用乙脑病毒减毒株单克隆抗体分析乙脑病毒强毒株和减毒株的抗原差别

用乙型脑炎(乙脑)病毒强毒株免疫制备的单克隆抗体(McAb)分析证明强毒株之间的抗原差别,已有研究报道。本实验用乙脑病毒减毒活疫苗2-8株免疫制备的McAb分析强毒株和减毒株之间的抗原差别。 一、乙脑病毒株 2-8株和5-3株均为减毒活疫苗株。SA14株和A2株均为强毒株,SA14株是2-8株和5-3株的母株,A2株是国内实验室标准株。     

杜仲内生菌的分离及产PDG菌株的筛选

从树龄达7a以上杜仲皮中分离得到122株内生菌,其中真菌75株,细菌47株,经摇瓶培养后分析各菌株产松脂醇二葡萄糖苷(PDG)的能力,结果发现有8株菌能产生PDG,最高产量可达13.387 mg/L。经初步鉴定,这8株菌分属于5属,即茎点菌属(Phloma)、腐霉属(Pythium)、卵形孢霉属(Oospora)、球黑粉霉属(Tolypospori-um)、砖红镰孢霉属(Lateritium)。     

8-Mop选育薰衣草链霉菌(Streptomyces lavendulae)的研究

本文首次报导8-甲氧基补骨脂素(8-Mop)单一选育薰衣草链霉菌(Streptomyoes lavendulae)的研究结果,曾有摇瓶发酵单位提高18．3％的高产株获得,高产株已在国内应用。     

拟柱孢藻N8全基因组测序及磷吸收转运通路的比较分析

为从分子水平解析热带特征性蓝藻-拉氏拟柱孢藻(Cylindrospermopsis raciborskii,简称拟柱孢藻)环境适应机制,研究以广东省镇海水库中分离的拟柱孢藻藻株N8为材料,采用PacBio单分子实时测序技术(Single Molecule Real-Time, SMRT)进行测序,并初步进行全基因组特征的比较分析。结果显示拟柱孢藻N8全基因组大小为3.857 Mb, GC含量为40.13%,预测编码基因个数为3598个,在COG、KEGG和GO数据库中注释到的基因数分别为2429、1664和2244个。N8藻株与美国国立生物技术信息中心(NCBI)上公布的27株拟柱孢藻基因组大小和GC含量基本一致,但N8的编码基因数最多。基于拟柱孢藻全基因组单拷贝基因的系统进化树表明N8藻株与韩国藻株GIHE 2018的亲缘关系最近。N8藻株的基因组中未发现拟柱孢藻毒素(CYN)和石房蛤毒素(STX)合成酶基因簇,表明该藻株不产蓝藻毒素CYN和STX。对N8藻株和其他7藻株的磷吸收转运通路比较分析表明,这些藻株均拥有较为完整的磷吸收转运基因(双组分调节系统、低亲和力无机磷转运基因、高亲...     

粟长孺孢菌的异核现象

本文报道了粟长孺孢的菌(Hetminthosporium setariae)的异核现象。用γ-射线和甲基磺酸乙酯诱变获得的颜色、形态和营养突变株(H8、Hw)可在基本培养基上形成异核体(8W)。其以上各种特性不同于亲本。 8W分离之后的突变株可稳定地传代,混合后仍能形成异核体。从而证实了该菌的异核性。观察并测定了亲本株和异核体的生长率、致病性及产孢能力。粟长孺孢菌(H8)和玉蜀黍长孺孢菌(866·R-8)可形成种间异核体。     

滴水湖沉积物中可培养优势微生物种群初探

于滴水湖湖心采集底泥样品,对底泥中可培养优势菌种进行分离、纯化,并利用Biolog微生物自动分析系统进行鉴定。结果显示,滴水湖沉积物中菌落总数为2.43×104CFU/g,分离纯化后的8株优势菌种中,革兰氏阴性菌占87.5%,其中7株为GN-NENT(革兰氏阴性非肠道菌)、1株为GP-ROD SB(革兰氏阳性芽孢杆菌)。鉴定结果显示,8株菌种分别为:鳗鱼气单孢菌(Aeromonas encheleia)、乙酸钙不动杆菌/基因型1(Acinetobacter calcoaceticus/genospecies1)、舒氏气单胞菌(Aeromonas schubertiiDNA group12)、腐败希瓦氏菌B(Shewanella putrefaciens B)、维罗纳/温和气单胞菌(Aeromonas veronii/sobria DNA group8)、坎氏弧菌(Vibrio campbelli)、蕈状芽孢杆菌(Bacillus mycoides)和梅氏弧菌(Vibrio metschnikovii)。     

用标记分析法对我国海南地区登革2型病毒株的抗原表位分析

用标记分析(signature analvsis)法了解我国海南地区3年(1985—1987)来流行的登革2型(DEN-2)病毒株的抗原性变化。用3种单克隆抗体(McAb),包括黄病毒属特异、亚属特异和登革2型型特异,分析了8个DEN-2病毒流行株,并与标准株新几内亚B林进行比较．通过统计分析和微机处理,发现8株中有5株与株准株类似,有3株显示出明显差异。株记分析法为病毒抗原性分析提供了一个高度敏感的方法,并可用于监测一个地区病毒株群的变化及新株的引人。     

油樟内生真菌产油脂初步研究

采用GC-MS法分析78株油樟内生真菌(其中油樟根内生真菌43株,茎内生真菌11株,叶内生真菌24株)发酵产物,发现半数以上内生真菌能够产C_(16)到C_(19)的脂肪酸及相应的甲酯;利用索氏抽提法提取78株油樟内生真菌的总油脂并采用GC-MS法分析其组分,发现4株内生真菌(编号分别为YG48、YG64、YJ9、YY8)菌丝内油脂相对含量较高,种类较少,其中YG48、YY8几乎只产棕榈酸酯、亚油酸甲酯两种油脂,YG64、YJ9主要产油酸、硬脂酸、棕榈酸甲酯、油酸酰胺及硬脂酰胺。     

Q热立克次体中国株的16S-23SrDNA间区序列分析

用PCR扩增了 7株中国分离株 (七医、新桥、雅安、李、YS-8、YS-9和YH-11 )和2株国际参考株 (Henzerling和Grita)的 1 6S-23SrDNA基因间区 ,对扩增产物进行了序列分析。结果发现它们仅在少数几个碱基位上有不同。在第 6 0位上 3个云南分离株YS-8、YS-9、YH-11和Grita株与Stein等报道的序列 (包括九里、其它国际参考株和一些法国临床分离株 )的碱基序列一致 ,为“C” ;其他 5株为“A” ,此位点的不同可能与适应不同的地理环境相关。另外 ,YS-     

Assessing protein co-evolution in the context of the tree of life assists in the prediction of the interactome

The identification of the whole set of protein interactions taking place in an organism is one of the main tasks in genomics, proteomics and systems biology. One of the computational techniques used by many investigators for studying and predicting protein interactions is the comparison of evolutionary histories (phylogenetic trees), under the hypothesis that interacting proteins would be subject to a similar evolutionary pressure resulting in a similar topology of the corresponding trees. Here, we present a new approach to predict protein interactions from phylogenetic trees, which incorporates information on the overall evolutionary histories of the species (i.e. the canonical "tree of life") in order to correct by the expected background similarity due to the underlying speciation events. We test the new approach in the largest set of annotated interacting proteins for Escherichia coli. This assessment of co-evolution in the context of the tree of life leads to a highly significant improvement (P(N) by sign test approximately 10E-6) in predicting interaction partners with respect to the previous technique, which does not incorporate information on the overall speciation tree. For half of the proteins we found a real interactor among the 6.4% top scores, compared with the 16.5% by the previous method. We applied the new method to the whole E.coli proteome and propose functions for some hypothetical proteins based on their predicted interactors. The new approach allows us also to detect non-canonical evolutionary events, in particular horizontal gene transfers. We also show that taking into account these non-canonical evolutionary events when assessing the similarity between evolutionary trees improves the performance of the method predicting interactions.     

Isobolographic analysis of the dual-site synergism in the antinociceptive response of tramadol in the formalin test in rats

Tramadol is an atypical opioid with a complex mechanism of action including a synergistic interaction between the parent drug and an active metabolite. The local action of the parent drug is poorly documented. This study was designed to evaluate the site-site interaction of the antinociception produced by tramadol given by two different routes. The effects of individual and fixed-ratio combinations of intraplantar (i.pl.) and intraperitoneal (i.p.) tramadol were evaluated using the formalin test in rats. Isobolographic analysis was employed to identify the synergy produced by combinations. In both first and second phases of the formalin test, tramadol was active not only by the systemic (ED50 10.2+/-2.1 and 7.1+/-0.5 mg/kg i.p.) but also by the local route (ED50 171.0+/-44.8 and 134.6 microg/paw i.pl.). The isobolographic analysis revealed a "self-synergism" in the antinociceptive effect between the two routes of administration, as the experimental ED50 (211.1+/-13.6 and 45.9+/-3.9 "dose units" phase 1 and 2, respectively) of the combination was significantly lower than the theoretical ED50 (422.2+/-50.5 and 138.5+/-9.2 "dose units"). The mechanism underlying this self-synergism appears to be partially opioid since systemic but not local naloxone reversed the potentiation. The observed dual-site interaction in the antinociceptive action of tramadol provides insights for alternatives in the management of pain.     

Sexual differences in the interhemispheric asymmetry of the transcallosal responses of the associative areas in the cat neocortex

Sex differences of hemisphere asymmetry of homo- and heterotopic transcallosal responses in association cortex of 48 cats (24 male and 24 female) immobilized by tubocurarine have been studied by means of topographic EPs recordings in both hemispheres. In males left hemisphere dominates by the amplitude of homotopic and positive wave of heterotopic EPs and right hemisphere dominates by the amplitude of negative wave of heterotopic sensorimotor cortex EPs. The individual asymmetry of EPs has been observed in sensomotor cortex of females and in parietal cortex of animals of both sex. The interhemispheric asymmetry is expressed distinctly in females than in males. It is concluded that sex dimorphism is present in functional organization of associative system of (callosal and intracortical) connections in cat's neocortex projection and association areas which means its more expressed hemisphere lateralization in males with more expressed interhemispheric asymmetry of functional transcallosal connections in females.     

临汾市山区水保封禁治理对野生药用植物的恢复的研究

通过对临汾市山区水保封禁治理区域内药用植物的恢复研究,得出:连翘、翅果油树作为该区最主要的两种药用植物,经三年的封禁,其密度恢复分别增加183.8%、8.0%,产量增加9.8%、460.2%;其它药材增加密度为5.6%、产量255.0%,而对其它药用植物的研究可知,耐干旱的、阳性的药用植物恢复好于耐阴,阴性的药用植物,草本药用植物优于灌木、乔木,土石山区的药用植物恢复优于黄土区.封禁治理应是一个长期的植被恢复过程.     

Variability in the role of the gasbladder in fish audition

The teleost gasbladder is believed to aid in fish audition by transferring pressure components of incoming sound to the inner ears. This idea is primarily based on both anatomical observations of the mechanical connection between the gasbladder and the ear, followed by physiological experiments by various researchers. The gasbladder movement has been modeled mathematically as a pulsating bubble. This study is extending the previous work on fish with a physical coupling of the gasbladder and ear by investigating hearing in two species (the blue gourami Trichogaster trichopterus, and the oyster toadfish Opsanus tau) without a mechanical linkage. An otophysan specialist (the goldfish Carassius auratus) with mechanical coupling, is used as the control. Audiograms were obtained with acoustically evoked potentials (e.g., auditory brainstem response) from intact fish and from the same individuals with their gasbladders deflated. In blue gourami and oyster toadfish, removal of gas did not significantly change thresholds, and evoked potentials had similar waveforms. In goldfish thresholds increased by 33–55 dB (frequency dependent) after deflation, and major changes in evoked potentials were observed. These results suggest that the gasbladder may not serve an auditory enhancement function in teleost fishes that lack mechanical coupling between the gasbladder and the inner ear. Accepted: 28 February 2000     

Role of the temperature factor in determining the nature of the chronotropic response of the heart of cats in the simulation of increased venous inflow

The heart rate changes in response to the imitation of venous input to the heart by infusion of an additional blood volume to the right atria have been studied on anesthetized by chloralose cats. It has been discovered that patterns of the heart rate changes are determined by the infused blood temperature if it is equal to the blood temperature in heart, tachycardia appears, if it is below this temperature, bradycardia develops. These data explain, from our point of view, the contradictory results obtaining by different authors in experiments with the imitation of the increased venous input (Bainbridge reflex).     

Analysis of the process of learning in the formation of the conditioned reflex of avoidance in rats

During acquisition of avoidance conditioned reflex (CR) in shuttle box by electric shock it is shown that the performance of that defence reaction is induced by the joint action of two factors: general arousal of animals and motivation. Motor activity of rats in an "open field", the number of short-latency (2s) and intersignal responses during formation of the avoidance CR are in index of the general arousal of rats. An artificial increase in the general arousal of animals by caffeine induces acceleration of CR performance. A constant level of the general arousal of rats is one of the reasons that oxytocin does not influence the rate and dynamics of the avoidance CR performance in rats.     

Reserves of carbon in the organic matter of postfire pine forests in the southwest of the Baikal region

A change in the mass and composition of organic matter in the phytomass and soil of pine forests affected by mid-intensity and high-intensity fires is considered. It is shown that a mid-intensity fire did not catastrophically affect the pool of carbon in the middle-aged pine forests of the subtaiga forest-steppe and the taiga higher belt areas in the southwest of the Baikal region. Five years after a high-intensity fire, the carbon reserves in a mature taiga pine forest remain 20% lower than in an unaffected pine forest. Compared with the reference figures, the mass of C and soil cover in the stand phytomass decreased by 18 and 63%, respectively. In the easily mineralizable fraction of organic matter, the reserves of carbon decreased by half owing to burnout of waste wood (by 64%) and root detritus (by 50% compared with the reference tree stand figures).     

Role of the substantia nigra in the behavioural-cardiovascular integration in the cat

Electrical stimulation of the substantia nigra elicited complex patterns of response composed of somatomotor and circulatory changes. Increase in blood pressure associated with acceleration in heart rate was consistently produced by substantia nigra stimulation both in conscious and in anaesthetized cats. The respiration was either accelerated or arrested by the stimulation. Also self-stimulation of the substantia nigra elicited pressor responses. Electrical stimulation of the nucleus of the tractus solitarius paired with self-stimulation of the substantia nigra, produced regular changes in the lever-pressing rate for self-stimulation. It is suggested that the substantia nigra is probably involved in the neural mechanisms coupling the circulatory changes with the somatomotor responses.