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231.
Priscila Di Paula Bessa Santana Thiago Velasco Guimarães Silva Nathália Nogueira da Costa Bruno Barauna da Silva Timothy Frederick Carter Marcela da Silva Cordeiro Bruno José Martins da Silva Simone do Socorro Damasceno Santos Anderson Manoel Herculano Paulo Roberto Adona Otávio Mitio Ohashi Moysés dos Santos Miranda 《Molecular reproduction and development》2014,81(10):918-927
232.
Guilherme G. Naves André F. Silva Uri Antebi Priscila C. Cristovam Emerson K. Honda Rodrigo P. Guimarães 《Cell and tissue banking》2018,19(4):659-666
Tissue Banks have become the main source for bone grafts, due to preference for homologous tissues. Notwithstanding the use of aseptic techniques for procurement of tissues and judicious selection of donors, microorganisms are frequently found in procured bones. Purpose of this study is to evaluate the factors that increase safety of procurement and minimize discard of procured tissues. Microbiological contamination was analyzed in 1271 musculoskeletal tissues removed from 138 multi-organ donors over a period extending from 2006 to 2016. Effects of various risk factors related with contamination were estimated using a logistic regression model. Microbiological contamination rate in the tissues was 17.1%; low pathogenic microorganisms were cultivated in 12.9% of the tissues, while highly pathogenic ones were cultivated in 4.2% of the tissues. Evolution of one single team was monitored during that period, verifying a fall in the general contamination level from 22.5 to 9.2%. Absence of antibiotics increased low pathogenic contamination risk. Every additional day in intensive care unit (ICU) increased the risk of highly pathogenic contamination. Time elapsed between death and the beginning of removal procedures was found to be relevant for both low pathogenic and highly pathogenic microorganisms. Among the studied factors, the following contributed for a significant increase in contamination by microorganisms in removed tissues: lack of use of prophylactic antibiotic therapy in donors, quantity of removed tissues, length of admission in ICU and the time elapsed between aortic clamping and beginning of the removal procedure. 相似文献
233.
Milton Artur Ruiz Roberto Luiz Kaiser Junior Lilian Piron-Ruiz Tatiana Pe?a-Arciniegas Priscila Samara Saran Luiz Gustavo De Quadros 《World journal of stem cells》2018,(10)
Crohn's disease(CD) is an inflammatory bowel disease that can affect any site of the digestive system. It occurs due to an immunological imbalance and is responsible for intestinal mucosal lesions and complications such as fistulas and stenoses. Treatment aims to stabilize the disease, reducing the symptoms and healing intestinal lesions. Surgical procedures are common in patients. Cell therapy was initially used to treat this disease in patients who also suffered from lymphoma and leukemia and were considered to be good candidates for autologous and allogeneic transplantation. After transplantation, an improvement was also observed in their CD. In 2003, the procedure began to be used to treat the disease itself, and several case series and randomized studies have been published since then; this approach currently comprises a new option in the treatment of CD. However, considerable doubt along with significant gaps in our knowledge continue to exist in relation to cell therapy for CD. Cell therapy is currently restricted to the autologous modality of hematopoietic stem cell transplantation and, experimentally, to mesenchymal stromal cells to directly treat lesions of the anal mucosa. This article presents the supporting claims for transplantation as well as aspects related to the mobilization regime, conditioning and perspectives of cell therapy. 相似文献
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235.
Genetic Diversity and Structure of Populations of Annona crassiflora Mart. of Brazilian Savanna and Its Association with Chemical Variability 下载免费PDF全文
Anary Priscila Monteiro Egydio‐Brandão Claudia Maria Furlan Déborah Yara Alves Cursino dos Santos 《化学与生物多样性》2016,13(8):990-997
Annona crassiflora Mart . is a native tree from Brazilian savanna. Isoquinoline alkaloids are characteristic of species of Annonaceae. This work aimed to assess the magnitude of genetic diversity among different populations of A. crassiflora using AFLP markers, and verify the existence of any correlation between the AFLP data and previous reported alkaloid composition. A. crassiflora from eight populations in the states of São Paulo, Goiás, Minas Gerais, and Distrito Federal were analyzed. The data suggest a low, moderate, and high level of genetic diversity from different populations of A. crassiflora. Concentration of alkaloids was significantly correlated with AFLP data, suggesting interaction between chemical and molecular markers in A. crassiflora. The data of association between the chemical and genetic differentiation of A. crassiflora may be useful to establish cultivation areas allowing the definition of strategies to preserve their genetic diversity with an interest in specific chemotypes for genetic improvement programs focused on sustainable utilization of this specie. 相似文献
236.
Cloxacillin control of experimental arthritis induced by SEC+ Staphylococcus aureus is associated with downmodulation of local and systemic cytokines 下载免费PDF全文
Priscila Maria Colavite Larissa Lumi Watanabe Ishikawa Sofia Fernanda Gonçalves Zorzella‐Pezavento Larissa Ragozo Cardoso de Oliveira Thaís Graziela Donegá França Larissa Camargo da Rosa Fernanda Chiuso‐Minicucci Andreia Espíndola Vieira Carolina Fávaro Francisconi Maria de Lourdes Ribeiro de Souza da Cunha Gustavo Pompermaier Garlet Alexandrina Sartori 《Cellular microbiology》2016,18(7):998-1008
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238.
Prion protein complexed to N2a cellular RNAs through its N-terminal domain forms aggregates and is toxic to murine neuroblastoma cells 总被引:1,自引:0,他引:1
Gomes MP Millen TA Ferreira PS e Silva NL Vieira TC Almeida MS Silva JL Cordeiro Y 《The Journal of biological chemistry》2008,283(28):19616-19625
Conversion of the cellular prion protein (PrP(C)) into its altered conformation, PrP(Sc), is believed to be the major cause of prion diseases. Although PrP is the only identified agent for these diseases, there is increasing evidence that other molecules can modulate the conversion. We have found that interaction of PrP with double-stranded DNA leads to a protein with higher beta-sheet content and characteristics similar to those of PrP(Sc). RNA molecules can also interact with PrP and potentially modulate PrP(C) to PrP(Sc) conversion or even bind differentially to both PrP isoforms. Here, we investigated the interaction of recombinant murine PrP with synthetic RNA sequences and with total RNA extracted from cultured neuroblastoma cells (N2aRNA). We found that PrP interacts with N2aRNA with nanomolar affinity, aggregates upon this interaction, and forms species partially resistant to proteolysis. RNA does not bind to N-terminal deletion mutants of PrP, indicating that the N-terminal region is important for this process. Cell viability assays showed that only the N2aRNA extract induces PrP-RNA aggregates that can alter the homeostasis of cultured cells. Small RNAs bound to PrP give rise to nontoxic small oligomers. Nuclear magnetic resonance measurements of the PrP-RNA complex revealed structural changes in PrP, but most of its native fold is maintained. These results indicate that there is selectivity in the species generated by interaction with different molecules of RNA. The catalytic effect of RNA on the PrP(C)-->PrP(Sc) conversion depends on the RNA sequence, and small RNA molecules may exert a protective effect. 相似文献
239.
240.
Kaio Cesar Chaboli Alevi Priscila Pasqüetto Mendonça Nathália Paiva Pereira João Aristeu da Rosa Maria Tercília Vilela de Azeredo Oliveira 《Invertebrate reproduction & development.》2014,58(1):9-12
The species Triatoma melanocephala and T. vitticeps are vectors of Chagas disease in Brazil. An analysis of the number of chromosomes has led to the proposal of the exclusion of both these species and T. tibiamaculata from the Brasiliensis subcomplex because of their similarities to the triatomines of North America. T. melanocephala has been found to have morphologic characteristics that are very similar to those of T. vitticeps, and these species have been considered synonymous. Thus, this paper analyzes the spermiogenesis of T. melanocephala and T. vitticeps in order to compare the two and to evaluate another possible relationship between the species. This study describes spermatogenesis and observes the morphology, cell size, and cytogenetic characteristics of triatomines. In all T. melanocephala cells, a slightly prominent peripheral heteropyknotic filament was observed. In T. vitticeps, an extensive peripheral heteropyknotic filament was observed in spermatids. This filament was observed in either the periphery or the middle of the cell. Thus, this paper describes the spermiogenesis stage of two cryptic species of triatomines and suggests that the central heteropyknotic filament can be used as a tool in the diagnosis of T. vitticeps as a vector of Chagas disease. 相似文献