737 research outputs found
Radiografia simples e tomografia computadorizada do crânio em crianças e adolescentes vítimas de traumatismo craniano leve
OBJECTIVE: To identify which pediatric patients with mild head trauma are candidates for skull radiographs or cranial computed tomography (CCT) scans. METHOD: Patients with mild head trauma aged from 0 to 19 years presenting to the Emergency Department of a trauma centre from Salvador City, Brazil, between May 2007 and May 2008. RESULTS: A total of 1888 mild head trauma patients were admitted; mean age was 7.4 (±5.5) years. A total of 1956 skull radiographs and 734 CCT scans were performed. About 44.4% patients with Glasgow coma score (GCS) 13 and 55.4% with GCS 14 had abnormal CCT scans. In patients with multiple traumas, 16% had abnormal findings on CCT scans. CONCLUSION: We strongly recommend routine CCT studies to patients with GCS of 13 and 14 or to multiple trauma victims, independently of score. Routine screening skull radiographs were not useful in the evaluation of mild head trauma patients in this study.OBJETIVO: Identificar quais os pacientes na faixa pediátrica com trauma craniencefálico leve são candidatos para a realização de radiografia simples ou tomografia computadorizada do crânio (TCC). MÉTODO: Pacientes com trauma craniano leve, entre 0 e 19 anos, admitidos em um centro de referência em traumatologia, na cidade do Salvador, Brasil, entre maio 2007 e maio 2008. RESULTADOS: Foram atendidos 1888 pacientes com trauma craniano leve, com idade média de 7,4 (±5,5) anos. Um total de 1956 radiografias simples e 734 TCC foram realizadas. Em 44,4% dos pacientes com escala de coma de Glasgow (GCS) 13 e 55.4% com GCS 14, tiveram TCC com achados anormais. Em pacientes com múltiplos traumas, 16% possuíam alterações na TCC. CONCLUSÃO: Recomendamos TCC em pacientes com GCS 13 e 14 ou naqueles com traumas múltiplos, independente do GCS. Radiografias simples do crânio como rotina, não foram identificadas como úteis, no presente estudo
Processing and characterization of chitosan microspheres to be used as templates for layer-by-layer assembly
Chitosan (Ch) microspheres have been developed
by precipitation method, cross-linked with glutaraldehyde
and used as a template for layer-by-layer (LBL)
deposition of two natural polyelectrolytes. Using a LBL
methodology, Ch microspheres were alternately coated with
hyaluronic acid (HA) and Ch under mild conditions. The
roughness of the Ch-based crosslinked microspheres was
characterized by atomic force microscopy (AFM). Morphological
characterization was performed by environmental
scanning electron microscopy (ESEM), scanning
electron microscopy (SEM) and stereolight microscopy.
The swelling behaviour of the microspheres demonstrated
that the ones with more bilayers presented the highest water
uptake and the uncoated cross-linked Ch microspheres
showed the lowest uptake capability. Microspheres presented
spherical shape with sizes ranging from 510 to
840 lm. ESEM demonstrated that a rougher surface with
voids is formed in multilayered microspheres caused by the
irregular stacking of the layers. A short term mechanical
stability assay was also performed, showing that the LBL
procedure with more than five bilayers of HA/Ch over Ch
cross-linked microspheres provide higher mechanical
stability
Contribution of primary motor cortex to compensatory balance reactions
<p>Abstract</p> <p>Background</p> <p>Rapid compensatory arm reactions represent important response strategies following an unexpected loss of balance. While it has been assumed that early corrective actions arise largely from sub-cortical networks, recent findings have prompted speculation about the potential role of cortical involvement. To test the idea that cortical motor regions are involved in early compensatory arm reactions, we used continuous theta burst stimulation (cTBS) to temporarily suppress the hand area of primary motor cortex (M1) in participants prior to evoking upper limb balance reactions in response to whole body perturbation. We hypothesized that following cTBS to the M1 hand area evoked EMG responses in the stimulated hand would be diminished. To isolate balance reactions to the upper limb participants were seated in an elevated tilt-chair while holding a stable handle with both hands. The chair was held vertical by a magnet and was triggered to fall backward unpredictably. To regain balance, participants used the handle to restore upright stability as quickly as possible with both hands. Muscle activity was recorded from proximal and distal muscles of both upper limbs.</p> <p>Results</p> <p>Our results revealed an impact of cTBS on the amplitude of the EMG responses in the stimulated hand muscles often manifest as inhibition in the stimulated hand. The change in EMG amplitude was specific to the target hand muscles and occasionally their homologous pairs on the non-stimulated hand with no consistent effects on the remaining more proximal arm muscles.</p> <p>Conclusions</p> <p>Present findings offer support for cortical contributions to the control of early compensatory arm reactions following whole-body perturbation.</p
2019 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations : summary from the basic life support; advanced life support; pediatric life support; neonatal life support; education, implementation, and teams; and first aid task forces
The International Liaison Committee on Resuscitation has initiated a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation science. This is the third annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. It addresses the most recent published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. This summary addresses the role of cardiac arrest centers and dispatcher-assisted cardiopulmonary resuscitation, the role of extracorporeal cardiopulmonary resuscitation in adults and children, vasopressors in adults, advanced airway interventions in adults and children, targeted temperature management in children after cardiac arrest, initial oxygen concentration during resuscitation of newborns, and interventions for presyncope by first aid providers. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the certainty of the evidence on the basis of the Grading of Recommendations, Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence to Decision Framework Highlights sections. The task forces also listed priority knowledge gaps for further research
Structure and functional characterization of pyruvate decarboxylase from Gluconacetobacter diazotrophicus
BACKGROUND: Bacterial pyruvate decarboxylases (PDC) are rare. Their role in ethanol production and in bacterially
mediated ethanologenic processes has, however, ensured a continued and growing interest. PDCs from Zymomonas
mobilis (ZmPDC), Zymobacter palmae (ZpPDC) and Sarcina ventriculi (SvPDC) have been characterized and ZmPDC
has been produced successfully in a range of heterologous hosts. PDCs from the Acetobacteraceae and their role in
metabolism have not been characterized to the same extent. Examples include Gluconobacter oxydans (GoPDC),
G. diazotrophicus (GdPDC) and Acetobacter pasteutrianus (ApPDC). All of these organisms are of commercial importance.
RESULTS: This study reports the kinetic characterization and the crystal structure of a PDC from Gluconacetobacter
diazotrophicus (GdPDC). Enzyme kinetic analysis indicates a high affinity for pyruvate (KM 0.06 mM at pH 5), high
catalytic efficiencies, pHopt of 5.5 and Topt at 45 degrees C. The enzyme is not thermostable (T of
18 minutes at 60 degrees C) and the calculated number of bonds between monomers and dimers do not give clear indications
for the relatively lower thermostability compared to other PDCs. The structure is highly similar to those described for Z.
mobilis (ZmPDC) and A. pasteurianus PDC (ApPDC) with a rmsd value of 0.57 A for C? when comparing GdPDC to that
of ApPDC. Indole-3-pyruvate does not serve as a substrate for the enzyme. Structural differences occur in two loci,
involving the regions Thr341 to Thr352 and Asn499 to Asp503.
CONCLUSIONS: This is the first study of the PDC from G. diazotrophicus (PAL5) and lays the groundwork for future
research into its role in this endosymbiont. The crystal structure of GdPDC indicates the enzyme to be evolutionarily
closely related to homologues from Z. mobilis and A. pasteurianus and suggests strong selective pressure to keep the
enzyme characteristics in a narrow range. The pH optimum together with reduced thermostability likely reflect the
host organisms niche and conditions under which these properties have been naturally selected for. The lack of activity
on indole-3-pyruvate excludes this decarboxylase as the enzyme responsible for indole acetic acid production in
G. diazotrophicus.IS
Targeting the hedgehog transcription factors GLI1 and GLI2 restores sensitivity to vemurafenib-resistant human melanoma cells
BRAF inhibitor (BRAFi) therapy for melanoma patients harboring the V600E mutation is initially highly effective, but almost all patients relapse within a few months. Understanding the molecular mechanisms underpinning BRAFi-based therapy is therefore an important issue. Here we identified a previously unsuspected mechanism of BRAFi resistance driven by elevated Hedgehog (Hh) pathway activation that is observed in a cohort of melanoma patients after vemurafenib treatment. Specifically, we demonstrate that melanoma cell lines, with acquired in vitro-induced vemurafenib resistance, show increased levels of glioma-associated oncogene homolog 1 and 2 (GLI1/GLI2) compared with naive cells. We also observed these findings in clinical melanoma specimens. Moreover, the increased expression of the transcription factors GLI1/GLI2 was independent of canonical Hh signaling and was instead correlated with the noncanonical Hh pathway, involving TGF beta/SMAD (transforming growth factor-beta/Sma- and Mad-related family) signaling. Knockdown of GLI1 and GLI2 restored sensitivity to vemurafenib-resistant cells, an effect associated with both growth arrest and senescence. Treatment of vemurafenib-resistant cells with the GLI1/GLI2 inhibitor Gant61 led to decreased invasion of the melanoma cells in a three-dimensional skin reconstruct model and was associated with a decrease in metalloproteinase (MMP2/MMP9) expression and microphthalmia transcription factor upregulation. Gant61 monotherapy did not alter the drug sensitivity of naive cells, but could reverse the resistance of melanoma cells chronically treated with vemurafenib. We further noted that alternating dosing schedules of Gant61 and vemurafenib prevented the onset of BRAFi resistance, suggesting that this could be a potential therapeutic strategy for the prevention of therapeutic escape. Our results suggest that targeting the Hh pathway in BRAFi-resistant melanoma may represent a viable therapeutic strategy to restore vemurafenib sensitivity, reducing or even inhibiting the acquired chemoresistance in melanoma patients.Fapesp-grant number 2012/04194-1, 2013/05172-4, 2014/24400-0 and 2015/10821-7, CNPq-grant number 150447/2013-2 and 471512/2013-3 and PRODOC-grant no 3193-32/2010. Work in the lab of KS Smalley was supported by the National Institutes of Health grants R01 CA161107, R21 CA198550, and Skin SPORE grant P50 CA168536info:eu-repo/semantics/publishedVersio
Significance of glycolytic metabolism-related protein expression in colorectal cancer, lymph node and hepatic metastasis
Background: Colorectal cancer (CRC) is one of the most common malignancies and a leading cause of cancer death worldwide. Most cancer cells display high rates of glycolysis with production of lactic acid, which is then exported to the microenvironment by monocarboxylate transporters (MCTs). The main aim of this study was to evaluate the significance of MCT expression in a comprehensive series of primary CRC cases, lymph node and hepatic metastasis.
Methods: Expressions of MCT1, MCT4, CD147 and GLUT1 were studied in human samples of CRC, lymph node and hepatic metastasis, by immunohistochemistry.
Results: All proteins were overexpressed in primary CRC, lymph node and hepatic metastasis, when compared with non-neoplastic tissue, with exception of MCT1 in lymph node and hepatic metastasis. MCT1 and MCT4 expressions were associated with CD147 and GLUT1 in primary CRC. These markers were associated with clinical pathological features, reflecting the putative role of these metabolism-related proteins in the CRC setting.
Conclusion: These findings provide additional evidence for the pivotal role of MCTs in CRC maintenance and progression, and support the use of MCTs as biomarkers and potential therapeutic targets in primary and metastatic CRC.This work was supported by the Fundação para a Ciência e a Tecnologia
(FCT) grant ref. PTDC/SAU-FCF/104347/2008, under the scope of ‘Programa
Operacional Temático Factores de Competitividade’ (COMPETE) of ‘Quadro
Comunitário de Apoio III’ and co-financed by the Fundo Europeu De Desenvolvimento
Regional (FEDER). Ricardo Amorim was recipient of the fellowship
SFRH/BD/98002/2013, from Fundação para a Ciência e a Tecnologia (FCT
Portugal).info:eu-repo/semantics/publishedVersio
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
A study of the Z production cross-section in pp collisions at √s = 7 using tau final states
A measurement of the inclusive Z → ττ cross-section in pp collisions at
√s =7 is presented based on a dataset of 1.0 fb[superscript −1] collected by the LHCb detector. Candidates for Z → τ τ decays are identified through reconstructed final states with two muons, a muon and an electron, a muon and a hadron, or an electron and a hadron. The production cross-section for Z bosons, with invariant mass between 60 and 120 GeV/c[superscript 2], which decay to τ leptons with transverse momenta greater than 20 GeV/c and pseudorapidities between 2.0 and 4.5, is measured to be σ[subscript pp]→Z→ττ = 71.4 ± 3.5 ± 2.8 ± 2.5 pb; the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the integrated luminosity. The ratio of the cross-sections for Z → τ τ to Z → μμ is determined to be 0.93 ± 0.09, where the uncertainty is the combination of statistical, systematic, and luminosity uncertainties of the two measurements.National Science Foundation (U.S.
Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications
Superparamagnetic iron oxide nanoparticles
can providemultiple benefits for biomedical applications
in aqueous environments such asmagnetic separation or
magnetic resonance imaging. To increase the colloidal
stability and allow subsequent reactions, the introduction
of hydrophilic functional groups onto the particles’
surface is essential. During this process, the original
coating is exchanged by preferably covalently bonded
ligands such as trialkoxysilanes. The duration of the
silane exchange reaction, which commonly takes more
than 24 h, is an important drawback for this approach. In
this paper, we present a novel method, which introduces
ultrasonication as an energy source to dramatically
accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove
the generic character, different functional groups were
introduced on the surface including polyethylene glycol
chains, carboxylic acid, amine, and thiol groups. Their
colloidal stability in various aqueous buffer solutions as
well as human plasma and serum was investigated to
allow implementation in biomedical and sensing
applications.status: publishe
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