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41.
42.
First Epidemiologic Study in Argentina of the Prevalence of BK Viruria in Kidney Transplant Patients
R. Schiavelli R. Bonaventura M.C. Rial H. Petrone G. Soler Pujol L.J. Gaite M. Acosta A. Gutierrez F. Acosta G. Valdez P. Raffaele G. Chanta M. Perez L. Potes E. Suso G. Cremades J. Ibañez N. Imperiali M.C. Freire 《Transplantation proceedings》2014,46(9):3010-3014
BackgroundThe worldwide seroprevalence of human BK polyomavirus (BKV) in adults is 80%. About 10%–60% of renal transplant recipients experience BKV infection, nephropathy of the graft may occur in 5% of the cases, and up to 45% lose the graft. The aim of this work was to describe the prevalence of BK viruria during the 1st year after transplantation.MethodsAn epidemiologic multicenter cross-sectional study was carried out in consecutive patients at each site with kidney transplantation from August 2011 to July 2012. Clinically significant viruria was defined as >107 copies/mL. Viral DNA was extracted with the use of silica columns. Quantification was performed with the use of real-time polymerase chain reaction with primers that amplify a fragment of the large T-antigen gene and with a specific Taqman-MGB probe for BKV. For each assay, a standard curve with a quantified plasmid was included.ResultsOf 402 renal transplant recipients at 18 renal transplant sites, we analyzed 382; median age was 46.33 years, and 46.40% were female. The median of the temporal distribution for urine samples was 153 days. BK virus was detected in 50/382 samples (13%), 18 with values >107 copies/mL (4.7%). The median of the distribution of positive values was 123 days and the highest frequency of positive values was in months 3–7. The conditions of recipient older than 34 years and donor older than 41 years were the only ones that showed statistically significant association with BK viruria. No association with any specific immunosuppressive drug was observed.ConclusionsThis is the first multicenter study conducted in Argentina to determine the prevalence of BK viruria in renal transplant recipients. Because of the growing number of the population susceptible to this infection, it is important to register and describe data about its epidemiology and associated risk factors. 相似文献
43.
Vinícius Rafael Funck Leandro Rodrigo Ribeiro Letícia Meier Pereira Clarissa Vasconcelos de Oliveira Jéssica Grigoletto Michele Rechia Fighera Luiz Fernando Freire Royes Ana Flávia Furian Mauro Schneider Oliveira 《Epilepsy research》2014,108(10):1705-1710
Temporal lobe epilepsy (TLE) is the most common type of epilepsy with about one third of TLE patients being refractory to antiepileptic drugs. Knowledge about the mechanisms underlying seizure activity is fundamental to the discovery of new drug targets. Brain Na+,K+-ATPase activity contributes to the maintenance of the electrochemical gradients underlying neuronal resting and action potentials as well as the uptake and release of neurotransmitters. In the present study we tested the hypothesis that decreased Na+,K+-ATPase activity is associated with changes in the alpha subunit phosphorylation and/or redox state. Activity of Na+,K+-ATPase decreased in the hippocampus of C57BL/6 mice 60 days after pilocarpine-induced status epilepticus (SE). In addition, the Michaelis–Menten constant for ATP of α2/3 isoforms increased at the same time point. Nitration of the α subunit may underlie decreased Na+,K+-ATPase activity, however no changes in expression or phosphorylation state at Ser943 were found. Further studies are necessary define the potential of nitrated Na+,K+-ATPase as a new therapeutic target for seizure disorders. 相似文献
44.
JL Adams M Murray N Patel MT Sawkin RC Boardman C Pham H Kaur D Patel JL Yager L Pontiggia J Baxter 《HIV medicine》2021,22(1):28-36
45.
Pedro Ferreira Brbara Abreu Cristina Freire Diana M. Fernandes Eduardo F. Marques 《Materials》2021,14(4)
Fuel cells are emerging devices as clean and renewable energy sources, provided their efficiency is increased. In this work, we prepared nanocomposites based on multiwalled carbon nanotubes (MWNTs) and transition metal dichalcogenides (TMDs), namely WS2 and MoS2, and evaluated their performance as electrocatalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), relevant to fuel cells. The one- and two-dimensional (1D and 2D) building blocks were initially exfoliated and non-covalently functionalized by surfactants of opposite charge in aqueous media (tetradecyltrimethylammonium bromide, TTAB, for the nanotubes and sodium cholate, SC, for the dichalcogenides), and thereafter, the three-dimensional (3D) MoS2@MWNT and WS2@MWNT composites were assembled via surfactant-mediated electrostatic interactions. The nanocomposites were characterized by scanning electron microscopy (SEM) and structural differences were found. WS2@MWNT and MoS2@MWNT show moderate ORR performance with potential onsets of 0.71 and 0.73 V vs. RHE respectively, and diffusion-limiting current densities of −1.87 and −2.74 mA·cm−2, respectively. Both materials present, however, better tolerance to methanol crossover when compared to Pt/C and good stability. Regarding OER performance, MoS2@MWNT exhibits promising results, with η10 and jmax of 0.55 V and 17.96 mA·cm−2, respectively. The fabrication method presented here is cost-effective, robust and versatile, opening the doors for the optimization of electrocatalysts’ performance. 相似文献
46.
Antonio S Andrade Filho Aristidez C Queiroz Antonio C C Freire Leonardo Conrado S Lima Celso A S Filho Isolda N Amado Mittermeyer G Reis Isis Fernandes Magalh?es Theomira M A Carmo 《The Brazilian journal of infectious diseases》2007,11(4):435-438
Central nervous system (CSN) involvement in schistosomiasis is an ectopic manifestation with a large variety of clinical forms, including pseudotumoral, which occurs in isolated cases and is rare. Three patients with epidemiological indications of this pathology were examined; the clinical picture included lower-back pain irradiating to lower limbs, associated with progressive flaccid paraparesis and sphincterial disturbances in cases in which the spinal chord was involved; while in cases with encephalitic impairment, headache, dizziness and cerebellar syndrome, characterized by dysarthria and right-side dysgraphia, were present. Magnetic resonance imaging (MRI) showed a growing process in all cases; cerebrospinal fluid (CSF) characteristics and biological markers were compatible with neuroschistosomiasis (NS). Biopsy of the lesions confirmed this diagnosis in one case. After specific treatment with schistosomicides and corticosteroids, clinical, radiological and laboratorial improvement was observed. 相似文献
47.
Celi Marques-Santos Walkiria Samuel Avila Regina Coeli Marques de Carvalho Alexandre Jorge Gomes de Lucena Claudia Maria Vilas Freire Elizabeth Regina Giunco Alexandre Felipe Favorette Campanharo Maria Alayde Mendona R. Rivera Maria Elizabeth Navegantes Caetano Costa Marildes Luiza de Castro 《Arquivos brasileiros de cardiologia》2020,115(5):975
48.
Ingrid de Souza Freire Ana Luisa Miranda-Vilela Lilian Carla Pereira Barbosa Erica Soares Martins Rose Gomes Monnerat Cesar Koppe Grisolia 《Toxins》2014,6(10):2872-2885
The insecticidal properties of Cry-endotoxins from Bacillus thuringiensis (Bt) have long been used as spore-crystals in commercial spray formulations for insect control. Recently, some Bt-endotoxin genes have been cloned in many different plants. Toxicological evaluations of three spore-crystal endotoxins, BtCry1Ia, BtCry10Aa and BtCry1Ba6 from B. thuringiensis, were carried out on mice to understand their adverse effects on hematological systems and on genetic material. These three spore-crystals have shown toxic activity to the boll weevil, which is one of the most aggressive pests of the cotton crop. Cry1Ia, Cry10Aa and Cry1Ba6 did not increase the micronucleus frequency in the peripheral erythrocytes of mice and did not cause changes in the frequency of polychromatic erythrocytes. However, some hematologic disburbances were observed, specifically related to Cry1Ia and Cry1Ba6, respectively, for the erythroid and lymphoid lineage. Thus, although the profile of such adverse side effects can be related to their high level of exposure, which is not commonly found in the environment, results showed that these Bt spore-crystals were not harmless to mice, indicating that each spore-crystal endotoxin presents a characteristic profile of toxicity and might be investigated individually. 相似文献
49.
Virus Genes - RNA silencing and RNA decay are functionally interlaced, regulate gene expression and play a pivotal role in antiviral responses. As a counter-defensive strategy, many plant and... 相似文献
50.
Karina Morais Faria Thais Bianca Brandão Ana Carolina Prado Ribeiro Adriele Ferreira Gouvêa Vasconcellos Icaro Thiago de Carvalho Fernando Freire de Arruda Gilberto Castro Junior Vanessa Cristina Gross Oslei Paes Almeida Marcio Ajudarte Lopes Alan Roger Santos-Silva 《Journal of endodontics》2014