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Find video protocols related to scientific articles indexed in Pubmed.
pH-Driven Colloidal Transformations Based on the Vasoactive Drug Nicergoline.
Langmuir
PUBLISHED: 11-20-2014
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The structure of colloidal self-assembled drug delivery systems can be influenced by intermolecular interactions between drug and amphiphilic molecules, and is important to understand in the context of designing improved delivery systems. Controlling these structures can enable controlled or targeted release systems for poorly water-soluble drugs. Here we present the interaction of the hydrophobic vasoactive drug nicergoline with the internal structure of nanostructured emulsion particles based on the monoglyceride - water system. Addition of this drug leads to modification of the internal bicontinuous cubic structure to generate highly pH responsive systems. The colloidal structures were characterized with small angle X-ray scattering and visualized using cryogenic transmission electron microscopy. Reversible transformations to inverse micelles at high pH, vesicles at low pH and the modification of the spacing of the bicontinuous cubic structure at intermediate pH were observed, and enabled the in situ determination of an apparent pKa for the drug in this system - a difficult task using solution-based approaches. The characterization of this phase behavior is also highly interesting for the design of pH responsive controlled release systems for poorly water-soluble drug molecules.
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Spectro-microscopic photoemission evidence of charge uncompensated areas in Pb(Zr,Ti)O3(001) layers.
Phys Chem Chem Phys
PUBLISHED: 11-20-2014
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Photoelectron spectroscopy studies of (001) oriented PbTi0.8Zr0.2O3 (PZT) single crystal layers with submicron resolution revealed areas with different Pb 5d binding energies, attributed to the different charge and polarization states of the film surface. Two novel effects are evidenced by using intense synchrotron radiation beam experiments: (i) the progressive increase of a low binding energy component for the Pb core levels (evidenced for both 5d and 4f, on two different measurement setups), which can be attributed to a partial decomposition of the PZT film at its surface and promoting the growth of metallic Pb during the photoemission process, with the eventuality of the progressive formation of areas with downwards ferroelectric polarization; (ii) for films annealed in oxygen under clean conditions (in an ultrahigh vacuum installation) a huge shift of the Pb 5d core levels (by 8-9 eV) towards higher binding energies is attributed to the formation of areas with depleted mobile charge carriers, whose surface density is insufficient to screen the depolarization field. This shift is attenuated progressively with time, as the sample is irradiated with high flux soft X-rays. The formation of these areas with strong internal electric field promotes these films as good candidates for photocatalysis and solar cells, since in the operation of these devices the ability to perform charge separation and to avoid electron-hole recombination is crucial.
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Development and application of a non-targeted extraction method for the analysis of migrating compounds from plastic baby bottles by GC-MS.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess
PUBLISHED: 11-20-2014
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In 2011, the European Union prohibited the production of polycarbonate (PC) baby bottles due to the toxic effects of the PC monomer bisphenol-A. Therefore, baby bottles made of alternative materials, e.g. polypropylene (PP) or polyethersulphone (PES), are currently marketed. The principal aim of the study was the identification of major compounds migrating from baby bottles using a liquid-liquid extraction followed by GC/MS analysis. A 50% EtOH in water solution was selected as a simulant for milk. After sterilisation of the bottle, three migration experiments were performed during 2 h at 70°C. A non-targeted liquid-liquid extraction with ethyl acetate-n-hexane (1:1) was performed on the simulant samples. Identification of migrants from 24 baby bottles was done using commercially available WILEY and NIST mass spectra libraries. Differences in the migrating compounds and their intensities were observed between the different types of plastics, but also between the same polymer from a different producer. Differences in the migration patterns were perceived as well between the sterilisation and the migrations and within the different migrations. Silicone, Tritan™ and PP exhibited a wide variety of migrating compounds, whereas PES and polyamide (PA) showed a lower amount of migrants, though sometimes in relatively large concentrations (azacyclotridecan-2-one up to 250 µg kg(-1)). Alkanes (especially in PP bottles), phthalates (dibutylphthalate in one PP bottle (±40 µg kg(-1)) and one silicone bottle (±25 µg kg(-1)); diisobutylphthalate in one PP (±10 µg kg(-1)), silicone (up to ±80 µg kg(-1)); and Tritan™ bottle (±30 µg kg(-1))), antioxidants (Irgafos 168, degradation products of Irganox 1010 and Irganox 1076), etc. were detected for PP, silicone and Tritan™ bottles. Although the concentrations were relatively low, some compounds not authorised by European Union Regulation No. 10/2011, such as 2,4-di-tert-butylphenol (10-100 µg kg(-1)) or 2-butoxyethyl acetate (about 300 µg kg(-1)) were detected. Migrating chemicals were identified as confirmed (using a standard) or as tentative (further confirmation required).
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Urinary Biomonitoring of Phosphate Flame Retardants: Levels in California Adults and Recommendations for Future Studies.
Environ. Sci. Technol.
PUBLISHED: 11-13-2014
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Phosphate flame retardants (PFRs) are abundant and found at the highest concentrations relative to other flame retardant chemicals in house dust; however, little is known about the biological levels of PFRs and their relationship with house dust concentrations. These relationships provide insight into major exposure pathways and potential health risks. We analyzed urine samples from 16 California residents in 2011 for 6 chlorinated and nonchlorinated dialkyl or diaryl phosphates (DAPs), the expected major metabolites of the most prominent PFRs, and qualitatively screened for 18 other metabolites predicted from in vitro studies. We detected all 6 DAPs within the range of previously reported levels, although very few comparisons are available. We found weakly positive nonsignificant correlations between urine and dust concentrations and maxima urine corresponding to maxima dust for the pairs bis(1,3-dichloro-2-propyl) phosphate (BDCIPP)-tris(1,3-dichloro-isopropyl) phosphate (TDCIPP) and bis(2-chloroethyl) phosphate (BCEP)-tris(2-chloroethyl) phosphate (TCEP). Metabolite levels of PFRs were correlated for many PFR combinations, suggesting they commonly co-occur. As far as we know, this is the first study to measure these 6 DAP metabolites simultaneously and to detect other PFR metabolites in US urine samples. We recommend biomonitoring studies include these 6 DAPs as well as several additional compounds detected through qualitative screening and previous ADME studies. PFRs represent a class of poorly studied commercial chemicals with widespread exposure and raise concerns for health effects including carcinogenicity and neurotoxicity.
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Hypochondriacal attitudes and beliefs, attitudes towards complementary and alternative medicine and modern health worries predict patient satisfaction.
JRSM Open
PUBLISHED: 11-01-2014
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To investigate how hypochondriacal attitudes and beliefs, attitudes towards complementary and alternative medicine (CAM) and modern health worries (MHWs) related to patient satisfaction with their general practitioner.
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A Bright Side, Facet Analysis of Histrionic Personality Disorder: The Relationship Between the HDS Colourful Factor and the NEO-PI-R Facets in a Large Adult Sample.
J Soc Psychol
PUBLISHED: 10-04-2014
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This study looks at "bright-side," Big Five Personality trait correlates of a "dark-side" Personality Disorder, namely Histrionic Personality Disorder (HPD). More than 5000 British adults completed the Neuroticism Extraversion Openness Personality Inventory-Revised (Costa & McCrae, 1985), which measures the Big Five Personality factors at the Domain (Super Factor) and the Facet (Factor) level, as well as the Hogan Development Survey (HDS; Hogan & Hogan, 2009), which has a measure of HPD, exclusively called "Colourful" in the HDS terminology. Correlation and regression results confirmed many of the associations between these "bright" and "dark" side individual difference variables. The Colourful (HPD) score from the HDS was the criterion variable in all analyses. Colourful individuals are high on Extraversion and Openness, but also Stable and Disagreeable. The Facet analysis identified Assertiveness and Immodesty as particularly characteristic of that type. The study confirmed work on HPD using different population groups and different measures, showing that personality traits are predictable and correlated with various personality disorders.
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Development of a broad spectrum method for measuring flame retardants - overcoming the challenges of non-invasive human biomonitoring studies.
Anal Bioanal Chem
PUBLISHED: 08-30-2014
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Flame retardants (FRs), such as polybrominated diphenyl ethers (PBDEs) and phosphate flame retardants (PFRs), are a diverse group of compounds that are used to improve fire safety in many consumer products, such as furniture, textiles, electronics, etc. As these compounds are potentially harmful for human health, there is a need to better understand human exposure. Exposure to environmental contaminants can be monitored by the measurement of external sources of exposures and also by the determination of contaminant levels in human samples. For ethical and practical reasons, noninvasive matrices, such as hair, are preferred but, unfortunately, not widely used due to methodological limitations. A major challenge is sample availability: only small amounts can be sampled per individual. Multi-residue methods are therefore essential in order to determine multiple compounds in low sample amounts. In the framework of the FP7 project (INFLAME), an analytical method for the simultaneous determination of PBDEs and PFRs in human hair has been optimized and validated. Before extraction, hair samples (200 mg) were denaturated in nitric acid (HNO3) for 25 min at 25 °C. Consecutively, the samples were extracted using a mixture of hexane:dichloromethane, and extracts were further fractionated on Florisil. Fraction A which contained PBDEs was additionally cleaned on acidified silica gel and measured by gas chromatography coupled with electron capture negative ionization mass spectrometry (GC-ECNI-MS), while fraction B containing PFRs was directly analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). This approach resulted in recoveries between 81-120% for PBDEs and 75-113% for PFRs (relative standard deviation (RSD)?
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Fingerprint of persistent organic pollutants in tissues of Antarctic notothenioid fish.
Sci. Total Environ.
PUBLISHED: 08-29-2014
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In the present work, persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and metabolites, polybrominated diphenyl ethers (PBDEs), and hexachlorocyclohexane (HCH) were analyzed in three Antarctic notothenioids fish species: Trematomus newnesi (TRN), Notothenia coriiceps (NOC) and Notothenia rossii (NOR). The contribution of each POP-family to the total load was as follows: ?PCB (40%)>?DDT (27%)>?PBDEs (23%)>?HCH (10%). Among the 23 PCB congeners analyzed, penta-CBs homologues were the prevalent group, followed by hexa-CBs and hepta-CBs. DDT and its metabolites presented the following trend: p,p'-DDT>p,p'-DDE~p,p'-DDD. PBDE profile was dominated by BDE-47 and BDE-99 congeners, followed by BDE-100>BDE-28>BDE-154, BDE-153. Among HCHs, the ?-HCH isomer was detected in all samples, constituting 69% total HCH load, while ?-HCH and ?-HCH contributions were 15% and 16%, respectively. The levels of POPs reported here suggest that NOR and NOC are more susceptible to accumulate the analyzed contaminants than TRN, a species not previously analyzed for POPs. Distribution of POPs among different tissues of the three species (muscle, liver, gonads, and gills) was also investigated. Considering lipid weight, the general pattern of POPs distribution in tissues indicated that while gonads showed higher levels of PCBs, DDTs and HCH, the most significant PBDE concentrations were recorded in gills. Also, a comparative analysis of POPs concentration in fish samples from Antarctic area was included.
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Determinants of bisphenol A and phthalate metabolites in urine of Flemish adolescents.
Environ. Res.
PUBLISHED: 08-12-2014
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As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and different phthalate metabolites were analyzed, for the first time, in the urine of 210 adolescents in Flanders, Belgium. All chemicals had a detection frequency above 90%. For all compounds, except the sum of DEHP, highest levels were detected during spring. Average values for the Flemish adolescents were in an agreement with concentrations found in different international studies, all confirming the ubiquity of BPA and phthalate exposure. There was a significant correlation between BPA and the different phthalate metabolites (r between 0.26 and 0.39; p<0.01). Shared sources of exposure to BPA and phthalates, such as food packaging, were suggested to be responsible for this positive correlation. Different determinants of exposure were evaluated in relation to the urinary concentrations of these chemicals. For BPA, a significant association was observed with household income class, smoking and exposure to environmental tobacco smoke. For phthalates, the following significant associations were observed: age (MBzP), educational level of the adolescent (MBzP), equivalent household income (MnBP), use of personal care products (MnBP and MBzP), wall paper in house (MnBP and MBzP) and use of local vegetables (MnBP and MBzP).
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Cultural and age differences in beliefs about depression: British Bangladeshis vs. British Whites.
Ment Health Relig Cult
PUBLISHED: 08-01-2014
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This study examines beliefs about depression as a function of ethnic background (British Bangladeshis vs. British Whites) and age. A total of 364 participants completed a 65-item questionnaire, containing general questions regarding depression and anti-depressive behaviour; the causes of depression, and treatments for depression. The hypotheses were broadly supported; there were significant interactions between ethnicity and age, which generally revealed an increasingly negative attitude towards depression with increasing age amongst British Bangladeshis. Older British Bangladeshis believed depression was an illness that brought a sense of shame and loss of dignity to the individual and his or her family, and they also favoured a lay referral system for sufferers. They also had more superstitious beliefs about depression than both younger British Bangladeshis and British Whites. A pattern of increasing negativity with increasing age was not evident amongst the British Whites, but older individuals in both groups tended to believe that depression was not helped by psychological intervention. The attitudes towards depression in the young was similar (and generally positive) in both ethnic groups. These findings highlight the necessity to provide more culturally sensitive and accessible services for migrant communities - particularly amongst older individuals.
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Age dependent differences in collagen alignment of glutaraldehyde fixed bovine pericardium.
Biomed Res Int
PUBLISHED: 07-17-2014
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Bovine pericardium is used for heart valve leaflet replacement where the strength and thinness are critical properties. Pericardium from neonatal animals (4-7 days old) is advantageously thinner and is considered as an alternative to that from adult animals. Here, the structures of adult and neonatal bovine pericardium tissues fixed with glutaraldehyde are characterized by synchrotron-based small angle X-ray scattering (SAXS) and compared with the mechanical properties of these materials. Significant differences are observed between adult and neonatal tissue. The glutaraldehyde fixed neonatal tissue has a higher modulus of elasticity (83.7?MPa) than adult pericardium (33.5?MPa) and a higher normalised ultimate tensile strength (32.9?MPa) than adult pericardium (19.1?MPa). Measured edge on to the tissue, the collagen in neonatal pericardium is significantly more aligned (orientation index (OI) 0.78) than that in adult pericardium (OI 0.62). There is no difference in the fibril diameter between neonatal and adult pericardium. It is shown that high alignment in the plane of the tissue provides the mechanism for the increased strength of the neonatal material. The superior strength of neonatal compared with adult tissue supports the use of neonatal bovine pericardium in heterografts.
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Distribution patterns of brominated, chlorinated, and phosphorus flame retardants with particle size in indoor and outdoor dust and implications for human exposure.
Environ. Sci. Technol.
PUBLISHED: 07-17-2014
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Dust samples were collected in Beijing, China, from four different indoor microenvironments (office, hotel, kindergarten, and student dormitory) and one outdoor (road dust) microenvironment. These five composite samples were fractionated into 13 sequential size fractions and an individual fraction of <50 ?m for further analysis. In the fractions of <50 ?m, nine phosphorus flame retardants (?PFRs), four novel brominated flame retardants (?NBFRs), and two Dechlorane Plus isomers (DPs) showed the highest concentrations in hotel dust (124,000 ng g(-1)), dormitory dust (14,200 ng g(-1)), and kindergarten dust (231 ng g(-1)), respectively. Nevertheless, nine polybrominated diphenyl ethers (?PBDEs) were the dominant flame retardants (FRs) (96% of total FRs) in road dust, with the maximum concentration of 23,700 ng g(-1), higher than in any indoor dust. The FR contamination varied strongly among different types of microenvironments, leading to high human exposure to various FRs. Concentrations of FRs did not increase constantly with a particle size decrease. Fractions with a particle size around 900, 100, and 10 ?m could represent peak values, while valley values were commonly detected around fractions with a particle size around 40 ?m. Large differences were found between indoor dust and road dust. In road dust, FRs were mainly enriched in fractions of <50 ?m. The organic content of dust, FR application, and consequent abrasion processes of FR-containing materials might be the determinants of the FR concentrations. Volatilization and abrasion were considered to be important migration pathways for FRs. DPs and BDE-209 were sought to be mainly applied in abrasion-proof materials, while most phosphorus flame retardants (PFRs) were probably added in a large proportion in materials easy to wear.
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Exposure to persistent organic pollutants: relationship with abnormal glucose metabolism and visceral adiposity.
Diabetes Care
PUBLISHED: 06-26-2014
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The contribution of persistent organic pollutants (POPs) to the pandemic of type 2 diabetes mellitus and obesity has been assumed but remains speculative. Our study aimed at investigating the relationship of POP levels with detailed markers of glucose metabolism and body composition.
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Age as a determinant of phosphate flame retardant exposure of the Australian population and identification of novel urinary PFR metabolites.
Environ Int
PUBLISHED: 06-19-2014
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The demand for alternative flame retardant materials such as phosphate flame retardants and plasticizers (PFRs) is increasing, although little is known of their possible effects on human health and development. To date, no information on the exposure of children or general Australian population to PFRs is available. The objectives of this study were to characterize the average levels and age-related patterns of PFR metabolites in urine in the general Australian population and to identify novel hydroxylated PFR metabolites in urine. Surplus pathology urine samples from Queensland, Australia were stratified and pooled by age and sex (3224 individuals aged 0 to 75years into 95 pools) according to two different pooling strategies at two different time periods. Samples were analyzed by solid phase extraction and liquid chromatography-tandem mass spectrometry following enzymatic treatment. Nine PFR metabolites were measured in the Australian population, including the first report of a hydroxylated metabolite of TCIPP (BCIPHIPP). Diphenyl phosphate (DPHP), BCIPHIPP and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) were detected in >95% of samples. DPHP, a metabolite of aryl-PFRs, was found in several samples at levels which were one order of magnitude higher than previously reported (up to 730ng/mL). Weighted linear regression revealed a significant negative association between log-normalized BDCIPP and DPHP levels and age (p<0.001). Significantly greater levels of BDCIPP and DPHP were found in children's urine compared with adults, suggesting higher exposure to PFRs in young children. BCIPHIPP was identified for inclusion in future PFR biomonitoring studies.
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Perfluoroalkyl acid contamination of follicular fluid and its consequence for in vitro oocyte developmental competence.
Sci. Total Environ.
PUBLISHED: 06-03-2014
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Perfluoroalkyl acids (PFAAs) have been shown to induce negative effects in laboratory animals and in vitro experiments. Also, PFAAs have been detected in human tissues and body fluids. The ovarian follicle constitutes a fragile micro-environment where interactions between hormones, growth factors, the oocyte and surrounding somatic cells are essential to generate a fully competent oocyte. In vitro experiments suggest that PFAAs can influence this balance, but very scarce in vivo data are available to confirm this assumption. In fact, the potential PFAA-presence in the follicular micro-environment is currently unknown. Therefore, we investigated if PFAAs are present in human follicular fluid and if their presence could be a risk factor for in vivo exposed developing oocytes. Furthermore, we compared the PFAA-distribution within serum and follicular fluid. PFAAs were analyzed by LC/MS in follicular fluid (n=38) and serum (n=20) samples from women undergoing assisted reproductive technologies (ARTs). Statistical models were used to investigate PFAA-distribution in both body fluids, to compare this behavior with the distribution of lipophilic organic pollutants and to explore the relationship between patient characteristics, ART-results and follicular fluid contamination. Perfluorooctane sulfonate (PFOS) was the PFAA found in the highest concentration in follicular fluid [7.5 (0.1-30.4) ng/mL] and serum [7.6 (2.8-12.5) ng/mL]. A new variable, Principal Component 1, representing the overall PFAA-contamination of the follicular fluid samples, was associated with a higher fertilization rate (p<0.05) and a higher proportion of top embryos relative to the amount of retrieved oocytes (p<0.05), after adjusting for age, estradiol-concentration, BMI, male subfertility and the presence of other organic pollutants as explanatory variables. To conclude, overall higher PFAA-contamination in the follicular micro-environment was associated with a higher chance of an oocyte to develop into a high quality embryo. Also, PFAAs have different distribution patterns between serum and follicular fluid compared to the lipophilic organic pollutants. Further research is of course crucial to confirm these new observations.
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Mental health literacy and borderline personality disorder (BPD): what do the public "make" of those with BPD?
Soc Psychiatry Psychiatr Epidemiol
PUBLISHED: 05-29-2014
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This study was part of a programmatic series into mental health literacy, specifically lay people's knowledge of causes, manifestations and cures of Borderline Personality Disorder (BPD). The aim was to determine to what extent non-experts understood BDP and to what extent they held erroneous beliefs about specific aspects of the causes and cures for the disorder METHOD: A convenience sample of 102 participants completed a vignette-identification task that required them to answer open-ended questions about hypothetical people with four psychological problems, one of which was BPD and a 50-item questionnaire divided into three sections about BDP.
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Occurrence of a broad range of legacy and emerging flame retardants in indoor environments in Norway.
Environ. Sci. Technol.
PUBLISHED: 05-23-2014
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This study investigates the occurrence of 37 organohalogen and organophosphate flame retardants (FRs) from Norwegian households (n = 48) and classrooms from two primary schools (n = 6). Around 80% of the targeted FRs were detected in air and dust from the sampling sites. The comparison of settled dust with floor dust revealed no statistical differences between median concentrations of the FRs (n = 12). Decabromodiphenyl ether and tris(2-butoxyethyl) phosphate showed the highest median floor dust concentrations in both environments. In the air samples, the highest concentrations were observed for 2,2',4,4'-tetrabromodiphenyl ether and tris(1-chloro-2-propyl) phosphate. Remarkably, the emerging FR, 4-(1,2-dibromoethyl)-1,2-dibromocyclohexane, abbreviated as TBECH or DBE-DBCH, showed the highest indoor air concentrations reported in the literature (households, 77.9 pg/m(3) and schools, 46.6 pg/m(3)). Good Spearman correlations between the FR concentrations in dust and air (0.36 < R < 0.76) showed that is possible to estimate the concentrations in air from analyzed dust, or vice versa. Sources and pathways of exposure to FRs were assessed for the households. The main findings were that frequent vacuum cleaning resulted in lower FR concentrations in dust and that dermal contact with dust, for both children and mothers, was as important for the intake of organophosphate FRs as dust ingestion.
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Generation of geometrically ordered lipid-based liquid-crystalline nanoparticles using biologically relevant enzymatic processing.
Langmuir
PUBLISHED: 05-09-2014
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High-symmetry lipid nanoparticles with internal bicontinuous cubic phase structure (cubosomes) are prepared from a simple emulsion containing a mixture of a nondigestible lipid (phytantriol) and a digestible short-chained triglyceride using enzymatic lipolysis of the incorporated short-chained triglyceride. The lipolytic products partition away from the nondigestible lipid, resulting in crystallization of the cubic-phase internal structure. Time-resolved small-angle X-ray scattering revealed the kinetics of the disorder-to-order transition, with cryo-transmission electron microscopy showing an absence of liposomes. The new approach offers a new "sideways" method for the generation of lipid-based nanostructured materials that avoids the problems of top-down and bottom-up approaches.
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Analytic thinking reduces belief in conspiracy theories.
Cognition
PUBLISHED: 05-08-2014
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Belief in conspiracy theories has been associated with a range of negative health, civic, and social outcomes, requiring reliable methods of reducing such belief. Thinking dispositions have been highlighted as one possible factor associated with belief in conspiracy theories, but actual relationships have only been infrequently studied. In Study 1, we examined associations between belief in conspiracy theories and a range of measures of thinking dispositions in a British sample (N=990). Results indicated that a stronger belief in conspiracy theories was significantly associated with lower analytic thinking and open-mindedness and greater intuitive thinking. In Studies 2-4, we examined the causational role played by analytic thinking in relation to conspiracist ideation. In Study 2 (N=112), we showed that a verbal fluency task that elicited analytic thinking reduced belief in conspiracy theories. In Study 3 (N=189), we found that an alternative method of eliciting analytic thinking, which related to cognitive disfluency, was effective at reducing conspiracist ideation in a student sample. In Study 4, we replicated the results of Study 3 among a general population sample (N=140) in relation to generic conspiracist ideation and belief in conspiracy theories about the July 7, 2005, bombings in London. Our results highlight the potential utility of supporting attempts to promote analytic thinking as a means of countering the widespread acceptance of conspiracy theories.
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Antimicrobial activity of resveratrol analogues.
Molecules
PUBLISHED: 04-25-2014
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Stilbenes, especially resveratrol and its derivatives, have become famous for their positive effects on a wide range of medical disorders, as indicated by a huge number of published studies. A less investigated area of research is their antimicrobial properties. A series of 13 trans-resveratrol analogues was synthesized via Wittig or Heck reactions, and their antimicrobial activity assessed on two different grapevine pathogens responsible for severe diseases in the vineyard. The entire series, together with resveratrol, was first evaluated on the zoospore mobility and sporulation level of Plasmopara viticola (the oomycete responsible for downy mildew). Stilbenes displayed a spectrum of activity ranging from low to high. Six of them, including the most active ones, were subsequently tested on the development of Botrytis cinerea (fungus responsible for grey mold). The results obtained allowed us to identify the most active stilbenes against both grapevine pathogens, to compare the antimicrobial activity of the evaluated series of stilbenes, and to discuss the relationship between their chemical structure (number and position of methoxy and hydroxy groups) and antimicrobial activity.
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Levels and profile of several classes of organic contaminants in matched indoor dust and serum samples from occupational settings of Pakistan.
Environ. Pollut.
PUBLISHED: 04-18-2014
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Dust ingestion is an important route of human exposure to organic contaminants, especially for flame retardants (FRs) in occupational settings. Several classes of organic contaminants were analyzed in matched dust and serum samples from academics and workers in electronics and clothing stores of Faisalabad, Pakistan. The concentrations of contaminants varied in dust as follow: organophosphate FRs (?PFRs) > novel brominated FRs (?NBFRs) > polybrominated diphenyl ethers (?PBDEs) > organochlorine pesticides (?OCPs) > polychlorinated biphenyls (?PCBs), while, in serum, concentration varied: ?OCPs > bromophenols (?BPs) > ?PCBs > ?HO-PCBs ? ?PBDEs. Two NBFRs, namely 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE) and bis(2-ethylhexyl) tetrabromophthalate (TBPH), were detected in <10% of the serum samples. p,p'-DDE was the major contaminant in serum contributing to ?75% of the total contaminant burden. Levels of Penta-BDE congeners in serum and dust were significantly correlated (r = 0.64, p < 0.01) for the academics, suggesting dust ingestion as an important determinant for their serum levels.
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Hair ethyl glucuronide as a biomarker of alcohol consumption in alcohol-dependent patients: role of gender differences.
Drug Alcohol Depend
PUBLISHED: 04-15-2014
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Ethyl glucuronide (EtG) is a minor alcohol metabolite that accumulates in hair and is proposed as a stable marker for the detection of chronic and excessive alcohol consumption above a cut-off level of 30pg/mg hair. A correlation between drinking behavior and EtG hair concentrations is observed, but large variability exists.
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The influence of the body mass index (BMI) on the volume of distribution of ethanol.
Forensic Sci. Int.
PUBLISHED: 03-26-2014
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The volume of distribution of ethanol was already established in 1930s by Widmark. However, since then the average body composition has changed considerably. The effect of the body mass index (BMI) on the volume of distribution of ethanol was evaluated in this study. Fifty healthy volunteers (23 men and 27 women), with BMI-values between 16.0 and 36.0kg/m(2), were asked to drink a dose of 0.4g ethanol per kilogram body weight after an overnight fast. The ethanol content was measured by a fully validated headspace-GC-FID method. The volume of distribution of ethanol varied between 0.40 and 0.68L/kg for women, and between 0.43 and 0.73L/kg for men. For both sexes, the volume of distribution decreased with increasing BMI. Regression analysis resulted in the following equations: volume of distribution=0.8202-0.0090×BMI for men (r=0.66), and 0.7772-0.0099×BMI for women (r=0.78). Population probability prediction interval limits were also calculated. In view of the current study, fixed values for the volume of distribution of 0.7L/kg and 0.6L/kg for men and women, respectively, often applied in legal blood alcohol calculations, are mainly suited to judge underweight or normal weight people, but not obese persons.
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Human biomonitoring of emerging pollutants through non-invasive matrices: state of the art and future potential.
Anal Bioanal Chem
PUBLISHED: 03-04-2014
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Human biomonitoring (HBM) is a scientific technique that allows us to assess whether and to what extent environmental pollutants enter humans. We review here the current HBM efforts for organophosphate esters, emerging flame retardants, perfluoroalkyl substances, and phthalate esters. Use of some of these chemicals has already been banned or restricted; they are regularly detected in the environment, wildlife, and human matrices. Traditionally, blood and urine collection have been widely used as sampling methods. New non-invasive approaches (e.g., saliva, hair, nails) are emerging as valid alternatives since they offer advantages with respect to sampling, handling, and ethical aspects, while ensuring similar reliability and sensitivity. Nevertheless, the identification of biomarkers of exposure is often difficult because chemicals may be metabolized in the human body. For many of the above-mentioned compounds, the mechanisms of the favorable metabolization pathways have not been unraveled, but research on important metabolites that could be used as biomarkers of exposure is growing. This review summarizes the state of the art regarding human exposure to, (non-invasive) HBM of, and metabolism of major organophosphate esters, emerging flame retardants, perfluoroalkyl substances, and phthalate esters currently detected in the environment.
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Methoxylated PBDEs (MeO-PBDEs), hydroxylated PBDEs (HO-PBDEs) and hydroxylated PCBs (HO-PCBs) in the liver of harbor seals from the northwest Atlantic.
Sci. Total Environ.
PUBLISHED: 03-03-2014
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Metabolites of PCBs and PBDEs are shown to influence the thyroid hormone homeostasis and therefore, could have an influence on the growth of newborn or young animals. We have investigated the occurrence of hydroxylated PCBs (HO-PCBs), hydroxylated PBDEs (HO-PBDEs), and methoxylated PBDEs (MeO-PBDEs) in the liver (48 pups; 6 adults) and blubber (4 pups; 1 adult) of harbor seals (Phoca vitulina concolor) from the northwest Atlantic. The sum of HO-PCBs in the liver ranged from 90 to 22,450 pg/g wet weight (ww) for pups and from 410 to 5290 pg/g ww for adults. Congener 4-HO-CB 107 was predominant in almost all samples regardless of age or gender, except in one adult male. Sum HO-PCB concentrations were highly correlated with the sum of precursor PCBs in the liver of harbor seals (r(2) = 0.79; p<0.0001). Concentrations of sum HO-PBDEs in the liver ranged from 70 to 1850 pg/g ww for pups and from 90 to 230 pg/g ww for adults. HO-PBDEs were also correlated with PBDEs (r(2) = 0.58; p<0.0001). Sum MeO-PBDE concentrations in the liver ranged from 20 to 1460 pg/g ww in pups and from 10 to 270 pg/g ww in adults. HO-PCBs and HO-PBDEs were not detected in the blubber. Levels of MeO-PBDEs in the blubber ranged from 1500 to 4400 pg/g ww. In all blubber samples, 6-MeO-BDE 47 was the predominant MeO-PBDE congener, followed by 2'-MeO-BDE 68 and 5-MeO-BDE 47, respectively. The presence of HO-metabolites in pup liver suggests that young harbor seals may have some, yet limited, metabolic capacity for PCBs and PBDEs, which can lead to an excessive accumulation of these chemicals in the body. Moreover, the presence of HO-PCB and HO-PBDE metabolites may pose an additional stress for young harbor seals due to their influence on the thyroid hormone system and could have consequences for the entire population.
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How to spot a narcissist: Mental health literacy with respect to Narcissistic Personality Disorder.
Personal Ment Health
PUBLISHED: 02-27-2014
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Lay people were asked to read one Depression, one Schizophrenia, and three Narcissistic Personality Disorder (NPD) vignettes. After each, they were asked what they thought the problem was for the individuals concerned and to make various ratings. Half of each of the five vignettes were of male, and the other of female, characters. The results demonstrated that laypeople are less likely to suggest help for, and have more difficulty identifying NPD compared to Depression and Schizophrenia. There were differences in the likeliness to suggest help between all three NPD vignettes and differences in the identification of two NPD vignettes possible due to the length and details in different vignettes. The gender of the person in the vignette had no effect on identification. The participants NPI scores were not correlated with the Narcissism literacy suggesting no relationship between having, and spotting, the disorder. Implications and limitations of the research are considered. Copyright © 2014 John Wiley & Sons, Ltd.
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Polychlorinated biphenyls still pose significant health risks to northwest Atlantic harbor seals.
Sci. Total Environ.
PUBLISHED: 02-26-2014
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Polychlorinated biphenyls (PCBs) have been detected at relatively high concentrations in harbor seals, apex predators in the northwest Atlantic. As part of an ongoing assessment of the effects of PCBs on population health, we analyzed tri- to deca-PCBs in the liver of 56 harbor seals (6 adult males, 50 pups) and in 11 blubber samples (4 adult males, 7 pups) and examined tissue-specific accumulation patterns, biomagnification potential, and toxic implications of current PCB concentrations. Hepatic ?30PCB concentrations (overall mean±standard deviation: 76,860±111,800 ng/g lipid weight, lw) were higher than blubber concentrations (48,180±69,420 ng/g lw). Regional trends were suggestive of fresh PCB inputs from the industrialized, densely populated southern coast of New England versus the rural north. The lack of temporal trends confirmed that tissue concentrations of PCBs have plateaued since the early 1990s. Tissue distribution of PCBs varied significantly by age and, surprisingly by gender among the pups. Principal Component Analysis (PCA) revealed that lighter PCBs are selectively transferred from mother to pup blubber in relation to lipid solubility (log Kow), but heavier PCBs may be efficiently transferred during late lactation from mother to pup liver. Biomagnification factors (BMFs) for ?6PCBs from prey fish to adult male seals ranged from 90 to 547 in the liver and 88 to 532 in the blubber, and suggested that molecular structure and metabolic capacity were more important influences than log Kow on the retention of PCBs. Blubber concentrations of ?30PCBs in 87% of the pups were an order of magnitude higher than recent toxic reference values (TRVs) calculated for ?154PCBs in nursing harbor seals, suggesting that the pups are at risk for PCB-mediated toxicity at a vulnerable stage of development. Given the recurring pattern of epizootics in these seals, the health of the population is of concern.
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The grapevine flagellin receptor VvFLS2 differentially recognizes flagellin-derived epitopes from the endophytic growth-promoting bacterium Burkholderia phytofirmans and plant pathogenic bacteria.
New Phytol.
PUBLISHED: 02-05-2014
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• The role of flagellin perception in the context of plant beneficial bacteria still remains unclear. Here, we characterized the flagellin sensing system flg22-FLAGELLIN SENSING 2 (FLS2) in grapevine, and analyzed the flagellin perception in the interaction with the endophytic plant growth-promoting rhizobacterium (PGPR) Burkholderia phytofirmans. • The functionality of the grapevine FLS2 receptor, VvFLS2, was demonstrated by complementation assays in the Arabidopsis thaliana fls2 mutant, which restored flg22-induced H?O? production and growth inhibition. Using synthetic flg22 peptides from different bacterial origins, we compared recognition specificities between VvFLS2 and AtFLS2. • In grapevine, flg22-triggered immune responses are conserved and led to partial resistance against Botrytis cinerea. Unlike flg22 peptides derived from Pseudomonas aeruginosa or Xanthomonas campestris, flg22 peptide derived from B. phytofirmans triggered only a small oxidative burst, weak and transient defense gene induction and no growth inhibition in grapevine. Although, in Arabidopsis, all the flg22 epitopes exhibited similar biological activities, the expression of VvFLS2 into the fls2 background conferred differential flg22 responses characteristic for grapevine. • These results demonstrate that VvFLS2 differentially recognizes flg22 from different bacteria, and suggest that flagellin from the beneficial PGPR B. phytofirmans has evolved to evade this grapevine immune recognition system.
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Trauma type affects recognition of Post-Traumatic Stress Disorder among online respondents in the UK and Ireland.
J Affect Disord
PUBLISHED: 02-02-2014
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Mental Health Literacy (MHL) predicts help-seeking for mental health difficulties. Public surveys show high recognition of Post-Traumatic Stress Disorder (PTSD) in relation to military contexts, but this has not been investigated with other sources of trauma.
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Relationships between dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like biphenyls (dl-PCBs) congener concentrations in aquatic organisms from Sydney Estuary, Australia and physiology, spatial, seasonality, trophodynamic and life history traits.
Sci. Total Environ.
PUBLISHED: 01-27-2014
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Over the past few decades, there has been considerable interest in hydrophobic persistent organic pollutants (POPs) and their accumulative properties in aquatic organisms. Several factors, such as environmental concentrations (i.e. in sediment) and physiological characteristics of organisms determine species-specific accumulation patterns of POPs in marine animal tissue. The present study investigated factors that govern species-specific accumulation patterns of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like biphenyls (dl-PCBs) in a food web from Sydney Estuary (Australia). The results indicated that physiological characteristics, i.e. lipid %, spatial, i.e. distance from Homebush Bay (point source of POPs) and life history characteristics of the organisms, such as diet and home range, influence PCDD/F and dl-PCB tissue concentrations to a varying degree. For example, PCDD/F tissue concentrations increased with the presence of detritivorous diet, species with limited home range and close proximity to Homebush Bay. On the other hand, lipid %, piscivorous diet and close proximity to Homebush Bay were the main predictors causing increases in dl-PCB tissue levels. Distance from Homebush Bay was the only predictor affecting both PCDD/F and dl-PCB tissue levels at a similar rate, i.e. decreasing tissue concentrations as the distance increases from Homebush Bay.
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Mobilisation of lipophilic pollutants from blubber in northern elephant seal pups (Mirounga angustirostris) during the post-weaning fast.
Environ. Res.
PUBLISHED: 01-24-2014
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Northern elephant seals (NES) (Mirounga angustirostris) from the Año Nuevo State Reserve (CA, USA) were longitudinally sampled during the post-weaning fast in order to study the mobilisation and redistribution of various classes of persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB) between blubber and blood. Inner and outer blubber layers were analysed separately. Organohalogenated compounds were detected in all blubber samples in the decreasing order of their concentrations: p,p'-DDE > PCBs ? HCB > PBDEs. The concentrations of all studied compounds were homogeneously distributed in the blubber layer at early fast, since the concentrations of POPs were statistically not different in the inner and outer layers. With the progression of the fast, the concentrations of PBDEs, PCBs and p,p'-DDE increased more sharply in inner blubber than in outer blubber. As a result, their levels became significantly higher in inner blubber as compared to outer blubber at late fast. The rise of pollutant concentrations in blubber might result from a less efficient mobilisation than triglycerides and/or a reuptake by adipocytes of some of the pollutants released into the circulation. The mobilisation of pollutants from blubber was higher at late fast. An increase of pollutant concentrations was observed in serum between early and late fast. Lower halogenated congeners (i.e. tetra-CBs) were present in higher proportions in serum, whereas the higher halogenated congeners (i.e. hepta-CBs) were mainly found in the inner and outer blubber layers. The transfer ratios of both PBDEs and PCBs from inner blubber to serum decreased with the number of chlorine and bromine atoms. In addition, the distribution of both types of compounds between serum and blubber was strongly influenced by their lipophilic character (logKow values), with more lipophilic compounds being less efficiently released from blubber to serum.
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A Big Five facet analysis of sub-clinical narcissism: understanding boldness in terms of well-known personality traits.
Personal Ment Health
PUBLISHED: 01-18-2014
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This study aimed to examine a Big Five 'bright-side' analysis of a sub-clinical personality disorder, i.e. narcissism. A total of 6957 British adults completed the NEO-PI-R, which measures the Big Five Personality factors at the domain and the facet level, as well as the Hogan Development Survey (HDS), which has a measure of Narcissism called Bold as one of its dysfunctional interpersonal tendencies. Correlation and regression results confirmed many of the associations between the Big Five domains and facets (NEO-PI-R) and sub-clinical narcissism. The Bold (Narcissism) scale from the HDS was the criterion variable in all analyses. Bold individuals are disagreeable extraverts with very low scores on facet Modesty but moderately high scores on Assertiveness, Competence and Achievement Striving. The study confirmed work using different population groups and different measures.
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Biochemical and Structural Characterization of Mycobacterial Aspartyl-tRNA Synthetase AspS, a Promising TB Drug Target.
PLoS ONE
PUBLISHED: 01-01-2014
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The human pathogen Mycobacterium tuberculosis is the causative agent of pulmonary tuberculosis (TB), a disease with high worldwide mortality rates. Current treatment programs are under significant threat from multi-drug and extensively-drug resistant strains of M. tuberculosis, and it is essential to identify new inhibitors and their targets. We generated spontaneous resistant mutants in Mycobacterium bovis BCG in the presence of 10× the minimum inhibitory concentration (MIC) of compound 1, a previously identified potent inhibitor of mycobacterial growth in culture. Whole genome sequencing of two resistant mutants revealed in one case a single nucleotide polymorphism in the gene aspS at 535GAC>535AAC (D179N), while in the second mutant a single nucleotide polymorphism was identified upstream of the aspS promoter region. We probed whole cell target engagement by overexpressing either M. bovis BCG aspS or Mycobacterium smegmatis aspS, which resulted in a ten-fold and greater than ten-fold increase, respectively, of the MIC against compound 1. To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. Finally, to aid hit-to-lead optimization, the crystal structure of apo M. smegmatis AspS was determined to a resolution of 2.4 Å.
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Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays.
Front Plant Sci
PUBLISHED: 01-01-2014
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Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of "PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type" oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as signaling molecules, especially in plant microbe interactions, is also presented. Secondly, the potentialities and limits of foliar sprays of carbohydrates to stimulate plant immunity for crop protection against diseases are discussed, with focus on the roles of the leaf cuticle and phyllosphere microflora.
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Emotional intelligence and the Occupational Personality Questionnaire (OPQ).
Front Psychol
PUBLISHED: 01-01-2014
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This study explores the relationship between the Bar-on EQ-I and the Occupational Personality Questionnaire OPQ32i to determine if there is a link between self- and other-reported Emotional Intelligence and personality traits. Data was obtained from 329 managers working in the IT and Finance sectors and included multi-source (360°) measures of Emotional Intelligence. Results indicated construct overlap and correlations between some elements of Emotional Intelligence and the OPQ32i with a stronger relationship between 360 measures of Emotional Intelligence and personality. On both the self-report measure of EQ-I and the 360 measure the mood scale showed a strongest link with personality factors. Measures of Emotional Intelligence which include a 360 component may thus provide a more useful indicator of an individual's ability to manage their own feelings and those of others.
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Corpus callosum changes in euthymic bipolar affective disorder.
Br J Psychiatry
PUBLISHED: 12-19-2013
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Changes in corpus callosum area and thickness have been reported in bipolar disorder. Imaging and limited neuropathological data suggest possible abnormalities in myelination and/or glial function.
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An investigation of cognitive test performance across conditions of silence, background noise and music as a function of neuroticism.
Anxiety Stress Coping
PUBLISHED: 12-10-2013
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The present study investigates the role of trait neuroticism on cognitive performance under distraction. Seventy participants were given a personality test and then undertook a number of different cognitive tasks in silence, in the presence of popular music and in background noise. It was predicted that performance on a general intelligence test, a test of abstract reasoning, and a mental arithmetic task would be adversely affected by background sounds. It was predicted that neuroticism would be negatively correlated with performance on the mental arithmetic task but only when the individuals were working in the presence of background sound. Stable vs. unstable participants performance on a mental arithmetic task during noise was significantly higher as predicted. The results provided partial support for the hypotheses and are discussed with respect to previous findings in the literature on personality (particularly introversion-extraversion) and distraction on cognitive task performance. Limitations are noted.
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Formation of Highly Organized Nanostructures during the Digestion of Milk.
ACS Nano
PUBLISHED: 12-10-2013
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Natures own emulsion, milk, consists of nutrients such as proteins, vitamins, salts, and milk fat with primarily triglycerides. The digestion of milk fats is the key to the survival of mammal species, yet it is surprising how little we understand this process. The lipase-catalyzed hydrolysis of dietary fats into fatty acids and monoglyceride is essential for efficient absorption of the fat by the enterocytes. Here we report the discovery of highly ordered geometric nanostructures during the digestion of dairy milk. Transitions from normal emulsion through a variety of differently ordered nanostructures were observed using time-resolved small-angle X-ray scattering on a high-intensity synchrotron source and visualized by cryogenic transmission electron microscopy. Water and hydrophilic molecules are transferred into the lipid phase of the milk particle, turning the lipid core gradually into a more hydrophilic environment. The formation of highly ordered lipid particles with substantial internal surface area, particularly in low-bile conditions, may indicate a compensating mechanism for maintenance of lipid absorption under compromised lipolysis conditions.
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The recognition of the personality disorders among young people.
Int J Soc Psychiatry
PUBLISHED: 12-09-2013
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Previous research suggests that mental health literacy regarding the personality disorders is low, with few disorders being recognised.
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Gender, g, gender identity concepts, and self-constructs as predictors of the self-estimated IQ.
J Genet Psychol
PUBLISHED: 12-06-2013
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In all 102 participants completed 2 intelligence tests, a self-estimated domain-masculine (DMIQ) intelligence rating (which is a composite of self-rated mathematical-logical and spatial intelligence), a measure of self-esteem, and of self-control. The aim was to confirm and extend previous findings about the role of general intelligence and gender identity in self-assessed intelligence. It aimed to examine further correlates of the Hubris-Humility Effect that shows men believe they are more intelligent than women. The DMIQ scores were correlated significantly with gender, psychometrically assessed IQ, and masculinity but not self-esteem or self-control. Stepwise regressions indicated that gender and gender role were the strongest predictors of DMIQ accounting for a third of the variance.
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Collagen Fibril Orientation and Tear Strength across Ovine Skins.
J. Agric. Food Chem.
PUBLISHED: 12-03-2013
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Variability of physical properties across hides and skins requires careful consideration when manufacturing goods from leather. Therefore, an understanding of the extent of this variation and its nanostructural basis is useful. Tear strength tests were performed on ovine leather from a grid of 81 positions on skins. Synchrotron small-angle X-ray scattering measurements were made from three positions on the skin, from 26 skins. The X-ray structural measurements are compared with tear strengths of the samples. It is found that the thickness normalized tear strength does not vary greatly between different positions on the skin, in contrast to bovine hides. There is more variation between different skins than within the same skin. The collagen fibril orientation and orientation index, which has previously been shown to be correlated with tear strength, do not vary significantly between the different sampling positions in ovine skins. The collagen fibril orientation varies through the thickness of the skin in a consistent way. The consistency of collagen orientation in ovine leather between different positions on the skin is in marked contrast to bovine hides and informs the use of ovine leather for manufacturing applications.
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Collagen fibril diameter and leather strength.
J. Agric. Food Chem.
PUBLISHED: 11-14-2013
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The main structural component of leather and skin is type I collagen in the form of strong fibrils. Strength is an important property of leather, and the way in which collagen contributes to the strength is not fully understood. Synchrotron-based small angle X-ray scattering (SAXS) is used to measure the collagen fibril diameter of leather from a range of animals, including sheep and cattle, that had a range of tear strengths. SAXS data were fit to a cylinder model. The collagen fibril diameter and tear strength were found to be correlated in bovine leather (r(2) = 0.59; P = 0.009), with stronger leather having thicker fibrils. There was no correlation between orientation index, i.e., fibril alignment, and fibril diameter for this data set. Ovine leather showed no correlation between tear strength and fibril diameter, nor was there a correlation across a selection of other animal leathers. The findings presented here suggest that there may be a different structural motif in skin compared with tendon, particularly ovine skin or leather, in which the diameter of the individual fibrils contributes less to strength than fibril alignment does.
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Dynamics of Organohalogenated Contaminants in Human Serum from Obese Individuals during One Year of Weight Loss Treatment.
Environ. Sci. Technol.
PUBLISHED: 10-10-2013
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We investigated the dynamics of several organohalogenated contaminants (OHCs) and their metabolites in an obese population during weight loss. Serum samples from obese individuals were taken before patients lost weight and after three, six, and twelve months. Samples were also collected from a matched lean control population. Analyzed OHCs were polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (HO-PCBs), pentachlorophenol (PCP), polybrominated diphenyl ethers, and organochlorine pesticides (OCPs). Significantly lower concentrations of major PCBs, their metabolites, and PCP were measured in obese individuals at the initial moment of their enrolling in the project. While dilution differences might be responsible for the lower concentrations in the neutral OHCs, we suggest that a lower CYP-mediated metabolic activity can partially explain the data for the HO-PCBs. Additionally, lower chlorinated substituted PCBs had a higher percentage contribution to the sum PCBs in obese individuals, while higher chlorinated PCBs had a higher contribution for the controls. Increasing serum levels for all OHCs were observed during weight loss. The release from adipose tissue seemed dependent on the octanol-water partition coefficient, since OHCs with higher log Kow values displayed a higher release in serum. This also influenced the HO-PCBs profile after weight loss with lower chlorinated HO-PCBs increasingly gaining importance. Although weight loss is beneficial, it also influences the release of OHCs from adipose tissue and their metabolism. Therefore, the increase in the levels of compounds with endocrine effects might be of concern.
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Lay theories of gender identity disorder.
J Homosex
PUBLISHED: 09-25-2013
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This study examined lay theories regarding gender identity disorder (GID). Pilot interviews were completed with participants (n = 10) regarding their views on possible causes and treatments of GID. Participants (mainly young British people and students; n = 124) then completed a questionnaire that was based on the interviews and a review of the salient literature on lay theories. As hypothesized, participants believed most in biomedical causes and treatments of GID. Factor analysis (with varimax rotation) identified 4 factors in relation to causes of GID: upbringing and personal factors, pregnancy and brain abnormalities, environmental factors, and biomedical causes. Five factors that were identified in relation to the cure/treatment of GID were psychological assistance and personal factors, extreme medical and behavioral changes, alternative therapies, external factors, and medical treatments. The results indicated that participants neither agreed nor strongly disagreed about causes and cures regarding GID, but that these beliefs were logically related. Limitations, particularly of sampling, were considered.
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Specificity determinants for lysine incorporation in Staphylococcus aureus peptidoglycan as revealed by the structure of a MurE enzyme ternary complex.
J. Biol. Chem.
PUBLISHED: 09-24-2013
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Formation of the peptidoglycan stem pentapeptide requires the insertion of both L and D amino acids by the ATP-dependent ligase enzymes MurC, -D, -E, and -F. The stereochemical control of the third position amino acid in the pentapeptide is crucial to maintain the fidelity of later biosynthetic steps contributing to cell morphology, antibiotic resistance, and pathogenesis. Here we determined the x-ray crystal structure of Staphylococcus aureus MurE UDP-N-acetylmuramoyl-L-alanyl-D-glutamate:meso-2,6-diaminopimelate ligase (MurE) (E.C. 6.3.2.7) at 1.8 ? resolution in the presence of ADP and the reaction product, UDP-MurNAc-L-Ala-?-D-Glu-L-Lys. This structure provides for the first time a molecular understanding of how this Gram-positive enzyme discriminates between L-lysine and D,L-diaminopimelic acid, the predominant amino acid that replaces L-lysine in Gram-negative peptidoglycan. Despite the presence of a consensus sequence previously implicated in the selection of the third position residue in the stem pentapeptide in S. aureus MurE, the structure shows that only part of this sequence is involved in the selection of L-lysine. Instead, other parts of the protein contribute substrate-selecting residues, resulting in a lysine-binding pocket based on charge characteristics. Despite the absolute specificity for L-lysine, S. aureus MurE binds this substrate relatively poorly. In vivo analysis and metabolomic data reveal that this is compensated for by high cytoplasmic L-lysine concentrations. Therefore, both metabolic and structural constraints maintain the structural integrity of the staphylococcal peptidoglycan. This study provides a novel focus for S. aureus-directed antimicrobials based on dual targeting of essential amino acid biogenesis and its linkage to cell wall assembly.
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Factors influencing the bioaccumulation of persistent organic pollutants in food webs of the scheldt estuary.
Environ. Sci. Technol.
PUBLISHED: 09-19-2013
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Concentrations of several persistent organic pollutants (POPs: PCBs, PBDEs, OCPs) in aquatic species from the Scheldt estuary were related with factors (body size, lipids, trophic position) possibly influencing their bioaccumulation. Stable nitrogen isotope ratios (?(15)N) were used as a measure for trophic position. A decreasing trend in POP levels toward the sea was observed. For POP concentrations in sediments, this trend could be attributed to a dilution effect from mixing with seawater. However, concentrations in biota more downstream were higher than expected after taking into account the dilution effect, possibly due to differences in bioavailability. Tissue concentrations were correlated with the lipid content in biota, but not with body size. Biomagnification was only significant for some PCB congeners and p,p-DDE at the most marine sampling location (Terneuzen, L1) and for p,p-DDD and BDE 100 at the second sampling location (Bath, L2). A significant decreasing relationship was found for ?-HCH concentrations with increasing ?(15)N at Terneuzen. For Antwerpen (L3), no significant relationships were detected. TMFs ranged from 0.64 for ?-HCH up to 1.60 for PCB 194. These results suggest that biomagnification was more important in the marine part of the estuary, although the presence of multiple carbon sources at the freshwater side might have led to an underestimation of the influence of trophic position.
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Legacy and current-use brominated flame retardants in the Barn Owl.
Sci. Total Environ.
PUBLISHED: 09-17-2013
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The present study investigated the current-use brominated flame retardants (BFRs) tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD), simultaneously with legacy polybrominated diphenyl ethers (PBDEs), in Barn Owls (Tyto alba) collected from two regions with a contrasting degree of urbanisation and vicinity to point sources (Flanders in Belgium versus Normandy in France). Both tissues (muscle, liver, adipose and preen gland) and feathers (primary, tail and body feathers) showed elevated HBCD concentrations in Flanders, close to Europes sole HBCD production plant in the Netherlands, and identified Normandy as a historical source region for PBDEs. In sharp contrast, the reactive BFR TBBPA bioaccumulated poorly (2.3%) in tissue samples, but was present in 96% of all body feather samples (0.36-7.07ngg(-1)dw), equally in both regions. PBDE concentrations in tissues (7.46-903ngg(-1)lw) were considerably lower in the investigated Flemish Barn Owls, collected in 2008/2009, compared to specimens collected in 2003/2004 (46-11,000ngg(-1)lw), possibly suggesting the effectiveness of the 2004 European ban of Penta- and Octa-BDE mixtures. Feathers showed a similar trend and additionally exhibited HBCD concentrations (0.02-333ngg(-1)dw) surpassing those of PBDEs (0.50-10.4ngg(-1)dw). While body feathers were a reliable matrix to predict both internal PBDE (0.21?R(2)?0.67) and HBCD body burdens (0.20?R(2)?0.37), the suitability of primary and tail feathers appeared to be confounded by external contamination and moult. In conclusion, the present study clearly showed that the reactive versus additive use of BFRs results in contrasting exposure scenarios in a species higher up the food chain, and therefore may have profound implications for environmental health. In addition, the presented results extend the promising use of feathers as a non-destructive sampling strategy for current-use BFRs, and show that birds of prey are valid early-warning systems for environmental contamination.
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Gender and gender role differences in self- and other-estimates of multiple intelligences.
J Soc Psychol
PUBLISHED: 08-20-2013
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This study examined participant gender and gender role differences in estimates of multiple intelligences for self, partner, and various hypothetical, stereotypical, and counter-stereotypical target persons. A general population sample of 261 British participants completed one of four questionnaires that required them to estimate their own and others multiple intelligences and personality traits. Males estimated their general IQ slightly, but mathematic IQ significantly higher than females, who rated their social and emotional intelligence higher than males. Masculine individuals awarded themselves somewhat higher verbal and practical IQ scores than did female participants. Both participant gender and gender role differences in IQ estimates were found, with gender effects stronger in cognitive and gender role than in "personal" ability estimates. There was a significant effect of gender role on hypothetical persons intelligence evaluations, with masculine targets receiving significantly higher intelligence estimates compared to feminine targets. More intelligent hypothetical figures were judged as more masculine and less feminine than less intelligent ones.
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Adenosine tetraphosphoadenosine drives a continuous ATP-release assay for aminoacyl-tRNA synthetases and other adenylate-forming enzymes.
ACS Chem. Biol.
PUBLISHED: 08-13-2013
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Aminoacyl-tRNA synthetases are essential for the correct linkage of amino acids to cognate tRNAs to maintain the fidelity of protein synthesis. Tractable, continuous assays are valuable for characterizing the functions of synthetases and for their exploitation as drug targets. We have exploited the unexplored ability of these enzymes to consume adenosine tetraphosphoadenosine (diadenosine 5,5? P(1) P(4) tetraphosphate; Ap4A) and produce ATP to develop such an assay. We have used this assay to probe the stereoselectivity of isoleucyl-tRNA(Ile) and Valyl-tRNA(Val) synthetases and the impact of tRNA on editing by isoleucyl-tRNA(Ile) synthetase (IleRS) and to identify analogues of intermediates of these enzymes that might allow targeting of multiple synthetases. We further report the utility of Ap4A-based assays for identification of synthetase inhibitors with nanomolar to millimolar affinities. Finally, we demonstrate the broad application of Ap4A utilization with a continuous Ap4A-driven RNA ligase assay.
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Study protocol for the randomised controlled trial: Antiglucocorticoid augmentation of anti-Depressants in Depression (The ADD Study).
BMC Psychiatry
PUBLISHED: 06-22-2013
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Some patients with depression do not respond to first and second line conventional antidepressants and are therefore characterised as suffering from treatment refractory depression (TRD). On-going psychosocial stress and dysfunction of the hypothalamic-pituitary-adrenal axis are both associated with an attenuated clinical response to antidepressants. Preclinical data shows that co-administration of corticosteroids leads to a reduction in the ability of selective serotonin reuptake inhibitors to increase forebrain 5-hydroxytryptamine, while co-administration of antiglucocorticoids has the opposite effect. A Cochrane review suggests that antiglucocorticoid augmentation of antidepressants may be effective in treating TRD and includes a pilot study of the cortisol synthesis inhibitor, metyrapone. The Antiglucocorticoid augmentation of anti-Depressants in Depression (The ADD Study) is a multicentre randomised placebo controlled trial of metyrapone augmentation of serotonergic antidepressants in a large population of patients with TRD in the UK National Health Service.Methods/design: Patients with moderate to severe treatment refractory Major Depression aged 18 to 65 will be randomised to metyrapone 500 mg twice daily or placebo for three weeks, in addition to on-going conventional serotonergic antidepressants. The primary outcome will be improvement in Montgomery-Asberg Depression Rating Scale score five weeks after randomisation (i.e. two weeks after trial medication discontinuation). Secondary outcomes will include the degree of persistence of treatment effect for up to 6 months, improvements in quality of life and also safety and tolerability of metyrapone. The ADD Study will also include a range of sub-studies investigating the potential mechanism of action of metyrapone.
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First insights in the metabolism of phosphate flame retardants and plasticizers using human liver fractions.
Toxicol. Lett.
PUBLISHED: 06-12-2013
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Phosphate flame retardants and plasticizers (PFRs) are additives used in a wide range of polymers. Important representatives, such as tris(2-butoxyethyl) phosphate (TBOEP), triphenyl phosphate (TPHP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), have been found in the indoor environment at high levels. Biotransformation of these PFRs needs to be investigated because it can be a major determinant of their bioavailability and toxicity in humans. TBOEP, TPHP, TCEP, TCIPP and TDCIPP were incubated with human liver S9 fraction and microsomes. Supernatants were analyzed using a liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometer. Chromatograms were scanned for the presence of Phase-I and Phase-II metabolites and tentatively identified based on mass accuracy of the molecular formula, isotopic pattern, and MS/MS spectra. The two major metabolites of TBOEP were products of O-dealkylation and of hydroxylation, respectively. TPHP was mainly transformed to its diester metabolite by O-dearylation and to a hydroxylated metabolite. TCEP was poorly metabolized into its diester and a product of oxidative dehalogenation. The major metabolite of TCIPP was a product of oxidative dehalogenation. TDCIPP was mainly transformed into its diester and a glutathione S-conjugate. The metabolites identified in the present study are candidate biomarkers for future human biomonitoring studies.
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Hair ethyl glucuronide levels as a marker for alcohol use and abuse: A review of the current state of the art.
Drug Alcohol Depend
PUBLISHED: 05-27-2013
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Ethyl glucuronide (EtG) is a minor alcohol metabolite that has been proposed as a stable marker in hair to detect and quantify alcohol consumption over long time periods.
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Image analysis methods for assessment of H2O2 production and Plasmopara viticola development in grapevine leaves: application to the evaluation of resistance to downy mildew.
J. Microbiol. Methods
PUBLISHED: 05-23-2013
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The grapevine downy mildew (Plasmopara viticola) provokes severe damages and destroys the harvest in the absence of an effective protection. Numerous fungicide treatments are thus generally necessary. To promote a sustainable production, alternative strategies of protection including new antifungal molecules, resistant genotypes or elicitor-induced resistance are under trial. To evaluate the relevance of these strategies, resistance tests are required. In this context, three image analysis methods were developed to read the results of tests performed to assess P. viticola sporulation and mycelial development, and H(2)O(2) production in leaves. They have been validated using elicitors of plant defenses. These methods are reliable, innovative, rapid, and their modular concept allows their further adaptation to other host-pathogen systems.
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Controlling nanostructure and lattice parameter of the inverse bicontinuous cubic phases in functionalised phytantriol dispersions.
J Colloid Interface Sci
PUBLISHED: 05-15-2013
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The preparation and phase behavior of dispersed liquid crystalline particles comprised of phytantriol and various functionalised lipids are reported. These inverse bicontinuous cubic phase colloidal dispersions have been sterically stabilized with a triblock copolymer, Pluronic F127. The influence of added negatively charged amphiphiles oleic acid and sodium dodecylsulfate, the positively charged hexadecyltrimethylammonium bromide, and monoolein a neutral amphiphile, on phase behavior and cubic phase structure was examined by synchrotron small angle X-ray scattering (SAXS). Functionality was also introduced through ligand specific lipids monosialoganglioside-GM1 and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[biotinyl(polyethylene glycol)-2000]. SAXS measurements showed that all of the additives affected the long-range order of the inverse cubic phase observed through either phase behavior changes or alteration in lattice parameter.
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Insulin Resistance and Environmental Pollutants: Experimental Evidence and Future Perspectives.
Environ. Health Perspect.
PUBLISHED: 05-14-2013
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Background: The metabolic disruptor hypothesis postulates that environmental pollutants may be risk factors for metabolic diseases. Because insulin resistance is involved in most metabolic diseases and current health care prevention programs predominantly target insulin resistance or risk factors thereof, a critical analysis of the role of pollutants in insulin resistance might be important for future management of metabolic diseases.Objectives: We aimed to critically review the available information linking pollutant exposure to insulin resistance and to open the discussion on future perspectives for metabolic disruptor identification and prioritization strategies.Methods: We searched PubMed and Web of Science for experimental studies reporting on linkages between environmental pollutants and insulin resistance and identified a total of 23 studies as the prime literature.Discussion: Recent studies specifically designed to investigate the effect of pollutants on insulin sensitivity show a potential causation of insulin resistance. Based on these studies, a summary of viable test systems and end points can be composed, allowing insight into what is missing and what is needed to create a standardized insulin resistance toxicity testing strategy.Conclusions: It is clear that current research predominantly relies on top-down identification of insulin resistance-inducing metabolic disruptors and that the development of dedicated in vitro or ex vivo screens to allow animal sparing and time- and cost-effective bottom-up screening is a major future research need.Citation: Hectors TL, Vanparys C, Van Gaal LF, Jorens PG, Covaci A, Blust R. 2013. Insulin resistance and environmental pollutants: experimental evidence and future perspectives. Environ Health Perspect 121:1273-1281;?http://dx.doi.org/10.1289/ehp.1307082.
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Mental health literacy and obsessive-compulsive personality disorder.
Psychiatry Res
PUBLISHED: 05-07-2013
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An opportunistic sample of 342 participants completed a vignette identification task that required them to name the possible psychological problem of an individual described in vignettes describing people with depression, schizophrenia, OCD and OCPD. Participants rated the degree to which they believed the individual experienced distress, they felt sympathetic towards the described individual, and the degree to which they believed the individual was well-adjusted in the community. There were very low recognition rates of OCPD, with participants more likely to identify depression, schizophrenia and OCD. Analysis of distress, sympathy and adjustment ratings also revealed significant differences between the disorders. The findings highlight the necessity of greater mental health awareness and the importance of psycho-education in order to increase successful treatment seeking of OCPD patients.
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Identifying depression and schizophrenia using vignettes: a methodological note.
Psychiatry Res
PUBLISHED: 04-29-2013
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The aim of this study was to assess lay peoples ability to identify depression and schizophrenia from well established vignettes using hypothetical patients of both sexes. In all 122 participants answered a questionnaire, consisting of six vignette case studies describing psychological symptoms; three each associated with depression and schizophrenia. They answered three questions: what is the persons main problem; how could they be best helped; what would you do to help? Overall, depression was more often correctly identified compared to schizophrenia. The gender of the participant and the individual presented in the vignette did have an effect on the vignette identification task. Limitations and implications of these results and the use of vignette methodology were discussed.
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Fluorous protic ionic liquids exhibit discrete segregated nano-scale solvent domains and form new populations of nano-scale objects upon primary alcohol addition.
Phys Chem Chem Phys
PUBLISHED: 04-15-2013
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Fluorous protic ionic liquids (FPILS) containing a perfluorinated anion and hydrocarbon cation have been observed to segregate into nano-scale fluorocarbon, hydrocarbon and polar domains. The solubility and interactions of ethanol and butanol in a series of FPILs has been investigated by synchrotron source small and wide angle X-ray scattering. Nano-scale objects were found to be present within the binary solutions from low concentrations of FPILs in alcohols to around 40 to 80 wt% FPIL. The FPILs retain their fluorocarbon, hydrocarbon and polar domains in binary mixtures with alcohols in addition to the formation of nano-scale alcohol associated objects. For comparison, the influence of alcohols on the nano-scale segregation of analogous protic ionic liquids (PILs) which contained hydrocarbon anions in place of the perfluorinated anions was also investigated. The ethanol and butanol were miscible with the PILs across the full concentration range, with no evidence for the formation of analogous nano-scale objects. The FPILs are prospective solvents which may enable simultaneous solubility of fluorocarbon, hydrocarbon and polar species.
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Lifetime PCB 153 bioaccumulation and pharmacokinetics in pilot whales: Bayesian population PBPK modeling and Markov chain Monte Carlo simulations.
Chemosphere
PUBLISHED: 03-21-2013
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Physiologically based pharmacokinetic (PBPK) models for wild animal populations such as marine mammals typically have a high degree of model uncertainty and variability due to the scarcity of information and the embryonic nature of this field. Parameters values used in marine mammals models are usually taken from other mammalian species (e.g. rats or mice) and might not be entirely suitable to properly explain the kinetics of pollutants in marine mammals. Therefore, several parameters for a PBPK model for the bioaccumulation and pharmacokinetics of PCB 153 in long-finned pilot whales were estimated in the present study using the Bayesian approach executed with Markov chain Monte Carlo (MCMC) simulations. This method uses prior information of the parameters, either from the literature or from previous model runs. The advantage is that this method uses such prior parameters to calculate probability distributions to determine posterior values that best explain the field observations. Those field observations or datasets were PCB 153 concentrations in blubber of long-finned pilot whales from Sandy Cape and Stanley, Tasmania, Australia. The model predictions showed an overall decrease in PCB 153 levels in blubber over the lifetime of the pilot whales. All parameters from the Sandy Cape model were updated using the Stanley dataset, except for the concentration of PCB 153 in the milk. The model presented here is a promising and preliminary start to PBPK modeling in long-finned pilot whales that would provide a basis for non-invasive studies in these protected marine mammals.
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Health and educational performance among young migrants.
Int J Adolesc Med Health
PUBLISHED: 03-01-2013
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This study is a part replication of an earlier study by on health efficacy, educational attainment and well-being among 30 nations. It includes, however, data from these nations, as well as the latest Pisa results and update socioeconomic data and sociological variables which include divorce rate, number of persons/household, employment rates, and measures of physical and mental health (including new scales of well-being, e.g., mental health index, life satisfaction, suicide rates). More importantly, it includes measures of migrant rates among children and adults in each country, the focus of attention of this article. New material on health and educational expenditure are provided.
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Structural and mechanistic studies of the orf12 gene product from the clavulanic acid biosynthesis pathway.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 02-22-2013
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Structural and biochemical studies of the orf12 gene product (ORF12) from the clavulanic acid (CA) biosynthesis gene cluster are described. Sequence and crystallographic analyses reveal two domains: a C-terminal penicillin-binding protein (PBP)/?-lactamase-type fold with highest structural similarity to the class A ?-lactamases fused to an N-terminal domain with a fold similar to steroid isomerases and polyketide cyclases. The C-terminal domain of ORF12 did not show ?-lactamase or PBP activity for the substrates tested, but did show low-level esterase activity towards 3-O-acetyl cephalosporins and a thioester substrate. Mutagenesis studies imply that Ser173, which is present in a conserved SXXK motif, acts as a nucleophile in catalysis, consistent with studies of related esterases, ?-lactamases and D-Ala carboxypeptidases. Structures of wild-type ORF12 and of catalytic residue variants were obtained in complex with and in the absence of clavulanic acid. The role of ORF12 in clavulanic acid biosynthesis is unknown, but it may be involved in the epimerization of (3S,5S)-clavaminic acid to (3R,5R)-clavulanic acid.
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Periventricular white matter integrity and cortisol levels in healthy controls and in euthymic patients with bipolar disorder: an exploratory analysis.
J Affect Disord
PUBLISHED: 02-09-2013
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Bipolar disorder is associated with both white matter abnormalities and hypothalamo-pituitary-adrenal axis dysfunction. In a post-hoc analysis of diffusion tensor data, the relationship between cortisol levels and white matter structural integrity was explored in healthy controls and in euthymic patients with bipolar disorder.
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Relationships between in vitro lymphoproliferative responses and levels of contaminants in blood of free-ranging adult harbour seals (Phoca vitulina) from the North Sea.
Aquat. Toxicol.
PUBLISHED: 01-22-2013
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In vitro culture of peripheral blood leucocytes (PBLs) is currently used in toxicological studies of marine mammals. However, blood cells of wild individuals are exposed in vivo to environmental contaminants before being isolated and exposed to contaminants in vitro. The aim of this study was to highlight potential relationships between blood contaminant levels and in vitro peripheral blood lymphocyte proliferation in free-ranging adult harbour seals (Phoca vitulina) from the North Sea. Blood samples of 18 individuals were analyzed for trace elements (Fe, Zn, Se, Cu, Hg, Pb, Cd) and persistent organic contaminants and metabolites (?PCBs, ?HO-PCBs, ?PBDEs, 2-MeO-BDE68 and 6-MeO-BDE47, ?DDXs, hexachlorobenzene, oxychlordane, trans-nonachlor, pentachlorophenol and tribromoanisole). The same samples were used to determine the haematology profiles, cell numbers and viability, as well as the in vitro ConA-induced lymphocyte proliferation expressed as a stimulation index (SI). Correlation tests (Bravais-Pearson) and Principal Component Analysis with multiple regression revealed no statistically significant relationship between the lymphocyte SI and the contaminants studied. However, the number of lymphocytes per millilitre of whole blood appeared to be negatively correlated to pentachlorophenol (r=-0.63, p=0.005). In adult harbour seals, the interindividual variations of in vitro lymphocyte proliferation did not appear to be directly linked to pollutant levels present in the blood, and it is likely that other factors such as age, life history, or physiological parameters have an influence. In a general manner, experiments with in vitro immune cell cultures of wild marine mammals should be designed so as to minimize confounding factors in which case they remain a valuable tool to study pollutant effects in vitro.
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Structural Aspects of Digestion of Medium Chain Triglycerides Studied in Real Time Using sSAXS and Cryo-TEM.
Pharm. Res.
PUBLISHED: 01-22-2013
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The purpose of this study was to investigate the colloidal structures formed on digestion of medium chain triglyceride (MCT) with a specific objective of identifying and characterizing a previously reported vesicular phase, which has been linked to supersaturation and anomalous digestion kinetics, and to evaluate the influence of lipid mass and enzyme inhibition on self assembled structure.
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Collagen orientation and leather strength for selected mammals.
J. Agric. Food Chem.
PUBLISHED: 01-17-2013
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Collagen is the main structural component of leather, skin, and some other applications such as medical scaffolds. All of these materials have a mechanical function, so the manner in which collagen provides them with their strength is of fundamental importance and was investigated here. This study shows that the tear strength of leather across seven species of mammals depends on the degree to which collagen fibrils are aligned in the plane of the tissue. Tear-resistant material has the fibrils contained within parallel planes with little crossover between the top and bottom surfaces. The fibril orientation is observed using small-angle X-ray scattering in leather, produced from skin, with tear strengths (normalized for thickness) of 20-110 N/mm. The orientation index, 0.420-0.633, is linearly related to tear strength such that greater alignment within the plane of the tissue results in stronger material. The statistical confidence and diversity of animals suggest that this is a fundamental determinant of strength in tissue. This insight is valuable in understanding the performance of leather and skin in biological and industrial applications.
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Personality traits, education, physical exercise, and childhood neurological function as independent predictors of adult obesity.
PLoS ONE
PUBLISHED: 01-01-2013
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To investigate whether personality traits, education, physical exercise, parental socio-economic conditions, and childhood neurological function are independently associated with obesity in 50 year old adults in a longitudinal birth cohort study.
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Correlates of adult binge drinking: evidence from a british cohort.
PLoS ONE
PUBLISHED: 01-01-2013
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To investigate whether parental social class and cognitive ability in childhood, as well as social and psychological factors, particularly personality traits, are independently associated with binge drinking in 50 year old adults assessed in a longitudinal birth cohort study.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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