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991.
García-Echauri SA Gidekel M Gutiérrez-Moraga A Santos L De León-Rodríguez A 《Folia microbiologica》2011,56(3):209-214
Culturable psychrophilic prokaryotes were obtained of samples of glacier sediment, seaside mud, glacier melted ice, and Deschampsia antarctica rhizosphere from Collins glacier, Antarctica. The taxonomic classification was done by a culture-dependent molecular approach
involving the Amplified Ribosomal DNA Restriction Analysis. Two hundred sixty colonies were successfully isolated and sub-cultivated
under laboratory conditions. The analysis showed a bacterial profile dominated by Beta-proteobacteria (35.2%) followed by
Gamma-proteobacteria (18.5%), Alpha-proteobacteria (16.6%), Gram-positive with high GC content (13%), Cytophaga–Flavobacterium–Bacteroides (13%) and Gram-positive with low GC content (3.7%). Eleven of the isolates have been reported previously and the others microorganisms
remain uncharacterized. The isolated microorganisms here could be a potential source for biotechnological products, such as
cold-active enzymes and secondary metabolites. 相似文献
992.
Moonlighting proteins have two different functions within a single polypeptide chain. Exploring moonlighting enzymes from
the environment using the metagenomic approach is interesting. In the present study, a novel β-glucosidase gene, designated
as bgl1D, with lipolytic activity (renamed Lip1C) was cloned through function-based screening of a metagenomic library from uncultured
soil microorganisms. The deduced amino acid sequence comparison and phylogenetic analysis also indicated that Lip1C and other
putative lipases are closely related. Biochemical characterization demonstrated that the maximum activity of the recombinant
Lip1C protein occurs at pH 8.0 and 30°C using 4-nitrophenyl butyrate as substrate. The putative lipase had an apparent K
m value of 0.88 mmol/L, a k
cat value of 212/min, and a k
cat/K
m value of 241 L/mmol/min. Lip1C exhibited habitat-specific characteristics with 5 mmol/L AlCl3, CuCl2, and LiCl. The characterization of the biochemical properties of Lip1C enhances our understanding of this novel moonlighting
enzyme isolated from a soil metagenome. 相似文献
993.
Gombošová L Lazúrová I Zakuciová M Curová K Kmeťová M Petrášová D Siegfried L 《Folia microbiologica》2011,56(5):367-372
Escherichia coli gene fimA was the most frequent gene that occurred in the intestine of all investigated groups. All subjects with fimA gene had significantly higher values of tumor necrosis factor alpha (TNF-α) and CRP than those with other E. coli genes. There was also a tendency to increased serum interleukin (IL)-6 levels in patients carrying the fimA gene; however, no relation was observed to serum IL-8 and IL-10. Patients with Crohn’s disease had significantly higher IL-6 than
those with ulcerative colitis (UC) and controls. The highest levels of TNF-α were detected in the UC group. There were no
significant differences in serum IL-8 and IL-10 between all three groups. The presence of E. coli gene fimA in the large bowel of patients with IBD is related to the immunological activity of the disease which may be important from
the aspect of therapeutical strategy. 相似文献
994.
Pigozzi MI 《Genetica》2011,139(6):771-777
All extant birds share the same sex-chromosome system: ZZ males and ZW females with striking differences in the stages of
sex-chromosome differentiation between the primitive palaeognathus ratites and the large majority of avian species grouped
within neognaths. Evolutionarily close to ratites is the neotropical order Tinamiformes that has been scarcely explored regarding
their ZW pair morphology and constitution. Tinamous, when compared to ratites, constitute a large group among Palaeognathae,
therefore, exploring the extent of homology between the Z and W chromosomes in this group might reveal key features on the
evolution of the avian sex chromosomes. We mapped MLH1 foci that are crossover markers on pachytene bivalents to determine
the size and localization of the homologous region shared by the Z and W chromosomes in two tinamous: Eudromia elegans and Crypturellus tataupa. We found that the homologous (pseudoautosomal) region differ significantly in size between these two species. They both
have a single recombination event on the long arm of the acrocentric Z and W chromosomes. However, in E. elegans the pseudoautosomal region occupies one-fourth of the W chromosome, while in C. tataupa it is restricted to the tip of the long arm of the W. The W chromosomes in these two species differ in their heterochromatin
content: in E. elegans it shows a terminal euchromatic segment and in C. tataupa is completely heterochromatic. These results show that tinamous have ZW pairs with more diversified stages of differentiation
compared to ratites. Finally, the idea that the avian proto-sex chromosomes started to diverge from the end of the long arm
towards the centromere of an acrocentric pair is discussed. 相似文献
995.
Previous studies have shown that natural disasters, and hurricanes in particular, have led to more deaths than those usually
documented in short post-storm surveys. Such indirect deaths, thought to be related to dietary, stress or pre-existing medical
conditions, can exceed the number of direct deaths and may persist for weeks or even months beyond the event itself. In the
present study, cumulative sum of deviations plots are used to quantify the number of direct and indirect deaths resulting
from Hurricanes Charley, Frances, Ivan and Jeanne that made landfall in Florida in 2004. Results suggest that there was an
elevated mortality for up to 2 months following each storm, resulting in a total of 624 direct and indirect deaths attributable
to the storm. Trauma-related deaths that can be associated directly with the storm account for only ∼4% of the total storm-related
mortality, while indirect mortality accounts for most storm-related deaths. Specifically, a large percentage of the elevated
mortality was associated with heart (34%) and cancer-related deaths (19%), while diabetes (5%) and accident-related deaths
(9%) account for a smaller but still significant percentage of the elevated mortality. The results further suggest that the
elevated mortality was the result of additional deaths that would not have otherwise occurred within that 5 month period,
and not simply a clustering of deaths that were inevitable between 1 August and 31 December 2004. The elevated mortality identified
in this study is significantly greater than the official count of 31 direct and 113 indirect deaths resulting from the four
hurricanes combined. This suggests a need for improved mortality counts and surveillance in order to better evaluate and identify
effective prevention policies, and to identify preventable deaths. 相似文献
996.
This paper presents a new approach, in applying the Pierce two-node model, to predict local skin temperatures of individual
body parts with good accuracy. In this study, local skin temperature measurements at 24 sites on the bodies of 11 human subjects
were carried out in a controlled environment under three different indoor conditions (i.e. neutral, warm and cold). The neutral
condition measurements were used to adjust the local skin set-points in the model for each body part. Additional modifications
to the calculation algorithm were introduced corresponding to different body parts. The local core set-points were then calculated,
using a line search method, as the input values that allow the model to predict the skin temperatures with maximum deviation
of ±0.1°C for the neutral condition. The model predictability was verified for the other two indoor conditions, and the results
show that the modified model predicts local skin temperatures with average deviation of ±0.3°C. 相似文献
997.
Pagourelias ED Zorou PG Tsaligopoulos M Athyros VG Karagiannis A Efthimiadis GK 《International journal of biometeorology》2011,55(5):657-663
Carbon dioxide (CO(2)) balneotherapy is a kind of remedy with a wide spectrum of applications which have been used since the Middle Ages. However, its potential use as an adjuvant therapeutic option in patients with cardiovascular disease is not yet fully clarified. We performed a thorough review of MEDLINE Database, EMBASE, ISI WEB of Knowledge, COCHRANE database and sites funded by balneotherapy centers across Europe in order to recognize relevant studies and aggregate evidence supporting the use of CO(2) baths in various cardiovascular diseases. The three main effects of CO(2) hydrotherapy during whole body or partial immersion, including decline in core temperature, an increase in cutaneous blood flow, and an elevation of the score on thermal sensation, are analyzed on a pathophysiology basis. Additionally, the indications and contra-indications of the method are presented in an evidence-based way, while the need for new methodologically sufficient studies examining the use of CO(2) baths in other cardiovascular substrates is discussed. 相似文献
998.
Zhu CH Lu FP He YN Zhang JK Du LX 《Journal of industrial microbiology & biotechnology》2007,34(4):271-278
A fermentation medium for avilamycin production by Streptomyces viridochromogenes Tü57-1 has been optimized. Important components and their concentrations were investigated using fractional factorial design
and Box–Behnken Design. The results showed that soybean flour, soluble starch, MgSO4·7H2O and CaCl2·2H2O are important for avilamycin production. A polynomial model related to medium components and avilamycin yield had been established.
A high coefficient of determination (R
2 = 0.92) was obtained that indicated good agreement between the experimental and predicted values of avilamycin yield. Student’s
T-test of each coefficient showed that all the linear and quadratic terms had significant effect (P > |T| < 0.05) on avilamycin yield. The significance of tested components was related to MgSO4·7H2O (0.37 g/L), CaCl2·2H2O (0.39 g/L), soybean flour (21.97 g/L) and soluble starch (37.22 g/L). The yield of avilamycin reached 88.33 ± 0.94 mg/L
(p < 0.05) that was 2.8-fold the initial yield. 相似文献
999.
Youhei Tanaka Naohiro Hayashibara Tomoya Enokido Makoto Takizawa 《Cluster computing》2007,10(1):81-93
In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can
be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how
application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase
commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage
of mobile agent technologies where a program can move from a computer to another computer in networks. An application program
to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile
agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent
model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation
map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision
on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the
computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional
agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold
objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty
computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected
by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty,
the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver
the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes
to abort the routing subagent if some computer is faulty.
相似文献
Makoto TakizawaEmail: |
1000.