现代生物工程分离提取技术在海洋生物资源开发上的应用

本文综述了在海洋资源开发上应用的现代生物工程分离技术。介绍了最新的分离提取技术如制备型和生产型色谱技术、超临界萃取技术、膜分离技术、毛细管电泳技术、酶工程技术等。从海洋生物资源中提取有用的生物活性物质,需要符合特定要求的现代生物工程技术。其中柱层析技术和超临界萃取技术是海洋生物活性物质分离提取技术中的主要部分。     

生物质谱技术与蛋白质组学

生物质谱技术是蛋白质组学的支撑技术.详细论述了质谱技术的分类与基本分析原理,重点论述了质谱技术的发展变化,包括基质辅助激光解吸飞行时间质谱技术,电喷雾质谱技术,MALDI-Q-TOF和MAL-DI-TOF-TOF等质谱技术,以及质谱技术在蛋白质组学研究中的应用与未来的发展和挑战.     

基因编辑技术的发展与挑战

基因编辑技术是人为的对基因片段进行修改的一种技术。新型基因编辑技术关注在人工核酸酶剪切技术领域,主要为ZFN技术,TALEN技术,CRISPR技术以及单碱基编辑技术。基因编辑技术的不断完善促进了农业,畜牧业和生物医学等领域的快速发展,但与此同时,技术缺陷和伦理争议也为其自身的发展带来了巨大的挑战。本文将对基因编辑技术的发展与挑战,以及国内外的伦理探讨进行简要综述,期望能启发读者重新认识基因编辑技术。     

鼻咽癌的放射治疗技术探究

目的:通过比较鼻咽癌放射治疗的不同技术方法,了解其优势及不同点,以期找到更有效并切合实际的技术方法,提高鼻咽癌的放疗技术水平。方法:常规外照射技术;等中心整体挡铅技术;三维适形放射治疗技术。结果:三种技术方法各具优缺点,结论:三维适形放射治疗技术最具优势,但设备和技术要求高;常规外照射技术经济实用,技术稳定性较差;等中心整体挡铅技术质量稳定。     

RNA研究相关技术及其应用

RNA技术可以分为RNA基础研究相关的技术、RNA应用相关的技术和RNA的生物信息学技术。RNA基础研究相关技术包括RNA分离纯化和鉴定技术、RNA与其他生物大分子相互作用技术、RNA高级结构的研究技术和其他相关RNA技术;RNA应用相关技术则包括用于生产其他产品的RNA技术和直接用于药物开发的RNA技术;RNA的生物信息学技术则有各种数据库、非编码RNA的预测、RNA二级结构预测和各种设计软件。本文简略介绍了上述各类RNA技术的原理及其国内外研究进展,从而有助于对RNA领域有关技术方面有一较全面的了解。     

微藻无菌化技术的研究进展

无菌纯藻是深入开展藻类生理学和遗传学研究的基础。目前已有涂布划线法,离心洗涤技术、稀释滤过技术、辐照技术、毛细吸管技术、抗生素技术、化学消毒技术、利用其他生理特性等技术用于微藻的纯化。拟介绍国内外近年来微藻无菌纯化技术的研究进展。     

呼吸道病毒多病原检测技术研究进展

呼吸道病毒感染是导致人群发病和死亡的主要原因之一。通过多重病原检测迅速筛查大量致病原,已成为呼吸道病毒感染检测的重要技术。本文介绍了呼吸道病毒多病原检测技术及一些对呼吸道病毒检测有潜在应用价值的新兴技术。这些技术包括多重呼吸道病毒快速分离培养技术、传统多重逆转录PCR技术、多重实时定量PCR技术、微芯片技术、质谱技术及宏基因组技术等。这些技术的发展和应用,不但有助于提高呼吸道病毒感染的快速诊断和治疗,而且也将促进新型呼吸道病毒的发现。     

膨化技术及其在食品工业中的应用

膨化技术作为一种新型食品生产技术,正逐步在食品工业中得到广泛的应用。本文就现在国内常用的油炸膨化技术、挤压膨化技术、微波膨化技术、低温气流膨化技术和CO2膨化技术予以阐述。     

工业生物催化技术在绿色精细化学品合成中的机遇

生物催化技术具有反应条件温和、专一性强、环境友好等特点,是传统化学方法无法比拟的。本文从生物催化技术的特点及其在精细化学品合成中的应用现状出发,从产品战略、技术策略等方面提出生物催化技术应用的方向与目标：生物催化与有机合成技术的集成、交叉将会是未来生物催化技术发展的重要方向;有机合成技术为生物催化技术的发展、应用指明并提供了更多技术、产品及产业机会。     

初级农产品质量安全检测技术研究进展

综述了初级农产品质量安全检测技术研究进展,包括样品前处理检测技术、仪器检测技术、确证检测技术和快速检测技术。样品前处理检测技术中的免疫亲和净化小柱在生物毒素检测中被广泛使用;确证检测技术中色谱—质谱连用技术因定性定量准确,在有条件的实验室中得到了快速发展;快速检测技术中酶抑制法简便、快速等优点使这项技术与大型仪器互补,在农药残留检测中被大力推广。     

The effects of artificial enrichment upon the planktonic and benthic communities in a mesotrophic to hypertrophic loch series in lowland Scotland

Phytoplankton, submerged macrophytes, zoobenthos and zooplankton communities were studied concurrently in three lochs which progressively increased in trophic state. The phytoplankton showed a change in dominance from Bacillariophyceae (Pennales) and Desmidaceae in the mesotrophic Loch of the Lowes to Bacillariophyceae (Pennales) and Cyanobacteria in eutrophic Balgavies Loch and to Bacillariophyceae (Centrales) and Chlorophyceae in hypertrophic Forfar Loch. The Nygaard Compound phytoplankton quotient rose from 1.2 in the Lowes to 12 in Forfar. There was a decrease in number of species of submerged macrophytes, and in depth of colonisation from 5 m in the Lowes to 2 m in Forfar which was proportional to the decrease in mean transparency. Macrophyte biomass, however, increased in proportion to the concentration of total phosphorus in the lochs. There was a decrease in species of littoral zoobenthos, but an increase in density of profundal benthos from the Lowes to Forfar. Zooplankton also showed an increase in density with enrichment, accompanied by changes in dominance. Calanoida were dominant in the Lowes; Cladocera in Balgavies and Cyclopoda in Forfar. The importance of these differences in understanding the effects of progressive enrichment and to the management of the lochs is discussed.     

Ornithine cycle in Nostoc PCC 73102. Arginase,OCT and arginine deiminase,and the effects of addition of external arginine,ornithine, or citrulline

Arginase, ornithine carbamoyl transferase (OCT) and arginine deiminase activities were found in cell-free extracts of Nostoc PCC 73102, a free-living cyanobacterium originally isolated from the cycad Macrozamia. Addition of either arginine, ornithine or citrulline to the growth medium induced significant changes in their in vitro activities. Moreover, growth in darkness, compared to in light, induced higher in vitro activities. The in vitro activities of arginase and arginine deiminase, two catabolic enzymes primarily involved in the breakdown of arginine, increased substantially by a combination of growth in darkness and addition of either arginine, or ornithine, to the growth medium. The most significant effects on the in vitro OCT activities where observed in cells grown with the addition of ornithine. Cells grown in darkness exhibited about 6% of the in vivo nitrogenase activity observed in cells grown in light. However, addition of external carbon (glucose and fructose) to cells grown in darkness resulted in in vivo nitrogenase activity levels similar to, or even higher than, cells grown in light. Growth with high in vivo nitrogenase activity or in darkness with the addition of external carbon, resulted in repressed levels of in vitro arginase and arginine deiminase activities. It is suggested that nitrogen starvation induces a mobilization of the stored nitrogen, internal release of the amino compound arginine, and an induction of two catabolic enzymes arginase and arginine deiminase. A similar and even more pronunced induction can be observed by addition of external arginine to the growth medium.     

Seasonal changes in intra- and interorgan occurrence of rodlet cells in freshwater bream

Significant seasonal differences in intra- and interorgan prevalence, abundance and distribution of rodlet cells (RC) were observed in freshwater bream caught in May and August 1997 from a PCB-polluted lake, Lake Kernaala, Finland. In May, the majority of RCs in liver were seen in blood vessel endothelium, while in August most cells were located in the epithelium of the intrahepatic biliary ducts. In kidney, a significant increase in RCs in the columnar epithelium of the collecting ducts was observed from May to August. RCs in spleen were extremely rare in May, but were seen frequently in the endothelium of the splenic blood vessels in August. In gill and intestine, RCs were found in every tissue sample studied, with no statistical differences in their abundance or distribution between seasons. No RCs were seen in gonads. Total numbers of RCs increased dramatically from May to August in kidney and in spleen. The frequency of RCs corresponded strongly with the current phase of parasitic infections in liver, kidney, and spleen. It is concluded that RCs play a role in host defence mechanisms in fish, displaying induced expression at the times of peak parasitic prevalences.     

小麦叶内硝酸还原的代谢库

随营养液中No_3~-浓度升高,叶片内No_3~-总量、代谢库大小(NIPS)及硝酸还原酶(NR)活性均升高,其中MPS与NK活性呈同步变化;No_3~-浓度达2.0mmol/L时,两者趋于稳值;若再增加NO_3~-浓度,则被吸收的NO_3~-积累于液泡中,而代谢库中NO_3~-含量(MPS)与NO_3~-总量之比有一定程度降低。低氮(NO_3~-浓度为1.0 mmol/L)情况下,反应液中无NO_3~-时,叶片内NR活性品种间有差异,但在50 mmol/L NO_3~-反应液中则品种间无差异;NK活性高的品种鲁麦8号及品种321叶内有大的NO_3~-代谢库,反应液中NO_3~-对NR活性刺激程度低,代谢库NO_3~-含量与叶NO_3~-总量之比高,而叶组织长时间反应过程中其NR活性衰减速率低。     

Histological comparison between wheat embryos developing in vitro from isolated zygotes and those developing in vivo

There is currently great interest shown in understanding the process of embryogenesis and, due to the relative inaccessibility of these structures in planta, extended studies are carried out in various in vitro systems. The culture of isolated zygotes in particular provides an excellent platform to study the process of in planta embryogenesis. However, very few comparisons have been made between zygotic embryos grown entirely in cultures and those grown in vivo. The present study analyses the differences and similarities between the in vitro and in vivo development of wheat zygotic embryos at the level of morphology and histology. The study was possible thanks to an efficient culture system and an appropriate method of preparing isolated wheat zygotes for microscopy. The in vitro embryos were fixed, embedded and sectioned in the two-celled, globular, club-shaped and fully differentiated stages. Embryos developing in vitro closely followed the morphology of their in planta counterparts and their cell types and tissues were also similar, demonstrating the applicability of the present culture system for studying the process of zygotic embryogenesis. However, some important differences were also detected in the case of in vitro development: the disturbance of or lack of initial polarity led to changes in the division symmetry of the zygotes and subsequently to the formation of uniform cells in the globular structures. Presumably, differences between the in vitro and in planta environments resulted in a lower level of differentiation and maturation in in vitro embryos and in abundant starch and protein accumulation in the scutellum.     

Pharmacokinetics of the enantiomers of trans-tramadol and its active metabolite, trans-O-demethyltramadol, in healthy male and female chinese volunteers

By using a high-performance capillary electrophoresis method, the pharmacokinetics of the enantiomers of trans-tramadol (trans-T) and its active metabolite, trans-O-demethyltramadol (M1), was studied in healthy male and female Chinese volunteers after oral administration of 100 mg trans-T hydrochloride. The values of Cmax for the enantiomers of trans-T and M1, and AUC0- infinity for (-)-trans T, (+)-M1, and (-)-M1 were higher in females than in males. The values of V(d)/F for the enantiomers of trans-T and CLr for (+)-M1 were lower in females than in males. The value of t(1/2) for (-)-M1 was longer in females than in males. There were significant differences in pharmacokinetic parameters of the two enantiomers of trans-T or M1 both in males and in females. The (+)/(-)-enantiomeric ratios of t(max), V(d)/F for trans-T in males were significantly different from those in females and the (+)/(-)-enantiomeric ratios of pharmacokinetic parameters for M1 in males were similar to those in females. There are gender-related differences in the pharmacokinetics of the enantiomers of trans-T and M1 which may be due to the greater body weights for men and/or the higher CYP2D6 activity in women. The pharmacokinetics of trans-T and M1 is stereoselective in men and women. There is a gender-related difference in the stereoselectivity in pharmacokinetics of trans-T in human and the stereoselectivity in pharmacokinetics of M1 in men is similar to that in women. Chirality 16:112-118, 2004.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Hypothalamic metabolism of neurotransmitters (serotonin,norepinephrine, dopamine) and NPY,and gonadal and adrenal activities,during the early postnatal period in the rat

It is noteworthy that in the rat the early postnatal life is marked by an activation of both the corticostimulating function of the adenohypophysis in neonates of both sexes and of the gonadostimulating function mainly in males. In order to specify if such neuroendocrine variations are temporally correlated with changes in the hypothalamic metabolism of neurotransmitters, the hypothalamic metabolism of serotonin (5 HT), norepinephrine (NE), and dopamine (DA) and the hypothalamic content of neuropeptide Y (NPY) have been investigated in newborn rats of both sexes, delivered at term by cesarean section, as well as changes in the activity of both the hypothalamo-pituitary adrenal axis (HPA) and the hypothalamo-pituitary gonadal axis (HPG). Experimental data suggested that 1) in males a rise in hypothalamic metabolism of 5 HT, NE and DA occurs during the first two hours after delivery, whereas in females, only the metabolism of NE increases. Moreover, the postnatal metabolism of NE was higher in females than in littermate males; 2) NPY content of the hypothalamus, which was at birth significantly higher in males than in females, dropped in the former but not in the latter; 3) in newborn males, an early surge of plasma testosterone occurs, suggesting postnatal activation of the HPG axis; on the other hand, in females, a late and slight increase in plasma estradiol is observed; 4) in early postnatal life, a sex-independent rise in plasma ACTH and adrenal and plasma corticosterone levels suggest a comparable activation of the HPA axis in newborns of both sexes. In conclusion, the early postnatal activation of the corticostimulating function in neonates of both sexes and that of the gonadostimulating function, mainly in males, could be temporally correlated with a rise in the hypothalamic metabolism of two neurotransmitters, 5 HT and NE, and of NPY content. According to our data, a sex-dependent metabolsim of neurotransmitters in the hypothalamus is already apparent in early postnatal life.     

CARBOHYDRASES IN THE DIGESTIVE SYSTEM OF THE SPINED SOLDIER BUG,Podisus maculiventris (SAY) (HEMIPTERA: PENTATOMIDAE)

The spined soldier bug, Podisus maculiventris, is a generalist predator of insects and has been used in biological control. However, information on the digestion of food in this insect is lacking. Therefore, we have studied the digestive system in P. maculiventris, and further characterized carbohydrases in the digestive tract. The midgut of all developmental stages was composed of anterior, median, and posterior regions. The volumes of the anterior midgut decreased and the median midgut increased in older instars and adults, suggesting a more important role of the median midgut in food digestion. However, carbohydrase activities were predominant in the anterior midgut. In comparing the specific activity of carbohydrases, α‐amylase activity was more in the salivary glands (with two distinct activity bands in zymograms), and glucosidase and galactosidase activities were more in the midgut. Salivary α‐amylases were detected in the prey hemolymph, demonstrating the role of these enzymes in extra‐oral digestion. However, the catalytic efficiency of midgut α‐amylase activity was approximately twofold more than that of the salivary gland enzymes, and was more efficient in digesting soluble starch than glycogen. Midgut α‐amylases were developmentally regulated, as one isoform was found in first instar compared to three isoforms in fifth instar nymphs. Starvation significantly affected carbohydrase activities in the midgut, and acarbose inhibited α‐amylases from both the salivary glands and midgut in vitro and in vivo. The structural diversity and developmental regulation of carbohydrases in the digestive system of P. maculiventris demonstrate the importance of these enzymes in extra‐oral and intra‐tract digestion, and may explain the capability of the hemipteran to utilize diverse food sources.