Insertional Mutation on Mouse Chromosome 18 with Vestibular and Craniofacial Abnormalities

A dominant mutation was generated in transgenic mice as a consequence of insertional mutation. Heterozygous mice from transgenic line 9257 (Tg(9257)) are hyperactive with bidirectional circling behavior and have a distinctive facial appearance due to hypoplasia of the nasal bone. Morphological analysis of the inner ear revealed asymmetric abnormalities of the horizontal canal and flattening or invagination of the crista ampullaris, which can account for the circling behavior. The sensory epithelium appeared to be normal. The transgene insertion site was localized by in situ hybridization to the B1 band of mouse chromosome 18. Genetic mapping in an interspecific backcross demonstrated the gene order centromere--Tg(9257)--8.8 +/- 3.4--Grl-1, Egr-1, Fgf-1, Apc--14.7 +/- 4.3--Pdgfr. The phenotype and the mapping data suggest that the transgene may be inserted at the Twirler locus. Homozygosity for the transgene results in prenatal lethality, but compound heterozygotes carrying the Tw allele and the transgene are viable. The function of the closely linked ataxia locus is not disrupted by the transgene insertion. This insertional mutant will provide molecular access to genes located in the Twirler region of mouse chromosome 18.     

Effect of shock-loading of heavy metals on total organic carbon and phosphate removal in an anaerobic-aerobic activated sludge process

The effect of shock-loading of zinc, copper and cadmium ions on the removal of total organic carbon (TOC) and phosphate in an anaerobic-aerobic activated sludge process was investigated. TOC removal was not sensitive to shock-loading of Zn²⁺ and Cd²⁺ ions, and complete removal was achieved even at 20 mg Zn²⁺/l and 20 mg Cd²⁺/l. However, with over 1 mg Cu²⁺/1 TOC removal efficiency decreased. PO _inf4 ^sup3- removal, in contrast, was extremely sensitive to these metal ions, with the threshold being 1 mg Zn²⁺/l and 1 mg Cd²⁺/l. Higher concentrations adversely affected PO _inf4 ^sup3- removal. Copper again proved detrimental; no PO _inf4 ^sup3- removal was achieved even at 1 mg Cu/l. These results highlight the sensitivity of the removal efficiencies of TOC and PO _inf4 ^sup3- to shock loadings of these heavy metals.Y.P. Ting is with the Department of Chemical Engineering, National University of Singapore, Kent Ridge, 0511, Singapore; H. Imai and S. Kinoshita are with the Department of Chemical Process Engineering, Hokkaido University, Sapporo 060, Japan.     

质体醌重组的D1／D2／Cytb559复合物的荧光衰减动力学和光破坏作用

光系统Ⅱ反应中心Ｄ１／Ｄ２／Ｃｙｔｂ５５９ 在分离纯化过程中失去了电子受体ＱＡ 和ＱＢ,人工合成的质体醌可以与Ｄ１／Ｄ２／Ｃｙｔｂ５５９ 复合物发生重组。癸基质体醌（ＤＰＱ）与Ｄ１／Ｄ２／Ｃｙｔｂ５９９ 复合物的重组导致该复合物的荧光强度下降及发射光谱蓝移,同时两个与光化学活性相关的长寿命（２４ ｎｓ和７３ ｎｓ）荧光衰减组分占整个荧光的百分数下降,这些结果表明ＤＰＱ作为Ｐｈｅｏ－ 的电子受体,限制了Ｐ６８０＋ ·Ｐｈｅｏ－ 的电荷重组。ＤＰＱ 的加入对Ｄ１／Ｄ２／Ｃｙｔｂ５５９复合物中Ｃｈｌａ 分子的光破坏敏感性影响不大,但β－胡萝卜素在加入ＤＰＱ 之后可以被光照破坏,这个过程可能与β－胡萝卜素的生理功能相关。     

河北小五台山叶生丝孢菌

小五台山自然保护区位于河北省西部,为河北省第一高峰。变化悬殊的地形,使其由低谷到亚高山草甸呈明显独特的垂直植被类型分布带,山势陡峻,谷路隘险,具有华北地区罕见的森林植被及丰富的植物资源。狭谷陡峰,葳蒐险奇的地形地貌,又形成了多变的气候特征,因此蕴藏着相当丰富的真菌资源。作者1990年8月在该地区考察期间,共采集涉及林木、农作物、花卉、蔬菜等植物病害标本240份。本文报道小五台山的丝孢菌(Hyphomycetes)14属40种,其中有二个新种:(木来)木菌绒孢(Mycovellosiella coni Y.L.Guo, sp. nov.),五味子色链隔孢(Phaeoramularia schisandrae Y.L. Guo, sp. nov.)和7个中国新记录种:沼泽尾孢(Cercospora paludicola Speg.),白面子菌绒孢[Mycovellosiella ariae(Fuckel) U. Braun],薯蓣菌绒孢[Mycovellosiella dioscorae(Vassiljevski) Pons & Sutton],当归柱隔孢(Ramularia angelicae v. Hohnel),白芷柱隔孢[Ramularia heraclei(Oud.)Sacc.),莴苣柱隔孢(Ramularia lactucosa Lamb. & Fautr.)和虎耳草柱隔孢(Ramularia saxifragae Syd.)。(木来)来木菌绒孢(Mycovellosiella coni Y.L. Guo, sp. nov.)生于山茱萸科(Cornaceae)华尔特氏掠子木(Cornus walteri Wanger.)叶上。子实体生于叶背面。次生菌丝体表生。无子座。分生孢子梗1-3根从气孔伸出或作为侧枝单生于表生菌丝上,近无色,分枝,曲膝状,1-2个隔膜,5.0-50.0 × 2.5-4.0 μm。分生孢子圆柱形,无色,链生并具枝链,0-4个隔膜,6.5-45.0 × 2.0-4.0 μm。在山茱萸科尚无菌绒孢属的报道,且该菌与已报道的尾孢属菌形态特征也不同,故定为新种。五味子色链隔孢(Phaeoramularia schisandrae Y.L. Guo, sp. nov.)生于五味子科(Schisandraceae)五味子[Schisandra chinensis (Tunz.) Baill.]叶上,子实体生于叶背面。菌丝体内生。具子座。分生孢子梗紧密簇生,浅青黄褐色,不分枝,曲膝状,1-5个隔膜,20.0-75.0 (-95.0) × 4.0-5.0 μm。分生孢子圆柱形,近无色,链生并具枝链,1-4个隔膜,15.0-40.0 × 3.0-4.0 μm。五味子科既无尾孢菌属也无色链隔孢属的报道。文中为新种提供了拉丁文简介、描述和图,新记录种进行了简要描述。研究的标本保藏在中国科学院微生物研究所真菌标本室(HMAS)。     

气候变化导致青藏高原马鹿种群适应性分布退缩：以类乌齐马鹿国家级自然保护区为例

近50年青藏高原的气候变化速率是全球平均值的2倍,对高原有蹄类的种群分布和多样性维持带来严重影响。本研究以西藏类乌齐马鹿国家级自然保护区的马鹿种群为例,通过2013年和2021年对马鹿和牦牛种群数量、分布的调查,并整合了物种分布模型和种群动态模型,评估了当前和未来气候变化及人类活动(放牧、道路、居民点等)对马鹿种群适应性分布的影响。研究表明,马鹿种群在2013—2021年由890头增加到1 400头,根据种群增长模型预计在2050年马鹿种群数量将达到1 735头,但其适宜栖息地在2050年代下降43.4%,2070年代下降5.1%,表明马鹿种群增长与适宜栖息地缩小之间的冲突将不利于马鹿种群的可持续发展。同时,当前马鹿与牦牛栖息地重合率为19%,2050年代为60%,2070年代为37%,且牦牛与马鹿存在食物竞争,这在一定程度上减少了马鹿原有的适宜栖息地。为保护马鹿,建议减少牦牛的饲养量1 000～1 500头。本研究将种群增长模型、种间竞争关系与物种分布模型整合,把气候变化对物种的影响延伸到种群层面,对其他物种的保护具有借鉴意义。     

烟草品种、育苗方式和烟蚜来源对烟蚜茧蜂寄生能力的影响

【目的】本研究旨在筛选出适合烟蚜茧蜂Aphidius gifuensis寄生烟蚜Myzus persicae的烟草品种、育苗方式和烟蚜来源,为烟蚜茧蜂人工繁殖和复壮提供科学参考。【方法】采用盆栽法,调查了不同烟草品种(云烟87、K326、翠碧1号和红花大金元)繁殖烟蚜若蚜、不同来源烟蚜(来自烟区、来自非烟区和室内繁殖种群)若蚜和烟草不同育苗方式(土壤育苗和湿润育苗)繁殖烟蚜若蚜时,烟蚜茧蜂成蜂对烟蚜若蚜的寄生率以及成蜂羽化率、寿命、体型大小和雌蜂比。【结果】结果表明,不同烟草品种繁殖烟蚜若蚜对烟蚜茧蜂成蜂寄生率存在显著影响。其中,在红花大金元和翠碧1号繁殖烟蚜上的烟蚜茧蜂成蜂寄生率分别比在K326繁殖烟蚜上的烟蚜茧蜂成蜂寄生率高19.00%和14.00%,但对烟蚜茧蜂的其他指标没有显著影响;不同烟蚜来源对烟蚜茧蜂寄生率也存在显著影响,其中,烟蚜茧蜂成蜂对非烟区烟蚜若蚜和烟区烟蚜若蚜的寄生率比对室内繁殖种群烟蚜若蚜的寄生率分别高20.25%和16.75%,但对烟蚜茧蜂成蜂的羽化率、寿命、体型大小和雌蜂比没有显著影响;烟草不同育苗方式对烟蚜茧蜂成蜂的寄生率无显著影响。【结论】烟蚜茧蜂对烟蚜...     

慢性心功能不全大鼠心脏和血淋巴细胞β-肾上腺素受体的改变

在主动脉与肾动脉缩窄造成的慢性心功能不全大鼠,血浆儿茶酚胺浓度增高;心脏β-肾上腺素受体(β-AR)数量增加,其中β_1-AR及其mRNA增加,而β_2-AR及其mRNA不变;左心房异丙基肾上腺素(ISO)浓度-收缩效应曲线右移;而心肌ISO浓度-cAMP蓄积曲线无显著改变;血淋巴细胞β-AR数量显著减少.结果提示心功能不全时心脏β_1-AR数量增多,但其介导的正性变力效应反而降低,在cAMP生成以后的信号转导过程或心肌收缩成分功能存在障碍,而血淋巴细胞β-AR的改变与心脏β-AR的功能改变平行.     

Differential requirement of protein tyrosine kinase and protein kinase C in the generation of IL-2-induced LAK cell and αCD3-induced CD3-AK cell responses

This study examined the role of protein tyrosine kinase (PTK) and protein kinase C (PKC) in the signal transduction pathways for lymphocyte activation through IL-2R to generate LAK cells and through TCR—CD3 to generate CD3-AK cells. Two PTK inhibitors [herbimycin A and genistein (PTK-I)] and two PKC inhibitors [calphositin C and staurosporine (PKC-I)] were used in the experiments. It was found that the primary activation pathway through IL-2R was PTK-dependent; that is, generation of both the IL-2-induced proliferative and the cytotoxic responses was completely abrogated by PTK-I and not by PKC-I. Quite different results were obtained with the αCD3-induced CD3-AK cell response. First, the αCD3-induced proliferation was only partially inhibited by PTK-I or PKC-I alone. Second, generation of CD3-AK cytotoxic response was primarily PKC-dependent; that is, only PKC-I induced significant inhibition. Genistein was found to reduce protein tyrosine phosphorylation in both LAK cells and CD3-AK cells, indicating that CD3-AK cells were also susceptible to PTK-I treatment. Further studies showed that PTK-I and not PKC-I suppressed perforin mRNA expression and N-2-benzyoxycarbonyl-l-lysine thiobeneylester esterase production in LAK cells, and the opposite was true for CD3-AK cells. These results indicate that different pathways were employed in lymphocyte activation through IL-2R and TCR—CD3. The former pathway is primarily PTK-dependent. Activation through TCR—CD3 is a more complex event. Induction of a proliferative response can employ either a PTK- or a PKC-dependent pathway, whereas induction of a cytotoxic response is primarily PKC-dependent. Furthermore, it appears that a PTK-independent pathway exists for the induction of a CD3-AK response and thus suggests that activation of the second messenger PKC may not necessarily be preceded by PTK activation.