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1.
Extraction of Dictyonema glabratum with hot 2% (w/v) aqueous KOH at 100 degrees C, followed by neutralisation and freeze-thawing, gave an insoluble glucan. The residue was further extracted by a similar process, but with hot 10% (w/v) aqueous KOH, furnishing a mixture of glucan, mannan and xylan. The mannan and xylan were obtained via precipitation of its copper complex with Fehling's solution, leaving the glucan in the supernatant. The insoluble complex was finally purified through gel permeation chromatography. Methylation analysis, one- and two-dimensional nuclear magnetic resonance examination showed the polysaccharides to be a (1-->3)-linked alpha-glucan (pseudonigeran) and a (1-->4)-linked beta-xylan, both not previously encountered in lichens, and a newly discovered (1-->6)-linked beta-mannan. 相似文献
2.
Joo Paulo L. F. Guilherme Edit Bosnyk Ekaterina A. Semenova Mrta Szmodis Annamria Griff kos Mra Gbor Almsi Emese Trjer Anna Udvardy Elena S. Kostryukova Oleg V. Borisov Andrey K. Larin Liliya B. Andryushchenko Egor B. Akimov Edward V. Generozov Ildus I. Ahmetov Mikls Tth Antonio H. Lancha Junior 《Biology of sport / Institute of Sport》2021,38(3):465
The purpose of this study was to explore the association of the MCT1 gene Glu490Asp polymorphism (rs1049434) with athletic status and performance of endurance athletes. A total of 1,208 Brazilians (318 endurance athletes and 890 non-athletes) and 867 Europeans (315 endurance athletes and 552 non-athletes) were evaluated in a case–control approach. Brazilian participants were classified based on self-declared ethnicity to test whether the polymorphism was different between Caucasians and Afro-descendants. Moreover, 66 Hungarian athletes underwent an incremental test until exhaustion to assess blood lactate levels, while 46 Russian athletes had their maximum oxygen uptake ( ) compared between genotypes. In the Brazilian cohort, the major T-allele was more frequent in Caucasian top-level competitors compared to their counterparts of lower competitive level (P = 0.039), and in Afro-descendant athletes compared to non-athletes (P = 0.015). Similarly, the T-allele was more frequent in European athletes (P = 0.029). Meta-analysis of the Brazilian and European cohorts confirmed that the T-allele is over-represented in endurance athletes (OR: 1.48, P = 0.03), especially when Afro-descendant athletes were included in the meta-analysis (OR: 1.58, P = 0.005). Furthermore, carriers of the T/T genotype accumulated less blood lactate in response to intense effort (P < 0.01) and exhibited higher (P = 0.04). In conclusion, the Glu490Asp polymorphism was associated with endurance athletic status and performance. Our findings suggest that, although ethnic differences may exist, the presence of the major T-allele (i.e., the Glu-490 allele) favours endurance performance more than the mutant A-allele (i.e., the 490-Asp allele). 相似文献
3.
4.
Fantinatti BE Mazzuchelli J Valente GT Cabral-de-Mello DC Martins C 《Genetica》2011,139(10):1273-1282
B chromosomes are additional chromosomes widely studied in a diversity of eukaryotic groups, including fungi, plants and animals,
but their origin, evolution and possible functions are not clearly understood. To further understand the genomic content and
the evolutionary history of B chromosomes, classical and molecular cytogenetic analyses were conducted in the cichlid fish
Astatotilapia latifasciata, which harbor 1–2 B chromosomes. Through cytogenetic mapping of several probes, including transposable elements, rRNA genes,
a repeated DNA genomic fraction (C
0
t − 1 DNA), whole genome probes (comparative genomic hybridization), and BAC clones from Oreochromis niloticus, we found similarities between the B chromosome and the 1st chromosome pair and chromosomes harboring rRNA genes. Based on
the cytogenetic mapping data, we suggest the B chromosome may have evolved from a small chromosomal fragment followed by the
invasion of the proto-B chromosome by several repeated DNA families. 相似文献
5.
Marina Yazigi Solis Simon Cooper Ruth M Hobson Guilherme G. Artioli Maria C. Otaduy Hamilton Roschel Jacques Robertson Daniel Martin Vitor S. Painelli Roger C. Harris Bruno Gualano Craig Sale 《PloS one》2015,10(4)
Objectives
Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2).Methods
In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen trained male cyclists completed four 20-Km cycling time trials (two pre supplementation and two post supplementation), with a battery of cognitive function tests (Stroop test, Sternberg paradigm, Rapid Visual Information Processing task) being performed before and after exercise on each occasion.Results
In Study 1, there were no within-group effects of beta-alanine supplementation on brain homocarnosine/carnosine signal in either vegetarians (p = 0.99) or omnivores (p = 0.27); nor was there any effect when data from both groups were pooled (p = 0.19). Similarly, there was no group by time interaction for brain homocarnosine/carnosine signal (p = 0.27). In study 2, exercise improved cognitive function across all tests (P<0.05), although there was no effect (P>0.05) of beta-alanine supplementation on response times or accuracy for the Stroop test, Sternberg paradigm or RVIP task at rest or after exercise.Conclusion
28 d of beta-alanine supplementation at 6.4g d-1 appeared not to influence brain homocarnosine/carnosine signal in either omnivores or vegetarians; nor did it influence cognitive function before or after exercise in trained cyclists. 相似文献6.
Kurek KC Luks VL Ayturk UM Alomari AI Fishman SJ Spencer SA Mulliken JB Bowen ME Yamamoto GL Kozakewich HP Warman ML 《American journal of human genetics》2012,90(6):1108-1115
Congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies (CLOVES) is a sporadically occurring, nonhereditary disorder characterized by asymmetric somatic hypertrophy and anomalies in multiple organs. We hypothesized that CLOVES syndrome would be caused by a somatic mutation arising during early embryonic development. Therefore, we employed massively parallel sequencing to search for somatic mosaic mutations in fresh, frozen, or fixed archival tissue from six affected individuals. We identified mutations in PIK3CA in all six individuals, and mutant allele frequencies ranged from 3% to 30% in affected tissue from multiple embryonic lineages. Interestingly, these same mutations have been identified in cancer cells, in which they increase phosphoinositide-3-kinase activity. We conclude that CLOVES is caused by postzygotic activating mutations in PIK3CA. The application of similar sequencing strategies will probably identify additional genetic causes for sporadically occurring, nonheritable malformations. 相似文献
7.
Reis RA Iacomini M Gorin PA de Souza LM Grube M Cordeiro LM Sassaki GL 《FEMS microbiology letters》2005,249(1):1-6
Fatty acid components, in both the free and combined form of the intact tropical lichen Teloschistes flavicans, and its isolated photobiont and mycobiont, were analyzed by GC-MS of derived methyl esters. Its rDNA analysis confirmed that the isolated cultured symbionts belong to the genera Trebouxia and Teloschistes, respectively. The fatty acid composition of the lichen did not correspond to those found in the isolated symbionts, suggesting that the fatty acid metabolism is markedly influenced by the symbiosis. Differences in the fatty acid composition in the lichen were observed during the summer (27 degrees C), when the main fatty acids were saturated and in the winter (22 degrees C) when an increase of unsaturated fatty acids occurred. Similar differences of composition were also observed for the cultured mycobiont at different temperatures. The increase in the unsaturation level at low temperatures would maintain the membrane fluidity. Our results are the first on the fatty acids of a tropical lichen and suggest that it is sensitive to small temperature variations, which influences its saturated and unsaturated fatty acid composition. 相似文献
8.
Guilherme Rocha Melo Gondim Fabiana Baroni Alves Makdissi Ricardo Cesar Fogaroli Juan Bautista Donoso Collins Hirofumi Iyeyasu Douglas Guedes de Castro Maria Letícia Gobo Silva Michael Jenwei Chen Tharcisio Machado Coelho Henderson Ramos Antônio Cássio Assis Pellizzon 《Reports of Practical Oncology and Radiotherapy》2019,24(6):551-555
BackgroundWhole breast irradiation reduces loco-regional recurrence and risk of death in patients submitted to breast-conserving treatment. Data show that radiation to the index quadrant alone may be enough in selected patients.AimTo report the experience with intra-operative radiotherapy (IORT) with Electron-beam Cone in Linear Accelerator (ELIOT) and the results in overall survival, local control and late toxicity of patients submitted to this treatment.Materials and Methods147 patients treated with a median follow up of 6.9 years (0.1?11.5 years). The actuarial local control and overall survival probabilities were estimated using the Kaplan Meier method. All tests were two-sided and p ? 0.05 was considered statistically significant.ResultsOverall survival of the cohort in 5 years, in the median follow up and in 10 years was of 98.3%, 95.1% and 95.1%, respectively, whereas local control in 5 years, in the median follow up and in 10 years was of 96%, 94.9% and 89.5%, respectively. Two risk groups were identified for local recurrence depending on the estrogen or progesterone receptors, axillary or margin status and lymphovascular invasion (LVI) (p = 0.016).ConclusionsIORT is a safe and effective treatment. Rigorous selection is important to achieve excellent local control results. 相似文献
9.
Guilherme S. T. Garbino 《Cladistics : the international journal of the Willi Hennig Society》2015,31(6):652-678
The marmosets, tribe Callitrichini, are the most speciose clade in the subfamily Callitrichinae, containing 21 species. However, there is no consensus among molecular and morphological systematists as to how many genera should be recognized for the group. To test the morphological support for the alternative generic classifications, this study presents a comprehensive phylogenetic analysis. It is the first such analysis to include all 21 species and employ continuous and discrete osteological, pelage and tegument, karyological and vocal characters. This dataset was combined with nucleotide sequences from two mitochondrial and four nuclear regions. Separate analyses showed that, among morphological datasets, osteological characters were best at solving relationships at more inclusive levels, whilst pelage characters were most informative at the interspecific level. This suggests the presence of different transformation rates for the two character sets. When a single most parsimonious tree was obtained using the 83‐character matrix, three main clades were identified, supporting the division of the marmosets into three genera: Callithrix, Cebuella and Mico. The total evidence analysis that included an additional 3481 molecular characters corroborated most of the morphology‐based clades and also supported a three‐genus classification of the marmosets. This is the first morphological study to support an Amazonian marmoset clade (Cebuella + Mico), which is also strongly supported in exclusively molecular phylogenies, and to synonimize Callibella under Mico. 相似文献
10.
Marcelo Piaia Carolina Bonet Bub Guilherme de Menezes Succi Margareth Torres Thiago Henrique Costa Fabricio Costa Pinheiro Marcelo Henrique Napimoga 《Cell and tissue banking》2017,18(1):75-81
According to the Brazilian Association of Organ Transplants, in 2015, 19,408 bone transplants were performed in Brazil, over 90% by Dental Surgeons. The surgical technique itself has a respectable number of reports regarding its clinical efficacy, as measured by long-term survival of dental implants in grafted areas. Uncertainty remains, however, as to whether fresh frozen grafts from human bone donors remain immunologically innocuous in the body of the host. Six male with no previous medical history of note, including systemic diseases, surgery or blood transfusion were selected. These patients underwent reconstructive procedures (sinus lifting) using fresh frozen human bone from a tissue bank. All patients had venous blood samples collected prior to surgery and 6 months after the procedure. Anti-HLA analysis for the detection of HLA (human leukocyte antigen) antibodies was performed using methods such as the LABScreen PRA Class I and Class II, LABScreen Single Antigen Class I and Class II, Luminex Platform. Reactive individuals to the screening tests (LABScreen PRA) were further investigated to determine the specificity of the antibodies detected (LABScreen Single Antigen) with a cutoff value of median fluorescence intensity ≥500. As a result, it was observed that two patients (33%) were positive in screening tests, one presenting with anti-HLA Class I and II sensitization and the other with anti-HLA class II. The specificity analysis showed that the patients sensitized to HLA class II presented 4 specificities, 3 of which immunologically relevant. In the second individual, 23 specificities were identified, 6 of which immunologically important for HLA class I and 4 specificities for HLA class II, 3 of these were immunologically important. All specificities detected had average fluorescence. These findings are suggestive that sinus-lifting procedures with allogeneic bone can induce immunological sensitization. 相似文献