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161.
Grube M Muter O Strikauska S Gavare M Limane B 《Journal of industrial microbiology & biotechnology》2008,35(11):1545-1549
Previous studies showed that cabbage leaf extract (CLE) added to the growth medium can noticeably promote the degradation
of nitro aromatic compounds by specific consortium of bacteria upon their growth. For further development of the approach
for contaminated soil remediation it was necessary to evaluate the qualitative and/or quantitative composition of different
origin CLE and their relevance on the growth of explosives-degrading bacteria. Six CLE (different by species, cultivars and
harvesting time) were tested and used as additives to the growth medium. It was shown that nitro aromatic compounds can be
identified in the FT-IR absorption spectra by the characteristic band at 1,527 cm−1, and in CLE by the characteristic band at 1,602 cm−1. The intensity of the CLE band at 1,602 cm−1 correlated with the concentration of total nitrogen (R
2 = 0.87) and decreased upon the growth of bacteria. The content of nitrogen in CLE differed (0.22–1.00 vol.%) and significantly
influenced the content of total carbohydrates (9.50–16.00% DW) and lipids [3.90–9.90% dry weight (DW)] accumulated in bacterial
cells while the content of proteins was similar in all samples. Though this study showed quantitative differences in the composition
of the studied CLE and the response of bacterial cells to the composition of the growth media, and proved the potential of
this additive for remediation of contaminated soil. It was shown that analysis of CLE and monitoring of the conversion of
nitro aromatic compounds can be investigated by FT-IR spectroscopy as well as by conventional chemical methods. 相似文献
162.
Gudrun A. Rappold Anja Henke Marita Pohlschmid Titus H. J. Huisman 《Human genetics》1992,88(5):573-578
Summary DNA patterns from a pseudoautosomal variable number tandem repeat-like minisatellite (locus DXYS20) were compared in two samples: a Caucasian and a Black sample. We defined 3 types of DNA patterns named A, B and C, and found that these patterns have different frequencies in the Caucasian and Black groups. A set of alleles (the C group) in 48% of the Black sample is not found in the Caucasian sample. We also found a greater degree of fragment-size variability among Black individuals than among those of Caucasian origin. The large degree of ethnic variation indicates that this locus will be useful in population genetic studies. 相似文献
163.
Laisana Shakirova Mara Grube Marita Gavare Lilija Auzina Peteris Zikmanis 《Journal of industrial microbiology & biotechnology》2013,40(1):85-93
Changes in the cell surface hydrophobicity (CSH) of probiotic bacteria Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 and the survival of these cells were examined in response to varied cultivation conditions and adverse environmental conditions. An inverse linear relationship (P < 0.01) was detected between the CSH of intact L. acidophilus La5 and B. lactis Bb12 and survival of cells subjected to subsequent freezing/thawing, long-term storage or exposure to mineral and bile acids. The observed relationships were supported by significant correlations between the CSH and changes in composition of the cell envelopes (proteins, lipids and carbohydrates) of L. acidophilus La5 and B. lactis Bb12 examined using FT-IR spectroscopy and conventional biochemical analysis methods. The results also suggest that the estimates of hydrophobicity, being a generalized characteristic of cell surfaces, are important parameters to predict the ability of intact probiotic bacteria to endure extreme environments and therefore should be monitored during cultivation. A defined balance of cell components, which can be characterized by the reduced CSH values, apparently helps to ensure the resistance, improved viability and hence the overall probiotic properties of bacteria. 相似文献
164.
Jane M. Marita Ronald D. Hatfield David M. Rancour Kenneth E. Frost 《The Plant journal : for cell and molecular biology》2014,78(5):850-864
Grasses, such as Zea mays L. (maize), contain relatively high levels of p ‐ coumarates (pCA) within their cell walls. Incorporation of pCA into cell walls is believed to be due to a hydroxycinnamyl transferase that couples pCA to monolignols. To understand the role of pCA in maize development, the p ‐ coumaroyl CoA:hydroxycinnamyl alcohol transferase (pCAT) was isolated and purified from maize stems. Purified pCAT was subjected to partial trypsin digestion, and peptides were sequenced by tandem mass spectrometry. TBLASTN analysis of the acquired peptide sequences identified a single full‐length maize cDNA clone encoding all the peptide sequences obtained from the purified enzyme. The cDNA clone was obtained and used to generate an RNAi construct for suppressing pCAT expression in maize. Here we describe the effects of suppression of pCAT in maize. Primary screening of transgenic maize seedling leaves using a new rapid analytical platform was used to identify plants with decreased amounts of pCA. Using this screening method, mature leaves from fully developed plants were analyzed, confirming reduced pCA levels throughout plant development. Complete analysis of isolated cell walls from mature transgenic stems and leaves revealed that lignin levels did not change, but pCA levels decreased and the lignin composition was altered. Transgenic plants with the lowest levels of pCA had decreased levels of syringyl units in the lignin. Thus, altering the levels of pCAT expression in maize leads to altered lignin composition, but does not appear to alter the total amount of lignin present in the cell walls. 相似文献
165.
Katariina Hannula-Jouppi Mari Muurinen Marita Lipsanen-Nyman Lovisa E Reinius Sini Ezer Dario Greco Juha Kere 《Epigenetics》2014,9(3):351-365
DNA methylation is a hallmark of genomic imprinting and differentially methylated regions (DMRs) are found near and in imprinted genes. Imprinted genes are expressed only from the maternal or paternal allele and their normal balance can be disrupted by uniparental disomy (UPD), the inheritance of both chromosomes of a chromosome pair exclusively from only either the mother or the father. Maternal UPD for chromosome 7 (matUPD7) results in Silver-Russell syndrome (SRS) with typical features and growth retardation, but no gene has been conclusively implicated in SRS. In order to identify novel DMRs and putative imprinted genes on chromosome 7, we analyzed eight matUPD7 patients, a segmental matUPD7q31-qter, a rare patUPD7 case and ten controls on the Infinium HumanMethylation450K BeadChip with 30 017 CpG methylation probes for chromosome 7. Genome-scale analysis showed highly significant clustering of DMRs only on chromosome 7, including the known imprinted loci GRB10, SGCE/PEG10, and PEG/MEST. We found ten novel DMRs on chromosome 7, two DMRs for the predicted imprinted genes HOXA4 and GLI3 and one for the disputed imprinted gene PON1. Quantitative RT-PCR on blood RNA samples comparing matUPD7, patUPD7, and controls showed differential expression for three genes with novel DMRs, HOXA4, GLI3, and SVOPL. Allele specific expression analysis confirmed maternal only expression of SVOPL and imprinting of HOXA4 was supported by monoallelic expression. These results present the first comprehensive map of parent-of-origin specific DMRs on human chromosome 7, suggesting many new imprinted sites. 相似文献
166.
Vafa M Maiga B Berzins K Hayano M Bereczky S Dolo A Daou M Arama C Kouriba B Färnert A Doumbo OK Troye-Blomberg M 《Microbes and infection / Institut Pasteur》2007,9(9):1043-1048
In this study, we compared the genotype and allele frequencies of the IL-10 -1087 A/G and IL-4 -590 C/T single nucleotide polymorphisms in asymptomatic subjects of two sympatric ethnic tribes differing in susceptibility to malaria, the Fulani and the Dogon in Mali. The genotype data was correlated with ethnicity and malariometric indexes. A statistically significant inter-ethnic difference in allele and genotype frequency for both loci was noted (P<0.0001). Within the Fulani, the prevalence of Plasmodium falciparum infection, as detected by both microscopy and PCR, was associated with the IL-4 -590 T allele (P=0.005 and P=0.0005, respectively), whereas, no such associations were seen in the Dogon. Inter-ethnic differences in spleen rates, higher in the Fulani than the Dogon, were seen between T carriers (TT and CT) of both groups (P<0.0001). Parasite densities and number of concurrent clones did not vary between IL-4 genotypes within any of the studied groups. These results suggest an association between the IL-4 -590 T allele and P. falciparum prevalence within the Fulani but not the Dogon. No associations between IL-10 genotypes and studied malariometric indexes were observed in any of the two communities. 相似文献
167.
Robert Lowe Marita G. Overhoff Sreeram V. Ramagopalan James C. Garbe James Koh Martha R. Stampfer David H. Beach Vardhman K. Rakyan Cleo L. Bishop 《Genome biology》2015,16(1)
BackgroundCellular senescence is a stable arrest of proliferation and is considered a key component of processes associated with carcinogenesis and other ageing-related phenotypes. Here, we perform methylome analysis of actively dividing and deeply senescent normal human epithelial cells.ResultsWe identify senescence-associated differentially methylated positions (senDMPs) from multiple experiments using cells from one donor. We find that human senDMP epigenetic signatures are positively and significantly correlated with both cancer and ageing-associated methylation dynamics. We also identify germline genetic variants, including those associated with the p16INK4A locus, which are associated with the presence of in vivo senDMP signatures. Importantly, we also demonstrate that a single senDMP signature can be effectively reversed in a newly-developed protocol of transient senescence reversal.ConclusionsThe senDMP signature has significant potential for understanding some of the key (epi)genetic etiological factors that may lead to cancer and age-related diseases in humans.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0748-4) contains supplementary material, which is available to authorized users. 相似文献168.
Sharmila Vaz Nathan Wilson Marita Falkmer Angela Sim Melissa Scott Reinie Cordier Torbj?rn Falkmer 《PloS one》2015,10(8)
Objective
Teachers'' attitudes toward inclusion are often based on the practical implementation of inclusive education rather than a specific ideology and understanding of inclusiveness. This study aimed to identify the factors associated with primary school teachers'' attitudes towards inclusion of students with all disabilities in regular schools.Method
Seventy four primary school teachers participated in a cross-sectional survey conducted in Western Australia. Teachers'' attitudes and efficacy toward integration of students with disabilities were measured using the Opinions Relative to Integration of Students with Disabilities scale and Bandura''s Teacher Efficacy scale respectively.Results
Four teacher attributes—age, gender, teaching self-efficacy and training collectively explained 42% of the variability in teachers'' attitude toward including students with disabilities.Conclusion
The current study further contributes to the accumulation of knowledge that can unpack the complex pattern of factors that should be considered to promote positive attitudes towards inclusive schools. 相似文献169.
Maija Aalto Marita Potila Eino Kulonen 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,587(4):606-617
Buffer-soluble and pronase-liberated glycoproteins from experimental granulation tissue were fractionated by gel filtration and DEAE-cellulose chromatography. The age of the granuloma was reflected in the gel filtration pattern. Two glycoproteins were isolated, purified to homogeneity and analyzed for their carbohydrate and amino acid compositions.The collagen synthesis in embryonic chick tendon cells was measured in the presence of these fractions, which were found to be inhibiting even at 10?6 M. These glycoproteins may be significant in the feedback regulation of the development of granulation tissue and fibrosis. 相似文献
170.
Brian J Hemens Anne Holbrook Marita Tonkin Jean A Mackay Lorraine Weise-Kelly Tamara Navarro Nancy L Wilczynski R Brian Haynes 《Implementation science : IS》2011,6(1):1-17