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Find video protocols related to scientific articles indexed in Pubmed.
Structural changes of dilated pelvic ureters in adults.
Acta Cir Bras
PUBLISHED: 10-30-2014
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To perform a quantitative assessment of different types of pelvic ureter tissues with chronic dilation in adults, using stereological methods.
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Assessment of IgG antibodies to Pseudomonas aeruginosa in patients with cystic fibrosis by an enzyme-linked immunosorbent assay (ELISA).
Diagn Pathol
PUBLISHED: 08-22-2014
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The usefulness of serological tests for detection of P. aeruginosa pulmonary infection in cystic fibrosis (CF) is controversial. Here, we assessed the value of detecting anti-P. aeruginosa IgG by a quantitative enzyme-linked immunosorbent assay (ELISA) for identification of P. aeruginosa infection in patients with cystic fibrosis.
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Adaptation, Update and Validation of the General Nutrition Questionnaire in a Portuguese Adolescent Sample.
Ecol Food Nutr
PUBLISHED: 08-09-2014
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This article describes the adaptation of the adult Portuguese version of the General Nutrition Knowledge Questionnaire (GNKQ) for adolescents, and its validation. Respondents were 1,315 adolescents, who completed the questionnaire in two phases. A subsample of 73 adolescents was used to measure test-retest reliability. Concurrent validity was tested using a sample of 32 dietetic students. The adapted version showed high internal consistency (Cronbach's alpha = 0.92), test-retest reliability (R = 0.71) and concurrent validity (U = 22766.0; p < .01). Adolescents' nutrition knowledge can now be assessed with a valid and reliable instrument. Future validation works of this or others questionnaires for children and elderly are warranted.
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New less invasive ventricular reconstruction technique in the treatment of ischemic heart failure.
Rev Port Cardiol
PUBLISHED: 08-08-2014
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Ischemic cardiomyopathy is the leading cause of heart failure. In patients with left ventricular (LV) dilatation, low ejection fraction, and transmural scar in an anteroseptal distribution, surgical ventricular reconstruction (SVR) is a treatment option. We describe our first experience with the Less Invasive Ventricular Enhancement (LIVE) technique using the Revivent™ system (Bioventrix Inc., San Ramon, CA), in the treatment of a large anteroapical aneurysm.
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A systems level analysis reveals transcriptomic and proteomic complexity in ixodes ricinus midgut and salivary glands during early attachment and feeding.
Mol. Cell Proteomics
PUBLISHED: 07-21-2014
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Although pathogens are usually transmitted within the first 24-48 h of attachment of the castor bean tick Ixodes ricinus, little is known about the tick's biological responses at these earliest phases of attachment. Tick midgut and salivary glands are the main tissues involved in tick blood feeding and pathogen transmission but the limited genomic information for I. ricinus delays the application of high-throughput methods to study their physiology. We took advantage of the latest advances in the fields of Next Generation RNA-Sequencing and Label-free Quantitative Proteomics to deliver an unprecedented, quantitative description of the gene expression dynamics in the midgut and salivary glands of this disease vector upon attachment to the vertebrate host. A total of 373 of 1510 identified proteins had higher expression in the salivary glands, but only 110 had correspondingly high transcript levels in the same tissue. Furthermore, there was midgut-specific expression of 217 genes at both the transcriptome and proteome level. Tissue-dependent transcript, but not protein, accumulation was revealed for 552 of 885 genes. Moreover, we discovered the enrichment of tick salivary glands in proteins involved in gene transcription and translation, which agrees with the secretory role of this tissue; this finding also agrees with our finding of lower tick t-RNA representation in the salivary glands when compared with the midgut. The midgut, in turn, is enriched in metabolic components and proteins that support its mechanical integrity in order to accommodate and metabolize the ingested blood. Beyond understanding the physiological events that support hematophagy by arthropod ectoparasites, we discovered more than 1500 proteins located at the interface between ticks, the vertebrate host, and the tick-borne pathogens. Thus, our work significantly improves the knowledge of the genetics underlying the transmission lifecycle of this tick species, which is an essential step for developing alternative methods to better control tick-borne diseases.
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[Use of the linkage method to identify the risk factors associated with infant mortality: an integrative review of the literature].
Cien Saude Colet
PUBLISHED: 07-12-2014
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Global concern in relation to child mortality gained visibility with the release of the Millennium Development Goals in 2000 in which the reduction of child mortality is included under goal number four, which proposes to reduce the mortality rate of children under five years by two thirds between 1990 and 2015. Reducing child mortality has been a major priority of social health policies of the Brazilian government. The identification of risk factors associated with infant mortality can assist in the planning of actions to restructure and improve care for pregnant women and newborns in order to reduce child mortality. With this in mind, this study sets out to analyze the use of the linkage method to identify risk factors associated with infant mortality. An integrative review of the literature was conducted for this purpose and eight complete articles published between 2008 and 2013 were analyzed using the following key words: infant mortality, risk factors and information systems. The use of the linkage method proved to be very useful, enabling adequate investigation of the factors most strongly related to child mortality, showing its relevance to the study of public health problems.
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Transcriptome sequencing and developmental regulation of gene expression in Anopheles aquasalis.
PLoS Negl Trop Dis
PUBLISHED: 07-01-2014
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Anopheles aquasalis is a major malaria vector in coastal areas of South and Central America where it breeds preferentially in brackish water. This species is very susceptible to Plasmodium vivax and it has been already incriminated as responsible vector in malaria outbreaks. There has been no high-throughput investigation into the sequencing of An. aquasalis genes, transcripts and proteins despite its epidemiological relevance. Here we describe the sequencing, assembly and annotation of the An. aquasalis transcriptome.
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Secular trends in physical fitness of Mozambican school-aged children and adolescents.
Am. J. Hum. Biol.
PUBLISHED: 06-24-2014
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This study presents information about secular trends in physical fitness (PF) levels among Mozambican youth.
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Proinflammatory cytokines correlate with depression and anxiety in colorectal cancer patients.
Biomed Res Int
PUBLISHED: 06-20-2014
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The objective of this study was to investigate whether serum cytokine levels correlate with depression and anxiety in colorectal cancer (CRC) patients. Twenty patients hospitalized for surgical resection of CRC were included in the study group and twenty healthy volunteers comprised the control group. Depression and anxiety were analyzed using the Hospital Anxiety and Depression Scale (HADS), and serum levels of IL-1?, IL-6, IL-8, IL-10, IL-12, TNF-?, and TGF-? were measured by Cytometric Bead Array. We found that more than half of CRC patients presented clinically significant levels of anxiety or depression, and 65% of them manifested a combination of severe anxiety and depression. CRC patients had increased serum levels of IL-1?, IL-6, IL-8, and TNF-? but lower IL-10 concentrations. Correlation analysis between HADS score and cytokine levels revealed a positive association of anxiety and/or depression with IL-1?, IL-6, IL-8, and TNF-? and a negative correlation with IL-10. These results indicate that circulating proinflammatory cytokines are involved in the pathophysiology of anxiety and depression in CRC patients. A better understanding of the molecular mechanisms involved in these psychological disorders will allow the design of therapeutic interventions that lead to an improved quality of life and overall survival of CRC patients.
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The sialotranscriptome of Amblyomma triste, Amblyomma parvum and Amblyomma cajennense ticks, uncovered by 454-based RNA-seq.
Parasit Vectors
PUBLISHED: 06-11-2014
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Tick salivary constituents antagonize inflammatory, immune and hemostatic host responses, favoring tick blood feeding and the establishment of tick-borne pathogens in hosts during hematophagy. Amblyomma triste, A. cajennense and A. parvum ticks are very important in veterinary and human health because they are vectors of the etiological agents for several diseases. Insights into the tick salivary components involved in blood feeding are essential to understanding vector-pathogen-host interactions, and transcriptional profiling of salivary glands is a powerful tool to do so. Here, we functionally annotated the sialotranscriptomes of these three Amblyomma species, which allowed comparisons between these and other hematophagous arthropod species.
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Examining the utility of thresholds for aerobic fitness related to resting blood pressure and BMI in portuguese children.
Am. J. Hum. Biol.
PUBLISHED: 06-07-2014
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This study examined the utility of the Ruiz et al. cut-points when examining body mass index (BMI) and resting blood pressure in young people.
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Identification and characterization of seminal fluid proteins in the Asian tiger mosquito, Aedes albopictus.
PLoS Negl Trop Dis
PUBLISHED: 06-01-2014
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The Asian tiger mosquito (Aedes albopictus) is an important vector for pathogens that affect human health, including the viruses that cause dengue and Chikungunya fevers. It is also one of the world's fastest-spreading invasive species. For these reasons, it is crucial to identify strategies for controlling the reproduction and spread of this mosquito. During mating, seminal fluid proteins (Sfps) are transferred from male mosquitoes to females, and these Sfps modulate female behavior and physiology in ways that influence reproduction. Despite the importance of Sfps on female reproductive behavior in mosquitoes and other insects, the identity of Sfps in Ae. albopictus has not previously been reported. We used transcriptomics and proteomics to identify 198 Sfps in Ae. albopictus. We discuss possible functions of these Sfps in relation to Ae. albopictus reproduction-related biology. We additionally compare the sequences of these Sfps with proteins (including reported Sfps) in several other species, including Ae. aegypti. While only 72 (36.4%) of Ae. albopictus Sfps have putative orthologs in Ae. aegypti, suggesting low conservation of the complement of Sfps in these species, we find no evidence for an elevated rate of evolution or positive selection in the Sfps that are shared between the two Aedes species, suggesting high sequence conservation of those shared Sfps. Our results provide a foundation for future studies to investigate the roles of individual Sfps on feeding and reproduction in this mosquito. Functional analysis of these Sfps could inform strategies for managing the rate of pathogen transmission by Ae. albopictus.
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Simplagrin, a platelet aggregation inhibitor from Simulium nigrimanum salivary glands specifically binds to the Von Willebrand factor receptor in collagen and inhibits carotid thrombus formation in vivo.
PLoS Negl Trop Dis
PUBLISHED: 06-01-2014
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Among the several challenges faced by bloodsucking arthropods, the vertebrate hemostatic response against blood loss represents an important barrier to efficient blood feeding. Here we report the first inhibitor of collagen-induced platelet aggregation derived from the salivary glands of a black fly (Simulium nigrimanum), named Simplagrin.
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Collagen-binding protein, Aegyptin, regulates probing time and blood feeding success in the dengue vector mosquito, Aedes aegypti.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-28-2014
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Mosquito salivary glands have important roles in blood feeding and pathogen transmission. However, the biological relevance of many salivary components has yet to be determined. Aegyptin, a secreted salivary protein from Aedes aegypti, binds collagen and inhibits platelet aggregation and adhesion. We used a transgenic approach to study the relevance of Aegyptin in mosquito blood feeding. Aedes aegypti manipulated genetically to express gene-specific inverted-repeat RNA sequences exhibited significant reductions in Aegyptin mRNA accumulation (85-87%) and protein levels (>80-fold) in female mosquito salivary glands. Transgenic mosquitoes had longer probing times (78-300 s, P < 0.0001) when feeding on mice compared with controls (15-56 s), feeding success was reduced, and those feeding took smaller blood meals. However, no differences in feeding success or blood meal size were found in membrane feeding experiments using defibrinated human blood. Salivary gland extracts from transgenic mosquitoes failed to inhibit collagen-induced platelet aggregation in vitro. Reductions of Aegyptin did not affect salivary ADP-induced platelet aggregation inhibition or disturb anticlotting activities. Our results demonstrate the relevance of Aegyptin for A. aegypti blood feeding, providing further support for the hypothesis that platelet aggregation inhibition is a vital salivary function in blood feeding arthropods. It has been suggested that the multiple mosquito salivary components mediating platelet aggregation (i.e., Aegyptin, apyrase, D7) represent functional redundancy. Our findings do not support this hypothesis; instead, they indicate that multiple salivary components work synergistically and are necessary to achieve maximum blood feeding efficiency.
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Genome analysis of a major urban malaria vector mosquito, Anopheles stephensi.
Genome Biol.
PUBLISHED: 04-27-2014
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Background Anopheles stephensi is the key vector of malaria throughout the Indian subcontinent and Middle East and an emerging model for molecular and genetic studies of mosquito-parasite interactions. The type form of the species is responsible for the majority of urban malaria transmission across its range.ResultsHere, we report the genome sequence and annotation of the Indian strain of the type form of An. stephensi. The 221 Mb genome assembly represents more than 92% of the entire genome and was produced using a combination of 454, Illumina, and PacBio sequencing. Physical mapping assigned 62% of the genome onto chromosomes, enabling chromosome-based analysis. Comparisons between An. stephensi and An. gambiae reveal that the rate of gene order reshuffling on the X chromosome was three times higher than that on the autosomes. An. stephensi has more heterochromatin in pericentric regions but less repetitive DNA in chromosome arms than An. gambiae. We also identify a number of Y-chromosome contigs and BACs. Interspersed repeats constitute 7.1% of the assembled genome while LTR retrotransposons alone comprise more than 49% of the Y contigs. RNA-seq analyses provide new insights into mosquito innate immunity, development, and sexual dimorphism.ConclusionsThe genome analysis described in this manuscript provides a resource and platform for fundamental and translational research into a major urban malaria vector. Chromosome-based investigations provide unique perspectives on Anopheles chromosome evolution. RNA-seq analysis and studies of immunity genes offer new insights into mosquito biology and mosquito-parasite interactions.
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Auditory event-related potentials in children with benign epilepsy with centro-temporal spikes.
Epilepsy Res.
PUBLISHED: 04-12-2014
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Benign focal epilepsy in childhood with centro-temporal spikes (BECTS) is one of the most common forms of idiopathic epilepsy, with onset from age 3 to 14 years. Although the prognosis for children with BECTS is excellent, some studies have revealed neuropsychological deficits in many domains, including language. Auditory event-related potentials (AERPs) reflect activation of different neuronal populations and are suggested to contribute to the evaluation of auditory discrimination (N1), attention allocation and phonological categorization (N2), and echoic memory (mismatch negativity - MMN). The scarce existing literature about this theme motivated the present study, which aims to investigate and document the existing AERP changes in a group of children with BECTS. AERPs were recorded, during the day, to pure and vocal tones and in a conventional auditory oddball paradigm in five children with BECTS (aged 8-12; mean=10 years; male=5) and in six gender and age-matched controls. Results revealed high amplitude of AERPs for the group of children with BECTS with a slight latency delay more pronounced in fronto-central electrodes. Children with BECTS may have abnormal central auditory processing, reflected by electrophysiological measures such as AERPs. In advance, AERPs seem a good tool to detect and reliably reveal cortical excitability in children with typical BECTS.
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A novel highly divergent protein family identified from a viviparous insect by RNA-seq analysis: a potential target for tsetse fly-specific abortifacients.
PLoS Genet.
PUBLISHED: 04-01-2014
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In tsetse flies, nutrients for intrauterine larval development are synthesized by the modified accessory gland (milk gland) and provided in mother's milk during lactation. Interference with at least two milk proteins has been shown to extend larval development and reduce fecundity. The goal of this study was to perform a comprehensive characterization of tsetse milk proteins using lactation-specific transcriptome/milk proteome analyses and to define functional role(s) for the milk proteins during lactation. Differential analysis of RNA-seq data from lactating and dry (non-lactating) females revealed enrichment of transcripts coding for protein synthesis machinery, lipid metabolism and secretory proteins during lactation. Among the genes induced during lactation were those encoding the previously identified milk proteins (milk gland proteins 1-3, transferrin and acid sphingomyelinase 1) and seven new genes (mgp4-10). The genes encoding mgp2-10 are organized on a 40 kb syntenic block in the tsetse genome, have similar exon-intron arrangements, and share regions of amino acid sequence similarity. Expression of mgp2-10 is female-specific and high during milk secretion. While knockdown of a single mgp failed to reduce fecundity, simultaneous knockdown of multiple variants reduced milk protein levels and lowered fecundity. The genomic localization, gene structure similarities, and functional redundancy of MGP2-10 suggest that they constitute a novel highly divergent protein family. Our data indicates that MGP2-10 function both as the primary amino acid resource for the developing larva and in the maintenance of milk homeostasis, similar to the function of the mammalian casein family of milk proteins. This study underscores the dynamic nature of the lactation cycle and identifies a novel family of lactation-specific proteins, unique to Glossina sp., that are essential to larval development. The specificity of MGP2-10 to tsetse and their critical role during lactation suggests that these proteins may be an excellent target for tsetse-specific population control approaches.
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Characterisation of divergent flavivirus NS3 and NS5 protein sequences detected in Rhipicephalus microplus ticks from Brazil.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 03-15-2014
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Transcripts similar to those that encode the nonstructural (NS) proteins NS3 and NS5 from flaviviruses were found in a salivary gland (SG) complementary DNA (cDNA) library from the cattle tick Rhipicephalus microplus. Tick extracts were cultured with cells to enable the isolation of viruses capable of replicating in cultured invertebrate and vertebrate cells. Deep sequencing of the viral RNA isolated from culture supernatants provided the complete coding sequences for the NS3 and NS5 proteins and their molecular characterisation confirmed similarity with the NS3 and NS5 sequences from other flaviviruses. Despite this similarity, phylogenetic analyses revealed that this potentially novel virus may be a highly divergent member of the genus Flavivirus. Interestingly, we detected the divergent NS3 and NS5 sequences in ticks collected from several dairy farms widely distributed throughout three regions of Brazil. This is the first report of flavivirus-like transcripts in R. microplus ticks. This novel virus is a potential arbovirus because it replicated in arthropod and mammalian cells; furthermore, it was detected in a cDNA library from tick SGs and therefore may be present in tick saliva. It is important to determine whether and by what means this potential virus is transmissible and to monitor the virus as a potential emerging tick-borne zoonotic pathogen.
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SLC23A2-05 (rs4987219) and KRAS-LCS6 (rs61764370) polymorphisms in patients with squamous cell carcinoma of the head and neck.
Oncol Lett
PUBLISHED: 02-26-2014
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Cancer is a genetic disease that is highly influenced by environmental factors. To determine the risk factors of squamous cell carcinoma of the head and neck, two polymorphisms, solute carrier family 23 member 2 (SLC23A2-05 [rs4987219]) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS)-LCS6 (rs61764370), and environmental factors, including smoking and alcohol consumption, were studied in a population. The present study included 165 males diagnosed with squamous cell carcinoma of the head and neck. The control group consisted of 230 healthy male subjects without cancer or a family history of cancer. The SLC23A2-05 and KRAS-LCS6 polymorphisms were analyzed by polymerase chain reaction followed by enzymatic digestion. All patients and healthy subjects were assessed with regard to their smoking habit and alcohol consumption as these are considered to be risk factors for cancer. The statistical analysis was performed using logistic regression, Fisher's exact and ?(2) tests. Additional analyses were performed using the programs, multi-factor dimensionality reduction (MDR; version 2.0) and MDR permutation test (version 0.4.7), which consider all variables as risk factors simultaneously. The results of the present study demonstrate that the SLC23A2-05 and KRAS-LCS6 polymorphisms are not a risk factor for squamous cell carcinoma of the head and neck. In the same samples, the association of alcohol consumption (P<0.001) and smoking habit (P<0.001) with cancer presence was positive when each variable was considered individually. Concerning the environmental factors, a positive association of smoking habit and alcohol consumption with cancer, although not with ethnicity (ratio, 1.0244; testing balance accuracy, 0.8733; P<0.001) was identified using the MDR tool, which analyzed the variables and polymorphism genotypes simultaneously. In conclusion, in the present study, squamous cell carcinoma of the head and neck was highly affected by environmental factors when compared with the affect of SLC23A2-05 and KRAS-LCS6 polymorphisms.
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Polymorphisms in the glutathione pathway modulate cystic fibrosis severity: a cross-sectional study.
BMC Med. Genet.
PUBLISHED: 02-17-2014
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Cystic fibrosis (CF) clinically manifests with various levels of severity, which are thought to be modulated by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR), modifier genes, and the environment. This study verified whether polymorphisms in modifier genes associated with glutathione (GSH) metabolism influence CF severity.
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Predictors of quality of life in Portuguese obese patients: a structural equation modeling application.
J Obes
PUBLISHED: 02-16-2014
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Living with obesity is an experience that may affect multiple aspects of an individual's life. Obesity is considered a relevant public health problem in modern societies. To determine the comparative efficacy of different treatments and to assess their impact on patients' everyday life, it is important to identify factors that are relevant to the quality of life of obese patients. The present study aims to evaluate, in Portuguese obese patients, the simultaneous impact of several psychosocial factors on quality of life. This study also explores the mediating role of stigma in the relationship between positive/negative affect and quality of life. A sample of 215 obese patients selected from the main hospitals in Portugal completed self-report questionnaires to assess sociodemographic, clinical, psychosocial, and quality of life variables. Data were analysed using structural equation modeling. The model fitted the data reasonably well, CFI = 0.9, RMSEA = 0.06. More enthusiastic and more active patients had a better quality of life. Those who reflect lower perception of stigma had a better physical and mental health. Partial mediation effects of stigma between positive affect and mental health and between negative affect and physical health were found. The stigma is pervasive and causes consequences for psychological and physical health.
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CFTR genotype and clinical outcomes of adult patients carried as cystic fibrosis disease.
Gene
PUBLISHED: 02-15-2014
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There are nearly 2000 cystic fibrosis transmembrane regulator (CFTR) mutations that cause cystic fibrosis (CF). These mutations are classified into six classes; on the one hand, the first three classes cause severe disease involvement in early childhood, on the other hand, the Class IV, V and VI mutations cause minor severe disease in the same age. Nowadays, with therapeutic advances in CF management and competence of pediatricians, physicians of adults have to deal with two groups of CF patients: (i) adults diagnosed in childhood with severe mutations and (ii) adults who initiated symptoms in adulthood and with Class IV, V and VI mutations. The aim of this study was to analyze adults from a clinical center, treated as CF disease, screening the CFTR genotype and evaluating the clinical characteristics.
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Comparative analysis of salivary gland transcriptomes of Phlebotomus orientalis sand flies from endemic and non-endemic foci of visceral leishmaniasis.
PLoS Negl Trop Dis
PUBLISHED: 02-01-2014
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In East Africa, Phlebotomus orientalis serves as the main vector of Leishmania donovani, the causative agent of visceral leishmaniasis (VL). Phlebotomus orientalis is present at two distant localities in Ethiopia; Addis Zemen where VL is endemic and Melka Werer where transmission of VL does not occur. To find out whether the difference in epidemiology of VL is due to distant compositions of P. orientalis saliva we established colonies from Addis Zemen and Melka Werer, analyzed and compared the transcriptomes, proteomes and enzymatic activity of the salivary glands.
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Lundep, a sand fly salivary endonuclease increases Leishmania parasite survival in neutrophils and inhibits XIIa contact activation in human plasma.
PLoS Pathog.
PUBLISHED: 02-01-2014
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Neutrophils are the host's first line of defense against infections, and their extracellular traps (NET) were recently shown to kill Leishmania parasites. Here we report a NET-destroying molecule (Lundep) from the salivary glands of Lutzomyia longipalpis. Previous analysis of the sialotranscriptome of Lu. longipalpis showed the potential presence of an endonuclease. Indeed, not only was the cloned cDNA (Lundep) shown to encode a highly active ss- and dsDNAse, but also the same activity was demonstrated to be secreted by salivary glands of female Lu. longipalpis. Lundep hydrolyzes both ss- and dsDNA with little sequence specificity with a calculated DNase activity of 300000 Kunitz units per mg of protein. Disruption of PMA (phorbol 12 myristate 13 acetate)- or parasite-induced NETs by treatment with recombinant Lundep or salivary gland homogenates increases parasite survival in neutrophils. Furthermore, co-injection of recombinant Lundep with metacyclic promastigotes significantly exacerbates Leishmania infection in mice when compared with PBS alone or inactive (mutagenized) Lundep. We hypothesize that Lundep helps the parasite to establish an infection by allowing it to escape from the leishmanicidal activity of NETs early after inoculation. Lundep may also assist blood meal intake by lowering the local viscosity caused by the release of host DNA and as an anticoagulant by inhibiting the intrinsic pathway of coagulation.
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Asthma: Gln27Glu and Arg16Gly polymorphisms of the beta2-adrenergic receptor gene as risk factors.
Allergy Asthma Clin Immunol
PUBLISHED: 01-14-2014
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Asthma is caused by both environmental and genetic factors. The ADRB2 gene, which encodes the beta 2-adrenergic receptor, is one of the most extensively studied genes with respect to asthma prevalence and severity. The Arg16Gly (+46A?>?G) and Gln27Glu (+79C?>?G) polymorphisms in the ADRB2 gene cause changes in the amino acids flanking the receptor ligand site, altering the response to bronchodilators and the risk of asthma through complex pathways. The ADRB2 polymorphisms affect beta-adrenergic bronchodilator action and are a tool to identify at-risk populations.
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Optimism on quality of life in Portuguese chronic patients: moderator/mediator?
Rev Assoc Med Bras
PUBLISHED: 01-13-2014
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optimism is an important variable that has consistently been shown to affect adjustment to quality of life in chronic diseases. This study aims to clarify if dispositional optimism exerts a moderating or a mediating influence on the personality traits-quality of life association, in Portuguese chronic patients.
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Psychosocial factors as predictors of quality of life in chronic Portuguese patients.
Health Qual Life Outcomes
PUBLISHED: 01-09-2014
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Chronic illnesses are diseases of long duration and generally of slow progression. They cause significant quality of life impairment. The aim of this study was to analyse psychosocial predictors of quality of life and of subjective well-being in chronic Portuguese patients.
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Human CD117 (cKit)+ innate lymphoid cells have a discrete transcriptional profile at homeostasis and are expanded during filarial infection.
PLoS ONE
PUBLISHED: 01-01-2014
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Since innate lymphoid cells (ILCs) have been found to play a role in the immune response to helminth parasites in rodents, we sought to determine their role in human helminth infection. By developing multicolor flow cytometry-based methods to identify and enumerate circulating ILCs and their subsets, we were able to identify a subset of cKit+ ILCs defined as Lineage (Lin)-/CD45+/cKit+/CD127+ that were significantly expanded in the filarial-infected individuals (p=0.0473) as were those cKit+ ILCs that produced IL-13. Additionally, the frequency of these cKit+ ILCs correlated with the frequency of IL-17 producing CD4+ T cells (Th17 cells; p=0.025). To investigate the function of cKit+ ILCs, sorted, highly purified human ILCs were subjected to transcriptional profiling by RNAseq and compared to appropriate control cells. These cKit+ ILCs expressed TLRs, a broad range of cytokines/cytokine receptors and MHC Class II molecules suggesting that these ILCs sense pathogens independent of other cell types. Functional analysis revealed expanded cKit+ ILC-specific transcription and ILC-specific microRNA precursors.
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Evidence for a lectin specific for sulfated glycans in the salivary gland of the malaria vector, Anopheles gambiae.
PLoS ONE
PUBLISHED: 01-01-2014
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Salivary gland homogenate (SGH) from the female mosquitoes Anopheles gambiae, An. stephensi, An. freeborni, An. dirus and An. albimanus were found to exhibit hemagglutinating (lectin) activity. Lectin activity was not found for male An. gambiae, or female Ae aegypti, Culex quinquefasciatus, Phlebotomus duboscqi, and Lutzomyia longipalpis. With respect to species-specificity, An. gambiae SGH agglutinates red blood cells (RBC) from humans, horse, sheep, goat, pig, and cow; it is less active for rats RBC, and not detectable for guinea-pigs or chicken RBC. Notably, lectin activity was inhibited by low concentrations of dextran sulfate 50-500 K, fucoidan, heparin, laminin, heparin sulfate proteoglycan, sialyl-containing glycans (e.g. 3'-sialyl Lewis X, and 6'-sialyl lactose), and gangliosides (e.g. GM3, GD1, GD1b, GTB1, GM1, GQ1B), but not by simple sugars. These results imply that molecule(s) in the salivary gland target sulfated glycans. SGH from An. gambiae was also found to promote agglutination of HL-60 cells which are rich in sialyl Lewis X, a glycan that decorates PSGL-1, the neutrophils receptor that interacts with endothelial cell P-selectin. Accordingly, SGH interferes with HL-60 cells adhesion to immobilized P-selectin. Because An. gambiae SGH expresses galectins, one member of this family (herein named Agalectin) was expressed in E. coli. Recombinant Agalectin behaves as a non-covalent homodimer. It does not display lectin activity, and does not interact with 500 candidates tested in a Glycan microarray. Gel-filtration chromatography of the SGH of An. gambiae identified a fraction with hemagglutinating activity, which was analyzed by 1D PAGE followed by in-gel tryptic digestion, and nano-LC MS/MS. This approach identified several genes which emerge as candidates for a lectin targeting sulfated glycans, the first with this selectivity to be reported in the SGH of a blood-sucking arthropod. The role of salivary molecules (sialogenins) with lectin activity is discussed in the context of inflammation, and parasite-vector-host interactions.
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Examination of the ligand-binding and enzymatic properties of a bilin-binding protein from the poisonous caterpillar Lonomia obliqua.
PLoS ONE
PUBLISHED: 01-01-2014
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The bilin-binding proteins (BBP) from lepidopteran insects are members of the lipocalin family of proteins and play a special role in pigmentation through the binding of biliverdin IX?. Lopap, a BBP-like protein from the venom of the toxic caterpillar Lonomia obliqua has been reported to act as a serine protease that activates the coagulation proenzyme prothrombin. Here we show that BBPLo, a variant of lopap from the same organism binds biliverdin IX?, forming a complex that is spectrally identical with previously described BBP proteins. Although BBPLo is nearly identical in sequence to lopap, no prothrombinase activity was detected in our recombinant preparations using reconstituted systems containing coagulation factors Xa and Va, as well as anionic phospholipids. In addition to biliverdin, BBPLo was found to form a 1:1 complex with heme prompting us to examine whether the unusual biliverdin IX? ligand of BBPs forms as a result of oxidation of bound heme in situ rather than by a conventional heme oxygenase. Using ascorbate or a NADPH(+)-ferredoxin reductase-ferredoxin system as a source of reducing equivalents, spectral changes are seen that suggest an initial reduction of heme to the Fe(II) state and formation of an oxyferrous complex. The complex then disappears and a product identified as a 5-coordinate carbonyl complex of verdoheme, an intermediate in the biosynthesis of biliverdin, is formed. However, further reaction to form biliverdin was not observed, making it unlikely that biliverdin IX? is formed by this pathway.
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An insight into the transcriptome of the digestive tract of the bloodsucking bug, Rhodnius prolixus.
PLoS Negl Trop Dis
PUBLISHED: 01-01-2014
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The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7-8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for degradation of tyrosine, phenylalanine, and tryptophan. Analysis of transcripts related to signaling pathways suggested a role for MAP kinases, GTPases, and LKBP1/AMP kinases related to control of cell shape and polarity, possibly in connection with regulation of cell survival, response of pathogens and nutrients. Together, our findings present a new view of the triatomine digestive apparatus and will help us understand trypanosome interaction and allow insights into hemipteran metabolic adaptations to a blood-based diet.
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The king cobra genome reveals dynamic gene evolution and adaptation in the snake venom system.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 12-02-2013
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Snakes are limbless predators, and many species use venom to help overpower relatively large, agile prey. Snake venoms are complex protein mixtures encoded by several multilocus gene families that function synergistically to cause incapacitation. To examine venom evolution, we sequenced and interrogated the genome of a venomous snake, the king cobra (Ophiophagus hannah), and compared it, together with our unique transcriptome, microRNA, and proteome datasets from this species, with data from other vertebrates. In contrast to the platypus, the only other venomous vertebrate with a sequenced genome, we find that snake toxin genes evolve through several distinct co-option mechanisms and exhibit surprisingly variable levels of gene duplication and directional selection that correlate with their functional importance in prey capture. The enigmatic accessory venom gland shows a very different pattern of toxin gene expression from the main venom gland and seems to have recruited toxin-like lectin genes repeatedly for new nontoxic functions. In addition, tissue-specific microRNA analyses suggested the co-option of core genetic regulatory components of the venom secretory system from a pancreatic origin. Although the king cobra is limbless, we recovered coding sequences for all Hox genes involved in amniote limb development, with the exception of Hoxd12. Our results provide a unique view of the origin and evolution of snake venom and reveal multiple genome-level adaptive responses to natural selection in this complex biological weapon system. More generally, they provide insight into mechanisms of protein evolution under strong selection.
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Desmolaris, a novel factor XIa anticoagulant from the salivary gland of the vampire bat (Desmodus rotundus) inhibits inflammation and thrombosis in vivo.
Blood
PUBLISHED: 10-24-2013
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The identity of vampire bat saliva anticoagulant remained elusive for almost a century. Sequencing the salivary gland genes from the vampire bat Desmodus rotundus identified Desmolaris as a novel 21.5-kDa naturally deleted (Kunitz 1-domainless) form of tissue factor pathway inhibitor. Recombinant Desmolaris was expressed in HEK293 cells and characterized as a slow, tight, and noncompetitive inhibitor of factor (F) XIa by a mechanism modulated by heparin. Desmolaris also inhibits FXa with lower affinity, independently of protein S. In addition, Desmolaris binds kallikrein and reduces bradykinin generation in plasma activated with kaolin. Truncated and mutated forms of Desmolaris determined that Arg32 in the Kunitz-1 domain is critical for protease inhibition. Moreover, Kunitz-2 and the carboxyl-terminus domains mediate interaction of Desmolaris with heparin and are required for optimal inhibition of FXIa and FXa. Notably, Desmolaris (100 ?g/kg) inhibited FeCl3-induced carotid artery thrombus without impairing hemostasis. These results imply that FXIa is the primary in vivo target for Desmolaris at antithrombotic concentrations. Desmolaris also reduces the polyphosphate-induced increase in vascular permeability and collagen- and epinephrine-mediated thromboembolism in mice. Desmolaris emerges as a novel anticoagulant targeting FXIa under conditions in which the coagulation activation, particularly the contact pathway, plays a major pathological role.
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Multi-level modelling of physical activity in nuclear families.
Ann. Hum. Biol.
PUBLISHED: 10-11-2013
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Abstract Background: Few studies focus on the different dyadic relations among family members to study physical activity (PA) levels. Aim: The aim was to investigate predictors and sources of variance of PA levels in nuclear families using multi-level modelling. Subjects and methods: The sample consisted of 2661 Portuguese four-member nuclear families (10?644 subjects). PA was measured using a questionnaire and socioeconomic status (SES) was assessed by parental occupation. Height and weight were measured in children, while parents self-reported their values. Results: The results showed that intra-generational similarities were higher than inter-generational, with correlation values of 0.26 and 0.10, respectively. SES was unrelated to any family members PA level. Being male (??=?0.26, t?=?21.77), being older (??=?-0.36, t?=?-4.73) and greater BMI for mothers (??=?0.02, t?=?2.55) had effects on individuals PA. Conclusion: These results suggest a strong dyadic resemblance in PA, showed different effects of gender, age and BMI on individuals PA and demonstrated that multi-level modelling is a useful strategy to study PA in families.
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Novel family of insect salivary inhibitors blocks contact pathway activation by binding to polyphosphate, heparin, and dextran sulfate.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 10-03-2013
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Polyphosphate and heparin are anionic polymers released by activated mast cells and platelets that are known to stimulate the contact pathway of coagulation. These polymers promote both the autoactivation of factor XII and the assembly of complexes containing factor XI, prekallikrein, and high-molecular-weight kininogen. We are searching for salivary proteins from blood-feeding insects that counteract the effect of procoagulant and proinflammatory factors in the host, including elements of the contact pathway.
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Neonatal and pediatric manual hyperinflation: influence of oxygen flow on ventilation parameters.
Respir Care
PUBLISHED: 09-11-2013
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Although self-inflating bags are widely used for manual hyperinflation, they do not allow ventilation parameters, such as pressure or volume, to be set. We studied the ventilation performance of neonatal and pediatric self-inflating bags.
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Purification of a serine protease and evidence for a protein C activator from the saliva of the tick, Ixodes scapularis.
Toxicon
PUBLISHED: 08-27-2013
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The saliva of ticks is critical to their survival as parasites and hematophagous animals. In this study, we have purified an enzyme with trypsin-like activity from the saliva of the tick vector of Lyme Disease, Ixodes scapularis. This enzyme, named as IXOSP (I. scapularis salivary serine protease), is a 29.9 kDa molecule with N-terminus FPxMVxLRIKxR. A BLAST search identified IXOSP as a secreted serine protease (AAY66740) with a conserved catalytic triad His, Asp, and Ser. In vitro studies demonstrated that IXOSP cleaves chromogenic substrates with arginine in the P1 position, by a mechanism inhibited by PMSF or aprotinin. Gene expression studies revealed that IXOSP is expressed at different tick developmental stages, including eggs, and unfed or fed adult tick salivary glands, but not in nymphs or in the midgut. While the physiological substrate for IXOSP remains to be identified, we demonstrated that I. scapularis saliva activate protein C (PC) resulting in the production of activated PC, a potent anticoagulant that also regulates a myriad of inflammatory responses through protease activated receptors. In contrast, the salivary glands of Anopheles gambiae, Anopheles stephensi, Anopheles albimanus, Aedes aegypti, Lutzomyia longipalpis, and Phlebotomus ariasi did not activate protein C. These discoveries are discussed in the context of blood coagulation, inflammation and vector-host interactions.
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De novo Ixodes ricinus salivary gland transcriptome analysis using two next-generation sequencing methodologies.
FASEB J.
PUBLISHED: 08-20-2013
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Tick salivary gland (SG) proteins possess powerful pharmacologic properties that facilitate tick feeding and pathogen transmission. For the first time, SG transcriptomes of Ixodes ricinus, an important disease vector for humans and animals, were analyzed using next-generation sequencing. SGs were collected from different tick life stages fed on various animal species, including cofeeding of nymphs and adults on the same host. Four cDNA samples were sequenced, discriminating tick SG transcriptomes of early- and late-feeding nymphs or adults. In total, 441,381,454 pyrosequencing reads and 67,703,183 Illumina reads were assembled into 272,220 contigs, of which 34,560 extensively annotated coding sequences are disclosed; 8686 coding sequences were submitted to GenBank. Overall, 13% of contigs were classified as secreted proteins that showed significant differences in the transcript representation among the 4 SG samples, including high numbers of sample-specific transcripts. Detailed phylogenetic reconstructions of two relatively abundant SG-secreted protein families demonstrated how this study improves our understanding of the molecular evolution of hematophagy in arthropods. Our data significantly increase the available genomic information for I. ricinus and form a solid basis for future tick genome/transcriptome assemblies and the functional analysis of effectors that mediate the feeding physiology and parasite-vector interaction of I. ricinus.-Schwarz, A., von Reumont, B.M., Erhart, J., Chagas, A.C., Ribeiro, J.M.C., Kotsyfakis, M. De novo Ixodes ricinus salivary gland transcriptome analysis using two next-generation sequencing methodologies.
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A deep insight into the sialotranscriptome of the mosquito, Psorophora albipes.
BMC Genomics
PUBLISHED: 07-26-2013
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Psorophora mosquitoes are exclusively found in the Americas and have been associated with transmission of encephalitis and West Nile fever viruses, among other arboviruses. Mosquito salivary glands represent the final route of differentiation and transmission of many parasites. They also secrete molecules with powerful pharmacologic actions that modulate host hemostasis, inflammation, and immune response. Here, we employed next generation sequencing and proteome approaches to investigate for the first time the salivary composition of a mosquito member of the Psorophora genus. We additionally discuss the evolutionary position of this mosquito genus into the Culicidae family by comparing the identity of its secreted salivary compounds to other mosquito salivary proteins identified so far.
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The dance of male Anopheles gambiae in wild mating swarms.
J. Med. Entomol.
PUBLISHED: 06-28-2013
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An important element of mating in the malaria vector Anopheles gambiae Giles in nature is the crepuscular mating aggregation (swarm) composed almost entirely of males, where most coupling and insemination is generally believed to occur. In this study, we mathematically characterize the oscillatory movement of male An. gambiae in terms of an established individual-based mechanistic model that parameterizes the attraction of a mosquito toward the center of the swarm using the natural frequency of oscillation and the resistance to its motion, characterized by the damping ratio. Using three-dimensional trajectory data of ten wild mosquito swarms filmed in Mali, Africa, we show two new results for low and moderate wind conditions, and indicate how these results may vary in high wind. First, we show that in low and moderate wind the vertical component of the mosquito motion has a lower frequency of oscillation and higher damping ratio than horizontal motion. In high wind, the vertical and horizontal motions are similar to one another and the natural frequencies are higher than in low and moderate wind. Second, we show that the predicted average disagreement in the direction of motion of swarming mosquitoes moving randomly is greater than the average disagreement we observed between each mosquito and its three closest neighbors, with the smallest level of disagreement occurring for the nearest neighbor in seven out of 10 swarms. The alignment of the direction of motion between nearest neighbors is the highest in high wind. This result provides evidence for flight-path coordination between swarming male mosquitoes.
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Cross validation of ROC generated thresholds for field assessed aerobic fitness related to weight status and cardiovascular disease risk in Portuguese young people.
Am. J. Hum. Biol.
PUBLISHED: 06-16-2013
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To examine the efficacy of aerobic fitness thresholds in predicting weight status and cardiovascular disease risk (CVD) in young people.
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The genome of Anopheles darlingi, the main neotropical malaria vector.
Osvaldo Marinotti, Gustavo C Cerqueira, Luiz Gonzaga Paula de Almeida, Maria Inês Tiraboschi Ferro, Élgion Lúcio da Silva Loreto, Arnaldo Zaha, Santuza M R Teixeira, Adam R Wespiser, Alexandre Almeida E Silva, Aline Daiane Schlindwein, Ana Carolina Landim Pacheco, Artur Luiz da Costa da Silva, Brenton R Graveley, Brian P Walenz, Bruna de Araujo Lima, Carlos Alexandre Gomes Ribeiro, Carlos Gustavo Nunes-Silva, Carlos Roberto de Carvalho, Célia Maria de Almeida Soares, Claudia Beatriz Afonso de Menezes, Cleverson Matiolli, Daniel Caffrey, Demetrius Antonio M Araújo, Diana Magalhaes de Oliveira, Douglas Golenbock, Edmundo Carlos Grisard, Fabiana Fantinatti-Garboggini, Fabíola Marques de Carvalho, Fernando Gomes Barcellos, Francisco Prosdocimi, Gemma May, Gilson Martins de Azevedo Junior, Giselle Moura Guimarães, Gustavo Henrique Goldman, Itácio Q M Padilha, Jacqueline da Silva Batista, Jesus Aparecido Ferro, José M C Ribeiro, Juliana Lopes Rangel Fietto, Karina Maia Dabbas, Louise Cerdeira, Lucymara Fassarella Agnez-Lima, Marcelo Brocchi, Marcos Oliveira de Carvalho, Marcus de Melo Teixeira, Maria de Mascena Diniz Maia, Maria Helena S Goldman, Maria Paula Cruz Schneider, Maria Sueli Soares Felipe, Mariangela Hungria, Marisa Fabiana Nicolás, Maristela Pereira, Martín Alejandro Montes, Mauricio E Cantão, Michel Vincentz, Míriam Silva Rafael, Neal Silverman, Patrícia Hermes Stoco, Rangel Celso Souza, Renato Vicentini, Ricardo Tostes Gazzinelli, Rogério de Oliveira Neves, Rosane Silva, Spartaco Astolfi-Filho, Talles Eduardo Ferreira Maciel, Turán P Urményi, Wanderli Pedro Tadei, Erney Plessmann Camargo, Ana Tereza Ribeiro de Vasconcelos.
Nucleic Acids Res.
PUBLISHED: 06-12-2013
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Anopheles darlingi is the principal neotropical malaria vector, responsible for more than a million cases of malaria per year on the American continent. Anopheles darlingi diverged from the African and Asian malaria vectors ?100 million years ago (mya) and successfully adapted to the New World environment. Here we present an annotated reference A. darlingi genome, sequenced from a wild population of males and females collected in the Brazilian Amazon. A total of 10 481 predicted protein-coding genes were annotated, 72% of which have their closest counterpart in Anopheles gambiae and 21% have highest similarity with other mosquito species. In spite of a long period of divergent evolution, conserved gene synteny was observed between A. darlingi and A. gambiae. More than 10 million single nucleotide polymorphisms and short indels with potential use as genetic markers were identified. Transposable elements correspond to 2.3% of the A. darlingi genome. Genes associated with hematophagy, immunity and insecticide resistance, directly involved in vector-human and vector-parasite interactions, were identified and discussed. This study represents the first effort to sequence the genome of a neotropical malaria vector, and opens a new window through which we can contemplate the evolutionary history of anopheline mosquitoes. It also provides valuable information that may lead to novel strategies to reduce malaria transmission on the South American continent. The A. darlingi genome is accessible at www.labinfo.lncc.br/index.php/anopheles-darlingi.
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PfSETvs methylation of histone H3K36 represses virulence genes in Plasmodium falciparum.
Nature
PUBLISHED: 06-07-2013
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The variant antigen Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), which is expressed on the surface of P. falciparum-infected red blood cells, is a critical virulence factor for malaria. Each parasite has 60 antigenically distinct var genes that each code for a different PfEMP1 protein. During infection the clonal parasite population expresses only one gene at a time before switching to the expression of a new variant antigen as an immune-evasion mechanism to avoid the host antibody response. The mechanism by which 59 of the 60 var genes are silenced remains largely unknown. Here we show that knocking out the P. falciparum variant-silencing SET gene (here termed PfSETvs), which encodes an orthologue of Drosophila melanogaster ASH1 and controls histone H3 lysine 36 trimethylation (H3K36me3) on var genes, results in the transcription of virtually all var genes in the single parasite nuclei and their expression as proteins on the surface of individual infected red blood cells. PfSETvs-dependent H3K36me3 is present along the entire gene body, including the transcription start site, to silence var genes. With low occupancy of PfSETvs at both the transcription start site of var genes and the intronic promoter, expression of var genes coincides with transcription of their corresponding antisense long noncoding RNA. These results uncover a previously unknown role of PfSETvs-dependent H3K36me3 in silencing var genes in P. falciparum that might provide a general mechanism by which orthologues of PfSETvs repress gene expression in other eukaryotes. PfSETvs knockout parasites expressing all PfEMP1 proteins may also be applied to the development of a malaria vaccine.
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Genetic interaction of GSH metabolic pathway genes in cystic fibrosis.
BMC Med. Genet.
PUBLISHED: 06-07-2013
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Cystic fibrosis (CF) is a monogenic disease caused by CFTR gene mutations, with clinical expression similar to complex disease, influenced by genetic and environmental factors. Among the possible modifier genes, those associated to metabolic pathways of glutathione (GSH) have been considered as potential modulators of CF clinical severity. In this way it is of pivotal importance investigate gene polymorphisms at Glutamate-Cysteine Ligase, Catalytic Subunit (GCLC), Glutathione S-transferase Mu 1 (GSTM1), Glutathione S-transferase Theta 1 (GSTT1), and Glutathione S-transferase P1 (GSTP1), which have been associated to the GSH metabolic pathway and CF clinical severity.
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Expression of the mevalonate pathway enzymes in the Lutzomyia longipalpis (Diptera: Psychodidae) sex pheromone gland demonstrated by an integrated proteomic approach.
J Proteomics
PUBLISHED: 06-02-2013
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In Latin America, Lutzomyia longipalpis is the main vector of the protozoan parasite Leishmania infantum, which is the causal agent of American Visceral Leishmaniasis. This insect uses male-produced pheromones for mate recognition. Elucidation of pheromone biogenesis or its regulation may enable molecular strategies for mating disruption and, consequently, the vectors population management. Motivated by our recent results of the transcriptomic characterization of the L. longipalpis pheromone gland, we performed a proteomic analysis of this tissue combining SDS-PAGE, and mass spectrometry followed by an integrative data analysis. Considering that annotated genome sequences of this sand fly are not available, we designed an alternative workflow searching MS/MS data against two customized databases using three search engines: Mascot, OMSSA and ProLuCID. A total of 542 proteins were confidently characterized, 445 of them using a Uniref100-insect protein database, and 97 using a transcript translated database. In addition, use of PEAKS for de novo peptide sequencing of MS/MS data confirmed ~90% identifications made with the combination of the three search engines. Our results include the identification of six of the seven enzymes of the mevalonate-pathway, plus the enzymes involved in sesquiterpenoid biosynthesis, all of which are proposed to be involved in pheromone production in L. longipalpis.
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Hyperbaric oxygen therapy for primary sternal osteomyelitis: a case report.
J Med Case Rep
PUBLISHED: 05-30-2013
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Primary osteomyelitis of the sternum is a rare condition, which accounts for 0.3% of all cases of osteomyelitis reported in the literature. The diagnosis requires a high degree of suspicion and confirmation by percutaneous biopsy. The treatment consists of resection of the periosteum and affected bone. Despite reports of successful conservative treatment using antibiotics alone, early surgical intervention plus bacterial control is the definitive treatment; it reduces morbidity, and is the most cost-effective approach for the patient. We report a case of primary osteomyelitis surgically treated with debridement and antibiotics, followed by hyperbaric oxygen therapy.
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Effect of exercise test on pulmonary function of obese adolescents.
J Pediatr (Rio J)
PUBLISHED: 05-27-2013
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to investigate the pulmonary response to exercise of non-morbidly obese adolescents, considering the gender.
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APC germline mutations in families with familial adenomatous polyposis.
Oncol. Rep.
PUBLISHED: 05-24-2013
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Adenomatous polyposis coli (APC) germline mutations are responsible for the occurrence of familial adenomatous polyposis (FAP). Somatic mutations lead to malignant transformation of adenomas. In this context, considering the significance of APC germline mutations in FAP, we aimed to identify APC germline mutations. In the present study, 20 FAP patients were enrolled. The determination of APC germline mutations was performed using sequencing, and the mutations were compared with clinical markers (gender, age at diagnosis, smoking habits, TNM stage, Astler?Coller stage, degree of differentiation of adenocarcinoma). The data were compared using the SPSS program, with the Fishers exact test and ?2 test, considering ?=0.05. According to the main results in our sample, 16 alleles with deleterious mutations (80% of the patients) were identified while 7 (35%) patients had no deleterious mutations. There was a predominance of nonsense (45% of the patients) and frameshift (20% of the patients) mutations. There was no statistical significance between the APC germline mutations identified and the clinical variables considered in our study. Only TNM stage was associated with the presence of deleterious mutations. Patients with deleterious mutations had an OR, 0.086 (IC=0.001-0.984); TNM stage I+II in comparison with III+IV, when compared with the patients with no deleterious mutations identified. In this context, as a conclusion, we demonstrated the molecular heterogeneity of APC germline mutations in FAP and the difficulty to perform molecular diagnostics in a Brazilian population, considering the admixed population analyzed.
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Cystic fibrosis transmembrane conductance regulator mutations at a referral center for cystic fibrosis.
J Bras Pneumol
PUBLISHED: 05-15-2013
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To determine the frequency of six mutations (F508del, G542X, G551D, R553X, R1162X, and N1303K) in patients with cystic fibrosis (CF) diagnosed, at a referral center, on the basis of abnormal results in two determinations of sweat sodium and chloride concentrations.
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Walk test and school performance in mouth-breathing children.
Braz J Otorhinolaryngol
PUBLISHED: 05-15-2013
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In recent decades, many studies on mouth breathing (MB) have been published; however, little is known about many aspects of this syndrome, including severity, impact on physical and academic performances.
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Functional transcriptomics of wild-caught Lutzomyia intermedia salivary glands: identification of a protective salivary protein against Leishmania braziliensis infection.
PLoS Negl Trop Dis
PUBLISHED: 05-01-2013
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Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects salivary components that change the environment at the feeding site. Mice immunized with Phlebotomus papatasi salivary gland (SG) homogenate are protected against Leishmania major infection, while immunity to Lutzomyia intermedia SG homogenate exacerbated experimental Leishmania braziliensis infection. In humans, antibodies to Lu. intermedia saliva are associated with risk of acquiring L. braziliensis infection. Despite these important findings, there is no information regarding the repertoire of Lu. intermedia salivary proteins.
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Associations between sports participation, levels of moderate to vigorous physical activity and cardiorespiratory fitness in childrenand adolescents.
J Sports Sci
PUBLISHED: 04-30-2013
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The purpose of this study was to analyse the associations between sports participation, levels of moderate to vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF). The study comprised 310 participants (183 girls and 127 boys) aged 11-18 years. Sports participation was assessed by questionnaire and habitual physical activity (PA) was measured objectively with accelerometers. The 20-m shuttle-run test was used to estimate CRF. Logistic regression analyses were carried out with CRF as the outcome. The odds ratio (OR) for being fit was greater for those who comply with 60 min · day(-1) in MVPA (OR = 2.612; 95%confidence interval [CI] = 1.614-4.225) in comparison with those who do not. Participation in competitive sports at club levels increased the chances of being fit (OR = 13.483; 95%CI = 4.560-39.864), independently of MVPA levels. There were positive and significant trends in CRF and objectively measured PA across the levels of engagement in competitive sports (P < 0.05). Concluding, participation in competitive sports at club level is more effective than other organised or non-organised sports to reach healthier levels of CRF and recommend levels of MVPA.
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Stereoscopic video analysis of Anopheles gambiae behavior in the field: Challenges and opportunities.
Acta Trop.
PUBLISHED: 04-17-2013
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Advances in our ability to localize and track individual swarming mosquitoes in the field via stereoscopic image analysis have enabled us to test long-standing ideas about individual male behavior and directly observe coupling. These studies further our fundamental understanding of the reproductive biology of mosquitoes. In addition, our analyses using stereoscopic video of swarms of the African malaria vector Anopheles gambiae have produced results that should be relevant to any "release-based" method of control including Sterile Insect Technique (SIT) and genetically modified male mosquitoes (GMM). The relevance of the results is primarily due to the fact that any mosquito vectors released for control are almost certainly going to be males; further, for SIT, GMM or similar approaches to be successful, the released males will have to successfully locate swarms and then mate with wild females. Thus, understanding and potentially manipulating the mating process could play a key role in future control programs. Our experience points to special challenges created by stereoscopic video of swarms. These include the expected technical difficulties of capturing usable images of mosquitoes in the field, and creating an automated tracking system to enable generation of large numbers of three dimensional tracks over many seconds of footage. Once the data are collected, visualization and application of appropriate statistical and analytic methods also are required. We discuss our recent progress on these problems, give an example of a statistical approach to quantify individual male movement in a swarm with some novel results, and suggest further studies incorporating experimental manipulation and three dimensional localization and tracking of individual mosquitoes in wild swarms.
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Salivary antigen-5/CAP family members are Cu2+-dependent antioxidant enzymes that scavenge O??. and inhibit collagen-induced platelet aggregation and neutrophil oxidative burst.
J. Biol. Chem.
PUBLISHED: 04-05-2013
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The function of the antigen-5/CAP family of proteins found in the salivary gland of bloodsucking animals has remained elusive for decades. Antigen-5 members from the hematophagous insects Dipetalogaster maxima (DMAV) and Triatoma infestans (TIAV) were expressed and discovered to attenuate platelet aggregation, ATP secretion, and thromboxane A2 generation by low doses of collagen (<1 ?g/ml) but no other agonists. DMAV did not interact with collagen, glycoprotein VI, or integrin ?2?1. This inhibitory profile resembles the effects of antioxidants Cu,Zn-superoxide dismutase (Cu,Zn-SOD) in platelet function. Accordingly, DMAV was found to inhibit cytochrome c reduction by O2[Symbol: see text] generated by the xanthine/xanthine oxidase, implying that it exhibits antioxidant activity. Moreover, our results demonstrate that DMAV blunts the luminescence signal of O2[Symbol: see text] generated by phorbol 12-myristate 13-acetate-stimulated neutrophils. Mechanistically, inductively coupled plasma mass spectrometry and fluorescence spectroscopy revealed that DMAV, like Cu,Zn-SOD, interacts with Cu(2+), which provides redox potential for catalytic removal of O2[Symbol: see text]. Notably, surface plasmon resonance experiments (BIAcore) determined that DMAV binds sulfated glycosaminoglycans (e.g. heparin, KD ~100 nmol/liter), as reported for extracellular SOD. Finally, fractions of the salivary gland of D. maxima with native DMAV contain Cu(2+) and display metal-dependent antioxidant properties. Antigen-5/CAP emerges as novel family of Cu(2+)-dependent antioxidant enzymes that inhibit neutrophil oxidative burst and negatively modulate platelet aggregation by a unique salivary mechanism.
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Socioeconomic Status and Objectively Measured Physical Activity in Thai Adolescents.
J Phys Act Health
PUBLISHED: 03-14-2013
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BACKGROUND: The impact of socioeconomic status (SES) on objective measures of physical activity (PA) in adolescence is poorly understood. The purpose of this cross-sectional study was to evaluate the association between SES and objectively measured PA in Thai adolescents. METHODS: PA was objectively measured every 30 seconds for 7 consecutive days using ActiGraph GT1M uniaxial accelerometers in 177 secondary-school adolescents aged 13-18 years that were classified into 3 SES groups (low, middle and high). The associations between SES and adolescents PA were examined using 1-way ANOVA with multiple comparisons and Chi-square test. RESULTS: Adolescents of low-SES accumulated more minutes of PA and less of sedentary behavior than those of high-SES, Additionally, low-SES adolescents tended to meet the daily PA guidelines more than other groups, particularly in girls (P < 0.01). CONCLUSIONS: This study evidences an inverse relationship between SES and PA levels, and shows the importance of targeting high SES adolescents in intervention programs to enhance health behaviors. Based on these findings, we also suggest that SES must be considered as an important determinant in promoting regular PA and in increasing proportions of adolescents meeting current health-related PA guidelines.
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Saliva as a potential tool for cystic fibrosis diagnosis.
Diagn Pathol
PUBLISHED: 03-10-2013
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Saliva and sweat are modified by cystic fibrosis (CF). In both cases the chloride and sodium ion concentrations for healthy subjects and CF patients differ, this representing a possible alternative tool for CF diagnosis. In this context, the aim of this study was to compare the concentrations of these ions in saliva samples taken from CF patients and healthy subjects.
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Genomics of Loa loa, a Wolbachia-free filarial parasite of humans.
Nat. Genet.
PUBLISHED: 02-22-2013
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Loa loa, the African eyeworm, is a major filarial pathogen of humans. Unlike most filariae, L. loa does not contain the obligate intracellular Wolbachia endosymbiont. We describe the 91.4-Mb genome of L. loa and that of the related filarial parasite Wuchereria bancrofti and predict 14,907 L. loa genes on the basis of microfilarial RNA sequencing. By comparing these genomes to that of another filarial parasite, Brugia malayi, and to those of several other nematodes, we demonstrate synteny among filariae but not with nonparasitic nematodes. The L. loa genome encodes many immunologically relevant genes, as well as protein kinases targeted by drugs currently approved for use in humans. Despite lacking Wolbachia, L. loa shows no new metabolic synthesis or transport capabilities compared to other filariae. These results suggest that the role of Wolbachia in filarial biology is more subtle than previously thought and reveal marked differences between parasitic and nonparasitic nematodes.
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Transcriptome exploration of the sex pheromone gland of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae).
Parasit Vectors
PUBLISHED: 02-19-2013
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Molecules involved in pheromone biosynthesis may represent alternative targets for insect population control. This may be particularly useful in managing the reproduction of Lutzomyia longipalpis, the main vector of the protozoan parasite Leishmania infantum in Latin America. Besides the chemical identity of the major components of the L. longipalpis sex pheromone, there is no information regarding the molecular biology behind its production. To understand this process, obtaining information on which genes are expressed in the pheromone gland is essential.
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Screening for F508del as a first step in the molecular diagnosis of cystic fibrosis.
J Bras Pneumol
PUBLISHED: 02-15-2013
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To determine the relevance of screening for the F508del mutation of the cystic fibrosis transmembrane conductance regulator gene as a first step in the genetic diagnosis of cystic fibrosis (CF) by associating the genotype with various clinical variables.
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Pseudomonas aeruginosa infection in patients with cystic fibrosis: scientific evidence regarding clinical impact, diagnosis, and treatment.
J Bras Pneumol
PUBLISHED: 02-11-2013
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Evidence-based techniques have been increasingly used in the creation of clinical guidelines and the development of recommendations for medical practice. The use of levels of evidence allows the reader to identify the quality of scientific information that supports the recommendations made by experts. The objective of this review was to address current concepts related to the clinical impact, diagnosis, and treatment of Pseudomonas aeruginosa infections in patients with cystic fibrosis. For the preparation of this review, the authors defined a group of questions that would be answered in accordance with the principles of PICO-an acronym based on questions regarding the Patients of interest, Intervention being studied, Comparison of the intervention, and Outcome of interest. For each question, a structured review of the literature was performed using the Medline database in order to identify the studies with the methodological design most appropriate to answering the question. The questions were designed so that each of the authors could write a response. A first draft was prepared and discussed by the group. Recommendations were then made on the basis of the level of scientific evidence, in accordance with the classification system devised by the Oxford Centre for Evidence-Based Medicine, as well as the level of agreement among the members of the group.
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Manual therapy for childhood respiratory disease: a systematic review.
J Manipulative Physiol Ther
PUBLISHED: 02-06-2013
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This study reviewed the scientific evidence available on the effects of manipulative techniques on children with respiratory diseases.
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Electrochemical study of the anticancer drug daunorubicin at a water/oil interface: drug lipophilicity and quantification.
Anal. Chem.
PUBLISHED: 01-24-2013
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In this work, the ion transfer mechanism of the anticancer drug daunorubicin (DNR) at a liquid/liquid interface has been studied for the first time. This study was carried out using electrochemical techniques, namely cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The lipophilicity of DNR was investigated at the water/1,6-dichlorohexane (DCH) interface, and the results obtained were presented in the form of an ionic partition diagram. The partition coefficients of both neutral and ionic forms of the drug were determined. The analytical parameter for the detection of DNR was also investigated in this work. An electrochemical DNR sensor is proposed by means of simple ion transfer at the water/DCH interface, using DPV as the quantification technique. Experimental conditions for the analytical determination of DNR were established, and a detection limit of 0.80 ?M was obtained.
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Epidemiological and genetic characteristics associated with the severity of acute viral bronchiolitis by respiratory syncytial virus.
J Pediatr (Rio J)
PUBLISHED: 01-22-2013
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to assess the epidemiological and genetic factors associated with severity of acute viral bronchiolitis (AVB) by respiratory syncytial virus (RSV).
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Severe lower respiratory tract infection in infants and toddlers from a non-affluent population: viral etiology and co-detection as risk factors.
BMC Infect. Dis.
PUBLISHED: 01-21-2013
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Lower respiratory tract infection (LRTI) is a major cause of pediatric morbidity and mortality, especially among non-affluent communities. In this study we determine the impact of respiratory viruses and how viral co-detections/infections can affect clinical LRTI severity in children in a hospital setting.
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Cardiorespiratory fitness and TV viewing in relation to metabolic risk factors in Portuguese adolescents.
Ann. Hum. Biol.
PUBLISHED: 01-18-2013
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The purpose of this study was to examine whether adolescents who have high levels of cardiorespiratory fitness (CRF) co-existing with low levels of television (TV) viewing present a better metabolic risk profile compared to their low fit and high TV viewing counterparts.
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Associations between body mass index, waist circumference and body shape index with resting blood pressure in Portuguese adolescents.
Ann. Hum. Biol.
PUBLISHED: 01-18-2013
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Elevated blood pressure (BP) in childhood and adolescence is associated with overweight and obesity. Recently a body shape index (ABSI) has been suggested as superior to body mass index (BMI, kg/m(2)) and waist circumference (WC) as a measure of disease risk.
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Is walking to school associated with improved metabolic health?
Int J Behav Nutr Phys Act
PUBLISHED: 01-15-2013
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Active commuting to/from school is an important source of physical activity that has been declining over the past years. Although it is an affordable and simple way of increasing physical activity levels it is still unclear whether it has enough potential to improve health. Therefore, the aim of this cross sectional study was to examine the relationship between active commuting to/from school and metabolic risk factors in 10 to 12 year old children.
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What is Visualize?

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

How does it work?

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

Video X seems to be unrelated to Abstract Y...

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.