Corythus enucleator (Cuv. ex L.)in der Provinz Posen

Ohne Zusammenfassung     

The ROSA26 LacZ-neo R insertion confers resistance to mammary tumors in Apc Min/+ mice

B6.129S7-Gtrosa26 (ROSA26) mice carry a LacZ-neo ^R insertion on Chromosome (Chr) 6, made by promoter trapping with AB1 129 ES cells. Female C57BL/6J Apc ^Min /+ (B6 Min/+) mice are very susceptible to the induction of mammary tumors after treatment with ethylnitrosourea (ENU). However, ENU-treated B6 mice carrying both Apc ^Min and ROSA26 are resistant to mammary tumor formation. Thus, ROSA26 mice carry a modifier of Min-induced mammary tumor susceptibility. We have previously mapped the modifier to a 4-cM interval of 129-derived DNA that also contains the ROSA26 insertion. Here we report additional evidence for the effect of the ROSA26 insertion on mammary tumor formation. To test the hypothesis that the resistance was due to a linked modifier locus, we utilized two approaches. We have derived and tested two lines of mice that are congenic for 129-derived DNA within the minimal modifier interval and show that they are as susceptible to mammary tumors as are B6 mice. Additionally, we analyzed a backcross population segregating for the insertion and show that mice carrying the insertion are more resistant to mammary tumor development than are mice not carrying the insertion. Thus, the resistance is not due to a 129-derived modifier allele, but must be due to the ROSA26 insertion. In addition, the effect of the ROSA26 insertion can be detected in a backcross population segregating for other mammary modifiers. Received: 29 December 2000 / Accepted: 4 April 2001     

Beobachtung einesLanius excubitor

Ohne Zusammenfassung     

Translational control of development inC. elegans

Translational control by the 3′untranslated regions (3′UTRs) of mRNAs contributes to important events throughout the development of C. elegans. In oocytes and early embryos, maternal mRNAs are controlled by 3′UTR elements to restrict translation of their protein products to specific blastomeres. Localized translation is probably critical for specifying blastomere identity. In both germline and somatic cells, mRNAs from sex determining genes are translationally repressed by 3′UTR controls. These controls balance the activities that specify male and female cell fates. During larval development, the temporal sequence of cell lineages requires 3′UTR-mediated regulation of heterochronic genes by a small non-protein coding RNA. We review what is known about these translational control mechanisms in C. elegans. This overview illustrates that translational control by 3′UTR elements is a powerful mechanism for regulating the expression of multiple gene products in diverse cell types during development of a multi-cellular animal.     

Ueber Formen des Rephuhns,Starna cinerea L.

Ohne Zusammenfassung     

Molecular Basis for the rhino (hr)Phenotype: A Nonsense Mutation in the MousehairlessGene

The hairless (hr) and rhino (hr^rh) mutations are autosomal recessive allelic mutations that map to mouse Chromosome 14. Both hairless and rhino mice have a number of skin and nail abnormalities and develop a striking form of total alopecia at approximately 3–4 weeks of age. The molecular basis of the hairless mouse phenotype was previously found to be the result of a murine leukemia proviral insertion in intron 6 of thehrgene that resulted in aberrant splicing. In this study, we report a 2-bp substitution in exon 4 of thehrgene in a second allele ofhr,rhino 8J (hr^rh-8J), leading to a nonsense mutation. These findings document the molecular basis of the rhino phenotype for the first time and suggest that rhino is a functional knock-out of thehrgene.     

Isolation and Characterization of a New Member of the HumanLy6Gene Family(LY6H)

TheLy6family of genes encodes glycosylphosphatidylinositol-anchored cell surface glycoproteins expressed on various types of cells. Intriguing patterns of expression ofLy6genes on specific subpopulations of lymphoid and myeloid cells suggest that Ly6 molecules may be involved in the development and homeostasis of hematopoietic cells. We have isolated a new member of the humanLy6gene family,LY6H,from a human fetal brain cDNA library. Fluorescencein situhybridization and radiation hybrid analyses assignedLY6Hto chromosome 8, where other members of theLy6gene family are also located. Northern analysis revealed thatLY6His highly expressed in particular subdivisions of human brain and also in MOLT-3 and -4 acute lymphoblastic leukemia cells. These data suggest that LY6H may play a role(s) in both the central nervous system and the immune system.     

贵州剑河寒武系甲劳组复州虫(Fuchouia)研究*

三叶虫Fuchouia长期被作为贵州寒武系甲劳组生物地层划分和对比的重要依据,但关于Fuchouia和Parafuchouia的系统分类位置一直存在争议。主要有以下三个观点: Parafuchouia是Fuchouia的亚属、Parafuchouia是Fuchouia的晚出异名以及Parafuchouia可提升为一个单独的属。本文根据在剑河八郎甲劳组采集的Fuchouia [过去被报道为Parafuchouia或Fuchouia (Parafuchouia)]标本和前人报道的Fuchouia、Parafuchouia标本, 基于线性测量的几何形态测量方法, 对Parafuchouia和Fuchouia的头部形态特征进行分析研究, 结果显示Parafuchouia是Fuchouia的晚出异名, 其区别于Fuchouia的特征可作为种间差异的判定依据。这样, 剑河甲劳组可能是目前全球Fuchouia的最低产出层位之一。尽管Fuchouia在中国、朝鲜、印度—喜马拉雅、澳大利亚、哈萨克斯坦等地广泛分布, 但已报道的产出层位多从鼓山阶Ptychagnostus atavus带至古丈阶Lejopyge laevigata带, 延限跨度较大, 很难用Fuchouia这一属级单位来进行生物地层对比。因此贵州寒武系甲劳组目前已建立的Fuchouia生物地层带还需进一步商榷, 需具体到种一级别或另选其他对比分子才能与寒武系华南斜坡相区或华北台地相区进行更好的同期地层对比。     

大瑶山甜茶正丁醇部位化学成分研究

目的:研究大瑶山甜茶正丁醇部位中的二萜类化学成分,为探索其活性物质奠定基础。方法:采用95%乙醇提取药材,提取液回收至无醇味后溶于水中,依次用石油醚、乙酸乙酯和正丁醇萃取,减压干燥后获得相应萃取物,综合运用各种色谱技术对正丁醇萃取物进行分离纯化,获取二萜类化合物,通过NMR对得到的化合物进行结构鉴定。结果:从大瑶山甜茶中分离得到10个二萜类化合物,分别鉴定为7β, 17-dihydroxy-16β-ent-kauran-19-oic acid 19-O-β-D-glucopyranoside ester (1), 7β, 17-dihydroxy-entkaur-15-en-19-oic acid 19-O-β-D-glucopyranoside ester (2), 13-[(O-β-D-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O-β-Dglucopyranosyl-β-D-glucopyranosyl ester (3), 12-α-[(2-O-β-D-glucopyranosyl-β-Dglucopyranosyl)oxy]ent-kaur-16-en-19-oic acidβ-Dglucopyranosyl ester (4), glaucocalyxin G (5),β-D-glucopyranosyl 17-hydroxy-ent-kauran-19-oate-16-O-β-D-glucopyranoside (6),cussoracosides E (7), 17-O-β-D-glucopyranosyl-16α-ent-kauran-19-oic acid (8),cussovantoside A (9),cussovantoside C (10)。结论:化合物1-10首次从大瑶山甜茶中分离得到。     

Allozyme variation among Brazilian and U.S. populations ofRhyzopertha dominicaresistant to insecticides

The lesser grain borer (Rhyzopertha dominica (F.)) is an important pest of stored grain in many parts of the world (Paleartic, Ethiopian, Oriental, Australian, Neotropical, and Neartic regions) with the ability to fly long distances. These insects have been shown to be resistant to organophosphorus insecticides in several studies. Polyacrylamide gel electrophoresis was used to assess the genetic variability within and among eight Brazilian and seven United States populations of R. dominica and to determine how insecticide resistance may be spreading within both countries. Significant variation in allele frequency among populations was observed at all six polymorphic enzyme loci that were examined. The Brazilian and U.S. populations were genetically differentiated from one another; populations within the U.S. and those within Brazil were also differentiated from one another. The mean genetic similarity among the seven U.S. populations collected in a small region in northeast Kansas was smaller than that among eight Brazilian populations collected in a relatively large geographical area. These results are consistent with the resistance ratios to chlorpyriphos-methyl in R. dominica populations from Brazil and the U.S. and the information available concerning patterns of flight activity in this insect.     

Characterization of polysaccharides from Hypnea spinella (Gigartinales) and Halopithys incurva (Ceramiales) and their effect on RAW 264.7 macrophage activity

Red algae have been reported to be an important source of polysaccharides with potential immunomodulatory properties. The objective of this study was to characterize the polysaccharides from Halopithys incurva and Hypnea spinella and to evaluate their effect on the synthesis of cytokines by murine cell line RAW 264.7 macrophages. Polysaccharides were obtained by N-cetylpyridinium bromide precipitation and characterized by Fourier transform-infrared spectroscopy. Their effect on the activity of RAW 264.7 macrophages was examined by quantification of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and nitric oxide (NO) production using enzyme-linked immunosorbent assays. The activation of the cytokine IL-6 and NO increased linearly as the concentration of polysaccharides from H. incurva and Hy. spinella increased. In general, the activation of IL-6 and NO was tenfold greater when macrophages were exposed to polysaccharides from H. incurva than when exposed to polysaccharides from Hy. spinella. In contrast, TNF-α concentration did not increase when macrophages were exposed to increasing polysaccharide levels. These results indicate that polysaccharides are strong cytokine IL-6 inducers.     

Immune response of rainbow trout (Oncorhynchus mykiss) to antigenic preparations fromVibrio anguillarumserogroup O1

The humoral and cellular immune responses of rainbow trout were investigated following injection with formalin-killedVibrio anguillarumin Freund's incomplete adjuvant (FIA) in terms of reactivity towards different antigen preparations of the bacterium. Vaccinated fish were compared with control fish that had been injected only with FIA. The antigen preparations used for the comparative studies were formalin-killed bacteria, extracellular products (ECP), outer membrane proteins (OMP) and cytoplasmic membrane proteins (CMP). Humoral antibody as measured by ELISA was detected with all antigen preparations. As evaluated by ELISPOT and by proliferation assays, leucocytes isolated from vaccinated fish reacted most strongly with the OMP preparation. This observation suggests the existence of undefined potent antigenic components among these proteins. In proliferation assays, the tested antigen preparations contained components that were mitogenic to cell cultures from unvaccinated fish. However, in terms of antibodies measured by ELISA and ELISPOT techniques, only vaccinated fish reacted with theV. anguillarumpreparations.     

Impact of AMPEP on the growth and occurrence of epiphytic Neosiphonia infestation on two varieties of commercially cultivated Kappaphycus alvarezii grown at different depths in the Philippines

Two varieties of the carrageenophyte Kappaphycus alvarezii (Tungawan, TUNG; and Giant tambalang, GTAM) from Zamboanga Sibugay, Philippines were used to test the efficacy of Acadian Marine Plant Extract Powder (AMPEP) as source of nutrients for growth, and to determine if applications had any effect on the percent occurrence of an epiphytic infestation of the red alga Neosiphonia sp. at four different depths in the sea. Results showed that the use of AMPEP significantly (P < 0.05) increased the growth rate of both Kappaphycus varieties tested but decreased the percent occurrence of Neosiphonia sp. The percent occurrence of Neosiphonia sp. infection (6–50% at all depths) of both Kappaphycus varieties with AMPEP treatment was significantly lower than the controls (i.e., 10–75% at all depths). Both the growth rate of the cultivated seaweed and the percent occurrence of the epiphytes decreased as the cultivation depth increased. Plants dipped in AMPEP and suspended at the surface had the highest growth rates (i.e., 4.1%, TUNG; 3.1%, GTAM) after 45 days; those without AMPEP dipping had the highest percent occurrence of Neosiphonia infection (viz. 70–75%). The occurrence of Neosiphonia infestation was found to be correlated with changes in irradiance and salinity at the depths observed. The results suggested that both varieties of K. alvarezii used in this study have the fastest growth rate when grown immediately at the water surface. However, in order to minimize damage caused by the occurrence of epiphytic Neosiphonia, K. alvarezii should be grown within a depth range of 50–100 cm. These observations are important for the improved management of Kappaphycus for commercial farming. Furthermore, the use of AMPEP treatments for enhancement of growth and reduction deleterious Neosiphonia sp. infections is encouraging.     

Splenic cultures from rainbow trout,Oncorhynchus mykiss: establishment and characterisation

This study describes the culture conditions and the phenotypic features of different types of splenic cultures established from explants. Using the same culture technique it was possible to grow splenic explants from which monolayers of reticular origin, long-term haematopoietic cultures, and subcultures were obtained. The cultures were characterised by light and electron microscopy, cytochemical and immuno-cytochemical analyses, phagocytic activity and susceptibility to virus. The cultures comprised multilayers of epithelioid and fibroblastoid cells with haemopoietic foci, melanomacrophages and eosinophilic granular cells. The cytochemical and immuno-cytochemical analyses revealed that the stromal cells were always positive for ANAE activity. The stromal cells in primary cultures were negatively or weakly stained by antibodies directed against cytokeratins and S-100, but in the subcultures they were strongly stained by these antibodies. The stromal cells had very poor phagocytic activity and were susceptible to VHS virus.