Micropropagation of a medicinal plant, Plantago major L.

An efficient micropropagation protocol was developed for an important medicinal plant, Plantago major L. For this purpose, it is recommended to culture shoot-tips on modified MS medium [412.5 mg dm-3 NH4NO3 and 340 mg dm-3 KH2PO4] supplemented with 50 g dm-3 glucose and 0.5 μM 6-benzylaminopurine. Maximum rooting frequency was obtained at 1 μM naphthaleneacetic acid. This revised version was published online in August 2006 with corrections to the Cover Date.     

中国锥属(壳斗科)一新记录种——巨盘锥

【目的】巨盘锥(Castanopsis grandicicatricata)是原产于越南中、北部的壳斗科锥属植物,现于云南屏边苗族自治县大围山地区发现一零星分布的居群。为确定该种的身份,检验原始文献基于形态学推测的近亲,并展示该种所处的系统地位。【方法】利用细胞核rRNA基因5.8S、26S间隔区ITS2与叶绿体基因rbcL分子标记重建系统树。【结果】形态上,该种壳斗4.5～6.0 cm,刺树状分枝,坚果扁球形,果脐占坚果表面积2/3,与中国已知锥属均不同。分子系统树支持形态学推测,湄公锥(C.mekongensis)是其近缘种之一。【结论】巨盘锥是中国锥属一新记录种,这对于研究中国滇东南与越南北部植物区系有重要的意义。     

一株Streptosporangium sp.次生代谢产物研究Ⅰ

通过对Streptosporangium sp．菌株发酵液的初步分离纯化,得到三个化合物,由波谱解析鉴定为：4,6-二甲基-6-羟基-庚烯-2酮(1),2,6-二甲基-2,6-二羟基-庚4酮(2),3,6-二异丙基-2,5-二酮哌嗪(3)。由活体试验证明2和3对粘虫有一定的抑制活性。     

In vitro adaptation of a ligase ribozyme for activity under a low-pH condition.

A ligase ribozyme accelerating a ligation reaction with oligonucleotide under a low-pH condition was selected by in vitro adaptation. A ribozyme active at pH 7 was randomly mutated, and the resultant RNA library was subjected to in vitro adaptation under a low-pH reaction condition. At pH 4, the adapted RNAs reacted with the oligonucleotide substrates about 200 times faster than the original ribozyme. When the ribozyme was cloned and sequenced, 10 of the 30 clones sequenced had identical sequences. The differences in sequence from the original ribozyme were found at four positions in the middle region and at the 3' end. A few sequential differences dominated the activity of the ribozyme under the extreme condition. The adapted ribozyme had one repeating sequence that was critical for the activity.     

Carotenoids in fish. XX. Carotenoids in Salmo gairdneri rich. And Salmo trutta morpha fario L.

The author investigated the presence of various carotenoids in Salmo gairdneri Rich. and Salmo trutta morpha fario L. from the trout fish farm (artificial food) and from the river as the natural conditions (natural food).The findings of these investigations indicate that the trout bred in natural conditions are richer in carotenoids, provitamins of vitamin A, than are trout from the trout fish farm. In all probability the variety of food available in natural conditions provides better facilities for the accumulation of carotenoids in the body of trout in their natural habitat.     

Development of the interferon system. I. In chicken cells development in ovo continues on time in vitro

Summary When confluent monolayers of cells derived from chicken embryos of different gestational age were cultured for several days without a medium change, a condition termed in vitro aging, the cells' developed an increased capacity to express the interferon (IFN) system. The capacity to both produce IFN and to respond to its antiviral action were enhanced up to 1000- and 100-fold, respectively. Remarkably, the programmed development of the IFN system in these cells seemed to continue virtually uninterrupted after monodispersion of the cells and seeding at high cell density. Cells prepared from young embryos required more time to develop the IFN system than cells from older embryos with the yield of IFN, and sensitivity to its action, related directly to the total in ovo and in vitro age of the cells in culture. For example, essentially the same yields of IFN were obtained from cell cultures made from 5-d-old embryos “aged” for 10 d in vitro, as were obtained from 10-d-old embryos whose cells were aged in vitro for 5 d. In contrast, inducibility of 2′–5′ oligoadenylate synthetase by IFN and the induction of heat shock genes by elevated temperature are not enhanced with in vitro aging. The programmed development of the IFN system that starts in ovo seems to continue on schedule in vitro, making the development of the IFN system in chick embryo cells appear as a time-dependent process. This study was supported by the grant RO1 AI18381 from the national Institute of Allergy and Infectious Diseases, Bethesda, MD, and benefited from services of the Cell Culture Facility of the Biotechnology Center at The Univeristy of Connecticut.     

Application of a simple culture of Plasmodium berghei for assessment of antiparasitic activity.

and 1992. Application of a simple culture of Plasmodium berghei for assessment of antiparasitic activity. International Journal for Parasitology 22: 1137–1142. Mouse erythrocytes infected with Plasmodium berghei were incubated for a short period in microplate wells. The parasites changed morphologically from the immature ring form to mature schizonts, and free merozoites were released. However, reinvasion of the erythrocytes appeared not to be possible in this system. This intraerythrocytic one-step growth of the parasite could be determined quantitatively by counting incorporation of 'H-hypoxanthine. The incorporation was markedly decreased by addition of certain antiparasitic agents to the culture. The sensitivity of this growth inhibition test was comparable to or higher than the mouse protection test. The results suggested the practical utility of this simple assay in screening antimalarial activity.     

Abbreviations and symbols in peptide science: a revised guide and commentary.

The abbreviations and symbols used in Peptide Science are surveyed, with comment and recommendations.     

香蕉枯萎病菌4号生理小种致病相关基因foABC1的分离

通过对香蕉枯萎病菌4号小种致病突变体B1233的进一步研究,分离了被突变的致病相关基因foABC1,同源性分析及保守结构预测该基因编码一类ABC转运蛋白,其功能可能同稻瘟病菌的ABC转运蛋白一样,负责真菌毒素的泵出,或是像其他真菌的ABC转运蛋白,在病原菌侵染寄主植物时能忍耐植物因防卫反应所释放的植保素或抗毒素类物质。     

草木樨状黄芪高频离体再生体系的建立

以草木樨状黄芪无菌苗茎切段为材料,在含１－２mg/L2,4-D和０－０．５mg/L６ＢＡ的MS培养基上培养获得大量愈伤组织,愈伤组织诱导率在９５％以上,愈伤组织在附加０．２mg/LＫＴ,１mg/L６ＢＡ,０或０．５mg/LＮＡＡ,５００mg/LＣＨ 和２００mg/L ＹＥ的ＭＳ培养基上诱导丛生芽,并进而发育成苗。苗的分化频率为１００％。分化苗或其茎的切段在不国源植物激素的１／２ＭＳ培养基上可出现根的分化,分化频率达９０％以上,再生植株经炼苗后移栽成活率达８０％以上。     

Myosin V exhibits a high duty cycle and large unitary displacement.

Myosin V is a double-headed unconventional myosin that has been implicated in organelle transport. To perform this role, myosin V may have a high duty cycle. To test this hypothesis and understand the properties of this molecule at the molecular level, we used the laser trap and in vitro motility assay to characterize the mechanics of heavy meromyosin-like fragments of myosin V (M5(HMM)) expressed in the Baculovirus system. The relationship between actin filament velocity and the number of interacting M5(HMM) molecules indicates a duty cycle of > or =50%. This high duty cycle would allow actin filament translocation and thus organelle transport by a few M5(HMM) molecules. Single molecule displacement data showed predominantly single step events of 20 nm and an occasional second step to 37 nm. The 20-nm unitary step represents the myosin V working stroke and is independent of the mode of M5(HMM) attachment to the motility surface or light chain content. The large M5(HMM) working stroke is consistent with the myosin V neck acting as a mechanical lever. The second step is characterized by an increased displacement variance, suggesting a model for how the two heads of myosin V function in processive motion.     

Minchinia mercenariae n. sp. (Haplosporidia) in the Hard Clam Mercenaria mercenaria: Implications of a Rare Parasite in a Commercially Important Host

ABSTRACT. During routine histopathology of 180 juvenile hard clams, Mercenaria mercenaria , from a site in Virginia, USA, in 2007, we discovered a single individual heavily infected with a parasite resembling a haplosporidian, some members of which cause lethal bivalve diseases. Scanning electron microscopy of spores and sequencing of small subunit ribosomal DNA confirmed a new species: Minchinia mercenariae n. sp. Further sampling of clams at the site found prevalences up to 38% using polymerase chain reaction (PCR). No parasites were found in routine histological screening of the same individuals, but re-examination of clams judged positive by in situ hybridization (ISH) revealed very faintly staining plasmodia. No unusual mortalities have occurred among the sampled groups. Analysis of clams from Massachusetts to Florida by PCR failed to detect the parasite, but a haplosporidian found in a clam from New Jersey in 2001 was subsequently identified by ISH as M. mercenariae . No other haplosporidians have been reported in thousands of hard clams from the US east coast examined histologically since the mid-1980s. The discovery underscores critical questions about how to assess the risks associated with parasites in groups known to be lethal, but that themselves are not considered a problem.     

Prolegomenon for a hypothesis on music as expression of an evolutionary early homeostatic feedback-mechanism. A biomusicological proposal.

Musical experience and creativity are regarded to be largely depending on cultural conditions and hence on higher cognitive functions. True as this may be, there are, however, numerous responses to music-the urge to make music taken into account-which derive from deeper levels of the human organism, namely from arousing alternatively moderating vegetative and limbic functions. Although the behavioral intensity and quality emanating from such evolutionary early nervous structures may be affected by cultural influence, they still seem to be essentially independent. Similar specific responses to acoustical and/or motor patterned stimuli are found among some other higher vertebrates which like humans are equipped with sophisticated mechanisms for hearing, sound production and locomotion, well tuned to each other. However, it is even today an open question whether these manifestations of auditive-phonatory-locomotor abilities just are analogues or if they share a common evolutionary background. The current discussion on this matter has accumulated data which apparently support the latter view pointing to that sexual selection would be the common force, first suggested by Charles Darwin (153). Other, and still more recent data in genetics and neuroscience, may be interpreted as hints at that the common origin would be a more elemental organismic feature, a metabolic-homeostatic variable which due to its evolutionary strength eventually created the platform for a radiation of adaptations concerning species-specific patterned sounds and locomotions with a broad spectrum of tasks, among them sexual selection. This line of reasoning is here, under reference to recent biological data, made the basis for a hypothetical model of music as an expression of an early homeostatic feedback mechanism. Accordingly, in music there is a central variable, a “heart” or a “core”, which is not to be found exclusively in music but appears globally as a releasing mechanism for basic endocrine, autonomous and elementally cognitive functions. It is of acoustical or motoric nature, or of a combination of these characters, and is performed in repetitive trains of impulses. It is further assumed that the target of its operations is mainly proteins with a regulatory effect on the cellular and synaptic states. The principal representatives for these proteins are growth factors, especially the NGF which originally was regarded as a growth stimulator within the peripheral and sympathetical systems but which eventually appeared to be also a synergetic modulator of neuro-endocrine-immuno-reactions, i.e. of the three central homeostatic systems (5, 80). One can speculate that this variable is functionally active at an elemental level such that it has escaped to be knocked out by forceful “higher” and evolutionary younger factors (49:13). This hypothesis — that music has its roots within and is a part of a globally occurring natural acoustical-motoric stimulus, manifested in a great variety of auditory and motoric behavior in humans and among some other higher vertebrates — implies that humankind has developed this stimulus into a category of acoustical structures which oscillate round an instable point of equilibrium. Exactly such structures, not stochastic but neither too predictable, affect the organism mainly on a sensory-vegetative level (59, 102, 137, 151). They are in addition perceptionally optimal in creating cortical space-temporal neural patterns with strong interhemispheric coherence (110, 130). According to this scenario, music did not originate from a human need of communication or as an aspect of sexual selection. It emerged from elemental processes within the individual organism with the aspiration to maintain his bodily and mental fitness, thus on a pre-social level. What was beneficial to the single individual in his fight for survival, was good also for the group and its survival. Starting from that platform music has evolved in symbiosis with dance and play within a large spectrum of social functions, where sexual selection and ritual and autonomously aesthetical tasks got a focal role that increased over time and always was accompanied by emotional events. Behind, the ticking in the deep structure of music of this in cultural-ethical terms totally value-neutral archaic mechanism goes on without pause, contributing to the maintenance of an optimal functional balance in body and mind of the individual, and the group as well.     

Trypanosoma cruzi: intracellular stages grown in a cell-free medium at 37 C.

A liquid medium containing a high concentration of water-soluble vitamins and ATP was developed for serial cultivation of Trypanosoma cruzi at 27–37 C; fetal bovine serum and trypticase were the only undefined substances in this medium. At 27 C, Trypanosoma cruzi grows primarily (over 99%) as epimastigotes with a population density reaching 92.7 × 10⁶/ml after 12 days of incubation. During the first subculture at 37 C, many epimastigotes from the original inocula changed into metacyclic trypomastigotes after 48 hr; the trypomastigotes subsequently transformed into amastigotes by 96 hr. In the second passage at 48 hr, 57.8% of the organisms were trypomastigotes which changed into amastigotes by the end of the incubation period. The proportion of amastigotes in the third and subsequent passages increased steadily as the proportion of epimastigotes gradually diminished. Amastigotes thus obtained could be serially subcultured indefinitely, yielding population densities of over 3.0 × 10⁷/ml of medium in 4–5 days at 37 C. Available evidence indicates that these amastigotes are morphologically and physiologically similar to intracellular amastigotes.     

Experiences in Teaching Scientific Writing in the U.S.A.

The origin and intended meaning of the phrase ‘survival of the fittest’ are discussed. The development of the concept of ‘fitness’ in a neo-Darwinian sense is traced, and the use of the term in other contexts is outlined. The treatment of ‘fitness’ in various popular biology texts is considered, and some suggestions about the use of the term in schools are made.

The relationship of interpretations of ‘fitness’ to a broader understanding of evolutionary mechanisms is stressed throughout.     

Modeling the interaction of a neutral polymer with small ions in solution. A theoretical study of ion binding to a neutral polymer

The interaction between NaCl and 1,2-dimethoxyethylene is used to model ion binding to a neutral polymer. The relative binding energies involving different ion-polymer structures were calculated using minimal basis STO-3G and split valence 3-21Gab-initio and CNDO/2 semi-empirical wavefunctions. The results obtained are consistent with an adsorption model in which the cation is primarily adsorbed on the oxygen sites. The counter ion is then bound by the charged polymer in a form consistent with an ion pair structure. These results are consistent with recent experimental studies on polyoxyethylene (POE). Additional calculations were performed to include specific interactions with the liquid environment. Electrostatic solvation effects, introduced through the self-consistent reaction field (SCRF) model, appear to be significant in the stabilization of a solvent-separated ion-pair structure. However, the global stabilization produced by both specific and electrostatic solvations predicts the preferential stabilization of an externally hydrated intimate ion pair.Dedicated to the memory of the late Professor Luis Sepulveda (1988).CMCA Contribution No 3.     

Carotenoids in fish XIV. The carotenoid content in the flesh of certain species from the Antarctic.

The authors investigated the presence of various carotenoids in the fish of certain species in the Rajidae (Raja georgiana), Muraenolepidae (Muraenolepis microps), Notothenidae rDissostichus eleginoides, Notothenia gibberifrons, Notothenid rossi-marmorata, Trematomus hansoni) and Chaenichthyidae (Chaenocephalus aceratus, Champsocephalus gunnari, Pseudochaenichthys georgianus) family from the Antarctic by means of columnar and thin-layer chromatography.The following carotenoids were identified: ß-carotene, -cryptoxanthin, canthaxanthin, flavoxanthin, isozeaxanthin, zeaxanthin, tunaxanthin, lutein-5, 6-epoxide, aurochrome, aurochrome-like, auroxanthin, astaxanthin, astaxanthin ester and 4-hydroxy--carotene.The total carotenoid content of this fishes was from 0.066 to 0.122 µg/g fresh weight.     

Purification and Properties of Catalasc from a Methanol-utilizing Yeast,Candida sp. N-16

Defatted soybean extract was fractionated into protein fractions and low molecular weight fractions with gel filtration. NAD-dependent aldehyde dehydrogenase from bovine liver mitochondria and from yeast was found to oxidize aldehyde in both fractions. These enzymes, therefore, were used to determine the quantity of aldehyde. When the protein fraction obtained by gel filtration was subjected to gel filtration again, aldehyde was recovered in the protein fractions. The level of aldehyde in the protein fractions was unchanged before and after digestion of the protein with pepsin. When the soybean extract was incubated beforehand with aldehyde dehydrogenase and NAD⁺ and the subjected to gel filtration, no aldehyde was detected in the protein fractions. These results indicate that aldehyde dehydrogenase acts on the soybean protein-bound aldehyde. Alcohol dehydrogenase from horse liver in the presence of NADH did not convert the bound aldehyde to alcohol.

A large portion of the aldehyde in the extract was separated from the protein by acid precipitation of the protein. Aldehyde dehydrogenase acts on the aldehyde remaining in the protein after acid precipitation. Thus acid precipitation helps to save NAD⁺ required for complete removal of aldehyde from the soybean protein by aldehyde dehydrogenase.