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951.
Jose L. D'Eramo Gustavo M. Somoza Andrea Stefano Luis F. Canosa Osvaldo Fridman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,682(2):219
The purpose of the present work was to develop a chromatographic system for the separation of five molecular forms of the gonadotropin-releasing hormone (GnRH); mammalian GnRH (mGnRH) (LHRH), salmon GnRH (sGnRH), chicken I GnRH (clGnRH), chicken II GnRH (cIIGnRH) and lamprey GnRH I (IGnRH-I). By using an ion-exchange HPLC column and isocratic elution, it was possible to separate properly the five peptides in approximately 20 min. The utility of the system in determining the GnRHs forms present in the brain of two species of vertebrates was examined. 相似文献
952.
Adenovirus type 35 (Ad35) is an important pathogen in immunosuppressed individuals such as AIDS patients and bone marrow transplant recipients. Ad35, a member of Ad subgroup B, differs with respect to pathogenic properties from the more fully characterized subgroup C Ad, such as Ad2 and Ad5. One region of human Ad which varies between subgroups and which may influence Ad pathogenesis is early region 3 (E3), a region which appears to modulate the immune response to Ad infection. In order to begin to characterize the differences between the Ad35 E3 and the E3 of other Ad, the complete DNA sequence of the Ad35 E3 promoter and coding sequence along with two flanking structural proteins, pVIII and fiber, has been determined. Ad35 contains open reading frames which are unique to the subgroup B Ad in addition to the four characterized immunoregulatory proteins encoded by the subgroup C Ad. Further evaluation of the sequence of one of these proteins, 18.5K, which is the class-I major histocompatibility complex (MHC) binding protein of 18.5 kDa, demonstrates that the amino acid sequence of this Ad2 gp19K homologue fits a proposed model of gp19K-MHC interaction. Analysis of promoter sequences demonstrates that an NF-κB site found in the subgroup C E3 promoter is absent from the Ad35 E3 promoter. In addition, the fiber genes of Ad35 and other subgroup B Ad have been shown to diverge in an unexpected way, yielding three clusters of fiber homology. 相似文献
953.
Natlia Marins Bastos Juliana Germano Ferst Rodrigo Silva Goulart Juliano Coelho da Silveira 《Animal Reproduction》2022,19(1)
The oviduct is an important reproductive structure that connects the ovary to the uterus and takes place to important events such as oocyte final maturation, fertilization and early embryonic development. Thus, gametes and embryo can be directly influenced by the oviductal microenvironment composed by epithelial cells such secretory and ciliated cells and oviductal fluid. The oviduct composition is anatomically dynamic and is under ovarian hormones control. The oviductal fluid provides protection, nourishment and transport to gametes and embryo and allows interaction to oviductal epithelial cells. All these functions together allows the oviduct to provides the ideal environment to the early reproductive events. Extracellular vesicles (EVs) are biological nanoparticles that mediates cell communication and are present at oviductal fluid and plays an important role in gametes/embryo - oviductal cells communication. This review will present the ability of the oviducts based on its dynamic and systemic changes during reproductive events, as well as the contribution of EVs in this process. 相似文献
954.
955.
Maria Florencia Tellechea Flvia S. Donaires Vinícius S. de Carvalho Brbara A. Santana Fernanda B. da Silva Raissa S. Tristo Lílian F. Moreira Aline F. de Souza Yordanka M. Armenteros Lygia V. Pereira Rodrigo T. Calado 《Cell death & disease》2022,13(4)
In acquired immune aplastic anemia (AA), pathogenic cytotoxic Th1 cells are activated and expanded, driving an immune response against the hematopoietic stem and progenitor cells (HSPCs) that provokes cell depletion and causes bone marrow failure. However, additional HSPC defects may contribute to hematopoietic failure, reflecting on disease outcomes and response to immunosuppression. Here we derived induced pluripotent stem cells (iPSCs) from peripheral blood (PB) erythroblasts obtained from patients diagnosed with immune AA using non-integrating plasmids to model the disease. Erythroblasts were harvested after hematologic response to immunosuppression was achieved. Patients were screened for germline pathogenic variants in bone marrow failure-related genes and no variant was identified. Reprogramming was equally successful for erythroblasts collected from the three immune AA patients and the three healthy subjects. However, the hematopoietic differentiation potential of AA-iPSCs was significantly reduced both quantitatively and qualitatively as compared to healthy-iPSCs, reliably recapitulating disease: differentiation appeared to be more severely affected in cells from the two patients with partial response as compared to the one patient with complete response. Telomere elongation and the telomerase machinery were preserved during reprogramming and differentiation in all AA-iPSCs. Our results indicate that iPSCs are a reliable platform to model immune AA and recapitulate clinical phenotypes. We propose that the immune attack may cause specific epigenetic changes in the HSPCs that limit adequate proliferation and differentiation.Subject terms: Anaemia, Induced pluripotent stem cells 相似文献
956.
Anelise Fernandes e Silva Thays Duarte de Oliveira Natasha vila Bertocchi Vera Lúcia da Silva Valente Edison Zefa Maríndia Depr 《Genetics and molecular biology》2022,45(2)
Karyotypes in the worldwide subfamily Oecanthinae show variations in diploid number, chromosome morphology, and sex-chromosome system. This study described the chromosome set and phylogenetic relationships of four Neotropical species, Oecanthus lineolatus, O. valensis, O. pallidus, and O. pictus. We used classical cytogenetics and Bayesian Inference for phylogenetic reconstruction, using the mitochondrial genes COI, 12S rRNA, and 16S rRNA; and analyzed the phylogenetic patterns of changes in chromosome numbers, using ChromEvol. We observed differences in chromosome number among species and two different sex-chromosome systems. Oecanthus pictus showed 2n = 21, X0♂/22, XX♀; O. lineolatus, 2n = 20, XY♂/XX♀; and O. valensis and O. pallidus, 2n = 18, XY♂/XX♀. The karyotype of Oecanthus was asymmetric, one group with large chromosomes and variation in heterochromatin distribution, and another with small acrocentric chromosomes. The phylogenetic tree recovered two main groups: one with the Palearctic species and another with species from different bioregions, but with low posterior probability. The Neotropical species grouped separately, O. valensis and O. pictus with Nearctic and Ethiopian species, and O. pallidus and O. lineolatus in another, well-supported clade. Together, the phylogenic and chromosome data suggest descending dysploidy events during the evolution of the group. Keywords: Insect, karyotype, Chromosome, Bayesian Inference, Oecanthinae 相似文献
957.
Sandra Mariza Monteiro Elsa Oliveira António Fontaínhas‐Fernandes Mário Sousa 《Journal of morphology》2010,271(5):621-633
We have studied the gill epithelium of Oreochromis niloticus using transmission electron microscopy with the particular interested relationship between cell morphology and osmotic, immunoregulatory, or other non‐regulatory functions of the gill. Pavement cells covered the filament epithelium and lamellae of gills, with filament pavement cells showing distinct features from lamellar pavement cells. The superficial layer of the filament epithelium was formed by osmoregulatory elements, the columnar mitochondria‐rich, mucous and support cells, as well as by their precursors. Light mitochondria‐rich cells were located next to lamellae. They exhibited an apical crypt with microvilli and horizontal small dense rod‐like vesicles, sealed by tight junctions to pavement cells. Dark mitochondria‐rich cells had long dense rod‐like vesicles and a small apical opening sealed by tight junctions to pavement cells. The deep layer of the filament epithelium was formed by a network of undifferentiated cells, containing neuroepithelial and myoepithelial cells, macrophage and eosinophil‐like cells and their precursors, as well as precursors of mucous cells. The lateral‐basal surface was coated by myoepithelial cells and a basal lamina. The lamellar blood lacunae was lined by pillar cells and surrounded by a basal lamina and pericytes. The data presented here support the existence of two distinct types of pavement cells, mitochondria‐rich cells, and mitochondria‐rich cells precursors, a structural role for support cells, a common origin for pavement cells and support cells, a paracrine function for neuroepithelial cells in the superficial layer, and the control of the lamellar capillary base by endocrine and contractile cells. Data further suggest that the filament superficial layer is involved in gill osmoregulation, that may interact, through pale mitochondria‐rich cells, with the deep layer and lamellae, whereas the deep layer, through immune and neuroendocrine systems, acts in the regeneration and defense of the tissue. J. Morphol. 2010. © 2010 Wiley‐Liss, Inc. 相似文献
958.
959.
Ricardo Fagundes da Rocha Marcos Roberto de Oliveira Matheus Augusto de Bittencourt Pasquali Michael Éverton Andrades Max William Soares Oliveira Guilherme Antônio Behr José Cláudio Fonseca Moreira 《Cell biochemistry and function》2010,28(3):190-196
Exercise training has been used for treatment/prevention of many cardiovascular diseases, but the mechanisms need to be clarified. Thus, our aim was to compare oxidative stress parameters between rats submitted to a swimming training and sedentary rats (control). Twelve male rats were divided into two groups: control and exercise training. The exercise training had daily 1 h swimming sessions for 8 weeks and a load (5% of its body mass) was placed in rat's tail. Thereafter the animals were killed, aorta and heart were surgically removed and blood was collected. Body mass gain, thiobarbituric acid reactive species (TBARS), carbonyl content, total reactive antioxidant potential (TRAP), total antioxidant reactivity (TAR), superoxide dismutase (SOD) activity and catalase (CAT) activity were evaluted. The trained rats showed a lower body mass gain and no modifications on heart. An increased SOD activity was observed on aorta after the training, but no changes were seen for CAT activity, which led to an increased SOD/CAT ratio. The arterial TBARS was also increased for trained rats. The decrease in TRAP in exercise training was the single modification on plasma. Our findings suggest that the increased SOD activity could play a role in vascular adaptations to exercise training. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
960.