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1.
Samples of whole blood were obtained from 51 patients with newly diagnosed colorectal cancer as well as from 76 patients with neoplastic colorectal polyp, and from 30 healthy blood bank donors. Selenium was determined by the fluorimetric method. Significantly decreased selenium concentrations of blood samples from patients with colorectal cancer and villous adenoma were found. There was not any correlation between the blood selenium levels of patients with adenomatous polyp and the severity of dysplasia in removed polyps. The lowest mean selenium level in patients with villous adenoma indicates that selenium deficiency may be an important factor in the development of colorectal cancer arising from villous adenomas. 相似文献
2.
Brassinolide-Induced Elongation of Inner Tissues of Segments of Squash (Cucurbita maxima Duch.) Hypocotyls 总被引:1,自引:0,他引:1
Brassinolide (BR) stimulated elongation of etiolated squashhypocotyl segments with outer tissues removed, as well as thatof unpeeled segments, while IAA has no effect on peeled segments.BR changed the mechanical properties of cell walls of the innertissue. The inner tissue is probably the target tissue in BR-inducedelongation.
1Dr. Susumu Kuraishi died in 1993. 相似文献
3.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
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Thorsten Klampfl Jelena D. Milosevic Ana Puda Andreas Sch?negger Klaudia Bagienski Tiina Berg Ashot S. Harutyunyan Bettina Gisslinger Elisa Rumi Luca Malcovati Daniela Pietra Chiara Elena Matteo Giovanni Della Porta Lisa Pieri Paola Guglielmelli Christoph Bock Michael Doubek Dana Dvorakova Nada Suvajdzic Dragica Tomin Natasa Tosic Zdenek Racil Michael Steurer Sonja Pavlovic Alessandro M. Vannucchi Mario Cazzola Heinz Gisslinger Robert Kralovics 《PloS one》2013,8(10)
Exome sequencing of primary tumors identifies complex somatic mutation patterns. Assignment of relevance of individual somatic mutations is difficult and poses the next challenge for interpretation of next generation sequencing data. Here we present an approach how exome sequencing in combination with SNP microarray data may identify targets of chromosomal aberrations in myeloid malignancies. The rationale of this approach is that hotspots of chromosomal aberrations might also harbor point mutations in the target genes of deletions, gains or uniparental disomies (UPDs). Chromosome 11 is a frequent target of lesions in myeloid malignancies. Therefore, we studied chromosome 11 in a total of 813 samples from 773 individual patients with different myeloid malignancies by SNP microarrays and complemented the data with exome sequencing in selected cases exhibiting chromosome 11 defects. We found gains, losses and UPDs of chromosome 11 in 52 of the 813 samples (6.4%). Chromosome 11q UPDs frequently associated with mutations of CBL. In one patient the 11qUPD amplified somatic mutations in both CBL and the DNA repair gene DDB1. A duplication within MLL exon 3 was detected in another patient with 11qUPD. We identified several common deleted regions (CDR) on chromosome 11. One of the CDRs associated with de novo acute myeloid leukemia (P=0.013). One patient with a deletion at the LMO2 locus harbored an additional point mutation on the other allele indicating that LMO2 might be a tumor suppressor frequently targeted by 11p deletions. Our chromosome-centered analysis indicates that chromosome 11 contains a number of tumor suppressor genes and that the role of this chromosome in myeloid malignancies is more complex than previously recognized. 相似文献
6.
Lilian?Rumi?Tsuruta Mariana?Lopes dos Santos Fernanda?Perez?Yeda Oswaldo?Keith?Okamoto Ana?Maria?MoroEmail author 《Applied microbiology and biotechnology》2016,100(23):10031-10041
Genetic characterization of protein-producing clones represents additional value to cell line development. In the present study, ten Per.C6 clones producing a Rebmab100 monoclonal antibody were selected using two cloning methods: six clones originated from limiting dilution cloning and four by the automated colony picker ClonePix FL. A stability program was performed for 50 generations, including 4 batches distributed along the timeframe to determine specific productivity (Qp) maintenance. Four stable clones (two from limiting dilution and two from ClonePix FL) were further evaluated. The relative mRNA expression levels of both heavy chain (HC) and light chain (LC) genes were verified at generations 0, 30–35, and 50–55 of the stability program. At generations 0 and 30–35, LC gene expression level was higher than HC gene, whereas at generation 50–55, the opposite prevailed. A high correlation was observed between Qp and HC or LC mRNA expression level for all clones at each generation analyzed along the continuous culture. The mRNA stability study was performed at steady-state culture. The LC gene displayed a higher half-life and lower decay constant than HC gene, accounting for the higher observed expression level of LC mRNA in comparison to HC mRNA. Clone R6 was highlighted due its high Qp, mRNA expression levels, and mRNA stability. Besides the benefits of applying genetic characterization for the selection of stable and high-producing clones, the present study shows for the first time the correlation between Qp and HC or LC expression levels and also mRNA stability in clones derived from human cell line Per.C6(®). 相似文献
7.
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Carvalho OS Cardoso PC Lira PM Rumi A Roche A Berne E Müller G Caldeira RL 《Memórias do Instituto Oswaldo Cruz》2004,99(5):503-507
The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results. 相似文献
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10.
Sato T Ozaki R Kamo S Hara Y Konishi S Isobe Y Saitoh S Harada H 《Biochimica et biophysica acta》2003,1622(3):145-150
2',3'-Dihydrophylloquinone (dihydro-K1) is a hydrogenated form of vitamin K1 (K1), which is produced during the hydrogenation of K1-rich plant oils. In this study, we found that dihydro-K1 counteracts the sodium warfarin-induced prolonged blood coagulation in rats. This indicates that dihydro-K1 functions as a cofactor in the posttranslational gamma-carboxylation of the vitamin K-dependent coagulation factors. It was also found that dihydro-K1 as well as K1 inhibits the decreasing effects of warfarin on the serum total osteocalcin level. In rats, dihydro-K1 is well absorbed and detected in the tissues of the brain, pancreas, kidney, testis, abdominal aorta, liver and femur. K1 is converted to menaquinone-4 (MK-4) in all the above-mentioned tissues, but dihydro-K1 is not. The unique characteristic of dihydro-K1 possessing vitamin K activity and not being converted to MK-4 would be useful in revealing the as yet undetermined physiological function of the conversion of K1 to MK-4. 相似文献