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Find video protocols related to scientific articles indexed in Pubmed.
Mutagenic and antimutagenic effects of Heterotheca inuloides.
Sci Rep
PUBLISHED: 06-09-2014
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The antioxidant and hepatoprotective effects of Heterotheca inuloides have been reported before, nevertheless its use as a possible chemopreventive agent has not been documented. The aim of this study was to evaluate the mutagenic and antimutagenic activities of H. inuloides extracts using the Ames test. Both, the methanolic and acetonic extracts, were mutagenic in the TA98 but not in TA100 or TA102 strains. On the other hand, the methanolic extract reduced the mutagenicity of norfloxacin, benzo[a]pyrene and 2-aminoanthracene. Quercetin, one of the main components in the methanolic extract, also presented a mutagenic/antimutagenic dual effect and is an inhibitor of Cytochrome P450 (CYP) 1A. The antigenotoxic properties of H. inuloides could be due to the antioxidant properties previously reported and to its CYP inhibitory effect mediated by quercetin. Further studies with in vivo systems will afford information about H. inuloides beneficial and detrimental properties.
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Cross-cultural adaptation and validation of the spanish version of the performance enhancement attitude scale (petróczi, ).
J Sports Sci Med
PUBLISHED: 05-01-2014
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The aim of the present study was to cross-culturally adapt and validate the Spanish version of the Performance Enhancement Attitude Scale (PEAS). A cross-sectional multi-sample survey with 17 independent datasets was carried out. Cross-cultural adaptation of the PEAS into Spanish was conducted through forward/backward translations, consensus panels and comparative analyses of known-groups to establish evidence for its reliability and validity. Weighted Kappa coefficients with quadratic weighting were used to assess the reliability of each item, with Cronbach's internal consistency coefficients for overall scale's reliability and Spearman's correlation coefficient for test-retest reliability over a one-week period. Confirmatory factor analysis (CFA) was performed to assess the scale's structure. Differences between self-admitted doping users and non-users were analysed to verify the PEAS' construct validity in 8 datasets. Spearman's correlation coefficient was also used to assess the relationships between the PEAS and self-esteem, self-efficacy and perceived descriptive norm to establish convergent validity. The scale showed satisfactory levels of internal consistency (? = 0.71-0.85), reliability of each item (Kappa values range 0.34-0.64) and temporal stability (r = 0.818; p < 0.001). CFA showed acceptable fit (RMSEA <0.08, mean RMSEA = 0.055; ?(2)/df < 3, mean ?(2)/df = 1.89) for all but one samples. As expected, self-admitted doping users showed more positive attitude toward doping than non-users. Significant and strong negative relationship was found between PEAS and self-efficacy; weak negative correlation with self-esteem and and positive correlation with perceived descriptive norm. The Spanish version of PEAS showed satisfactory psychometric properties. Considerations for application and improvement are outlined. Key pointsFirst study that crosses culturally adapted the PEAS to the Spanish language.The Spanish version of PEAS has satisfactory psychometric properties.Users scored higher than non-users indicating a satisfactory construct validity. Significant positive correlation was found between PEAS and projected use.Significant negative correlation between PEAS and self-esteem and self-efficacy.
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Expanding the mutation spectrum in 182 Spanish probands with craniosynostosis: identification and characterization of novel TCF12 variants.
Eur. J. Hum. Genet.
PUBLISHED: 04-23-2014
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Craniosynostosis, caused by the premature fusion of one or more of the cranial sutures, can be classified into non-syndromic or syndromic and by which sutures are affected. Clinical assignment is a difficult challenge due to the high phenotypic variability observed between syndromes. During routine diagnostics, we screened 182 Spanish craniosynostosis probands, implementing a four-tiered cascade screening of FGFR2, FGFR3, FGFR1, TWIST1 and EFNB1. A total of 43 variants, eight novel, were identified in 113 (62%) patients: 104 (92%) detected in level 1; eight (7%) in level 2 and one (1%) in level 3. We subsequently screened additional genes in the probands with no detected mutation: one duplication of the IHH regulatory region was identified in a patient with craniosynostosis Philadelphia type and five variants, four novel, were identified in the recently described TCF12, in probands with coronal or multisuture affectation. In the 19 Saethre-Chotzen syndrome (SCS) individuals in whom a variant was detected, 15 (79%) carried a TWIST1 variant, whereas four (21%) had a TCF12 variant. Thus, we propose that TCF12 screening should be included for TWIST1 negative SCS patients and in patients where the coronal suture is affected. In summary, a molecular diagnosis was obtained in a total of 119/182 patients (65%), allowing the correct craniosynostosis syndrome classification, aiding genetic counselling and in some cases provided a better planning on how and when surgical intervention should take place and, subsequently the appropriate clinical follow up.European Journal of Human Genetics advance online publication, 1 October 2014; doi:10.1038/ejhg.2014.205.
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Unobtrusive augmentation of critical hidden structures in laparoscopy.
Stud Health Technol Inform
PUBLISHED: 04-16-2014
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A fundamental problem in implementing augmented reality (AR) surgery is characterizing how visualizations effect surgeon perception. This problem is important because procedure outcomes depend on surgeon ability to perceive hidden and visible structure interrelation which may be quite dynamic. AR techniques such as x-ray vision are designed to compensate for or reintroduce depth cues lost overlaying hidden structures on a view stream. Such enhancements are necessarily deviations, which may obtrude. This paper provides discussion of hidden structure rendering, analysis, a proposed framework, protocol and experiment (n=2500) for safe evaluation within in vitro laparoscopic video from, and minimal transfer to, in vivo surgery. Results evidence our protocol enables comparison of hidden structure visualizations on task efficacy in vitro and suggest promising new direction towards validating AR in live surgery.
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Observation of quantum-tunnelling-modulated spin texture in ultrathin topological insulator Bi2Se3 films.
Nat Commun
PUBLISHED: 04-09-2014
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Understanding the spin-texture behaviour of boundary modes in ultrathin topological insulator films is critically essential for the design and fabrication of functional nanodevices. Here, by using spin-resolved photoemission spectroscopy with p-polarized light in topological insulator Bi2Se3 thin films, we report tunnelling-dependent evolution of spin configuration in topological insulator thin films across the metal-to-insulator transition. We report a systematic binding energy- and wavevector-dependent spin polarization for the topological surface electrons in the ultrathin gapped-Dirac-cone limit. The polarization decreases significantly with enhanced tunnelling realized systematically in thin insulating films, whereas magnitude of the polarization saturates to the bulk limit faster at larger wavevectors in thicker metallic films. We present a theoretical model that captures this delicate relationship between quantum tunnelling and Fermi surface spin polarization. Our high-resolution spin-based spectroscopic results suggest that the polarization current can be tuned to zero in thin insulating films forming the basis for a future spin-switch nanodevice.
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A reproducible ex vivo model for transanal minimally invasive surgery.
JSLS
PUBLISHED: 04-01-2014
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Rectal tumors can be excised through a number of minimally invasive transanal techniques including transanal excision, transanal endoscopic microsurgery, and transanal minimally invasive surgery (TAMIS). Specialty training is often required to master the nuances of these approaches. This study aimed to create a reproducible transanal excision training model that is suited for laparoendoscopic techniques.
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Rotated domain network in graphene on cubic-SiC(001).
Nanotechnology
PUBLISHED: 03-04-2014
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The atomic structure of the cubic-SiC(001) surface during ultra-high vacuum graphene synthesis has been studied using scanning tunneling microscopy (STM) and low-energy electron diffraction. Atomically resolved STM studies prove the synthesis of a uniform, millimeter-scale graphene overlayer consisting of nanodomains rotated by ±13.5° relative to the left angle bracket 110 right angle bracket-directed boundaries. The preferential directions of the domain boundaries coincide with the directions of carbon atomic chains on the SiC(001)-c(2 × 2) reconstruction, fabricated prior to graphene synthesis. The presented data show the correlation between the atomic structures of the SiC(001)-c(2 × 2) surface and the graphene/SiC(001) rotated domain network and pave the way for optimizing large-area graphene synthesis on low-cost cubic-SiC(001)/Si(001) wafers.
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Anisotropic two-dimensional electron gas at SrTiO3(110).
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 03-03-2014
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Two-dimensional electron gases (2DEGs) at oxide heterostructures are attracting considerable attention, as these might one day substitute conventional semiconductors at least for some functionalities. Here we present a minimal setup for such a 2DEG--the SrTiO3(110)-(4 × 1) surface, natively terminated with one monolayer of tetrahedrally coordinated titania. Oxygen vacancies induced by synchrotron radiation migrate underneath this overlayer; this leads to a confining potential and electron doping such that a 2DEG develops. Our angle-resolved photoemission spectroscopy and theoretical results show that confinement along (110) is strikingly different from the (001) crystal orientation. In particular, the quantized subbands show a surprising "semiheavy" band, in contrast with the analog in the bulk, and a high electronic anisotropy. This anisotropy and even the effective mass of the (110) 2DEG is tunable by doping, offering a high flexibility to engineer the properties of this system.
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Investigation of a food-borne Salmonella Oranienburg outbreak in a Mexican prison.
J Infect Dev Ctries
PUBLISHED: 02-13-2014
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Gastroenteritis outbreaks in prisons represent a public health risk worldwide. Identifying and characterizing the etiological agents of gastroenteritis outbreaks in prisons is important for implementing effective prevention and infection control measures. We present the first studied case of a gastroenteritis outbreak in a Mexican prison.
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Pharmacokinetic modeling of enterohepatic circulation of mycophenolic acid in renal transplant recipients.
Kidney Int.
PUBLISHED: 01-08-2014
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Several factors contribute to mycophenolic acid (MPA) between-patient variability. Here we characterize the metabolic pathways of MPA and quantify the effect of combining genetic polymorphism of multidrug-resistant-associated protein-2, demographics, biochemical covariates, co-medication (cyclosporine (CsA) vs. macrolides), and renal function on MPA, 7-O-MPA-glucuronide (MPAG), and acyl-glucuronide (AcMPAG) disposition, in renal transplant recipients, after mycophenolate mofetil. Complete pharmacokinetic profiles from 56 patients (five occasions) were analyzed. Enterohepatic circulation was modeled by transport of MPAG to the absorption site. This transport significantly decreased with increasing CsA trough concentrations (CtroughCsA). MPAG and AcMPAG plasma clearances significantly decreased with renal function. No significant influence of multidrug-resistant-associated protein-2 C24T single-nucleotide polymorphism was found. The model adequately predicted the increase in MPAG/AcMPAG exposures in CsA and macrolide patients with decreased renal function. This resulted in higher MPA exposures in macrolide patients versus CsA patients, and increased MPA exposures with renal function from 25 to 10?ml/min, in macrolide patients, owing to enhanced MPAG enterohepatic circulation. Lower-percentage enterohepatic circulation occurred with higher CtroughCsA and renal function values. The lack of MPA protein-binding modeling did not permit evaluation of the impact of renal function and CtroughCsA on MPA exposures in CsA patients. Thus, dose tailoring of covariates is recommended for target MPA exposure.
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Virtual environments for the transfer of navigation skills in the blind: a comparison of directed instruction vs. video game based learning approaches.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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For profoundly blind individuals, navigating in an unfamiliar building can represent a significant challenge. We investigated the use of an audio-based, virtual environment called Audio-based Environment Simulator (AbES) that can be explored for the purposes of learning the layout of an unfamiliar, complex indoor environment. Furthermore, we compared two modes of interaction with AbES. In one group, blind participants implicitly learned the layout of a target environment while playing an exploratory, goal-directed video game. By comparison, a second group was explicitly taught the same layout following a standard route and instructions provided by a sighted facilitator. As a control, a third group interacted with AbES while playing an exploratory, goal-directed video game however, the explored environment did not correspond to the target layout. Following interaction with AbES, a series of route navigation tasks were carried out in the virtual and physical building represented in the training environment to assess the transfer of acquired spatial information. We found that participants from both modes of interaction were able to transfer the spatial knowledge gained as indexed by their successful route navigation performance. This transfer was not apparent in the control participants. Most notably, the game-based learning strategy was also associated with enhanced performance when participants were required to find alternate routes and short cuts within the target building suggesting that a ludic-based training approach may provide for a more flexible mental representation of the environment. Furthermore, outcome comparisons between early and late blind individuals suggested that greater prior visual experience did not have a significant effect on overall navigation performance following training. Finally, performance did not appear to be associated with other factors of interest such as age, gender, and verbal memory recall. We conclude that the highly interactive and immersive exploration of the virtual environment greatly engages a blind user to develop skills akin to positive near transfer of learning. Learning through a game play strategy appears to confer certain behavioral advantages with respect to how spatial information is acquired and ultimately manipulated for navigation.
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Action video game play and transfer of navigation and spatial cognition skills in adolescents who are blind.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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For individuals who are blind, navigating independently in an unfamiliar environment represents a considerable challenge. Inspired by the rising popularity of video games, we have developed a novel approach to train navigation and spatial cognition skills in adolescents who are blind. Audio-based Environment Simulator (AbES) is a software application that allows for the virtual exploration of an existing building set in an action video game metaphor. Using this ludic-based approach to learning, we investigated the ability and efficacy of adolescents with early onset blindness to acquire spatial information gained from the exploration of a target virtual indoor environment. Following game play, participants were assessed on their ability to transfer and mentally manipulate acquired spatial information on a set of navigation tasks carried out in the real environment. Success in transfer of navigation skill performance was markedly high suggesting that interacting with AbES leads to the generation of an accurate spatial mental representation. Furthermore, there was a positive correlation between success in game play and navigation task performance. The role of virtual environments and gaming in the development of mental spatial representations is also discussed. We conclude that this game based learning approach can facilitate the transfer of spatial knowledge and further, can be used by individuals who are blind for the purposes of navigation in real-world environments.
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Does a non-circular chainring improve performance in the bicycle motocross cycling start sprint?
J Sports Sci Med
PUBLISHED: 01-01-2014
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Maximising power output during the initial acceleration phase of a bicycle motocross (BMX) race increases the chance to lead the group for the rest of the race. The purpose of this study was to investigate the effect of non-circular chainrings (Q-ring) on performance during the initial acceleration phase of a BMX race. Sixteen male cyclists (Spanish National BMX team) performed two counterbalanced and randomized initial sprints (3.95s), using Q- ring vs. circular chainring, on a BMX track. The sample was divided into two different groups according to their performance (Elite; n = 8 vs. Cadet; n = 8). Elite group covered a greater distance using Q-ring (+0.26 m, p = 0.02; D = 0.23), whilst the improvement for the Cadet (+0.04 m) was not significant (p = 0.87; D = -0.02). Also, there was no significant difference in power output for the Elite group, while the Cadet group revealed larger peak power with the circular chainring. Neither lactate level, nor heart rate showed significant differences due to the different chainring used. The non-circular chainring improved the initial acceleration capacity only in the Elite riders. Key PointsThis work provides novel results demonstrating very significant improvements in the sprint performance of BMX cycling discipline using a non-circular chainring system.This study seeks a practical application from scientific analysisAll data are obtained in a real context of high competition using a sample comprised by the National Spanish Team.Some variables influencing performance as subjects' physical fitness are discussed.Technical equipment approved by International Cycling Union is studied to check its potentially beneficial influence on performance.
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Fractional Modeling of the AC Large-Signal Frequency Response in Magnetoresistive Current Sensors.
Sensors (Basel)
PUBLISHED: 10-04-2013
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Fractional calculus is considered when derivatives and integrals of non-integer order are applied over a specific function. In the electrical and electronic domain, the transfer function dependence of a fractional filter not only by the filter order n, but additionally, of the fractional order ? is an example of a great number of systems where its input-output behavior could be more exactly modeled by a fractional behavior. Following this aim, the present work shows the experimental ac large-signal frequency response of a family of electrical current sensors based in different spintronic conduction mechanisms. Using an ac characterization set-up the sensor transimpedance function  is obtained considering it as the relationship between sensor output voltage and input sensing current,[PLEASE CHECK FORMULA IN THE PDF]. The study has been extended to various magnetoresistance sensors based in different technologies like anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), spin-valve (GMR-SV) and tunnel magnetoresistance (TMR). The resulting modeling shows two predominant behaviors, the low-pass and the inverse low-pass with fractional index different from the classical integer response. The TMR technology with internal magnetization offers the best dynamic and sensitivity properties opening the way to develop actual industrial applications.
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Sentinel lymph node biopsy for cutaneous melanoma: a 6 years study.
Indian J Plast Surg
PUBLISHED: 08-21-2013
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The aim of this study was to evaluate the results of sentinel lymph node biopsy (SLNB) in cutaneous melanoma at our institution.
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Treatment of refractory perianal fistulas with ligation of the intersphincteric fistula tract: preliminary results.
Am Surg
PUBLISHED: 07-03-2013
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Several surgical options exist for management of fistula in ano. The goal of treatment is to achieve closure of the fistula while maintaining continence. Sphincter-sparing operations to close perianal fistulas include advancement flap, anal fistula plug, fibrin glue, and fistulectomy. Variable success rates from 30 to 80 per cent have been reported. Ligation of intersphincteric fistula tract (LIFT), first described in 2007, has a reported success rate from 40 to 94 per cent. The objective of this study was to study our results of the LIFT procedure for refractory perianal fistulas. We conducted a retrospective 18-month review of consecutive patients with refractory perianal disease treated with the LIFT procedure at an academic, tertiary, colorectal practice. All patients undergoing a LIFT procedure for anal fistula from August 2010 to August 2012 were included in the study. The primary end points were success rates at 1 month and 3 months. Secondary end points were postoperative complications and maintenance of continence. Twenty patients underwent LIFT procedures of whom nine had previously failed treatments. Mean age was 45 years and included 12 male and eight female patients. Success rate at 1 month was 70 per cent (14 patients) and at 3 months was 80 per cent (16 patients). Success rates for patients with previously failed attempts were 67 per cent at 1 month and 89 per cent at 3 months. Continence was maintained in 100 per cent of patients. Our data support the use of the LIFT procedure for refractory perirectal fistulas.
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Robot-assisted rectopexy and colpopexy for rectal prolapse.
Int Urogynecol J
PUBLISHED: 06-27-2013
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This video demonstrates a technique for robot-assisted combined rectopexy with colpopexy, but without the use of mesh for rectal prolapse.
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Inadequate prescription of chronic consumption of proton pump inhibitors in a hospital in Mexico. Cross-sectional study.
Rev Esp Enferm Dig
PUBLISHED: 06-06-2013
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Introduction: PPIs have been an enormous therapeutic advance in acid-related diseases. However, it has been detected an abuse in its consumption. The aim of this study was to determine the frequency of inadequate prescription of chronic use of PPIs in outpatients in a speciality hospital.Material and methods: we performed a cross-sectional descriptive study review. The study population were patients, chronic users of proton pump inhibitors (PPIs), attending outpatient consult in a hospital of government workers. We defined as chronic user of PPIs that patient that takes medication daily for over a year and inappropriate prescription, that one that has not been approved by the clinical guidelines. A simple random sampling was utilized. The following parameters were investigated: diagnosis and prescription of PPIs, time of use, at which level of care PPIs were prescribed (primary care or specialist), self-medication, with or without endoscopy. Forthe statistical analysis, we used Student´s t-test and Chi-square, 95 % confidence intervals and significance 0.05 %.Results: we reviewed 153 patients, 40 (26.1 %) men and 113 (73.9 %) women, mean age 58 ± 11.4 years. The prescription of chronic treatment with PPIs was adequate in 64.7 % of patients and inadequate in 35.3 %. The most common appropriate prescription (31.3 %) of chronic use of PPIs was due to gastroesophageal reflux disease. The most common inadequate prescription was absence of diagnosis (22.2 %), polypharmacy without nonsteroidal anti-inflammatory drugs (16.6 %) and chronic gastritis (16.6 %). History of endoscopy were not statistically significant.Conclusions: the frequency of inappropriate prescriptions of chronic use of PPIs was high, around 35.3 %, similar to those reported in hospitals in developed countries.
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Negligible surface reactivity of topological insulators Bi2Se3 and Bi2Te3 towards oxygen and water.
ACS Nano
PUBLISHED: 05-30-2013
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The long-term stability of functional properties of topological insulator materials is crucial for the operation of future topological insulator based devices. Water and oxygen have been reported to be the main sources of surface deterioration by chemical reactions. In the present work, we investigate the behavior of the topological surface states on Bi2X3 (X = Se, Te) by valence-band and core level photoemission in a wide range of water and oxygen pressures both in situ (from 10(-8) to 0.1 mbar) and ex situ (at 1 bar). We find that no chemical reactions occur in pure oxygen and in pure water. Water itself does not chemically react with both Bi2Se3 and Bi2Te3 surfaces and only leads to slight p-doping. In dry air, the oxidation of the Bi2Te3 surface occurs on the time scale of months, in the case of Bi2Se3 surface of cleaved crystal, not even on the time scale of years. The presence of water, however, promotes the oxidation in air, and we suggest the underlying reactions supported by density functional calculations. All in all, the surface reactivity is found to be negligible, which allows expanding the acceptable ranges of conditions for preparation, handling and operation of future Bi2X3-based devices.
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Development of an audio-based virtual gaming environment to assist with navigation skills in the blind.
J Vis Exp
PUBLISHED: 04-10-2013
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Audio-based Environment Simulator (AbES) is virtual environment software designed to improve real world navigation skills in the blind. Using only audio based cues and set within the context of a video game metaphor, users gather relevant spatial information regarding a buildings layout. This allows the user to develop an accurate spatial cognitive map of a large-scale three-dimensional space that can be manipulated for the purposes of a real indoor navigation task. After game play, participants are then assessed on their ability to navigate within the target physical building represented in the game. Preliminary results suggest that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building as indexed by their performance on a series of navigation tasks. These tasks included path finding through the virtual and physical building, as well as a series of drop off tasks. We find that the immersive and highly interactive nature of the AbES software appears to greatly engage the blind user to actively explore the virtual environment. Applications of this approach may extend to larger populations of visually impaired individuals.
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Platelet-activating factor nasal challenge induces nasal congestion and reduces nasal volume in both healthy volunteers and allergic rhinitis patients.
Am J Rhinol Allergy
PUBLISHED: 04-09-2013
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Platelet-activating factor (PAF) is a lipid mediator produced by most inflammatory cells. Clinical and experimental findings suggest that PAF participates in allergic rhinitis (AR) pathogenesis. The aim was to assess the PAF ability to induce clinical response in nasal airway after local stimulation.
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Doping in sport: a review of elite athletes attitudes, beliefs, and knowledge.
Sports Med
PUBLISHED: 03-28-2013
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Doping in sport is a well-known phenomenon that has been studied mainly from a biomedical point of view, even though psychosocial approaches are also key factors in the fight against doping. This phenomenon has evolved greatly in recent years, and greater understanding of it is essential for developing efficient prevention programmes. In the psychosocial approach, attitudes are considered an index of doping behaviour, relating the use of banned substances to greater leniency towards doping. The aim of this review is to gather and critically analyse the most recent publications describing elite athletes attitudes, beliefs and knowledge of doping in sport, to better understand the foundations provided by the previous work, and to help develop practical strategies to efficiently combat doping. For this purpose, we performed a literature search using combinations of the terms "doping", "sport", "elite athletes", "attitudes", "beliefs", "knowledge", "drugs", and "performance-enhancing substances" (PES). A total of 33 studies were subjected to comprehensive assessment using articles published between 2000 and 2011. All of the reports focused on elite athletes and described their attitudes, beliefs and knowledge of doping in sport. The initial reasons given for using banned substances included achievement of athletic success by improving performance, financial gain, improving recovery and prevention of nutritional deficiencies, as well as the idea that others use them, or the "false consensus effect". Although most athletes acknowledge that doping is cheating, unhealthy and risky because of sanctions, its effectiveness is also widely recognized. There is a general belief about the inefficacy of anti-doping programmes, and athletes criticise the way tests are carried out. Most athletes consider the severity of punishment is appropriate or not severe enough. There are some differences between sports, as team-based sports and sports requiring motor skills could be less influenced by doping practices than individual self-paced sports. However, anti-doping controls are less exhaustive in team sports. The use of banned substance also differs according to the demand of the specific sport. Coaches appear to be the main influence and source of information for athletes, whereas doctors and other specialists do not seem to act as principal advisors. Athletes are becoming increasingly familiar with anti-doping rules, but there is still a lack of knowledge that should be remedied using appropriate educational programmes. There is also a lack of information on dietary supplements and the side effects of PES. Therefore, information and prevention are necessary, and should cater to the athletes and associated stakeholders. This will allow us to establish and maintain correct attitudes towards doping. Psychosocial programmes must be carefully planned and developed, and should include middle- to long-term objectives (e.g. changing attitudes towards doping and the doping culture). Some institutions have developed or started prevention or educational programmes without the necessary resources, while the majority of the budget is spent on anti-doping testing. Controls are obviously needed, as well as more efficient educational strategies. Therefore, we encourage sporting institutions to invest in educational programmes aimed at discouraging the use of banned substances. Event organizers and sport federations should work together to adapt the rules of each competition to disincentivize dopers. Current research methods are weak, especially questionnaires. A combination of qualitative and quantitative measurements are recommended, using interviews, questionnaires and, ideally, biomedical tests. Studies should also examine possible geographical and cultural differences in attitudes towards doping.
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Role of Art v 3 in pollinosis of patients allergic to Pru p 3.
J. Allergy Clin. Immunol.
PUBLISHED: 03-06-2013
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Food allergy caused by lipid transfer protein (LTP) from peach (Pru p 3) is frequently associated with sensitization to mugwort LTP (Art v 3). Although in vitro cross-reactivity is already well known, it has yet to be elucidated whether a pollen LTP can induce rhinitis.
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Comparison of results of combined liver-kidney transplantation vs. isolated liver transplantation.
Ann Hepatol
PUBLISHED: 02-12-2013
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Combined liver-kidney transplantation (LKT) is the best therapeutic option for patients with end-stage liver and kidney disease.
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Real world navigation independence in the early blind correlates with differential brain activity associated with virtual navigation.
Hum Brain Mapp
PUBLISHED: 01-25-2013
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Navigating is a complex cognitive task that places high demands on spatial abilities, particularly in the absence of sight. Significant advances have been made in identifying the neural correlates associated with various aspects of this skill; however, how the brain is able to navigate in the absence of visual experience remains poorly understood. Furthermore, how neural network activity relates to the wide variability in navigational independence and skill in the blind population is also unknown. Using functional magnetic resonance imaging, we investigated the neural correlates of audio-based navigation within a large scale, indoor virtual environment in early profoundly blind participants with differing levels of spatial navigation independence (assessed by the Santa Barbara Sense of Direction scale). Performing path integration tasks in the virtual environment was associated with activation within areas of a core network implicated in navigation. Furthermore, we found a positive relationship between Santa Barbara Sense of Direction scores and activation within right temporal parietal junction during the planning and execution phases of the task. These findings suggest that differential navigational ability in the blind may be related to the utilization of different brain network structures. Further characterization of the factors that influence network activity may have important implications regarding how this skill is taught in the blind community. Hum Brain Mapp, 2013. © 2013 Wiley Periodicals, Inc.
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Preconditioning with hemin decreases Plasmodium chabaudi adami parasitemia and inhibits erythropoiesis in BALB/c mice.
PLoS ONE
PUBLISHED: 01-24-2013
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Increased susceptibility to bacterial and viral infections and dysfunctional erythropoiesis are characteristic of malaria and other hemolytic hemoglobinopathies. High concentrations of free heme are common in these conditions but little is known about the effect of heme on adaptive immunity and erythropoiesis. Herein, we investigated the impact of heme (hemin) administration on immune parameters and steady state erythropoiesis in BALB/c mice, and on parasitemia and anemia during Plasmodium chabaudi adami infection. Intra-peritoneal injection of hemin (5 mg/Kg body weight) over three consecutive days decreased the numbers of splenic and bone marrow macrophages, IFN-? responses to CD3 stimulation and T(h)1 differentiation. Our results show that the numbers of erythroid progenitors decreased in the bone marrow and spleen of mice treated with hemin, which correlated with reduced numbers of circulating reticulocytes, without affecting hemoglobin concentrations. Although blunted IFN-? responses were measured in hemin-preconditioned mice, the mice developed lower parasitemia following P.c.adami infection. Importantly, anemia was exacerbated in hemin-preconditioned mice with malaria despite the reduced parasitemia. Altogether, our data indicate that free heme has dual effects on malaria pathology.
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Low-Bone-Mass Phenotype of Deficient Mice for the Cluster of Differentiation 36 (CD36).
PLoS ONE
PUBLISHED: 01-01-2013
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Bone tissue is continuously remodeled by bone cells and maintenance of its mass relies on the balance between the processes of resorption and formation. We have reported the expression of numerous scavenger receptors, namely scavenger receptor (SR) class B type I and II (SR-BI and SR-BII), and CD36, in bone-forming osteoblasts but their physiological roles in bone metabolism are still unknown. To unravel the role of CD36 in bone metabolism, we determined the bone phenotype of CD36 knockout (CD36KO) mice and characterized the cell functions of osteoblasts lacking CD36. Weights of CD36KO mice were significantly lower than corresponding wild-type (WT) mice, yet no significant difference was found in femoral nor tibial length between CD36KO and WT mice. Analysis of bone architecture by micro-computed tomography revealed a low bone mass phenotype in CD36KO mice of both genders. Femoral trabecular bone from 1 to 6 month-old CD36KO mice showed lower bone volume, higher trabecular separation and reduced trabeculae number compared to WT mice; similar alterations were noticed for lumbar vertebrae. Plasma levels of osteocalcin (OCN) and N-terminal propeptide of type I procollagen (PINP), two known markers of bone formation, were significantly lower in CD36KO mice than in WT mice, whereas plasma levels of bone resorption markers were similar. Accordingly, histology highlighted lower osteoblast perimeter and reduced bone formation rate. In vitro functional characterization of bone marrow stromal cells and osteoblasts isolated from CD36KO mice showed reduced cell culture expansion and survival, lower gene expression of osteoblastic Runt-related transcription factor 2 (Runx2) and osterix (Osx), as well as bone sialoprotein (BSP) and osteocalcin (OCN). Our results indicate that CD36 is mandatory for adequate bone metabolism, playing a role in osteoblast functions ensuring adequate bone formation.
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Attitudes towards doping and related experience in Spanish national cycling teams according to different Olympic disciplines.
PLoS ONE
PUBLISHED: 01-01-2013
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Attitudes towards doping are considered an influence of doping intentions. The aims of the present study were 1) to discover and compare the attitudes towards doping among Spanish national team cyclists from different Olympic disciplines, as well as 2) to get some complementary information that could better explain the context. The sample was comprised of seventy-two cyclists: mean age 19.67±4.72 years; 70.8% males (n?=?51); from the different Olympic disciplines of Mountain bike -MTB- (n?=?18), Bicycle Moto Cross -BMX- (n?=?12), Track -TRA- (n?=?9) and Road -ROA- (n?=?33). Descriptive design was carried out using a validated scale (PEAS). To complement this, a qualitative open-ended questionnaire was used. Overall mean score (17-102) was 36.12±9.39. For different groups, the data were: MTB: 30.28±6.92; BMX: 42.46±10.74; TRA: 43.22±12.00; ROA: 34.91±6.62, respectively. In relation to overall score, significant differences were observed between MTB and BMX (p?=?0.002) and between MTB and TRA (p?=?0.003). For the open-ended qualitative questionnaire, the most mentioned word associated with "doping" was "cheating" (48.83% of total sample), with "responsible agents of doping" the word "doctor" (52,77%), and with the "main reason for the initiation in doping" the words "sport achievement" (45.83%). The major proposed solution was "doing more doping controls" (43.05%). Moreover, 48.67% stated that there was "a different treatment between cycling and other sports". This study shows that Spanish national team cyclists from Olympic cycling disciplines, in general, are not tolerant in relation to doping. BMX and Track riders are a little more permissive towards the use of banned substances than MTB and Road. Results from the qualitative open-ended questionnaire showed interesting data in specific questions. These results empower the idea that, apart from maintaining doping controls and making them more efficient, anti-doping education programs are needed from the earliest ages.
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Combined anaerobic ammonium and methane oxidation for nitrogen and methane removal.
Biochem. Soc. Trans.
PUBLISHED: 11-23-2011
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Anammox (anaerobic ammonium oxidation) is an environment-friendly and cost-efficient nitrogen-removal process currently applied to high-ammonium-loaded wastewaters such as anaerobic digester effluents. In these wastewaters, dissolved methane is also present and should be removed to prevent greenhouse gas emissions into the environment. Potentially, another recently discovered microbial pathway, n-damo (nitrite-dependent anaerobic methane oxidation) could be used for this purpose. In the present paper, we explore the feasibility of simultaneously removing methane and ammonium anaerobically, starting with granules from a full-scale anammox bioreactor. We describe the development of a co-culture of anammox and n-damo bacteria using a medium containing methane, ammonium and nitrite. The results are discussed in the context of other recent studies on the application of anaerobic methane- and ammonia-oxidizing bacteria for wastewater treatment.
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Simultaneous nitrite-dependent anaerobic methane and ammonium oxidation processes.
Appl. Environ. Microbiol.
PUBLISHED: 08-12-2011
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Nitrite-dependent anaerobic oxidation of methane (n-damo) and ammonium (anammox) are two recently discovered processes in the nitrogen cycle that are catalyzed by n-damo bacteria, including "Candidatus Methylomirabilis oxyfera," and anammox bacteria, respectively. The feasibility of coculturing anammox and n-damo bacteria is important for implementation in wastewater treatment systems that contain substantial amounts of both methane and ammonium. Here we tested this possible coexistence experimentally. To obtain such a coculture, ammonium was fed to a stable enrichment culture of n-damo bacteria that still contained some residual anammox bacteria. The ammonium supplied to the reactor was consumed rapidly and could be gradually increased from 1 to 20 mM/day. The enriched coculture was monitored by fluorescence in situ hybridization and 16S rRNA and pmoA gene clone libraries and activity measurements. After 161 days, a coculture with about equal amounts of n-damo and anammox bacteria was established that converted nitrite at a rate of 0.1 kg-N/m(3)/day (17.2 mmol day(-1)). This indicated that the application of such a coculture for nitrogen removal may be feasible in the near future.
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Antiagregation and anticoagulation, relationship with upper gastrointestinal bleeding.
Rev Esp Enferm Dig
PUBLISHED: 07-21-2011
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the high prevalence of cardiovascular diseases in the modern society brings a high prescription of platelet antiaggregation and anticoagulant medications. These treatments have been related to an increased incidence of upper gastrointestinal bleedings (UGB). Our aim was to estimate the fraction of UGB´s presented to our hospital that was related to this kind of treatments and describe their clinical features in our environment.
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The use of silver nylon in preventing surgical site infections following colon and rectal surgery.
Dis. Colon Rectum
PUBLISHED: 07-07-2011
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Patients who undergo colorectal surgery have up to a 30% chance of developing a surgical site infection postoperatively. Silverlon is a silver nylon dressing designed to prevent surgical site infections, but only anecdotal evidence has previously supported its efficacy.
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Safety of parecoxib in asthmatic patients with aspirin-exacerbated respiratory disease.
Int. Arch. Allergy Immunol.
PUBLISHED: 05-19-2011
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Aspirin-exacerbated respiratory disease (AERD) affects a subset of patients with asthma. Cyclooxygenase 2 inhibitors are a safe alternative in patients with AERD. Parecoxib is the first cyclooxygenase 2 selective drug for parenteral administration, especially useful after surgery thanks to its analgesic power. The aim of the study is to assess the tolerance of parecoxib (Dynastat; Pfizer) given by intramuscular route in patients with AERD.
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Macrophage migration inhibitory factor: a downregulator of early T cell-dependent IFN-gamma responses in Plasmodium chabaudi adami (556 KA)-infected mice.
J. Immunol.
PUBLISHED: 04-25-2011
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Neutralization of macrophage migration inhibitory factor (MIF) increases anti-tumor cytotoxic T cell responses in vivo and IFN-? responses in vitro, suggesting a plausible regulatory role for MIF in T cell activation. Considering that IFN-? production by CD4(+) T cells is pivotal to resolve murine malaria and that secretion of MIF is induced by Plasmodium chabaudi adami parasites, we investigated the effect of MIF deficiency on the infection with this pathogen. Infections with P. c. adami 556 KA parasites were more efficiently controlled in MIF-neutralized and MIF-deficient (knockout [KO]) BALB/c mice. The reduction in parasitemia was associated with reduced production of IL-4 by non-T/non-B cells throughout patent infection. At day 4 postinfection, higher numbers of activated CD4(+) cells were measured in MIF KO mice, which secreted more IFN-?, less IL-4, and less IL-10 than did CD4(+) T cells from wild-type mice. Enhanced IFN-? and decreased IL-4 responses also were measured in MIF KO CD4(+) T cells stimulated with or without IL-12 and anti-IL-4 blocking Ab to induce Th1 polarization. However, MIF KO CD4(+) T cells efficiently acquired a Th2 phenotype when stimulated in the presence of IL-4 and anti-IL-12 Ab, indicating normal responsiveness to IL-4/STAT6 signaling. These results suggest that by promoting IL-4 responses in cells other than T/B cells during early P. c. adami infection, MIF decreases IFN-? secretion in CD4(+) T cells and, additionally, has the intrinsic ability to render CD4(+) T cells less capable of acquiring a robust Th1 phenotype when stimulated in the presence of IL-12.
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[Analysis of cytomegalovirus infection and its consequences in renal transplantation: a decade analysis].
Med Clin (Barc)
PUBLISHED: 04-21-2011
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Cytomegalovirus (CMV) is one of the most important pathogens in renal transplant patients. It can cause infection and illness, as well as serious direct and indirect consequences.
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Influence of MRP2 on MPA pharmacokinetics in renal transplant recipients-results of the Pharmacogenomic Substudy within the Symphony Study.
Nephrol. Dial. Transplant.
PUBLISHED: 03-22-2011
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The aim of this study was to determine the relationship between single-nucleotide polymorphisms (SNPs) in MRP2 genes and mycophenolic acid (MPA) pharmacokinetics in renal transplant recipients of the Symphony Pharmacogenomic substudy.
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A non-invasive thermal drift compensation technique applied to a spin-valve magnetoresistive current sensor.
Sensors (Basel)
PUBLISHED: 01-10-2011
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A compensation method for the sensitivity drift of a magnetoresistive (MR) Wheatstone bridge current sensor is proposed. The technique was carried out by placing a ruthenium temperature sensor and the MR sensor to be compensated inside a generalized impedance converter circuit (GIC). No internal modification of the sensor bridge arms is required so that the circuit is capable of compensating practical industrial sensors. The method is based on the temperature modulation of the current supplied to the bridge, which improves previous solutions based on constant current compensation. Experimental results are shown using a microfabricated spin-valve MR current sensor. The temperature compensation has been solved in the interval from 0 °C to 70 °C measuring currents from -10 A to +10 A.
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ApoB-100, ApoE and CYP7A1 gene polymorphisms in Mexican patients with cholesterol gallstone disease.
World J. Gastroenterol.
PUBLISHED: 09-28-2010
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To determine the possible association of the ApoB-100 (XbaI), ApoE (HhaI) and CYP7A1 (BsaI) gene polymorphisms, with the development of cholesterol gallstone disease (GD) in a Mexican population.
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[Comparison between five growth curves used in a public hospital].
Rev. Invest. Clin.
PUBLISHED: 07-06-2010
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To compare five curves routinely used for growth evaluation in preterm newborns in a public hospital in Leon, Guanajuato, and to identify those with similar diagnosis according to the reference curve (Williams) in order to determine their usefulness in the clinical practice.
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Indoor orientation and mobility for learners who are blind.
Stud Health Technol Inform
PUBLISHED: 06-15-2010
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This study consisted of designing a mobile technology to identify the position and orientation of people who are blind in closed environments, such as a school, building or home, identifying the necessary infrastructure based on criteria of usability, reliability and accessibility, in order for PocketPC device interface developers to be able to define the technology to be used at an early stage. The technology consisted of using PocketPC devices with a data collecting application and another for the representation of space. We evaluated its usability, accessibility, reliability, efficiency, and availability. The results of the usability evaluation assured us that the interface designed and developed is usable for users who are blind, which is reaffirmed through the accessibility evaluation. The reliability, efficiency and availability evaluations of the system show that a user who is blind can use the system confidently, because it provides correct information for more independent navigation.
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Early statin use is an independent predictor of long-term graft survival.
NDT Plus
PUBLISHED: 03-29-2010
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Background. Statin use in renal transplantation has been associated with a lower risk of patient death but not with an improvement of graft functional survival. The aim of this study is to evaluate the effect of statin use in graft survival, death-censored graft survival and patient survival using the data recorded on the Spanish Late Allograft Dysfunction Study Group.Patients and methods. Patients receiving a renal allograft in Spain in 1990, 1994, 1998 and 2002 were considered. Since the mean follow-up in the 2002 cohort was 3 years, statin use was analysed considering its introduction during the first year or during the initial 2 years after transplantation. Univariate and multivariate Cox regression analyses with a propensity score for statin use were employed to analyse graft survival, death-censored graft survival and patient survival.Results. In the 4682 evaluated patients, the early statin use after transplantation significantly increased from 1990 to 2002 (12.7%, 27.9%, 47.7% and 53.0%, P < 0.001). Statin use during the first year was not associated with graft or patient survival. Statin use during the initial 2 years was associated with a lower risk of graft failure (relative risk [RR] = 0.741 and 95% confidence interval [CI] = 0.635-0.866, P < 0.001) and patient death (RR = 0.806 and 95% CI = 0.656-0.989, P = 0.039). Death-censored graft survival was not associated with statin use during the initial 2 years.Conclusion. The early introduction of statin treatment after transplantation is associated with a significant decrease in late graft failure due to a risk reduction in patient death.
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The IL-12p70/IL-10 interplay is differentially regulated by free heme and hemozoin in murine bone-marrow-derived macrophages.
Int. J. Parasitol.
PUBLISHED: 02-08-2010
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The outcome of malarial anemia is determined by a complex interplay between pro-inflammatory and anti-inflammatory cytokines, its severity associated with accumulation of hemozoin (Hz) in macrophages, elevated IL-10 responses and impaired IL-12 production. Although free heme contributes to malarial anemia by inducing oxidative damage of red blood cells (RBCs) and enhancing their clearance by phagocytes, its impact on IL-12/IL-10 interactions has not been fully characterized. Herein, the effect of hemin (HE) on IL-12 and IL-10 responses was studied in murine bone marrow-derived macrophages (BMDM) and compared with synthetic Hz. Our data reveal that HE induces modest inhibition of IL-12p70 responses to lipopolysaccharide (LPS) whereas Hz significantly impairs IL-12p70 responses to IFNgamma/LPS through down-regulation of IL-12p35 and p40 gene expression. Although reactive oxygen species (ROS) are generated after short-term exposure to HE and Hz, prolonged exposure to these iron protoporphyrins has opposite effects on the cellular redox status, HE being the only compound able to promote persistent ROS production. Accordingly, the inhibitory effect of HE on IL-12p70 seems sustained by redox-dependent induction of IL-10 and is partially controlled by the p38 mitogen-activated protein kinase (MAPK) signalling pathway. Indeed, treatment with n-acetylcysteine (NAC) or with the p38 MAPK inhibitor SB203580 inhibits IL-10 responses and significantly restores IL-12p70 responses to IFNgamma/LPS in HE-conditioned BMDM. Our results suggest that oxidant stress induced by free heme may potentially contribute to sustained production of IL-10 and down-regulation of IL-12 responses in malaria.
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The role of different hyaluronic acids in the articular cartilage of rabbit.
Open Orthop J
PUBLISHED: 01-19-2010
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To elucidate if the differences found in the physico-chemical and rheological behaviour of Hyaluronic Acids result in different in vivo activity. For this purpose two Hyaluronic Acids (HA), HA-1 and HA-2, with similar molecular weight but different percentage of concentration variation, were compared through an osteoarthritis model.
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Antimutagenicity mechanisms of the Rhoeo discolor ethanolic extract.
Exp. Toxicol. Pathol.
PUBLISHED: 01-03-2010
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Rhoeo discolor, a medical plant from Mexico, is known to be an antioxidant and chemoprotective antimutagen. Rhoeo discolor ethanolic extract (EERD) is a complex mixture, so in this study its antimutagenic mechanisms were further evaluated.
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Concept mapping for virtual rehabilitation and training of the blind.
IEEE Trans Neural Syst Rehabil Eng
PUBLISHED: 09-22-2009
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Concept mapping is a technique that allows for the strengthening of the learning process, based on graphic representations of the learners mental schemes. However, due to its graphic nature, it cannot be utilized by learners with visual disabilities. In response to this limitation we implemented a study that involves the design of AudiodMC, an audio-based, virtual environment for concept mapping designed for use by blind users and aimed at virtual training and rehabilitation. We analyzed the stages involved in the design of AudiodMC from a user-centered design perspective, considering user involvement and usability testing. These include an observation stage to learn how blind learners construct conceptual maps using concrete materials, a design stage to design of a software tool that aids blind users in creating concept maps, and a cognitive evaluation stage using AudiodMC. We also present the results of a study implemented in order to determine the impact of the use of this software on the development of essential skills for concept mapping (association, classification, categorization, sorting and summarizing). The results point to a high level of user acceptance, having identified key sound characteristics that help blind learners to learn concept codification and selection skills. The use of AudiodMC also allowed for the effective development of the skills under review in our research, thus facilitating meaningful learning.
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Fecal diversion in perirectal fistulizing Crohns disease is an underutilized and potentially temporary means of successful treatment.
Am Surg
PUBLISHED: 09-04-2009
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The purpose of this study was to determine the outcome of patients treated with fecal diversion for perirectal fistulizing Crohns disease. Thirty-nine patients were identified and followed for an average of 60 months. Patients were divided into two groups based on surgical treatment: local surgical treatment only and fecal diversion in addition to local surgical therapy. Thirteen patients (33%) underwent fecal diversion due to the severity of their disease. Eleven of these patients (85%) had complete resolution of their fistulas and only two (15%) required proctectomy. In contrast, only five out of 26 patients (19%) who underwent local surgical procedures alone had complete perirectal disease resolution. Intestinal continuity was restored in six patients (46%) and three of these patients (50%) remained disease free. The remaining three patients had disease recurrence, which required additional local procedures in one patient (17%), but with eventual resolution; the other two patients (33%) necessitated rediversion. Our data suggest that fecal diversion is a viable treatment option for severe perirectal fistulizing Crohns disease and may be associated with a higher rate of resolution than local surgical treatment alone. In addition, we demonstrate a higher rate of successful intestinal continuity restoration than is typically reported.
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[Changes in bone and mineral metabolism in kidney transplant patients with chronic kidney disease].
Nefrologia
PUBLISHED: 08-14-2009
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Recently, the Foundation has proposed new definitions KDIGO to refer to the alterations of bone - mineral metabolism in patients with chronic renal disease (CRD), relegating the traditional term of renal osteodystrophy (ODR). RECOMMEND: The term ODR exclusively to define alterations in bone morphology and architecture characteristic of the ERC. - And the term of bone-mineral alteration associated with the CRD to describe biochemical changes, and skeletal calcifications that occur as a result of alterations in mineral metabolism in the CRD.
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[Progression factors in chronic kidney disease. Non-immunological mechanisms].
Nefrologia
PUBLISHED: 08-14-2009
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Non-immunological factors in the progression of kidney disease in transplant patients are the following: high blood pressure, proteinuria, dislypidemia, etc. 1. Arterial hypertension treatment: Blood pressure must be measured periodically in all transplant patients. Similarly to native kidneys, in renal transplant patients arterial hypertension is a risk factor in the progression of kidney disease. Arterial hypertension represent a clinical marker of chronic allograft nephropathy and contributes to graft loss and to the morbid- mortality of these patients (Evidence level C). Blood pressure control should be < 130/80 mm Hg for renal transplant patients without proteinuria and 125/75 mm Hg for proteinuric patients (> 1 g/24 hours). Hypertension and proteinuria are frequently associated in the same patients, a global treatment of both seems more rational (Evidence level C). General measures should be instigated first with pharmacological therapy. All antihypertensive drugs are useful in renal transplant patients and the majority of patients will need two or more drugs. In proteinuric patients an angiotensin receptor antagonist or an ACE-inhibitor should be initiated. It is advisable to monitor the serum potassium and creatinine after the start of this drugs or during the treatment periodically, especially in patients with chronic kidney disease stage IV-V. 2. Proteinuria treatment: Proteinuria has been strongly correlated with reduced function and graft survival. Lowering proteinuria to values as near to normal as possible (< 0.5 g/24 hours). To reduce proteinuria, an angiotensin receptor antagonist, an ACE-inhibitor or a combination of both are required, with serum potassium or creatinine monitoring, especially in patients with chronic kidney disease stage IV-V. 3. Dyslipidemia treatment: For kidney transplant recipients the assessment of dyslipidemias should include a complete fasting lipid profile with total cholesterol, LDL, HDL, and triglycerides. Evidence from the general population indicates that treatment of dyslipidemias reduces cardiovascular disease and evidence in kidney transplant patients suggests that judicious treatment can be safe and effective in improving dyslipidemia. Therapeutic goal must be LDL < 100 mg/dl. (Evidence level C). 4. Others: Cigarette smoking, glucose intolerance or diabetes control and obesity should be assessed.
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Laparoscopic-assisted transvaginal approach for sigmoidectomy and rectocolpopexy.
JSLS
PUBLISHED: 08-08-2009
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Laparoscopic-assisted colonic resection has been well described for multiple surgical indications. This typically requires an abdominal incision for specimen removal that is associated with the majority of postoperative pain. We describe the first laparoscopic-assisted transvaginal approach for sigmoidectomy and rectocolpopexy for the treatment of rectal prolapse.
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Mobile serious games for collaborative problem solving.
Stud Health Technol Inform
PUBLISHED: 07-14-2009
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This paper presents the results obtained from the implementation of a series of learning activities based on mobile serious games (MSG) for the development of problem-solving and collaborative skills in Chilean 8th grade students. Three MSGs were developed and played by teams of four students, who had to solve the problems posed by the game collaboratively. The data shows that the experimental group had a higher perception of their own skills of collaboration and of the plan execution dimension of problem solving than the control group, providing empirical evidence regarding the contribution of MSGs to the development of collaborative problem-solving skills.
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Cloning and constitutive expression of Deschampsia antarctica Cu/Zn superoxide dismutase in Pichia pastoris.
BMC Res Notes
PUBLISHED: 05-11-2009
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Deschampsia antarctica shows tolerance to extreme environmental factors such as low temperature, high light intensity and an increasing UV radiation as result of the Antarctic ozone layer thinning. It is very likely that the survival of this species is due to the expression of genes that enable it to tolerate high levels of oxidative stress. On that account, we planned to clone the D. antarctica Cu/ZnSOD gene into Pichia pastoris and to characterize the heterologous protein.
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Molecular characterization of a cDNA encoding Cu/Zn superoxide dismutase from Deschampsia antarctica and its expression regulated by cold and UV stresses.
BMC Res Notes
PUBLISHED: 05-11-2009
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The Copper/Zinc superoxide dismutase (Cu/ZnSOD) gene, SOD gene, was isolated from a Deschampsia antarctica Desv. by cDNA library screening. The expression of SOD gene in the leaves of D. antarctica was determined by RT-PCR and its differential expression of gene transcripts in conditions of cold and UV radiation stresses was revealed by northern blot.
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A randomized trial of basiliximab with three different patterns of cyclosporin A initiation in renal transplant from expanded criteria donors and at high risk of delayed graft function.
Clin Transplant
PUBLISHED: 05-01-2009
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This study assays therapy with basiliximab and different patterns of cyclosporin A (CsA) initiation in renal transplant (RT) recipients from expanded criteria donors (ECD) and at high risk of delayed graft function (DGF). A multicentre six-month open-label randomized trial with three parallel groups treated with basiliximab plus steroids, mycophenolate mofetil and different patterns of CsA initiation: early within 24 h post-RT at 3 mg/kg/d (Group 1; n = 38), and at 5 mg/kg/d (Group 2; n = 40), or delayed after 7-10 d at 5 mg/kg/d (Group 3; n = 36). There were no differences among groups in six months GFR (43.1 +/- 12, 48.0 +/- 14 and 47.2 +/- 17 mL/min, respectively), DGF (Group 1: 31%, Group 2: 37%, Group 3: 42%), nor biopsy-proven acute rejection, although clinically treated and biopsy-proven acute rejection was significantly higher in Group 3 (25%) vs. Group 1 (5.3%, p < 0.05). At six months no differences were observed in death-censored graft survival or patient survival. Induction therapy with basiliximab and three CsA-ME initiation patterns in RT recipients from ECD and at high risk of DGF presented good renal function and graft survival at six months. Late onset group did not achieve improvement in DGF rate and showed a higher incidence of clinically treated and biopsy-proven acute rejection.
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Health-related quality of life of patients receiving low-toxicity immunosuppressive regimens: a substudy of the Symphony Study.
Transplantation
PUBLISHED: 04-23-2009
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To evaluate health-related quality of life (HRQoL) in patients with different low-toxicity regimens posttransplantation.
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The pharmacokinetics of mycophenolate mofetil in renal transplant recipients receiving standard-dose or low-dose cyclosporine, low-dose tacrolimus or low-dose sirolimus: the Symphony pharmacokinetic substudy.
Nephrol. Dial. Transplant.
PUBLISHED: 04-08-2009
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Exposure to mycophenolic acid (MPA), the primary active metabolite of mycophenolate mofetil (MMF), is correlated with therapeutic efficacy of MMF but varies depending on the concomitantly administered immunosuppressive drugs.
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Breastfeeding and metabolic indicators in Mexican premature newborns.
Rev. Invest. Clin.
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Morbidity and mortality rates are higher among preterm infants due to physiological immaturity and greater growth demands. Nutritional intervention contributes to proper weight gain, which translates into better growth and neurological development, and prevents the onset of metabolic complications. The effect of breastfeeding duration was studied in the analytic profile at the end of the first six months of life.
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Medicinal plants in the southern region of the State of Nuevo León, México.
J Ethnobiol Ethnomed
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Although the flora of the State of Nuevo León is well known, there are few records of ethnobotancial information. An ethnobotanical study was undertaken in order to know the medicinal plants used by people living at the scrublands and oak-pine forest areas in the southern Nuevo León. Collection of plants specimens and interviews were carried out among the people of the municipalities of Aramberri, Galeana, and Zaragoza. Since former studies in the region are scarce, the aim of this work was to record the medicinal species and their uses in the scrublands and oak-pine forest areas, of southern Nuevo León, Mexico, and also to know if there are differences in the number of species and number of uses knowledge by people.
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Do drug transporter (ABCB1) SNPs and P-glycoprotein function influence cyclosporine and macrolides exposure in renal transplant patients? Results of the pharmacogenomic substudy within the symphony study.
Transpl. Int.
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The function of the efflux pump P-glycoprotein (Pgp) and ABCB1 single nucleotide polymorphisms (SNPs) should be considered as important tools to deepen knowledge of drug nephrotoxicity and disposition mechanisms. The aim of this study is to investigate the association of C3435T, G2677T, C1236T, and T129C ABCB1 SNPs with Pgp activity and exposure to different immunosuppressive drugs in renal transplant patients. Patients included in the Symphony Pharmacogenomic substudy were genotyped for ABCB1 SNPs. According to the design, patients were randomized into four immunosuppressive regimens: low and standard dose of cyclosporine (n = 30), tacrolimus (n = 13), and sirolimus (n = 23) concomitantly with mycophenolate and steroids. Pgp activity was evaluated in PBMC using the Rhodamine 123 efflux assay. TT carrier patients on C3435T, G2677T, and C1236T SNPs (Pgp-low pumpers) showed lower Pgp activity than noncarriers. Pgp-high pumpers treated with cyclosporine showed lower values of Pgp function than macrolides. There was a negative correlation between cyclosporine AUC and Pgp activity at 3 months. Results did not show any correlation between tacrolimus and sirolimus AUC and Pgp activity at 3 months. We found an important role of the ABCB1 SNPs Pgp function in CD3(+) peripheral blood lymphocytes from renal transplant recipients. Pgp activity was influenced by cyclosporine but not macrolides exposure.
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Antimutagenic evaluation of vitamins B1, B6 and B12 in vitro and in vivo, with the Ames test.
Food Chem. Toxicol.
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The aim of this work is to evaluate vitamins B antimutagenic effect against alkylatings methyl-N-nitro-N-nitrosoguanidine (MNNG), ethyl-N-nitro-N- nitrosoguanidine (ENNG), frameshift mutagens 2-aminoanthracene (2AA) and 2-acetyl-amino-fluorene (2AF) and ROS-generating antibiotics norfloxacin (NOR) and nalidixic acid (NLX), using the in vitro Ames test. In vivo antimutagenesis studies were performed against urinary mutagens induced by NOR (70 mg/kg) or NLX (100 mg/kg) in CD1 mice. Vitamin B1 was antimutagenic against alkylatings MNNG (P<0.05) or ENNG (P<0.001). In fact as per the results observed during the current study, none of the vitamins reduced mutagenesis caused by frameshift mutagens. All of them reduced mutagenesis of NOR or NLX (P<0.001). In vivo studies showed that vitamins B1 and B6 (10 or 100 mg/kg) reduced urinary mutagens from NOR (P<0.001) or NLX (P<0.02) either free or ?-glucoronidase-conjugates. None of the studied samples were toxic for the employed antimutagenic system. Vitamin B12 (4 mg/kg) reduced urinary mutagens of NOR or NLX (P<0.02). Vitamins B inhibited DNA mutations induced by ROS generated by NLX or NOR, both in vitro and in vivo. Vitamin B1is antimutagenic against mutations induced by the alkylating MNNG or ENNG. Based on the observations, employment of vitamins B in vivo can be a promising alternative to reduce genotoxic risk exposure to ROS.
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Increased hospital stay and allograft dysfunction in renal transplant recipients with Cyp2c19 AA variant in SNP rs4244285.
Drug Metab. Dispos.
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Pharmacogenetics correlates certain genetic variants, such as single nucleotide polymorphisms (SNPs), with blood drug levels, efficacy, and adverse effects of the treatment. Tacrolimus is mainly metabolized via CYP3A4/5, whereas CYP2C19 and CYP3A4/5 are responsible for omeprazole metabolism. Omeprazole inhibits tacrolimus metabolism via CYP3A5 in patients carrying variant alleles of CYP2C19, increasing tacrolimus blood concentrations. Seventy-five renal transplant recipients treated with tacrolimus and concomitant omeprazole were genotyped in a panel of 37 SNPs with use of Sequenom MassArray. The patients with CYP2C19*2/*2 genotype (n = 4) showed a median posttransplantation hospital stay of 27.5 days (95% confidence interval [CI], 23-39 days), compared with 12 days (95% CI, 10-15 days) in patients with CYP2C19*1/*1 or CYP2C19*1/*2 (n = 71; P = 0.016, Kruskal-Wallis test).The difference in hospital stay was directly correlated with an increase in tacrolimus levels (C(min)/[dose/weight]) during the first week after trasplantation (in 59 patients with data on levels; P = 0.021, Kruskal-Wallis), excluding the patients with atypical metabolisms due to CYP3A5*1/*3 or CYP3A5*1/*1 genotype. Recipients with CYP2C19*2/*2 genotype also showed allograft delayed function (acute tubular necrosis in 3 patients). Genotyping of CYP3A5 and CYP2C19 in renal transplantation should be considered to be of interest when treating with tacrolimus and omeprazole, because CYP2C19*2/*2 variant indirectly elicits an increase of tacrolimus blood levels and, in our study population, the adverse effects described.
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In-frame mutations in exon 1 of SKI cause dominant Shprintzen-Goldberg syndrome.
Am. J. Hum. Genet.
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Shprintzen-Goldberg syndrome (SGS) is characterized by severe marfanoid habitus, intellectual disability, camptodactyly, typical facial dysmorphism, and craniosynostosis. Using family-based exome sequencing, we identified a dominantly inherited heterozygous in-frame deletion in exon 1 of SKI. Direct sequencing of SKI further identified one overlapping heterozygous in-frame deletion and ten heterozygous missense mutations affecting recurrent residues in 18 of the 19 individuals screened for SGS; these individuals included one family affected by somatic mosaicism. All mutations were located in a restricted area of exon 1, within the R-SMAD binding domain of SKI. No mutation was found in a cohort of 11 individuals with other marfanoid-craniosynostosis phenotypes. The interaction between SKI and Smad2/3 and Smad 4 regulates TGF-? signaling, and the pattern of anomalies in Ski-deficient mice corresponds to the clinical manifestations of SGS. These findings define SGS as a member of the family of diseases associated with the TGF-?-signaling pathway.
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Expression of macrophage migration inhibitory factor by osteoblastic cells: protection against cadmium toxicity.
Toxicol. Lett.
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Exposition to cadmium (Cd) has been linked to bone metabolism alterations and occurrence of osteoporosis. Despite its known renal toxicity which indirectly disrupts bone metabolism through impairment of vitamin D synthesis, increasing evidence argues for the direct action of Cd on bone-forming osteoblasts. Indeed, accumulation of Cd in osteoblasts and metal-induced cell death has been documented but little is known about the intracellular mechanisms of protection against this stress. In this work, we investigated the protection afforded by thiol-containing proteins against Cd cytotoxicity in MC3T3 osteoblastic cells. Viability of MC3T3 cells was reduced by Cd in a concentration-dependent manner with a LC(50) of 7.6±1.1?M. Depletion of glutathione by l-buthionine sulphoximine (BSO) increased cell sensitivity to Cd cytotoxicity, suggesting the involvement of thiol-containing peptides as a mechanism of protection. Accordingly, Cd was shown to promote progressive depletion of reduced thiol content and to stimulate the production of reactive oxygen species (ROS). Interestingly, low non cytotoxic concentrations of Cd increased the gene expression of macrophage migration inhibitory factor (MIF), also a thiol-containing protein. Inhibition of the transcription factor NF?B prevented Cd-dependent upregulation of MIF expression and consequently, increased Cd cytotoxicity in osteoblasts. Moreover, MIF deficient mouse osteoblasts were more sensitive to Cd cytotoxicity than the corresponding control cells. By gel-filtration chromatography, we demonstrated that MIF acts as a thiol-containing protein and thereby promotes Cd complexation. In accordance with its binding ability, addition of recombinant MIF to the culture medium reduced Cd cytotoxicity. Overall, upregulation of MIF expression by Cd may protect against the cytotoxicity of this metal in the osteoblasts.
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Alterations in bone and erythropoiesis in hemolytic anemia: comparative study in bled, phenylhydrazine-treated and Plasmodium-infected mice.
PLoS ONE
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Sustained erythropoiesis and concurrent bone marrow hyperplasia are proposed to be responsible for low bone mass density (BMD) in chronic hemolytic pathologies. As impaired erythropoiesis is also frequent in these conditions, we hypothesized that free heme may alter marrow and bone physiology in these disorders. Bone status and bone marrow erythropoiesis were studied in mice with hemolytic anemia (HA) induced by phenylhydrazine (PHZ) or Plasmodium infection and in bled mice. All treatments resulted in lower hemoglobin concentrations, enhanced erythropoiesis in the spleen and reticulocytosis. The anemia was severe in mice with acute hemolysis, which also had elevated levels of free heme and ROS. No major changes in cellularity and erythroid cell numbers occurred in the bone marrow of bled mice, which generated higher numbers of erythroid blast forming units (BFU-E) in response to erythropoietin. In contrast, low numbers of bone marrow erythroid precursors and BFU-E and low concentrations of bone remodelling markers were measured in mice with HA, which also had blunted osteoclastogenesis, in opposition to its enhancement in bled mice. The alterations in bone metabolism were accompanied by reduced trabecular bone volume, enhanced trabecular spacing and lower trabecular numbers in mice with HA. Taken together our data suggests that hemolysis exerts distinct effects to bleeding in the marrow and bone and may contribute to osteoporosis through a mechanism independent of the erythropoietic stress.
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Teaching the blind to find their way by playing video games.
PLoS ONE
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Computer based video games are receiving great interest as a means to learn and acquire new skills. As a novel approach to teaching navigation skills in the blind, we have developed Audio-based Environment Simulator (AbES); a virtual reality environment set within the context of a video game metaphor. Despite the fact that participants were naïve to the overall purpose of the software, we found that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building using audio based cues alone. This was confirmed by a series of behavioral performance tests designed to assess the transfer of acquired spatial information to a large-scale, real-world indoor navigation task. Furthermore, learning the spatial layout through a goal directed gaming strategy allowed for the mental manipulation of spatial information as evidenced by enhanced navigation performance when compared to an explicit route learning strategy. We conclude that the immersive and highly interactive nature of the software greatly engages the blind user to actively explore the virtual environment. This in turn generates an accurate sense of a large-scale three-dimensional space and facilitates the learning and transfer of navigation skills to the physical world.
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Individualised vs fixed dose of oral 17?-oestradiol for induction of puberty in girls with Turner syndrome: an open-randomised parallel trial.
Eur. J. Endocrinol.
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Oestrogen induction of pubertal changes in Turner girls may reinforce their psychological well-being and may also optimise final height; however, oestrogen type, dose, and route are not well established.
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Late evolution of kidney transplants in elderly donors and recipients receiving initial immunosuppressant treatment with daclizumab, mycophenolate mofetil, and delayed introduction of tacrolimus.
Nefrologia
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Organ transplants in elderly recipients have increased over the past few years. This situation poses specific problems both in terms of organs and recipients; therefore, immunosuppressant regimens must be adapted accordingly. A previous study demonstrated good initial results in kidney transplant cases in which older donors and recipients (average ages of 64.4 years and 61.3 years) had received initial immunosuppressant therapy with daclizumab and mycophenolate mofetil as well as delayed introduction of reduced-dose tacrolimus. In this study we reviewed the long-term results in the same group of patients.
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Alterations in RAS-MAPK genes in 200 Spanish patients with Noonan and other neuro-cardio-facio-cutaneous syndromes. Genotype and cardiopathy.
Rev Esp Cardiol (Engl Ed)
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Molecular characterization of congenital heart diseases now includes the not infrequent dysmorphic Noonan syndrome. A study of 6 genes of the RAS-MAPK pathway in Spanish patients is presented: the impact of heart disease, clinical expressivity, and diagnostic yield are investigated.
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Further insight into the photostability of the pyrene fluorophore in halogenated solvents.
Chemphyschem
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Pyrene fluorophores of pyrene-functionalized CdSe quantum dots (QD@Py), as well as alkylpyrene and pyrene itself (Py), undergo fast degradation in aerated chloroform under ultraviolet-A (UV-A, 316
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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.