俄罗斯堪察加地区热泉及其周边生境的泉古菌多样性

【目的】泉古菌为陆地热泉系统的主要古菌类群,可能在自然界生源元素的地球化学循环中发挥着重要作用。本研究旨在揭示俄罗斯堪察加地区热泉以及热泉周边区域的泉古菌多样性,同时基于之前已获得的我国云南地区热泉数据,比较两地区泉古菌群落差异。【方法】通过构建16S rRNA基因片段克隆文库获得序列信息和丰度,随后进行物种多样性、系统发育和群落结构差异分析。【结果】高温热泉Burlyashi Liza(BSL,89℃)中的泉古菌全部属于热变形菌纲(Thermoprotei)内的物种。中温热泉TF Vent 2(TFV,49℃)的群落结构主要由不确定的热变形菌纲类群、不确定的泉古菌类群、高温水环境泉古菌类群Ⅱ(HWCG-Ⅱ)和奇古菌下的Group1.1b类群组成。热泉周边常温环境的主要物种与热泉环境的代表性克隆pJP41一起聚成一个较大的遗传分枝。Jackknife聚类树和主坐标分析(Principal coordinates analysis,PCoA)的结果显示:温度相似的样点,其泉古菌群落结构相对来说更为相似。【结论】俄罗斯堪察加地区与我国云南地区热泉中的泉古菌存在着一定程度上的不同。陆地热泉系统影响着其周边环境的泉古菌类群。热泉中泉古菌群落结构受温度的明显影响。     

Mortality in women in relation to their childbearing history.

With data from the Office of Population Censuses and Surveys'' longitudinal study the mortality of currently married women aged under 60 in 1971 was investigated in relation to the number of liveborn children reported at the 1971 census, adjusting for their husbands'' social class. Women who had never had children experienced a higher mortality from many causes of death than the parous women, and this was probably due, at least in part, to selective factors. When the analysis was confined to parous women mortality from diabetes mellitus and cervical cancer increased significantly and oesophageal cancer decreased significantly with increasing number of liveborn children. Mortality from all circulatory diseases and from hypertensive disease, ischaemic heart disease, and subarachnoid haemorrhage tended to rise with parity, though the trends were not statistically significant. Mortality from breast cancer decreased significantly with the number of liveborn children, but only when nullipara were included in the analyses. These data suggest that there may be residual and cumulative effects of childbearing which influence patterns of disease in the long term.     

Myelodysplastic syndromes: their history, evolution and relation to acute myeloid leukaemia

The myelodysplastic syndromes (MDS) constitute a heterogeneous group of clonal disorders arising from a multipotent haemopoietic progenitor which share a leukaemic propensity, 30% of cases culminating in acute myeloid leukaemia (AML). Their pathogenesis probably entails multiple steps, phenotypic progression being determined by either expansion or evolution of the abnormal clone. The clonal origin of certain cases of de novo AML is analogous to that of MDS and evidence that they share a common pathogenesis and distinct biological characteristics is beginning to emerge.     

高通量测序分析云南腾冲热海热泉真菌多样性

【目的】本研究揭示云南腾冲热海热泉真菌多样性及群落分布格局,探讨其理化因子对真菌群落结构的影响。【方法】利用Illumina Hi Seq2500高通量测序平台对腾冲热海热泉沉积物宏基因组ITS基因进行测序,并进行生物信息分析。【结果】从5个热泉样品中共检测到343484条有效序列,包括5个真菌门,20个纲,66个目。右姐妹泉(JMQR)、左姐妹泉(JMQL)、蛤蟆嘴泉(M)、桥泉(QQ)及鼓明泉(GMQP)分别以Agaricales、Eurotiales、Capnodiales和Hypocreales等为优势目。在属水平上,共获得365个属,从JMQR中检测到212个属,以裂褶菌属(Schizophyllum)为最优势;从JMQL中挖掘到197个属,以青霉属(Penicillium)为最优势类群;从M和QQ中分别获得222个和270个属,均以枝孢属(Cladosporium)为最优势;从GMQP中发现179个属,以侧齿霉属(Engyodontium)丰度最高。NH4+含量、温度及pH影响不同优势真菌的分布,其中以pH与优势类群(OTU1%)结构变化显著性最高(P=0.05)。【结论】云南腾冲热海高温热泉蕴藏着极其丰富的真菌物种,其不同样品真菌分布具有差异性,pH可能是影响热泉真菌群落分布的重要因素之一。     

Life in hot springs and hydrothermal vents

Hot springs and hydrothermal systems occurring within volcanic areas are inhabited by hyperthermophilic microorganisms, some of which grow at temperatures up to 110 °C. Hyperthermophiles grow anaerobically or aerobically by diverse metabolic types. Within the high temperature ecocystems, primary production is independent from solar energy.Presented at the Session Water in the Solar System and Its Role in Exobiology during the 26th General Assembly of the European Geophysical Society, 22–26 april 1991 in Wiesbaden, Germany.     

Intertubular cells and their relation to the renal cambium]

The intertubular cells (ITC) of the cortex of the human kidney (from the fetus, newborns, children aged from 1 to 5 years, adults aged from 30 to 70) were studied. The ITC in the kidneys with an undeveloped structure (fetus, newborns) amounted 21.4--12.6% of the epithelial cells of the convoluted tubules and for children over one year and adults--7.6%. When the kidney was affected by nephrotoxic poison (ethylene-glycol) and deep hypoxia and ITC were activated, began to multiply and made up 14.5% of the epithelium of the convoluted tubules. It is suggested that the ITC represented a peculiar cambium of the renal tubules which formed due to the transferring of a part of the cells of the metaneophrogenic tissue into position of rest (R-period).     

Heat stable lipase activity of thermotolerant bacteria from hot springs at Orissa, India

Thermotolerant bacteria (35 in toto) isolated from three hot springs (Atri, Taptapani and Deuljhari, Orissa), were screened for lipase activities. Of these, nine strains of Bacillus spp. and three strains of Pseudomonas spp. showed heat stable lipase activity at 60 degrees C. The hydrolytic activity of these bacteria was tested using Tween-20 and Tween-80 as substrates at different temperatures using plate assay and titration techniques. The hydrolytic activity at different pH values and salt concentrations was investigated.     

Archaeal and bacterial diversity in hot springs on the Tibetan Plateau, China

The diversity of archaea and bacteria was investigated in ten hot springs (elevation >4600 m above sea level) in Central and Central-Eastern Tibet using 16S rRNA gene phylogenetic analysis. The temperature and pH of these hot springs were 26-81°C and close to neutral, respectively. A total of 959 (415 and 544 for bacteria and archaea, respectively) clone sequences were obtained. Phylogenetic analysis showed that bacteria were more diverse than archaea and that these clone sequences were classified into 82 bacterial and 41 archaeal operational taxonomic units (OTUs), respectively. The retrieved bacterial clones were mainly affiliated with four known groups (i.e., Firmicutes, Proteobacteria, Cyanobacteria, Chloroflexi), which were similar to those in other neutral-pH hot springs at low elevations. In contrast, most of the archaeal clones from the Tibetan hot springs were affiliated with Thaumarchaeota, a newly proposed archaeal phylum. The dominance of Thaumarchaeota in the archaeal community of the Tibetan hot springs appears to be unique, although the exact reasons are not yet known. Statistical analysis showed that diversity indices of both archaea and bacteria were not statistically correlated with temperature, which is consistent with previous studies.     

Bacterial and archaeal diversities in Yunnan and Tibetan hot springs,China

Thousands of hot springs are located in the north‐eastern part of the Yunnan–Tibet geothermal zone, which is one of the most active geothermal areas in the world. However, a comprehensive and detailed understanding of microbial diversity in these hot springs is still lacking. In this study, bacterial and archaeal diversities were investigated in 16 hot springs (pH 3.2–8.6; temperature 47–96°C) in Yunnan Province and Tibet, China by using a barcoded 16S rRNA gene‐pyrosequencing approach. Aquificae, Proteobacteria, Firmicutes, Deinococcus‐Thermus and Bacteroidetes comprised the large portion of the bacterial communities in acidic hot springs. Non‐acidic hot springs harboured more and variable bacterial phyla than acidic springs. Desulfurococcales and unclassified Crenarchaeota were the dominated groups in archaeal populations from most of the non‐acidic hot springs; whereas, the archaeal community structure in acidic hot springs was simpler and characterized by Sulfolobales and Thermoplasmata. The phylogenetic analyses showed that Aquificae and Crenarchaeota were predominant in the investigated springs and possessed many phylogenetic lineages that have never been detected in other hot springs in the world. Thus findings from this study significantly improve our understanding of microbial diversity in terrestrial hot springs.     

Fe-Si biominerals in the Vilyuchinskie hot springs, Kamchatka Peninsula, Russia.

The micromorphological structure of microbial mats (biomats) from the hot springs of the Vilyuchinskaya hydrothermal system, Kamchatka Peninsula, Russia, were investigated. The Vilyuchinskie hot springs had a discharge temperature of 55-56 degrees C and Na-Ca-HCO3-type waters rich in silicic and boric acids. Water and biomats had high concentrations of Fe, Mn, Sr, and As. Enumeration of total bacterial abundance (TBA) demonstrated a low density of bacterial populations. However, the fractions of metabolically active bacteria and respiring iron-oxidizing bacteria in the hot-spring water were high, comprising 68 and 21% of TBA, respectively. Scanning electron microscopy equipped with an energy dispersive X-ray spectrometer (SEM-EDX) showed that unicellular rod-shaped bacteria about 5-microm long predominated in the brown biomats. The mineral capsules of these bacteria contained large amounts of Fe and Si. Extracellular and intracellular particles were observed by transmission electron microscopy. Fe-oxidizing bacteria were isolated from the biomats on agar plates with selective medium. Therefore, it can be concluded that microorganisms inhabiting the biomats of the Vilyuchinskie hot springs are essential for the deposition of Fe-minerals at neutral pH.     

Light-induced absorption changes at 590 nm in isolated pea chloroplasts and their relation to plastocyanin]

The light-induced decrease in absorption with the minimum at 590-595 nm has been found in chloroplasts of etiolated pea seedlings by the method of dual-wavelength difference spectrophotometry. It has been shown that this effect is caused by photoreduction of the electron carrier with the absorption maximum of its oxidized form at 590 nm. Photoreduction of the carrier has been observed after excitation both by the short-wave (646 nm) and long-wave (709 nm) red light, although the latter is less effective. It has been suggested that the absorption changes at 590 nm are caused by light-induced redox conversions of plastocyanin bound to chloroplast membrane.     

Diversity of Crenarchaeota in terrestrial hot springs in Tengchong, China

Diversity of Crenarchaeota was investigated in eight terrestrial hot springs (pH 2.8–7.7; temperature 44–96°C) located in Tengchong, China, using 16S rRNA gene phylogenetic analysis. A total of 826 crenarchaeotal clones were sequenced and a total of 47 operational taxonomic units (OTUs) were identified. Most (93%) of the identified OTUs were closely related (89–99%) to those retrieved from hot springs and other thermal environments. Our data showed that temperature may predominate over pH in affecting crenarchaeotal diversity in Tengchong hot springs. Crenarchaeotal diversity in moderate-temperature (59–77°C) hot springs was the highest, indicating that the moderately hot-temperature springs may provide optimal conditions for speciation of Crenarchaeota.     

Meiofauna of springs in Finland in relation to environmental factors

The meiofauna was studied from springs in Finland which wascompletely ice-covered during the last glacial epoch. Of the31springs that were examined, 15 were in areas considered to bein anatural state and 16 had catchment areas subject toanthropogenicdisturbance from one of four sources: agriculture,inhabitation,gravel extraction or winter road de-icing with NaCl. The taxarecorded were a mixture of those already described fromepigeicwaters or groundwaters and some which may be regarded ascharacteristic of springs Statistical analysis revealeddifferencesin the meiofaunal taxa in relation to the water quality orcatchment area variables. Of the major meiofaunal groups thenematodes favoured springs influenced by agriculture,oligochaeteswere most tolerant of road de-icing, cladocerans and copepodspreferred springs in a natural state, ostracods couldwithstand theinfluence of road de-icing and gravel extraction, whilstdipteranlarvae could withstand the influence of agriculture.Oligochaetescomprised 13.4% of meiofaunal numbers. The most abundantspecieswas Aeolosoma quaternarium, which was most numerous insprings in a natural state, while Dero digitatapreferredeutrophic conditions. Harpacticoids comprised 14.1% ofindividualsand clearly preferred a natural state, Bryocamptusechinatusand Moraria brevipes being the most abundant species.Ostracods, of which the most abundant species was Potamocyprispallida, were the most numerous animal group, constituting21% ofthe meiofaunal population, and their numbers were greatest insprings influenced by road de-icing or gravel extraction.Dipteranlarvae, of which the majority were chironomids, comprised14.9% ofindividuals. The ostracods Potamocypris pallida andthreespecies of Candona and the harpacticoid Bryocamptuscuspidatus are new records for Finland.     

Association of bacteria and yeasts in hot springs.

The thermophilic bacterium Bacillus sp. strain TB-1 was isolated in association with the yeast Debaryomyces vanriji from hot springs at 46 degrees C. It was shown that TB-1 excreted thiamine into the culture broth, which not only promoted D. vanriji growth in mixed culture but also increased the maximal temperature for yeast growth.     

河北承德地区两个温泉中细菌的多样性分析

通过构建16S rDNA克隆文库,对承德地区两温泉中的细菌多样性水平及系统发育关系进行了初步研究。研究表明:68°C的A11文库中阳性克隆的16S rDNA序列分属5个细菌类群,分别为Firmicutes(6.25%)、Deinococcus-Thermus(25.0%)、Gammaproteobacteria(12.5%)、Betaproteobacteria(50.0%)、Alphaproteobacteria(6.25%);而74.5°C的A12文库仅属于一个细菌类群:厚壁菌门(Firmicutes)。两温泉中细菌多样性的差异表明,温度是影响温泉中细菌多样性水平的重要因素。此外,A11文库中克隆的16S rDNA序列与许多已知的可产色素的好氧菌相似性很高,而A12文库中的细菌多数为专性厌氧或兼性厌氧型,其中厌氧芽孢杆菌属(Anoxybacillus)中的Anoxybacillus flavithermus可以作为研究泉华形成的理想材料。     

Isozyme variation in roe deer in relation to their population history in Britain

The level of genetic variation in 245 roe deer (Cupreolus cupreolus L.), taken from 15 populations across Britain, was estimated by investigating electrophoretic polymorphism at 15 enzyme loci. The proportion of polymorphic loci and the average heterozygosity of roe deer in Britain were estimated as 13.3% and 3.2%, respectively. Allele frequencies at one locus suggested the existence of an east-west cline of an allelic variant in southern Britain which may have originated from an introduction of roe from continental Europe in the last century. These results are discussed in relation to the theoretical expectations for this species and the documented historical background of roe deer inBritain.     

海南海口温泉真菌、细菌多样性及其环境影响因素分析

【目的】海南海口含有丰富的温泉资源,对温泉微生物多样性进行研究,有助于进一步开发和利用海南温泉微生物资源。【方法】本文采用Illumina Hi Seq高通量测序技术对海口3个温泉[海甸岛荣域温泉(S1)、火山口开心农场温泉(S2)和西海岸海长流温泉(S3)]水样中微生物ITS序列和16Sr RNA基因V3-V4区进行测序及生物信息学分析,探究海口市3个不同区域的温泉真菌多样性与细菌多样性。【结果】(1)α多样性分析表明,真菌群落中,S3(29)S1(29)S2,而在细菌群落中,S2(29)S1(29)S3。β多样性分析表明,3个温泉真菌群落和细菌群落组成差异皆显著。(2)分类分析表明,温泉真菌群落优势菌门为子囊菌门(Ascomycota)和担子菌门(Basidiomycota),细菌群落优势菌门为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、Thermi、硝化螺旋菌门(Nitrospirae)、绿菌门(Chlorobi)、厚壁菌门(Firmicutes)、绿弯菌门(Chloroflexi)、放线菌门(Actinobacteria)。(3) CCA (Canonical correspondence analysis)分析表明,3个温泉的真菌群落主要影响因子是温度,细菌群落主要影响因子是总磷。【结论】海南省海口市温泉中含有丰富的微生物资源,其微生物群落组成受多种环境因子影响,且影响真菌和细菌的主要环境因子不同。