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81.
Sidders B Withers M Kendall SL Bacon J Waddell SJ Hinds J Golby P Movahedzadeh F Cox RA Frita R Ten Bokum AM Wernisch L Stoker NG 《Genome biology》2007,8(12):R265-13
We describe an analysis, applicable to any spotted microarray dataset produced using genomic DNA as a reference, that quantifies prokaryotic levels of mRNA on a genome-wide scale. Applying this to Mycobacterium tuberculosis, we validate the technique, show a correlation between level of expression and biological importance, define the complement of invariant genes and analyze absolute levels of expression by functional class to develop ways of understanding an organism's biology without comparison to another growth condition. 相似文献
82.
José MC Ribeiro Bruno Arcà Fabrizio Lombardo Eric Calvo My Van Phan Prafulla K Chandra Stephen K Wikel 《BMC genomics》2007,8(1):1-27
Background
The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comParative analyses. In comParative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (a basal eudicot). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution of simple sequence repeats (SSRs) and longer dispersed repeats (SDR), and patterns of nucleotide composition.Results
The Nuphar [GenBank:NC_008788] and Ranunculus [GenBank:NC_008796] plastid genomes share characteristics of gene content and organization with many other chloroplast genomes. Like other plastid genomes, these genomes are A+T-rich, except for rRNA and tRNA genes. Detailed comparisons of Nuphar with Nymphaea, another Nymphaeaceae, show that more than two-thirds of these genomes exhibit at least 95% sequence identity and that most SSRs are shared. In broader comparisons, SSRs vary among genomes in s of abundance and length and most contain repeat motifs based on A and T nucleotides.Conclusion
SSR and SDR abundance varies by genome and, for SSRs, is proportional to genome size. Long SDRs are rare in the genomes assessed. SSRs occur less frequently than predicted and, although the majority of the repeat motifs do include A and T nucleotides, the A+T bias in SSRs is less than that predicted from the underlying genomic nucleotide composition. In codon usage third positions show an A+T bias, however variation in codon usage does not correlate with differences in A+T-richness. Thus, although plastome nucleotide composition shows "A+T richness", an A+T bias is not apparent upon more in-depth analysis, at least in these aspects. The pattern of evolution in the sequences identified as ycf15 and ycf68 is not consistent with them being protein-coding genes. In fact, these regions show no evidence of sequence conservation beyond what is normal for non-coding regions of the IR. 相似文献83.
Miyamoto S Ronsein GE Prado FM Uemi M Corrêa TC Toma IN Bertolucci A Oliveira MC Motta FD Medeiros MH Mascio PD 《IUBMB life》2007,59(4-5):322-331
The decomposition of lipid hydroperoxides (LOOH) into peroxyl radicals is a potential source of singlet molecular oxygen ((1)O(2)) in biological systems. Recently, we have clearly demonstrated the generation of (1)O(2) in the reaction of lipid hydroperoxides with biologically important oxidants such as metal ions, peroxynitrite and hypochlorous acid. The approach used to unequivocally demonstrate the generation of (1)O(2) in these reactions was the use of an isotopic labeled hydroperoxide, the (18)O-labeled linoleic acid hydroperoxide, the detection of labeled compounds by HPLC coupled to tandem mass spectrometry (HPLC-MS/MS) and the direct spectroscopic detection and characterization of (1)O(2) light emission. Using this approach we have observed the formation of (18)O-labeled (1)O(2) by chemical trapping of (1)O(2) with anthracene derivatives and detection of the corresponding labeled endoperoxide by HPLC-MS/MS. The generation of (1)O(2) was also demonstrated by direct spectral characterization of (1)O(2) monomol light emission in the near-infrared region (lambda = 1270 nm). In summary, our studies demonstrated that LOOH can originate (1)O(2). The experimental evidences indicate that (1)O(2) is generated at a yield close to 10% by the Russell mechanism, where a linear tetraoxide intermediate is formed in the combination of two peroxyl radicals. In addition to LOOH, other biological hydroperoxides, including hydroperoxides formed in proteins and nucleic acids, may also participate in reactions leading to the generation (1)O(2). This hypothesis is currently being investigated in our laboratory. 相似文献
84.
Biological aspects of the caterpillar Macrosoma tipulata Hübner and its damage to young leaves of Theobroma grandiflorum (Wild ex Spreng Schum) were studied under laboratory conditions of 24.5 +/- 0.7 masculineC, UR 61.6 +/- 9.1% and 12h photophase. The larval stage presented five instars with a total duration of 15.9 +/- 4.31 days, and survival of 98%. The pupal period stage was 7.0 +/- 0.56 days for males and 6.9 +/- 0.56 days for females, with 99% survival for both sex. The pupal mean length was 18.9 +/- 0.89 mm for males and 19.1 +/- 1.13 mm for females. The mean longevity of the adult was 10.3 +/- 2.25 days. The vertical distribution of damage was relatively uniform, with a tendency of greater defoliation in the middle of the treetop, but without significant difference among the three positions. 相似文献
85.
Bice Avallone Claudio Agnisola Raimondo Cerciello Raffaele Panzuto Palma Simoniello Patrizia Cretì Chiara Maria Motta 《Cell biology and toxicology》2015,31(6):273-283
This report describes the alterations induced by an environmentally realistic concentration of cadmium in skeletal muscle fibre organization, composition, and function in the teleost zebrafish. Results demonstrate that the ion induces a significant quantitative and qualitative deterioration, disrupting sarcomeric pattern and altering glycoprotein composition. These events, together with a mitochondrial damage, result in a significant reduction in swimming performance. In conclusion, the evidence here collected indicate that in presence of an environmental cadmium contamination, important economic (yields in fisheries/aquaculture), consumer health (fish is an important source of proteins), and ecological (reduced fitness due to reduced swimming performance) consequences can be expected. 相似文献
86.
87.
88.
Bello C Dal Bello G Cea M Nahimana A Aubry D Garuti A Motta G Moran E Fruscione F Pronzato P Grossi F Patrone F Ballestrero A Dupuis M Sordat B Zimmermann K Loretan J Wartmann M Duchosal MA Nencioni A Vogel P 《Bioorganic & medicinal chemistry》2011,19(24):7720-7727
New derivatives of 1,4-dideoxy-1,4-imino-d-ribitol have been prepared and evaluated for their cytotoxicity on solid and haematological malignancies. 1,4-Dideoxy-5-O-[(9Z)-octadec-9-en-1-yl]-1,4-imino-d-ribitol (13, IC50 ∼2 μM) and its C18-analogues (IC50 <10 μM) are cytotoxic toward SKBR3 (breast cancer) cells. 13 also inhibits (IC50 ∼8 μM) growth of JURKAT cells. 相似文献
89.
Romano F Motta A Melino M Negro M Gavotto G Decasteli L Careddu E Bianchi C Bianchi DM Pozio E 《Parasite (Paris, France)》2011,18(1):85-87
Trichinellosis is one of the most serious foodborne parasitic zoonoses in Europe. Wild carnivorous and omnivorous hosts are the main reservoirs of Trichinella spp. nematodes in nature. In the winter of 2008-2009, an atypical clinical case of trichinellosis occurred for the consumption of pork from a wild boar (Sus scrofa) hunted in southwestern Alps in Italy. The symptomatic individual showed delayed development of oedemas in the lower limbs and eosinophilia, which appeared three months after infection. Muscle samples harboured 3.8 larvae/g, which were identified as Trichinella britovi. During the epidemiological investigation, anti-Trichinella IgG were detected in five hunters. 相似文献
90.
Daniele De Simone Lorella D’Amico Daniela Bressanin Emma Motta Tiziana Annesi 《Mycological Progress》2011,10(3):301-306
Thirteen isolates of Inonotus rickii/Ptychogaster cubensis, from different geographic provenances, were analyzed by sequencing ITS1, ITS 2 and 5,8S ribosomal RNA region. A phylogenetic
tree, also including sequences available in Genbank database, showed that the strains enclosed in this study fall into two
well-separated groups, one formed by isolates from Florida (USA) and the other one by isolates from Europe, Argentina and
China. Differences were also highlighted on the growth rate of mycelial cultures at different temperatures. In fact, although
the tested isolates generally attained the best growth at 30°C, isolates from Europe seem well adapted to higher temperatures
and went on growing at 40°C whilst the growth of isolates from Florida significantly decreased at 35°C. Since the teleomorph
I. rickii was never detected in Florida, and in this study noticeable differences were detected by analysis of ITS region, the existence
of two possible distinct species, not discriminated solely on the basis of morphological characters, could be suggested. 相似文献