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111.
Thayana Conceição Barbosa Bruno Almeida Lopes Caroline Barbieri Blunck Marcela Braga Mansur Adriana Vanessa Santini Deyl Mariana Emerenciano Maria S. Pombo-de-Oliveira 《BMC medical genomics》2018,11(1):122
Background
Chromosome translocations are a hallmark of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Additional genomic aberrations are also crucial in both BCP-ALL leukemogenesis and treatment management. Herein, we report the phenotypic and molecular cytogenetic characterization of an extremely rare case of BCP-ALL harboring two concomitant leukemia-associated chromosome translocations: t(1;19)(q23;q13.3) and t(9;17)(p13;q11.2). Of note, we described a new rearrangement between exon 6 of PAX5 and a 17q11.2 region, where intron 3 of SPECC1 is located. This rearrangement seems to disrupt PAX5 similarly to a PAX5 deletion. Furthermore, a distinct karyotype between diagnosis and relapse samples was observed, disclosing a complex clonal evolution during leukemia progression.Case presentation
A 16-year-old boy was admitted febrile with abdominal and joint pain. At clinical investigation, he presented with anemia, splenomegaly, low white blood cell count and 92% lymphoblast. He was diagnosed with pre-B ALL and treated according to high risk GBTLI-ALL2009. Twelve months after complete remission, he developed a relapse in consequence of a high central nervous system and bone marrow infiltration, and unfortunately died.Conclusions
To our knowledge, this is the first report of a rearrangement between PAX5 and SPECC1. The presence of TCF3-PBX1 and PAX5-rearrangement at diagnosis and relapse indicates that both might have participated in the malignant transformation disease maintenance and dismal outcome.112.
José Cavalcante Souza Vieira Camila Pereira Braga Grasieli de Oliveira Cilene do Carmo Federici Padilha Paula Martin de Moraes Luiz Fabricio Zara Aline de Lima Leite Marília Afonso Rabelo Buzalaf Pedro de Magalhães Padilha 《Biological trace element research》2018,181(1):164-172
Poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) is a water-soluble organogermanium compound that exerts various physiological effects, including anti-inflammatory activity and pain relief. In water, Ge-132 is hydrolyzed to 3-(trihydroxygermyl)propanoic acid (THGP), which in turn is capable of interacting with cis-diol compounds through its trihydroxy group, indicating that this compound could also interact with diol-containing nucleic acid constituents. In this study, we evaluated the ability of THGP to interact with nucleosides or nucleotides via nuclear magnetic resonance (NMR) analysis. In addition, we evaluated the effect of added THGP on the enzymatic activity of adenosine deaminase (ADA) when using adenosine or 2′-deoxyadenosine as a substrate. In solution, THGP indeed formed complexes with nucleotides or nucleosides through their cis-diol group. Moreover, the ability of THGP to form complexes with nucleotides was influenced by the number of phosphate groups present on the ribose moiety. Notably, THGP also inhibited the catalysis of adenosine by ADA in a concentration-dependent manner. Thus, interactions between THGP and important biological nucleic acid constituents might be implicated in the physiological effects of Ge-132. 相似文献
113.
Two Lower Liassic sections of the Banos de Alhama de Granada outcrop are studied. The Hettangian and Sinemurian ammonite assemblages are detailed and a reinterpretation of the stratigraphy of the outcrop made.The ammonites collected show a clear mediterranean character. A biostratigraphy for the Hettangian and Sinemurian can be made but the correlation with the northeuropean zonal divisions and chronostratigraphy is rather difficult. These are the only west mediterranean sections where a succession of Hettangian ammonite assemblages have been made. 相似文献
114.
The wood of Platymiscium praecox Mart. (Leguminosae-Lotoideae) contains sitosterol, 4,2′,4′-trihydroxychalcone, (2R)-7-hydroxyflavanone, (±)-7,4′-dihydroxyflavanone, (2S, 3S)-3,7-dihydroxyflavanone, 3,7-dihydroxyflavone, 3,7,4′-trihydroxyflavone, 6,7-dihydroxy-4′-methoxyisoflavone and 6,7-dimethoxycoumarin. It also contains three novel compounds: 7-hydroxy-4-methoxy-5-methylcoumarin, 7-O-glucosyloxy-4-methoxy-5-methylcoumarin and 7-hydroxy-4,8-dimethoxy-5-methylcoumarin. 相似文献
115.
Functional morphology of the male reproductive system in Callichirus major (Crustacea: Decapoda: Axiidea): Evidence of oocytes in the gonad
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Tugstênio L. Souza Adriane A. Braga Laura S. López‐Greco Erika T. Nunes 《Acta zoologica》2018,99(1):32-41
Callichirus major inhabits the intertidal region of marine ecosystems and it is frequently used as live bait for fishing. This study aimed to describe the functional anatomy of the male reproductive system by microscopic techniques. The animals were collected along the Corujão beach, Piuma—ES, Brazil, and, in laboratory, the males were classified into two phases: immature (IM) and developed (DE) based on the macroscopic characteristics of the gonads. The gonad and vas deferens were dissected for histological routine and histochemical tests. Histologically, it was noted that in both phases, the more distal region of gonads has ovarian characteristics, showing developing oocytes. Also, different male germ cells were identified: spermatogonium (SPG), spermatocytes I and II (SPTCI, SPTCII), initial and final spermatid (IS, FS) and sperm (SPZ). Accessory cells with spherical or pyramidal nuclei were also present inside the testicular lobules. According to the vas deferens structure, three regions can be characterized: proximal (PVD), middle (MVD) and distal (DVD). In the lumen of the vas deferens, a spermatophoric matrix highly reactive for histochemical tests was observed. The presence of female germ cells in males suggests the occurrence of intersexuality or hermaphroditism in this species. 相似文献
116.
Ananza M. Rabello Catherine L. Parr Antônio C. M. Queiroz Danielle L. Braga Graziele S. Santiago Carla R. Ribas 《Biotropica》2018,50(1):39-49
Changes in land use strongly influence habitat attributes (e.g., herbaceous ground cover and tree richness) and can consequently affect ecological functions. Most studies have focused on the response of these ecological functions to land‐use changes within only a single vegetation type. These studies have often focused solely on agricultural conversion of forests, making it nearly impossible to draw general conclusions across other vegetation types or with other land‐use changes (e.g., afforestation). We examined the consequences of agricultural conversion for seed removal by ants in native grassland, savanna, and savanna‐forest habitats that had been transformed to planted pastures (Brachiaria decumbens) and tree plantations (Eucalyptus spp.) and explored if changes in seed removal were correlated with differences in habitat attributes between habitat types. We found that land‐use changes affected seed removal across the tree cover gradient and that the magnitude of impact was influenced by similarity in habitat attributes between native and converted habitats, being greater where there was afforestation (Eucalyptus spp in grassland and savanna). Herbaceous ground cover, soil hardness, and tree richness were the most important habitat attributes that correlated with differences in seed removal. Our results reveal that the magnitude of impact of land‐use changes on seed removal varies depending on native vegetation type and is associated with the type of habitat attribute change. Our findings have implications for biodiversity in tropical grassy systems: afforestation can have a greater detrimental impact on ecological function than tree loss. 相似文献
117.
118.
The request for new flavourings increases every year. Consumer perception that everything natural is better is causing an increase demand for natural aroma additives. Biotechnology has become a way to get natural products. γ-Decalactone is a peach-like aroma widely used in dairy products, beverages and others food industries. In more recent years, more and more studies and industrial processes were endorsed to cost-effect this compound production. One of the best-known methods to produce γ-decalactone is from ricinoleic acid catalyzed by Yarrowia lipolytica, a generally regarded as safe status yeast. As yet, several factors affecting γ-decalactone production remain to be fully understood and optimized. In this review, we focus on the aromatic compound γ-decalactone and its production by Y. lipolytica. The metabolic pathway of lactone production and degradation are addressed. Critical analysis of novel strategies of bioprocess engineering, metabolic and genetic engineering and other strategies for the enhancement of the aroma productivity are presented. 相似文献
119.