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531.
E.N. Borges R.C. Silva D.O. Futino C.M.C. Rocha-Junior C.A. Amorim S.N. Bo C.M. Lucci 《Cryobiology》2009,59(2):195-200
The present study aimed to test different cryoprotectants on cryopreservation of pig ovarian tissue. Pig ovaries (n = 3) were collected at a local slaughterhouse. From each ovary, ten cortex samples were taken. One was immediately fixed (control) and another placed in short-term tissue incubation (STTI control). The other 8 samples were cryopreserved, in pairs, using 4 different cryoprotectants: dimethyl sulphoxide (Me2SO – 1.5 M), ethylene glycol (EG – 1.5 M), propanediol (PROH – 1.5 M) and glycerol (GLY – 10%), all with 0.4% sucrose. Samples were slow cooled and stored in liquid nitrogen for 7 days. After thawing and cryoprotectant removal, one sample from each treatment was immediately fixed and the other was placed in short-term tissue incubation (STTI) for 2 h and then fixed. Samples were processed for histology and transmission electron microscopy. The percentages of morphologically normal follicles (MNF) in cryopreserved tissue using Me2SO (67.0 ± 4.9), EG (81.8 ± 1.4) and PROH (55.9 ± 9.9) were significantly lower (P < 0.05) than observed in fresh control tissue (97.7 ± 1.2). When ovarian tissue was cryopreserved with GLY, no morphologically normal follicles could be found (0%). After STTI, PROH showed a significantly lower percentage of MNF when compared with all other treatments and the control. After ultrastructural analysis, follicles cryopreserved with Me2SO and EG showed some small alterations, but no signs of advanced degeneration. Overall, these were similar to follicles from the control group. In conclusion, it is possible to cryopreserve preantral follicles from pig ovarian tissue using Me2SO or EG. 相似文献
532.
Dalton de Souza Amorim Sarah Siqueira Oliveira Daniel Dias Dornelas do Carmo Guilherme Cunha Ribeiro 《Cladistics : the international journal of the Willi Hennig Society》2023,39(1):43-57
A fossil Mycetophilidae from the Aptian Crato Formation—Cretomanota gondwanica gen. nov., sp. nov.—is described, which is the first mycetophilid from the Crato Formation and corresponds to the oldest known fossil leiine and only the second Gondwanan fossil mycetophilid described so far. Cretomanota gondwanica and both species of Alavamanota Blagoderov and Arillo were added as terminals to the data matrix of a general phylogenetic analysis of the Mycetophilidae, and both fit into the Leiinae. Alavamanota is monophyletic, sister to the clade composed by Cretomanota and the extant genus Manota Williston. The biology of the extant members of this fungivorous family corroborates the reconstruction of the Crato palaeoenvironment as including woodlands with humid habitats and microhabitats. The presence of a Cretaceous member of the tribe Manotini at low latitudes in South America reinforces the hypothesis that the clade with all manotines except Leiella Edwards corresponds to a Lower Cretaceous offshoot from a group in southern Gondwana expanding its distribution to more northern areas into the Gondwana and into Laurasia. 相似文献
533.
R. B. Noleto A. P. Amorim M. R. Vicari R. F. Artoni M. M. Cestari 《Journal of fish biology》2009,75(2):448-453
Characidium fishes with a sex chromosome system form a monophyletic group. This work presents data of Characidium lanei from the South Atlantic basin (Brazil), including an unknown type of ZW sex chromosome system for the groups including the presence of rDNA sites on sex chromosomes. 相似文献
534.
535.
L. Manco M. J. Trovoada A. Abade A. Amorim 《International Journal of Anthropology》1999,14(4):255-258
The genetic polymorphism of AMY2 was studied in the population of S. Tomé and Príncipe (West Africa) using agarose gel electrophoresis.
AMY2 frequencies are reported for the first time in a subSaharian population. The gene frequencies found were: AMY2*1=0.948,
AMY2*3=0.052 (N=173). 相似文献
536.
The overexpression of a single oncogene (ERBB2/HER2) alters the proteomic landscape of extracellular vesicles
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ERBB2/HER2 amplification activates signaling cascades that lead to a tumor cell phenotype. However, despite its remarkable importance in oncology, the consequences of HER2 amplification over the extracellular vesicles (EVs) content have not yet been investigated. Here, we isolated EVs secreted by HB4a, a mammary luminal epithelial cell line and C5.2, its HER2‐overexpressing clone. We isolated two EV sets (20 and 100 K) by ultracentrifugation and used electron microscopy and nanoparticle tracking analysis for their morphological characterization. We employed GeLC‐MS/MS combined with isotope‐coded protein labeling to evaluate cell‐derived proteins and LC‐MS/MS label free spectral counting to quantify the EVs proteome. We found higher HER2 levels in both C5.2‐derived EVs when compared with C5.2 cells, suggesting its preferential shuttling. Proteins capable of inducing malignant transformation are enriched in both C5.2 EV subsets, including two HER2‐related proteins involved in cell motility and invasion, cofilin and CD44. MetaCore? analysis indicated an enrichment of cell adhesion and cytoskeleton‐remodeling pathways in C5.2 EVs, as well as proteins related to HER2 signaling, such as sphingosine‐1‐phosphate pathway. Together, our data indicate that in terms of protein content, distinct vesicle sets reinforce and complement each other. Our results also suggest that HER2‐upregulated proteins from EVs may be relevant for cellular malignancy and can be potential biomarkers for HER2+ cancer patients. 相似文献
537.
Leukocyte samples from 316 unrelated blood donors were screened for malic enzyme (MEM). The frequency of the common allele in this investigation was MEM1 = 0.63. There is evidence for the existence of a rare fourth allele MEM4. 相似文献
538.
The formal genetics of esterase D (EC 3.1.1.1) was studied in family data and mother/child pairs. A general agreement with mendelian expectations was found. However, a significant sex-phenotype association was detected in families from northwestern Portugal as well as in mother/child pairs and family data from southwestern Germany. 相似文献
539.
P. Amorim H. Meyr C. Almeder B. Almada-Lobo 《Flexible Services and Manufacturing Journal》2013,25(3):389-413
Managing perishability may represent a remarkable problem in supply chain management of a varied set of industries. In fact, perishability can influence, for example, productivity or customer service and it may happen to occur in one or more processes throughout the supply chain. In this paper a review on planning models that handle perishability issues in production and distribution is conducted. The contribution of this paper is three-fold. First, a new framework for classifying perishability models based on multiple process features is presented. Second, it draws the community attention to the importance of managing perishability in many different industries’ supply chains by showing its relevance and by reviewing the literature related to production and distribution planning. Finally, it points towards research opportunities so far not addressed by the research community in this challenging field. 相似文献
540.
Jorddy Neves Cruz Kauê Santana da Costa Tarcísio André Amorim de Carvalho Nelson Alberto Nascimento de Alencar 《Journal of biomolecular structure & dynamics》2020,38(5):1425-1434
AbstractCongenital adrenal hyperplasia is an inherited autosomal recessive disorder related to deficient cortisol synthesis. The deficiency of steroid 21-hydroxylase (cytochrome P450 21A2), an enzyme involved in cortisol synthesis, is responsible for ~95% of cases of congenital adrenal hyperplasia. This metabolic disease exhibits three clinical forms: salt-wasting, simple virilizing, and non-classical form, which are divided according to the degree of severity. In the present study, structural and mutational analyses were performed in order to identify the structural impact of mutations on cytochrome P450 21A2 and correlate them with patient clinical severity. The following mutations were selected: arginine-356 to tryptophan (R356W), proline-30 to leucine (P30L), isoleucine-172 to asparagine (I172N), valine-281 to leucine (V281L), and the null mutation glutamine-318 (Q318X). Our computational approach mapped the location of residues on P450 and identified their implications on enzyme electrostatic potential mapping to progesterone and heme binding pockets. Using molecular dynamics simulations, we analyzed the structural stability of ligand binding and protein structure, as well as possible conformational changes at the catalytic pocket that leads to impairment of enzymatic activity. Our study sheds light on the impact structural mutations have over steroid 21-hydroxylase structure-function in the cell.Communicated by Ramaswamy H. Sarma 相似文献