylogenetic tree, commensals are basal to the pathogens. N. elongata, which is at the opposite end of the tree from N. gonorrhoeae, has been observed to be fimbriated, and these fimbriae are correlated with genetic competence in this organism. We tested the hypothesis that the fimbriae of N. elongata are Type IV pili (Tfp), and that Tfp functions in genetic competence. We provide evidence that the N. elongata fimbriae are indeed Tfp. Tfp, as well as the DNA Uptake Sequence (DUS), greatly enhance N. elongata DNA transformation. Tfp allows N. elongata to make intimate contact with N. gonorrhoeae and to mediate the transfer of antibiotic resistance markers between these two species. We conclude that Tfp functional for genetic competence is a trait of a commensal member of the Neisseria genus. Our findings provide a mechanism for the horizontal gene transfer that has been observed among Neisseria species.     

三种菜豆凝集素的分离纯化及其与黑皮扁豆凝集素抗血清的免疫交叉反应

利用Tris-HCl缓冲液浸提、硫酸铵分级沉淀、离子交换和分子筛层析,分别从白花菜豆(Phaseolus albiflora L.var)、紫花菜豆(Phaseolus purpurea L.var)、红花菜豆(Phaseolus coccineus L.var)种子中纯化得到3种菜豆凝集素(PAL,白花菜豆凝集素;PPL,紫花菜豆凝集素;PCL,红花菜豆凝集素).纯化的3种菜豆凝集素经SDS-PAGE电泳检测都只有一个分子量约为32 kD的亚基,它们都能与黑皮扁豆凝集素抗血清发生免疫交叉反应.     

两种纺织娘线粒体基因组的比较分析

目前关于螽斯科昆虫的线粒体基因组全序列及其分子进化的研究报道很少。本研究利用L-PCR技术结合嵌套步移PCR扩增获得纺织娘Mecopoda elongata和日本纺织娘M. niponensis的线粒体基因组全序列, 同时对二者之间的碱基组成和结构特点进行了比较分析。结果显示： 纺织娘线粒体基因组（GenBank登录号JQ917910）序列全长15 284 bp, A+T含量71.8%; 日本纺织娘线粒体基因组（GenBank登录号 JQ917909）序列全长15 364 bp, A+T含量72.4%; 2种纺织娘序列长度差异主要是控制区长度不同引起（纺织娘控制区长294 bp, 日本纺织娘控制区长393 bp）。2种纺织娘基因组基因含量、 相对位置及转录方向均与其他已报道的螽斯科昆虫一致, 未发现基因重排现象; 基因组中均存在较长的间隔序列, 在trnA/trnR之间的间隔序列长度分别为63 bp与68 bp, 在trnQ/trnM之间的分别为55 bp和26 bp, 在trnS^UCN/nad1之间的均为21 bp。而最长的基因重叠区域在2种纺织娘trnC/trnW之间均为8 bp, 在atp8/atp6和nad4L/nad4L之间均为7 bp。蛋白质编码基因的碱基组成和密码子使用均具有明显的偏倚性; 除nad1和nad2以特殊的TTG作为起始密码子, cox1使用特殊的起始密码子ATGA外, 其余的10种蛋白质编码基因均使用典型的ATN作为起始密码子。在tRNA基因中, 除trnS^AGN外, 均能折叠形成典型的三叶草形二级结构。在这些tRNA基因中均存在一定数目的以G-U错配为主的碱基错配, 类似现象同样存在于其他已测定的六足动物线粒体基因组中, 表明G-U配对在线粒体基因组中很可能是一种完全正常的碱基配对方式。基因组中控制区的A+T含量略低于线粒体基因组的其他区域, 表明高A+T含量并不是该区域的必要特征。本研究结果为螽斯科系统发生关系重建积累了有价值的数据资料。     

Structure of Aegilops ventricosa chromosome 6Nv, the donor of wheat genes Yr17, Lr37, Sr38, and Cre5.

An Aegilops ventricosa Tausch (2n = 28, DvDvNvNv) subtelocentric chromosome added to wheat (Triticum aestivum L.) in a disomic addition line was found to carry the genes for resistance Yr17, Lr37, Sr38, and Cre5 already transferred onto chromosome 2AS of the wheat line VPM1. Previous works demonstrated that this Ae. ventricosa chromosome is translocated with respect to the standard wheat genome. The present investigations showed that this chromosome pre-existed in Ae. ventricosa and contains only chromatin specific to the N genome. Using biochemical markers and suitable cytogenetic materials including the monoisosomic addition line for the translocated long arm (6NvL-2NvS), its structure was defined as being 6NvSdel.6NvL-2NvS. It consists of a segment of the short arm 2Nv, containing the resistance genes, attached to a group 6 chromosome lacking a distal part of its short arm. The 2 re arrangements could already be present in Aegilops uniaristata Vis. (2n = 14, NN), the source of the Nv genome of Ae. ventricosa.     

粘类非1BL/1RS小麦CMS基因定向选择及其育性特性的研究

对携有不同不育基因的4个粘类小麦雄性不育系进行了定向选择与鉴定,并对其育性特性进行研究,以选育更具应用价值的粘类非1BL/1RS小麦雄性不育系,推动三系杂交小麦的实际应用.结果表明:(1)根尖体细胞随体鉴定和A-PAGE技术分析筛选出的SP4、莫迦小麦为非1BL/1RS类型,其它供试不育系均属于1BL/1RS类型;(2)减数分裂及成熟花粉粒形态观察,粘类非1BL/1RS小麦雄性不育系其不育性是在整个配子发育过程中连续产生的,且在B型不育细胞质背景下,SP4和莫迦小麦的花粉细胞学形态与在K、Ven型2种不育细胞质背景下的不同,B型不育细胞质背景下SP4和莫迦不育系的花粉萌发率比K、Ven型不育细胞质背景下的花粉萌发率高;(3)以不同来源不育基因培育成的粘类K、Ven型非1BL/1RS不育系育性恢复性测定发现,SP4、莫迦小麦2种雄性不育系育性恢复性有一定差异,莫迦小麦不育类型育性恢复性高于SP4.     

Analysis of introgression of <Emphasis Type="Italic">Aegilops ventricosa</Emphasis> Tausch. genetic material in a common wheat background using C-banding

Seven Triticum aestivum (cv. Moisson)-Aegilops ventricosa addition lines and four VPM-1 lines were studied by C-banding, and compared with the parental common wheat cultivars Marne-Desprez (hereafter Marne), Moisson, and A. ventricosa lines 10 and 11. All of the VPM-1 lines had similar C-banding patterns and carried the same major 5B:7B translocation as the parental Marne cultivar. According to the C-banding analysis, the VPM-1 lines carry a complete 7D(7D(v)) chromosome substitution and a translocation involving the 5D and 5D(v) chromosomes. However, the translocation of the 2N(v)/6N(v) chromosome of A. ventricosa to the short arm of the 2A chromosome of wheat that had been identified in an earlier study using molecular analysis (Bonhomme A, Gale MD, Koebner RMD, Nicolas P, Jahier J, Bernard M in Theor Appl Genet 90:1042-1048, 1995; Jahier J, Abelard P, Tanguy AM, Dedryver F, Rivoal R, Khatkar S, Bariana HS Plant Breed 120:125-128, 2001) was not detected in our study. However, the appearance of a small pAs1 site at the tip of the chromosome 2A short arm in VPM-1 could be indicative of a minor translocation of the A. ventricosa chromosome. The 5B:7B translocation was also found in all seven T. aestivum-A. ventricosa addition lines, although it was not present in the parental common wheat cultivar Moisson. These lines showed different introgression patterns; besides the addition of the five N(v)-genome chromosomes, they also possessed different D(D(v)) genome substitutions or translocations. A whole arm translocation between chromosome 1N(v) and 3D(v) was identified in lines v86 and v137, and also in the A. ventricosa line 10. This observation lends further support to the idea that A. ventricosa line 10, rather than line 11, was used to develop a set of wheat A. ventricosa addition lines.     

中国产龙葵数值分类的研究

本文通过对龙葵及变种黄果龙葵和少花龙葵的形态特征比较及系统聚类分析研究,认为可分为２个种及１个变种。     

Planorbidae, lymnaeidae and physidae of Argentina (mollusca: basommatophora)

In the course of several trips to Argentina I had the opportunity of collecting specimens of Acrorbis petricola Odhner,1937, Biomphalaria orbignyi Paraense, 1975, B. peregrina (Orbigny, 1835), B. tenagophila (Orbigny, 1835) Lymnaea viatrix Orbigny, 1835, Antillorbis nordestensis (Lucena, 1954), B. intermedia (Paraense & Deslandes, 1962), B. oligoza Paraense, 1974, B. straminea (Dunker, 1848), Drepanotrema anatinum (Orbigny, 1835), D. cimex (Moricand, 1837), D. depressissimum (Moricand, 1837), D. heloicum (Orbigny, 1835), D. kermatoides (Orbigny, 1835), D. lucidum (Pfeiffer, 1839), L. columella Say, 1817, Physa acuta Draparnaud, 1805, and P. marmorata Guilding, 1828.