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Find video protocols related to scientific articles indexed in Pubmed.
Preoperative Treatment with Capecitabine, Cetuximab and Radiotherapy for Primary Locally Advanced Rectal Cancer - A Phase II Clinical Trial.
Anticancer Res.
PUBLISHED: 11-05-2014
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To investigate the feasibility and safety of preoperative capecitabine, cetuximab and radiation in patients with MRI-defined locally advanced rectal cancer (LARC, cT3/T4).
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Absorption kinetics of low dose chewable aspirin - implications for acute coronary syndromes.
Eur. J. Clin. Invest.
PUBLISHED: 07-28-2014
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This study describes the implications of the pharmacokinetics of low dose chewable aspirin for acute coronary syndromes. Current guidelines recommend the administration of 162-325 mg aspirin chewing tablets for the treatment of acute myocardial infarction. Although aspirin is widely used and a cornerstone in myocardial infarction, there is no information available on the pharmacokinetics of low doses of chewable aspirin.
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MALDI Orbitrap mass spectrometry for fast and simplified analysis of novel street and designer drugs.
Clin. Chim. Acta
PUBLISHED: 03-13-2014
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New strategies of rapid high-throughput analysis of street drugs without time-consuming sample preparations are necessary due to the massive variety of illicit substances available on the market.
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Empirical multidimensional space for scoring peptide spectrum matches in shotgun proteomics.
J. Proteome Res.
PUBLISHED: 03-13-2014
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Data-dependent tandem mass spectrometry (MS/MS) is one of the main techniques for protein identification in shotgun proteomics. In a typical LC-MS/MS workflow, peptide product ion mass spectra (MS/MS spectra) are compared with those derived theoretically from a protein sequence database. Scoring of these matches results in peptide identifications. A set of peptide identifications is characterized by false discovery rate (FDR), which determines the fraction of false identifications in the set. The total number of peptides targeted for fragmentation is in the range of 10,000 to 20,000 for a several-hour LC-MS/MS run. Typically, <50% of these MS/MS spectra result in peptide-spectrum matches (PSMs). A small fraction of PSMs pass the preset FDR level (commonly 1%) giving a list of identified proteins, yet a large number of correct PSMs corresponding to the peptides originally present in the sample are left behind in the "grey area" below the identity threshold. Following the numerous efforts to recover these correct PSMs, here we investigate the utility of a scoring scheme based on the multiple PSM descriptors available from the experimental data. These descriptors include retention time, deviation between experimental and theoretical mass, number of missed cleavages upon in-solution protein digestion, precursor ion fraction (PIF), PSM count per sequence, potential modifications, median fragment mass error, (13)C isotope mass difference, charge states, and number of PSMs per protein. The proposed scheme utilizes a set of metrics obtained for the corresponding distributions of each of the descriptors. We found that the proposed PSM scoring algorithm differentiates equally or more efficiently between correct and incorrect identifications compared with existing postsearch validation approaches.
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Redundancy in regulation of chondrogenesis in MIA/CD-RAP-deficient mice.
Mech. Dev.
PUBLISHED: 08-30-2013
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Recent in vitro analysis of MIA/CD-RAP-deficient (MIA(-/-)) mesenchymal stem cells revealed altered chondrogenic differentiation, characterised by enhanced proliferation and delayed differentiation. However, adult MIA(-/-) mice develop normally and show only ultrastructural defects of the cartilage but no major abnormalities. We therefore focused, in this study, on chondrogenesis in vivo in MIA(-/-) mouse embryos to reveal potential molecular changes during embryogenesis and possible redundant mechanisms, which explain the almost normal phenotype despite MIA/CD-RAP loss. In situ hybridisation analysis revealed larger expression areas of Col2a1 and Sox9 positive, proliferating chondrocytes at day 15.5 and 16.5 of embryogenesis in MIA(-/-) mice. The initially diminished zone of Col10a1-expressing hypertrophic chondrocytes at day 15.5 was compensated at day 16.5 in MIA(-/-) embryos. Supported by in vitro studies using mesenchymal stem cells, we discovered that chondrogenesis in MIA(-/-) mice is modified by enhanced Sox9, Sox6 and AP-2? expression. Finally, we identified reduced AP1 and CRE activity, analysed by reporter gene- and electrophoretic mobility shift assays, important for redundancy mechanism which rescued delayed hypertrophic differentiation and allows normal development of MIA(-/-) mice. In summary, as observed in other knockout models of molecules important for cartilage development and differentiation, viability and functional integrity is reached by remarkable molecular redundancy in MIA/CD-RAP knockout mice.
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Aminorex, a metabolite of the cocaine adulterant levamisole, exerts amphetamine like actions at monoamine transporters.
Neurochem. Int.
PUBLISHED: 08-02-2013
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Psychostimulants such as amphetamine and cocaine are illicitly used drugs that act on neurotransmitter transporters for dopamine, serotonin or norepinephrine. These drugs can by themselves already cause severe neurotoxicity. However, an additional health threat arises from adulterant substances which are added to the illicit compound without declaration. One of the most frequently added adulterants in street drugs sold as cocaine is the anthelmintic drug levamisole. We tested the effects of levamisole on neurotransmitter transporters heterologously expressed in HEK293 cells. Levamisole was 100 and 300-fold less potent than cocaine in blocking norepinephrine and dopamine uptake, and had only very low affinity for the serotonin transporter. In addition, levamisole did not trigger any appreciable substrate efflux. Because levamisole and cocaine are frequently co-administered, we searched for possible allosteric effects; at 30?M, a concentration at which levamisole displayed already mild effects on norepinephrine transport it did not enhance the inhibitory action of cocaine. Levamisole is metabolized to aminorex, a formerly marketed anorectic drug, which is classified as an amphetamine-like substance. We examined the uptake-inhibitory and efflux-eliciting properties of aminorex and found it to exert strong effects on all three neurotransmitter transporters in a manner similar to amphetamine. We therefore conclude that while the adulterant levamisole itself has only moderate effects on neurotransmitter transporters, its metabolite aminorex may exert distinct psychostimulant effects by itself. Given that the half-time of levamisole and aminorex exceeds that of cocaine, it may be safe to conclude that after the cocaine effect "fades out" the levamisole/aminorex effect "kicks in".
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The effect of a bolus dose of intravenous lidocaine on the minimum alveolar concentration of sevoflurane: a prospective, randomized, double-blinded, placebo-controlled trial.
Anesth. Analg.
PUBLISHED: 06-06-2013
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The anesthetic effect of volatile anesthetics can be quantified by the minimum alveolar concentration (MAC) of the drug that prevents movement in response to a noxious stimulus in 50% of patients. The underlying mechanism regarding how immobilization is achieved by volatile anesthetics is not thoroughly understood, but several drugs affect MAC. In this study, we investigated the effect of a single IV bolus dose of lidocaine on the MAC of sevoflurane in humans.
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The implementation of minimally-invasive esophagectomy does not impact short-term outcome in a high-volume center.
Anticancer Res.
PUBLISHED: 05-07-2013
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Esophagectomy represents the gold standard in the treatment of resectable esophageal cancer. Despite significant improvements in perioperative care, postoperative morbidity and mortality rates remain high. Minimally-invasive surgical techniques introduced to the surgical treatment of esophageal malignancies have been shown to successfully diminish surgical trauma and postoperative morbidity. Aim: In the present report we present the stepwise implementation of minimally-invasive techniques in the treatment of esophageal cancer at a high-volume center and its influence on overall patient outcome.
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Distal Gastrectomy in Pancreaticoduodenectomy is Associated with Accelerated Gastric Emptying, Enhanced Postprandial Release of GLP-1, and Improved Insulin Sensitivity.
J. Gastrointest. Surg.
PUBLISHED: 04-19-2013
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This study aims to investigate the relationship between gastric emptying, postprandial GLP-1 and insulin sensitivity after pancreaticoduodenectomy (PD).
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Melanoma inhibitory activity promotes melanoma development through activation of YBX1.
Pigment Cell Melanoma Res
PUBLISHED: 03-01-2013
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Melanoma inhibitory activity (MIA), a small soluble secreted protein, is functionally important for progression of malignant melanoma. We recently revealed that p54(nrb) acts as a mediator of MIA action. In this study, we characterize the transcriptional regulation of p54(nrb) by MIA to explain MIAs molecular action. We identified one highly conserved region in the p54(nrb) promoter that is necessary and sufficient for MIA-dependent activation. Functional promoter analysis identified the transcription factor YBX1 as the mediator of MIA activation of p54(nrb) transcription. We screened the genome for further potential MIA-regulated genes carrying the element in their promoter regions. Integrating our sequence data with expression data from human melanomas identified a list of 23 potential MIA-YBX1 targets in melanomas. In summary, we present for the first time effects of MIA on transcriptional regulation. Uncovering new potential downstream effectors working via activation of YBX1 supports the important role of MIA in melanoma.
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YBX1 Is a Modulator of MIA/CD-RAP-Dependent Chondrogenesis.
PLoS ONE
PUBLISHED: 01-01-2013
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MIA/CD-RAP is a small, secreted protein involved in cartilage differentiation and melanoma progression. We recently revealed that p54(nrb) acts as a mediator of MIA/CD-RAP action to promote chondrogenesis and the progression of malignant melanoma. As the molecular mechanism of MIA/CD-RAP action in cartilage has not been defined in detail until now, we aimed to understand the regulation of p54(nrb) transcription in chondrogenesis. We concentrated on the previously described MIA/CD-RAP-dependent regulatory region in the p54(nrb) promoter and characterized the transcriptional regulation of p54(nrb) by MIA/CD-RAP in cartilage. A series of truncated p54(nrb) promoter constructs and mutagenesis analysis revealed that the transcription factor YBX1, which has not been investigated in chondrogenesis thus far, is the mediator of MIA/CD-RAP dependent activation of p54(nrb) transcription. A systematic analysis of genes carrying this binding site in their promoter region revealed further potential MIA/CD-RAP-regulated genes that have been implicated in cartilage differentiation. In summary, we described the effects of MIA/CD-RAP on transcriptional regulation in chondrocytes. Understanding the regulation of p54(nrb) via YBX1 contributes to the understanding of chondrogenesis. Uncovering new downstream effectors that function via the activation of YBX1 supports the important role of MIA/CD-RAP in these processes.
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p54nrb is a new regulator of progression of malignant melanoma.
Carcinogenesis
PUBLISHED: 06-03-2011
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Nuclear RNA-binding protein p54(nrb) and its murine homolog NonO are known to be involved in a variety of nuclear processes including transcription and RNA processing. Melanoma inhibitory activity (MIA) has been shown to play an essential role in the progression of malignant melanoma and to influence melanoma-associated molecules and pathways in the early tumor formation steps. Interestingly, recent studies suggest that MIA is a regulator of p54(nrb). Here, we show that p54(nrb) is strongly expressed and localized in the nucleus of both melanoma cell lines and melanoma tissue samples compared with normal human melanocytes or normal skin, respectively. Furthermore, all tested melanoma cell lines revealed strong p54(nrb) promoter activity. Treatment with MIA-specific small interfering RNAs showed an influence of MIA on p54(nrb) expression on both messenger RNA (mRNA) and protein level. Knockdown of p54(nrb) protein in melanoma cell lines led to reduced proliferation rates and to a strong decrease in their migratory potential. In addition, attachment to laminin and poly-l-lysine was significantly increased. We could identify Connexin-43 (Cx-43) as a downstream target molecule of p54(nrb) as knockdown of p54(nrb) resulted in enhanced Cx-43 mRNA and protein levels. As a confirmation of these findings, melanoma cell lines showed very low Cx-43 expression levels compared with melanocytes. Our results demonstrate that p54(nrb) is highly expressed in malignant melanoma and, as a MIA target molecule, it seems to be involved in the development and progression of malignant melanoma.
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Extended indications for nipple-sparing mastectomy.
Breast J
PUBLISHED: 03-31-2011
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Ablative breast cancer surgery still includes the routine excision of the nipple-areola complex (NAC). Nipple-sparing mastectomy (NSM) removes the breast tissue leaving no or little retroareolar ductal tissue but preserves the entire skin of the breast and the NAC. There is some consensus that NSM might be an oncologically safe option for patients with small and peripherally located tumors and probably for high-risk patients with prophylactic mastectomy. Several studies demonstrated that NSM may be feasible even in patients with large centrally located tumors or multicentric invasive carcinoma. So far, no generally applicable indications for NSM have been defined because long-term data are still limited. However, from our review of the literature obtained from a MEDLINE search (2003-2009) we conclude that the range of indications for NSM needs not to be limited to small peripheral tumors or to prophylactic treatment.
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Multisite analytical evaluation of the Abbott ARCHITECT cyclosporine assay.
Ther Drug Monit
PUBLISHED: 03-11-2010
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The objective of this study was to evaluate the analytical performance of the Abbott ARCHITECT Cyclosporine (CsA) immunoassay in 7 clinical laboratories in comparison to liquid chromatography/tandem mass spectrometry (LC/MS/MS), Abbott TDx, Cobas Integra 800, and the Dade Dimension Xpand immunoassay. The ARCHITECT assay uses a whole blood specimen, a pretreatment step with organic reagents to precipitate proteins and extract the drug, followed by a 2-step automated immunoassay with magnetic microparticles coated with anti-CsA antibody and an acridinium-CsA tracer. Imprecision testing at the 7 evaluation sites gave a range of total % coefficient of variations of 7.5%-12.2% at 87.5 ng/mL, 6.6%-14.3% at 411 ng/mL, and 5.2%-10.7% at 916 ng/mL. The lower limit of quantification ranged from 12 to 20 ng/mL. Purified CsA metabolites AM1, AM1c, AM4N, AM9, and AM19 were tested in whole blood by the ARCHITECT assay and showed minimal cross-reactivity at all 7 sites. In particular, AM1 and AM9 cross-reactivity in the ARCHITECT assay, ranged from -2.5% to 0.2% and -0.8% to 2.2%, respectively, and was significantly lower than for the TDx assay, in which the values were 3.2% and 16.1%, respectively. Comparable testing of metabolites in the Dade Dimension Xpand assay at 2 evaluation sites showed cross-reactivity to AM4N (6.4% and 6.8%) and AM9 (2.6% and 3.6%) and testing on the Roche Integra 800 showed cross-reactivity to AM1c (2.4%), AM9 (10.7%), and AM19 (2.8%). Cyclosporine International Proficiency Testing Scheme samples, consisting of both pooled specimens from patients receiving CsA therapy as well as whole-blood specimens supplemented with CsA, were tested by the ARCHITECT assay at 6 sites and showed an average bias of -24 to -58 ng/mL versus LC/MSMS CsA and -2 to -37 ng/mL versus AxSYM CsA. Studies were performed with the ARCHITECT CsA assay on patient specimens with the following results: ARCHITECT CsA assay versus LC/MSMS, average bias of 31 ng/mL; ARCHITECT versus the Dade Dimension assay (4 sites), average biases of -7 to -228 ng/mL; ARCHITECT versus AxSYM and TDx, average biases of -4 and -53 ng/mL, respectively. Spearman correlation coefficients were >or=0.89. The ARCHITECT CsA assay has significantly reduced CsA metabolite interference relative to other immunoassays and is a convenient and sensitive semiautomated method to measure CsA in whole blood.
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The effects of low-molecular-weight heparin at two different dosages on thrombin generation in cancer patients. A randomised controlled trial.
Thromb. Haemost.
PUBLISHED: 02-26-2010
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Non-surgical cancer patients are at high thrombotic risk. We hypothesised that the prothrombotic state is reflected by elevated thrombin generation and can be mitigated by increasing the low-molecular-weight heparin (LMWH) dose. Non-surgical cancer patients were randomised to enoxaparin 40 or 80 mg. D-dimer, prothrombin fragment F1+2 (F1+2) and peak thrombin (PT) were measured 2, 4, 6 hours (h) after LMWH (day 1) and daily for 4 days. A total of 22 and 27 patients received enoxaparin 40 and 80 mg, respectively. D-dimer and F1+2 moderately decreased after 6 h in both groups. After enoxaparin 80 mg, D-dimer baseline levels [median (quartiles)] decreased from day 1 to 4 [1054.9 (549.5, 2714.0) vs. 613.0 (441.1, 1793.5) ng/ml] (p<0.0001), while no difference was seen after 40 mg. Baseline PT levels [median (quartiles)] were 426.2 nM (347.3, 542.3) (40 mg) and 394.0 nM (357.1, 448.8) (80 mg). After 80 mg, PT significantly decreased to 112.4 nM (68.5, 202.4), 57.1 nM (38.0, 101.2) and 43.6 nM (23.4, 112.8) after 2, 4 and 6 h, which was lower than after 40 mg (p=0.003). After 80 mg, PT decreased from day 1 to 4 [358.6 nM (194.2, 436.6); p=0.06] while no difference was seen after 40 mg. In conclusion, in cancer patients coagulation activation and thrombin generation is substantially increased. Peak thrombin levels are sensitive to the anticoagulant effects of LMWH at different dosages. The prothrombotic state is substantially attenuated by higher LMWH doses.
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Modulation of cartilage differentiation by melanoma inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP).
Exp. Mol. Med.
PUBLISHED: 02-19-2010
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Melanoma inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP) is a small soluble protein secreted from malignant melanoma cells and from chondrocytes. Recently, we revealed that MIA/CD-RAP can modulate bone morphogenetic protein (BMP)2-induced osteogenic differentiation into a chondrogenic direction. In the current study we aimed to find the molecular details of this MIA/CD-RAP function. Direct influence of MIA on BMP2 by protein-protein-interaction or modulating SMAD signaling was ruled out experimentally. Instead, we revealed inhibition of ERK signaling by MIA/CD-RAP. This inhibition is regulated via binding of MIA/CD-RAP to integrin alpha5 and abolishing its activity. Active ERK signaling is known to block chondrogenic differentiation and we revealed induction of aggrecan expression in chondrocytes by treatment with MIA/CD-RAP or PD098059, an ERK inhibitor. In in vivo models we could support the role of MIA/CD-RAP in influencing osteogenic differentiation negatively. Further, MIA/CD-RAP-deficient mice revealed an enhanced calcified cartilage layer of the articular cartilage of the knee joint and disordered arrangement of chondrocytes. Taken together, our data indicate that MIA/CD-RAP stabilizes cartilage differentiation and inhibits differentiation into bone potentially by regulating signaling processes during differentiation.
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Subcutaneous mastectomy with conservation of the nipple-areola skin: broadening the indications.
Ann. Surg.
PUBLISHED: 07-30-2009
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Numerous authors take multiple predictive factors into account to decide whether or not the nipple-areola complex (NAC) can be conserved during mastectomy. These factors include the tumor-nipple distance, tumor size, axillary lymph node status, and lymphovascular invasion. Thus only a very limited percentage of patients can keep their NAC. If the breast gland tissue and all milk ducts can be separated completely from the nipple-areola skin (NA-skin) during subcutaneous mastectomy (SCM), conservation of the NA-skin is feasible even in the case of large, central, and retroareolar tumors.
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Temporary placement of self-expanding oesophageal stents as bridging for neo-adjuvant therapy.
Ann. Surg. Oncol.
PUBLISHED: 05-25-2009
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Placement of self-expanding stents is an effective palliation for dysphagia in non-resectable oesophageal or proximal gastric cancer. The aim of this analysis was to assess the efficacy of temporary stent placement for dysphagia relief during neo-adjuvant treatment for locally advanced disease.
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Multi-site analytical evaluation of a chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the Abbott ARCHITECT analyzer.
Clin. Biochem.
PUBLISHED: 03-05-2009
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This study evaluated a new chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the ARCHITECT analyzer.
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Multi-site analytical evaluation of the Abbott ARCHITECT tacrolimus assay.
Ther Drug Monit
PUBLISHED: 03-05-2009
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The objective of this study was to evaluate the analytical performance of the Abbott ARCHITECT Tacrolimus immunoassay. Proficiency panels and specimens from a population of organ transplant recipients were analyzed in 6 clinical laboratories in Europe and the United States, and the results were compared with other methods. The ARCHITECT assay requires a whole blood specimen pretreatment step with methanol/zinc sulfate to precipitate protein and extract the drug, followed by a 30-minute immunoassay using anti-tacrolimus antibody-coated paramagnetic microparticles and an acridinium-tacrolimus tracer. The assay was free from hematocrit interference in the range 25%-55% and from interference by extremes of cholesterol, triglycerides, bilirubin, total protein, and uric acid. The total percent of coefficient of variations of the assay were 4.9%-7.6% at 3 ng/mL, 2.9%-4.6% at 8.6 ng/mL, and 3.1%-8.2% at 15.5 ng/mL. Limit of detection was < or =0.5 ng/mL and limit of quantification (LOQ) ranged from 0.69 to 1.07 ng/mL across the 6 sites (based on the upper 95% confidence interval concentrations). The 2007 European Consensus Conference on Tacrolimus Optimization recommended the use of assay methods with an LOQ around 1 ng/mL, based upon the need to measure trough tacrolimus blood concentrations precisely down to 3 ng/mL during low-dose tacrolimus regimens. Tacrolimus International Proficiency Testing Scheme samples were measured by the ARCHITECT immunoassay at 5 sites and showed an average bias of -0.28 to +0.85 ng/mL versus IMx Tacrolimus II immunoassay historical values and -0.21 to +0.68 ng/mL versus liquid chromatography/tandem mass spectrometry (LC-MSMS) Tacrolimus historical values. Method comparison studies were performed with the ARCHITECT Tacrolimus immunoassay on patient specimens with the following results: ARCHITECT Tacrolimus assay versus the Abbott IMx Tacrolimus II immunoassay (4 sites) yielded average biases between -0.94 and +0.26 ng/mL; ARCHITECT assay versus the Dade Dimension Tacrolimus immunoassay (2 sites) yielded average biases of -0.46 and +0.11 ng/mL; and ARCHITECT assay versus LC-MSMS methods at 2 sites yielded average biases of +0.51 and +1.63 ng/mL. Spearman correlation coefficients were >/=0.90 on all method comparisons. The ARCHITECT Tacrolimus assay is a semiautomated, robust, and highly sensitive immunoassay, representing an alternative approach for laboratories not equipped with LC-MSMS, and meets the 1 ng/mL recommendation of LOQ by the European Consensus Conference on Tacrolimus Optimization.
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Beta endovascular brachytherapy using CO2-filled centering catheter for treatment of recurrent superficial femoropopliteal artery disease.
Cardiovasc Revasc Med
PUBLISHED: 02-16-2009
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Recurrent disease (restenosis) after endovascular treatment of the superficial femoral artery (SFA) remains a major problem. We evaluated the efficacy of beta-endovascular brachytherapy using the CORONA centering catheter in patients with SFA restenosis in a single-arm Phase II trial.
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A combined approach using transporter-flux assays and mass spectrometry to examine psychostimulant street drugs of unknown content.
ACS Chem Neurosci
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The illicit consumption of psychoactive compounds may cause short and long-term health problems and addiction. This is also true for amphetamines and cocaine, which target monoamine transporters. In the recent past, an increasing number of new compounds with amphetamine-like structure such as mephedrone or 3,4-methylenedioxypyrovalerone (MDPV) entered the market of illicit drugs. Subtle structural changes circumvent legal restrictions placed on the parent compound. These novel drugs are effectively marketed "designer drugs" (also called "research chemicals") without any knowledge of the underlying pharmacology, the potential harm or a registration of the manufacturing process. Accordingly new entrants and their byproducts are identified postmarketing by chemical analysis and their pharmacological properties inferred by comparison to compounds of known structure. However, such a heuristic approach fails, if the structures diverge substantially from a known derivative. In addition, the understanding of structure-activity relations is too rudimentary to predict detailed pharmacological activity. Here, we tested a combined approach by examining the composition of street drugs using mass spectrometry and by assessing the functional activity of their constituents at the neuronal transporters for dopamine, serotonin, and norepinephrine. We show that this approach is superior to mere chemical analysis in recognizing novel and potentially harmful street drugs.
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Simultaneous determination of acetylsalicylic acid and salicylic acid in human plasma by isocratic high-pressure liquid chromatography with post-column hydrolysis and fluorescence detection.
Biomed. Chromatogr.
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A selective, sensitive and rapid high-performance liquid chromatography method with post-column hydrolysis and fluorescence detection was developed for the simultaneous quantification of acetylsalicylic acid and its metabolite salicylic acid in human plasma. Following the addition of 2-hydroxy-3-methoxybenzoic acid as internal standard and simple protein precipitation with acetonitrile, the analytes were separated on a ProntoSIL 120 C18 ace-EPS column (150 × 2 mm, 3 µm) protected by a C8 guard column (5 µm). The mobile phase, 10 mm formic acid in water (pH 2.9) and acetonitrile (70:30, v/v), was used at a flow rate of 0.35 mL/min. After on-line post-column hydrolysis of acetylsalicylic acid (ASA) to salicylic acid (SA) by addition of alkaline solution, the analytes were measured at 290 nm (?ex ) and 400 nm (?em ). The method was linear in the concentration ranges between 0.05 and 20 ng/?L for both ASA and SA with a lower limit of quantification of 25 pg/?L for SA and 50 pg/?L for ASA. The limit of detection was 15 pg/?L for SA and 32.5 pg/?L for ASA. The analysis of ASA and SA can be carried out within 8 min; therefore this method is suitable for measuring plasma concentrations of salicylates in clinical routine.
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Impact of the Reconstruction Method on Delayed Gastric Emptying After Pylorus-Preserving Pancreaticoduodenectomy: A Prospective Randomized Study.
World J Surg
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Delayed gastric emptying (DGE) is of considerable concern in patients undergoing pylorus-preserving pancreaticoduodenectomy (PPPD). Prolonged hospital stay, increased cost, and decreased quality of life add on to interventions needed to treat DGE. This study was conducted to determine if performing duodenojejunostomy via the antecolic rather than the retrocolic route improved incidence of DGE.
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What is Visualize?

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

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

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

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