332 research outputs found
âUm Bando de IdĂ©ias Novas na Arqueologiaâ
The aim of this paper is to discuss the articulation of the Imperial Archaeology related to knowledge and power. From this articulation some matters are raised about the relationship between the archaeological practice, the Imperial political scheme and the Evolutionism.O objetivo deste artigo Ă© o de discutir a articulação da Arqueologia Imperial com um campo de saber e de poder. A partir desta articulação, levanto algumas questĂ”es sobre as relaçÔes entre a prĂĄtica arqueolĂłgica, o projeto polĂtico Imperial e o Evolucionismo
Comparative Analysis of Viperidae Venoms Antibacterial Profile: a Short Communication for Proteomics
Bacterial infections involving multidrug-resistant strains are one of the ten leading causes of death and an important health problem in need for new antibacterial sources and agents. Herein, we tested and compared four snake venoms (Agkistrodon rhodostoma, Bothrops jararaca, B. atrox and Lachesis muta) against 10 Gram-positive and Gram-negative drug-resistant clinical bacteria strains to identify them as new sources of potential antibacterial molecules. Our data revealed that, as efficient as some antibiotics currently on the market (minimal inhibitory concentration (MIC) = 1â32 ÎŒg mLâ1), A. rhodostoma and B. atrox venoms were active against Staphylococcus epidermidis and Enterococcus faecalis (MIC = 4.5 ÎŒg mLâ1), while B. jararaca inhibited S. aureus growth (MIC = 13 ÎŒg mlâ1). As genomic and proteomic technologies are improving and developing rapidly, our results suggested that A. rhodostoma, B. atrox and B. jararaca venoms and glands are feasible sources for searching antimicrobial prototypes for future design new antibiotics against drug-resistant clinical bacteria. They also point to an additional perspective to fully identify the pharmacological potential of these venoms by using different techniques
Structural dynamics and physicochemical properties of pDNA/DODAB:MO lipoplexes : effect of pH and anionic lipids in inverted non-lamellar phases versus lamellar phases
Dioctadecyldimethylammoniumbromide (DODAB):Monoolein (MO) lipoplexes have mainly been studied within the range of high molar ratios of DODAB, with noticeable transfection efficiencies in the Human Embryonic Kidney (HEK, a.k.a. 293T) cell line. In thiswork,we intend to study the effect of highMOcontent on the structure and physicochemical properties of pDNA/DODAB:MOlipoplexes to achieve some correlationwith their transfection efficiency. Static/Dynamic Light Scattering and Cryo-TEM imaging were used to characterize the size/ morphology of DNA/DODAB:MO lipoplexes at different DODAB:MO contents (2:1, 1:1, 1:2) and charge ratios (CRs) (+/â). Nile Red fluorescence emission was performed to detect changes in microviscosity, hydration and polarity of DNA/DODAB:MO systems. Lipoplexes stability at physiological pH values and in the presence of
anionic lipids was evaluated by Förster Resonance Energy Transfer (FRET). Physicochemical/structural data
were complemented with transfection studies in HEK cells using the ÎČ-galactosidase reporter gene activity
assay. This work reports the coexistence of multilamellar and non-lamellar inverted phases in MO-richer
lipoplexes (DODAB:MO 1:2 and 1:4), leading to transfection efficiencies comparable to those of multilamellar (DODAB-richer) lipoplexes, but at higher charge ratios [CR (+/â) = 6.0] and without dose-effect response. These results may be related to the structural changes of lipoplexes promoted by high MO content.FEDER (037291) through POFC â COMPETEFundação para a CiĂȘncia e a Tecnologia (FCT) - SFRH/BD/46968/2009 (PhD grant), PEst-C/BIA/UI4050/2011(CBMA), PEst-C/FIS/UI0607/2011 (CFUM)
The study of vancomycin use and its adverse reactions associated to patients of a brazilian university hospital
<p>Abstract</p> <p>Background</p> <p>Vancomycin is an antibiotic of growing importance in the treatment of hospital infections, with particular emphasis on its value in the fight against methicillin-resistant <it>Staphylococcus aureus</it>. However its usage profile must be evaluated to assure maximum benefit and minimum risk.</p> <p>Findings</p> <p>A cross-sectional retrospective study was carried out among inpatients that received vancomycin in a Brazilian quaternary hospital. The occurrence of adverse reactions reported was evaluated in medical records relating to patients taking vancomycin during a one year period. Males comprised 52% (95% CI: 41.7-60.2%) of the sample population, with a mean age of 50.6 (95% CI: 47.2-54.0) years and mean treatment period of 9.7 (95% CI: 8.0-11.5) Days. It was verified that nephrotoxicity occurred in 18.4% (95% CI: 11.3-27.5) of patients, Red man syndrome occurred in 2% (95% CI 0.2-7.2), while the occurrence of thrombocytopenia was 7.1% (95% CI: 2.9-14.2).</p> <p>Conclusions</p> <p>It may be noted that even after 50 years of use, adverse reactions associated with vancomycin continue with high frequency, presenting a public health problem, especially considering its current use in cases of multidrug resistant infections. In this context, we emphasize the importance of intensive pharmacovigilance in hospital as a surveillance tool after drug approval by the sanitary authority.</p
Characterization of a small cryptic plasmid from endophytic Pantoea agglomerans and its use in the construction of an expression vector
A circular cryptic plasmid named pPAGA (2,734 bp) was isolated from Pantoea agglomerans strain EGE6 (an endophytic bacterial isolate from eucalyptus). Sequence analysis revealed that the plasmid has a G+C content of 51% and contains four potential ORFs, 238(A), 250(B), 131(C), and 129(D) amino acids in length without homology to known proteins. The shuttle vector pLGM1 was constructed by combining the pPAGA plasmid with pGFPmut3.0 (which harbors a gene encoding green fluorescent protein, GFP), and the resulting construct was used to over-express GFP in E. coli and P. agglomerans cells. GFP production was used to monitor the colonization of strain EGE6gfp in various plant tissues by fluorescence microscopy. Analysis of EGE6gfp colonization showed that 14 days after inoculation, the strain occupied the inner tissue of Eucalyptus grandis roots, preferentially colonizing the xylem vessels of the host plants
Abnormal Protein Glycosylation and Activated PI3K/Akt/mTOR Pathway: Role in Bladder Cancer Prognosis and Targeted Therapeutics
Muscle invasive bladder cancer (MIBC, stage >= T2) is generally associated with poor prognosis, constituting the second most common cause of death among genitourinary tumours. Due to high molecular heterogeneity significant variations in the natural history and disease outcome have been observed. This has also delayed the introduction of personalized therapeutics, making advanced stage bladder cancer almost an orphan disease in terms of treatment. Altered protein glycosylation translated by the expression of the sialyl-Tn antigen (STn) and its precursor Tn as well as the activation of the PI3K/Akt/mTOR pathway are cancer-associated events that may hold potential for patient stratification and guided therapy. Therefore, a retrospective design, 96 bladder tumours of different stages (Ta, T1-T4) was screened for STn and phosphorylated forms of Akt (pAkt), mTOR (pmTOR), S6 (pS6) and PTEN, related with the activation of the PI3K/Akt/mTOR pathway. In our series the expression of Tn was residual and was not linked to stage or outcome, while STn was statically higher in MIBC when compared to non-muscle invasive tumours (p = 0.001) and associated decreased cancer-specific survival (log rank p = 0.024). Conversely, PI3K/Akt/mTOR pathway intermediates showed an equal distribution between non-muscle invasive bladder cancer (NMIBC) and MIBC and did not associate with cancer-specif survival (CSS) in any of these groups. However, the overexpression of pAKT, pmTOR and/or pS6 allowed discriminating STn-positive advanced stage bladder tumours facing worst CSS (p = 0.027). Furthermore, multivariate Cox regression analysis revealed that overexpression of PI3K/Akt/mTOR pathway proteins in STn+ MIBC was independently associated with approximately 6-fold risk of death by cancer (p = 0.039). Mice bearing advanced stage chemically-induced bladder tumours mimicking the histological and molecular nature of human tumours were then administrated with mTOR-pathway inhibitor sirolimus (rapamycin). This decreased the number of invasive lesions and, concomitantly, the expression of STn and also pS6, the downstream effector of the PI3K/Akt/mTOR pathway. In conclusion, STn was found to be marker of poor prognosis in bladder cancer and, in combination with PI3K/Akt/mTOR pathway evaluation, holds potential to improve the stratification of stage disease. Animal experiments suggest that mTOR pathway inhibition could be a potential therapeutic approach for this specific subtype of MIBC
Correlação entre teor de umidade e eficiĂȘncia energĂ©tica de resĂduos de Pinus taeda em diferentes idades
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