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41.
Toluene gas phase biofiltration by Paecilomyces lilacinus and isolation and identification of a hydrophobin protein produced thereof 总被引:1,自引:0,他引:1
Vigueras G Shirai K Martins de Souza D Martins D Franco TT Fleuri LF Revah S 《Applied microbiology and biotechnology》2008,80(1):147-154
Paecilomyces lilacinus consumed toluene as the sole carbon source in a gas-phase biofilter packed with perlite obtaining an average elimination capacity of 50 g m(-3) h(-1), a removal efficiency of 53%, and a final biomass of 31.6 mg biomass g dry support(-1). Hydrophobin proteins from the mycelium produced in the biofilter were purified by formic acid extraction and precipitated by electrobubbling, and the molecular weight was found to be 10.6 +/- 0.3 kDa. The peptide mass fingerprinting analysis of the purified hydrophobin by matrix-assisted laser desorption/ionization time-of-flight resulted in the identification of two peptides that presented high homology with sequences of class I hydrophobin proteins from other ascomycetous fungi when compared against the National Center for Biotechnology Information database. The yield of hydrophobin (PLHYD) from P. lilacinus was 1.1 mg PLHYD g biomass(-1). These proteins modified the hydrophobicity of Teflon by lowering the contact angle from 130.1 (+/-2) degrees to 57.0 (+/-5) degrees supporting hot sodium dodecyl sulfate washing. This work is the first report about biodegradation of toluene by the nematophagous fungus P. lilacinus in a gas-phase biofilter and the identification of its hydrophobin protein. 相似文献
42.
Norimah AK H. C. Koo Hamid Jan JM Mohd Nasir MT S. Y. Tan Mahendran Appukutty Nurliyana AR Frank Thielecke Sinead Hopkins M. K. Ong C. Ning E. S. Tee 《PloS one》2015,10(10)
Background
Diets rich in whole grain are associated with several health benefits. Little is known however, about whole grain consumption patterns in Malaysia. The aim of this study was to assess whole grain intakes and dietary source in Malaysian children and adolescents.Methods
This analysis is from the MyBreakfast study, a national cross sectional study investigating eating habits among primary and secondary school children throughout Malaysia, conducted in 2013. Children (n = 5,165) and adolescents (n = 2,947) who completed two days of dietary assessment using a food record or recall respectively were included. The whole grain content of foods was estimated mainly through the use of quantitative ingredient declarations on food labels. All wholegrain foods were considered irrespective of the amount of whole grain they contained.Results
Overall, only 25% of children and 19% of adolescents were wholegrain consumers. Mean daily intakes in the total sample were 2.3g/d (SD 5.8g/d) in children and 1.7g/d (SD 4.7g/d) in adolescents and in the consumer’s only sample, mean intakes reached 9.1g/d (SD 8.6) and 9.2g/d (SD 7.1g/d) respectively. Wheat was the main grain source of whole grain while ready to eat breakfast cereals and hot cereals were the main food contributors. Less than 3% of the children and adolescents reached the US quantitative whole grain recommendation of 48g/day.Conclusion
Whole grain is consumed by only a minority of Malaysian children and adolescents and even among consumers, intakes are well below recommendations. Efforts are needed to firstly understand the barriers to whole grain consumption among Malaysian children in order to design effective health promotion initiatives to promote an increase in whole grain consumption. 相似文献43.
44.
Tim Downing David J. Lynn Sarah Connell Andrew T. Lloyd AK Fazlul Haque Bhuiyan Pradeepa Silva Arifa N. Naqvi Rahamame Sanfo Racine-Samba Sow Baitsi Podisi Cliona O’Farrelly Olivier Hanotte Daniel G. Bradley 《Immunogenetics》2009,61(4):303-314
There have been significant evolutionary pressures on the chicken during both its speciation and its subsequent domestication
by man. Infectious diseases are expected to have exerted strong selective pressures during these processes. Consequently,
it is likely that genes associated with disease susceptibility or resistance have been subject to some form of selection.
Two genes involved in the immune response (interferon-γ and interleukin 1-β) were selected for sequencing in diverse chicken
populations from Pakistan, Sri Lanka, Bangladesh, Kenya, Senegal, Burkina Faso and Botswana, as well as six outgroup samples
(grey, green, red and Ceylon jungle fowl and grey francolin and bamboo partridge). Haplotype frequencies, tests of neutrality,
summary statistics, coalescent simulations and phylogenetic analysis by maximum likelihood were used to determine the population
genetic characteristics of the genes. Networks indicate that these chicken genes are most closely related to the red jungle
fowl. Interferon-γ had lower diversity and considerable coding sequence conservation, which is consistent with its function
as a key inflammatory cytokine of the immune response. In contrast, the pleiotropic cytokine interleukin 1-β had higher diversity
and showed signals of balancing selection moderated by recombination, yielding high numbers of diverse alleles, possibly reflecting
broader functionality and potential roles in more diseases in different environments.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
45.
A codon-based model designed to describe lentiviral evolution 总被引:7,自引:6,他引:1
46.
Evolutionary relationships of human populations on a global scale 总被引:28,自引:2,他引:26
Using gene frequency data for 29 polymorphic loci (121 alleles), we
conducted a phylogenetic analysis of 26 representative populations from
around the world by using the neighbor-joining (NJ) method. We also
conducted a separate analysis of 15 populations by using data for 33
polymorphic loci. These analyses have shown that the first major split of
the phylogenetic tree separates Africans from non-Africans and that this
split occurs with a 100% bootstrap probability. The second split separates
Caucasian populations from all other non-African populations, and this
split is also supported by bootstrap tests. The third major split occurs
between Native American populations and the Greater Asians that include
East Asians (mongoloids), Pacific Islanders, and Australopapuans (native
Australians and Papua New Guineans), but Australopapuans are genetically
quite different from the rest of the Greater Asians. The second and third
levels of population splitting are quite different from those of the
phylogenetic tree obtained by Cavalli- Sforza et al. (1988), where
Caucasians, Northeast Asians, and Ameridians from the Northeurasian
supercluster and the rest of non- Africans form the Southeast Asian
supercluster. One of the major factors that caused the difference between
the two trees is that Cavalli-Sforza et al. used unweighted pair-group
method with arithmetic mean (UPGMA) in phylogenetic inference, whereas we
used the NJ method in which evolutionary rate is allowed to vary among
different populations. Bootstrap tests have shown that the UPGMA tree
receives poor statistical support whereas the NJ tree is well supported.
Implications that the phylogenetic tree obtained has on the current
controversy over the out-of-Africa and the multiregional theories of human
origins are discussed.
相似文献
47.
In the present investigation, a simple technique was employed to obtain cross-sections of unloaded and nifedipine loaded chitosan microspheres. Microspheres, adhering to a polymerized resin block, were cut with an ultramicrotome and viewed with a scanning electron microscope. Unloaded microspheres exhibited a uniform dense matrix structure while crystals of nifedipine were clearly visible in the drug-loaded microspheres. At 2% drug loading, however, no crystals could be seen in the microspheres indicating that either the drug was molecularly dispersed or dissolved in the matrix at this concentration. This was confirmed by powder X-ray diffractometry studies where no peak due to crystalline nifedipine was observed. At high Span 85 concentration (1.5% w/v), the external surface of the microspheres collapsed, but the internal structure remained dense. When the drug was dispersed in the chitosan solution with stirring during preparation, the entrapment was good and the shape of the crystals was changed. The internal structure of the microspheres following dissolution exhibited the presence of pores. 相似文献
48.
49.
50.
We recently reported that bile salts play a role in the regulation of mucin
secretion by cultured dog gallbladder epithelial cells. In this study we
have examined whether bile salts also influence mucin secretion by the
human epithelial colon cell line LS174T. Solutions of bile salts were
applied to monolayers of LS174T cells. Mucin secretion was quantified by
measuring the secretion of [3H]GlcNAc labeled glycoproteins. Both
unconjugated bile salts as well as taurine conjugated bile salts stimulated
mucin secretion by the colon cells in a dose-dependent fashion. Hydrophobic
bile salts were more potent stimulators than hydrophilic bile salts. Free
(unconjugated) bile salts were more stimulatory compared with their taurine
conjugated counterparts. Stimulation of mucin secretion by LS174T cells was
found to occur at much lower bile salt concentrations than in the
experiments with the dog gallbladder epithelial cells. The protein kinase C
activators PMA and PDB had no stimulatory effect on mucin secretion. We
conclude that mucin secretion by the human colon epithelial cell line
LS174T is regulated by bile salts. We suggest that regulation of mucin
secretion by bile salts might be a common mechanism, by which different
epithelia protect themselves against the detergent action of bile salts, to
which they are exposed throughout the gastrointestinal tract.
相似文献