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751.
Mark Kowarsky Chiara Anselmi Kohji Hotta Paolo Burighel Giovanna Zaniolo Federico Caicci Benyamin Rosental Norma F. Neff Katherine J. Ishizuka Karla J. Palmeri Jennifer Okamoto Tal Gordon Irving L. Weissman Stephen R. Quake Lucia Manni Ayelet Voskoboynik 《Cell reports》2021,34(4):108681
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752.
The concentration of the toxic elements Ag, As, Cd, Co, Mn, Mo, Pb, Se, and U and the elements Al, Mg, Cu, Fe, and Zn in human hair samples of population living in the north of the Negev Desert in Israel was determined. The study population consisted of three subgroups: Jewish urban population, Bedouin urban population, and Bedouins living in unrecognized villages (the “dispersion”). The main focus is on the differences between these subgroups in an attempt to explore factors responsible for the variation in trace metal contents in hair samples. The results show that the level of several elements, particularly Ag, Mn, and Pb, in the female Bedouin group significantly differed from the other groups in the study. Exploring the reasons for these differences, we concluded that the lifestyle of those women is the main cause. The female Bedouin subgroup is exposed to heavy metals from kitchen utensils, jewelry, and makeup. Therefore, differences in the heavy metal concentration in the hair samples of this group were attributed to the traditional unique lifestyle and social behavior of the females in the Bedouin society. 相似文献
753.
754.
Freeze-dried, alginate-based beads, used for the immobilization of a denitrifying bacterium (Pseudomonas sp.), were filled with different concentrations (10%, 20%, 30% and 40%, w/w) of granular starch. The beads were incubated
under denitrifying conditions in laboratory-scale, flow-through columns and monitored for changes in their physical and denitrifying
properties. Freeze-dried beads containing high concentrations of starch were found to have better mechanical and denitrifying
properties than beads containing low concentrations of this filler. Nitrate removal by the beads was found to be correlated
with their starch content. Nitrite accumulation, as a result of incomplete denitrification, increased with the decrease in
starch content of the beads. Nitrite in the outlet of the columns was measured in all types of beads during the initial phase
of incubation but was undetectable, with the exception of beads with the lowest starch content, at later stages of incubation.
Received: 9 November 1998 / Received revision: 3 February 1999 / Accepted: 5 February 1999 相似文献
755.
Liliia I. Butiaeva Tal Slutzki Hannah E. Swick Clément Bourguignon Sarah C. Robins Xiaohong Liu Kai-Florian Storch Maia V. Kokoeva 《Cell metabolism》2021,33(7):1433-1448.e5
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756.
Salt-adapted and control cells of the cultivated potato, Solanum tuberosum cultivar Russet Burbank, untreated or treated with 5-azacytidine (an inhibitor of DNA methylation), were compared with respect to: a) % of cytosine methylation in total nuclear DNA, as determined by HPLC; b) fresh and dry weight. Adapted and control cells were compared also with respect to % of cytosine methylation in DNA, which was purified from DNaseI-partially-digested chromatin and size fractionated by electrophoresis in agarose gels. The growth (represented by dry weight) of the NaCl-adapted cells in saline medium lacking 5-azacytidine was similar to that of control cells in standard medium. The adaptation of the cells was correlated with some increase (+16%) of methylation in total DNA and with a much greater increase in the lower molecular weight DNA fractions which were obtained from the presumably more active chromatin. As expected, the treatment of the cells with the methylation inhibitor induced a decrease in the level of methylation. The decrease of methylation, however, was much greater in the adapted cells, whose dry weight, unlike in the control, was not affected by this treatment.Abbreviations 5-azaCyt
5-azacytidine
- C
cytidine
- 2,4-D
2,4 dichlorophenoxyacetic acid
- DW
dry weight
- EDTA
ethylenediaminetetraacetic acid
- FW
fresh weight
- HPLC
high performance liquid chromatography
- m5Cyt
5 methyl cytidine
- RB
Russet Burbank
- SDS
sodium dodecyl sulfate
- TE
10 mM Tris and 1 mM EDTA
- Tris
Tris [hydroxymethyl] aminomethane 相似文献
757.
758.
Elisabetta Carata Clelia Peano Salvatore M Tredici Francesco Ferrari Adelfia Talà Giorgio Corti Silvio Bicciato Gianluca De Bellis Pietro Alifano 《Microbial cell factories》2009,8(1):18-15
Background
There is evidence from previous works that bacterial secondary metabolism may be stimulated by genetic manipulation of RNA polymerase (RNAP). In this study we have used rifampicin selection as a strategy to genetically improve the erythromycin producer Saccharopolyspora erythraea. 相似文献759.
Oomen RJ Benito B Sentenac H Rodríguez-Navarro A Talón M Véry AA Domingo C 《The Plant journal : for cell and molecular biology》2012,71(5):750-762
We have investigated OsHKT2;1 natural variation in a collection of 49 cultivars with different levels of salt tolerance and geographical origins. The effect of identified polymorphism on OsHKT2;1 activity was analysed through heterologous expression of variants in Xenopus oocytes. OsHKT2;1 appeared to be a highly conserved protein with only five possible amino acid substitutions that have no substantial effect on functional properties. Our study, however, also identified a new HKT isoform, No-OsHKT2;2/1 in Nona Bokra, a highly salt-tolerant cultivar. No-OsHKT2;2/1 probably originated from a deletion in chromosome 6, producing a chimeric gene. Its 5' region corresponds to that of OsHKT2;2, whose full-length sequence is not present in Nipponbare but has been identified in Pokkali, a salt-tolerant rice cultivar. Its 3' region corresponds to that of OsHKT2;1. No-OsHKT2;2/1 is essentially expressed in roots and displays a significant level of expression at high Na(+) concentrations, in contrast to OsHKT2;1. Expressed in Xenopus oocytes or in Saccharomyces cerevisiae, No-OsHKT2;2/1 exhibited a strong permeability to Na(+) and K(+) , even at high external Na(+) concentrations, like OsHKT2;2, and in contrast to OsHKT2;1. Our results suggest that No-OsHKT2;2/1 can contribute to Nona Bokra salt tolerance by enabling root K(+) uptake under saline conditions. 相似文献
760.