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Find video protocols related to scientific articles indexed in Pubmed.
Dengue fever in Europe: could there be an epidemic in the future?
Expert Rev Anti Infect Ther
PUBLISHED: 11-18-2014
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Dengue virus (DENV) is the arbovirus with the widest impact on human health. Although its dispersal is partially conditioned by environmental constraints that limit the distribution of its main vector (Aedes aegypti), DENV has been spreading geographically in recent times, but mostly afflicting tropical and subtropical regions. With no prophylactic vaccine or specific therapeutics available, vector control remains the best alternative to restrain its circulation. Moreover, the establishment of thriving vector populations in peri urban environments brings humans and viruses together, opening the possibility for the occurrence of unexpected outbreaks. Europe is no exception: such was the case of Madeira in 2012. In addition to its impact on the health of the local population, health services, and economy, this outbreak revealed how difficult it may be to control the circulation of pathogenic arboviruses, especially taking into consideration that Europe is already partially colonized by another DENV vector, Aedes albopictus.
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Global longitudinal strain as a potential prognostic marker in patients with chronic heart failure and systolic dysfunction.
Rev Port Cardiol
PUBLISHED: 08-23-2014
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The prognostic value of myocardium deformation measurements in chronic heart failure (CHF) is still poorly addressed. The purpose of this study was to evaluate the correlation of left ventricular (LV) global longitudinal strain (GLS) with clinical and prognostic indicators in patients with CHF and systolic dysfunction.
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Metapopulations in temporary streams - The role of drought-flood cycles in promoting high genetic diversity in a critically endangered freshwater fish and its consequences for the future.
Mol. Phylogenet. Evol.
PUBLISHED: 08-12-2014
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Genetic factors have direct and indirect impacts in the viability of endangered species. Assessing their genetic diversity levels and population structure is thus fundamental for conservation and management. In this paper we use mitochondrial and nuclear markers to address phylogeographic and demographic data on the critically endangered Anaecypris hispanica, using a broad sampling set which covered its known distribution area in the Iberian Peninsula. Our results showed that the populations of A. hispanica are strongly differentiated (high and significant ?ST and FST values, corroborated by the results from AMOVA and SAMOVA) and genetically diversified. We suggest that the restricted gene flow between populations may have been potentiated by ecological, hydrological and anthropogenic causes. Bayesian skyline plots revealed a signal for expansion for all populations (tMRCA between 68kya and 1.33Mya) and a genetic diversity latitudinal gradient was detected between the populations from the Upper (more diversified) and the Lower (less diversified) Guadiana river basin. We postulate a Pleistocenic westwards colonization route for A. hispanica in the Guadiana river basin, which is in agreement with the tempo and mode of paleoevolution of this drainage. The colonization of River Guadalquivir around 60kya with migrants from the Upper Guadiana, most likely by stream capture, is also suggested. This study highlights the view that critically endangered species facing range retreats (about 47% of its known populations have disappeared in the last 15years) are not necessarily small and genetically depleted. However, the extinction risk is not negligible since A. hispanica faces the combined effect of several deterministic and stochastic negative factors and, moreover, recolonization events after localized extinctions are very unlikely to occur due to the strong isolation of populations and to the patchily ecologically-conditioned distribution of fish. The inferred species distribution models highlight the significant contribution of temperature seasonality and isothermality to A. hispanica occurrence in Guadiana environments and emphasize the importance of stable climatic conditions for the preservation of this species. Given the strong population structure, high percentage of private haplotypes and virtual absence of inter-basin gene flow we suggest that each A. hispanica population should be considered as an independent Operational Conservation Unit and that ex-situ and in-situ actions should be conducted in parallel to allow for the long-term survival of the species and the preservation of the genetic integrity of its populations.
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First report of an exophilic Anopheles arabiensis population in Bissau city, Guinea-Bissau: recent introduction or sampling bias?
Malar. J.
PUBLISHED: 08-08-2014
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The malaria vector Anopheles arabiensis exhibits greater behavioural and ecological plasticity than the other major vectors of the Anopheles gambiae complex, which presents challenges for major control methods. This study reports for the first time the presence of An. arabiensis in Antula, a suburb of Bissau city, the capital of Guinea Bissau, where high levels of hybridization between Anopheles coluzzii and An. gambiae have been reported. Given that previous surveys in the area, based on indoor collections, did not sample An. arabiensis, the possibility of a recently introduced exophilic population was investigated.
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Large right ventricular thrombus.
Acta Med Port
PUBLISHED: 06-30-2014
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Right ventricular thrombosis is a rare yet potentially fatal condition. It has been described in association with hypercoagulability states, autoimmune diseases and dilated cardiomyopathy. Echocardiography constitutes the election tool for diagnosis and characterization of these entities, allowing for the differentiation between the various types of thrombi. We present a case of a patient with alcoholic dilated cardiomyopathy admitted for congestive heart failure and lower respiratory infection. In the diagnostic approach, a routine echocardiography revealed a large mural right ventricular thrombus in association with severe biventricular dysfunction. The patient was proposed for anticoagulation strategy, which he refused.
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Post-cardiac injury syndrome following transvenous pacing: case report.
Rev Port Cardiol
PUBLISHED: 06-13-2014
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Post-cardiac injury syndrome (PCIS) is an inflammatory process involving the pericardium secondary to cardiac injury. It can develop after cardiac trauma, cardiac surgery, myocardial infarction, and, rarely, after certain intravascular procedures. We report a rare case of an iatrogenic cardiac rupture followed by PCIS with delayed inflammatory pericardial effusion after pacemaker implantation. A comprehensive literature review on this topic is provided.
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Iron deficiency status irrespective of anemia: a predictor of unfavorable outcome in chronic heart failure patients.
Cardiology
PUBLISHED: 06-07-2014
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To assess the prognostic significance of iron deficiency (ID) in a chronic heart failure (CHF) outpatient population.
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Telemonitoring in heart failure: a state-of-the-art review.
Rev Port Cardiol
PUBLISHED: 05-13-2014
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Heart failure is associated with high costs which are mainly the result of recurrent hospital admissions. New strategies to detect early decompensation and prevent heart failure-related hospitalizations and reduce total health care costs are needed. Telemonitoring is a novel tool based on the use of recent communication technologies to monitor simple clinical variables, in order to enable early detection of heart failure decompensation, providing an opportunity to prevent hospitalization. From conventional telemonitoring to more recent strategies using implantable cardiac devices or implantable hemodynamic monitors, the subject is under active investigation. Despite the beneficial effects reported by meta-analyses of small non-controlled studies, major randomized controlled trials have failed to demonstrate a positive impact of this strategy. Additionally, evidence regarding the value of newer monitoring devices is somewhat contradictory, as some studies show benefits in prognosis which are not confirmed by others. This paper provides an overview of the existing evidence on telemonitoring in heart failure and a comprehensive state-of-the-art discussion on this topic.
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Effects of Echium plantagineum L. bee pollen on basophil degranulation: relationship with metabolic profile.
Molecules
PUBLISHED: 05-07-2014
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This study aimed to evaluate the anti-allergic potential of Echium plantagineum L. bee pollen and to characterize its primary metabolites. The activity of E. plantagineum hydromethanolic extract, devoid of alkaloids, was tested against ?-hexosaminidase release in rat basophilic leukemic cells (RBL-2H3). Two different stimuli were used: calcium ionophore A23187 and IgE/antigen. Lipoxygenase inhibitory activity was evaluated in a cell-free system using soybean lipoxygenase. Additionally, the extract was analysed by HPLC-UV for organic acids and by GC-IT/MS for fatty acids. In RBL-2H3 cells stimulated either with calcium ionophore or IgE/antigen, the hydromethanolic extract significantly decreased ?-hexosaminidase release until the concentration of 2.08 mg/mL, without compromising cellular viability. No effect was found on lipoxygenase. Concerning extract composition, eight organic acids and five fatty acids were determined for the first time. Malonic acid (80%) and ?-linolenic acid (27%) were the main compounds in each class. Overall, this study shows promising results, substantiating for the first time the utility of intake of E. plantagineum bee pollen to prevent allergy and ameliorate allergy symptoms, although a potentiation of an allergic response can occur, depending on the dose used.
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A simple heat dissociation method increases significantly the ELISA detection sensitivity of the nonstructural-1 glycoprotein in patients infected with DENV type-4.
J. Virol. Methods
PUBLISHED: 02-18-2014
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The secreted form of the dengue virus (DENV) nonstructural-1 (NS1) glycoprotein has been shown to be useful for the diagnosis of DENV infections in patients' serum samples. In a number of studies, the sensitivity of the commercially available DENV NS1 glycoprotein detection assays was higher against some DENV serotypes (DENV-1>DENV-3>DENV-2=DENV-4) than others and were also lower using patients' serum samples with secondary versus primary DENV infections. In this study, 471 DENV-4 positive acute phase patients' serum samples were selected from a large panel collected in Brazil from March 2011 to October 2012 by RT-PCR and/or virus isolation followed by serotype determination. The sera from primary (n=228) and secondary (n=238) DENV-4 infections were identified using IgM and IgG capture ELISAs. The sensitivity of a commercial DENV NS1 glycoprotein detection ELISA was then assessed when these serum samples were not pre-treated or pre-treated by acid or heat dissociation prior to being tested. Acid and heat dissociation of patients' serum samples with primary and secondary DENV-4 infections increased significantly the sensitivity of the DENV NS1 glycoprotein detection ELISA from 54.4% to 77.2% (p<0.05) and 82% (p<0.05) and from 39.1% to 63.9% (p<0.05) and 73.1% (p<0.05), respectively. Treatment of DENV infected patients' serum samples using simple and rapid heat dissociation step (100°C for 5min) was, therefore, shown to be very useful for increasing the sensitivity of the DENV NS1 glycoprotein detection ELISA using serum samples from either primary or secondary DENV infected patients.
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The usefulness of the head-up tilt test in patients with suspected epilepsy.
Seizure
PUBLISHED: 02-07-2014
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It is estimated that approximately 20-30% of patients diagnosed with epilepsy have been misdiagnosed, and neurocardiogenic syncope (NCS) might frequently be the real cause of transient loss of consciousness (TLOC) episodes. We assessed the role of the head-up tilt test (HUTT) in patients previously diagnosed with refractory epilepsy to evaluate the ability of this test to correctly diagnose patients with NCS.
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Intramuscular lipoma of the subscapularis muscle.
Sao Paulo Med J
PUBLISHED: 01-30-2014
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Intramuscular lipomas are benign tumors that infiltrate the muscles.
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Spirito-maron echocardiographic score: a marker for morphological and physiological assessment of patients with hypertrophic cardiomyopathy.
Echocardiography
PUBLISHED: 01-24-2014
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The heterogeneous distribution of hypertrophy in hypertrophic cardiomyopathy (HCM) limits the echocardiographic conventional measurements accuracy in the evaluation of left ventricular hypertrophy (LVH). The aim of this study was to assess the correlation of the echocardiographic Spirito-Maron score (SMS) with left ventricle (LV) mass quantification by cardiac magnetic resonance (CMR) and with LV diastolic function.
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Echocardiographic reference ranges for normal cardiac chamber size: results from the NORRE study.
Eur Heart J Cardiovasc Imaging
PUBLISHED: 01-21-2014
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Availability of normative reference values for cardiac chamber quantitation is a prerequisite for accurate clinical application of echocardiography. In this study, we report normal reference ranges for cardiac chambers size obtained in a large group of healthy volunteers accounting for gender and age. Echocardiographic data were acquired using state-of-the-art cardiac ultrasound equipment following chamber quantitation protocols approved by the European Association of Cardiovascular Imaging.
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Strengthening the perception-assessment tools for dengue prevention: a cross-sectional survey in a temperate region (Madeira, Portugal).
BMC Public Health
PUBLISHED: 01-15-2014
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Community participation is mandatory in the prevention of Dengue outbreaks. Taking public views into account is crucial to guide more effective planning and quicker community participation in preventing campaigns. This study aims to assess community perceptions of Madeira population in order to explore their involvement in the A. aegypti's control and reinforce health-educational planning. Due to the lack of accurate methodologies for measuring perception, a new tool to assess the community's perceptions was built.
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Macroclimate determines the global range limit of Aedes aegypti.
Ecohealth
PUBLISHED: 01-14-2014
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Aedes aegypti is the main vector of dengue and a number of other diseases worldwide. Because of the domestic nature of this mosquito, the relative importance of macroclimate in shaping its distribution has been a controversial issue. We have captured here the worldwide macroclimatic conditions occupied by A. aegypti in the last century. We assessed the ability of this information to predict the species' observed distribution using supra-continental spatially-uncorrelated data. We further projected the distribution of the colonized climates in the near future (2010-2039) under two climate-change scenarios. Our results indicate that the macroclimate is largely responsible for setting the maximum range limit of A. aegypti worldwide and that in the near future, relatively wide areas beyond this limit will receive macroclimates previously occupied by the species. By comparing our projections, with those from a previous model based strictly on species-climate relationships (i.e., excluding human influence), we also found support for the hypothesis that much of the species' range in temperate and subtropical regions is being sustained by artificial environments. Altogether, these findings suggest that, if the domestic environments commonly exploited by this species are available in the newly suitable areas, its distribution may expand considerably in the near future.
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Conservative management of a prosthetic valve thrombosis--report of a successful case.
Heart Lung Circ
PUBLISHED: 01-13-2014
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Prosthetic valve thrombosis (PVT) refers to the presence of non infective material in valvular apparatus, interfering with its function. It is a potentially fatal complication of valvular replacement surgery. Treatment options include surgery, fibrinolysis and anticoagulation optimisation. The authors present the case of a young man, carrier of an aortic prosthetic mechanical valve, who didn't take his anticoagulant medicine, admitted for an acute obstructive PVT, with evidence of a large thrombotic mass on the aortic valve (> 1cm(2)). The patient refused surgical treatment and eventually presented a complete resolution of the acute PVT with anticoagulation optimisation.
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Phenolic profile of Douro wines and evaluation of their NO scavenging capacity in LPS-stimulated RAW 264.7 macrophages.
Food Chem
PUBLISHED: 01-13-2014
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The phenolic profile of two samples of commercial Douro red wines, a table red wine (RM) and a Port wine (PR), was analysed by HPLC-DAD after purification by solid phase extraction (SPE). Eighteen phenolic compounds belonging to benzoic acids, hydroxycinnamic acids and anthocyanins were determined. The presence of tannins in both wines and of polymeric anthocyanins in Port wine could be inferred by the chromatograms registered at 280 and 500 nm, respectively. The wine extracts showed capacity to scavenge sodium nitroprusside-released nitric oxide (NO), RM being more effective than PR, which can be partly attributed to its higher content in monomeric anthocyanins. Using a model of macrophages (RAW 264.7 cells) stimulated with bacterial lipopolysaccharide (LPS) the samples showed a similar potential, which may indicate the importance of polymeric anthocyanins and the higher amount of phenolic acids present in PR to decrease cells NO levels.
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Modulation of basophils' degranulation and allergy-related enzymes by monomeric and dimeric naphthoquinones.
PLoS ONE
PUBLISHED: 01-01-2014
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Allergic disorders are characterized by an abnormal immune response towards non-infectious substances, being associated with life quality reduction and potential life-threatening reactions. The increasing prevalence of allergic disorders demands for new and effective anti-allergic treatments. Here we test the anti-allergic potential of monomeric (juglone, menadione, naphthazarin, plumbagin) and dimeric (diospyrin and diosquinone) naphthoquinones. Inhibition of RBL-2H3 rat basophils' degranulation by naphthoquinones was assessed using two complementary stimuli: IgE/antigen and calcium ionophore A23187. Additionally, we tested for the inhibition of leukotrienes production in IgE/antigen-stimulated cells, and studied hyaluronidase and lipoxidase inhibition by naphthoquinones in cell-free assays. Naphthazarin (0.1 µM) decreased degranulation induced by IgE/antigen but not A23187, suggesting a mechanism upstream of the calcium increase, unlike diospyrin (10 µM) that reduced degranulation in A23187-stimulated cells. Naphthoquinones were weak hyaluronidase inhibitors, but all inhibited soybean lipoxidase with the most lipophilic diospyrin, diosquinone and menadione being the most potent, thus suggesting a mechanism of competition with natural lipophilic substrates. Menadione was the only naphthoquinone reducing leukotriene C4 production, with a maximal effect at 5 µM. This work expands the current knowledge on the biological properties of naphthoquinones, highlighting naphthazarin, diospyrin and menadione as potential lead compounds for structural modification in the process of improving and developing novel anti-allergic drugs.
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Neuroprotective effect of steroidal alkaloids on glutamate-induced toxicity by preserving mitochondrial membrane potential and reducing oxidative stress.
J. Steroid Biochem. Mol. Biol.
PUBLISHED: 10-05-2013
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Several evidences suggest that enhanced oxidative stress is involved in the pathogenesis and/or progression of several neurodegenerative diseases. The aim of this study was to investigate for the first time whether both extracts from tomato plant (Lycopersicon esculentum Mill.) leaves and their isolated steroidal alkaloids (tomatine and tomatidine) afford neuroprotective effect against glutamate-induced toxicity in SH-SY5Y neuroblastoma cells and to elucidate the mechanisms underlying this protection. Steroidal alkaloids from tomato are well known for their cholinesterases inhibitory capacity and the results showed that both purified extracts and isolated compounds, at non-toxic concentrations for gastric (AGS), intestinal (Caco-2) and neuronal (SH-SY5Y) cells, have the capacity to preserve mitochondria membrane potential and to decrease reactive oxygen species levels of SH-SY5Y glutamate-insulted cells. Moreover, the use of specific antagonists of cholinergic receptors allowed observing that tomatine and tomatidine can interact with nicotinic receptors, specifically with the ?7 type. No effect on muscarinic receptors was noticed. In addition to the selective cholinesterases inhibition revealed by the compounds/extracts, these results provide novel and important insights into their neuroprotective mechanism. This work also demystifies the applicability of these compounds in therapeutics, by demonstrating that their toxicity was overestimated for long time.
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Inhibitory signalling to the Arp2/3 complex steers cell migration.
Nature
PUBLISHED: 08-28-2013
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Cell migration requires the generation of branched actin networks that power the protrusion of the plasma membrane in lamellipodia. The actin-related proteins 2 and 3 (Arp2/3) complex is the molecular machine that nucleates these branched actin networks. This machine is activated at the leading edge of migrating cells by Wiskott-Aldrich syndrome protein (WASP)-family verprolin-homologous protein (WAVE, also known as SCAR). The WAVE complex is itself directly activated by the small GTPase Rac, which induces lamellipodia. However, how cells regulate the directionality of migration is poorly understood. Here we identify a new protein, Arpin, that inhibits the Arp2/3 complex in vitro, and show that Rac signalling recruits and activates Arpin at the lamellipodial tip, like WAVE. Consistently, after depletion of the inhibitory Arpin, lamellipodia protrude faster and cells migrate faster. A major role of this inhibitory circuit, however, is to control directional persistence of migration. Indeed, Arpin depletion in both mammalian cells and Dictyostelium discoideum amoeba resulted in straighter trajectories, whereas Arpin microinjection in fish keratocytes, one of the most persistent systems of cell migration, induced these cells to turn. The coexistence of the Rac-Arpin-Arp2/3 inhibitory circuit with the Rac-WAVE-Arp2/3 activatory circuit can account for this conserved role of Arpin in steering cell migration.
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Glutathione and the antioxidant potential of binary mixtures with flavonoids: synergisms and antagonisms.
Molecules
PUBLISHED: 06-05-2013
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Polyphenols are able to trap free radicals, which contributes to their known antioxidant capacity. In plant extracts, these secondary metabolites may act in concert, in a way that their combined activities will be superior to their individual effects (synergistic interaction). Several polyphenols have demonstrated clear antioxidant properties in vitro, and many of their biological actions have been attributed to their intrinsic reducing capabilities. As so, the intake of these compounds at certain concentrations in the diet and/or supplementation may potentiate the activity of reduced form glutathione (GSH), thus better fighting oxidative stress. The aim of this work was to predict a structure-antioxidant activity relationship using different classes of flavonoids and to assess, for the first time, possible synergisms and antagonisms with GSH. For these purposes a screening microassay involving the scavenging of DPPH• was applied. In general, among the tested compounds, those lacking the catechol group in B ring showed antagonistic behaviour with GSH. Myricetin displayed additive effect, while quercetin, fisetin, luteolin, luteolin-7-O-glucoside, taxifolin and (+)-catechin demonstrated synergistic actions. Furthermore, adducts formed at C2 and C5 of the B ring seem to be more important for the antioxidant capacity than adducts formed at C6 and C8 of the A ring.
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Short-time variation in serum uric acid concentrations in post-myocardial infarction patients.
Clin. Lab.
PUBLISHED: 06-04-2013
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Studies on SUA temporal profile in relation to acute myocardial infarction (AMI) are controversial. The aim of this study was to evaluate the SUA level variations following myocardial infarction.
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Integrated analysis of COX-2 and iNOS derived inflammatory mediators in LPS-stimulated RAW macrophages pre-exposed to Echium plantagineum L. bee pollen extract.
PLoS ONE
PUBLISHED: 02-12-2013
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Oxidative stress and inflammation play important roles in disease development. This study intended to evaluate the anti-inflammatory and antioxidant potential of Echium plantagineum L. bee pollen to support its claimed health beneficial effects. The hydromethanol extract efficiently scavenged nitric oxide ((•)NO) although against superoxide (O2(•-)) it behaved as antioxidant at lower concentrations and as pro-oxidant at higher concentrations. The anti-inflammatory potential was evaluated in LPS-stimulated macrophages. The levels of (•)NO and L-citrulline decreased for all extract concentrations tested, while the levels of prostaglandins, their metabolites and isoprostanes, evaluated by UPLC-MS, decreased with low extract concentrations. So, E. plantagineum bee pollen extract can exert anti-inflammatory activity by reducing (•)NO and prostaglandins. The extract is able to scavenge the reactive species (•)NO and O2(•-) and reduce markers of oxidative stress in cells at low concentrations.
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HIV/aids care according to the perspective of healthcare providers.
Rev Esc Enferm USP
PUBLISHED: 01-18-2013
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The present study aimed to understand the care provided to patients with HIV/AIDS in Portugal according to the healthcare providers perspective. Thompsons method of oral history was used in the study, which included 22 healthcare providers. The data were collected by means of semi-structured interviews and were analyzed from the narrative compilation perspective formulated by the author using QSR Nvivo software. The study complied with the ethical precepts for research. Care was analyzed according to three dimensions: cognitive, affective-relational, and technical-instrumental. The participants attributed particular relevance to the cognitive dimension in association with the moment when the diagnosis of HIV/AIDS was established, as well as throughout the course of disease. The affective-relational dimension was cross-sectional and considered to be valuable throughout the course of the disease from its diagnosis to the death of the patients with HIV/AIDS. The technical-instrumental dimension was more expressive in the advanced stages of the disease, in patients suffering from addiction and in terminal illness. As a function of the results, we can conclude that the three investigated dimensions are highly relevant for the care of patients with HIV/AIDS.
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Endosomal recruitment of the WASH complex: active sequences and mutations impairing interaction with the retromer.
Biol. Cell
PUBLISHED: 01-11-2013
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The Wiskott-Aldrich syndrome protein and scar homolog (WASH) complex is the major Arp2/3 activator at the surface of endosomes. The branched actin network, that the WASH complex induces, contributes to cargo sorting and scission of transport intermediates destined for most endosomal routes. A major challenge is to understand how the WASH molecular machine is recruited to the surface of endosomes. The retromer endosomal machinery has been proposed by us and others to play a role in this process.
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Feeding patterns of molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in a region of high hybridization.
Parasit Vectors
PUBLISHED: 01-09-2013
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Two biological forms of the mosquito Culex pipiens s.s., denoted pipiens and molestus, display behavioural differences that may affect their role as vectors of arboviruses. In this study, the feeding patterns of molestus and pipiens forms were investigated in Comporta (Portugal), where high levels of inter-form admixture have been recorded.
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Valproic acid-induced hyperammonemic encephalopathy - a potentially fatal adverse drug reaction.
Springerplus
PUBLISHED: 01-07-2013
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A patient with an early diagnosed epilepsy Valproic acid is one of the most widely used antiepileptic drugs. Hyperammonemic encephalopathy is a rare, but potentially fatal, adverse drug reaction to valproic acid.
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Anopheles atroparvus density modeling using MODIS NDVI in a former malarious area in Portugal.
J. Vector Ecol.
PUBLISHED: 12-02-2011
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Malaria is dependent on environmental factors and considered as potentially re-emerging in temperate regions. Remote sensing data have been used successfully for monitoring environmental conditions that influence the patterns of such arthropod vector-borne diseases. Anopheles atroparvus density data were collected from 2002 to 2005, on a bimonthly basis, at three sites in a former malarial area in Southern Portugal. The development of the Remote Vector Model (RVM) was based upon two main variables: temperature and the Normalized Differential Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra satellite. Temperature influences the mosquito life cycle and affects its intra-annual prevalence, and MODIS NDVI was used as a proxy for suitable habitat conditions. Mosquito data were used for calibration and validation of the model. For areas with high mosquito density, the model validation demonstrated a Pearson correlation of 0.68 (p<0.05) and a modelling efficiency/Nash-Sutcliffe of 0.44 representing the models ability to predict intra- and inter-annual vector density trends. RVM estimates the density of the former malarial vector An. atroparvus as a function of temperature and of MODIS NDVI. RVM is a satellite data-based assimilation algorithm that uses temperature fields to predict the intra- and inter-annual densities of this mosquito species using MODIS NDVI. RVM is a relevant tool for vector density estimation, contributing to the risk assessment of transmission of mosquito-borne diseases and can be part of the early warning system and contingency plans providing support to the decision making process of relevant authorities.
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[Hypocalcemia as a reversible cause of heart failure].
Rev Port Cardiol
PUBLISHED: 09-30-2011
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Calcium plays a key role in heart muscle contraction and relaxation. Hypocalcemic heart failure is a rare and potentially reversible disturbance, which reflects this intrinsic relationship. The authors present the case of a 35-year-old woman who developed acute heart failure during the early postoperative period following total thyroidectomy. The echocardiogram showed severe global left ventricular dysfunction. Laboratory tests showed severe hypocalcemia and new-onset hypoparathyroidism. Cardiac catheterization showed angiographically normal coronary arteries. After clinical, hemodynamic and metabolic stabilization, a repeat echocardiogram revealed recovery of left ventricular function. Subsequently, cardiac magnetic resonance imaging was performed, which also showed no alterations. The patient was discharged asymptomatic, medicated with calcium carbonate, calcitriol and levothyroxine. This case highlights the importance of considering hypocalcemia as a cause of reversible myocardial dysfunction.
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Antibacterial and modulatory effect of Stryphnodendron rotundifolium.
Pharm Biol
PUBLISHED: 08-16-2011
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Stryphnodendron rotundifolium Mart. (Leguminosae), a tree in Northeast Brazil (Chapada do Araripe), is used in popular medicine to treat different processes such as inflammation and infectious diseases, mainly caused by bacterial pathogens.
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Clinical and Laboratorial Features That May Differentiate 46,XY DSD due to Partial Androgen Insensitivity and 5?-Reductase Type 2 Deficiency.
Int J Endocrinol
PUBLISHED: 07-31-2011
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The aim of this study was to search for clinical and laboratorial data in 46,XY patients with ambiguous genitalia (AG) and normal testosterone (T) synthesis that could help to distinguish partial androgen insensitivity syndrome (PAIS) from 5?-reductase type 2 deficiency (5?-RD2) and from cases without molecular defects in the AR and SRD5A2 genes. Fifty-eight patients (51 families) were included. Age at first evaluation, weight and height at birth, consanguinity, familial recurrence, severity of AG, penile length, LH, FSH, T, dihydrotestosterone (DHT), ?4-androstenedione (?4), and T/DHT and T/?4 ratios were evaluated. The AR and SRD5A2 genes were sequenced in all cases. There were 9 cases (7 families) of 5?-RD2, 10 cases (5 families) of PAIS, and 39 patients had normal molecular analysis of SRD5A2 and AR genes. Age at first evaluation, birth weight and height, and T/DHT ratio were lower in the undetermined group, while penile length was higher in this group. Consanguinity was more frequent and severity of AG was higher in 5?-RD2 patients. Familial recurrence was more frequent in PAIS patients. Birth weight and height, consanguinity, familial recurrence, severity of AG, penile length, and T/DHT ratio may help the investigation of 46,XY patients with AG and normal T synthesis.
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Is nitric oxide decrease observed with naphthoquinones in LPS stimulated RAW 264.7 macrophages a beneficial property?
PLoS ONE
PUBLISHED: 04-19-2011
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The search of new anti-inflammatory drugs has been a current preoccupation, due to the need of effective drugs, with less adverse reactions than those used nowadays. Several naphthoquinones (plumbagin, naphthazarin, juglone, menadione, diosquinone and 1,4-naphthoquinone), plus p-hydroquinone and p-benzoquinone were evaluated for their ability to cause a reduction of nitric oxide (NO) production, when RAW 264.7 macrophages were stimulated with lipopolysaccharide (LPS). Dexamethasone was used as positive control. Among the tested compounds, diosquinone was the only one that caused a NO reduction with statistical importance and without cytotoxicity: an IC(25) of 1.09±0.24 µM was found, with 38.25±6.50% (p<0.001) NO reduction at 1.5 µM. In order to elucidate if this NO decrease resulted from the interference of diosquinone with cellular defence mechanisms against LPS or to its conversion into peroxynitrite, by reaction with superoxide radical formed by naphthoquinones redox cycling, 3-nitrotyrosine and superoxide determination was also performed. None of these parameters showed significant changes relative to control. Furthermore, diosquinone caused a decrease in the pro-inflammatory cytokines: tumour necrosis factor-alpha (TNF-?) and interleukin 6 (IL-6). Therefore, according to the results obtained, diosquinone, studied for its anti-inflammatory potential for the first time herein, has beneficial effects in inflammation control. This study enlightens the mechanisms of action of naphthoquinones in inflammatory models, by checking for the first time the contribution of oxidative stress generated by naphthoquinones to NO reduction.
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Evaluation of the Antimicrobial Activity of the Decoction of Tropidurus hispidus (Spix, 1825) and Tropidurus semitaeniatus (Spix, 1825) Used by the Traditional Medicine.
Evid Based Complement Alternat Med
PUBLISHED: 04-01-2011
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Tropidurus hispidus and Tropidurus semitaeniatus are two lizard species utilized in traditional medicine in Northeast Brazil. Their medicinal use includes diseases related with bacterial infections such as tonsillitis and pharyngitis. They are used in the form of teas (decoctions) for the treatment of illnesses. In this work, we evaluated the antimicrobial activity of the decoctions of T. hispidus (DTH) and T. semitaeniatus (DTS) against bacterial strains, namely, standard and multiresistant Escherichia coli, Staphylococus aureus, and Pseudomonas aureuginosa, alone and in combination with aminoglycoside antibiotics. The decoctions were prepared using the whole body of the dried lizards, and the filtrate was frozen and lyophilized. When tested alone, the samples did not demonstrate any substantial inhibition of bacterial growth. However, in combination with antibiotics as aminoglycosides, decoctions reduced the minimal inhibitory concentration (MIC) of the assayed antibiotics against multiresistant strains of S. aureus and P. aureuginosa. Chemical prospecting tests revealed the presence of alkaloids in DTS. This is the first study evaluating the medicinal efficacy of T. hispidus and T. semitaeniatus and contributes to the list of new sources of medicines from natural products of animal origin.
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Genetic and phenotypic variation of the malaria vector Anopheles atroparvus in southern Europe.
Malar. J.
PUBLISHED: 01-11-2011
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There is a growing concern that global climate change will affect the potential for pathogen transmission by insect species that are vectors of human diseases. One of these species is the former European malaria vector, Anopheles atroparvus. Levels of population differentiation of An. atroparvus from southern Europe were characterized as a first attempt to elucidate patterns of population structure of this former malaria vector. Results are discussed in light of a hypothetical situation of re-establishment of malaria transmission.
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Mosquito fauna on the Cape Verde Islands (West Africa): an update on species distribution and a new finding.
J. Vector Ecol.
PUBLISHED: 12-24-2010
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To evaluate the risk of transmission of vector-borne diseases, regular updates of the geographic distribution of insect vectors are required. In the archipelago of Cape Verde, nine mosquito species have been reported. Of these, four are major vectors of diseases that have been present in the archipelago: yellow fever, lymphatic filariasis, malaria and, currently, an outbreak of dengue. In order to assess variation in mosquito biodiversity, we have carried out an update on the distribution of the mosquito species in Cape Verde, based on an enquiry of 26 unpublished technical reports (1983-2006) and on the results of an entomological survey carried out in 2007. Overall, there seems to be a general trend for an expansion of biological diversity in the islands. Mosquito species richness was negatively correlated with the distance of the islands from the mainland but not with the size of the islands. Human- and/or sporadic climatic-mediated events of dispersal may have contributed to a homogenization of species richness regardless of island size but other ecological factors may also have affected the mosquito biogeography in the archipelago. An additional species, Culex perexiguus, was collected for the first time in the archipelago during the 2007 survey.
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Mosquito surveys and West Nile virus screening in two different areas of southern Portugal, 2004-2007.
Vector Borne Zoonotic Dis.
PUBLISHED: 09-22-2010
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Longitudinal mosquito surveys were carried out in southern Portugal from 2004 to 2007, in a wetland area (Comporta, District of Setúbal) and around the perimeter of a dam irrigation plant that created the largest artificial lake in Europe, 250 km(2) (Alqueva, Districts of Evora and Beja). Our aim was to study the diversity, abundance, and seasonal dynamics of mosquitoes, comparing these two different areas, to screen mosquitoes for West Nile Virus (WNV), an arboviral agent already detected in Portugal, because these areas are populated with abundant avian fauna. Monthly collections of adult mosquitoes were carried out by Centers for Disease Control light-traps with CO(2) and by indoor resting collections. Mosquitoes were identified and screened for arboviruses by reverse transcriptase (RT)-polymerase chain reaction directed toward amplification of a 217-bp fragment of the NS5 gene. Mosquito peak densities were observed in July-August in Comporta and May-June, with a plateau in July-October, in Alqueva. However, densities were far higher in Comporta area (220,821 specimens) than in Alqueva area (9442 specimens), with a clear difference in species distribution, as in Comporta the predominant species was Culex theileri (85%), followed by Aedes caspius (6%), Anopheles atroparvus (4%), and Culex pipiens sensu latu (s.l.) (3%), whereas in Alqueva the predominant species was Cx. pipiens s.l. (56%), followed by An. atroparvus (18%), Cx. theileri (14%), and Culiseta longiareolata (9%). Female mosquitoes (8842 in 175 pools) of the species Ae. caspius, An. atroparvus, Culex mimeticus, Cx. pipiens Sensu latu (s.l.), Cx. theileri, and Culex univittatus were screened and found to be negative for WNV genomic RNA. Although there was no detection of WNV sequences in mosquitoes, vigilance should continue as the circulation of virus has been previously detected more than once in Portugal, in humans, animals, and mosquitoes, and in other surrounding Mediterranean countries.
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Mitochondrial redox metabolism in trypanosomatids is independent of tryparedoxin activity.
PLoS ONE
PUBLISHED: 06-22-2010
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Tryparedoxins (TXNs) are oxidoreductases unique to trypanosomatids (including Leishmania and Trypanosoma parasites) that transfer reducing equivalents from trypanothione, the major thiol in these organisms, to sulfur-dependent peroxidases and other dithiol proteins. The existence of a TXN within the mitochondrion of trypanosomatids, capable of driving crucial redox pathways, is considered a requisite for normal parasite metabolism. Here this concept is shown not to apply to Leishmania. First, removal of the Leishmania infantum mitochondrial TXN (LiTXN2) by gene-targeting, had no significant effect on parasite survival, even in the context of an animal infection. Second, evidence is presented that no other TXN is capable of replacing LiTXN2. In fact, although a candidate substitute for LiTXN2 (LiTXN3) was found in the genome of L. infantum, this was shown in biochemical assays to be poorly reduced by trypanothione and to be unable to reduce sulfur-containing peroxidases. Definitive conclusion that LiTXN3 cannot directly reduce proteins located within inner mitochondrial compartments was provided by analysis of its subcellular localization and membrane topology, which revealed that LiTXN3 is a tail-anchored (TA) mitochondrial outer membrane protein presenting, as characteristic of TA proteins, its N-terminal end (containing the redox-active domain) exposed to the cytosol. This manuscript further proposes the separation of trypanosomatid TXN sequences into two classes and this is supported by phylogenetic analysis: i) class I, encoding active TXNs, and ii) class II, coding for TA proteins unlikely to function as TXNs. Trypanosoma possess only two TXNs, one belonging to class I (which is cytosolic) and the other to class II. Thus, as demonstrated for Leishmania, the mitochondrial redox metabolism in Trypanosoma may also be independent of TXN activity. The major implication of these findings is that mitochondrial functions previously thought to depend on the provision of electrons by a TXN enzyme must proceed differently.
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Predicting reduced TLC in patients with low FVC and a normal or elevated FEV1/FVC ratio.
J Bras Pneumol
PUBLISHED: 02-11-2010
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To use clinical and spirometry findings in order to distinguish between the restrictive and nonspecific patterns of pulmonary function test results in patients with low FVC and a normal or elevated FEV1/FVC ratio.
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Knowledge and attitude: important components in diabetes education.
Rev Lat Am Enfermagem
PUBLISHED: 10-13-2009
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This descriptive cross-sectional study was conducted from March to November 2007 at a research and community services center of a Brazilian university. It aimed to explore the knowledge and attitude of people with diabetes mellitus who were attending a diabetes self-care education program. The sample was composed of 82 adults with diabetes mellitus. Data were collected through the Portuguese versions of the Diabetes Knowledge Questionnaire (DKN-A) and the Diabetes Attitude Questionnaire (ATT-19). Results revealed that 78.05% of the participants obtained scores higher than eight on knowledge about diabetes, which indicates they have knowledge and understand the disease. Scores on attitude ranged from 25 to 71 suggesting difficulty in coping with the disease. We conclude that although participants obtained a good score on knowledge, their attitude did not change so as to more adequately cope with the disease.
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Metabolic and bioactivity insights into Brassica oleracea var. acephala.
J. Agric. Food Chem.
PUBLISHED: 09-03-2009
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Seeds of Brassica oleracea var. acephala (kale) were analyzed by HPLC/UV-PAD/MSn-ESI. Several phenolic acids and flavonol derivatives were identified. The seeds of this B. oleracea variety exhibited more flavonol derivatives than those of tronchuda cabbage (Brassica oleracea var. costata), also characterized in this paper. Quercetin and isorhamnetin derivatives were found only in kale seeds. Oxalic, aconitic, citric, pyruvic, malic, quinic, shikimic, and fumaric acids were the organic acids present in these matrices, malic acid being predominant in kale and citric acid in tronchuda cabbage seeds. Acetylcholinesterase (AChE) inhibitory activity was determined in aqueous extracts from both seeds. Kale leaves and butterflies, larvae, and excrements of Pieris brassicae reared on kale were also evaluated. Kale seeds were the most effective AChE inhibitor, followed by tronchuda cabbage seeds and kale leaves. With regard to P. brassicae material, excrements exhibited stronger inhibitory capacity. These results may be explained by the presence of sinapine, an analogue of acetylcholine, only in seed materials. A strong concentration-dependent antioxidant capacity against DPPH, nitric oxide, and superoxide radicals was observed for kale seeds.
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Asymmetric introgression between sympatric molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in the Comporta region, Portugal.
BMC Evol. Biol.
PUBLISHED: 07-09-2009
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Culex pipiens L. is the most widespread mosquito vector in temperate regions. This species consists of two forms, denoted molestus and pipiens, that exhibit important behavioural and physiological differences. The evolutionary relationships and taxonomic status of these forms remain unclear. In northern European latitudes molestus and pipiens populations occupy different habitats (underground vs. aboveground), a separation that most likely promotes genetic isolation between forms. However, the same does not hold in southern Europe where both forms occur aboveground in sympatry. In these southern habitats, the extent of hybridisation and its impact on the extent of genetic divergence between forms under sympatric conditions has not been clarified. For this purpose, we have used phenotypic and genetic data to characterise Cx. pipiens collected aboveground in Portugal. Our aims were to determine levels of genetic differentiation and the degree of hybridisation between forms occurring in sympatry, and to relate these with both evolutionary and epidemiological tenets of this biological group.
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Volatile composition of Brassica oleracea L. var. costata DC leaves using solid-phase microextraction and gas chromatography/ion trap mass spectrometry.
Rapid Commun. Mass Spectrom.
PUBLISHED: 07-07-2009
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Volatile and semi-volatile components of internal and external leaves of Brassica oleracea L. var. costata DC, grown under different fertilization regimens, were determined by headspace solid-phase microextraction (HS-SPME) combined with gas chromatography/ion trap mass spectrometry (GC/ITMS). Forty-one volatiles and non-volatile components were formally identified and thirty others were tentatively identified. Qualitative and quantitative differences were noticed between internal and external leaves. In general, internal leaves exhibited more aldehydes and sulfur volatile compounds than external ones, and less ketone, terpenes and norisoprenoid compounds. The fertilization regimens influenced considerably the volatile profile. Fertilizations with higher levels of sulfur produced Brassica leaves with more sulfur volatiles. In opposition, N and S fertilization led to leaves with lower levels of norisoprenoids and terpenes.
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Present habitat suitability for Anopheles atroparvus (Diptera, Culicidae) and its coincidence with former malaria areas in mainland Portugal.
Geospat Health
PUBLISHED: 05-15-2009
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Malaria was a major health problem in the first half of the 20th Century in mainland Portugal. Nowadays, although the disease is no longer endemic, there is still the risk of future endemic infections due to the continuous occurrence of imported cases and the possibility of transmission in the country by Anopheles atroparvus Van Thiel, 1927. Since vector abundance constitute one of the foremost factors in malaria transmission, we have created several habitat suitability models to describe this vector species current distribution. Three different correlative models; namely (i) a multilayer perceptron artificial neural network (MLP-ANN); (ii) binary logistic regression (BLR); and (iii) Mahalanobis distance were used to combine the species records with a set of five environmental predictors. Kappa coefficient values from k-fold cross-validation records showed that binary logistic regression produced the best predictions, while the other two models also produced acceptable results. Therefore, in order to reduce uncertainty, the three suitability models were combined. The resulting model identified high suitability for An. atroparvus in the majority of the country with exception of the northern and central coastal areas. Malaria distribution during the last endemic period in the country was also compared with the combined suitability model, and a high degree of spatial agreement was obtained (kappa = 0.62). It was concluded that habitat suitability for malaria vectors can constitute valuable information on the assessment of several spatial attributes of the disease. In addition, the results suggest that the spatial distribution of An. atroparvus in the country remains very similar to the one known about seven decades ago.
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[Chylothorax - case report].
Rev Port Pneumol
PUBLISHED: 04-30-2009
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Chylothorax is the occurrence of lymph in the pleura due to damage or obstruction of the thoracic duct. High content of triglycerides and the presence of chylomicrons make the diagnosis of chylothorax. Its aetiology can be divided in traumatic and non-traumatic. Traumatic rupture occurs after accidents or surgery. Within non-traumatic aetiology, lymphoma is the most common and in the presence of a chylothorax of unknown origin this should be the first suspicion, being non-Hodgkin type the most frequent. The authors present a case report of a patient with chylothorax due to non-Hodgkin lymphoma, discuss the particularities of chylothorax as well as the investigation and its treatment options.
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Screening of antioxidant phenolic compounds produced by in vitro shoots of Brassica oleracea L. var. costata DC.
Comb. Chem. High Throughput Screen.
PUBLISHED: 03-12-2009
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The phenolic compounds produced by in vitro shoots of Brassica oleracea L. var. costata DC were screened by HPLC-DAD-MS/MS. Thirty seven compounds were characterized, which included chlorogenic acids, flavonoids (the majority of them were hydroxycinnamic acid esters of kaempferol and quercetin glycosides) and hydroxycinnamic acyl glycosides (with predominance of synapoyl gentiobiosides). The antioxidant capacity of the shoots was assessed against DPPH radical and two reactive oxygen species (superoxide radical and hypochlorous acid). A strong concentration-dependent antioxidative capacity was verified in the DPPH and superoxide radicals assays, but a reduced effect was noticed against hypochlorous acid. The results obtained indicate that the in vitro production of B. oleracea var. costata shoots can become important in the obtention of a noticeable dietary source of compounds with health protective potential.
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Pieris brassicae inhibits xanthine oxidase.
J. Agric. Food Chem.
PUBLISHED: 02-21-2009
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The antioxidant potential of an aqueous extract obtained from Pieris brassicae larvae reared on Brassica oleracea L. var. costata DC was evaluated against 2,2-diphenyl-1-picrylhydrazyl radical and several reactive oxygen species. The results revealed an effective concentration-dependent protective activity against superoxide and hydroxyl radicals, being superior to that of the host plant. In addition, the larvae extract also exhibited a strong inhibitory effect on xanthine oxidase that was not observed for B. oleracea var. costata. A weak scavenging ability was noticed for hypochlorous acid. Several phenolic compounds with complex chemical structures that are hard to synthesize in the laboratory were found in P. brassicae extract. This is the first time that an insect has been tested for its xanthine oxidase inhibitory capacity, which proved to be very high. These findings are interesting considering that they can be used by food or pharmaceutical industries to prevent the oxidation of their products, to increase the dietary supply of antioxidants, or for prevention of free radical-mediated diseases, namely, gout.
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Galantamine protects against oxidative stress induced by amyloid-beta peptide in cortical neurons.
Eur. J. Neurosci.
PUBLISHED: 02-19-2009
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Galantamine is currently used in the treatment of patients with mild-to-moderate Alzheimers disease (AD). Although its action is mostly directed at the regulation of cholinergic transmission, galantamine can also afford neuroprotection against amyloid-beta peptide (Abeta), which is involved in AD pathogenesis. In this study, we used cultured rat cortical neurons treated with two forms of Abeta(1-40), fresh and previously aged (enriched in fibrils). First, we confirmed that galantamine prevented neurodegeneration induced by both peptide forms in a concentration-dependent manner. Moreover, we observed that when neurons were co-incubated with fresh Abeta(1-40) plus galantamine, the amount of amyloid aggregates was reduced. As oxidative conditions influence Abeta aggregation, we investigated whether galantamine prevents oxidative stress induced by this peptide. The data show that either fresh or aged Abeta(1-40) significantly increased the amount of reactive oxygen species and lipoperoxidation, these effects being prevented by galantamine. In Abeta(1-40)-treated neurons, the depletion of reduced glutathione (GSH) seems to be related to the decrease in glutathione peroxidase and glutathione reductase activities(.) These alterations in the GSH antioxidant system were prevented by galantamine. Overall, these results constitute the first evidence that galantamine can prevent the neuronal oxidative damage induced by Abeta, providing an in vitro basis for the beneficial actions of galantamine in the AD neurodegenerative process.
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In vitro cultures of Brassica oleracea L. var. costata DC: potential plant bioreactor for antioxidant phenolic compounds.
J. Agric. Food Chem.
PUBLISHED: 02-06-2009
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In this work were studied the phenolic composition of in vitro material (shoots, calli, and roots) of Brassica oleracea var. costata and its antioxidant capacity. Samples were obtained in different culture medium, with distinct supplementations to verify their influence on those parameters. Phenolic determination was achieved by HPLC-DAD. Antioxidant activity was assessed against DPPH. In calli and roots no phenolic compound was identified. In shoots was verified the presence of 36 compounds, which included hydroxycinnamic acids, flavonoids (kaempferol and quercetin derivatives), and hydroxycinnamic acyl glycosides (with a predominance of synapoyl gentiobiosides). MS liquid medium supplemented with 2 mg/L benzylaminopurine (BAP) and 0.1 mg/L naphthaleneacetic acid (NAA) revealed to be the best in vitro condition to produce shoot material with highest phenolic compound contents and stronger antioxidant potential, thus with a possible increase of health benefits.
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Novel 3-hydroxy-4-pyridinonato oxidovanadium(IV) complexes to investigate structure/activity relationships.
J. Inorg. Biochem.
PUBLISHED: 01-18-2009
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A previous evaluation of the insulin-like activity of three 3-hydroxy-4-pyridinonato oxidovanadium(IV) complexes raised questions about structure/activity relationships, namely the influence of the hydrophilic/lipophilic balance of the complex and the capacity of the ligand to stabilize the +4 oxidation state of vanadium ion, on achieving an positive effect. To address these questions, we synthesized six new oxidovanadium(IV) complexes with variable hydrophilic/lipophilic balance, obtained by introducing different substituents on the nitrogen atom, and used two 3-hydroxy-4-pyrones as starting reagents to provide methyl and ethyl groups in the ortho position of the ring. For the new and previously reported complexes, we studied the oxidation-reduction properties and insulin-like activity in terms of inhibitory effect on Free fatty acid (FFA) release in isolated rat adipocytes. The results obtained show that only one of the complexes, Bis(3-hydroxy-1(H)-2-methyl-4-pyridonato)oxidovanadium(IV), VO(mpp)(2), exhibits a significantly greater capacity to inhibit FFA release than VOSO(4) and consequently is worthy to be considered for further studies. The establishment of structure activity relationships was not attainable but this study brings new information about the influence of some properties of the compounds on the achievement of an insulin-like effect. The results reveal that: (i) the oxidation-reduction cycles of the complexes are identical; (ii) the presence of more lipophilic substituents on the nitrogen atom does not enhance insulin-like properties; (iii) a high solubility in water proved to be not sufficient for a positive activity in inhibiting FFA release; (iv) a small molecular size may be an important property for reaching the right targets.
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[A thousand total colonoscopies: what is the relationship between distal and proximal findings?].
Acta Med Port
PUBLISHED: 01-16-2009
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Flexible sigmoidoscopy is indicated for colorectal cancer screening. The decision about who needs total colonoscopy based on distal findings is still controversial because of the uncertainty of the associations between distal and proximal findings.
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The Arp2/3 activator WASH controls the fission of endosomes through a large multiprotein complex.
Dev. Cell
PUBLISHED: 01-15-2009
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The Arp2/3 complex generates branched actin networks when activated by Nucleation Promoting Factors (NPFs). Recently, the WASH family of NPFs has been identified, but its cellular role is unclear. Here, we show that WASH generates an actin network on a restricted domain of sorting and recycling endosomes. We found that WASH belongs to a multiprotein complex containing seven subunits, including the heterodimer of capping protein (CP). In vitro, the purified WASH complex activates Arp2/3-mediated actin nucleation and binds directly to liposomes. WASH also interacts with dynamin. WASH depletion gives rise to long membrane tubules pulled out from endosomes along microtubules, as does dynamin inhibition. Accordingly, WASH is required for efficient transferrin recycling. Together, these data suggest that the WASH molecular machine, integrating CP with a NPF, controls the fission of endosomes through an interplay between the forces generated by microtubule motors and actin polymerization.
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The cytosolic tryparedoxin of Leishmania infantum is essential for parasite survival.
Int. J. Parasitol.
PUBLISHED: 01-13-2009
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Leishmania infantum cytosolic tryparedoxin (LiTXN1) can be regarded as a potential candidate for drug targeting. This redox active molecule, which belongs to the thioredoxin superfamily, is one constituent of the hydroperoxide elimination cascade in L. infantum and may also be involved in other cellular processes such as DNA synthesis or host-parasite interaction. In order to validate LiTXN1 as a drug target we have employed a gene replacement strategy. We observed that substitution of both chromosomal LiTXN1 alleles was only possible upon parasite complementation with an episomal copy of the gene. Furthermore, contrary to control parasites carrying the empty vector, both the insect and the mammalian stages of L. infantum retained the episomal copy of LiTXN1 in the absence of drug pressure. These results confirm the essentiality of LiTXN1 throughout the life cycle of the parasite, namely in the disease-causing amastigote stage. In addition, the data obtained showed that disruption of one allele of this gene leads only to a 25% reduction in the expression of LiTXN1. Even though this does not affect promastigote growth and susceptibility to hydrogen peroxide, ex vivo infection assays suggest that wild-type levels of LiTXN1 are required for optimal L. infantum virulence.
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The Culex pipiens complex in continental Portugal: distribution and genetic structure.
J. Am. Mosq. Control Assoc.
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Portugal is a southern European country that displays favorable ecological conditions for the establishment of West Nile virus (WNV) transmission cycles. Competent mosquito vector species are present throughout the country. Among the species with reported cases of WNV isolation in Portugal, Culex pipiens is the most ubiquitous and abundant mosquito. This species exhibits two biological forms with differences in host preferences. The molestus form has a greater tendency to feed upon humans and other mammals whereas the pipiens form prefers avian hosts. In northern latitudes, both forms are physically separated, with molestus occupying underground habitats and pipiens being found aboveground. However, the warmer climatic conditions of southern regions such as Portugal may favor the sympatric occurrence of both forms hence promoting interform hybridization. Genetic introgression between molestus and pipiens forms may result in a higher propensity for admixed populations to serve as bridge-vectors of WNV between humans and birds. Here we revise our present knowledge on the distribution, role in WNV transmission and genetic structure of the Cx. pipiens complex in continental Portugal. We focus on recent findings of sympatric molestus and pipiens populations that display considerable levels of hybridization and discuss the epidemiological repercussions of this occurrence.
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46,XX DSD and Antley-Bixler syndrome due to novel mutations in the cytochrome P450 oxidoreductase gene.
Arq Bras Endocrinol Metabol
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Deficiency of the enzyme P450 oxidoreductase is a rare form of congenital adrenal hyperplasia with characteristics of combined and partial impairments in steroidogenic enzyme activities, as P450 oxidoreductase transfers electrons to CYP21A2, CYP17A1, and CYP19A1. It results in disorders of sex development and skeletal malformations similar to Antley-Bixley syndrome. We report the case of a 9-year-old girl who was born with virilized genitalia (Prader stage V), absence of palpable gonads, 46,XX karyotype, and hypergonadotropic hypogonadism. During the first year of life, ovarian cyst, partial adrenal insufficiency, and osteoarticular changes, such as mild craniosynostosis, carpal and tarsal synostosis, and limited forearm pronosupination were observed. Her mother presented severe virilization during pregnancy. The molecular analysis of P450 oxidoreductase gene revealed compound heterozygosis for the nonsense p.Arg223*, and the novel missense p.Met408Lys, inherited from the father and the mother, respectively.
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Clinical and molecular spectrum of patients with 17?-hydroxysteroid dehydrogenase type 3 (17-?-HSD3) deficiency.
Arq Bras Endocrinol Metabol
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The enzyme 17?-hydroxysteroid dehydrogenase type 3 (17-?-HSD3) catalyzes the conversion of androstenedione to testosterone in the testes, and its deficiency is a rare disorder of sex development in 46,XY individuals. It can lead to a wide range of phenotypic features, with variable hormonal profiles. We report four patients with the 46,XY karyotype and 17-?-HSD3 deficiency, showing different degrees of genital ambiguity, increased androstenedione and decreased testosterone levels, and testosterone to androstenedione ratio < 0.8. In three of the patients, diagnosis was only determined due to the presence of signs of virilization at puberty. All patients had been raised as females, and female gender identity was maintained in all of them. Compound heterozygosis for c.277+2T>G novel mutation, and c.277+4A>T mutation, both located within the intron 3 splice donor site of the HSD17B3 gene, were identified in case 3. In addition, homozygosis for the missense p.Ala203Val, p.Gly289Ser, p.Arg80Gln mutations were found upon HSD17B3 gene sequencing in cases 1, 2, and 4, respectively.
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Phlorotannin extracts from fucales characterized by HPLC-DAD-ESI-MSn: approaches to hyaluronidase inhibitory capacity and antioxidant properties.
Mar Drugs
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Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC?? = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC?? = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC?? = 0.93 mg/mL dry weight), followed by F. spiralis (IC?? = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process.
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An atypical presentation of infective endocarditis.
Rev Port Cardiol
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Infective endocarditis is a well-known clinical entity. However, despite improved diagnostic techniques and advances in treatment options, left-sided native valve infective endocarditis remains a serious disease with high morbidity and mortality, especially in cases caused by Staphylococcus aureus. The clinical heterogeneity of infective endocarditis sometimes prevents rapid recognition, correct diagnosis and timely treatment, which are essential to reduce the morbidity and mortality associated with this disease. We report the case of a 62-year-old man, admitted for atrial fibrillation with complete atrioventricular block, which was found to be the result of methicillin-resistant S. aureus mitral valve endocarditis, complicated by local extension of the infection, heart failure, systemic embolism and multiple organ failure.
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[Metastatic tumor of the right ventricle: an unusual location of tumor involvement in laryngeal carcinoma].
Rev Port Cardiol
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Secondary tumors are much more frequent than primary tumors, but cardiac metastasis of laryngeal carcinoma is uncommon. The authors report the case of a 71-year-old man, with a history of laryngeal carcinoma, admitted to the emergency room with symptoms of two weeks evolution suggestive of respiratory infection. Due to lack of therapeutic response and progressive clinical deterioration, a transthoracic echocardiogram was performed which revealed a large infiltrating mass within the right ventricle, involving the apex, interventricular septum and free wall, not causing significant right ventricular outflow tract obstruction. Evaluation by computed tomography showed signs of widespread metastasis from the previously diagnosed laryngeal cancer.
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Embolic complication of left ventricular non-compaction as an unusual cause of acute myocardial infarction.
Rev Port Cardiol
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One of the greatest challenges in medicine consists of arriving at a correct diagnosis despite different presentations of the disease. We present a case in which, notwithstanding the initial diagnosis, the search for the etiology was essential for clinical guidance. Left ventricular non-compaction (LVNC) was first described by Chin et al. in 1990. This relatively new entity is characterized by excessive thickening of the myocardial wall, formed of a thin epicardial layer and a substantially thicker non-compacted endocardial layer. The clinical presentation is highly variable but it must always be borne in mind that heart failure, atrial and ventricular arrhythmias and embolic events are common complications of LVNC.
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Acute coronary syndrome, right ventricular dysfunction and cardiogenic shock: a diagnostic challenge.
Rev Port Cardiol
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Right ventricular infarction is uncommon in isolation but can be observed in 50% of cases of inferior wall myocardial infarction. Diagnosis is difficult and suspicion of this condition should always be borne in mind. Progression to cardiogenic shock is not uncommon, when the outcome is similar to left ventricular infarction; mortality can reach 60%. We present the case of a 64-year-old woman with known coronary disease who was admitted to our coronary care unit after an anterior myocardial infarction. Cardiac catheterization showed diffuse stenosis of the left descending and 70% stenosis of the posterior descending arteries. She was surgically revascularized with a favorable evolution, but was later readmitted for acute decompensated heart failure with cardiogenic shock. She was refractory to medical therapy, with biventricular dysfunction on echocardiographic examination. Cardiac magnetic resonance imaging confirmed the diagnosis of right ventricular infarction.
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Hybridization and population structure of the Culex pipiens complex in the islands of Macaronesia.
Ecol Evol
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The Culex pipiens complex includes two widespread mosquito vector species, Cx. pipiens and Cx. quinquefasciatus. The distribution of these species varies in latitude, with the former being present in temperate regions and the latter in tropical and subtropical regions. However, their distribution range overlaps in certain areas and interspecific hybridization has been documented. Genetic introgression between these species may have epidemiological repercussions for West Nile virus (WNV) transmission. Bayesian clustering analysis based on multilocus genotypes of 12 microsatellites was used to determine levels of hybridization between these two species in Macaronesian islands, the only contact zone described in West Africa. The distribution of the two species reflects both the islands biogeography and historical aspects of human colonization. Madeira Island displayed a homogenous population of Cx. pipiens, whereas Cape Verde showed a more intriguing scenario with extensive hybridization. In the islands of Brava and Santiago, only Cx. quinquefasciatus was found, while in Fogo and Maio high hybrid rates (?40%) between the two species were detected. Within the admixed populations, second-generation hybrids (?50%) were identified suggesting a lack of isolation mechanisms. The observed levels of hybridization may locally potentiate the transmission to humans of zoonotic arboviruses such as WNV.
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Phytochemical investigations and biological potential screening with cellular and non-cellular models of globe amaranth (Gomphrena globosaL.) inflorescences.
Food Chem
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Gomphrena globosaL. is a popular edible plant used as food colourant and in traditional medicine. In this work, 24 phenolic compounds and eight betacyanins were determined by HPLC-DAD in three different extracts of G. globosa inflorescences. The decoction presented the highest amount of phenolic compounds, kaempferol-3-O-(6-rhamnosyl)hexoside plus kaempferol-3-O-hexoside being the main compounds. The rich betacyanins extract showed isogomphrenin III and gomphrenin III as major metabolites. Decreases in the nitric oxide amounts were observed in LPS-stimulated RAW 264.7 cells. In vitro scavenging micro assays against several reactive species revealed a great antioxidant capacity, particularly against superoxide radical. In general, the best results were obtained with decoction. Some relationships between activity and composition were established. The data provide evidence of the G. globosa inflorescences potential as a source of anti-inflammatory compounds, with relevance for the treatment of acute or chronic inflammatory conditions, and health-promoting antioxidants for use by both food and pharmaceutical industries.
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Highlights of the Brazilian Thoracic Association guidelines for interstitial lung diseases.
J Bras Pneumol
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Interstitial lung diseases (ILDs) are heterogeneous disorders, involving a large number of conditions, the approach to which continues to pose an enormous challenge for pulmonologists. The 2012 Brazilian Thoracic Association ILD Guidelines were established in order to provide Brazilian pulmonologists with an instrument that can facilitate the management of patients with ILDs, standardizing the criteria used for the diagnosis of different conditions and offering guidance on the best treatment in various situations. The objective of this article was to briefly describe the highlights of those guidelines.
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[Cervical length as a predictor of the latent period and infection in preterm premature membranes rupture].
Rev Bras Ginecol Obstet
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To verify cervical length using transvaginal ultrasonography in pregnant women between 28 and 34 weeks of gestation, correlating it with the latent period and the risk of maternal and neonatal infections.
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Brassica oleracea L. Var. costata DC and Pieris brassicae L. aqueous extracts reduce methyl methanesulfonate-induced DNA damage in V79 hamster lung fibroblasts.
J. Agric. Food Chem.
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Brassica oleracea L. var. costata DC leaves and Pieris brassicae L. larvae aqueous extracts were assayed for their potential to prevent/induce DNA damage. None of them was mutagenic at the tested concentrations in the Ames test reversion assay using Salmonella His(+) TA98 strains, with and without metabolic activation. In the hypoxanthine-guanine phosphoribosyltransferase mutation assay using mammalian V79 fibroblast cell line, extracts at 500 ?g/mL neither induced mutations nor protected against the mutagenicity caused by methyl methanesulfonate (MMS). In the comet assay, none of the extracts revealed to be genotoxic by itself, and both afforded protection, more pronounced for larvae extracts, against MMS-induced genotoxicity. As genotoxic/antigenotoxic effects of Brassica vegetables are commonly attributed to isothiocyanates, the extracts were screened for these compounds by headspace-solid-phase microextraction/gas chromatography-mass spectrometry. No sulfur compound was detected. These findings demonstrate that both extracts could be useful against damage caused by genotoxic compounds, the larvae extract being the most promising.
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Kale extract increases glutathione levels in V79 cells, but does not protect them against acute toxicity induced by hydrogen peroxide.
Molecules
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This study aims to evaluate the antioxidant potential of extracts of Brassica oleracea L. var. acephala DC. (kale) and several materials of Pieris brassicae L., a common pest of Brassica cultures using a cellular model with hamster lung fibroblast (V79 cells) under quiescent conditions and subjected to H?O? induced oxidative stress. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and glutathione was determined by the 5,5-dithiobis(2-nitrobenzoic acid) (DTNB)-oxidized glutathione (GSSG) reductase recycling assay. The phenolic composition of the extracts was also established by HPLC-DAD. They presented acylated and non acylated flavonoid glycosides, some of them sulfated, and hydroxycinnamic acyl gentiobiosides. All extracts were cytotoxic by themselves at high concentrations and failed to protect V79 cells against H?O? acute toxicity. No relationship between phenolic composition and cytotoxicity of the extracts was found. Rather, a significant increase in glutathione was observed in cells exposed to kale extract, which contained the highest amount and variety of flavonoids. It can be concluded that although flavonoids-rich extracts have the ability to increase cellular antioxidant defenses, the use of extracts of kale and P. brassicae materials by pharmaceutical or food industries, may constitute an insult to health, especially to debilitated individuals, if high doses are consumed.
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Can phlorotannins purified extracts constitute a novel pharmacological alternative for microbial infections with associated inflammatory conditions?
PLoS ONE
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Bacterial and fungal infections and the emerging multidrug resistance are driving interest in fighting these microorganisms with natural products, which have generally been considered complementary to pharmacological therapies. Phlorotannins are polyphenols restricted to brown seaweeds, recognized for their biological capacity. This study represents the first research on the antibacterial, antifungal, anti-inflammatory and antioxidant activity of phlorotannins purified extracts, which were obtained from ten dominant brown seaweeds of the occidental Portuguese coast.Phlorotannins content was determined by the specific dimethoxybenzaldehyde (DMBA) method and a yield between 75 and 969 mg/Kg phloroglucinol units (dry matter) was obtained. Fucus spiralis ranked first, followed by three Cystoseira species. The anti-inflammatory potential of the purified extracts was assessed via inhibitory effect on nitric oxide (NO) production by lipopolysaccharide-stimulated RAW 264.7 macrophage cells, Cystoseira tamariscifolia being the one showing promising activity for the treatment of inflammation. NO scavenging ability was also addressed in cell free systems, F. spiralis being the species with highest capacity. The antimicrobial potential of the extracts was checked against five Gram-positive and four Gram-negative bacteria and three fungi strains, that commonly colonize skin and mucosa and are responsible for food contamination. The different extracts were more effective against Gram-positive bacteria, Staphylococcus epidermidis being the most susceptible species. Concerning antifungal activity, Trichophyton rubrum was the most sensitive species.Although the molecular mechanisms underlying these properties remain poorly understood, the results obtained turn phlorotannins purified extracts a novel and potent pharmacological alternative for the treatment of a wide range of microbial infections, which usually also present an inflammatory component. In addition to the biological properties demonstrated herein, phlorotannins extracts may also be preferred, in order to avoid side effects and allergic reactions commonly associated with synthetic drugs.
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