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41.
Genomic restructuring was detected in newly synthesized tritordeum by molecular and cytogenetic tools. Genomic stability is expected for advanced tritordeum lines (HchHchAABB; 2n = 42) with multiple generations of self-fertilization. This study intends to confirm or decline this hypothesis by characterizing three advanced tritordeum lines and their parental species using cytogenetics, inter-simple sequence repeat (ISSR) and retrotransposon-based markers. Mitotic chromosomes of each tritordeum line were hybridized with six synthetic oligonucleotide probes using non-denaturing fluorescence in situ hybridization. Polymorphic hybridization patterns and structural rearrangements involving SSR regions were detected. The same chromosome spreads were re-hybridized with genomic DNA of Hordeum chilense Roem. et Schult. and the 45S ribosomal DNA (rDNA) sequence pTa71. These FISH experiments allowed for parental genome discrimination, identification of nucleolar chromosomes, and detection of structural rearrangements, mostly involving rDNA loci. The chromosomes bearing SSR hybridization signals and/or chromosomes involved in structural rearrangements were identified. ISSR, retrotransposon-microsatellite amplified polymorphism, inter-retrotransposon amplified polymorphism and inter-primer binding site markers evidenced genomic reshuffling in all tritordeum lines relative to their parents. Line HT28 was considered the most genetically stable. This work demonstrated that cytogenetic and molecular monitoring of tritordeum is needed, even after several self-fertilization generations, to guarantee the selection of the most stable lines for improvement and sustainable agriculture.  相似文献   
42.
The free amino acid profile of 18 samples of tronchuda cabbage ( Brassica oleracea L. var. costata DC) leaves, harvested at three different months, was determined by HPLC/UV-vis. The tronchuda cabbage leaves total free amino acid content varied from 3.3 to 14.4 g/kg fresh weight. Generally, arginine was the major compound, followed by proline, threonine, glutamine, cysteine, and glutamic acid. This study indicates that free amino acids are not similarly distributed: in external leaves, proline and arginine were the major free amino acids, while in internal ones, arginine was the main free amino acid, followed by threonine, glutamine, and cysteine. Significant differences were observed for valine, proline, arginine, leucine, cysteine, lysine, histidine, and tyrosine contents. The levels of some free amino acids were significantly affected by the collection period. In external leaves, this occurred with glutamic acid, serine, valine, leucine, cysteine, and ornithine contents, while in internal leaves, it occurred with aspartic acid, arginine, and total contents.  相似文献   
43.
The deep-sea constitutes a true unexplored frontier and a potential source of innovative drug scaffolds. Here, we present the genome sequence of two novel marine actinobacterial strains, MA3_2.13 and S07_1.15, isolated from deep-sea samples (sediments and sponge) and collected at Madeira archipelago (NE Atlantic Ocean; Portugal). The de novo assembly of both genomes was achieved using a hybrid strategy that combines short-reads (Illumina) and long-reads (PacBio) sequencing data. Phylogenetic analyses showed that strain MA3_2.13 is a new species of the Streptomyces genus, whereas strain S07_1.15 is closely related to the type strain of Streptomyces xinghaiensis. In silico analysis revealed that the total length of predicted biosynthetic gene clusters (BGCs) accounted for a high percentage of the MA3_2.13 genome, with several potential new metabolites identified. Strain S07_1.15 had, with a few exceptions, a predicted metabolic profile similar to S. xinghaiensis. In this work, we implemented a straightforward approach for generating high-quality genomes of new bacterial isolates and analyse in silico their potential to produce novel NPs. The inclusion of these in silico dereplication steps allows to minimize the rediscovery rates of traditional natural products screening methodologies and expedite the drug discovery process.  相似文献   
44.
Fish Physiology and Biochemistry - This study verified the effects of essential oils from Lippia sidoides (EOLS) and Cymbopogon citratus (EOCC) on the anesthesia of freshwater angelfish...  相似文献   
45.
ABSTRACT

Contamination of ground water as a consequence of soil leaching processes is an issue of major concern. In this context, a simulation of the soil leaching process was designed. A sequential injection (SI) method to monitor the soil leaching of iron complexes with in-line rain simulation for leachate production is described. The developed methodology comprises the SI determination of both iron(III) and 3-hydroxy-4-pyridinones iron(III) complexes, coupled to a mini soil column (mSC) for displaying in-line rain simulations. The described SI method enabled iron(III) determination within the range 2.0–35 µmol L?1, with a detection limit of 0.42 µmol L?1, and determination of iron(III) complexes in the range 1.0–45 µmol L?1. It was successfully applied to leachates from laboratory scale soil columns (LSSC), with good precision for both iron(III) and iron complexes determinations: calculated relative standard deviation (RSD) of 5% and 6%, respectively. A step further in automation and miniaturization was attained with the incorporation of a mini soil column for the in-line leachate production. The system enabled the soil leachate production and assessment in less than 5 min, including determinations in triplicate.  相似文献   
46.
Carcinus maenas is an invasive species of recognised economical and ecological importance in which mercury accumulation could be a pathway for bioamplification through food webs. Little information is available about differential accumulation between crab sexes and morphotypes. Taking this in mind, a set of different industrial discharge scenarios were investigated in 96-h laboratory experiments for assessing the accumulation of inorganic mercury from contaminated seawater into the tissues of C. maenas. Three groups of crabs (green males, green and red females) where exposed to 5, 50 and 250 ??g Hg L?1. Differences among sexes, morphotypes and tissues were detected, depending on the mercury concentration. The muscle did not show differential accumulation between sexes or morphotypes. For mercury-exposed crabs, the contaminant was accumulated preferably in the gills (more than 75%) while, in control experiments, it was in the internal organs, muscle and hepatopancreas, and gills corresponded to less than 31% of the total mercury quantified. The different tissue contamination seems dependent on the major pathway of exposure, diet or water. Mercury accumulation by the crab was a rapid process and could represent a risk for the environment only after 96 h. In a scenario of a discharge point of 250 ??g L?1, all tissues of crabs exposed would attain a very close, or even exceed the threshold concentration value for human consumption (0.5 mg kg?1).  相似文献   
47.
Despite its low prevalence, pancreatic cancer (PC) is one of the deadliest, typically characterised as silent in early stages and with a dramatically poor prognosis when in its advanced stages, commonly associated with a high degree of metastasis. Many efforts have been made in pursuing innovative therapeutical approaches, from the search for new cytotoxic drugs and other bioactive compounds, to the development of more targeted approaches, including improved drug delivery devices. Marine biotechnology has been contributing to this quest by providing new chemical leads and materials originating from different organisms. In this review, marine biodiscovery for PC is addressed, particularly regarding marine invertebrates (namely sponges, molluscs, and bryozoans), seaweeds, fungi, and bacteria. In addition, the development of biomaterials based on marine-originating compounds, particularly chitosan, fucoidan, and alginate, for the production of advanced cancer therapies, is also discussed. The key role that drug delivery can play in new cancer treatments is highlighted, as therapeutical outcomes need to be improved to give further hope to patients.  相似文献   
48.
Malt is known to have an impact on beer flavor stability mainly due to the presence of antioxidants. In this study, five barley varieties were malted at industrial and micro scale, and quality parameters of the resulting malts were measured (diastatic power, friability, beta-glucan content, antiradical power, reducing power, lipoxygenase activity, and nonenal potential) and correlated with the sensory data obtained for the corresponding fresh and forced aged beers. A statistical strategy using multiple linear regressions was applied to explore relationships between the malt chemical parameters and beer sensory data, showing antiradical power as the major contribution of malt to beer flavor stability. Additionally, the measured antiradical power, which is well correlated with the polyphenolic content, was found to be very similar for malt and barley, emphasizing the key role of barley endogenous polyphenols.  相似文献   
49.
Feline mammary carcinomas (FMC) are highly infiltrative tumours which show a strong tendency for local recurrence and metastasis. Histological type assessment of these tumours is not sufficiently discriminatory in predicting prognosis and in this study the prognostic significance of the Elston and Ellis method of histological grading was evaluated. Ninety-two feline mammary carcinomas from 84 cats were graded and 64 queens were included in a follow-up study.Grade was significantly related to tumour size (P = 0.006), clinical stage (P = 0.005), lymphovascular invasion (P < 0.0001), mitotic index (P < 0.0001), Ki67 index (P = 0.001), overall survival (P = 0.0001) and disease-free survival (P < 0.0001). Cox regression analysis identified grade as an independent prognostic factor. Multivariable analysis also showed regional lymph node metastasis and lymphovascular emboli as independent prognostic factors related to overall survival and to disease-free-survival, respectively. The study demonstrated that histological grading can be used as a prognostic factor to evaluate the biological behaviour of FMC.  相似文献   
50.
The purpose of this study was to evaluate the frequency of anti-Toxocara antibodies in sheep from Presidente Prudente, southeastern Brazil. Serum samples were obtained from 365 sheep of diverse breeds and different ages. Samples were collected at a slaughterhouse and at farms located in Presidente Prudente. Three groups of animal of different ages were evaluated according to age: Group I: between 1 and 6 months old; Group II: between 7 and 10 months old; and Group III: between 11 and 15 months old. An ELISA test was carried out to detect anti-Toxocara antibodies (IgG) using the excretory-secretory antigens of Toxocara canis (TES) larvae. In total, 183 out of 365 animals (50.1%) were positive for anti-Toxocara antibodies. The frequency of antibody detection was directly proportional to the age of the animals (p<0.0001), indicating a relationship between infection and aging. In Group III, there was a higher prevalence in females (p=0.0041). The relevance of these animals to the epidemiology of toxocariasis in pets and human should be considered.  相似文献   
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