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101.
By A. T. Silva J. M. Santos A. C. Franco M. T. Ferreira A. N. Pinheiro 《Zeitschrift fur angewandte Ichthyologie》2009,25(2):173-177
Trends in fish passage studies are increasingly moving towards a holistic approach in considering the movements of a wide range of fish species and other aquatic fauna. In this context, it is important to consider not only salmonids and other game species, but also coarse species such as cyprinids. Moreover, knowledge of their behaviour when confronted with fishways is limited, particularly their upstream movements with regard to different hydraulic configurations. To address this deficit, research was conducted in an indoor full-scale pool-type fishway to assess the cyprinid Iberian barbel Barbus bocagei (Steindachner, 1864) response to the simultaneous presence of submerged orifices and surface notches with adjustable dimensions in association with two different flow regimes over the notches, i.e. plunging and streaming. Overall, orifices (76%) were the clear choice to negotiate the fishway. When the flow was in the plunging mode, a significantly higher proportion of fish selected the orifices to move upstream, but the proportions were equal during the streaming mode. The time taken to enter the fishway differed significantly according to the chosen discharge device and was lower for submerged orifices (52 s to 35 min.). The present study identified key factors in Iberian barbel upstream movements, which provide direct applications to future fishway designs for this species. 相似文献
102.
In a study of the causes of abortion and stillbirth in a Holstein-Friesian herd, the most probable cause detected was a lethal gene transmitted through the pedigree line. Findings of this nature have already been reported both in the United States and Canada for the same line.Replacing the sires with others solved the problem, thus demonstrating a genetic etiology for abortion and stillbirth in this lineage. The differences noted in the time of fetal mortality may indicate the action of more than one gene or variable expressivity of the mutant gene.The importance of the data is discussed in terms of the elimination of genetic factors that cause fetal mortality. 相似文献
103.
Ana Sílvia Franco Pinheiro Moreira José Pires de Lemos Filho Gerhard Zotz Rosy Mary dos Santos Isaias 《Flora》2009,204(8):604-611
This study compares photosynthetic and structural features of Dichaea cogniauxiana and Epidendrum secundum leaves and roots. The diurnal titratable acidity fluctuations indicated crassulacean acid metabolism (CAM) in E. secundum leaves, associated with anatomical features like thick cuticle, large and vacuolated cells, and reduced stomata size and frequency. Roots of both species had chloroplasts in their cortical parenchyma. However, neither the roots nor D. cogniauxiana leaves did show tissue sap acidity fluctuations. This indicates C3 metabolism in these organs. This lack of oscillation of organic acids in Epidendrum roots was at odds with a CAM-like 13C ratio, suggesting that in spite of active CO2 fixation in roots during the day, the bulk of carbon is imported from the leaves. Roots of both species showed Fv/Fm, ΔF/Fm′, ETR values similar to reports from other non-foliar photosynthetic organs. Besides reducing root carbon cost, root photosynthesis may also be important by alleviating potential hypoxia, since water-saturated velamen severely impedes the gas exchange between radicular cortex. 相似文献
104.
Angélica F. Arcanjo Isabel F. LaRocque-de-Freitas Juliana Dutra B. Rocha Daniel Zamith Ana Caroline Costa-da-Silva Marise Pinheiro Nunes Fabio P. Mesquita-Santos Alexandre Morrot Alessandra A. Filardy Mario Mariano Christianne Bandeira-Melo George A. DosReis Debora Decote-Ricardo Célio Geraldo Freire-de-Lima 《PloS one》2015,10(5)
B-1 cells can be differentiated from B-2 cells because they are predominantly located in the peritoneal and pleural cavities and have distinct phenotypic patterns and activation properties. A mononuclear phagocyte derived from B-1 cells (B-1CDP) has been described. As the B-1CDP cells migrate to inflammatory/infectious sites and exhibit phagocytic capacity, the microbicidal ability of these cells was investigated using the Leishmania major infection model in vitro. The data obtained in this study demonstrate that B-1CDP cells are more susceptible to infection than peritoneal macrophages, since B-1CDP cells have a higher number of intracellular amastigotes forms and consequently release a larger number of promastigotes. Exacerbated infection by L. major required lipid bodies/PGE2 and IL-10 by B-1CDP cells. Both infection and the production of IL-10 were decreased when PGE2 production was blocked by NSAIDs. The involvement of IL-10 in this mechanism was confirmed, since B-1CDP cells from IL-10 KO mice are more competent to control L. major infection than cells from wild type mice. These findings further characterize the B-1CDP cells as an important mononuclear phagocyte that plays a previously unrecognized role in host responses to L. major infection, most likely via PGE2-driven production of IL-10. 相似文献
105.
Corinna Stefanie Weber Katrina Hainz Tekalign Deressa Helen Strandt Douglas Florindo Pinheiro Roberta Mittermair Jennifer Pizarro Pesado Josef Thalhamer Peter Hammerl Angelika Stoecklinger 《PloS one》2015,10(6)
The skin accommodates multiple dendritic cell (DC) subsets with remarkable functional diversity. Immune reactions are initiated and modulated by the triggering of DC by pathogen-associated or endogenous danger signals. In contrast to these processes, the influence of intrinsic features of protein antigens on the strength and type of immune responses is much less understood. Therefore, we investigated the involvement of distinct DC subsets in immune reactions against two structurally different model antigens, E. coli beta-galactosidase (betaGal) and chicken ovalbumin (OVA) under otherwise identical conditions. After epicutaneous administration of the respective DNA vaccines with a gene gun, wild type mice induced robust immune responses against both antigens. However, ablation of langerin+ DC almost abolished IgG1 and cytotoxic T lymphocytes against betaGal but enhanced T cell and antibody responses against OVA. We identified epidermal Langerhans cells (LC) as the subset responsible for the suppression of anti-OVA reactions and found regulatory T cells critically involved in this process. In contrast, reactions against betaGal were not affected by the selective elimination of LC, indicating that this antigen required a different langerin+ DC subset. The opposing findings obtained with OVA and betaGal vaccines were not due to immune-modulating activities of either the plasmid DNA or the antigen gene products, nor did the differential cellular localization, size or dose of the two proteins account for the opposite effects. Thus, skin-borne protein antigens may be differentially handled by distinct DC subsets, and, in this way, intrinsic features of the antigen can participate in immune modulation. 相似文献
106.
Flavia Biamonte Fabiana Zolea Andrea Bisognin Maddalena Di Sanzo Claudia Saccoman Domenica Scumaci Ilenia Aversa Mariafranca Panebianco Maria Concetta Faniello Stefania Bortoluzzi Giovanni Cuda Francesco Costanzo 《PloS one》2015,10(3)
In a previous study, we showed that the silencing of the heavy subunit (FHC) offerritin, the central iron storage molecule in the cell, is accompanied by a modification in global gene expression. In this work, we explored whether different FHC amounts might modulate miRNA expression levels in K562 cells and studied the impact of miRNAs in gene expression profile modifications. To this aim, we performed a miRNA-mRNA integrative analysis in K562 silenced for FHC (K562shFHC) comparing it with K562 transduced with scrambled RNA (K562shRNA). Four miRNAs, namely hsa-let-7g, hsa-let-7f, hsa-let-7i and hsa-miR-125b, were significantly up-regulated in silenced cells. The remarkable down-regulation of these miRNAs, following FHC expression rescue, supports a specific relation between FHC silencing and miRNA-modulation. The integration of target predictions with miRNA and gene expression profiles led to the identification of a regulatory network which includes the miRNAs up-regulated by FHC silencing, as well as91 down-regulated putative target genes. These genes were further classified in 9 networks; the highest scoring network, “Cell Death and Survival, Hematological System Development and Function, Hematopoiesis”, is composed by 18 focus molecules including RAF1 and ERK1/2. We confirmed that, following FHC silencing, ERK1/2 phosphorylation is severely impaired and that RAF1 mRNA is significantly down-regulated. Taken all together, our data indicate that, in our experimental model, FHC silencing may affect RAF1/pERK1/2 levels through the modulation of a specific set of miRNAs and add new insights in to the relationship among iron homeostasis and miRNAs. 相似文献
107.
Macrophage tumoricidal activity relies, mainly, on the release of Tumor Necrosis
Factor alpha (TNFα) and/or on reactive oxygen or nitrogen intermediates. In
the present work, we investigated the cytotoxic activity of resident peritoneal
macrophages against L929 fibrosarcoma cell line in vitro and
in vivo. Resident macrophages lysed L929 cells in a mechanism
independent of TNFα and cell-to-cell contact. The cytotoxic activity was
largely dependent on nitric oxide (NO) release since treatment with L-NAME (NOS
inhibitor) inhibited L929 cells killing. Macrophages from mice with targeted deletion
of inducible NO synthase (iNOS) together with L929 cells produced less NO and
displayed lower, but still significant, tumoricidal activity. Notably, NO production
and tumor lysis were abolished in co-cultures with macrophages deficient in
Interferon Regulatory Factor, IRF-1. Importantly, the in vitro
findings were reproduced in vivo as IRF-1 deficient animals
inoculated i.p with L929 cells were extremely susceptible to tumor growth and their
macrophages did not produce NO, while WT mice killed L929 tumor cells and their
macrophages produced high levels of NO. Our results indicate that IRF-1 is a master
regulator of bi-directional interaction between macrophages and tumor cells. Overall,
IRF-1 was essential for NO production by co-cultures and macrophage tumoricidal
activity in vitro as well as for the control of tumor growth
in vivo. 相似文献
108.
Carolina Amália Barcellos Silva Elizabeth Ferreira Martinez Ana Paula Dias Demasi Albina Altemani Jeruza Pinheiro da Silveira Bossonaro Ney Soares Araújo Vera Cavalcanti de Araújo 《Journal of cell communication and signaling》2015,9(3):255-265
During tumor invasion, benign myoepithelial cells of carcinoma ex-pleomorphic adenoma (CXPA) surround malignant epithelial cells and disappear. The mechanisms involved in the death and disappearance of these myoepithelial cells were investigated via analysis of the expression of regulatory proteins for apoptosis, autophagy and cellular senescence in an in situ in vitro model. Protein expression relating to apoptosis (Bax, Bcl-2, Survivin), autophagy (Beclin-1, LC3B) and cellular senescence (p21, p16) was evaluated using indirect immunofluorescence. β-galactosidase expression was assessed via histochemistry. Biopsies of CXPA (ex vivo) allowed immunhistochemical evaluation of p21 and p16, whilst LC3B, p21 and p16 protein expression was analyzed by western blotting. In the in vitro model, the myoepithelial cells were positive for LC3B (cytoplasm) and p21 (nucleus), whilst in vivo positivity for p21 and p16 was observed. In vitro, β-galactosidase activity increased in the myoepithelial cells over time. Western blotting analysis revealed an increased LC3B, p16 and p21 expression in the myoepithelial cells with previous contact with the malignant cells when compared with those without contact. The investigation of behavior of benign myoepithelial cells in ductal areas of CXAP revealed that the myoepithelial cells are involved in the autophagy-senescence phenotype that subsequently leads to their disappearance. 相似文献
109.
Regis Goulart Rosa Cintia Roehrig Roselaine Pinheiro de Oliveira Ju?ara Gasparetto Maccari Ana Carolina Pe?anha Ant?nio Priscylla de Souza Castro Felippe Leopoldo Dexheimer Neto Patrícia de Campos Balzano Cassiano Teixeira 《PloS one》2015,10(11)
PurposeEarly discharge from the intensive care unit (ICU) may constitute a strategy of resource consumption optimization; however, unplanned readmission of hospitalized patients to an ICU is associated with a worse outcome. We aimed to compare the effectiveness of the Stability and Workload Index for Transfer score (SWIFT), Sequential Organ Failure Assessment score (SOFA) and simplified Therapeutic Intervention Scoring System (TISS-28) in predicting unplanned ICU readmission or unexpected death in the first 48 hours after discharge from the ICU.MethodsWe conducted a prospective cohort study in a single tertiary hospital in southern Brazil. All adult patients admitted to the ICU for more than 24 hours from January 2008 to December 2009 were evaluated. SWIFT, SOFA and TISS-28 scores were calculated on the day of discharge from the ICU. A stepwise logistic regression was conducted to evaluate the effectiveness of these scores in predicting unplanned ICU readmission or unexpected death in the first 48 hours after discharge from the ICU. Moreover, we conducted a direct accuracy comparison among SWIFT, SOFA and TISS-28 scores.ResultsA total of 1,277 patients were discharged from the ICU during the study period. The rate of unplanned ICU readmission or unexpected death in the first 48 hours after discharge from the ICU was 15% (192 patients). In the multivariate analysis, age (P = 0.001), length of ICU stay (P = 0.01), cirrhosis (P = 0.03), SWIFT (P = 0.001), SOFA (P = 0.01) and TISS-28 (P<0.001) constituted predictors of unplanned ICU readmission or unexpected death. The SWIFT, SOFA and TISS-28 scores showed similar predictive accuracy (AUC values were 0.66, 0.65 and 0.74, respectively; P = 0.58).ConclusionsSWIFT, SOFA and TISS-28 on the day of discharge from the ICU have only moderate accuracy in predicting ICU readmission or death. The present study did not find any differences in accuracy among the three scores. 相似文献
110.
Mirele da Silveira Vasconcelos Neuza F Gomes-Rochette Maria Liduína M de Oliveira Diana Célia S Nunes-Pinheiro Adriana R Tomé Francisco Yuri Maia de Sousa Francisco Geraldo M Pinheiro Carlos Farley H Moura Maria Raquel A Miranda Erika Freitas Mota Dirce Fernandes de Melo 《Experimental biology and medicine (Maywood, N.J.)》2015,240(12):1648-1655
Cashew apple is a tropical pseudofruit consumed as juice due to its excellent nutritional and sensory properties. In spite of being well known for its important antioxidant properties, the cashew apple has not been thoroughly investigated for its therapeutic potential. Thereby, this study evaluated the antioxidant capacity, anti-inflammatory, and wound-healing activities of cashew apple juice. Juices from ripe and immature cashew apples were analyzed for antioxidant, anti-inflammatory, and wound-healing properties. Those were evaluated in murine models of xylene-induced ear edema and wound excision. Swiss mice were treated with cashew juice by gavage. Edema thickness was measured and skin lesions were analyzed by planimetry and histology. Both antioxidant content and total antioxidant activity were higher in ripe cashew apple juice (RCAJ) than in unripe cashew apple juice (UNCAJ). The UNCAJ presented the main anti-inflammatory activity by a significant inhibition of ear edema (66.5%) when compared to RCAJ (10%). Moreover, UNCAJ also showed the best result for wound contraction (86.31%) compared to RCAJ (67.54%). Despite of higher antioxidant capacity, RCAJ did not promote better anti-inflammatory, and healing responses, which may be explained by the fact that treatment increased antioxidants level leading to a redox “imbalance” turning down the inflammatory response modulation exerted by reactive oxygen species (ROS). The results suggest that UNCAJ presents a greater therapeutic activity due to a synergistic effect of its phytochemical components, which improve the immunological mechanisms as well as an optimal balance between ROS and antioxidants leading to a better wound healing process. 相似文献