Pseudomonas duriflava sp nov., isolated from a desert soil

A Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, designated strain HR2(T) was isolated from a soil sample from the Talklimaken Desert in Xinjiang Province, China. Strain HR2(T) grew optimally at pH 7.0-8.0 and 30-37 degrees C in the presence of 0-1% (w/v) NaCl. An analysis of 16S rRNA gene sequences revealed that strain HR2(T) fell within the radiation of the genus Pseudomonas, the highest level of similarity being found with respect to Pseudomonas luteola IAM 13000(T) (97.5%); the levels of sequence similarity with respect to other recognized Pseudomonas species were < 96.4%. DNA-DNA hybridization showed that the genetic relatedness between strain HR2(T) and P. luteola IAM 13000(T) was 53.2%. The G + C content of the genomic DNA of strain HR2(T) was 55.2 mol%. The major fatty acids were 18: 1, summed feature 3 and 16:0. The hydroxylated fatty acids 10:0 3-OH, 12:0 3-OH and 12:0 2-OH were also present. The data obtained in this polyphasic study indicated that this isolate represents a novel species of the genus Pseudomonas, for which the name Pseudomonas duriflava sp. nov. is proposed, The type strain is HR2(T) (=KCTC 221129(T) =CGMCC 1.6858(T)).

Sphingobacterium siyangense sp nov., isolated from farm soil

The taxonomic position of a novel Gram-negative strain, designated Sy1(T), isolated from a farm-soil sample obtained from Jiangsu Province, PR China, was characterized by using a polyphasic approach. The cells were non-motile, non-spore-forming rods. The organism grew optimally at 30-37 degrees C and at pH 6.0-8.0. Based on 16S rRNA gene sequence analysis, strain Sy1(T) is a member of the genus Sphingobacterium; Sphingobacterium multivorum JCM 21156(T) was the nearest relative (98.5% sequence similarity). The predominant fatty acids of strain Sy1T were isoC15:0 (32.90/o), C16:0 (10.9%) and summed feature 3 (iso-C-15:0 2-OH and/or C-16:1 omega 7c; 24.1%). The DNA G + C content was 38.5 mol%. The low level of DNA-DNA relatedness (2.2 %) to S. multivorum JCM 21156 T in combination with differential morphological and biochemical properties demonstrated that strain SY1(T) (=KCTC 22131(T)= CGMCC 1.6855(T)) should be classified as representing a novel species of the genus Sphingobacterium for which the name Sphingobacterium siyangense sp. nov. is proposed.

Flavobacterium anhuiense sp nov., isolated from field soil

A novel strain, D3(T), isolated from a field-soil sample obtained from Anhui Province, PR China, was characterized taxonomically by using a polyphasic approach. The cells were Gram-negative, yellow-pigmented rods devoid of flagella, but showing gliding motility. The organism was able to grow at 5-37 degrees C and at pH 4.0-10.0. A comparative 16S rRNA gene sequence analysis indicated that strain D3(T) is a member of the genus Flavobacterium, sharing highest sequence similarity with the type strain of Flavobacterium defluvii (96.7 %). The major isoprenoid quinone was MK-6 and the predominant fatty acids were iso-C-15:0, summed feature 3 (C-16:1 omega 7c and/or iso-C-15:0 2-OH) and C-16:0. The DNA G + C content was 31.4 mol%. On the basis of phylogenetic and phenotypic data, strain D3(T) represents a novel species within the genus Flavobacterium, for which the name Flavobacterium anhuiense sp. nov. is proposed. The type strain is D3(T) (=KCTC 22128(T)= CGIVICC 1.6859(T)).

藤三七中一个新黄烷醇和抗HIV活性成分

利用各种色谱(硅胶和凝胶)方法,从藤三七[Boussingaultia gracilis Miers var.pseudobaselloides Bailey]的70%(体积分数)的乙醇提取物中分离得到2个黄烷醇类化合物(1,2)和4个黄酮类化合物(3～6).采用UV,IR,MS 和1D,2D NMR方法,分别鉴定出如下化合物: 7-羟基-5-甲氧基-8-甲基-6-甲酰基-3,4-黄烷二醇,命名为藤三七醇A(1);4,7-二羟基-5-甲氧基-8-甲基-6-甲酰基黄烷(2);7-O-methylunonal(3);5,7-二羟基-6,8-二甲基-2-苯基-4H-1-苯并吡喃-4-酮(4);Desmosflavone(5)和Demethoxymatteucinol(6).其中化合物1是一个新的黄烷二醇化合物,化合物2～6为首次从该植物中分离得到.抗HIV-1活性筛选结果表明: 化合物1,2,5,6对HIV-1诱导合胞体的形成具有一定的抑制作用,其半数有效浓度(EC50)分别为45.09,48.73,55.47 和 82.75 μmol/L,治疗指数(TI)分别为1.41,1.20,7.15 和》8.51.

Protein three-dimensional structural databases: Domains, structurally aligned homologues and superfamilies

This paper reports the availability of a database of protein structural domains (DDBASE), an alignment database of homologous proteins (HOMSTRAD) and a database of structurally aligned superfamilies (CAMPASS) on the World Wide Web (WWW). DDBASE contains information on the organization of structural domains and their boundaries; it includes only one representative domain from each of the homologous families. This database has been derived by identifying the presence of structural domains in proteins on the basis of inter-secondary structural distances using the program DIAL [Sowdhamini & Blundell (1995), Protein Sci. 4, 506-520]. The alignment of proteins in superfamilies has been performed on the basis of the structural features and relationships of individual residues using the program COMPARER [Sali & Blundell (1990), J. Mol. Biol. 212, 403-428]. The alignment databases contain information on the conserved structural features in homologous proteins and those belonging to superfamilies. Available data include the sequence alignments in structure-annotated formats and the provision for viewing superposed structures of proteins using a graphical interface. Such information, which is freely accessible on the WWW, should be of value to crystallographers in the comparison of newly determined protein structures with previously identified protein domains or existing families.

脱抗原牛角胎骨移植家兔后的特异性免疫反应

目的 研究脱抗原水牛角胎移植后的免疫排斥反应和成骨效应。方法 以日本大耳白兔为动物模型，分别植入经30% H_2O_2、0.6 mol/L HCl脱抗原脱钙，30% H_2O_2脱抗原不脱钙2种温和方法处理的水牛角胎至兔左侧肢骨缺损处。体外检测外周血特异性T淋巴细胞转化率和ELISA检测血清特异性抗角胎IgG抗体。结果 脱抗原脱钙处理显著地降低了角胎的抗原性，与对照相比，未见受体对移植物产生显著的特异性细胞和体液免疫反应（P > 0.05），尤其是脱抗原不脱钙角胎效果更佳。两者成骨效果均良好。结论 脱抗原角胎是一种免疫原性低、成骨效果好、来源方便的骨移植材料。

γ-氨基丁酸受体和甘氨酸受体在大鼠丙泊酚麻醉中的作用

目的 研究丙泊酚对大鼠海马CA1区电刺激诱发兴奋性突触后电流(EPSC)的影响,分析γ-氨基丁酸(GABA)受体和甘氨酸受体在丙泊酚麻醉中的作用.方法 断头法分离wistar大鼠(13～19 d)海马半脑,切出400 μm厚度的海马脑片,全细胞膜片钳技术记录CA1区锥体神经元EPSC.80张脑片分为八组:脂肪乳剂组,50 μmol/L丙泊酚组,100 μmol/L丙泊酚组,200 μmol/L丙泊酚组,SR95531组,士的宁组,SR95531+100 μmol/L丙泊酚组,士的宁+100 μmol/L丙泊酚组,每组10张.SR95531+100 μmol/L丙泊酚组和士的宁+100 μmol/L丙泊酚组先在循环液中加入10 μmol/L SR95531或4 μmol/L士的宁预孵脑片30 min.八组均记录基础EPSC 10 min,然后加入不同药物,继续记录EPSC 40 min.膜钳制电压为-70 mV.结果 脂肪乳剂、SR95531和士的宁对EP-SC幅值无影响;丙泊酚呈剂量依赖性的抑制EPSC幅值,50、100、200 μmol/L丙泊酚最大抑制EPSC幅值为14.4%、52.3%、67.8%;SR95531+100 μmol/L丙泊酚组加入丙泊酚后,EPSC幅值基本无改变;士的宁+100 μmol/L丙泊酚组加入丙泊酚后,EPSC幅值仍然下降,最大抑制程度为34.7%.结论 丙泊酚主要通过增强GABAA受体功能使兴奋性突触活动降低,甘氨酸受体在其中起到协同和调节作用.

异丙酚对大鼠海马CAl区神经元兴奋性突触传递的影响

目的研究异丙酚对大鼠海马CA1区神经元兴奋性突触后电流(EPSC)和自发性兴奋性突触后电流(sEPSC)的影响。方法 Wistar大鼠断头后分离海马脑组织,制成400μm厚度的海马脑片,脑片随机分为5组(n=10)。脂肪乳剂Ⅰ组、异丙酚Ⅰ组、SR95531+异丙酚组:记录EPSC 10 min (基础值)后分别加入10％脂肪乳剂90μl、1％异丙酚90μl(相当于100μmol／L)、10μmol／L SR95531+100 μmol／L异丙酚,继续记录EPSC 40 min,分析EPSC幅值的变化。脂肪乳剂Ⅱ组、异丙酚Ⅱ组:细胞破膜后稳定10-15 min,分别加入10％脂肪乳剂90μl和1％异丙酚90μl,记录sEPSC 40 min,分析sEPSC频率、幅值和半衰期的变化。膜钳制电压均为-70 mV。结果与基础值比较,给药后脂肪乳剂Ⅰ组和 SR95531+异丙酚组EPSC幅值差异无统计学意义,异丙酚Ⅰ组EPSC幅值降低;给药后异丙酚Ⅰ组 EPSC幅值比脂肪乳剂Ⅰ组降低(P<0．05)。与脂肪乳剂Ⅱ组比较,异丙酚Ⅱ组sEPSC的频率、幅值降低、半衰期缩短(P<0．05)。结论异丙酚主要通过增强大鼠海马CA...

异丙酚对大鼠海马CAI区自发性兴奋性突触后电流的影响

目的:研究异丙酚对大鼠海马CA1区自发性兴奋性突触后电流(sEPSC)的影响。方法:断头法分离Wistar大鼠(13~19 d)海马半脑,用切片机切出400μm厚度的海马脑片,全细胞膜片钳记录CA1区锥体神经元sEPSC。20张脑片分为两组:脂肪乳剂组(n=10)和异丙酚组(n=10)。两组细胞稳定10~15 min后,加入90μl脂肪乳剂或异丙酚(相当于100μmol/L),记录40 min sEPSC。膜钳制电压为-70 mV。结果:100μmol/L异丙酚降低sEPSC的频率达68.1%,降低sEPSC的幅值达29.1%,缩短sEPSC的半衰期达49.3%;另外,异丙酚缩短sEPSC的上升时间达29.1%,减少曲线下面积达74.7%。结论:异丙酚通过影响突触前膜递质释放和突触后膜受体功能两个因素抑制兴奋性突触活动

丙泊酚对大鼠海马CA1 区兴奋性突触传递的影响

　目的　观察500μmol/ L 丙泊酚对大鼠海马CA1 区电刺激诱发的兴奋性突触后电流 ( EPSC) 的影响,分析丙泊酚的可能作用机制。方法　断头法分离Wistar 大鼠(13～19 d) 海马半脑, 用切片机切出400μm 厚度的海马脑片,全细胞膜片钳技术记录CA1 区锥体神经元EPSC。实验分 两组:脂肪乳剂组( n = 6) 和丙泊酚组( n = 10) 。先以50μmol/ L 印防己毒素预孵脑片30 min 后,记录 基础EPSC 10 min ,然后加入450μl 脂肪乳剂或丙泊酚(相当于500 μmol/ L ) , 继续记录EPSC 40 min ;继而以配对刺激代替单刺激,观察EPSC2/ EPSC1 比率的变化;改变膜钳制电压( - 80～ + 60 mV) ,观察电流2电压( I2V) 曲线的变化。结果　脂肪乳剂对EPSC 无影响,500μmol/ L 丙泊酚降低 大鼠海马CA1 区EPSC 值,25～30 min 左右达最大抑制效果,EPSC 幅值下降至基础值的6715 % ,明 显低于脂肪乳剂组( P < 0105) ;而且500μmol/ L 丙泊酚明显降低EPSC2/ EPSC1 比率,也使I2V 曲线 左移,降低反转电位至- 35 mV 左右。结论　500μmol/ L 丙泊酚对大鼠海马CA1 区兴奋性突触传 递产生抑制作用,这可能与其增强突触前膜、突触后膜GABAA 受体活性有关。

丙泊酚对大鼠海马CA1 区长时程抑制的影响

　目的　观察丙泊酚对大鼠海马CA1 区锥体神经元产生的长时程抑制(L TD) 的影响,并 分析其可能机制。方法　断头法分离wistar 大鼠(13～19 d) 海马半脑,用切片机切出400μm 厚度的 海马脑片。实验分三组:脂肪乳剂组( I 组) ,丙泊酚组(P 组) ,SR95531 + 丙泊酚组( GP 组) 。I 组和P 组以90μL 脂肪乳剂或丙泊酚(相当于100μmol/ L) 预孵脑片60 min ,然后给予低频刺激(L FS) ,记录 L TD 的表达情况; GP 组先在循环液中加入10μmol/ L SR95531 预孵脑片30 min ,再加入100μmol/ L 丙泊酚继续孵育60 min ,继而给予L FS ,记录L TD 的表达情况。结果　I 组给予L FS 后,产生L TD , L FS 后10～40 min 的兴奋性突触后电流( EPSC) 值为基础值的57185 %;P 组给予L FS 后10～40 min 的EPSC 值为基础值的40182 % ,明显低于I 组( P < 0105) ; GP 组给予L FS 后10～40 min 的EPSC 值为基础值的56151 % ,与I 组比较差异无显著意义( P > 0105) ,与P 组比较差异有显著意义( P < 0105) 。结论　100μmol/ L 丙泊酚使大鼠海马CA1 区锥体神经元L TD 表达增强,这种作用与其增强 GABAA 受体功能有关;当阻断GABAA 受体后,这种易化作用消失。

Effect of Pyrethrins and Rosemary on the ATPase Activities of Rat Cerebral Synaptosome

除虫菊酯越来越广泛地被应用于农业和家庭昆虫防治,主要通过作用于膜结合蛋白而对动物起神经毒性.迷迭香因其抗氧化功能而被应用于很多商业化的除虫菊酯产品中.本实验以大鼠大脑突触体ATP酶为研究对象,对除虫菊酯和迷迭香的药理学进行了研究.用Percoll梯度离心法分离突触体,通过检测无机磷的量来测定总ATP酶和Mg2+-ATP酶活性.结果表明,除虫菊酯在浓度为10 μmol/L时总ATP酶和Mg2+-ATP酶分别降低到对照的80.3%和46.9%.迷迭香在浓度为0.3～30 μmol/L时几乎不影响ATP酶活性,当浓度上升到3 000 μmol/L时,总ATP酶活性降低到66.8%,而Mg2+-ATP酶活性降低到54.5%. 10 μmol/L 除虫菊酯和30 μmol/L迷迭香混合物引起总ATP酶和Mg2+-ATP酶分别降低到72.9%和33.4%.结论: 1) 除虫菊酯能抑制大鼠大脑ATP酶活性; 2) 迷迭香只在高浓度下才对ATP酶有抑制作用; 3) 迷迭香能增强除虫菊酯对ATP酶的抑制作用.图3参19

补充营养对柑橘凤蝶卵成熟和雄虫寿命的影响

在实验室条件下,定量地研究了蔗糖、葡萄糖、果糖和蜂蜜等4种补充营养物对柑橘凤蝶卵成熟和雄虫寿命的影响.结果表明:(1)补充蔗糖、果糖和蜂蜜水的雌虫孕成熟卵量都显著高于清水对照组,其中补充蔗糖的雌虫孕成熟卵量最高;(2)不同的补充营养物对雌虫孕亚成熟卵量和未成熟卵量的影响不显著;(3)饲喂蔗糖、果糖和蜂蜜的雄虫寿命显著高于对照组,其中饲喂果糖的雄虫寿命最长;(4)饲喂添加不同浓度NaCl溶液的蜂蜜水的雄虫寿命比仅饲喂蜂蜜水的雄虫短,当NaCl溶液浓度为0.001 mol/L,0.1 mol/L和 1 mol/L 时,雄虫寿命显著低于对照,其中饲喂0.001 mol/L NaCl溶液的雄虫寿命最短.