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Find video protocols related to scientific articles indexed in Pubmed.
Seeking potential anticonvulsant agents that target GABAA receptors using experimental and theoretical procedures.
J. Comput. Aided Mol. Des.
PUBLISHED: 07-01-2014
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The aim of this study was to identify compounds that possess anticonvulsant activity by using a pentylenetetrazol (PTZ)-induced seizure model. Theoretical studies of a set of ligands, explored the binding affinities of the ligands for the GABAA receptor (GABAAR), including some benzodiazepines. The ligands satisfy the Lipinski rules and contain a pharmacophore core that has been previously reported to be a GABAAR activator. To select the ligands with the best physicochemical properties, all of the compounds were analyzed by quantum mechanics and the energies of the highest occupied molecular orbital and lowest unoccupied molecular orbital were determined. Docking calculations between the ligands and the GABAAR were used to identify the complexes with the highest Gibbs binding energies. The identified compound D1 (dibenzo(b,f)(1,4)diazocine-6,11(5H,12H)-dione) was synthesized, experimentally tested, and the GABAAR-D1 complex was submitted to 12-ns-long molecular dynamics (MD) simulations to corroborate the binding conformation obtained by docking techniques. MD simulations were also used to analyze the decomposition of the Gibbs binding energy of the residues involved in the stabilization of the complex. To validate our theoretical results, molecular docking and MD simulations were also performed for three reference compounds that are currently in commercial use: clonazepam (CLZ), zolpidem and eszopiclone. The theoretical results show that the GABAAR-D1, and GABAAR-CLZ complexes bind to the benzodiazepine binding site, share a similar map of binding residues, and have similar Gibbs binding energies and entropic components. Experimental studies using a PTZ-induced seizure model showed that D1 possesses similar activity to CLZ, which corroborates the predicted binding free energy identified by theoretical calculations.
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Early contamination of European flounder (Platichthys flesus) by PCDD/Fs and dioxin-like PCBs in European waters.
Mar. Pollut. Bull.
PUBLISHED: 05-19-2014
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Contamination levels and profiles of 7 polychlorinated-p-dioxins, 10 polychlorinated furans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were investigated in juvenile European flounder (Platichthys flesus) captured in different nursery areas in the northeastern Atlantic coast across its geographical distribution range. The toxic equivalent concentrations (WHO-TEQfish) were also determined in order to evaluate which P. flesus population was more exposed to dioxin-like toxicity. Juveniles caught in the Sørfjord (Norway) showed the lowest WHO-TEQfish concentration (0.052 pg WHO-TEQfish g(-1)wet weight) whereas the highest value was observed in fish from the Wadden Sea (The Netherlands; 0.291 pg WHO-TEQfish g(-1)ww), mainly due to the greater contribution of 2,3,7,8-tetrachlorodibenzo-p-dioxin, the most toxic congener. Nonetheless, when comparing the results with existent tissue residue-based toxicity benchmarks, no adverse effects resulting from PCDD/Fs and dl-PCBs are expected to occur in flounder from the studied systems.
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The activation of representative emotional verbal contexts interacts with vertical spatial axis.
Cogn Process
PUBLISHED: 05-13-2014
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Several experimental studies have shown that there exists an association between emotion words and the vertical spatial axis. However, the specific conditions under which this conceptual-physical interaction emerges are still unknown, and no study has been devised to test whether longer linguistic units than words can lead to a mapping of emotions on vertical space. In Experiment 1, Spanish and Colombian participants performed a representative verbal emotional contexts production task (RVEC task) requiring participants to produce RVEC for the emotions of joy, sadness, surprise, anger, fear, and disgust. The results showed gender and cultural differences regarding the average number of RVEC produced. The most representative contexts of joy and sadness obtained in Experiment 1 were used in Experiment 2 in a novel spatial-emotional congruency verification task (SECV task). After reading a sentence, the participants had to judge whether a probe word, displayed in either a high or low position on the screen, was congruent or incongruent with the previous sentence. The question was whether the emotion induced by the sentence could modulate the responses to the probes as a function of their position in a vertical axis by means of a metaphorical conceptual-spatial association. Overall, the results indicate that a mapping of emotions on vertical space can occur for linguistic units larger than words, but only when the task demands an explicit affective evaluation of the target.
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Multi-residue and multi-class determination of antibiotics in gilthead sea bream (Sparus aurata) by ultra high-performance liquid chromatography-tandem mass spectrometry.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 04-07-2014
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This paper describes a method for the determination of 41 antibiotics from seven different classes in gilthead sea bream (Sparus aurata) by ultra-high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol were simultaneously determined. Fourteen procedures for sample treatment were tested and an extraction with acetonitrile and ethylenediaminetetra acetic acid was found to be the best option. The methodology was validated in accordance with Decision 2002/657/EC. Precision in terms of relative standard deviation (RSD) was under 17% for all compounds, and the recoveries ranged from 92% to 111%. CC? and CC? were determined according to the maximum residue limit or the minimum required performance limit, when necessary. The validation provided evidence that the method was suitable for application in routine analysis for the detection and confirmation of antibiotics in muscle of gilthead sea bream, an important and intensively produced fish in aquaculture.
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Occurrence of PCDD/Fs and dioxin-like PCBs in superficial sediment of Portuguese estuaries.
Environ Sci Pollut Res Int
PUBLISHED: 04-04-2014
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Superficial sediments collected from seven estuarine systems located along the Portuguese coast were analyzed for 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs). Total PCDD/F concentration ranged from 4.6 to 464 pg g(-1) dry weight (dw), while that of dl-PCBs varied from 26.6 to 8,693 pg g(-1) dw. In general, the highest PCDD/F and dl-PCB concentrations were associated with densely populated and industrially impacted areas. Additionally, PCDD/F revealed a predominance of octachlorodibenzodioxin (OCDD) to total PCDD/Fs, while PCB 118 was the major contributor to total dl-PCBs. This study provided a global perspective of the contamination status of Portuguese estuaries by dioxin-like compounds and allowed a comparison between the investigated systems and other systems worldwide. PCDD/F and dl-PCB levels found in the collected sediments were lower than those of highly impacted areas from different parts of the globe. Nevertheless, comparison with guidelines and quality standards from other countries indicated that some Portuguese estuarine areas with a high industrialization level present PCDD/F and dl-PCB concentrations in superficial sediment that may constitute a risk to aquatic organisms.
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Nodulin 22, a novel small heat-shock protein of the endoplasmic reticulum, is linked to the unfolded protein response in common bean.
Mol. Plant Microbe Interact.
PUBLISHED: 04-04-2014
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The importance of plant small heat shock proteins (sHsp) in multiple cellular processes has been evidenced by their unusual abundance and diversity; however, little is known about their biological role. Here, we characterized the in vitro chaperone activity and subcellular localization of nodulin 22 of Phaseolus vulgaris (PvNod22; common bean) and explored its cellular function through a virus-induced gene silencing-based reverse genetics approach. We established that PvNod22 facilitated the refolding of a model substrate in vitro, suggesting that it acts as a molecular chaperone in the cell. Through microscopy analyses of PvNod22, we determined its localization in the endoplasmic reticulum (ER). Furthermore, we found that silencing of PvNod22 resulted in necrotic lesions in the aerial organs of P. vulgaris plants cultivated under optimal conditions and that downregulation of PvNod22 activated the ER-unfolded protein response (UPR) and cell death. We also established that PvNod22 expression in wild-type bean plants was modulated by abiotic stress but not by chemicals that trigger the UPR, indicating PvNod22 is not under UPR control. Our results suggest that the ability of PvNod22 to suppress protein aggregation contributes to the maintenance of ER homeostasis, thus preventing the induction of cell death via UPR in response to oxidative stress during plant-microbe interactions.
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Effect of the replacement of Tifton 85 with maniçoba hay on the performance of Morada Nova hair sheep.
Trop Anim Health Prod
PUBLISHED: 04-01-2014
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The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36?±?1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81% WB) was higher (P??0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm(2)) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics.
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Validation of the Killip-Kimball classification and late mortality after acute myocardial infarction.
Arq. Bras. Cardiol.
PUBLISHED: 03-19-2014
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The classification or index of heart failure severity in patients with acute myocardial infarction (AMI) was proposed by Killip and Kimball aiming at assessing the risk of in-hospital death and the potential benefit of specific management of care provided in Coronary Care Units (CCU) during the decade of 60.
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[Incidence of haematological neoplasms in Castilla y Leon.]
Med Clin (Barc)
PUBLISHED: 03-06-2014
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We aimed to assess the incidence of haematological neoplasms (HNs) in Castilla y León (2,5 million inhabitants) and its distribution by age, gender and histological type.
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Trends in the use of natural antioxidants in active food packaging: a review.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 03-04-2014
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The demand for natural antioxidant active packaging is increasing due to its unquestionable advantages compared with the addition of antioxidants directly to the food. Therefore, the search for antioxidants perceived as natural, namely those that naturally occur in herbs and spices, is a field attracting great interest. In line with this, in the last few years, natural antioxidants such as ?-tocopherol, caffeic acid, catechin, quercetin, carvacrol and plant extracts (e.g. rosemary extract) have been incorporated into food packaging. On the other hand, consumers and the food industry are also interested in active biodegradable/compostable packaging and edible films to reduce environmental impact, minimise food loss and minimise contaminants from industrial production and reutilisation by-products. The present review focuses on the natural antioxidants already applied in active food packaging, and it reviews the methods used to determine the oxidation protection effect of antioxidant active films and the methods used to quantify natural antioxidants in food matrices or food simulants. Lastly consumers' demands and industry trends are also addressed.
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Multivariate time-dependent comparison of the impact of lenalidomide in lower-risk myelodysplastic syndromes with chromosome 5q deletion.
Br. J. Haematol.
PUBLISHED: 02-24-2014
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The impact of lenalidomide treatment on long-term outcomes of patients with lower risk myelodysplastic syndromes (MDS) and chromosome 5q deletion (del(5q)) is unclear. This study used time-dependent multivariate methodology to analyse the influence of lenalidomide therapy on overall survival (OS) and acute myeloblastic leukaemia (AML) progression in 215 patients with International Prognostic Scoring System (IPSS) low or intermediate-1 risk and del(5q). There were significant differences in several relevant characteristics at presentation between patients receiving (n = 86) or not receiving lenalidomide (n = 129). The 5-year time-dependent probabilities of OS and progression to AML were 62% and 31% for patients receiving lenalidomide and 42% and 25% for patients not receiving lenalidomide; differences were not statistically significant in multivariate analysis that included all variables independently associated with those outcomes (OS, P = 0·45; risk of AML, P = 0·31, respectively). Achievement of RBC transfusion independency (P = 0·069) or cytogenetic response (P = 0·021) after lenalidomide was associated with longer OS in multivariate analysis. These data clearly show that response to lenalidomide results in a substantial clinical benefit in lower risk MDS patients with del(5q). Lenalidomide treatment does not appear to increase AML risk in this population of patients.
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Foundations for modeling the dynamics of gene regulatory networks: a multilevel-perspective review.
J Bioinform Comput Biol
PUBLISHED: 01-29-2014
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A promising alternative for unraveling the principles under which the dynamic interactions among genes lead to cellular phenotypes relies on mathematical and computational models at different levels of abstraction, from the molecular level of protein-DNA interactions to the system level of functional relationships among genes. This review article presents, under a bottom-up perspective, a hierarchy of approaches to modeling gene regulatory network dynamics, from microscopic descriptions at the single-molecule level in the spatial context of an individual cell to macroscopic models providing phenomenological descriptions at the population-average level. The reviewed modeling approaches include Molecular Dynamics, Particle-Based Brownian Dynamics, the Master Equation approach, Ordinary Differential Equations, and the Boolean logic abstraction. Each of these frameworks is motivated by a particular biological context and the nature of the insight being pursued. The setting of gene network dynamic models from such frameworks involves assumptions and mathematical artifacts often ignored by the non-specialist. This article aims at providing an entry point for biologists new to the field and computer scientists not acquainted with some recent biophysically-inspired models of gene regulation. The connections promoting intuition between different abstraction levels and the role that approximations play in the modeling process are highlighted throughout the paper.
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Effectiveness and safety of different azacitidine dosage regimens in patients with myelodysplastic syndromes or acute myeloid leukemia.
Leuk. Res.
PUBLISHED: 01-24-2014
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We investigated the effectiveness and tolerability of azacitidine in patients with World Health Organization-defined myelodysplastic syndromes, or acute myeloid leukemia with 20-30% bone marrow blasts. Patients were treated with azacitidine, with one of three dosage regimens: for 5 days (AZA 5); 7 days including a 2-day break (AZA 5-2-2); or 7 days (AZA 7); all 28-day cycles. Overall response rates were 39.4%, 67.9%, and 51.3%, respectively, and median overall survival (OS) durations were 13.2, 19.1, and 14.9 months. Neutropenia was the most common grade 3-4 adverse event. These results suggest better effectiveness-tolerability profiles for 7-day schedules.
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Synergistic antinociceptive effect and gastric safety of the combination of docosahexaenoic acid and indomethacin in rats.
Pharmacol. Biochem. Behav.
PUBLISHED: 01-21-2014
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The use of analgesics is limited by the presence of significant adverse side effects. Thus, combinations of non-steroidal anti-inflammatory drugs (NSAIDs) with other antinociceptive agents are frequently used to decrease these adverse reactions. The aims of this work were to evaluate the antinociceptive interaction of the systemic administration of the combination of DHA and indomethacin through an isobolographic analysis of the theoretical and experimental antinociceptive effect and to demonstrate the gastric safety of the mixture compared with indomethacin alone. Female Wistar rats were orally administered indomethacin (1-10 mg/kg), DHA (100-300 mg/kg), or the DHA-indomethacin mixture at a fixed-ratio combination (1:1, 1:3, 3:1), and the antinociceptive effects of these treatments were evaluated through the formalin (1%) test. An isobolographic analysis was performed to characterize the antinociceptive interaction between DHA and indomethacin. The degree of gastric injury in all of the rats was determined 1 h after the formalin test. The theoretical ED?? values (Zadd) for the 1:1, 1:3, and 3:1 combinations were 73.48 ± 8.96, 37.75 ± 4.50, and 109.2 ± 13.43 mg/kg, p.o., respectively, and the experimental ED30 values (Zexp) were 43.63 ± 5.18, 13.13 ± 1.61, and 54.20 ± 6.53, respectively. The isobolographic analysis showed that the three fixed-ratio combinations studied exhibited a synergistic interaction. Furthermore, the gastric damage induced by indomethacin was abolished when this drug was combined with DHA. These data suggest that the systemic administration of the DHA-indomethacin combination induces a synergistic and gastric safety effect.
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Multi-residue and multi-class method for the determination of antibiotics in bovine muscle by ultra-high-performance liquid chromatography tandem mass spectrometry.
Meat Sci.
PUBLISHED: 01-13-2014
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A multi-residue quantitative screening method covering 41 antibiotics from 7 different families, by ultra-high-performance-liquid-chromatography tandem mass spectrometry (UHPLC-MS/MS), is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected after a simple sample preparation of bovine muscle optimized to achieve the best recovery for all compounds. A simple sample treatment was developed consisting in an extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. The methodology was validated, in accordance with Decision 2002/657/EC by evaluating the required parameters: decision limit (CC?), detection capability (CC?), specificity, repeatability and reproducibility. Precision in terms of relative standard deviation was under 20% for all compounds and the recoveries between 91% and 119%. CC? and CC? were determined according the maximum residue limit (MRL) or the minimum required performance limit (MRPL), when required.
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The influence of sulfathiazole on the macroalgae Ulva lactuca.
Chemosphere
PUBLISHED: 01-03-2014
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Sulfonamides (SA) are a class of antibiotics routinely found in environmental matrices and therefore their role as contaminants should be investigated in non-target organisms. With this purpose the present experimental work has evaluated the exposure of the chlorophycean Ulva lactuca L. to sulfathiazole (STZ), a SA drug commonly used in aquaculture, at two concentrations representing prophylactic (25 ?g mL(-1)) and therapeutic (50 ?g mL(-1)) administrations. Results showed that STZ exhibits high stability in seawater with only 18% degradation over the 5d assay at both dosages tested. Also, macroalgae demonstrated an efficient uptake capacity with constant internal concentrations after 24h regardless of the external solutions and thus should be considered as a bioindicator species in risk assessment. Both STZ concentrations induced a slight inhibition of the macroalgae growth after 96 h.
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Comparison among clomipramine, fluoxetine, and placebo for the treatment of anxiety disorders in children and adolescents.
J Child Adolesc Psychopharmacol
PUBLISHED: 12-20-2013
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Abstract Objective: The purpose of this study was to test the efficacy of clomipramine and fluoxetine, controlled by placebo, and compare their action in children and adolescents with anxiety disorders. Method: Thirty subjects (ages 7-17 years), who were diagnosed with generalized anxiety disorder and/or separation anxiety disorder and/or social phobia, were submitted to a 12 week double-blind, randomized, placebo-controlled trial of clomipramine and fluoxetine. The instruments included: the Schedule for Affective Disorders and Schizophrenia, the Multidimensional Anxiety Scale for Children, the Childrens Depression Inventory, the Clinical Global Impressions, and the Childrens Global Assessment Scale. Results: All groups (clomipramine [n=9], fluoxetine [n=10], placebo [n=11]) showed a significant improvement after 12 weeks of treatment. There were significant differences between the fluoxetine and placebo groups in some ratings of anxiety severity and impairment. No significant differences were observed between clomipramine and placebo groups or between fluoxetine and clomipramine groups. Conclusions: Treatment with placebo showed an unusual high response rate. Clomipramine showed similar efficacy compared with fluoxetine, although it was not superior to placebo.
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Molecular epidemiology and genetic diversity of Entamoeba species in a chelonian collection.
J. Med. Microbiol.
PUBLISHED: 11-05-2013
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Veterinarian medicine has recently focused on reptiles because of the existence of captive collections in zoos and an increase in the acquisition of reptiles as pets. The Entamoeba protozoan parasite can causes amoebiasis in various animal species and humans. In reptiles, amoebiasis disease is remarkably rare in most species of chelonians, and crocodiles, and these species may serve as Entamoeba spp. carriers who transmit parasites to susceptible reptile species, such as snakes, and lizards, that can become sick and die. In this study, we identify the Entamoeba species and evaluated their diversity in a population of healthy chelonian (disease-free) by amplification and sequencing of a SSU rDNA region. Through this procedure, three Entamoeba species were identified: E. invadens in 4.76% of chelonians, E. moshkovskii in 3.96% and E. terrapinae in 50%; we did not detect mixed Entamoeba infections. Comparative analysis of the amplified region allowed us to determine the intra-species variations. The E. invadens and E. moshkovskii in this study did not show great difference with respect to the sequences reported in the GeneBank. In E. terrapinae, three different subgroups were identified (A, B and C). Even though subgroups A and C are very alike, subgroup B showed a relative great difference with respect to subgroups A and C (Fst=0.984 and Fst=1.000; 10-14% nucleotide variation by BLAST) and with respect to sequences reported in the GeneBank. These results suggest that E. terrapinae B may be in a process of speciation, or perhaps it belongs to a different linage. However, it is necessary much more work to make a statement of this kind.
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Distribution of PCDD/Fs and dioxin-like PCBs in sediment and plants from a contaminated salt marsh (Tejo estuary, Portugal).
Environ Sci Pollut Res Int
PUBLISHED: 08-07-2013
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Concentrations and profiles of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) were investigated in sediment and plants collected from a salt marsh in the Tejo estuary, Portugal. The highest PCDD/F and dl-PCB concentrations were detected in uncolonized sediments, averaging 325.25?±?57.55 pg g(-1) dry weight (dw) and 8,146.33?±?2,142.14 pg g(-1) dw, respectively. The plants Sarcocornia perennis and Halimione portulacoides growing in PCDD/F and dl-PCB contaminated sediments accumulated contaminants in roots, stems, and leaves. It was observed that PCDD/F and dl-PCB concentrations in roots were significantly lower in comparison with stems and leaves. In general, concentration of ?PCDD/Fs and ?dl-PCBs in H. portulacoides tissues were found to be twofold higher than those in S. perennis, indicating a difference in the accumulation capability of both species. Furthermore, congener profiles changed between sediments and plant tissues, reflecting a selective accumulation of low chlorinated PCDD/Fs and non-ortho dl-PCBs in plants.
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Perceptions of an open visitation policy by intensive care unit workers.
Ann Intensive Care
PUBLISHED: 07-17-2013
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An intensive care unit (ICU) admission is a stressful event for the patient and the patients family. Several studies demonstrated symptoms of anxiety, depression, and posttraumatic stress disorder in family members of patients admitted to ICU. Some studies recognize that the open visitation policy (OVP) is related to a reduction in symptoms of anxiety and depression for the patient and an improvement in family satisfaction. However, some issues have been presented as barriers for the adoption of that strategy. This study was designed to evaluate perceptions of physicians, nurses, and respiratory therapists (RTs) of an OVP and to quantify visiting times in a Brazilian private intensive care unit (ICU).
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Development, optimization and application of an analytical methodology by ultra performance liquid chromatography-tandem mass spectrometry for determination of amanitins in urine and liver samples.
Anal. Chim. Acta
PUBLISHED: 07-06-2013
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Amanitins, highly toxic cyclopeptides isolated from various Amanita species, are the most potent poisons accounting for the hazardous effects on intestinal epithelium cells and hepatocytes, and probably the sole cause of fatal human poisoning. The present study was focused on the development, optimization and application of an analytical methodology by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), following urine and liver sample preparation by protein precipitation with organic solvents, and solid phase extraction (SPE) procedure, for the determination of the amatoxins, ?- and ?-amanitin. Linearity, detection and quantification limits, selectivity, sensitivity, intra and inter-assay precision and recovery were studied, in order to guarantee reliability in the analytical results. The developed method proved to be specific and selective, with LOD (Limit of Detection) values for ?- and ?-amanitin of 0.22 and 0.20 ng mL(-1) in urine and 10.9 and 9.7 ng g(-1) in liver, respectively. LOQ (Limit of Quantification) values ranged from 0.46 to 0.57 ng mL(-1) in urine and 12.3-14.7 ng g(-1) in tissue, for both amanitins. Linearity, in the range of 10.0-200.0 ng mL(-1) or ng g(-1), shows that coefficients of correlation were greater than 0.997 for ?-amanitin and 0.993 for ?-amanitin. Precision was checked at three levels during three consecutive days with intra-day and inter-day coefficients of variation not greater than 15.2%. The extraction recovery presents good results for the concentrations analyzed, with values ranging from 90.2 to 112.9% for both matrices. Thus, the proposed analytical method is innovative, presents a high potential in the identification, detection and determination of ?- and ?-amanitins in urine and tissue samples, as well as in other biological samples, such as kidney and mushrooms.
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Clinical trials in Brazilian journals of ophthalmology: where we are.
Arq Bras Oftalmol
PUBLISHED: 07-02-2013
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To compare clinical trials published in Brazilian journals of ophthalmology and in foreign journals of ophthalmology with respect to the number of citations and the quality of reporting [by applying the Consolidated Standards for Reporting Trials (CONSORT) statement writing standards].
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Synthesis, docking study and relaxant effect of 2-alkyl and 2-naphthylchromones on rat aorta and guinea-pig trachea through phosphodiesterase inhibition.
Bioorg. Chem.
PUBLISHED: 05-29-2013
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Chromone (4), which form the base structure of various flavonoids isolated as natural products, is capable of relaxing smooth muscle. This is relevant to the treatment of high blood pressure, asthma and chronic obstructive pulmonary disease. The former disorder involves the contraction of vascular smooth muscle (VSM), and the latter two bronchoconstriction of airway smooth muscle (ASM). One of the principal mechanisms by which flavonoids relax muscle tissue is the inhibition of phosphodiesterases (PDEs), present in both VSM and ASM. Therefore, a study was designed to analyze the structure-activity relationship of chromone derivatives in vaso- and bronchorelaxation through the inhibition of PDE. Docking studies showed that these chromones bind at the catalytic site of PDEs. Consequently, we synthesized analogs of chromones substituted at position C-2 with alkyl and naphthyl groups. These compounds were synthesized from 2-hydroxyacetophenone and acyl chlorides in the presence of DBU and pyridine, modifying the methodology reported for the synthesis of 3-acylchromones by changing the reaction temperature from 80 to 30°C and using methylene chloride as solvent, yielding the corresponding phenolic esters 10a-10h. These compounds were cyclized with an equivalent of DBU, pyridine as solvent, and heated at reflux temperature, yielding the chromones 11a-11h. Evaluation of the vasorelaxant effect of 4, 11a-11h on rat aorta demonstrated that potency decreases with branched alkyl groups. Whereas the EC50 of compound 11d (substituted by an n-hexyl group) was 8.64±0.39 ?M, that of 11f (substituted by an isobutyl group) was 14.58±0.64 ?M. Contrarily, the effectiveness of the compound is directly proportional to the length of the alkyl chain, as evidenced by the increase in maximal effect of compound 11c versus 11d (66% versus 100%) and 11e versus 11f (60% versus 96%). With an aromatic group like naphthyl as the C-2 substituent, the effectiveness was only 43%. All compounds tested on guinea pig trachea showed less than 55% effectiveness. Compounds 4, 11a-11h were evaluated as PDE inhibitors in vitro, with 11d showing the greatest effect (73%), corroborating the importance of a long alkyl chain, which inhibits the decomposition of cGMP. Docking studies showed that the compound 11d was selective for the inhibition of PDE-5.
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Immunological responses of the mangrove oysters Crassostrea gasar naturally infected by Perkinsus sp. in the Mamanguape Estuary, Paraíba state (Northeastern, Brazil).
Fish Shellfish Immunol.
PUBLISHED: 04-20-2013
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Perkinsus genus includes protozoan parasites of marine mollusks, especially bivalves. In the last four years, this parasite has been detected in mangrove oysters Crassostrea rhizophorae and Crassostrea gasar from the Northeastern region of Brazil. Hemocytes are the key cells of the oyster immune system, being responsible for a variety of cellular and humoral reactions, such as phagocytosis, encapsulation and the release of several effector molecules that control the invasion and proliferation of microorganisms. In Brazil, there is little information on perkinsosis and none on the immune responses of native oysters species against Perkinsus spp. The objective of this study was to determine the effects of natural infection by Perkinsus sp. on the immunological parameters of mangrove oysters C. gasar cultured in the Mamanguape River Estuary (Paraíba, Brazil). Adults oysters (N = 40/month) were sampled in December 2011, March, May, August and October 2012. Gills were removed and used to determine the presence and intensity of the Perkinsus sp. infection, according to a scale of four levels (1-4), using the Rays fluid thioglycollate medium assay. Immunological parameters were measured in hemolymph samples by flow cytometry, including: total hemocyte count (THC), differential hemocyte count (DHC), cell mortality, phagocytic capacity, and production of Reactive Oxygen Species (ROS). The plasma was used to determine the hemagglutination activity. The results showed the occurrence of Perkinsus sp. with the highest mean prevalence (93.3%) seen so far in oyster populations in Brazil. Despite that, no oyster mortality was associated. In contrast, we observed an increase in hemocyte mortality and a suppression of two of the main defense mechanisms, phagocytosis and ROS production in infected oysters. The increase in the percentage of blast-like cells on the hemolymph, and the increase in THC in oysters heavily infected (at the maximum intensity, 4) suggest an induction of hemocytes proliferation. The immunological parameters varied over the studied months, which may be attributed to the dynamics of infection by Perkinsus sp. The results of the present study demonstrate that Perkinsus sp. has a deleterious effect on C. gasar immune system, mainly in high intensities, which likely renders oysters more susceptible to other pathogens and diseases.
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Single nucleotide polymorphism array karyotyping: A diagnostic and prognostic tool in myelodysplastic syndromes with unsuccessful conventional cytogenetic testing.
Genes Chromosomes Cancer
PUBLISHED: 04-05-2013
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Cytogenetic aberrations identified by metaphase cytogenetics (MC) have diagnostic, prognostic, and therapeutic implications in myelodysplastic syndromes (MDS). However, in some MDS patients MC study is unsuccesful. Single nucleotide polymorphism array (SNP-A) based karyotyping could be helpful in these cases. We performed SNP-A in 62 samples from bone marrow or peripheral blood of primary MDS with an unsuccessful MC study. SNP-A analysis enabled the detection of aberrations in 31 (50%) patients. We used the copy number alteration information to apply the International Prognostic Scoring System (IPSS) and we observed differences in survival between the low/intermediate-1 and intermediate-2/high risk patients. We also saw differences in survival between very low/low/intermediate and the high/very high patients when we applied the revised IPSS (IPSS-R). In conclusion, SNP-A can be used successfully in PB samples and the identification of CNA by SNP-A improve the diagnostic and prognostic evaluation of this group of MDS patients. © 2013 Wiley Periodicals, Inc.
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When the body is time: spatial and temporal deixis in children with visual impairments and sighted children.
Res Dev Disabil
PUBLISHED: 03-19-2013
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While there is mounting evidence explaining how concrete concepts are processed, the evidence demonstrating how abstract concepts are processed is rather scant. Most research illustrating how concrete and abstract concepts are processed has been obtained from adult populations. Consequently, not much is known about how these concepts are processed by children, especially those with sensorimotor impairments. This paper reports a study in which groups of children who were either visual-motor impaired (VMG), blind (BG), or sighted (CG) were requested to perform deictic gestures for temporal and spatial concepts. The results showed that: (i) spatial pointing was performed faster than temporal pointing across all groups of children; (ii) such difference in pointing times occurred also within groups; and (iii) the slowest pointing times were those of the blind children followed by the VMG and the CG children, respectively. Additionally, while CG children correctly performed the pointing tasks, VMG and, particularly, BG children relied on a form of deixis known as autotopological (or personal) deixis. The results thus suggest that deprivation or lack of sensorimotor experience with the environment affects the processing of abstract concepts and that a compensatory mechanism may be to rely on the body as a reference frame.
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Prognostic impact of the number of methylated genes in myelodysplastic syndromes and acute myeloid leukemias treated with azacytidine.
Ann. Hematol.
PUBLISHED: 03-05-2013
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The prognostic impact of the aberrant hypermethylation in response to azacytidine (AZA) remains to be determined. Therefore, we have analyzed the influence of the methylation status prior to AZA treatment on the overall survival and clinical response of myeloid malignancies. DNA methylation status of 24 tumor suppressor genes was analyzed by methylation-specific multiplex ligation-dependent probe amplification in 63 patients with myelodysplastic syndromes and acute myeloid leukemia treated with azacytidine. Most patients (73 %) showed methylation of at least one gene, but only 12 % of patients displayed ?3 methylated genes. The multivariate analysis demonstrated that the presence of a high number (?2) of methylated genes (P?=?0.022), a high WBC count (P?=?0.033), or anemia (P?=?0.029) were independent prognostic factors associated with shorter overall survival. The aberrant methylation status did not correlate with the response to AZA, although four of the five patients with ?3 methylated genes did not respond. By contrast, favorable cytogenetics independently influenced the clinical response to AZA as 64.7 % of patients with good-risk cytogenetic abnormalities responded (P?=?0.03). Aberrant methylation status influences the survival of patients treated with AZA, being shorter in those patients with a high number of methylated genes.
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The effects of chloramphenicol on Ulva lactuca.
Chemosphere
PUBLISHED: 02-08-2013
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The administration of pharmacological substances in the food producing industry is a crucial and long established practice in ensuring animal welfare. However, a very high percentage of the drugs used will directly or indirectly be present in the various compartments of natural ecosystems therefore constituting a source of pollution. The reactions that these active compounds may impose on non-target organisms are still widely unknown and further research is essential. Also, new approaches on monitoring are necessary and in this sense, the present work aimed to assess the persistence of chloramphenicol (a banned but illegally used antibiotic) in seawater, together with its effects on the growth of the green macroalgae Ulva lactuca. Moreover, the potential use of this species as a bioindicator was assessed. Results showed CAP presented an exponential degradation pattern in seawater with concentrations decreasing faster than expected. As for the effects on U. lactuca it acted as a growth promoter also contradicting the initial assumptions. Regarding the role of this species in biomonitoring it successfully took up CAP in solution while reflecting the concentrations present conferring it good characteristics as a bioindicator. On the other hand, this ability points to a possibility of CAP being accumulated and transferred along the trophic web through the consumption of U. lactuca by organisms in higher levels.
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Appraisal of space words and allocation of emotion words in bodily space.
PLoS ONE
PUBLISHED: 01-01-2013
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The body-specificity hypothesis (BSH) predicts that right-handers and left-handers allocate positive and negative concepts differently on the horizontal plane, i.e., while left-handers allocate negative concepts on the right-hand side of their bodily space, right-handers allocate such concepts to the left-hand side. Similar research shows that people, in general, tend to allocate positive and negative concepts in upper and lower areas, respectively, in relation to the vertical plane. Further research shows a higher salience of the vertical plane over the horizontal plane in the performance of sensorimotor tasks. The aim of the paper is to examine whether there should be a dominance of the vertical plane over the horizontal plane, not only at a sensorimotor level but also at a conceptual level. In Experiment 1, various participants from diverse linguistic backgrounds were asked to rate the words "up", "down", "left", and "right". In Experiment 2, right-handed participants from two linguistic backgrounds were asked to allocate emotion words into a square grid divided into four boxes of equal areas. Results suggest that the vertical plane is more salient than the horizontal plane regarding the allocation of emotion words and positively-valenced words were placed in upper locations whereas negatively-valenced words were placed in lower locations. Together, the results lend support to the BSH while also suggesting a higher saliency of the vertical plane over the horizontal plane in the allocation of valenced words.
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PhagoSight: an open-source MATLAB® package for the analysis of fluorescent neutrophil and macrophage migration in a zebrafish model.
PLoS ONE
PUBLISHED: 01-01-2013
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Neutrophil migration in zebrafish larvae is increasingly used as a model to study the response of these leukocytes to different determinants of the cellular inflammatory response. However, it remains challenging to extract comprehensive information describing the behaviour of neutrophils from the multi-dimensional data sets acquired with widefield or confocal microscopes. Here, we describe PhagoSight, an open-source software package for the segmentation, tracking and visualisation of migrating phagocytes in three dimensions. The algorithms in PhagoSight extract a large number of measurements that summarise the behaviour of neutrophils, but that could potentially be applied to any moving fluorescent cells. To derive a useful panel of variables quantifying aspects of neutrophil migratory behaviour, and to demonstrate the utility of PhagoSight, we evaluated changes in the volume of migrating neutrophils. Cell volume increased as neutrophils migrated towards the wound region of injured zebrafish. PhagoSight is openly available as MATLAB® m-files under the GNU General Public License. Synthetic data sets and a comprehensive user manual are available from http://www.phagosight.org.
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Purple corn (Zea mays L.) phenolic compounds profile and its assessment as an agent against oxidative stress in isolated mouse organs.
J Med Food
PUBLISHED: 11-14-2011
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This study was designed to determine the contents of total polyphenols, flavonoids, flavonols, flavanols, and anthocyanins of purple corn (Zea mays L.) extracts obtained with different methanol:water concentrations, acidified with 1% HCl (1 N). Another objective was to determine the antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and deoxyribose assay, individual phenolic compounds by high-performance liquid chromatography (HPLC), and endogenous antioxidant enzyme (superoxide dismutase [SOD], catalase [CAT], and total peroxidase [TPX]) activity and lipid peroxidation activity (thiobarbituric acid-reactive substances [TBARS] assay) in isolated mouse organs. Overall, the highest total content of polyphenols, anthocyanins, flavonoids, flavonols, and flavanols was obtained with the 80:20 methanol:water extract, acidified with 1% HCl (1 N). The 50% inhibitory concentration values obtained by the DPPH and ABTS assays with this extract were 66.3??g/mL and 250??g/mL, respectively. The antioxidant activity by the FRAP assay was 26.1??M Trolox equivalents/g, whereas the deoxyribose assay presented 93.6% inhibition. Because of these results, the 80:20 methanol:water extract, acidified with 1% HCl (1 N), was used for the remaining tests. Eight phenolic compounds were identified by HPLC: chlorogenic acid, caffeic acid, rutin, ferulic acid, morin, quercetin, naringenin, and kaempferol. Furthermore, it was observed that the purple corn extract was capable of significantly reducing lipid peroxidation (lower malondialdehyde [MDA] concentrations by the TBARS assay) and at the same time increasing endogenous antioxidant enzyme (CAT, TPX, and SOD) activities in isolated mouse kidney, liver, and brain. On the basis of the results, it was concluded that the purple corn extract contained various bioactive phenolic compounds that exhibited considerable in vitro antioxidant activity, which correlated well with the decreased MDA formation and increase in activity of endogenous antioxidant enzymes observed in the isolated mouse organs. This warrants further in vivo studies with purple corn extracts to assess its antioxidant activity and other bioactivities.
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Detection, accumulation, distribution, and depletion of furaltadone and nifursol residues in poultry muscle, liver, and gizzard.
J. Agric. Food Chem.
PUBLISHED: 11-02-2011
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Nitrofurans were broadly used as an extremely effective veterinary antibiotic especially in pig and poultry production farms. Because of fears of the carcinogenic effects on humans, the nitrofurans were banned from use in livestock production in many countries, including the European Union. The present study examines the accumulation, distribution, and depletion of furaltadone and nifursol and of their tissue-bound metabolites [3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) and 3,5-dinitro-salicylic acid hydrazine (DNSAH), respectively, in poultry edible tissues (muscle, liver, and gizzards) following administration to chickens of therapeutic and subtherapeutic concentrations of both compounds. Nitrofurans determination was performed by high-performance liquid chromatography-diode array detection and liquid chromatography-tandem mass spectrometry, respectively, for feeds and for poultry tissues. Furaltadone and nifursol, in very low concentrations, were found in samples of muscle, liver, and chickens gizzard collected from slaughtered animals after 5 weeks of treatment and no withdrawal time period. When a withdrawal time period of 3 weeks was respected, no detectable nitrofuran parent compounds was observed in all of the studied matrices. For AMOZ, concentrations of 270 ?g/kg in meat, 80 ?g/kg in liver, and 331 ?g/kg in gizzard were determined after administration of a medicated feed with furaltadone (132 mg/kg), 3 weeks after withdrawal of treatment. For DNSAH, the concentration values obtained are much lower than those observed for AMOZ. For meat, liver, and gizzard, DNSAH concentrations of 2.5, 6.4, and 10.3 ?g/kg, respectively, were determined, after administration of a medicated feed with nifursol (98 mg/kg), 3 weeks after withdrawal of treatment. The gizzard could be considered a selected matrix for nitrofuran residues evaluation in poultry, due to its capacity of retaining either nitrofuran parent compounds or metabolites in higher concentrations, regardless of the administered dose or of the respected withdrawal time period.
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Development and validation of a column high-performance liquid chromatography method for quantification of ganaphaliin A and B in inflorescences of Gnaphalium liebmannii Sch. Bp ex Klatt.
J AOAC Int
PUBLISHED: 09-17-2011
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An HPLC method was developed for the simultaneous determination of gnaphaliin A and B, active compounds of Gnaphalium liebmannii Sch. Bp ex Klatt. The HPLC separation was performed on an Inertsil ODS-3 (150 x 4.6 mm id, 5 microm) RP C18 column operated at 40 degrees C; the isocratic mobile phase was 0.02% aqueous orthophosphoric acid-methanol-acetonitrile (50 + 30 + 20, v/v/v), with a run time of 20 min and flow rate of 1.5 mL/min. Detection with a photodiode array detector (PDAD) was at 270 nm. The method was validated for linearity, repeatability, LOD, and LOQ. The LOD and LOQ for gnaphaliin A and B were found to be in the range of 0.4-0.5 and 1.0-1.4 microg/mL, respectively. This is the first report of an analytical method developed for the quantitative analysis of flavones from Gnaphalium species by HPLC-PDAD with applications for raw material and commercial products.
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A LC-MS/MS methodology to determine furaltadone residues in the macroalgae Ulva lactuca.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-18-2011
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Presently, the rise of new contaminants in the environment has widened the scope of pharmaceutical analyses as to face the demanding new challenges. An increasing tendency for the interconnection and overlap of research fields, such as ecology and biochemistry, is intensifying the demand for new methodologies to be applied to the survey of drugs in unconventional matrices. Integrated in this group are macrophytes, such as the green macroalgae Ulva lactuca, which are under study as to ascertain their ability as indicators of contamination for many substances. Nonetheless, methodologies for extraction and determination of drugs in such matrices are scarce and new studies on the subject are pressing. A new methodology for the determination of the antibiotic furaltadone in U. lactuca by liquid chromatography-tandem mass spectrometric (LC-MS/MS) procedure was developed, optimized and validated following the guidelines of the EC Decision 2002/657. The calibration curves showed linearity above 0.99 (R(2)). The relative standard deviations obtained for repeatability, expressed as CV, were between 15.3 and 20.5 and for reproducibility 25.3 and 28.2 whereas accuracy was in the interval of 88.9-95.5 (%). The limit of decision (CC?) and the detection capability (CC?) were respectively 5.57 ?g kg(-1) and 10.97 ?g kg(-1). The method was successfully applied to experimental samples.
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Duality between time series and networks.
PLoS ONE
PUBLISHED: 06-29-2011
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Studying the interaction between a systems components and the temporal evolution of the system are two common ways to uncover and characterize its internal workings. Recently, several maps from a time series to a network have been proposed with the intent of using network metrics to characterize time series. Although these maps demonstrate that different time series result in networks with distinct topological properties, it remains unclear how these topological properties relate to the original time series. Here, we propose a map from a time series to a network with an approximate inverse operation, making it possible to use network statistics to characterize time series and time series statistics to characterize networks. As a proof of concept, we generate an ensemble of time series ranging from periodic to random and confirm that application of the proposed map retains much of the information encoded in the original time series (or networks) after application of the map (or its inverse). Our results suggest that network analysis can be used to distinguish different dynamic regimes in time series and, perhaps more importantly, time series analysis can provide a powerful set of tools that augment the traditional network analysis toolkit to quantify networks in new and useful ways.
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Breaking bad news during prenatal care: a challenge to be tackled.
Cien Saude Colet
PUBLISHED: 06-10-2011
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Communicating an unfavorable diagnosis during prenatal care is a growing challenge in clinical practice, as more and more tests are being performed to screen for the main conditions affecting the pregnant woman and her fetus. The way patients receive and subsequently deal with bad news is directly influenced by how the news is communicated by the attending physician. Unfortunately, physicians receive little or no training in communicating bad news, and they generally feel quite uncomfortable about doing so. Although many physicians consider the saying that "theres no good way to break bad news" to be the truth, the maxim does not reflect the true picture. The scope of this article is to discuss, in light of the scientific literature and the experience of fetal medicine services, some recommendations that can help to deal with these difficult moments and improve patient care for the remainder of the pregnancy.
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Gnaphaliin A and B relax smooth muscle of guinea-pig trachea and rat aorta via phosphodiesterase inhibition.
J. Pharm. Pharmacol.
PUBLISHED: 05-19-2011
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To explore the relaxant mechanism of action of gnaphaliin A and gnaphaliin B in guinea-pig trachea and rat aorta, and to investigate the theoretical and experimental phosphodiesterase (PDE) inhibitory activity of these flavones.
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Isolation of the opdE gene that encodes for a new hydrolase of Enterobacter sp. capable of degrading organophosphorus pesticides.
Biodegradation
PUBLISHED: 05-04-2011
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Microbial enzymes that can hydrolyze organophosphorus compounds have been isolated, identified and characterized from different microbial species in order to use them in biodegradation of organophosphorus compounds. We isolated a bacterial strain Cons002 from an agricultural soil bacterial consortium, which can hydrolyze methyl-parathion (MP) and other organophosphate pesticides. HPLC analysis showed that strain Cons002 is capable of degrading pesticides MP, parathion and phorate. Pulsed-field gel electrophoresis and 16S rRNA amplification were performed for strain characterization and identification, respectively, showing that the strain Cons002 is related to the genus Enterobacter sp. which has a single chromosome of 4.6 Mb and has no plasmids. Genomic library was constructed from DNA of Enterobacter sp. Cons002. A gene called opdE (Organophosphate Degradation from Enterobacter) consists of 753 bp and encodes a protein of 25 kDa, which was isolated using activity methods. This gene opdE had no similarity to any genes reported to degrade organophosphates. When kanamycin-resistance cassette was placed in the gene opdE, hydrolase activity was suppressed and Enterobacter sp. Cons002 had no growth with MP as a nutrients source.
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Late outcomes of mitral repair in rheumatic patients.
Rev Bras Cir Cardiovasc
PUBLISHED: 04-04-2011
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The long-term results after surgical repair of rheumatic mitral valve remain controversial in literature. Our aim was to determine the predictive factors which impact the long-term results after isolated rheumatic mitral valve repair and to evaluate the effect of those factors on reoperation and late mortality.
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[Acute occlusion of a popliteal aneurysm - The value of intra-arterial preoperative thrombolysis].
Rev Port Cir Cardiotorac Vasc
PUBLISHED: 04-01-2011
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In this paper it is presented a clinical report on intra-arterial thrombolysis of an acute thrombosed popliteal artery aneurysm. We report the technical aspects and discuss indications, principal advantages and contraindications of this form of treatment.
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[Fatal rickets in the fetus and undiagnosed maternal celiac disease].
Gastroenterol Hepatol
PUBLISHED: 03-25-2011
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Celiac disease is a relatively frequent enteropathy associated with a wide range of clinical manifestations, due in part to malabsorption. In women, it has been associated with obstetric and gynecological alterations such as repeated miscarriages, intrauterine growth delay, premature delivery, and low birth weight. We present the case of a woman with undiagnosed celiac disease who gave birth to a stillborn foetus via normal delivery after 34 weeks of gestation. The foetus presented severe morphological alterations due to hypomineralization which were compatible with rickets. In the medical literature congenital rickets secondary to maternal celiac disease due to malabsorption is rare. We discuss the current knowledge on maternofoetal phospho-calcium metabolism and relate active celiac disease with severe hypocalcaemia during pregnancy and fatal rickets in the foetus. We recommend screening for celiac disease in pregnant women with signs of malabsorption or impaired fetal development.
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Selection of the derivatization reagent--the case of human blood cholesterol, its precursors and phytosterols GC-MS analyses.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 03-11-2011
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Phytosterols (PS; ?-sitosterol and campesterol) and cholesterol precursors (CP; desmosterol and lathosterol) have been suggested as important biochemical markers of cholesterol intestinal absorption and liver biosynthesis, respectively. Given that these compounds appear in human blood in low amounts, sensitive and accurate methodology is required, such as gas chromatography-mass spectrometry (GC-MS) the most frequently used. One of the most critical factors of the GC analytical determination is the step of derivatization. Thus, the main objective of the present study was compare and select the better (one out of three) silylation mixtures as follows: N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide/ammonium iodide (MTBSTFA:NH(4)I), N-O-bis-(trimethylsilyl) trifluoroacetamide/trimethylchlorosilane (BSTFA:TMCS), and N-methyl-N-(trimethylsilyl)-trifluoroacetamide/1,4-dithioerythritol/trimethyliodosilane (MSTFA:DTE:TMIS). The results of this study are discussed and accompanied by a brief review on the importance and principles of derivatization process, specifically in silylation reactions in GC-MS sterols analyses. Furthermore, a scrutiny of some published results is presented, along with additional information about mass spectral data of these potentially useful compounds. Interestingly, the results of the study showed that from the three validated methodologies, the selected one, based on the best relation specificity/sensibility, is MSTFA:DTE:TMIS. With this silylation procedure for simultaneous determination of PS and CP in human serum by GC-MS in selected ion monitoring (SIM) mode, good linearity (r(2)?0.931), precision (repeatability ranging from 0.92 to 3.91 CV and intermediate precision ranging from 5.12 to 6.33) and recoveries (?93.6%) were obtained. Thus, it proved to be a helpful methodology in the quantification of predominant serum cholesterol origin in each patient.
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Prognostic impact of severe thrombocytopenia in low-risk myelodysplastic syndrome.
Cancer
PUBLISHED: 01-31-2011
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Thrombocytopenia is very common in myelodysplastic syndrome (MDS); however, its clinical impact in low-risk patients remains controversial.
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A 7-year survey of superficial and cutaneous mycoses in a public hospital in Natal, Northeast Brazil.
Braz. J. Microbiol.
PUBLISHED: 01-10-2011
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In the present study, we determined the frequency of superficial and cutaneous mycoses and their etiologic agents during a 7-year period (2002-2008) in Natal, Brazil. A total of 1,717 specimens of skin, nail, and hair were collected from 1,382 patients with suspected mycoses lesions and were then subjected to direct microscopy and culture.
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PCDD/Fs and dioxin-like PCBs in sediment and biota from the Mondego estuary (Portugal).
Chemosphere
PUBLISHED: 01-09-2011
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The concentrations of 17 polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in sediment and key species as an initial investigation on PCDD/Fs and dl-PCBs contamination in the Mondego estuary (Portugal). The results demonstrated that the values of the total PCDD/Fs (?PCDD/Fs) concentrations were considerably lower than those of the sum of dl-PCBs (?dl-PCBs) in all the studied samples. Regarding the contribution of individual congeners, OCDD was the predominant PCDD/F and the mono-ortho PCB 118 and PCB 105 were the dominant PCBs in the majority of the samples. Our results suggest that PCDD/Fs and PCBs behave quite differently along the aquatic food web: ?PCDD/Fs concentrations were lower in higher trophic-level organisms with fish presenting a distinct PCDD/Fs congeners profile; on the contrary, the higher ?dl-PCBs values were found in upper-level biota, although not exclusively, and quite similar dl-PCBs congener profiles were observed in nearly all the studied species.
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Cytogenetic risk stratification in chronic myelomonocytic leukemia.
Haematologica
PUBLISHED: 11-25-2010
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The prognostic value of cytogenetic findings in chronic myelomonocytic leukemia is unclear. Our purpose was to evaluate the independent prognostic impact of cytogenetic abnormalities in a large series of patients with chronic myelomonocytic leukemia included in the database of the Spanish Registry of Myelodysplastic Syndromes.
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Hemodynamic and perfusion end points for volemic resuscitation in sepsis.
Shock
PUBLISHED: 08-18-2010
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Sepsis is the systemic inflammatory response syndrome secondary to a local infection, and severe sepsis and septic shock are the more devastating scenarios of this disease. In the last decade, considerable achievements were obtained in sepsis knowledge, and an international campaign was developed to improve the treatment of this condition. However, sepsis is still one of the most important causes of death in intensive care units. The early stages of sepsis are characterized by a variety of hemodynamic derangements that induce a systemic imbalance between tissue oxygen supply and demand, leading to global tissue hypoxia. This dysfunction, which may occur in patients presenting normal vital signs, can be accompanied by a significant increase in both morbidity and mortality. The early identification of high-risk sepsis patients through tissue perfusion markers such as lactate and venous oxygen saturation is crucial for prompt initiation of therapeutic support, which includes early goal-directed therapy as necessary. The purpose of this article was to review the most commonly used hemodynamic and perfusion parameters for hemodynamic optimization in sepsis, emphasizing the physiological background for their use and the studies that demonstrated their effectiveness as goals of volemic resuscitation.
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The effects of the nitrofuran furaltadone on Ulva lactuca.
Chemosphere
PUBLISHED: 06-14-2010
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The use of pharmaceuticals in the food production industry as prophylatic and therapeutic agents is necessary to promote animal health, but may entail significant consequences to natural ecosystems, especially in the cases of overdosing and use of banned pharmaceuticals. The vast effects that antibiotics released into the environment have on non-target organisms are already under the scope of researchers but little attention has been given to primary producers such as macroalgae. The present study assessed furaltadones, an antibacterial agent illegally used for veterinary purposes, uptake capacity by Ulva lactuca and its effect in the growth of this cosmopolitan macroalgae. Differences in macroalgal growth were shown when submitted to prophylactic and therapeutic concentrations of furaltadone in the water (16 and 32 ?g mL?¹, respectively). The therapeutic concentration caused higher growth impairment than the prophylactic treatment did, with 87.5% and 58% reductions respectively. Furthermore, together with data collected from the accumulation assays, with values of internal concentrations as high as 18.84 ?g g?¹ WW, suggest that the macroalgae U. lactuca should be included in field surveys as a biomonitor for the detection of nitrofurans.
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Water quality characterization in real biofilm wastewater treatment systems by particle size distribution.
Bioresour. Technol.
PUBLISHED: 04-05-2010
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This article analyses the relation between wastewater quality parameters and particle size distribution (PSD) in three real wastewater treatment plants with different biofilm technologies: submerged biofilter system, trickling filter system, and rotating biological contactor system. The main quality parameters, (suspended solids, turbidity and COD), and PSD in the influent and effluent water of each different biofilm treatment were analyzed during 1year. The PSD was fitted using the power law (n(d(p))= partial differentialN(d(p))/ partial differentiald(p)=A x d(p)(-)(b)(Log(d)(p)())) obtaining the coefficients A and b to define the particle distribution. Mathematical correlations between this coefficients and the rest of parameters studied were found (SS=0.0713 x A(0.585), turbidity=4.549 x 10(-4) x A(1.096), COD=0.0201 x A(0.774)). The relation with the average particle size by mass was also found, (d(pma)=60.3137 x b(-2.242)). Moreover a relation between PSD and the particle elimination efficiency of the secondary treatment was study, (eta=2.844-2.498 x b(relative)+0.0863 x A(relative)). These expressions are very useful to understand the behavior of the biofilm treatment system using PSD analyses.
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The effects of modified ultrafiltration on pulmonary function and transfusion requirements in patients underwent coronary artery bypass graft surgery.
Rev Bras Cir Cardiovasc
PUBLISHED: 02-22-2010
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The inflammatory response after cardiac surgery increases vascular permeability leading to higher mortality and morbidity in the post operative time. The modified ultrafiltration (MUF) had shown benefits on respiratory, and hemodynamic in pediatric patients. This approach in adults is not well established yet. We hypothesize that modified ultrafiltration may improve respiratory, hemodynamic and coagulation function in adults after cardiac surgeries.
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Molecular modeling study of isoindolines as L-type Ca(2+) channel blockers by docking calculations.
J Mol Model
PUBLISHED: 02-12-2010
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Two series of isoindolines 1(a-g) and 2(a-g) were found by docking calculations to be possible L-type Ca(2+) channel (LCC) blockers. The theoretical 3-D model of the outer vestibule and the selective filter of the LCC was provided by Professor Lipkind; this model consists of transmembrane segments S5 and S6 and P-loops contributed by each of four repeats (I, II, III, and IV) of Ca(v) 1.2. Therefore, two well-known LCC blockers, nifedipine 3 and (R)-ethosuccinimide 4 were also evaluated, and their binding sites on the LCC were identified and compared with those obtained for 1(a-g) and 2(a-g). Analysis of the results shows that the target compounds tested probably could be LCC blockers, since they interact with or near the glutamic acid residues Glu393, Glu736, Glu1145 and Glu1446 (the EEEE locus), which belong to the LCC selectivity region. The G values for all of the Ca(2+) channel ligands are between-10.78 and -3.67 (kcal mol(-1)), showing that LCC-1b, -1e and -1f complexes are more stable than the other compounds tested. Therefore, theoretically calculated dissociation constants K(d) (microM) were obtained for all compounds. Comparing these values reveals that compounds 1b (0.0244 microM), 1e (0.0176 microM) and 1f (0.0125 microM) exhibit more affinity for the LCC than the other compounds. This screening shows that the two series of isoindolines probably could act as LCC blockers.
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Prolonged survival with improved tolerability in higher-risk myelodysplastic syndromes: azacitidine compared with low dose ara-C.
Br. J. Haematol.
PUBLISHED: 02-05-2010
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In the phase III AZA-001 trial, low-dose cytarabine (LDara-C), the most widely used low-dose chemotherapy in patients with higher-risk myelodysplastic syndrome (MDS) who are ineligible for intensive treatment, was found to be associated with poorer survival compared with azacitidine. This analysis further compared the efficacy and the toxicity of these two drug regimens. Before randomization, investigators preselected patients to receive a conventional care regimen, one of which was LDara-C. Of 94 patients preselected to LDara-C, 45 were randomized to azacitidine and 49 to LDara-C. Azacitidine patients had significantly more and longer haematological responses and increased red blood cell transfusion independence. Azacitidine prolonged overall survival versus LDara-C in patients with poor cytogenetic risk, presence of -7/del(7q), and French-American-British subtypes refractory anaemia with excess blasts (RAEB) and RAEB in transformation. When analyzed per patient year of drug exposure, azacitidine treatment was associated with fewer grade 3-4 cytopenias and shorter hospitalisation time than LDara-C in these higher-risk MDS patients.
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On the mental representations originating during the interaction between language and vision.
Cogn Process
PUBLISHED: 01-23-2010
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The interaction between vision and language processing is clearly of interest to both cognitive psychologists and psycholinguists. Recent research has begun to create understanding of the interaction between vision and language in terms of the representational issues involved. In this paper, we first review some of the theoretical and methodological issues in the current vision-language interaction debate. Later, we develop a model that attempts to account for effects of affordances and visual context on language-scene interaction as well as the role of sensorimotor simulation. The paper addresses theoretical issues related to the mental representations that arise when visual and linguistic systems interact.
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BAALC is an important predictor of refractoriness to chemotherapy and poor survival in intermediate-risk acute myeloid leukemia (AML).
Ann. Hematol.
PUBLISHED: 09-28-2009
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We have analyzed brain and acute leukemia, cytoplasmic (BAALC) gene expression and other genetic markers (ERG, EVI1, MN1, PRAME, WT1, FLT3, and NPM1 mutations) in 127 intermediate-risk acute myeloid leukemia (AML) patients: 98 cytogenetically normal and 29 with intermediate-risk cytogenetic alterations. High versus low BAALC expressers showed a higher refractoriness to induction treatment (31% vs 10%; p = .005), lower complete remission rate after salvage therapy (82% vs 97%; p = .010), and lower 3-year overall (23% vs 58%, p < .001) and relapse-free survival (26% vs 52%, p = .006). Similar results were found when cytogenetic subgroups were analyzed separately. Multivariate models confirmed the unfavorable prognosis of this marker. In conclusion, BAALC is a relevant prognostic marker in intermediate-risk AML.
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Sonographic findings in a case of tetrasomy 9p associated with increased nuchal translucency and Dandy-Walker malformation.
J Clin Ultrasound
PUBLISHED: 08-06-2009
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We report a case of a 23-year-old pregnant woman, who underwent amniocentesis after ultrasound (US) examination in the first trimester which revealed a nuchal translucency thickness of 2.9 mm. Cytogenetic analysis revealed complete tetrasomy of the short arm of chromosome 9. Further US evaluation in the second trimester revealed Dandy-Walker malformation, ventriculomegaly, bilateral clubfoot, lip and palate clefts, arthrogryposis and hyperechoic kidneys with bilateral pelvic dilatation. At 30 weeks of gestation, a placental abruption was noted and a Cesarean section was performed. The infant died shortly after birth. A review of previous cases of tetrasomy 9p shows that the remarkable sonographic findings are ventriculomegaly, intrauterine growth restriction, genitourinary anomaly, Dandy-Walker malformation, cleft lip/palate and limb malformation, but the association of tetrasomy 9p and increased nuchal translucency had not been reported.
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[Method to calculate the additional hospital stay in patients with cross infection].
Rev Med Inst Mex Seguro Soc
PUBLISHED: 06-11-2009
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To calculate additional hospital stay due to specific cross infection.
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Solving the confusion of gnaphaliin structure: gnaphaliin A and gnaphaliin B identified as active principles of Gnaphalium liebmannii with tracheal smooth muscle relaxant properties.
J. Nat. Prod.
PUBLISHED: 06-10-2009
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Inflorescences of Gnaphalium liebmannii, commonly known as "Gordolobo", is the most important remedy in Mexican traditional medicine to treat respiratory diseases, including asthma. By a bioguided fractionation of the n-hexane extract of this plant, following the relaxant effect on guinea pig tracheal smooth muscle, the flavones 5,7-dihydroxy-3,8-dimethoxyflavone (1) and 3,5-dihydroxy-7,8-dimethoxyflavone (2) were identified as the active relaxant compounds. Compounds 1 and 2 showed more potent relaxant properties than aminophylline in this model. Both 1 and 2 have been described as gnaphaliin in the past; here EIMS data, NMR experiments for both compounds, and X-ray diffraction analysis for 1 provided structural information to suggest that 1 and 2 should be named gnaphaliins A and B, respectively.
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Development of an analytical methodology for simultaneous determination of vincristine and doxorubicin in pharmaceutical preparations for oncology by HPLC-UV.
J Chromatogr Sci
PUBLISHED: 05-30-2009
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A high-performance liquid chromatography-UV methodology (lambda=230 nm) was developed and validated for the simultaneous determination of vincristine and doxorubicin in pharmaceutical preparations used in oncology. The chromatography was carried out on a C18 column using acetonitrile 90% in water-potassium hydrogenphosphate buffer 50 mM, pH 3.2+/-0.1 (32:68, v/v) as mobile phase at a flow rate of 1.5 mL/min. The method proved to be specific, exact, and accurate, in accordance with the ICH standards, presenting linearity in the 1-5 microg/mL and 5-100 microg/mL intervals, and detection (0.19x0.51 microg/mL) and quantification (0.63x1.7 microg/mL) limits for vincristine and doxorubicin, respectively.
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Molecular stratification model for prognosis in cytogenetically normal acute myeloid leukemia.
Blood
PUBLISHED: 04-27-2009
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We have evaluated 9 new molecular markers (ERG, EVI1, MLL-PTD, MN1, PRAME, RHAMM, and WT1 gene-expression levels plus FLT3 and NPM1 mutations) in 121 de novo cytogenetically normal acute myeloblastic leukemias. In the multivariate analysis, high ERG or EVI1 and low PRAME expressions were associated with a shorter relapse-free survival (RFS) and overall survival (OS). A 0 to 3 score was given by assigning a value of 0 to favorable parameters (low ERG, low EVI1, and high PRAME) and 1 to adverse parameters. This model distinguished 4 subsets of patients with different OS (2-year OS of 79%, 65%, 46%, and 27%; P = .001) and RFS (2-year RFS of 92%, 65%, 49%, and 43%; P = .005). Furthermore, this score identified patients with different OS (P = .001) and RFS (P = .013), even within the FLT3/NPM1 intermediate-risk/high-risk subgroups. Here we propose a new molecular score for cytogenetically normal acute myeloblastic leukemias, which could improve patient risk-stratification.
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High FOXO3a expression is associated with a poorer prognosis in AML with normal cytogenetics.
Leuk. Res.
PUBLISHED: 03-03-2009
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The PI3/AKT pathway is up-regulated in acute myeloid leukemia (AML), but its prognostic relevance in cytogenetically normal AML (CN-AML) is unclear. We evaluated RNA levels of AKT and two downstream substrates (FOXO3a-p27) in 110 de novo CN-AML, included in the Spanish PETHEMA therapeutic protocols. Patients with high FOXO3a gene expression displayed shorter OS (p=0.015) and RFS (p=0.048) than low FOXO3a expressers. Features selected in the multivariate analysis as having an independent prognostic value for a shorter survival were WBC>50x10(9)/L, age >65 years and high FOXO3a expression. We concluded that FOXO3a assessment could contribute to improve the molecular-based risk stratification in CN-AML.
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[Health and disease processes among institutionalized children: an ecological vision].
Cien Saude Colet
PUBLISHED: 02-07-2009
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This article discusses aspects of health and disease processes among children attended in a child shelter of the city of Belém between 2004 and 2005. The data were collected from documental sources and through interviews with technicians of the institution. From a total of 287 children, 49.47% presented diseases, deficiencies and injuries when being admitted to the shelter, probably associated to the situation of poverty and negligence they were exposed to since they were born. During their permanence in the shelter, it was verified that the children contracted infecto-contagious diseases (42.5%) and manifested problems of emotional nature (18.83%) that can be related to the environmental characteristic of the institution - inadequate proportion adult/children (1:8) and overcrowding (75/month). The results allow concluding that the childrens health conditions reflect the situation of material and emotional privation to which they were exposed when living with the family and during their permanence in the shelter. In this sense, the health and disease processes are discussed from an ecological perspective that recognizes the biological, social and cultural factors that constitute the family and the shelter as developmental contexts of the institutionalized child.
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Two different chitinase genotypes in a patient with an amebic liver abscess: a case report.
Am. J. Trop. Med. Hyg.
PUBLISHED: 01-15-2009
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The present work deals with the identification of a patient with two liver abscesses containing two different strains of Entamoeba histolytica, as defined by chitinase gene plymorphisms.
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Clenbuterol storage stability in the bovine urine and liver samples used for European official control in the azores islands (portugal).
J. Agric. Food Chem.
PUBLISHED: 01-14-2009
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Clenbuterol is a well-known growth promoter, illegally used in farm animals, especially in cattle. Samples collected for the screening of beta(2)-agonist residues in Portuguese Azores Islands must travel through all the nine islands until they reach Azores Central Laboratory. If any suspicious sample is detected, it must be further transported to the National Reference Laboratory in Lisbon for confirmation. As a consequence of these circumstances, samples are submitted to different transport and storage times, as well as different temperature conditions and in some cases successive freezing and thawing cycles. As clenbuterol is the most detected beta(2)-agonist growth promoter in the Portuguese Residue Monitoring Plan, studies were conducted on the stability of this compound in incurred samples (bovine liver and urine) at +4, -20 and -60 degrees C over time. Samples kept at -20 degrees C were also analyzed over time after successive freezing and thawing cycles. The analyses of clenbuterol over time were performed by gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM). Clenbuterol in incurred urine and liver samples was significantly stable up to 20 weeks at -20 and -60 degrees C and after, at least, six consecutive freezings and thawings. At +4 degrees C, clenbuterol remained stable, at least until 12 weeks in urine and up to 20 weeks in liver.
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Bleeding in non-ST-segment elevation acute coronary syndrome.
Rev Bras Ter Intensiva
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The development of antiplatelet and antithrombotic therapies, in addition to interventionist strategy, has resulted in great improvements in the outcomes of patients with non-ST-segment elevation acute coronary syndrome. Parallel to therapeutic advances, bleeding, which can be induced during management, increases the risk of recurrent ischemia, myocardial infarction and death. The present literature review describes the benefits and bleeding risks of each medication or intervention strategy and suggests guidelines for managing these patients.
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Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia.
Rev Bras Cir Cardiovasc
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Several techniques and cardioplegic solutions have been used for heart preservation during transplant procedures. Unfortunately, there is a lack of ideal method for myocardial preservation in the clinical practice. The use of retrograde cardioplegia provides continuous infusion of cardioplegic solution during the graft implantation. This strategy may provide better initial recovery of the graft. The objective of this study is to describe the experience of a single center where all patients received the same solution for organ preservation and were subjected to continuous retrograde blood microcardioplegia during implantation of the graft and to evaluate factors associated to early and late mortality with this technique.
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Perkinsus sp. infecting oyster Crassostrea rhizophorae (Guilding, 1828) on the coast of Bahia, Brazil.
J. Invertebr. Pathol.
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This study investigated the occurrence of the protozoan Perkinsus in the oyster Crassostrea rhizophorae on the coast of Bahia State, Brazil. The oysters (n = 900) were collected in February-March and July-August 2010. The Rays fluid thioglycollate medium (RFTM) analysis of gills and rectum revealed hypnospores of Perkinsus sp. with a high mean prevalence (63%). The infection intensity varied from very light to advanced. The polymerase chain reaction confirmed Perkinsus in 87.2% of the RFTM-positive oysters. Histological analysis showed trophozoites and schizonts phagocytized by hemocytes, mainly in the intestine and the stomach epithelium.
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Advances in analytical methods to study cholesterol metabolism: the determination of serum noncholesterol sterols.
Biomed. Chromatogr.
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Cholesterol biosynthesis precursors and plant sterols are noncholesterol sterols currently used as relative surrogate markers of cholesterol synthesis and absorption, respectively. Its determination in serum samples is a way of diagnosing inherited disorders and also a tool for health evaluation during lipid-lowering lifestyle/drug therapy monitoring. This approach is the only one that can be used for large-scale clinical trials or population based studies, but, nevertheless, there is no reference method for the quantification of noncholesterol sterols in human serum samples and only analysis by GC-FID and GC-MS has been reported to be completely validated. Although there has been a wider use of noncholesterol sterols for the measurement and characterization of cholesterol metabolism, there is a lack of harmonization of measurements and of standardization of the methodology, which is essential for routine measurements of diagnostic utility. New recent advances in analytical methods for the determination of serum noncholesterol sterols are highlighted, focusing on the sample preparation, separation and detection techniques, which will enhance the range of applications in clinical practice.
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Ventricular pacing threshold after transthoracic external defibrillation with two different waveforms: an experimental study.
Europace
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Although an increase in the ventricular pacing threshold (VPT) has been observed after administration of transthoracic shock for ventricular defibrillation, few studies have evaluated the phenomenon with respect to the defibrillation waveform energy. Therefore, this study examined the VPT behaviour after transthoracic shock with a monophasic or biphasic energy waveform.
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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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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.