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Find video protocols related to scientific articles indexed in Pubmed.
Effectiveness of a Dental Care Intervention in the Prevention of Lower Respiratory Tract Nosocomial Infections among Intensive Care Patients: A Randomized Clinical Trial.
Infect Control Hosp Epidemiol
PUBLISHED: 10-02-2014
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Objective.?To evaluate whether dental treatment may enhance oral antisepsis, thus preventing more effectively lower respiratory tract infections (LRTIs) among critically ill patients. Design.?Observer-blind randomized clinical trial. Setting.?General intensive care unit (ICU) for adult patients. Patients.?We analyzed data from 254 adult patients who stayed for at least 48 hours in the ICU. Intervention.?Patients were randomized by means of rolling dice. The experimental group (n = 127) had access to dental care provided by a dental surgeon, 4-5 times a week. Besides routine oral hygiene, care also included teeth brushing, tongue scraping, removal of calculus, atraumatic restorative treatment of caries, and tooth extraction. The control group (n = 127) had access to routine oral hygiene only, which included the use of chlorhexidine as a mouth rinse, which was performed by the ICU nurse staff. Results.?The primary study outcome was the LRTI incidence, which was 8.7% in the experimental group and 18.1% in the control group (adjusted relative risk [RR], 0.44 [95% confidence interval (CI), 0.20-0.96]; P = .04). Ventilator-associated pneumonia rates per 1,000 ventilator-days were 16.5 (95% CI, 9.8-29.5) in the control group and 7.6 (95% CI, 3.3-15.0) in the experimental group (P < .05). Mortality rates were similar between both study groups: 31.5% in the control group versus 29.1% in the experimental group (adjusted RR, 0.93 [95% CI, 0.52-1.65]; P = .796). No severe adverse events related to oral care were observed during the study. Conclusion.?Dental treatment was safe and effective in the prevention of LRTI among critically ill patients who were expected to stay at least 48 hours in the ICU. Trial registration.?Brazilian Clinical Trials Registry, affiliated with the World Health Organization's International Clinical Trial Registry Platform: U1111-1152-2671.
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Serological diagnosis of paracoccidioidomycosis: high rate of inter-laboratorial variability among medical mycology reference centers.
PLoS Negl Trop Dis
PUBLISHED: 09-01-2014
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Serological tests have long been established as rapid, simple and inexpensive tools for the diagnosis and follow-up of PCM. However, different protocols and antigen preparations are used and the few attempts to standardize the routine serological methods have not succeeded.
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Dietary squalene increases high density lipoprotein-cholesterol and paraoxonase 1 and decreases oxidative stress in mice.
PLoS ONE
PUBLISHED: 08-12-2014
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Squalene, the main hydrocarbon in the unsaponifiable fraction of virgin olive oil, is involved in cholesterol synthesis and it has been reported to own antiatherosclerotic and antiesteatosic effects. However, the squalene's role on lipid plasma parameters and the influence of genotype on this effect need to be addressed.
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Discovering mechanistic insights by application of tandem ultrafast multidimensional NMR techniques.
J. Org. Chem.
PUBLISHED: 08-12-2014
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Ultrafast multidimensional NMR acquisition techniques have shown promising capabilities in studies of dynamic systems in real time. The method's characteristics have permitted the focus to be on the mechanistic details of organic reactions. The tandem UF-TOCSY/HMBC sequence applied here combines both homonuclear and heteronuclear details and therefore provides complete information about the evolution of a dynamic reaction in real time. The methodology will be applied to find an explanation of the low reactivity of alicyclic ketones such as cyclohexanone in reactions with triflic anhydride and aliphatic nitriles, which leads to bicyclic pyrimidines.
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Results for a series of 697 arteriovenous malformations treated by gamma knife: influence of angiographic features on the obliteration rate.
Neurosurgery
PUBLISHED: 07-23-2014
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Stereotactic radiosurgery (RS) is an effective tool in treating brain arteriovenous malformations (AVMs). Careful study of AVM angiographic characteristics may improve results.
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Chalcones as positive allosteric modulators of ?7 nicotinic acetylcholine receptors: a new target for a privileged structure.
Eur J Med Chem
PUBLISHED: 07-22-2014
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The ?7 acetylcholine nicotine receptor is a ligand-gated ion channel that is involved in cognition disorders, schizophrenia, pain and inflammation among other diseases. Therefore, the development of new agents that target this receptor has great significance. Positive allosteric modulators might be advantageous, since they facilitate receptor responses without directly interacting with the agonist binding site. Here we report the search for and further design of new positive allosteric modulators having the relatively simple chalcone structure. From the natural product isoliquiritigenin as starting point, chalcones substituted with hydroxyl groups at defined locations were identified as optimal and specific promoters of ?7 nicotinic function. The most potent compound (2,4,2',5'-tetrahydroxychalcone, 111) was further characterized showing its potential as neuroprotective, analgesic and cognitive enhancer, opening the way for future developments around the chalcone structure.
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One-pot synthesis of 1,3,5-triazine derivatives via controlled cross-cyclotrimerization of nitriles: a mechanism approach.
J. Org. Chem.
PUBLISHED: 07-18-2014
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The reaction of equimolecular amounts of a nitrile and triflic anhydride or triflic acid at low temperature produces an intermediate nitrilium salt that subsequently reacts with 2 equiv of a different nitrile at higher temperature to form 2,4-disusbstituted-6-substituted 1,3,5-triazines in moderate to good yields. This synthetic procedure has also been applied to the preparation of a 1,3,5-triazine having three different substituents. The results are explained in terms of a mechanism based on the relative stability of the intermediate nitrilium salts that are formed through a reversible pathway. The formation of a substituted isoquinoline using benzyl cyanide as the second nitrile supports the postulated mechanism as well as the structure of derivatives of the proposed intermediate when the reaction is carried out in the presence of different nucleophiles other than nitriles. Theoretical calculations and the monitoring of the reaction using (1)H and (13)C NMR spectroscopy are in agreement with the proposed mechanism pathway.
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Jugulotympanic paragangliomas treated with Gamma Knife radiosurgery: a single-center review of 58 cases.
J. Neurosurg.
PUBLISHED: 06-13-2014
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Object Jugulotympanic paragangliomas (JTPs) are rare benign tumors whose surgical treatment is usually associated with partial resection of the lesion, high morbidity, and even death. Gamma Knife radiosurgery (GKRS) has been reported as a useful treatment option. The goal of this retrospective study is to analyze the role of GKRS in tumor volume control and clinical outcomes of these patients. Methods A total of 75 patients with JTPs were treated with GKRS at the authors' center from 1995 to 2012. The authors analyzed those treated during this period to allow for a minimal observation time of 2 years. The MR images and clinical reports of these patients were reviewed to assess clinical and volumetric outcomes of the tumors. The radiological and clinical assessments, along with a group of prognostic factors measured, were analyzed using descriptive methods. The time to volumetric and clinical progression was analyzed using the Kaplan-Meier method. Prognostic factors were identified using log-rank statistics and multivariate Cox regression models. Results The mean follow-up was 86.4 months. The authors observed volumetric tumor control in 94.8% of cases. In 67.2% of cases, tumor volume decreased by a mean of 40.1% from the original size. Of patients with previous tinnitus, 54% reported complete recovery. Improvement of other symptoms was observed in 34.5% of cases. Overall, clinical control was achieved in 91.4% of cases. Previous embolization and familial history of paraganglioma were selected as significant prognostic factors for volumetric response to GKRS treatment in the univariate analysis. In multivariate analysis, no factors were significantly correlated with progression-free survival. No patient died of side effects related to GKRS treatment or tumor progression. Conclusions Gamma Knife radiosurgery is an effective, safe, and efficient therapeutic option for the treatment of these tumors as a first-line treatment or in conjunction with traditional surgery, endovascular treatment, or conventional fractionated radiotherapy.
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Expansion and evolution of a virulent, extensively drug-resistant (polymyxin B-resistant), QnrS1-, CTX-M-2-, and KPC-2-producing Klebsiella pneumoniae ST11 international high-risk clone.
J. Clin. Microbiol.
PUBLISHED: 05-07-2014
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In this study, we report the early expansion, evolution, and characterization of a multiresistant Klebsiella pneumoniae clone that was isolated with increasing frequency from inpatients in a tertiary-care university hospital in Brazil. Seven carbapenem- and quinolone-resistant and polymyxin B-susceptible or -resistant K. pneumoniae isolates isolated between December 2012 and February 2013 were investigated. Beta-lactamase- and plasmid-mediated quinolone resistance (PMQR)-encoding genes and the genetic environment were investigated using PCR, sequencing, and restriction fragment length polymorphism (RFLP). Clonal relatedness was established using XbaI-pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and phylogenetic group characterization. Plasmid analyses included PCR-based replicon typing (PBRT) and hybridization of the S1-PFGE product, plasmid MLST, and conjugation experiments. Virulence potential was assessed by PCR by searching for 10 virulence factor-encoding genes (ureA, fimH, kfuBC, uge, wabG, magA, mrkD, allS, rmpA, and cf29a) and by phenotypic tests to analyze the hypermucoviscous phenotype. The genetic context of a multidrug-resistant and extensively drug-resistant K. pneumoniae ST11-KpI clone harboring IncFIIk-Tn4401a-blaKPC-2, qnrS1, and blaCTX-M-2 was found. Moreover, three isolates displayed high resistance to polymyxin B (MICs = 32, 32, and 128 mg/liter) as well as mucous and hypermucoviscous phenotypes. These bacteria also harbored ureA, fimH, uge, wabG, and mrkD, which code for virulence factors associated with binding, biofilm formation, and the ability to colonize and escape from phagocytosis. Our study describes the association of important coresistance and virulence factors in the K. pneumoniae ST11 international high-risk clone, which makes this pathogen successful at infections and points to the quick expansion and evolution of this multiresistant and virulent clone, leading to a pandrug-resistant phenotype and persistent bacteria in a Brazilian hospital.
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Direct inversion methods for spectral amplitude modulation of femtosecond pulses.
Rev Sci Instrum
PUBLISHED: 05-03-2014
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In the present work, we applied an amplitude-spatial light modulator to shape the spectral amplitude of femtosecond pulses in a single step, without an iterative algorithm, by using an inversion method defined as the generalized retardance function. Additionally, we also present a single step method to shape the intensity profile defined as the influence matrix. Numerical and experimental results are presented for both methods.
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De novo designed library of linear helical peptides: an exploratory tool in the discovery of protein-protein interaction modulators.
ACS Comb Sci
PUBLISHED: 04-22-2014
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Protein-protein interactions (PPIs) have emerged as important targets for pharmaceutical intervention because of their essential role in numerous physiological and pathological processes, but screening efforts using small-molecules have led to very low hit rates. Linear peptides could represent a quick and effective approach to discover initial PPI hits, particularly if they have inherent ability to adopt specific peptide secondary structures. Here, we address this hypothesis through a linear helical peptide library, composed of four sublibraries, which was designed by theoretical predictions of helicity (Agadir software). The 13-mer peptides of this collection fixes either a combination of three aromatic or two aromatic and one aliphatic residues on one face of the helix (Ac-SSEEX(5)ARNX(9)AAX(12)N-NH2), since these are structural features quite common at PPIs interfaces. The 81 designed peptides were conveniently synthesized by parallel solid-phase methodologies, and the tendency of some representative library components to adopt the intended secondary structure was corroborated through CD and NMR experiments. As proof of concept in the search for PPI modulators, the usefulness of this library was verified on the widely studied p53-MDM2 interaction and on the communication between VEGF and its receptor Flt-1, two PPIs for which a hydrophobic ?-helix is essential for the interaction. We have demonstrated here that, in both cases, selected peptides from the library, containing the right hydrophobic sequence of the hot-spot in one of the protein partners, are able to interact with the complementary protein. Moreover, we have discover some new, quite potent inhibitors of the VEGF-Flt-1 interaction, just by replacing one of the aromatic residues of the initial F(5)Y(9)Y(12) peptide by W, in agreement with previous results on related antiangiogenic peptides. Finally, the HTS evaluation of the full collection on thermoTRPs has led to a few antagonists of TRPV1 and TRPA1 channels, which open new avenues on the way to innovative modulators of these channels.
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Dumbbell-type fullerene-steroid hybrids: a join experimental and theoretical investigation for conformational, configurational, and circular dichroism assignments.
J. Org. Chem.
PUBLISHED: 04-04-2014
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New [60]fullerene-steroid conjugates (4-6) have been synthesized by 1,3-dipolar cycloaddition and Bingel-Hirsch cyclopropanation reactions from suitably functionalized epiandrosterone and [60]fullerene. Since a new stereocenter is created in the formation of the Prato monoaduct, two different diastereomers were isolated by HPLC (4, 5) whose absolute configurations were assigned according to the highly reliable "sector rule" on fullerenes. A further reaction of the malonate-containing diastereomer 5 with a second C60 molecule has afforded dumbbell fullerene 6 in which the two fullerene units are covalently connected through an epiandrosterone moiety. The new compounds have been spectroscopically characterized and their redox potentials, determined by cyclic voltametry, reveal three reversible reduction waves for hybrids 4 and 5, whereas these signals are split in dumbbell 6. Theoretical calculations at semiempirical (AM1) and single point B3LYP/6-31G(d) levels have predicted the most stable conformations for the hybrid compounds (4-6), showing the importance of the chlorine atom on the D ring of the steroid. Furthermore, TDDFT calculations have allowed assignments of the experimentally determined circular dichroism (CD) of the [60]fullerene-steroid hybrids based on the sign and position of the Cotton effects, despite the exceptionally large systems under study.
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Extra virgin olive oil intake delays the development of amyotrophic lateral sclerosis associated with reduced reticulum stress and autophagy in muscle of SOD1G93A mice.
J. Nutr. Biochem.
PUBLISHED: 03-27-2014
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Amyotrophic lateral sclerosis is a neurodegenerative disease associated with mutations in antioxidant enzyme Cu/Zn-superoxide dismutase 1. Albeit there is no treatment for this disease, new insights related to an exacerbated lipid metabolism have been reported. In connection with the hypermetabolic lipid status, the hypothesis whether nature of dietary fat might delay the progression of the disease was tested by using a transgenic mouse that overexpresses the human SOD1G93A variant. For this purpose, SOD1G93A mice were assigned randomly to one of the following three experimental groups: (1) a standard chow diet (control, n=21), (2) a chow diet enriched with 20% (w/w) extra virgin olive oil (EVOO, n=22) and (3) a chow diet containing 20% palm oil (palm, n=20). They received the diets for 8 weeks and the progression of the disease was assessed. On the standard chow diet, average plasma cholesterol levels were lower than those mice receiving the high-fat diets. Mice fed an EVOO diet showed a significant higher survival and better motor performance than control mice. EVOO group mice survived longer and showed better motor performance and larger muscle fiber area than animals receiving palm. Moreover, the EVOO-enriched diet improved the muscle status as shown by expression of myogenic factors (Myod1 and Myog) and autophagy markers (LC3 and Beclin1), as well as diminished endoplasmic reticulum (ER) stress through decreasing Atf6 and Grp78. Our results demonstrate that EVOO may be effective in increasing survival rate, improving motor coordination together with a potential amelioration of ER stress, autophagy and muscle damage.
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Phenotypic and genetic features of enteropathogenic Escherichia coli isolates from diarrheal children in the Ribeirão Preto metropolitan area, São Paulo State, Brazil.
APMIS
PUBLISHED: 02-20-2014
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This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors-encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype ? was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence-like (LAL) pattern to HEp-2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non-adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates.
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Potentially pathogenic Escherichia coli in healthy, pasture-raised sheep on farms and at the abattoir in Brazil.
Vet. Microbiol.
PUBLISHED: 01-21-2014
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Sheep harbor pathogenic Escherichia coli, which may cause severe disease in humans. In this study, the prevalence of Shiga toxin-producing E. coli (STEC) and enteropathogenic E. coli (EPEC) was examined in sheep feces and carcasses on three farms and at an abattoir in Brazil. The isolates were further characterized for the presence of markers recently associated with disease in humans, to investigate their possible origin and role as food-borne pathogens. At the abattoir, 99 carcass samples yielded two STEC and 10 EPEC isolates while 101 fecal samples yielded five EPEC and eight STEC isolates. On the other hand, on the farms, 202 samples yielded 44 STEC and eight EPEC isolates. The 77 isolates were typed by PFGE. Isolates with the same PFGE pattern and also those that were not restricted with XbaI were termed as "clones" (n=49). The isolates of any one clone mostly originated from the same sampling site. In addition, seven isolates encoded for novel Stx2 variants and five for Stx2e, the subtype related to porcine edema disease, which was for the first time isolated from sheep feces and carcasses. Also, three stx2-only isolates harbored genes of predicted Stx2 variants that were formed by A and B subunits of different types including Stx2a and Stx2d. The EPEC isolates were heterogeneous, 21 (91.3%) of them possessing efa1, ehxA, lpfAO113 or paa genes associated with diarrhea in humans. Thus, using markers recently associated with disease, we have demonstrated that E. coli similar to those pathogenic for humans are present in the sheep intestinal microflora, particularly at the abattoir, underlining the potential for food-borne transmission.
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Synthesis of Pt Nanoparticles in Water-in-Oil Microemulsion: Effect of HCl on Their Surface Structure.
J. Am. Chem. Soc.
PUBLISHED: 01-21-2014
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The synthesis of shape-controlled nanoparticles is currently a hot research topic. However, from an applied point of view, there is still a lack of easy, cheap, and scalable methodologies. In this communication we report, for the first time, the synthesis of cubic platinum nanoparticles with a very high yield using a water-in-oil microemulsion method, which unlike others, such as the colloidal method, fulfills the previous requirements. This shape/surface structure control is determined by the concentration of HCl in the water phase of the microemulsion. The results reported here show that the optimal HCl percentage in the water phase is about 25% to obtain the highest amount of cubic nanostructures. Ammonia electro-oxidation is used as a surface structure sensitive reaction to illustrate HCl surface structure effects. Moreover, in situ electrochemical characterization has been performed to study the nanoparticle surface structure.
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Synthesis and electrocatalytic properties of H2SO4 -induced (100) Pt nanoparticles prepared in water-in-oil microemulsion.
Chemphyschem
PUBLISHED: 01-20-2014
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The increasing number of applications for shape-controlled metal nanoparticles (NPs) has led to the need for easy, cheap, and scalable methodologies. We report the synthesis of (100) preferentially oriented Pt NPs, with a particle size of 9 nm, by using a water-in-oil microemulsion method. The specific surface structure of the NPs is induced by the presence of H(2)SO(4) in the water phase of the microemulsion. Interestingly, the results reported herein show how increasing amounts of H(2)SO(4) lead to the formation of Pt NPs containing a larger amount of (100) sites on their surface. This preferential surface orientation is confirmed electrochemically by using the so-called hydrogen adsorption/desorption process. In addition, transmission electron microscopy measurements confirm the presence of cubic-like Pt NPs. Finally, the electrocatalytic properties of the Pt NPs are evaluated towards ammonia and CO electro-oxidations, which are (100) structure-sensitive reactions.
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Primary cutaneous cryptococcosis in an immunocompetent patient due to Cryptococcus gattii molecular type VGI in Brazil: a case report and review of literature.
Mycoses
PUBLISHED: 01-16-2014
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Primary Cutaneous Cryptococcosis is an uncommon infection caused by the yeast Cryptococcus neoformans and C. gattii. Few case reports are available in the literature describing in detail primary cutaneous cryptococcosis due to C. gattii in immunocompetent patients. Herein, we present a case of a 68-year-old immunocompetent male patient with erythematous nodular lesions on the right forearm due to C. gattii mating-type ? and molecular type VGI. The virulence factors test was performed for capsule diameter, melanin production and phospholipase activity. In vitro fluconazole testing showed the sensitivity profile of this clinical isolate. In addition, a review of the literature on this subject was carried out and verified that this is the first reported case of VGI in the south-east region of Brazil.
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Synthesis and anti-tuberculosis activity of the marine natural product caulerpin and its analogues.
Mar Drugs
PUBLISHED: 01-07-2014
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Caulerpin (1a), a bis-indole alkaloid from the marine algal Caulerpa sp., was synthesized in three reaction steps with an overall yield of 11%. The caulerpin analogues (1b-1g) were prepared using the same synthetic pathway with overall yields between 3% and 8%. The key reaction involved a radical oxidative aromatic substitution involving xanthate (3) and 3-formylindole compounds (4a-4g). All bis-indole compounds synthesized were evaluated against the Mycobacterium tuberculosis strain H37Rv, and 1a was found to display excellent activity (IC?? 0.24 µM).
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De novo design of non-coordinating indolones as potential inhibitors for lanosterol 14-?-demethylase (CYP51).
Chem. Pharm. Bull.
PUBLISHED: 01-07-2014
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The development of antifungal drugs that inhibit lanosterol 14-?-demethylase (CYP51) via non-covalent ligand interactions is a strategy that is gaining importance. A series of novel tetraindol-4-one derivatives with 1- and 2-(2,4-substituted phenyl) side chains were designed and synthesized based on the structure of CYP51 and fluconazole. The antifungal activities of these derivatives against eight human pathogenic filamentous fungi and yeast strains were evaluated in vitro by measuring the minimal inhibitory concentrations. Nearly all tested compounds 8a-g displayed activity against Candida tropicalis, Candida guilliermondii and Candida parapsilosis with a minimum inhibitory concentration (MIC) value until 8?µg?mL(-1), on the other hand compounds 7a-g showed activity against Aspergillus fumigatus with a MIC value of 31.25?µg?mL(-1). A molecular modeling study of the binding interactions between compounds 6, 7d, 8g and the active site of MtCYP51 was conducted based on the computational docking results.
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Households pro-environmental habits and investments in water and energy consumption: Determinants and relationships.
J. Environ. Manage.
PUBLISHED: 11-25-2013
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Economic instruments have received a lot of attention in the literature dealing with water and energy demand management. However factors driving households behaviour/habits and investment in water-saving and energy-saving equipment have been seldom studied. The main purpose of this article is to contribute to this literature by analysing the main determinants of a set of households conservation habits and pro-environmental investment decisions. Using household-level data from Spain, we show that conservation habits and the purchase of resource-efficient appliances are not independent.
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Improving the lethal effect of cpl-7, a pneumococcal phage lysozyme with broad bactericidal activity, by inverting the net charge of its cell wall-binding module.
Antimicrob. Agents Chemother.
PUBLISHED: 08-19-2013
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Phage endolysins are murein hydrolases that break the bacterial cell wall to provoke lysis and release of phage progeny. Recently, these enzymes have also been recognized as powerful and specific antibacterial agents when added exogenously. In the pneumococcal system, most cell wall associated murein hydrolases reported so far depend on choline for activity, and Cpl-7 lysozyme constitutes a remarkable exception. Here, we report the improvement of the killing activity of the Cpl-7 endolysin by inversion of the sign of the charge of the cell wall-binding module (from -14.93 to +3.0 at neutral pH). The engineered variant, Cpl-7S, has 15 amino acid substitutions and an improved lytic activity against Streptococcus pneumoniae (including multiresistant strains), Streptococcus pyogenes, and other pathogens. Moreover, we have demonstrated that a single 25-?g dose of Cpl-7S significantly increased the survival rate of zebrafish embryos infected with S. pneumoniae or S. pyogenes, confirming the killing effect of Cpl-7S in vivo. Interestingly, Cpl-7S, in combination with 0.01% carvacrol (an essential oil), was also found to efficiently kill Gram-negative bacteria such as Escherichia coli and Pseudomonas putida, an effect not described previously. Our findings provide a strategy to improve the lytic activity of phage endolysins based on facilitating their pass through the negatively charged bacterial envelope, and thereby their interaction with the cell wall target, by modulating the net charge of the cell wall-binding modules.
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Histoplasmosis in immunocompetent individuals living in an endemic area in the Brazilian Southeast.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 06-12-2013
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The distribution of infection by Histoplasma capsulatum in Brazil is heterogeneous, and the number of cases affecting immunocompetent individuals is relatively small. This study reports the epidemiological and clinical data regarding histoplasmosis in non-immunosuppressed individuals.
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Estimating the toxicity of ambient fine aerosols using freshwater rotifer Brachionus calyciflorus (Rotifera: Monogononta).
Environ. Pollut.
PUBLISHED: 04-30-2013
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The toxicity of atmospheric fine particulate matter (PM2.5) in Atlanta is assessed using freshwater rotifers (Brachionus calyciflorus). The PM-laden quartz filters were extracted in both water and methanol. Aerosol extracts were passed through a C-18 column to separate the PM components into hydrophobic and hydrophilic fractions. Toxicity data reported in the units of LC50 (concentration that kills 50% of the test population in 24 h) shows that ambient particles are toxic to the rotifers with LC50 values ranging from 5 to 400 ?g of PM. The methanol extract of the aerosols was substantially more toxic (8 ± 6 times) to the rotifers compared to the water extracts. A sizeable fraction (>70%) of toxicity was found to be associated with the hydrophobic fraction of PM. However, none of the bulk aerosol species was strongly correlated with the LC50 values suggesting a complicated mechanism of toxicity probably involving synergistic interactions of various PM components.
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Efficacy of voriconazole in experimental rat paracoccidioidomycosis.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 04-09-2013
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Amphotericin B, azole or sulfamide drugs are used for treatment of patients with paracoccidioidomycosis. Among the azole drugs, voriconazole was active in vitro against Paracoccidioides brasiliensis and showed efficacy in the treatment of patients infected with this fungus.In the present study the antifungal activity of voriconazole and of other drugs was compared in a rat model of paracoccidioidomycosis.
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It is time to abandon "expected bladder capacity." systematic review and new models for childrens normal maximum voided volumes.
Neurourol. Urodyn.
PUBLISHED: 03-30-2013
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There is an agreement to use simple formulae (expected bladder capacity and other age based linear formulae) as bladder capacity benchmark. But real normal childs bladder capacity is unknown.
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Sphingomyelin in high-density lipoproteins: structural role and biological function.
Int J Mol Sci
PUBLISHED: 02-19-2013
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High-density lipoprotein (HDL) levels are an inverse risk factor for cardiovascular diseases, and sphingomyelin (SM) is the second most abundant phospholipid component and the major sphingolipid in HDL. Considering the marked presence of SM, the present review has focused on the current knowledge about this phospholipid by addressing its variable distribution among HDL lipoparticles, how they acquire this phospholipid, and the important role that SM plays in regulating their fluidity and cholesterol efflux from different cells. In addition, plasma enzymes involved in HDL metabolism such as lecithin-cholesterol acyltransferase or phospholipid transfer protein are inhibited by HDL SM content. Likewise, HDL SM levels are influenced by dietary maneuvers (source of protein or fat), drugs (statins or diuretics) and modified in diseases such as diabetes, renal failure or Niemann-Pick disease. Furthermore, increased levels of HDL SM have been shown to be an inverse risk factor for coronary heart disease. The complexity of SM species, described using new lipidomic methodologies, and their distribution in different HDL particles under many experimental conditions are promising avenues for further research in the future.
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Diastereoselective synthesis of C60/steroid conjugates.
J. Org. Chem.
PUBLISHED: 01-31-2013
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The design and synthesis of fullerene-steroid hybrids by using Pratos protocol has afforded new fullerene derivatives endowed with epiandrosterone, an important naturally occurring steroid hormone. Since the formation of the pyrrolidine ring resulting from the 1,3-dipolar cyloaddition reaction takes place with generation of a new stereogenic center on the C2 of the five-membered ring, the reaction proceeds with formation of a diastereomeric mixture [compounds 6 and 7 in 70:30 ratio, 8 and 9 in 26:74 ratio (HPLC)] in which the formation of the major diasteroisomers 6 and 9 is consistent with an electrophilic attack of [60]fullerene on the Re face of the azomethine ylide directed by the steroidic unit. The chiroptical properties of these conjugates reveal typical Cotton effects in CD spectra that have been used to assign the absolute configuration of the new fulleropyrrolidines. The electrochemical study of the new compounds reveals the presence of four quasi-reversible reduction waves which are cathodically shifted in comparison with the parent C60, thus ascertaining the proposed structures.
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Postprandial changes in high density lipoproteins in rats subjected to gavage administration of virgin olive oil.
PLoS ONE
PUBLISHED: 01-29-2013
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The present study was designed to verify the influence of acute fat loading on high density lipoprotein (HDL) composition, and the involvement of liver and different segments of small intestine in the changes observed.
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In vitro activity of antimicrobial combinations against multidrug-resistant Pseudomonas aeruginosa.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 01-23-2013
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Pseudomonas aeruginosa isolates related to nosocomial infections are often resistant to multiple antibacterial agents. In this study, antimicrobial combinations were evaluated to detect in vitro synergy against clinical isolates of P. aeruginosa.
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Dietary oleanolic acid mediates circadian clock gene expression in liver independently of diet and animal model but requires apolipoprotein A1.
J. Nutr. Biochem.
PUBLISHED: 01-22-2013
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Oleanolic acid is a triterpene widely distributed throughout the plant kingdom and present in virgin olive oil at a concentration of 57 mg/kg. To test the hypotheses that its long-term administration could modify hepatic gene expression in several animal models and that this could be influenced by the presence of APOA1-containing high-density lipoproteins (HDLs), diets including 0.01% oleanolic acid were provided to Apoe- and Apoa1-deficient mice and F344 rats. Hepatic transcriptome was analyzed in Apoe-deficient mice fed long-term semipurified Western diets differing in the oleanolic acid content. Gene expression changes, confirmed by reverse transcriptase quantitative polymerase chain reaction, were sought for their implication in hepatic steatosis. To establish the effect of oleanolic acid independently of diet and animal model, male rats were fed chow diet with or without oleanolic acid, and to test the influence of HDL, Apoa1-deficient mice consuming the latter diet were used. In Apoe-deficient mice, oleanolic acid intake increased hepatic area occupied by lipid droplets with no change in oxidative stress. Bmal1 and the other core component of the circadian clock, Clock, together with Elovl3, Tubb2a and Cldn1 expressions, were significantly increased, while Amy2a5, Usp2, Per3 and Thrsp were significantly decreased in mice receiving the compound. Bmal1 and Cldn1 expressions were positively associated with lipid droplets. Increased Clock and Bmal1 expressions were also observed in rats, but not in Apoa1-deficient mice. The core liver clock components Clock-Bmal1 are a target of oleanolic acid in two animal models independently of the diets provided, and this compound requires APOA1-HDL for its hepatic action.
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Differences in the contractile properties of the knee extensor and flexor muscles in professional road cyclists during the season.
J Strength Cond Res
PUBLISHED: 01-11-2013
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The purpose of this study was to establish reference values of tensiomyography (TMG) in professional road cyclists and to examine how the planned periods of the Season produce differences in the muscles: vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), and biceps femoris (BF), and to determine how these differences may depend on each cyclist, the assessed muscle, and the side of the body. Ten professional road cyclists (27.5 ± 5.5 years; 178.2 ± 7.8 cm; 65.6 ± 5.46 kg; 72.1 ± 3.7 ml·kg·min V[Combining Dot Above]O2; 6 ± 0.4 W·kg) were assessed by TMG, in microcycle recovery, at 2 moments of periods during the season: preparation period (PP) and competition period (CP). Students t contrast for paired groups, Cohens d effect sizes, and a repeated measures analysis of variance (ANOVA) was applied. We did not find significant differences (p < 0.01) between the lower limbs. The results showed a significantly large increment between the time contraction (TC) values of the PP and CP in the muscles VM (28.7 ± 5.5 vs. 40.6 ± 14.4 milliseconds; 41.4%, p < 0.05, d = 1.1), VL (28.3 ± 4.9 vs. 40.6 ± 10.2 milliseconds; 43.4%, p < 0.05, d = 1.53), and RF (35.9 ± 6.9 vs. 45.9 ± 16.2 milliseconds; 27.8%, p < 0.05, d = 0.8). Nevertheless, TC of the BF presents a significantly large decrease in the CP (35.9 ± 9.9 vs. 28.2 ± 5.2 milliseconds; -21.4%, p < 0.05, d = 0.97). Radial muscle displacement (DM) values are slightly lower during the CP, but the difference is not significant. ANOVA confirmed that these differences depend on the evaluated muscles (TC p = 0.02; DM p = 0.001) and on the cyclists (TC p = 0.001; DM p = 0.001) and does not depend on the side of the body. In conclusion, the TC values during the Season show marked differences between the knee extensors (large increased) and the knee flexor (large decreased). The DM has not changed significantly, keeping the muscular and tendon stiffness.
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Dibenzo[1,2,5]thiadiazepines are non-competitive GABAA receptor antagonists.
Molecules
PUBLISHED: 01-05-2013
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A new process for obtaining dibenzo[c,f][1,2,5]thiadiazepines (DBTDs) and their effects on GABA(A) receptors of guinea pig myenteric neurons are described. Synthesis of DBTD derivatives began with two commercial aromatic compounds. An azide group was obtained after two sequential reactions, and the central ring was closed via a nitrene to obtain the tricyclic sulfonamides (DBTDs). Whole-cell recordings showed that DBTDs application did not affect the holding current but inhibited the currents induced by GABA (I(GABA)), which are mediated by GABA(A) receptors. These DBTDs effects reached their maximum 3 min after application and were: (i) reversible, (ii) concentration-dependent (with a rank order of potency of 2c = 2d > 2b), (iii) mediated by a non-competitive antagonism, and (iv) only observed when applied extracellularly. Picrotoxin (which binds in the channel mouth) and DBTDs effects were not modified when both substances were simultaneous applied. Our results indicate that DBTD acted on the extracellular domain of GABA(A) channels but independent of the picrotoxin, benzodiazepine, and GABA binding sites. DBTDs used here could be the initial model for synthesizing new GABA(A) receptor inhibitors with a potential to be used as antidotes for positive modulators of these receptors or to induce experimental epilepsy.
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Cost-benefit analysis of riparian protection in an eastern Canadian watershed.
J. Environ. Manage.
PUBLISHED: 01-04-2013
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Forested riparian buffers have proved to be an effective management practice that helps maintain ecological goods and services in watersheds. In this study, we assessed the non-market benefits and opportunity costs associated with implementing these buffers in an eastern Canadian watershed using contingent valuation and wood supply modeling methods, respectively. A number of buffer scenarios were considered, including 30 and 60 m buffers on woodlots and on all land (including woodlots, agricultural, and residential lands) in the watershed. Household annual WTP estimates ranged from -$6.80 to $42.85, and total present value benefits ranged from -$11.7 to $121.7 million (CDN 2007), depending on the buffer scenario, affected population, time horizon, and econometric modeling assumptions considered. Opportunity cost estimates range from $1.3 to $10.4 million in present value terms, depending on silvicultural and agriculture land rental rate assumptions. Overall, we found that the net present value of riparian buffers was positive for the majority of scenarios and assumptions. Some exceptions were found under more conservative benefit, and higher unit cost, assumptions. These results provide decision makers with data on stated benefits and opportunity costs of riparian buffers, as well as insight into the importance of modeling assumptions when using this framework of analysis.
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Effect of substituents and protonation on the mechanism of 1,3-dipolar retro-cycloaddition reaction of pyrrolidino[60]- and [70]fullerenes.
J Mass Spectrom
PUBLISHED: 10-21-2011
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The mass spectra of new substituted pyrrolidino[60]- and [70]fullerenes have been obtained using electrospray ionization conditions in the positive and negative mode of detection with two different mass spectrometers, a quadrupole ion trap and a Fourier transform ion cyclotron resonance. Radical anions M(?-) and deprotonated molecules [M-H](-) are formed under negative electrospray ionization mass spectrometry conditions, and the collision-induced dissociations of both ionic species have been studied. Either negative odd-electron ions or negative even-electron ions undergo a retro-cycloaddition process forming the corresponding fullerene product ions C(60)(?-) and C(70)(?-). The generation of fullerene radical anions from deprotonated molecules is a new exception of the "even-electron rule." In contrast, the protonated molecules [M + H](+) obtained from the positive mode of detection do not undergo this cycloreversion reaction, and the MS(n) experiment reveals a variety of eliminations of neutral molecules involving different hydrogen shifts and multiple bond cleavages that lead eventually to substituted methanofullerene fragment ions. The observed fragmentations can be correlated with the electronic character of the substituents attached to the heterocyclic moiety. The results obtained from the thermal reactions of these compounds, carried out under different pH conditions, correlate well with those obtained in gas phase. The different behaviors between protonated and unprotonated molecules and ions can be explained assuming that the retro-cycloaddition reaction takes place only when the nitrogen atom of the pyrrolidine ring (the basic center of the molecule) is unprotonated both in gas and condensed phase. The protonation of the NH group inhibits the cycloreversion process, and therefore different fragmentations take place. The detailed mechanisms of the formation and evolution of the intermediate fragments are described.
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HIV Risk Behavior among Youth in the Dominican Republic: The Role of Alcohol and Other Drugs.
J Int Assoc Physicians AIDS Care (Chic)
PUBLISHED: 09-12-2011
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Existing literature related to HIV in the Dominican Republic has tended to neglect the unique role of tourism areas as distinct ecologies facilitative of sexual risk behavior, particularly HIV vulnerability and transmission. Furthermore, limited attention has focused on Dominican adolescents living in close proximity to tourism areas who have become increasingly exposed to alcohol due to the expanding tourism industry in the Dominican Republic. While most previous analyses of the effects of alcohol on adolescent sexual risk behavior have focused on the transient effects of alcohol on judgment and decision making, the effects of chronic alcohol use on sexual behavior has been a neglected area of research. Our study explores the relationship between chronic alcohol use, the parent-adolescent relationship, affective factors such as self-esteem, and intentions to engage in sex. We examine the above factors within the context of tourism areas which represent a unique ecology of alcohol availability and consumption and HIV risk. We discuss implications for developing applied family-based programs to target Dominican adolescent alcohol use and sexual risk behavior in tourism areas of high alcohol exposure.
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Paracoccidioidomycosis epidemiological features of a 1,000-cases series from a hyperendemic area on the southeast of Brazil.
Am. J. Trop. Med. Hyg.
PUBLISHED: 09-08-2011
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Paracoccidioidomycosis has been known for over 100 years, and until now, there were only few estimates of the diseases incidence. We aim to analyze 1,000 cases treated between 1960 and 1999 at Ribeirão Preto city, São Paulo, Brazil, where the diseases incidence range detected was 1.6 to 3.7 cases per 100,000 habitants per year (mean = 2.7 cases/year). We observed a male to female ratio of 6:1 and an age distribution from 3 to 85 years. The acute/subacute form of the disease accounted for 25.4% of cases. Most of the patients (93.5%) had lived or worked in rural areas before the disease development. Smoking and alcoholism were reported by 64.7% and 37.2% of patients, respectively. Comorbidities identified included tuberculosis (8.3%), Chagas disease (8.6%), and human immunodeficiency virus/acquired immunodeficiency syndrome (4.2%). The present study revealed an area in Brazil where paracoccidioidomycosis is hyperendemic (has the highest reported incidence of this disease); this endemic area is probably caused by geological and climatic conditions as well as intensive agriculture.
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Ultrafast dynamics of aniline in the 294-234 nm excitation range: the role of the ??? state.
J Chem Phys
PUBLISHED: 08-10-2011
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The ultrafast relaxation of jet-cooled aniline was followed by time-resolved ionization, after excitation in the 294-234 interval. The studied range of energy covers the absorption of the two bright ??? excitations, S(1) and S(3), and the almost dark S(2) (???) state. The employed probe wavelengths permit to identify different ultrafast time constants related with the coupling of the involved electronic surfaces. A ?(1) = 165 ± 30 fs lifetime is attributed to dynamics along the S(2) (???) repulsive surface. Other relaxation channels as the S(1)?S(0) and S(3)?S(1) internal conversion are also identified and characterized. The work provides a general view of the photophysics of aniline, particularly regarding the role of the ??? state. This state appears as minor dissipation process due to the ineffective coupling with the bright S(1) and S(3) states, being the S(1)?S(0) internal conversion the main non-radiative process in the full studied energy range. Additionally, the influence of the off-resonance adiabatic excitation of higher energy electronic states, particularly S(3), is also observed and discussed.
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Quantification of HIV-1 viral RNA in the blood in needles used for venous puncture in HIV-infected individuals.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 08-08-2011
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Occupational HIV infection among healthcare workers is an important issue in exposures involving blood and body fluids. There are few data in the literature regarding the potential and the duration of infectivity of HIV type 1 (HIV-1) in contaminated material under adverse conditions.
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Bioconcentration and localization of lead in the freshwater rotifer Brachionus calyciflorus Pallas 1677 (Rotifera: Monogononta).
Aquat. Toxicol.
PUBLISHED: 08-05-2011
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We studied how lead is bioconcentrated and distributed in the rotifer Brachionus calyciflorus using metal histochemistry to locate lead granules, Leadmium Green® analysis to establish the route of uptake, atomic absorption to determined the bioconcentration factor (BCF), and detected the presence of microelements in the cuticle by X-ray microanalysis with scanning electron microscopy. Our results indicate: (a) the digestive system is the main route of lead uptake in the rotifer B. calyciflorus, (b) after 24-h lead is deposited in granules in the mastax and vitellarium, (c) our energy-dispersive X-ray microanalysis indicates decalcification taking place in the cuticle of the rotifer after a 24-h lead exposure, and (d) we determined a BCF = 115 for lead after a 24 h exposure. However, the route of mobilization and storage of intracellular lead are still not fully understood in B. calyciflorus.
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Alternative approaches to dealing with respondent uncertainty in contingent valuation: a comparative analysis.
J. Environ. Manage.
PUBLISHED: 08-02-2011
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Several strategies have been proposed to deal with response uncertainty in contingent valuation. One approach, often applied to address issues of hypothetical bias, recodes and/or reweights responses according to stated levels of certainty but so far few analyses compare alternative recoding and reweighting strategies. We explore the choice among alternative strategies that exploit a numerical certainty scale obtained from a follow-up to the payment question in a valuation survey about a whale conservation program. Two novel variations of previously followed approaches perform best on our dataset in terms of the efficiency of estimates. The first one uses an exponential transformation of the numerical certainty scale as a weight in the willingness to pay regression. The other one is based on constructing a continuous willingness to pay variable with the highly certain "yes" and "no" original responses to the payment question as extreme values and with mid-point values that correspond to the original "dont know" responses. We find, though, that the effect of using different treatment strategies on mean willingness to pay is rarely statistically significant and we fail to detect a consistent effect on the efficiency of the estimation regardless of the strategy applied.
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[Impact of anxiety and depression on the physical status and daily routines of cancer patients during chemotherapy].
Psicothema
PUBLISHED: 07-22-2011
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The evolution of symptoms, emotional state and daily routines in patients with breast cancer and lung cancer during treatment with intravenous chemotherapy (CT) is described and the influence of anxiety and depression on these variables is analyzed. 66 patients, 29 with breast cancer and 37 with lung cancer, were evaluated before starting treatment, and after completing the first, second and last cycle of CT using the Hospital Anxiety and Depression Scale (HADS), rating scales and interview. Less than 30% of the patients showed clinical anxiety or depression according to the HADS. Throughout the treatment, tiredness, fatigue and nausea increased significantly and work and leisure activity decreased. Concern about the future of relatives and insomnia increased significantly over time in patients with breast cancer whereas they decreased in patients with lung cancer. By introducing the HADS scores as covariates, it was found that most differences are due to the time factor and the type of cancer. During treatment with CT, emotional disturbances do not seem to have significant impact on the symptoms and changes in daily life reported by cancer patients.
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Dissemination of blaKPC-2 by the spread of Klebsiella pneumoniae clonal complex 258 clones (ST258, ST11, ST437) and plasmids (IncFII, IncN, IncL/M) among Enterobacteriaceae species in Brazil.
Antimicrob. Agents Chemother.
PUBLISHED: 05-16-2011
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This article reports the spread of bla(KPC-2) in the Sao Paulo and Rio de Janeiro states, facilitated by globally spread K. pneumoniae clonal complex 258 (CC258) clones (ST258, ST11, and ST437) and a diversity of plasmids (IncFII, IncN, and IncL/M, two untypeable plasmids carrying Tn4401a or Tn4401b) successfully disseminated among species of the Enterobacteriaceae (Enterobacter cloacae, Serratia marcescens, and Citrobacter freundii). It also constitutes the first description of sequence type 258 (ST258) in Brazil, which was associated with a nosocomial hospital outbreak in Ribeirao Preto city.
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Toxicity of cadmium, lead, mercury and methyl parathion on Euchlanis dilatata Ehrenberg 1832 (Rotifera: Monogononta).
Bull Environ Contam Toxicol
PUBLISHED: 05-13-2011
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Acute toxicity tests with Cd, Pb, Hg, and methyl parathion were developed to compare the sensitivity of the rotifer Euchlanis dilatata with other model organisms used in aquatic ecotoxicology. Cd was the most toxic chemical (LC50 = 14.8 ?g L(-1)), while methyl parathion was the least toxic (LC50 = 864.2 ?g L(-1)). E. dilatata was more sensitive that other rotifer species, particularly of the genera Brachionus and Lecane. However, E. dilatata was less sensitive to mercury and methyl parathion than the crustacean, Daphnia magna. The high sensitivity of E. dilatata suggests that it may be an adequate benthic model to use in toxicity assessments of metal-contaminated sediments.
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Efficient sonochemical synthesis of alkyl 4-aryl-6-chloro-5-formyl-2-methyl-1,4-dihydropyridine-3-carboxylate derivatives.
Ultrason Sonochem
PUBLISHED: 04-21-2011
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A facile, efficient and environment-friendly protocol for the synthesis of 6-chloro-5-formyl-1,4-dihydropyridine derivatives has been developed by the convenient ultrasound-mediated reaction of 2(1H)pyridone derivatives with the Vilsmeier-Haack reagent. This method provides several advantages over current reaction methodologies including a simpler work-up procedure, shorter reaction times and higher yields.
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Radiologic findings of osteoarticular infection in paracoccidioidomycosis.
Skeletal Radiol.
PUBLISHED: 04-15-2011
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To report the radiological abnormalities of osteoarticular involvement in paracoccidioidomycosis (PCM).
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Evidence of lead biomagnification in invertebrate predators from laboratory and field experiments.
Environ. Pollut.
PUBLISHED: 03-04-2011
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This report includes atomic absorption data from water column, elutriates and zooplankton that demonstrate that lead biomagnifies at El Niágara reservoir, Mexico. Results include field data (bioaccumulation factors) (BAFs) and laboratory data (bioconcentration factors) (BCFs). Two findings: high BAFs for invertebrate predator like Acanthocyclops robustus, Asplanchna brightwellii, Culex sp. larvae, and Hyalella azteca, compared to grazer species Moina micrura and Simocephalus vetulus; low BCFs found for some predators, suggested that lead biomagnifications were taking place. The presence of Moina micrura in the gut of Asplanchna allowed us to design experiments where A. brightwellii was fed lead-exposed M. micrura neonates. The BAF of Asplanchna was 123,684, BCF was 490. Asplanchna individuals fed exposed Moina had 13.31 times more lead than Asplanchna individuals just exposed 48-h to lead, confirming that lead biomagnification occurs. Results of two fish species showed no lead biomagnification, suggesting that lead biomagnification might be restricted to invertebrate predators.
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Frame stability and anatomical QA in radiosurgery.
Acta Neurochir (Wien)
PUBLISHED: 03-03-2011
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The aim of the study was to analyze whether the fixation of the stereotactic frame is stable and whether the location of the treated target coincides with its anatomical location during Gamma Knife(®) surgery (GKS).
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Exploiting the passive dynamics of a compliant leg to develop gait transitions.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 03-02-2011
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In the area of bipedal locomotion, the spring-loaded inverted pendulum model has been proposed as a unified framework to explain the dynamics of a wide variety of gaits. In this paper, we present an analysis of the mathematical model and its dynamical properties. We use the perspective of hybrid dynamical systems to study the dynamics and define concepts such as partial stability and viability. With this approach, on the one hand, we identify stable and unstable regions of locomotion. On the other hand, we find ways to exploit the unstable regions of locomotion to induce gait transitions at a constant energy regime. Additionally, we show that simple nonconstant angle of attack control policies can render the system almost always stable.
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Cell-free antigens from Paracoccidioides brasiliensis drive IL-4 production and increase the severity of paracoccidioidomycosis.
PLoS ONE
PUBLISHED: 02-02-2011
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The thermally dimorphic fungus Paracoccidioides brasiliensis (Pb) is the causative agent of paracoccidioidomycosis (PCM), one of the most frequent systemic mycosis that affects the rural population in Latin America. PCM is characterized by a chronic inflammatory granulomatous reaction, which is consequence of a Th1-mediated adaptive immune response. In the present study we investigated the mechanisms involved in the immunoregulation triggered after a prior contact with cell-free antigens (CFA) during a murine model of PCM. The results showed that the inoculation of CFA prior to the infection resulted in disorganized granulomatous lesions and increased fungal replication in the lungs, liver and spleen, that paralleled with the higher levels of IL-4 when compared with the control group. The role of IL-4 in facilitating the fungal growth was demonstrated in IL-4-deficient- and neutralizing anti-IL-4 mAb-treated mice. The injection of CFA did not affect the fungal growth in these mice, which, in fact, exhibited a significant diminished amount of fungus in the tissues and smaller granulomas. Considering that in vivo anti-IL-4-application started one week after the CFA-inoculum, it implicates that IL-4-CFA-induced is responsible by the mediation of the observed unresponsiveness. Further, the characterization of CFA indicated that a proteic fraction is required for triggering the immunosuppressive mechanisms, while glycosylation or glycosphingolipids moieties are not. Taken together, our data suggest that the prior contact with soluble Pb antigens leads to severe PCM in an IL-4 dependent manner.
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Mass spectrometry studies of the retro-cycloaddition reaction of pyrrolidino and 2-pyrazolinofullerene derivatives under negative ESI conditions.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 01-29-2011
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Substituted pyrrolidino- and 3-alkyl-2-pyrazolinofullerenes ionize under ESI and MALDI mass spectrometry conditions and negative mode of detection undergoing mass spectral fragmentations, which can be easily correlated with the reported results for the thermal and electrochemical retro-cycloaddition reactions of these compounds. 2-Pyrazolinofullerenes lead directly to a [60]fullerene product ion formed through a retro-cycloaddition process regardless of the substituents attached at the carbon and nitrogen atoms of the heterocyclic ring. These results are different from whose reported for the thermal and electrochemical processes. In contrast, pyrrolidinofullerenes undergo different fragmentative reactions depending upon the substituents (hydrogen, alkyl, or acyl) attached at the nitrogen atom of the heterocyclic ring leading eventually to the pristine C(60) in the last step of the fragmentation pathway.
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Selection of reference genes for gene expression studies in rats.
J. Biotechnol.
PUBLISHED: 01-08-2011
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Selection of the most stable reference gene is critical for a reliable interpretation of gene expression data using RT-PCR. In order so, 17 commonly used genes were analyzed in Wistar rat duodenum, jejunum, ileum and liver following a fat gavage and at two time periods. These reference genes were also tested in liver from Zucker (fa/fa) on a long-term dietary trial. Four strategies were used to select the most suitable reference gene for each tissue: ranking according to biological coefficient of variation and further validation by statistical comparison among groups, geNorm, NormFinder and BestKeeper programs. No agreement was observed among these approaches for a particular gene, nor a common gene for all tissues. Furthermore we demonstrated that normalising using an inadequate reference conveyed into false negative and positive results. The selection of genes provided by BestKeeper resulted in more reliable results than the other statistical packages. According to this program, Tbp, Ubc, Hprt and Rn18s were the best reference genes for duodenum, jejunum, ileum and liver, respectively following a fat gavage in Wistar rats and Rn18s for liver in another rat strain on a long-term dietary intervention. Therefore, BestKeeper is highly recommendable to select the most stable gene to be used as internal standard and the selection of a specific reference expression gene requires a validation for each tissue and experimental design.
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Postprandial transcriptome associated with virgin olive oil intake in rat liver.
Front Biosci (Elite Ed)
PUBLISHED: 01-04-2011
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Liver has been proposed as a gatekeeper that regulates postprandial lipemia and a potential target for regulation by acute intake of virgin olive oil. To characterize the hepatic gene expression response to a fat gavage, male rats were fed a bolus of 5 ml of extra-virgin olive oil and the hepatic mRNA expression analyzed 4 hours later using DNA microarrays. To provide an initial screening of candidate genes, only twenty one with remarkably modified expression between both conditions (signal log2 ratio > 2.5 or < -2.5) were considered and confirmed by quantitative real time PCR. Those that presented biological significance were also analyzed 8 hours after the experimental approach. Hepatic A2m Slc13a5 and Nrep mRNA expressions were found significantly changed in both studied conditions and showed the highest significant associations with postprandial plasma triglycerides and lack of association with basal triglyceridemia. These results highlight new gene regulation in liver by postprandial triglyceridemia and will help to understand the complex human pathology providing the involvement of hepatic proteins and new strategies to cope with postprandial metabolism.
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Design and synthesis of anti-MRSA benzimidazolylbenzene-sulfonamides. QSAR studies for prediction of antibacterial activity.
Molecules
PUBLISHED: 11-22-2010
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A series of benzimidazolylbenzenesulfonamide compounds containing electron-releasing and electron-withdrawing substituents were synthesized and tested for their in vitro antibacterial activity. Two BZS compounds showed strong antibacterial activity against methicillin-resistant Staphylococcus aureus and Bacillus subtilis. Quantitative studies of their structure-activity relationship using a simple linear regression analysis were applied to explore the correlation between the biological activity and the charges on acidic hydrogen atoms in the synthesized compounds.
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Inhibition of two enzyme systems in Euchlanis dilatata (Rotifera: Monogononta) as biomarker of effect of metals and pesticides.
Biomarkers
PUBLISHED: 10-27-2010
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The inhibitory effects on esterases and phospholipase A2 (PLA2) in the freshwater rotifer Euchlanis dilatata, native to Mexico, were assessed by fluorimetry after in vivo exposure (30?min) in laboratory conditions to sublethal concentrations of metals and pesticides. EC(50) values for esterases ranged from 7.9?×?10(-7) for DDT to 61.9 ?g l(-1) for methyl parathion, while corresponding values for PLA2 ranged from 0.96?×?10(-6) for mercury to 69.2 ?g l(-1) for lead. These enzyme systems in E. dilatata are very sensitive to the tested agents and suggest they would be suitable biomarkers. However, sensitivity to other environmental contaminants should be investigated in laboratory conditions and field studies to assess their potential as environmental biomarkers.
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Synthesis of 5,6-dihydropyrrolo[2,1-a]isoquinolines featuring an intramolecular radical-oxidative cyclization of polysubstituted pyrroles, and evaluation of their cytotoxic activity.
Org. Biomol. Chem.
PUBLISHED: 07-29-2010
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A three-step protocol for the synthesis of 1,2,3,8,9-pentasubstituted-5,6-dihydropyrrolo[2,1-a]isoquinolines is described, using van Leusens polysubstituted pyrrole construction followed by intramolecular radical-oxidative cyclization of the isoquinoline system. The cytotoxic activities of the dihydropyrroloisoquinolines were tested on six tumor cell lines. Preliminary structure-activity studies revealed the importance of the identity of the aromatic substituent at the C-2 position, particularly a phenyl, m-(amino) phenyl or m-(cyclohexylmethylpiperazinamide) phenyl substituent, for cytotoxic activity.
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Comparing different methods used to collect material for a microbiological evaluation of patients with chronic rhinosinusitis.
Braz J Otorhinolaryngol
PUBLISHED: 07-27-2010
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There is still controversy on which is the best method to collect the secretion directly from the middle meatus or maxillary sinus in patients with chronic rhinosinusitis.
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Affordability of residential water tariffs: alternative measurement and explanatory factors in southern Spain.
J. Environ. Manage.
PUBLISHED: 07-01-2010
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Using information on a basic or "lifeline" level of domestic water use obtained from a water demand function based on a Stone-Geary utility function, a minimum water threshold of 128 m(3) per household per year was estimated in a sample of municipalities in Southern Spain. As a second objective, water affordability indexes were then calculated that relate the cost of such lifeline to average municipal income levels. The analysis of the factors behind the differences in that ratio across Andalusian municipalities shows that the relative cost of purchasing the lifeline appears inversely related to average income levels, revealing an element of regressivity in the component of water tariffs affecting the least superfluous part of the households consumption. The main policy recommendation would involve redesigning water tariffs in order to improve access for lower income households to an amount of water sufficient to cover their basic needs. The proposed methodology could be applied to other geographical areas, both from developed and from developing countries, in order to analyze the degree of progressivity of the water tariffs currently in effect and in order to guide the design of more equitable regulatory policies.
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[Abdominal girth utility as a method of metabolic syndrome screening in people with hypertension].
Rev. Esp. Salud Publica
PUBLISHED: 06-24-2010
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The most useful criteria for diagnosis of the Metabolic Syndrome (MS) are those proposed by the ATP-III from NCEP 2001, reviewed in 2005. Waist circumference is one of the criteria included in the ATP-III estimate. Given the high incidence of coronary disease attributable to this risk factor, it seems interesting to evaluate its performance as an isolated parameter for the screening of MS among people with a variety of other prevalent cardiovascular risk factors, such as high blood pressure.
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Maxillary sinuses microbiology from patients with chronic rhinosinusitis.
Braz J Otorhinolaryngol
PUBLISHED: 05-19-2010
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There isnt definitive and consistent data concerning the distribution of bacterial species in patients with Chronic Sinusitis (CS). The variability of the results from studies in CS may be due to the different techniques used as collection method, variations in culture methods, previous antibiotic use, and difficulty in distinguishing bacterial flora from pathogenic agents.
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Serological diagnosis of paracoccidioidomycosis in HIV-coinfected patients.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 04-30-2010
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Paracoccidioidomycosis should be differentiated from other opportunistic diseases in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients who live in Latin America. Laboratory investigation can begin with serological tests, which are rapid and efficient. In the present study, double immunodiffusion (DID), counterimmunoelectrophoresis (CIEP) and an enzyme linked immunosorbent assay (ELISA) tests were assessed for the detection of anti-Paracoccidioides brasiliensis antibodies in 40 patients coinfected with HIV. The results were compared to those obtained for 75 non-HIV-infected patients with endemic paracoccidioidomycosis. Anti-P. brasiliensis antibodies were detected in 65% (DID), 79% (CIEP) and 95% (ELISA) of the patients with HIV/AIDS, significantly lower rates than those detected in cases of endemic paracoccidioidomycosis, which were 89%, 99% and 100%, respectively. The reactive sera of HIV-infected patients also showed lower anti-P. brasiliensis antibody titres than those of non-HIV-infected patients. Despite the lower intensity of the specific humoral response, serological tests are useful for the diagnosis of opportunistic paracoccidioidomycosis in the HIV/AIDS population. We suggest optimization of the laboratory diagnosis by combining the ELISA test with CIEP or DID.
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Comparing toxicity endpoints on Lecane quadridentata (Rotifera: Monogononta) exposed to two anticholinesterases pesticides.
Environ. Toxicol.
PUBLISHED: 04-15-2010
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Toxicity tests were performed on the freshwater rotifer Lecane quadridentata exposed to the pesticides carbaryl and methyl parathion (lethal, sublethal, and chronic) to compare the sensitivity between different endpoints: (a) 48-h mortality; (b) 30-min in vivo inhibition of esterase activity; (c) 5-day inhibition of the instantaneous growth rate. The emphasis of this work was to find the most appropriate endpoint to evaluate the toxicity of these pesticides in view of their sensitivity, duration, and ecological relevance. The comparison between the three toxicity tests show that the 5-day chronic tests have the lowest EC50 (2.22 and 6.6 mg/L), lowest-observed-effect concentration (2.5 and 2.5 mg/L), and no-observed-effect concentration (1.0 and 1.2 mg/L) values for carbaryl and methyl parathion, respectively. This indicates that the estimate of the instantaneous rate of natural increase r is the most sensitive endpoint regarding the toxicity of these pesticides. This sensitivity might be due to the effect on reducing the growth potential form the first generation on. Lethal and sublethal tests are closely related, suggesting that the immediate effect after inhibition of esterases is death. In general, the sensitivity of L. quadridentata is similar to other species of rotifers exposed to methyl parathion. Therefore, the 5-day chronic toxicity test with the freshwater rotifer L. quadridentata should be considered a good candidate to evaluate the effect of anticholinesterase pesticides, due to its high sensitivity and ecological relevance.
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An assessment of chemical and physical parameters, several contaminants including metals, and toxicity in the seven major wastewater treatment plants in the state of Aguascalientes, Mexico.
J Environ Sci Health A Tox Hazard Subst Environ Eng
PUBLISHED: 04-15-2010
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Forty-eight hours acute toxicity tests were employed with Daphnia magna and Lecane quadridentata to assess the influents and effluents of the seven most important wastewater treatment plants (WTP) in the state of Aguascalientes, Mexico, during the 2006 dry and rainy seasons. The WTP of the City of Aguascalientes treated 1948 Ls(-1). The remaining six plants treated wastewater in the range from 28 to 93 Ls(-1). Plants efficiently removed toxicity when Daphnia magna was used as a model organism, but performed poorly when the freshwater rotifer Lecane quadridentata was employed. It was observed that biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), conductivity, dissolved oxygen (DO), pH, phenol, methylene blue active substances (MBAS), temperature, and total suspended solids (TSS) were within the maximum allowed levels (MAL) in the effluents during the rainy season. Whereas the BOD(5), total nitrogen, total dissolved solids (TDS) and TSS showed levels greater than the MAL in effluents during the dry season. The levels of BOD, MBAS, and total nitrogen were greater than the MAL in influents. In contrast, the values of TDS and TSS in influents were above the MAL during the rainy season. In the dry season the levels of aluminum (Al), iron (Fe), zinc (Zn), manganese (Mn), chromium (Cr), mercury (Hg) and lead (Pb) in influents and Fe, Mn and Pb in effluents were above the MAL. During the rainy season the levels of Mn, Cr and Hg in influents and those of Mn in effluents were above the MAL. When D. magna was used as model organism, acute toxicity units (aTU) for influents ranged from 0.2 to 4.4 and from 0.1 to 0.2 for effluents. These values for effluents are acceptable according to international guidelines. However, when L. quadridentata was the model organism, ranges were from 2.0 to 8.3 aTU in influents and from 1.6 to 2.6 aTU in effluents. The treated water that discharges into the San Pedro River would be considered toxic. The results of the toxicity tests demonstrated that the freshwater rotifer Lecane quadridentata was more sensitive (in 89.3% of the samples) than the cladoceran Daphnia magna when both organisms were exposed to the influents and effluents of the wastewater treatment plants.
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Ultrasound-assisted one-pot, four component synthesis of 4-aryl 3,4-dihydropyridone derivatives.
Ultrason Sonochem
PUBLISHED: 03-25-2010
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The condensation of Meldrums acid, aromatic aldehydes, alkyl acetoacetates and ammonium acetate in glacial acetic acid under ultrasound irradiation at room temperature results in the formation of 3,4-dihydropyridone derivatives (4a-p) in 85-96% yields. Compared with conventional methods, the main advantages of the present procedure are milder conditions, shorter reaction times and higher yields.
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Cutaneous cryptococcosis due to Cryptococcus gattii in a patient on chronic corticotherapy.
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 01-19-2010
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Cryptococcus gattii causes a form of endemic mycosis that most commonly affects the lungs and central nervous system of immunocompetent patients living in tropical and subtropical areas of the world. Case report. A 66-year-old man who had chronic obstructive pulmonary disease without HIV infection and had been on systemic corticotherapy for several years developed extensive ulceration of the left forearm that was associated with ipsilateral supraclavicular adenomegaly, consequent to infection with Cryptococcus gattii. The patient was treated with fluconazole 400mg/day for eight months, which led to complete healing of the lesion. This case emphasizes that, although rare, C. gattii may cause opportunistic cutaneous-lymphatic infection in patients living in the southeastern region of Brazil who are immunocompromised through chronic corticotherapy.
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3-Hydr-oxy-5,5-dimethyl-2-(2-oxo-propyl)cyclo-hex-2-enone.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 11-10-2009
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The title compound, C(11)H(16)O(3), was obtained by reaction of dimedone, 5,5-dimethylcyclohexane-1,3-dione, and ?-chloro-acetone. The cyclo-hexenone ring exhibits an envelope conformation with puckering amplitudes Q = 0.433?(2) and ? = -109.0?(3)°. The 2-oxopropyl fragment is almost perpendicular to the cyclo-hexa-none ring [dihedral angle = 77.72?(8)°]. In the crystal, the mol-ecules are linked to each other through O-H?O hydrogen bonding, building a chain parallel to the b axis.
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New building block for C(3) symmetry molecules: synthesis of s-triazine-based redox active chromophores.
Org. Lett.
PUBLISHED: 11-04-2009
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A new s-triazine-based C(3) building block, endowed with three phosphonate groups, has been prepared in a simple two-step synthesis starting from p-bromomethylbenzonitrile; the new building block easily undergoes further olefination reactions to afford in a straightforward manner tris(tetrathiafulvalene)- and tris(ferrocene)-1,3,5-triazines.
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Cizolirtine citrate, an effective treatment for symptomatic patients with urinary incontinence secondary to overactive bladder: a pilot dose-finding study.
Eur. Urol.
PUBLISHED: 10-27-2009
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A dose-finding study was performed as the first step in the clinical development of the new drug, cizolirtine citrate.
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