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Find video protocols related to scientific articles indexed in Pubmed.
Uniformization Method for Solving Cardiac Eletrophysiology Models Based on the Markov-Chain Formulation.
IEEE Trans Biomed Eng
PUBLISHED: 10-09-2014
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This paper compares different numerical methods for the solution of myocyte models of cardiac electrophysiology. In particular, it presents how the technique called Uniformization Method substantially increases the stability of simple first order methods such as Euler Explicit Method and Rush Larsen Method, for the solution of modern electrophysiology models that are based on Continuous Time Markov Chains for the description of sub-cellular structures, such as ion channels. Markov Chains are often associated with stiff ordinary differential equations that severely limit the time step used by these traditional methods. By using the Uniformization Method we could significantly increase the time steps for the solution of different cardiac electrophysiology models and improve the computational performance up to 150 times compared to the performance of Euler's and Rush- Larsen's methods.
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Morphological and molecular evidence for the occurrence of three Hippocampus species (Teleostei: Syngnathidae) in Brazil.
Zootaxa
PUBLISHED: 09-15-2014
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For many decades only two species of seahorses were recognized from Brazil: Hippocampus reidi Ginsburg, 1933, the long snout seahorse, and H. erectus Perry, 1810, the lined seahorse. The presence of a possible third species, recognized in 2002, brought about the need for a broad revision of the genus in Brazilian waters. A total of 335 specimens of seahorses, obtained from Brazilian and other collections, representing the three putative species from Brazil were analyzed: H. reidi, the species of greatest abundance and occurs in estuaries and the sea; H. erectus, which occurs only in the sea, and Hippocampus patagonicus was also determined to be present based on multiple specimens. Our morphometric / numerical and molecular analysis showed that the species currently identified as H. erectus in Brazil is actually H. patagonicus Piacentino & Luzatto, 2004. The existence of a possible third species, was instead based on the true H. erectus, as confirmed in the present study by the study of classical systematic and mitochondrial analysis. Thus, we recognize three species of seahorses in Brazil: H. erectus, H. reidi and H. patagonicus.
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Modeling IoT-based solutions using human-centric wireless sensor networks.
Sensors (Basel)
PUBLISHED: 08-25-2014
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The Internet of Things (IoT) has inspired solutions that are already available for addressing problems in various application scenarios, such as healthcare, security, emergency support and tourism. However, there is no clear approach to modeling these systems and envisioning their capabilities at the design time. Therefore, the process of designing these systems is ad hoc and its real impact is evaluated once the solution is already implemented, which is risky and expensive. This paper proposes a modeling approach that uses human-centric wireless sensor networks to specify and evaluate models of IoT-based systems at the time of design, avoiding the need to spend time and effort on early implementations of immature designs. It allows designers to focus on the system design, leaving the implementation decisions for a next phase. The article illustrates the usefulness of this proposal through a running example, showing the design of an IoT-based solution to support the first responses during medium-sized or large urban incidents. The case study used in the proposal evaluation is based on a real train crash. The proposed modeling approach can be used to design IoT-based systems for other application scenarios, e.g., to support security operatives or monitor chronic patients in their homes.
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Comparison of anti-anaerobic antimicrobial strategies in cancer patients with febrile neutropenia and gastrointestinal symptoms.
BMC Res Notes
PUBLISHED: 08-15-2014
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The current study sought to compare 28-day mortality rates in cancer patients with febrile neutropenia (FN) and gastrointestinal (GI) symptoms who underwent monotherapy using an antibiotic with antipseudomonal and anti-anaerobic activity (piperacillin-tazobactam or a carbapenem) and a group treated with a combination of cefepime-metronidazole.
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Spread of Oropouche virus into the central nervous system in mouse.
Viruses
PUBLISHED: 08-06-2014
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Oropouche virus (OROV) is an important cause of arboviral illness in Brazil and other Latin American countries, with most cases clinically manifested as acute febrile illness referred to as Oropouche fever, including myalgia, headache, arthralgia and malaise. However, OROV can also affect the central nervous system (CNS) with clinical neurological implications. Little is known regarding OROV pathogenesis, especially how OROV gains access to the CNS. In the present study, neonatal BALB/c mice were inoculated with OROV by the subcutaneous route and the progression of OROV spread into the CNS was evaluated. Immunohistochemistry revealed that OROV infection advances from posterior parts of the brain, including the periaqueductal gray, toward the forebrain. In the early phases of the infection OROV gains access to neural routes, reaching the spinal cord and ascending to the brain through brainstem regions, with little inflammation. Later, as infection progresses, OROV crosses the blood-brain barrier, resulting in more intense spread into the brain parenchyma, with more severe manifestations of encephalitis.
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On the coupling of two models of the human immune response to an antigen.
Biomed Res Int
PUBLISHED: 07-22-2014
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The development of mathematical models of the immune response allows a better understanding of the multifaceted mechanisms of the defense system. The main purpose of this work is to present a scheme for coupling distinct models of different scales and aspects of the immune system. As an example, we propose a new model where the local tissue inflammation processes are simulated with partial differential equations (PDEs) whereas a system of ordinary differential equations (ODEs) is used as a model for the systemic response. The simulation of distinct scenarios allows the analysis of the dynamics of various immune cells in the presence of an antigen. Preliminary results of this approach with a sensitivity analysis of the coupled model are shown but further validation is still required.
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Comparing Tactical Behaviour of Soccer Players in 3 vs. 3 and 6 vs. 6 Small-Sided Games.
J Hum Kinet
PUBLISHED: 07-08-2014
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The present study aimed to compare players' tactical behaviour in 3 vs. 3 and 6 vs. 6 soccer small-sided games (SSGs). The sample comprised 3,482 tactical actions performed by 18 U-11 youth soccer players from a Portuguese club, in 3 vs. 3 and 6 vs. 6 SSGs. All participants played eight minutes in both situations and field size was adapted according to the number of players involved (30 m × 19.5 m for 3 vs. 3 and 60 m × 39 m for 6 vs. 6). The System of Tactical Assessment in Soccer (FUT-SAT) was used for data collection and analyses. Descriptive analysis was conducted to verify frequencies and percentages of the variables assessed. The chi-squared (?(2)) test was performed to compare the frequencies of the variables between 3 vs. 3 and 6 vs. 6 SSGs and Standardized Residuals (e) were used to examine the influence of the frequency of one or more variables within 3 vs. 3 and 6 vs. 6 SSGs. Data treatment was performed through SPSS for Windows®, version 18.0. Results indicated that players displayed safer behaviours in 6 vs. 6 SSG and more aggressive behaviours in 3 vs. 3 SSG. Findings can aid coaches and teachers to develop different players' tactical skills according to the chosen SSG (3 vs. 3 or 6 vs. 6) form.
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Comparative analysis electroencephalographic of alpha, Beta and gamma bands of a healthy individual and one with hemiparesis.
J Phys Ther Sci
PUBLISHED: 06-30-2014
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[Purpose] The study analyzed the electroencephalographic (EEG) data of the central cortical areas, during execution of the motor gestures of feeding, activation of the system of mirror neurons, and imagery between a right hemiparetic volunteer (RHV) and a healthy volunteer (HV). [Subjects and Methods] The volunteers' EEG data were recorded with their eyes open for 4 minutes while they performed five experimental tasks. [Results] The alpha band, absolute power value of HV was lower than that of RHV. In the beta band, during the practice condition, there was an increase in the magnitude of the absolute power value of HV at T3, possibly because T3 is representative of secondary motor areas that work with cortical neurons related to planning and organizing sequence of movements performed by the hands. The gamma band is related to the state of preparation for movement and memory. The results of this study indicate that there was increased activation of the gamma frequency band of HV. [Conclusion] The findings of this study have revealed the changes in pattern characteristics of each band which may be associated with the brain injury of the hemiparetic patient.
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Empathy in Brazilian nursing professionals: A descriptive study.
Nurs Ethics
PUBLISHED: 06-18-2014
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Essential for the help relation, empathy is the ability to understand, share, and perceive the subjective experience of other human beings.
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Viral epidemiology of respiratory infections among children at a tertiary hospital in Southern Brazil.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 05-28-2014
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This study reports the pediatric epidemiology of respiratory syncytial virus (RSV), influenza (IF), parainfluenza (PIV), and adenovirus (ADV) at Hospital de Clínicas de Porto Alegre.
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Association between adherence to an antimicrobial stewardship program and mortality among hospitalised cancer patients with febrile neutropaenia: a prospective cohort study.
BMC Infect. Dis.
PUBLISHED: 05-15-2014
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Initial management of chemotherapy-induced febrile neutropaenia (FN) comprises empirical therapy with a broad-spectrum antimicrobial. Currently, there is sufficient evidence to indicate which antibiotic regimen should be administered initially. However, no randomized trial has evaluated whether adherence to an antimicrobial stewardship program (ASP) results in lower rates of mortality in this setting. The present study sought to assess the association between adherence to an ASP and mortality among hospitalised cancer patients with FN.
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Translation into Portuguese and validation of the Blood Donation Reactions Inventory.
Rev Bras Hematol Hemoter
PUBLISHED: 05-03-2014
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the Blood Donation Reactions Inventory (BDRI) scale was proposed as part of a study about the predictors of psychological reactions in volunteer blood donors, as uncomfortable reactions are associated with a lower probability to return for further donations.
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Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women.
Arq Bras Endocrinol Metabol
PUBLISHED: 03-24-2014
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Physical exercise is an important stimulus for osteoporosis prevention and treatment. However, it is not clear yet which modality would be better to stimulate bone metabolism and enhance physical function of postmenopausal women. This review paper aims to summarize and update present knowledge on the effects of different kinds of aquatic and ground physical exercises on bone metabolism and physical function of postmenopausal women. Moderate to intense exercises, performed in a high speed during short intervals of time, in water or on the ground, can be part of a program to prevent and treat postmenopausal osteoporosis. Mechanical vibration has proven to be beneficial for bone microarchitecture, improving bone density and bone strength, as well as increasing physical function. Although impact exercises are recognized as beneficial for the stimulation of bone tissue, other variables such as muscle strength, type of muscle contraction, duration and intensity of exercises are also determinants to induce changes in bone metabolism of postmenopausal women. Not only osteoanabolic exercises should be recommended; activities aimed to develop muscle strength and body balance and improve the proprioception should be encouraged to prevent falls and fractures.
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Mortality related to coagulase-negative staphylococcal bacteremia in febrile neutropenia: A cohort study.
Can J Infect Dis Med Microbiol
PUBLISHED: 03-18-2014
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Coagulase-negative staphylococci (CoNS) are currently the most common isolates recovered from the blood of patients with cancer and febrile neutropenia (FN).
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Localization of ectopic and supernumerary parathyroid glands in patients with secondary and tertiary hyperparathyroidism: surgical description and correlation with preoperative ultrasonography and Tc99m-Sestamibi scintigraphy.
Braz J Otorhinolaryngol
PUBLISHED: 03-15-2014
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Hyperparathyroidism is an expected metabolic consequence of chronic kidney disease (CKD). Ectopic and/or supernumerary parathyroid glands (PT) may be the cause of surgical failure in patients undergoing total parathyroidectomy (PTX).
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An efficient finite element approach for modeling fibrotic clefts in the heart.
IEEE Trans Biomed Eng
PUBLISHED: 02-22-2014
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Advanced medical imaging technologies provide a wealth of information on cardiac anatomy and structure at a paracellular resolution, allowing to identify microstructural discontinuities which disrupt the intracellular matrix. Current state-of-the-art computer models built upon such datasets account for increasingly finer anatomical details, however, structural discontinuities at the paracellular level are typically discarded in the model generation process, owing to the significant costs which incur when using high resolutions for explicit representation. In this study, a novel discontinuous finite element (dFE) approach for discretizing the bidomain equations is presented, which accounts for fine-scale structures in a computer model without the need to increase spatial resolution. In the dFE method, this is achieved by imposing infinitely thin lines of electrical insulation along edges of finite elements which approximate the geometry of discontinuities in the intracellular matrix. Simulation results demonstrate that the dFE approach accounts for effects induced by microscopic size scale discontinuities, such as the formation of microscopic virtual electrodes, with vast computational savings as compared to high resolution continuous finite element models. Moreover, the method can be implemented in any standard continuous finite element code with minor effort.
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Bioabsorption of cadmium, copper and lead by the red macroalga Gelidium floridanum: physiological responses and ultrastructure features.
Ecotoxicol. Environ. Saf.
PUBLISHED: 02-20-2014
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Heavy metals, such as lead, copper, cadmium, zinc, and nickel, are among the most common pollutants found in both industrial and urban effluents. High concentrations of these metals cause severe toxic effects, especially to organisms living in the aquatic ecosystem. Cadmium (Cd), lead (Pb) and copper (Cu) are the heavy metals most frequently implicated as environmental contaminants, and they have been shown to affect development, growth, photosynthesis and respiration, and morphological cell organization in seaweeds. This paper aimed to evaluate the effects of 50?M and 100?M of Cd, Pb and Cu on growth rates, photosynthetic pigments, biochemical parameters and ultrastructure in Gelidium floridanum. To accomplish this, apical segments of G. floridanum were individually exposed to the respective heavy metals over a period of 7 days. Plants exposed to Cd, Cu and Pb showed discoloration of thallus pigmentation, chloroplast alteration, especially degeneration of thylakoids, and decrease in photosynthetic pigments, such as chlorophyll a and phycobiliproteins, in samples treated with Cd and Cu. Moreover, cell wall thickness and the volume of plastoglobuli increased. X-ray microanalysis detected Cd, Cu and Pb absorption in the cell wall. The results indicate that Cd, Pb and Cu negatively affect metabolic performance and cell ultrastructure in G. floridanum and that Cu was more toxic than either Pb or Cd.
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Evaluation of respiratory syncytial virus group A and B genotypes among nosocomial and community-acquired pediatric infections in Southern Brazil.
Virol. J.
PUBLISHED: 02-11-2014
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Respiratory syncytial virus (RSV) is the main cause of lower respiratory tract illness in children worldwide. Molecular analyses show two distinct RSV groups (A and B) that comprise different genotypes. This variability contributes to the capacity of RSV to cause yearly outbreaks. These RSV genotypes circulate within the community and within hospital wards. RSV is currently the leading cause of nosocomial respiratory tract infections in pediatric populations. The aim of this study was to evaluate the G protein gene diversity of RSV amplicons.
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Toxicological effects of copper oxide nanoparticles on the growth rate, photosynthetic pigment content, and cell morphology of the duckweed Landoltia punctata.
Protoplasma
PUBLISHED: 02-04-2014
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Recently, the application of copper oxide nanoparticles (CuO-NPs) has increased considerably, primarily in scientific and industrial fields. However, studies to assess their health risks and environmental impacts are scarce. Therefore, the present study aims to evaluate the toxicological effects of CuO-NPs on the duckweed species Landoltia punctata, which was used as a test organism. To accomplish this, duckweed was grown under standard procedures according to ISO DIS 20079 and exposed to three different concentrations of CuO-NPs (0.1, 1.0, and 10.0?g L(-1)), with one control group (without CuO-NPs). The toxicological effects were measured based on growth rate inhibition, changes in the plant's morphology, effects on ultrastructure, and alterations in photosynthetic pigments. The morphological and ultrastructural effects were evaluated by electronic, scanning and light microscopic analysis, and CuO-NPs were characterized using transmission electron microscopy (TEM), zeta potential, and superficial area methods of analysis. This analysis was performed to evaluate nanoparticle size and form in solution and sample stability. The results showed that CuO-NPs affected morphology more significantly than growth rate. L. punctata also showed the ability to remove copper ions. However, for this plant to be representative within the trophic chain, the biomagnification of effects must be assessed.
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Vancomycin-resistant Enterococcus faecium Bacteremia in a tertiary care hospital: epidemiology, antimicrobial susceptibility, and outcome.
Biomed Res Int
PUBLISHED: 01-25-2014
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Vancomycin-resistant Enterococcus faecium (VREF) has emerged as a relevant multidrug-resistant pathogen and potentially lethal etiology of health care associated infections worldwide. The objective of this retrospective cohort study was to assess factors associated with mortality in patients with VREF bacteremia in a major tertiary referral hospital in Southern Brazil. All documented cases of bacteremia identified between May 2010 and July 2012 were evaluated. Cox regression was performed to determine whether the characteristics related to the host or antimicrobial treatment were associated with the all-cause 30-day mortality. In total, 35 patients with documented VREF bacteremia were identified during the study period. The median APACHE-II score of the study population was 26 (interquartile range: 10). The overall 30-day mortality was 65.7%. All VREF isolates were sensitive to linezolid, daptomycin, and quinupristin-dalfopristin. Linezolid was the only antimicrobial agent with in vitro activity against VREF that was administered to the cohort. After multivariate analysis, linezolid treatment (HR, 0.08; 95% CI, 0.02-0.27) and presence of acute kidney injury at the onset of bacteremia (HR, 4.01; 95% CI, 1.62-9.94) were independently associated with mortality. Presentation with acute kidney injury and lack of treatment with an effective antibiotic poses risk for mortality in patients with VREF bacteremia.
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Association between religiousness and blood donation among Brazilian postgraduate students from health-related areas.
Rev Bras Hematol Hemoter
PUBLISHED: 01-22-2014
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The aim of this study was to examine the association between religiousness and blood donation among postgraduate students.
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Energy-aware topology control strategy for human-centric wireless sensor networks.
Sensors (Basel)
PUBLISHED: 01-20-2014
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The adoption of mobile and ubiquitous solutions that involve participatory or opportunistic sensing increases every day. This situation has highlighted the relevance of optimizing the energy consumption of these solutions, because their operation depends on the devices' battery lifetimes. This article presents a study that intends to understand how the prediction of topology control messages in human-centric wireless sensor networks can be used to help reduce the energy consumption of the participating devices. In order to do that, five research questions have been defined and a study based on simulations was conducted to answer these questions. The obtained results help identify suitable mobile computing scenarios where the prediction of topology control messages can be used to save energy of the network nodes. These results also allow estimating the percentage of energy saving that can be expected, according to the features of the work scenario and the participants behavior. Designers of mobile collaborative applications that involve participatory or opportunistic sensing, can take advantage of these findings to increase the autonomy of their solutions.
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Growth inhibitory effects of the Diruthenium-Ibuprofen compound, [Ru2Cl(Ibp) 4], in human glioma cells in vitro and in the rat C6 orthotopic glioma in vivo.
J. Biol. Inorg. Chem.
PUBLISHED: 01-10-2014
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The Diruthenium-Ibuprofen compound [Ru2Cl(Ibp)4] (or RuIbp) is known to cause significant inhibition of C6 rat glioma cell proliferation in vitro. RuIbp increased the expression of cell cycle-related proteins such as p21 and p27 and the pro-apoptotic protein Bax, as well as causing a reduction in mitochondrial membrane potential and a modest increase in apoptosis in vitro. The present study extended these findings by (i) investigating the effects of RuIbp on human glioma cell line proliferation in vitro and (ii) investigating the acute and chronic toxicology of the compound in normal Wistar rats. The compound was then tested for its anti-tumour properties by either chronic 14 days intra-peritoneal (IP) administration or chronic Alzet osmotic pump infusion, in the rat C6 orthotopic glioma model in vivo. The IP injection of RuIbp caused a 41 % inhibition of tumour area without significant toxic effects but with an increase in blood neutrophils and monocytes and a decrease in blood lymphocytes. In an attempt to reduce this effect RuIbp was administered by Alzet osmotic pump infusion directly into the tumour at a dose of 15 mg/kg with an infusion rate of 0.5 µL/h for 14 days. The direct infusion of RuIbp caused a 45 % inhibition of tumour area without alterations in differential blood leukocyte counts. These results prove the efficacy of RuIbp in human glioma cell lines in vitro and in an in vivo glioma model and point to its potential as an inhibitor of tumour growth in vivo.
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MBD3/NuRD facilitates induction of pluripotency in a context-dependent manner.
Cell Stem Cell
PUBLISHED: 01-08-2014
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The Nucleosome Remodeling and Deacetylase (NuRD) complex is essential for embryonic development and pluripotent stem cell differentiation. In this study, we investigated whether NuRD is also involved in the reverse biological process of induction of pluripotency in neural stem cells. By knocking out MBD3, an essential scaffold subunit of the NuRD complex, at different time points in reprogramming, we found that efficient formation of reprogramming intermediates and induced pluripotent stem cells from neural stem cells requires NuRD activity. We also show that reprogramming of epiblast-derived stem cells to naive pluripotency requires NuRD complex function and that increased MBD3/NuRD levels can enhance reprogramming efficiency when coexpressed with the reprogramming factor NANOG. Our results therefore show that the MBD3/NuRD complex plays a key role in reprogramming in certain contexts and that a chromatin complex required for cell differentiation can also promote reversion back to a naive pluripotent cell state.
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Characteristics of undiagnosed COPD in a senior community center.
Int J Chron Obstruct Pulmon Dis
PUBLISHED: 01-01-2014
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To determine the characteristics of undiagnosed chronic obstructive pulmonary disease (COPD) in a senior community center.
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Kinetic and mechanistic studies on reactions of diruthenium(ii,iii) with biologically relevant reducing agents.
Dalton Trans
PUBLISHED: 10-01-2013
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Diruthenium(ii,iii)-tetracarboxylates have shown promising anticancer properties as metallotherapeutics. On the basis of the role that bio-reducing agents may play on the mode of action of ruthenium-based anticancer drugs, we performed detailed kinetic studies on the reaction of ascorbic acid and glutathione with the [Ru2(RCOO)4](+) paddlewheel framework by using the non-drug, diaqua complex ion [Ru2(CH3COO)4(H2O)2](+). In the presence of the reducing agents, the diaqua-Ru2 species first undergo a ligand substitution reaction by which the axially-coordinated water is displaced by the reducing agent. In both cases, this reaction is followed by an intra-molecular electron transfer process during which the metal-metal center is reduced from Ru2(5+) to Ru2(4+) and the reducing agent is oxidized. Product analyses were performed with the application of ESI-MS and (1)H-NMR techniques. Rate and activation parameters are reported for the different reaction steps.
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Tadalafil-induced improvement in left ventricular diastolic function in resistant hypertension.
Eur. J. Clin. Pharmacol.
PUBLISHED: 09-23-2013
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Left ventricular hypertrophy and diastolic dysfunction (LVDD) remain highly frequent markers of cardiac damage and risk of progression to symptomatic heart failure, especially in resistant hypertension (RHTN). We have previously demonstrated that administration of sildenafil in hypertensive rats improves LVDD, restoring phosphodiesterase type 5 (PDE-5) inhibition in cardiac myocytes.
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Five-year follow-up of modified implant-supported overdenture in an iliac crest autograft failure: clinical report.
J Craniofac Surg
PUBLISHED: 09-17-2013
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The treatment of extensive pathologic lesions in the jaw, most of the time, can generate rehabilitation problems to the patient. The solid ameloblastoma is a locally invasive odontogenic tumor with a high recurrence rate. Its treatment is aggressive and accomplished through resection with safety margin. The criterion standard for reconstruction is autogenous bone, but it can provide a high degree of resorption, causing inconvenience to the patient because of lack of rehabilitative option. This study aimed to describe a patient with ameloblastoma treated through resection and reconstruction with autogenous bone graft, in which, after an extensive resorption of the graft was made, a modified bar was applied to support a prosthetic implant overdenture.
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Management of pure medial orbital wall fracture with autogenous bone graft.
J Craniofac Surg
PUBLISHED: 09-17-2013
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The orbit is an irregular conical cavity formed from 7 bones including the frontal, sphenoid, zygomatic, maxillary, ethmoid, lacrimal, and palatine bones. Fractures of the internal orbit can cause a number of problems, including diplopia, ocular muscle entrapment, and enophthalmos. Although muscle entrapment is relatively rare, diplopia and enophthalmos are relatively common sequelae of internal orbital fractures. Medial orbital wall fracture is relatively uncommon and represents a challenge for its anatomical reconstruction. In this context, autogenous bone graft has been the criterion standard to provide framework for facial skeleton and orbital walls. Therefore, it is possible to harvest grafts of varying size and contour, and the operation is performed through the bicoronal incision, which is the usual approach to major orbital reconstruction. Thus, this article aimed to describe a patient with a pure medial orbital wall fracture, and it was causing diplopia and enophthalmos. The orbital fracture was treated using autogenous bone graft from calvarial bone. The authors show a follow-up of 12 months, with facial symmetry and without diplopia and enophthalmos. In addition, a computed tomography scan shows excellent bone healing at the anterior and posterior parts of the medial orbital wall reconstruction.
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Community-acquired pneumonia at the Hospital de Clínicas de Porto Alegre: evaluation of a care protocol.
Braz J Infect Dis
PUBLISHED: 07-02-2013
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To assess the adequacy of medical prescriptions for community-acquired pneumonia at the emergency department of the Hospital de Clínicas de Porto Alegre, we conducted a prospective cohort study, from January through April 2011. All patients with suspected pneumonia were selected from the first prescription of antimicrobials held in the emergency room. Patients with a description of pneumonia, community-acquired pneumonia, respiratory infection, or other issues related to community-acquired pneumonia were selected for review. Two-hundred and fifteen patients were studied. Adherence to the hospital care protocol was: 11.2% for the initial recommended tests (chest X-ray and collection of sputum sample), 34.4% for blood cultures, and 92.1% for the antimicrobial choice. Sixty percent of the prescriptions consisted of a combination of drugs, and the association of beta-lactam and macrolide was the most common. The Hospital Infection Control Committee evaluated patients prescriptions within a median time of 23.5h (IQR 25-75%, 8-24). Negative evaluations accounted for 10% of prescriptions (n=59). Fourteen percent of the patients died during hospitalization. In the multivariate analysis, Pneumonia Severity Index Score and use of ampicillin+sulbactam alone were independently related to in-hospital mortality. There was a high adherence to the hospitals CAP protocol, in relation to antimicrobial choice. Severity score and use of ampicillin+sulbactam alone were independently associated to in-hospital death.
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Reduced frequency of T lymphocytes expressing CTLA-4 in frontotemporal dementia compared to Alzheimers disease.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 06-26-2013
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Studies suggest that inflammation is involved in the neurodegenerative cascade of dementias. Immunological mechanisms may be part of the pathophysiological process in frontotemporal dementia (FTD), but up till now only vague evidence of such mechanisms has been presented. The B7- CD28/CTLA-4 pathway is an important immunological signaling pathway involved in modulation of T cell activation. The aim of this study was to compare the expression of molecules associated with co-stimulatory signaling in peripheral blood mononuclear cells (PBMC) of FTD to Alzheimer disease (AD) and control groups. Our results confirm the previous demonstrated increased expression of CD80 in CD14+ Alzheimer patients T cells but show, for the first time, a reduction in the expression of CTLA-4 in CD4+ FTD cells. As CTLA-4 is the most potent negative regulators of T-cell activation we speculated that peripheral T lymphocytes in FTD are more activated and this could be involved in the neurodegeneration observed in this dementia.
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Ambient pH sensing in filamentous fungi: Pitfalls in elucidating regulatory hierarchical signaling networks.
IUBMB Life
PUBLISHED: 06-09-2013
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In this article, the experiments used to construct the ambient pH-signaling network involved in the secretion of enzymes by filamentous fungi have been reviewed, focusing on the phosphate-repressible phosphatases in Aspergillus nidulans. Classic and molecular genetics have been used to demonstrate that proteolysis of the transcription factor PacC at alkaline ambient pH is imperative for its action, implying that the full-length version is not an active molecular form of PacC. It has been hypothesized that the transcriptional regulator PacC may be functional at both acidic and alkaline ambient pH, in either the full-length or the proteolyzed form, if it carries a pal-dependent molecular tag. The products of the pal genes are involved in a metabolic pathway that led to the synthesis of effector molecules that tag the pacC product, perhaps facilitating its proteolysis. © 2013 IUBMB Life, 65(11):930-935, 2013.
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Brazilian Academy of Rhinology position paper on topical intranasal therapy.
Braz J Otorhinolaryngol
PUBLISHED: 06-08-2013
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This documents aims at educating those who treat sinonasal diseases - both general practitioners and specialists - about topical nasal treatments. By means of scientific evidence reviews, the Brazilian Academy of Rhinology provides its practical and updated guidelines on the most utilized topical nasal medication, except for the drugs that have topical antibiotics in their formulas.
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Risk factors for multidrug-resistant bacteremia in hospitalized cancer patients with febrile neutropenia: A cohort study.
Am J Infect Control
PUBLISHED: 05-13-2013
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We conducted a prospective cohort study in a single tertiary hospital with the aim of assessing predictors of multidrug-resistant bacteremia in 307 cases of febrile neutropenia in adult patients with cancer. On multivariate analysis using stepwise logistic regression, age (P = .009), duration of neutropenia (P = .022), and presence of an indwelling central venous catheter (P = .022) were associated with bloodstream infection by multidrug-resistant bacteria.
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DFPE, partially fluorinated ether: a novel approach for experimental intravitreal tamponade.
Retina (Philadelphia, Pa.)
PUBLISHED: 04-26-2013
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To evaluate decafluoro-di-n-pentyl ether (DFPE) as a vitreous tamponade by examining ocular tolerance in rabbits eyes.
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Hypoadiponectinemia and aldosterone excess are associated with lack of blood pressure control in subjects with resistant hypertension.
Hypertens. Res.
PUBLISHED: 04-18-2013
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Obesity, arterial stiffness and high aldosterone levels can interact to cause resistant hypertension (RHTN). Lower adiponectin (APN) levels may be significantly associated with hypertension. However, the importance of hypoadiponectinemia as a complicating factor in the lack of blood pressure (BP) control in individuals with RHTN has not been demonstrated. Ninety-six RHTN patients were classified into uncontrolled (UCRHTN, n=44) and controlled (CRHTN, n=52) subgroups. Their APN and aldosterone levels, office and ambulatory BP (ABPM) measurements, endothelium-dependent brachial artery responses (flow-mediated dilation (FMD)), left ventricular mass index (LVMI) and pulse wave velocity (PWV) were evaluated. The UCRHTN subgroup had increased aldosterone levels, as well as higher LVMI and PWV. In addition, lower APN levels and impaired FMD response were found in this subgroup. The brachial and ABPM pulse pressures were inversely associated with the APN levels (r=-0.45, P=0.002; r=-0.33, P=0.03, respectively), as were the aldosterone levels and the PWV (r=-0.38, P=0.01; r=-0.36, P=0.02, respectively) in UCRHTN patients. The PWV was only significantly influenced by the APN level in the UCRHTN subgroup in the multivariate regression analysis. None of the correlations mentioned above were observed in the CRHTN subgroup. Hypoadiponectinemia and high aldosterone levels may therefore be implicated in resistance to antihypertensive therapy related to arterial stiffness.
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On the computational modeling of the innate immune system.
BMC Bioinformatics
PUBLISHED: 04-17-2013
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In recent years, there has been an increasing interest in the mathematical and computational modeling of the human immune system (HIS). Computational models of HIS dynamics may contribute to a better understanding of the relationship between complex phenomena and immune response; in addition, computational models will support the development of new drugs and therapies for different diseases. However, modeling the HIS is an extremely difficult task that demands a huge amount of work to be performed by multidisciplinary teams. In this study, our objective is to model the spatio-temporal dynamics of representative cells and molecules of the HIS during an immune response after the injection of lipopolysaccharide (LPS) into a section of tissue. LPS constitutes the cellular wall of Gram-negative bacteria, and it is a highly immunogenic molecule, which means that it has a remarkable capacity to elicit strong immune responses. We present a descriptive, mechanistic and deterministic model that is based on partial differential equations (PDE). Therefore, this model enables the understanding of how the different complex phenomena interact with structures and elements during an immune response. In addition, the models parameters reflect physiological features of the system, which makes the model appropriate for general use.
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Electroanatomical characterization of atrial microfibrosis in a histologically detailed computer model.
IEEE Trans Biomed Eng
PUBLISHED: 04-03-2013
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Fibrosis is thought to play an important role in the formation and maintenance of atrial fibrillation (AF). The propensity of fibrosis to increase AF vulnerability depends not only on its amount, its texture plays a crucial role as well. While the detection of fibrotic tissue patches in the atria with extracellular recordings is feasible based on the analysis of electrogram fractionation, as used in clinical practice to identify ablation targets, the classification of fibrotic texture is a more challenging problem. This study seeks to establish a method for the electroanatomical characterization of the fibrotic textures based on the analysis of electrogram fractionation. The proposed method exploits the dependence of fractionation patterns on the incidence direction of wavefronts which differs significantly as a function of texture. A histologically detailed computer model of the right atrial isthmus was developed for testing the method. A stimulation protocol was conceived which generated various incidence directions for any given recording site where electrograms were computed. A classification method is derived then for discriminating three types of fibrosis, no fibrosis (control), diffuse, and patchy fibrosis. Simulation results showed that electrogram fractionation and amplitudes and their dependence upon incidence direction allow a robust discrimination between different classes of fibrosis. Finally, to minimize the technical effort, sensitivity analysis was performed to identify a minimum number of incidence directions required for robust classification.
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The effects of lead and copper on the cellular architecture and metabolism of the red alga Gracilaria domingensis.
Microsc. Microanal.
PUBLISHED: 04-03-2013
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The effect of lead and copper on apical segments of Gracilaria domingensis was examined. Over a period of 7 days, the segments were cultivated with concentrations of 5 and 10 ppm under laboratory conditions. The samples were processed for light, confocal, and electron microscopy, as well as histochemistry, to evaluate growth rates, mitochondrial activity, protein levels, chlorophyll a, phycobiliproteins, and carotenoids. After 7 days of exposure to lead and copper, growth rates were slower than control, and biomass loss was observed on copper-treated plants. Ultrastructural damage was primarily observed in the internal organization of chloroplasts and cell wall thickness. X-ray microanalysis detected lead in the cell wall, while copper was detected in both the cytoplasm and cell wall. Moreover, lead and copper exposure led to photodamage of photosynthetic pigments and, consequently, changes in photosynthesis. However, protein content and glutathione reductase activity decreased only in the copper treatments. In both treatments, decreased mitochondrial NADH dehydrogenase activity was observed. Taken together, the present study demonstrates that (1) heavy metals such as lead and copper negatively affect various morphological, physiological, and biochemical processes in G. domingensis and (2) copper is more toxic than lead in G. domingensis.
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High-intensity aquatic exercises (HydrOS) improve physical function and reduce falls among postmenopausal women.
Menopause
PUBLISHED: 03-28-2013
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This study aims to investigate the effects of an aquatic exercise program (HydrOS) on neuromuscular function and falls among postmenopausal women.
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A defined Oct4 level governs cell state transitions of pluripotency entry and differentiation into all embryonic lineages.
Nat. Cell Biol.
PUBLISHED: 03-26-2013
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Oct4 is considered a master transcription factor for pluripotent cell self-renewal, but its biology remains poorly understood. Here, we investigated the role of Oct4 using the process of induced pluripotency. We found that a defined embryonic stem cell (ESC) level of Oct4 is required for pluripotency entry. However, once pluripotency is established, the Oct4 level can be decreased up to sevenfold without loss of self-renewal. Unexpectedly, cells constitutively expressing Oct4 at an ESC level robustly differentiated into all embryonic lineages and germline. In contrast, cells with low Oct4 levels were deficient in differentiation, exhibiting expression of naive pluripotency genes in the absence of pluripotency culture requisites. The restoration of Oct4 expression to an ESC level rescued the ability of these to restrict naive pluripotent gene expression and to differentiate. In conclusion, a defined Oct4 level controls the establishment of naive pluripotency as well as commitment to all embryonic lineages.
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Surgical treatment of severe epistaxis: an eleven-year experience.
Braz J Otorhinolaryngol
PUBLISHED: 03-19-2013
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Epistaxis is one of the most prevalent emergencies in ENT practice, and its surgical treatment is part of the routine at services for emergency care, especially in cases refractory to clinical procedures.
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Changes in hand hygiene compliance after a multimodal intervention and seasonality variation.
Am J Infect Control
PUBLISHED: 03-08-2013
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Hand hygiene is the most important measure to reduce health care-related infections and colonization with multiresistant micro-organisms. We sought to determine the rate and seasonality of handwashing compliance in a university-affiliated hospital.
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Parathyroid carcinoma and hungry bone syndrome.
Arq Bras Endocrinol Metabol
PUBLISHED: 02-27-2013
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We hereby report two patients with parathyroid carcinoma presenting extremely high calcium and PTH levels, severe bone disease, and palpable neck mass at diagnosis. They both underwent parathyroidectomy, and one of them evolved to lung metastasis. Important hypocalcemia was observed after surgery in both: after parathyroidectomy in one patient, and only after surgical removal of the metastasis in the other. Both required intravenous calcium replacement, thus revealing hungry bone syndrome (HBS). HBS usually reflects rapid mineralization after correction of hyperparathyroidism. The more severe the bone disease before surgery, the more prone the patient is to HBS after surgery. Despite being an unfavorable outcome, HBS state suggests that surgical removal of hypersecretory parathyroid tissue was accomplished. In this study, HBS was observed in both patients, who presented severe bone disease prior to surgery. HBS would be expected post-operatively in successful parathyroid carcinoma removal.
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The benefits of a high-intensity aquatic exercise program (HydrOS) for bone metabolism and bone mass of postmenopausal women.
J. Bone Miner. Metab.
PUBLISHED: 02-21-2013
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This study aimed to evaluate the 24-week effects of a high-intensity aquatic exercise program on bone remodeling markers and bone mass of postmenopausal women. In this randomized, controlled trial we studied 108 women (58.8 ± 6.4 years), randomized into Aquatic Exercise Group (AEG), n = 64, performing 24 weeks of aquatic exercises, and Control Group (CG), n = 44, sedentary. They had their fasting morning blood sample collected for the measures of intact parathyroid hormone (iPTH), procollagen type 1 amino-terminal propeptide (P1NP) and carboxy-terminal cross-linking telopeptide of type I collagen (CTx). Bone mass was measured by dual-energy X-ray absorptiometry before and after the intervention. Participants of both groups received a daily supplementation of 500 mg of elementary calcium and 1,000 IU of vitamin D (cholecalciferol). Results showed an augment in bone formation marker (P1NP) only in the AEG (15.8 %; p = 0.001), and although both groups experienced significant enhancements in bone resorption marker (CTx), this increase was less considerable in the AEG (15 % in the AEG and 29 % in the CG). IPTH was increased by 19 % in the CG (p = 0.003) at the end. The femoral trochanter BMD presented a 1.2 % reduction in the CG (p = 0.009), whereas in the AEG no change was observed (p = 0.069). The proposed aquatic exercise program was efficient in attenuating bone resorption raise and enhancing bone formation, which prevented the participants in the AEG from reducing the femoral trochanter BMD, as happened in the CG.
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Microbiologic isolates and risk factors associated with antimicrobial resistance in patients admitted to the intensive care unit in a tertiary care hospital.
Am J Infect Control
PUBLISHED: 02-16-2013
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This study reviewed the clinical and microbiologic data for patients admitted to the intensive care unit with hospital-acquired infections. In the multivariate analysis, AIDS and previous antibiotic use were associated with the emergence of multiresistant bacteria. Hematologic diseases, length of stay, number of days on central venous catheter, antimicrobial use, and presence of multiresistant bacteria were associated with death. The previous use of antibiotics and the length of the hospital stay contribute to the development of infections caused by multiresistant gram-negative bacteria.
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Antimicrobial stewardship through telemedicine in a community hospital in Southern Brazil.
J Telemed Telecare
PUBLISHED: 02-06-2013
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We developed an antimicrobial stewardship programme, based on telemedicine, for a remote community hospital in southern Brazil. Expertise in infectious diseases was provided from a 250-bed tertiary hospital for cardiology patients located 575 km away. At the community hospital, antimicrobial prescriptions were completed via a secure web site. A written reply was sent back to the prescriber by email and SMS text message. During a 4-month study period there were 81 prescriptions for 76 patients. Most antimicrobial prescriptions (67%) were for respiratory infections. Ampicillin was prescribed in 44% of cases (n = 56), gentamicin in 18% of cases (n = 23) and azithromycin in 18% of cases (n = 23). Two infectious diseases specialists independently reviewed each antimicrobial prescription. A total of 41 prescriptions (55%) were considered inappropriate. The median time to obtain a second opinion via the web site was 22 min (interquartile range 12-55). Overall compliance with the recommendations of the infectious diseases specialist was 100% (81 out of 81 requests). Telemedicine appears to have a useful potential role in antimicrobial stewardship programmes.
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Intraoperative PTH cutoff definition to predict successful parathyroidectomy in secondary and tertiary hyperparathyroidism.
Braz J Otorhinolaryngol
PUBLISHED: 01-23-2013
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In order to improve success rates in surgery of renal hyperparathyroidism, we evaluated intraoperative PTH (IOPTH) measurement utility.
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Does haemosporidian infection affect hematological and biochemical profiles of the endangered Black-fronted piping-guan (Aburria jacutinga)?
PeerJ
PUBLISHED: 01-01-2013
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Infectious diseases can cause deleterious effects on bird species, leading to population decline and extinction. Haemosporidia can be recognized by their negative effects on host fitness, including reproductive success and immune responses. In captivity, outbreaks of haemosporidian infection have been observed in birds in zoos and aviaries. The endemic Brazilian Atlantic rainforest species Aburria jacutinga is one of the most endangered species in the Cracidae family, and wild populations of this species are currently found mainly in conservation areas in only two Brazilian states. In this study, we aimed to evaluate the effects of avian haemosporidia on hematological and biochemical parameters in two captive populations of A. jacutinga. Forty-two animals were assessed, and the haemosporidian prevalence was similar for males and females. The occurrence of haemosporidian infection in captive A. jacutinga observed in this study was similar to results found in other captive and wild birds in Brazil. We found three different lineages of haemosporidia. Two lineages were identified as Plasmodium sp., one of which was previously detected in Europe and Asia, and the other is a new lineage closely related to P. gallinaceum. A new third lineage was identified as Haemoproteus sp. We found no significant differences in hematological and biochemical values between infected and non-infected birds, and the haemosporidian lineage did not seem to have an impact on the clinical and physiological parameters of A. jacutinga. This is the first report on an evaluation of natural haemosporidian infections diagnosed by microscopic and molecular methods in A. jacutinga by hematology, blood biochemistry, and serum protein values. Determining physiological parameters, occurrence and an estimation of the impact of haemosporidia in endangered avian species may contribute to the management of species rehabilitation and conservation.
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[Characterization of the assistance of a hematology unit].
Rev Bras Enferm
PUBLISHED: 12-30-2011
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This study aimed to describe the characteristics of service in a Hemotherapy Unit in the interior of the state of São Paulo in 2009. All ethical guidelines were followed and a survey was carried out in the database of the Unit. During the observed period, the Unit shows greater rate of repetition donors, with low levels of adverse reactions and 100% of donors satisfaction. The units of clinical medicine and intensive therapy were the sectors with highest consumption of transfusions at the hospital service. The described unit is self-sufficient at managing its resources. The present study shows the need to explore the dimensions of the professional roles in hemotherapy, the possibilities of finding new donors, the reasons that lead patients to donate blood, characteristics, epidemiological profile and satisfaction of receptors.
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The influence of double flask investing on tooth displacement in dentures processed by microwave irradiation.
Gerodontology
PUBLISHED: 11-10-2011
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This study evaluated the influence of the bimaxillary flask (BMF) and two different investing materials on first molar inclination in dentures processed by microwave irradiation.
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Whole-genome sequence of Corynebacterium pseudotuberculosis PAT10 strain isolated from sheep in Patagonia, Argentina.
J. Bacteriol.
PUBLISHED: 11-01-2011
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In this work, we report the complete genome sequence of a Corynebacterium pseudotuberculosis PAT10 isolate, collected from a lung abscess in an Argentine sheep in Patagonia, whose pathogen also required an investigation of its pathogenesis. Thus, the analysis of the genome sequence offers a means to better understanding of the molecular and genetic basis of virulence of this bacterium.
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A finite element approach for modeling micro-structural discontinuities in the heart.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 08-29-2011
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The presence of connective tissue as well as interstitial clefts forms a natural barrier to the electrical propagation in the heart. At a microscopic scale, such uncoupling structures change the pattern of the electrical conduction from uniform towards complex and may play a role in the genesis of cardiac arrhythmias. The anatomical diversity of conduction structures and their topology at a microscopic size scale is overwhelming for experimental techniques. Mathematical models have been often employed to study the behavior of the electrical propagation at a sub-cellular level. However, very fine and computationally expensive meshes are required to capture all microscopic details found in the cardiac tissue. In this work, we present a numerical technique based on the finite element method which allows to reproduce the effects of microscopic conduction barriers caused by the presence of uncoupling structures without actually resolving these structures in a high resolution mesh, thereby reducing the computational costs significantly.
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Evaluation in broilers of the probiotic properties of Pichia pastoris and a recombinant P. pastoris containing the Clostridium perfringens alpha toxin gene.
Vet. Microbiol.
PUBLISHED: 08-17-2011
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The probiotic properties of Pichia pastoris and of a recombinant P. pastoris containing the Clostridium perfringens alpha toxin gene were evaluated in broilers. One-day-old chicks randomly divided in four groups were fed with commercial feed devoid of antibacterials. The control group (1) received plain food, while the other groups were supplemented with either P. pastoris (2), the recombinant P. pastoris (3) or Bacillus cereus var. Toyoi (4). At day 49, live weights, feed efficiency and seroconversions were higher (P<0.05) in the supplemented groups than in the control groups. Group 3 showed the best results, while group 2 had lower weight gain than groups 3 and 4 although food conversion was better than in group 4. Seroconversions were not different (P>0.05) among the supplemented groups. Adverse reactions were not observed in histopathologic evaluation. We concluded that P. pastoris and the recombinant P. pastoris could be used as probiotics in broilers.
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Development of a chromatographic low pressure flow injection system: application to the analysis of methylxanthines in coffee.
Anal. Chim. Acta
PUBLISHED: 07-25-2011
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In this work, the coupling of a commercial monolithic column to a traditional low pressure FIA system is proposed for the analysis of theobromine, theophylline and caffeine in coffee brewed samples using UV detection. The parameters mobile phase composition, flow rate and loop volume were evaluated and discussed considering the various chromatographic parameters in order to enable resolution of the methylxanthines studied within the coffee brewed sample matrix. The analyses of methylxanthines in coffee brewed samples by the proposed methodology were in good agreement with those obtained by the reference procedure based on HPLC. Relative errors were below 6% for all samples analyzed. Detection limits in the selected experimental conditions were within 10(-6)M range for theobromine and theophylline, and 10(-5) M for caffeine. The determination rate of the three methylxanthines for coffee brewed samples was ca of 10 h(-1). The main advantage of the proposed flow system was the possibility to perform chromatographic separations in low pressure flow systems. This substantial improvement was achieved due to the compatibility of monolithic columns within the flow injection system surpassing in this way one of the main handicaps of traditional flow analysis systems. Additional features of the strategy presented were low cost, efficiency, high versatility and low reagent consumption comparing to HPLC methodologies usually followed in the case study herein presented.
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Hand hygiene, and not ertapenem use, contributed to reduction of carbapenem-resistant Pseudomonas aeruginosa rates.
Infect Control Hosp Epidemiol
PUBLISHED: 05-12-2011
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To evaluate the impact of ertapenem use in Pseudomonas aeruginosa carbapenem resistance, taking into account the volume of antimicrobial consumption, the consumption by the entire hospital of alcohol-based antiseptic hand rub, and the density rate of invasive practices.
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Morinda citrifolia Linn leaf extract possesses antioxidant activities and reduces nociceptive behavior and leukocyte migration.
J Med Food
PUBLISHED: 05-06-2011
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Herbal drugs have been used since ancient times to treat a wide range of diseases. Morinda citrifolia Linn (popularly known as "Noni") has been used in folk medicine by Polynesians for over 2,000 years. It is reported to have a broad range of therapeutic effects, including effects against headache, fever, arthritis, gingivitis, respiratory disorders, infections, tuberculosis, and diabetes. The aim of this study was to investigate the antioxidant, anti-inflammatory, antinociceptive, and antibacterial properties of the aqueous extract from M. citrifolia leaves (AEMC). Antioxidant activity was observed against lipid peroxidation, nitric oxide, and hydroxyl radicals. The antinociceptive effect of AEMC was observed in the acetic acid-induced writhing test at the higher dose. Moreover, AEMC significantly reduced the leukocyte migration in doses of 200 and 400 mg/kg and showed mild antibacterial activity. Together, the results suggest that properties of M. citrifolia leaf extract should be explored further in order to achieve newer tools for managing painful and inflammation conditions, including those related to oxidant states.
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Influences of cadmium on fine structure and metabolism of Hypnea musciformis (Rhodophyta, Gigartinales) cultivated in vitro.
Protoplasma
PUBLISHED: 05-04-2011
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The in vitro effect of cadmium on apical segments of Hypnea musciformis was examined. Over a period of 7 days, the segments were cultivated with different concentrations of cadmium, ranging from 50 to 300 ?M. The samples were processed for microscopic and histochemical analysis of growth rates, content of photosynthetic pigments, and photosynthetic performance. Cadmium treatments increased cell wall thickness and the accumulation of plastoglobuli. Destruction of chloroplast internal organization was observed. Compared to controls, algae exposed to cadmium showed growth rate reduction, depigmentation, and blending in the lateral branches. The content of photosynthetic pigments, including chlorophyll a and phycobiliproteins, decreased after exposure to different concentrations of cadmium. These results agree with the decreased photosynthetic performance and relative electron transport rate observed after exposure of algae to cadmium. Taken together, these findings strongly indicate that cadmium negatively affects the architecture and metabolism of the carragenophyte H. musciformis, thus posing a threat to the economic vitality of this red macroalgae.
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Caudal septoplasty: efficacy of a surgical technique-preliminary report.
Braz J Otorhinolaryngol
PUBLISHED: 05-04-2011
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Although not being the most frequent nasal septal deviations, those of the caudal septum account for many complaints. The correction of such defects has always been the subject of much controversy, and several different operative techniques have been described.
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Endoscopic treatment of esthesioneuroblastoma.
Braz J Otorhinolaryngol
PUBLISHED: 05-04-2011
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Esthesioneuroblastoma is an uncommon malignant tumor of the nasal vault. Treatment consists of craniofacial resection. As endoscopic techniques have advanced, this approach has been recommended to avoid morbidity and to reduce costs.
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Acinetobacter soli as a cause of bloodstream infection in a neonatal intensive care unit.
J. Clin. Microbiol.
PUBLISHED: 04-27-2011
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Acinetobacter soli is a new bacterial species described from forest soil. Five cases of bloodstream infection caused by A. soli clonal isolates are reported here for the first time. The patients were neonates admitted to an intensive care unit. This is a new neonatal pathogen with the potential to cause outbreaks.
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Effect of bleaching gels on surface roughness of nanofilled composite resins.
Eur J Dent
PUBLISHED: 04-16-2011
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The aim of this study was to investigate the superficial texture of composite restorations after different bleaching protocols.
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[Hormonal control of pituitary adenomas by transsphenoidal surgery: results of the first five years of experience].
Arq Bras Endocrinol Metabol
PUBLISHED: 04-07-2011
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To evaluate the initial results of a surgical team in the hormonal control of secreting pituitary adenomas.
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Ehrlichiosis in Brazil.
Rev Bras Parasitol Vet
PUBLISHED: 03-29-2011
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Ehrlichiosis is a disease caused by rickettsial organisms belonging to the genus Ehrlichia. In Brazil, molecular and serological studies have evaluated the occurrence of Ehrlichia species in dogs, cats, wild animals and humans. Ehrlichia canis is the main species found in dogs in Brazil, although E. ewingii infection has been recently suspected in five dogs. Ehrlichia chaffeensis DNA has been detected and characterized in mash deer, whereas E. muris and E. ruminantium have not yet been identified in Brazil. Canine monocytic ehrlichiosis caused by E. canis appears to be highly endemic in several regions of Brazil, however prevalence data are not available for several regions. Ehrlichia canis DNA also has been detected and molecularly characterized in three domestic cats, and antibodies against E. canis were detected in free-ranging Neotropical felids. There is serological evidence suggesting the occurrence of human ehrlichiosis in Brazil but its etiologic agent has not yet been established. Improved molecular diagnostic resources for laboratory testing will allow better identification and characterization of ehrlichial organisms associated with human ehrlichiosis in Brazil.
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Disseminated Histoplasma capsulatum and Cryptococcus neoformans co-infection in patients with AIDS.
Mycopathologia
PUBLISHED: 03-23-2011
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Histoplasmosis and cryptococcosis are the most prevalent systemic mycoses in HIV-infected patients. The authors report a 20-year-old Brazilian HIV-positive woman with concomitant disseminated histoplasmosis and cryptococcosis. In addition, we review the reported cases described in the medical literature.
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Evaluation of the return rate of volunteer blood donors.
Rev Bras Hematol Hemoter
PUBLISHED: 03-09-2011
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To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services.
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Alterations in architecture and metabolism induced by ultraviolet radiation-B in the carragenophyte Chondracanthus teedei (Rhodophyta, Gigartinales).
Protoplasma
PUBLISHED: 02-28-2011
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The in vivo effect of ultraviolet radiation-B (UVBR) in apical segments of Chondracanthus teedei was examined. Over a period of 7 days, the segments were cultivated and exposed to photosynthetically active radiation (PAR) at 80 ?mol photons m(-2) s(-1) and PAR?+?UVBR at 1.6 W?m(-2) for 3 h per day. The samples were processed for electron microscopy and histochemistry; also was analyzed growth rates, mitochondrial activity, protein levels, content of photosynthetic pigments and photosynthetic performance. UVBR elicited increased cell wall thickness and accumulation of plastoglobuli, changes in mitochondrial organization and destruction of chloroplast internal organization. Compared to controls, algae exposed to PAR?+?UVBR showed a growth rate reduction of 55%. The content of photosynthetic pigments, including chlorophyll a and phycobiliproteins, decreased after exposure to PAR?+?UVBR. This result agrees with the decreased photosynthetic performance observed after exposing algae to PAR?+?UVBR. Irradiation also elicited increased activity of the antioxidant enzyme glutathione peroxidase and decreased mitochondrial NADH dehydrogenase activity, which correlated with the decreased protein content in plants exposed to PAR?+?UVBR. Taken together, these findings strongly indicate that UVBR negatively affects the architecture and metabolism of the carragenophyte C. teedei.
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[Nosocomial sinusitis in an intensive care unit: a microbiological study].
Braz J Otorhinolaryngol
PUBLISHED: 02-23-2011
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Nosocomial sinusitis is a common complication of patients in ICUs. Its diagnosis is important, and early treatment is required to avoid serious complications such as pneumonia, sepsis, meningitis, and intracranial abscesses.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.