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Find video protocols related to scientific articles indexed in Pubmed.
Evaluation of Pyrosequencing for Detecting Extensively Drug-resistant Tuberculosis (XDR-TB) in Clinical Isolates from Four High-burden Countries.
Antimicrob. Agents Chemother.
PUBLISHED: 11-05-2014
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Reliable molecular diagnostics, which detect specific mutations associated with drug resistance, are promising technologies for the rapid identification and monitoring of drug resistance in Mycobacterium tuberculosis (Mtb) isolates. Pyrosequencing (PSQ) has the ability to detect mutations associated with first- and second-line anti-tuberculosis (TB) drugs, with the additional advantage of being rapidly adaptable for the identification of new mutations. The aim of this project was to evaluate the performance of PSQ in predicting phenotypic drug resistance in multi- and extensively drug-resistant tuberculosis (M/XDR-TB) clinical isolates from India, South Africa, Moldova and the Philippines.
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Magnetic resonance elastography predicts advanced fibrosis in patients with nonalcoholic fatty liver disease: A prospective study.
Hepatology
PUBLISHED: 08-08-2014
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Retrospective studies have shown that two-dimensional magnetic resonance elastography (2D-MRE), a novel MR method for assessment of liver stiffness, correlates with advanced fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). Prospective data on diagnostic accuracy of 2D-MRE in the detection of advanced fibrosis in NAFLD are needed. The aim of this study is to prospectively assess the diagnostic accuracy of 2D-MRE, a noninvasive imaging biomarker, in predicting advanced fibrosis (stage 3 or 4) in well-characterized patients with biopsy-proven NAFLD. This is a cross-sectional analysis of a prospective study including 117 consecutive patients (56% women) with biopsy-proven NAFLD who underwent a standardized research visit: history, exam, liver biopsy assessment (using the nonalcoholic steatohepatitis Clinical Research Network histological scoring system), and 2D-MRE from 2011 to 2013. The radiologist and pathologist were blinded to clinical and pathology/imaging data, respectively. Receiver operating characteristics (ROCs) were examined to assess the diagnostic test performance of 2D-MRE in predicting advanced fibrosis. The mean (± standard deviation) of age and body mass index was 50.1 (± 13.4) years and 32.4 (± 5.0) kg/m(2) , respectively. The median time interval between biopsy and 2D-MRE was 45 days (interquartile range: 50 days). The number of patients with fibrosis stages 0, 1, 2, 3, and 4 was 43, 39, 13, 12, and 10, respectively. The area under the ROC curve for 2D-MRE discriminating advanced fibrosis (stage 3-4) from stage 0-2 fibrosis was 0.924 (P?3.63 kPa had a sensitivity of 0.86 (95% confidence interval [CI]: 0.65-0.97), specificity of 0.91 (95% CI: 0.83-0.96), positive predictive value of 0.68 (95% CI: 0.48-0.84), and negative predictive value of 0.97 (95% CI: 0.91-0.99). Conclusions: MRE is accurate in predicting advanced fibrosis and may be utilized for noninvasive diagnosis of advanced fibrosis in patients with NAFLD. (Hepatology 2014).
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ERG-APLNR axis controls pulmonary venule endothelial proliferation in pulmonary veno-occlusive disease.
Circulation
PUBLISHED: 07-25-2014
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Pulmonary veno-occlusive disease is caused by excessive cell proliferation and fibrosis, which obliterate the lumen of pulmonary venules, leading to pulmonary hypertension, right ventricular failure, and death. This condition has no effective treatment and a 5-year survival of <5%. Understanding the mechanism of this disease and designing effective therapies are urgently needed.
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Right heart dysfunction in heart failure with preserved ejection fraction.
Eur. Heart J.
PUBLISHED: 05-31-2014
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Right heart function is not well characterized in patients with heart failure and preserved ejection fraction (HFpEF). The goal of this study was to examine the haemodynamic, clinical, and prognostic correlates of right ventricular dysfunction (RVD) in HFpEF.
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Molecular diagnosis of tuberculosis and drug resistance.
Clin. Lab. Med.
PUBLISHED: 05-27-2014
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Molecular drug susceptibility testing (MDST) provides rapid diagnosis of tuberculosis (TB) and detection of drug resistance with commendable sensitivity and specificity. MDST reduces unnecessary isolation or treatment, when a negative result for TB is obtained. Because of the possibility of false detection of rifampin resistance by probe-based MDST, confirmation by sequencing is recommended, especially in regions where the prevalence of resistance is low. Revealing mutation identity by sequencing offers opportunities to study drug minimum inhibitory concentrations for each mutation. Such information enables prediction of resistance levels, and may be helpful in formulating optimal regimens, when treatment options are limited.
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Resting ventricular-vascular function and exercise capacity in heart failure with preserved ejection fraction: a RELAX trial ancillary study.
Circ Heart Fail
PUBLISHED: 05-15-2014
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Exercise intolerance is a hallmark of heart failure, but factors associated with impaired exercise capacity in heart failure with preserved ejection fraction are unclear. We hypothesized that in heart failure with preserved ejection fraction, the severity of resting ventricular and vascular dysfunction are associated with impairment in exercise tolerance as assessed by peak oxygen consumption.
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The Global Consortium for Drug-resistant Tuberculosis Diagnostics (GCDD): design of a multi-site, head-to-head study of three rapid tests to detect extensively drug-resistant tuberculosis.
Trials
PUBLISHED: 05-06-2014
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Drug-resistant tuberculosis (DR-TB) remains a threat to global public health, owing to the complexity and delay of diagnosis and treatment. The Global Consortium for Drug-resistant Tuberculosis Diagnostics (GCDD) was formed to develop and evaluate assays designed to rapidly detect DR-TB, so that appropriate treatment might begin more quickly. This paper describes the methodology employed in a prospective cohort study for head-to-head assessment of three different rapid diagnostic tools.
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The intestinal microbiome of fish under starvation.
BMC Genomics
PUBLISHED: 03-31-2014
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Starvation not only affects the nutritional and health status of the animals, but also the microbial composition in the host's intestine. Next-generation sequencing provides a unique opportunity to explore gut microbial communities and their interactions with hosts. However, studies on gut microbiomes have been conducted predominantly in humans and land animals. Not much is known on gut microbiomes of aquatic animals and their changes under changing environmental conditions. To address this shortcoming, we determined the microbial gene catalogue, and investigated changes in the microbial composition and host-microbe interactions in the intestine of Asian seabass in response to starvation.
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A randomized pilot study of aortic waveform guided therapy in chronic heart failure.
J Am Heart Assoc
PUBLISHED: 03-22-2014
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Medication treatment decisions in heart failure (HF) are currently informed by measurements of brachial artery pressure, but ventricular afterload is more accurately represented by central aortic pressure, which differs from brachial pressure. We sought to determine whether aggressive titration of vasoactive medicines beyond goal-directed heart failure medical therapy (GDMT) based upon aortic pressure improves exercise capacity and cardiovascular structure-function.
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Receipt of glucocorticoid monotherapy among Medicare beneficiaries with rheumatoid arthritis.
Arthritis Care Res (Hoboken)
PUBLISHED: 02-11-2014
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Using disease-modifying antirheumatic drugs (DMARDs) improves outcomes in rheumatoid arthritis (RA) and is a nationally endorsed quality measure. We investigated the prevalence and predictors of receiving glucocorticoids alone for the treatment of RA in a nationwide sample of Medicare beneficiaries.
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Pyrosequencing for rapid detection of extensively drug-resistant Mycobacterium tuberculosis in clinical isolates and clinical specimens.
J. Clin. Microbiol.
PUBLISHED: 01-31-2014
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Treating extensively drug-resistant (XDR) tuberculosis (TB) is a serious challenge. Culture-based drug susceptibility testing (DST) may take 4 weeks or longer from specimen collection to the availability of results. We developed a pyrosequencing (PSQ) assay including eight subassays for the rapid identification of Mycobacterium tuberculosis complex (MTBC) and concurrent detection of mutations associated with resistance to drugs defining XDR TB. The entire procedure, from DNA extraction to the availability of results, was accomplished within 6 h. The assay was validated for testing clinical isolates and clinical specimens, which improves the turnaround time for molecular DST and maximizes the benefit of using molecular testing. A total of 130 clinical isolates and 129 clinical specimens were studied. The correlations between the PSQ results and the phenotypic DST results were 94.3% for isoniazid, 98.7% for rifampin, 97.6% for quinolones (ofloxacin, levofloxacin, or moxifloxacin), 99.2% for amikacin, 99.2% for capreomycin, and 96.4% for kanamycin. For testing clinical specimens, the PSQ assay yielded a 98.4% sensitivity for detecting MTBC and a 95.8% sensitivity for generating complete sequencing results from all subassays. The PSQ assay was able to rapidly and accurately detect drug resistance mutations with the sequence information provided, which allows further study of the association of drug resistance or susceptibility with each mutation and the accumulation of such knowledge for future interpretation of results. Thus, reporting of false resistance for mutations known not to confer resistance can be prevented, which is a significant benefit of the assay over existing molecular diagnostic methods endorsed by the World Health Organization.
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Reciprocal occupancy of BCL6 and STAT5 on Growth Hormone target genes: contrasting transcriptional outcomes and promoter-specific roles of p300 and HDAC3.
Mol. Cell. Endocrinol.
PUBLISHED: 01-29-2014
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Expression of the Growth Hormone (GH)-stimulated gene Socs2 (Suppressor of Cytokine Signaling 2) is mediated by the transcription activator STAT5 (Signal Transducer and Activator of Transcription 5) and the transcription repressor BCL6 (B-Cell Lymphoma 6). ChIP-Sequencing identified Cish (Cytokine-Inducible SH2-containing protein) and Bcl6 as having similar patterns of reciprocal occupancy by BCL6 and STAT5 in response to GH, though GH stimulates Cish and inhibits Bcl6 expression. The co-activator p300 occupied Socs2, Cish and Bcl6 promoters, and enhanced STAT5-mediated activation of Socs2 and Cish. In contrast, on Bcl6, p300 functioned as a repressor and inhibited in conjunction with STAT5 or BCL6. The co-repressor HDAC3 (Histone deacetylase 3) inhibited the Socs2, Cish and Bcl6 promoters in the presence of STAT5. Thus transcriptional outcomes on GH-regulated genes occupied by BCL6 and STAT5 are determined in a promoter-specific fashion by co-regulatory proteins which mediate the distinction between activating and repressive transcription factors.
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A secreted tyrosine kinase acts in the extracellular environment.
Cell
PUBLISHED: 01-13-2014
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Although tyrosine phosphorylation of extracellular proteins has been reported to occur extensively in vivo, no secreted protein tyrosine kinase has been identified. As a result, investigation of the potential role of extracellular tyrosine phosphorylation in physiological and pathological tissue regulation has not been possible. Here, we show that VLK, a putative protein kinase previously shown to be essential in embryonic development, is a secreted protein kinase, with preference for tyrosine, that phosphorylates a broad range of secreted and ER-resident substrate proteins. We find that VLK is rapidly and quantitatively secreted from platelets in response to stimuli and can tyrosine phosphorylate coreleased proteins utilizing endogenous as well as exogenous ATP sources. We propose that discovery of VLK activity provides an explanation for the extensive and conserved pattern of extracellular tyrosine phosphophorylation seen in vivo, and extends the importance of regulated tyrosine phosphorylation into the extracellular environment.
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Cell Fate Decisions in Malignant Hematopoiesis: Leukemia Phenotype Is Determined by Distinct Functional Domains of the MN1 Oncogene.
PLoS ONE
PUBLISHED: 01-01-2014
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Extensive molecular profiling of leukemias and preleukemic diseases has revealed that distinct clinical entities, like acute myeloid (AML) and T-lymphoblastic leukemia (T-ALL), share similar pathogenetic mutations. It is not well understood how the cell of origin, accompanying mutations, extracellular signals or structural differences in a mutated gene determine the phenotypic identity of leukemias. We dissected the functional aspects of different protein regions of the MN1 oncogene and their effect on the leukemic phenotype, building on the ability of MN1 to induce leukemia without accompanying mutations. We found that the most C-terminal region of MN1 was required to block myeloid differentiation at an early stage, and deletion of an extended C-terminal region resulted in loss of myeloid identity and cell differentiation along the T-cell lineage in vivo. Megakaryocytic/erythroid lineage differentiation was blocked by the N-terminal region. In addition, the N-terminus was required for proliferation and leukemogenesis in vitro and in vivo through upregulation of HoxA9, HoxA10 and Meis2. Our results provide evidence that a single oncogene can modulate cellular identity of leukemic cells based on its active gene regions. It is therefore likely that different mutations in the same oncogene may impact cell fate decisions and phenotypic appearance of malignant diseases.
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Deficiency of the transcriptional repressor B cell lymphoma 6 (Bcl6) is accompanied by dysregulated lipid metabolism.
PLoS ONE
PUBLISHED: 01-01-2014
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The transcriptional repressor B-cell Lymphoma 6 (Bcl6) was recently identified in a profile of genes regulated in adipocytes, suggesting a relationship between Bcl6 and metabolic regulation. As a representative target gene repressed by Bcl6, Suppressor of Cytokine Signaling (Socs) 2 expression was elevated in Bcl6 deficient (KO) mice, including metabolic tissues liver, adipose tissue and muscle, as well as in spleen and thymus. Bcl6 occupied the Socs2 promoter in wild-type, but not Bcl6 KO mice, suggesting direct regulation of Socs2 by Bcl6 in vivo. Mice deficient in Bcl6 were found to exhibit multiple features of dysregulated lipid metabolism. Adipose tissue mass was dramatically reduced or absent in Bcl6 KO mice. Further, hepatic and serum triglycerides were low. Bcl6 deficiency was accompanied by decreased hepatic expression of Stearoyl-CoA desaturase 1 (Scd1) and Fatty acid synthase (Fasn) genes which encode lipogenic enzymes. Expression of the gene for the transcription factor Carbohydrate-Responsive Element Binding Protein (Chrebp), which regulates expression of lipogenic genes, was also reduced in liver of Bcl6 KO mice. Bcl6 deficiency disrupted fasting-induced increases in hepatic triglyceride deposition, but not decreases in lipogenic gene expression. Taken together, these findings suggest that in addition to its well-recognized roles in immune regulation, Bcl6 plays a role in regulatory events of lipid metabolism, and that in the absence of Bcl6, lipid metabolism in liver and adipose tissue is dysregulated.
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Predicting Extensively Drug-resistant Tuberculosis (XDR-TB) Phenotypes with Genetic Mutations.
J. Clin. Microbiol.
PUBLISHED: 12-18-2013
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Molecular diagnostics, based on detection of mutations conferring resistance are promising technologies for rapidly detecting multi/extensively drug resistant tuberculosis (M/XDR-TB), but large studies of mutations as markers of resistance are rare. The Global Consortium for Drug-resistant TB Diagnostics analyzed 417 Mtb isolates from multinational sites with high prevalence of drug resistance to determine sensitivity and specificity of mutations associated with M/XDR-TB and inform development of rapid diagnostics. We collected M/XDR-TB isolates from regions of high TB burden in India, Moldova, Philippines and South Africa. Isolates underwent standardized phenotypic drug susceptibility testing (DST) to isoniazid (INH), rifampin (RIF), moxifloxacin (MOX), ofloxacin (OFX), amikacin (AMK), kanamycin (KAN) and capreomycin (CAP) using MGIT 960 and WHO recommended critical concentrations. Seven genes (katG, inhA, rpoB, gyrA, gyrB, rrs, eis and tlyA) were sequenced using Sanger sequencing. Three hundred seventy isolates were INH(R), 356 RIF(R), 292 MOX(R)/OFX(R), 230 AMK(R), 219 CAP(R) and 286 KAN(R). Four SNPs in katG/inhA had combined sensitivity of 96% and specificity of 97-100% for detection of INH(R). Eleven SNPs in rpoB had combined sensitivity of 98% for RIF(R). Eight SNPs in gyrA88-94 had sensitivity of 90% for MOX(R)/OFX(R). The rrs 1401/1484 SNPs had 89-90% sensitivity for detecting AMK(R)/CAP(R), but 71% sensitivity for KAN(R). Adding eis promoter SNPs increased sensitivity for detecting AMK(R) to 93% and KAN(R) to 91%. Approximately 30 SNPs in six genes predicted clinically relevant XDR-TB phenotypes with 90-98% sensitivity and almost 100% specificity.
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Insulin Resistance Increases MRI-Estimated Pancreatic Fat in Nonalcoholic Fatty Liver Disease and Normal Controls.
Gastroenterol Res Pract
PUBLISHED: 09-04-2013
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Background. Ectopic fat deposition in the pancreas and its relationship with hepatic steatosis and insulin resistance have not been compared between patients with nonalcoholic fatty liver disease (NAFLD) and healthy controls. Aim. Using a novel magnetic resonance imaging (MRI) based biomarker, the proton-density-fat-fraction (MRI-PDFF), we compared pancreatic fat content in patients with biopsy-proven NAFLD to healthy controls and determined whether it is associated with insulin resistance and liver fat content. Methods. This nested case-control study was derived from two prospective studies including 43 patients with biopsy-proven NAFLD and 49 healthy controls who underwent biochemical testing and MRI. Results. Compared to healthy controls, patients with NAFLD had significantly higher pancreatic MRI-PDFF (3.6% versus 8.5%, P value <0.001), and these results remained consistent in multivariable-adjusted models including age, sex, body mass index, and diabetes (P value =0.03). We found a strong correlation between hepatic and pancreatic MRI-PDFF (Spearman correlation, P = 0.57, P value <0.001). Participants with increased insulin resistance determined by homeostatic-model-of-insulin-resistance (HOMA-IR) greater than 2.5 had higher pancreatic (7.3% versus 4.5%, P value =0.015) and liver (13.5% versus 4.0%, P value <0.001) MRI-PDFF. Conclusion. Patients with NAFLD have greater pancreatic fat than normal controls. Insulin resistance is associated with liver and pancreatic fat accumulation.
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Autophagy promotes primary ciliogenesis by removing OFD1 from centriolar satellites.
Nature
PUBLISHED: 08-29-2013
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The primary cilium is a microtubule-based organelle that functions in sensory and signalling pathways. Defects in ciliogenesis can lead to a group of genetic syndromes known as ciliopathies. However, the regulatory mechanisms of primary ciliogenesis in normal and cancer cells are incompletely understood. Here we demonstrate that autophagic degradation of a ciliopathy protein, OFD1 (oral-facial-digital syndrome 1), at centriolar satellites promotes primary cilium biogenesis. Autophagy is a catabolic pathway in which cytosol, damaged organelles and protein aggregates are engulfed in autophagosomes and delivered to lysosomes for destruction. We show that the population of OFD1 at the centriolar satellites is rapidly degraded by autophagy upon serum starvation. In autophagy-deficient Atg5 or Atg3 null mouse embryonic fibroblasts, OFD1 accumulates at centriolar satellites, leading to fewer and shorter primary cilia and a defective recruitment of BBS4 (Bardet-Biedl syndrome 4) to cilia. These defects are fully rescued by OFD1 partial knockdown that reduces the population of OFD1 at centriolar satellites. More strikingly, OFD1 depletion at centriolar satellites promotes cilia formation in both cycling cells and transformed breast cancer MCF7 cells that normally do not form cilia. This work reveals that removal of OFD1 by autophagy at centriolar satellites represents a general mechanism to promote ciliogenesis in mammalian cells. These findings define a newly recognized role of autophagy in organelle biogenesis.
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The effectiveness of the promotion of newborn hearing screening in Taiwan.
Int. J. Pediatr. Otorhinolaryngol.
PUBLISHED: 08-22-2013
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Hearing is a critical ability for the development of a childs speech and language. Many studies in different countries have shown the universal newborn hearing screening and early intervention has greatly reduced the negative impact caused by congenital hearing loss. The first universal newborn hearing screening program in Taiwan took place in MacKay Memorial Hospital in 1998 and was subsequently endorsed by the government. The incidence of bilateral congenital hearing impairment in Taiwan is approximately 2.6 per 1000 live birth. The aim of this paper is to analyze the age of diagnosis, hearing aid fitting, and intervention of congenitally hearing impaired children with and without hearing screening after public awareness and government endorsement of newborn hearing screening.
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Evaluation of myocardial function in patients with rheumatoid arthritis using strain imaging by speckle-tracking echocardiography.
Ann. Rheum. Dis.
PUBLISHED: 07-19-2013
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Patients with rheumatoid arthritis (RA) are at increased risk for cardiovascular disease (CVD), although strategies to detect subclinical CVD are poorly characterised. The purpose of this study was to assess myocardial function by speckle-tracking echocardiography strain imaging in patients with RA without known CVD.
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Evaluation of the BD Bactec MGIT 320 system for detection of mycobacteria and drug susceptibility testing of Mycobacterium tuberculosis.
J. Clin. Microbiol.
PUBLISHED: 07-17-2013
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Two different laboratories evaluated growth and detection of mycobacteria and drug susceptibility testing of Mycobacterium tuberculosis by the BD Bactec MGIT 320 using the BD Bactec MGIT 960 (BD Diagnostics, Sparks, MD) as a reference method. Out of 359 processed sputum specimens for detection of mycobacteria, 99.7% were in agreement between the MGIT 320 and MGIT 960. Streptomycin (STR), isoniazid (INH), rifampin (RIF), ethambutol (EMB) (collectively known as SIRE), and pyrazinamide (PZA) drug susceptibility testing was performed on 89 clinical strains, prepared from both liquid and solid inocula. The results of SIRE and PZA were 100% reproducible between the two instruments tested at both laboratories.
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Sex-specific genomic biomarkers for individualized treatment of life-threatening diseases.
Dis. Markers
PUBLISHED: 06-30-2013
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Numerous studies have demonstrated sex differences in drug reactions to the same drug treatment, steering away from the traditional view of one-size-fits-all medicine. A premise of this study is that the sex of a patient influences difference in disease characteristics and risk factors. In this study, we intend to exploit and to obtain better sex-specific biomarkers from gene-expression data. We propose a procedure to isolate a set of important genes as sex-specific genomic biomarkers, which may enable more effective patient treatment. A set of sex-specific genes is obtained by a variable importance ranking using a combination of cross-validation methods. The proposed procedure is applied to three gene-expression datasets.
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Analysis of stress-responsive transcriptome in the intestine of Asian seabass (Lates calcarifer) using RNA-seq.
DNA Res.
PUBLISHED: 06-10-2013
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Identification of differentially expressed genes (DEGs) and regulated pathways in response to stressors using a whole-genome approach is critical to understanding the mechanisms underlying stress responses. We challenged Asian seabass with lipopolysaccharide (LPS), Vibrio harveyi, high salinity and fasting, and sequenced six cDNA libraries of intestine samples using Roche 454 RNA-seq. Over 1 million reads (average size: 516 bp) were obtained. The de novo assembly obtained 83 911 unisequences with an average length of 747 bp. In total, 62.3% of the unisequences were annotated. We observed overall similar expression profiles among different challenges, while a number of DEGs and regulated pathways were identified under specific challenges. More than 1000 DEGs and over 200 regulated pathways for each stressor were identified. Thirty-seven genes were differentially expressed in response to all challenges. Our data suggest that there is a global coordination and fine-tuning of gene regulation during different challenges. In addition, we detected dramatic immune responses in intestines under different stressors. This study is the first step towards the comprehensive understanding of the mechanisms underlying stress responses and supplies significant transcriptome resources for studying biological questions in non-model fish species.
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Fragment-based ligand design of novel potent inhibitors of tankyrases.
J. Med. Chem.
PUBLISHED: 06-04-2013
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Tankyrases constitute potential drug targets for cancer and myelin-degrading diseases. We have applied a structure- and biophysics-driven fragment-based ligand design strategy to discover a novel family of potent inhibitors for human tankyrases. Biophysical screening based on a thermal shift assay identified highly efficient fragments binding in the nicotinamide-binding site, a local hot spot for fragment binding. Evolution of the fragment hit 4-methyl-1,2-dihydroquinolin-2-one (2) along its 7-vector yields dramatic affinity improvements in the first cycle of expansion. A crystal structure of 7-(2-fluorophenyl)-4-methylquinolin-2(1H)-one (11) reveals that the nonplanar compound extends with its fluorine atom into a pocket, which coincides with a region of the active site where structural differences are seen between tankyrases and other poly(ADP-ribose) polymerase (PARP) family members. A further cycle of optimization yielded compounds with affinities and IC50 values in the low nanomolar range and with good solubility, PARP selectivity, and ligand efficiency.
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Mortality in Medicare patients undergoing elective percutaneous coronary intervention with or without antecedent stress testing.
Circ Cardiovasc Qual Outcomes
PUBLISHED: 05-14-2013
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Guidelines advise testing for ischemia, such as with stress testing, before elective percutaneous coronary intervention (PCI). However, pre-PCI stress testing is not always done; the implications of this practice are not known. Our objective was to evaluate whether receipt of stress testing before elective PCI predicts mortality.
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Whole genome scanning and association mapping identified a significant association between growth and a SNP in the IFABP-a gene of the Asian seabass.
BMC Genomics
PUBLISHED: 04-25-2013
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Aquaculture is the quickest growing sector in agriculture. However, QTL for important traits have been only identified in a few aquaculture species. We conducted QTL mapping for growth traits in an Asian seabass F(2) family with 359 individuals using 123 microsatellites and 22 SNPs, and performed association mapping in four populations with 881 individuals.
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Examination of sources of diagnostic error leading to cervical cone biopsies with no evidence of dysplasia.
Am. J. Clin. Pathol.
PUBLISHED: 03-26-2013
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At our institution, 17% of cervical conization specimens are reported as negative for dysplasia or malignancy. To identify sources of error, we reviewed 53 negative conization specimens and their prior and follow-up cytology, biopsy, and endocervical curettage specimens. Examination of deeper-level sections and p16 immunostaining were performed on all conization specimens and selected biopsy specimens. Dysplasia was detected in 26% (14/53) of conization specimens. Twenty-eight percent (15/53) of cones were truly negative, and the presurgical material had been overcalled as high-grade squamous intraepithelial lesions (HSIL). Forty-five percent (24/53) of cones were truly negative and HSIL was confirmed in the presurgical material. Of these, 11% (6/53) showed subsequent evidence of residual dysplasia and 26% (14/53) were negative on further follow-up. Deeper-level sections, p16 immunostains, and consensus review may help identify squamous dysplasia in conization specimens and may prevent the overdiagnosis of HSIL on cervical biopsies.
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An effort to spread decision aids in five California primary care practices yielded low distribution, highlighting hurdles.
Health Aff (Millwood)
PUBLISHED: 02-06-2013
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Despite the proven efficacy of decision aids as interventions for increasing patient engagement and facilitating shared decision making, they are not used routinely in clinical care. Findings from a project designed to achieve such integration, conducted at five primary care practices in 2010-12, document low rates of distribution of decision aids to eligible patients due for colorectal cancer screening (9.3 percent) and experiencing back pain (10.7 percent). There were also no lasting increases in distribution rates in response to training sessions and other promotional activities for physicians and clinic staff. The results of focus groups, ethnographic field notes, and surveys suggest that major structural and cultural changes in health care practice and policy are necessary to achieve the levels of use of decision aids and shared decision making in routine practice envisioned in current policy. Among these changes are ongoing incentives for use, physician training, and a team-based practice model in which all care team members bear formal responsibility for the use of decision aids in routine primary care.
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A microsatellite-based linkage map of salt tolerant tilapia (Oreochromis mossambicus x Oreochromis spp.) and mapping of sex-determining loci.
BMC Genomics
PUBLISHED: 01-22-2013
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Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution.
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Mapping Quantitative Trait Loci for Omega-3 Fatty Acids in Asian Seabass.
Mar. Biotechnol.
PUBLISHED: 01-21-2013
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Omega-3 fatty acids are essential fatty acids for human health. Therefore, increasing both percentage of omega-3 and a better fatty acid profile in fish fillets is one of the breeding goals in aquaculture. However, it is difficult to increase the omega-3 content in fish fillets, as the phenotypic selection of these traits is not easily feasible. To facilitate the genetic improvement of the Asian seabass for optimal fatty acid profiles, a genome-wide scan for quantitative trait loci (QTL) affecting fatty acid level in the flesh of the Asian seabass was performed on an F2 family containing 314 offspring. All family members were genotyped using 123 informative microsatellites and 22 SNPs. High percentages of n-3 polyunsaturated fatty acids (PUFA), especially C22:6 (DHA 16.48?±?3.09 %) and C20:5 (EPA 7.19?±?0.86 %) were detected in the flesh. One significant and 54 suggestive QTL for different fatty acids and a water content trait were detected on the whole genome. QTL for C18:0b was located on linkage groups (LG) 5. QTL for total n-3 PUFA content in flesh were mapped onto LG6 and LG23 with the phenotypic variance explained ranging from 3.8 to 6.3 %. Four QTL for C22:6 were detected on LG6, LG23, and LG24, explaining 3.9 to 4.9 % of the phenotypic variance, respectively. Mapping of QTL for contents of different fatty acids is the first step towards improving the omega-3 content in the fillets of fish by using marker-assisted selection and is important for understanding the biology of fatty acid deposition.
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Implantable cardioverter defibrillators in patients with cardiac amyloidosis.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 01-15-2013
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Cardiac amyloidosis (CA) is associated with increased risk of sudden cardiac arrest. Although ICD therapy improves survival in patients with cardiomyopathy due to other etiologies, the benefit of ICD therapy in patients with CA is unclear in large part due to limited data on the precise mechanism of sudden cardiac arrest and selection of patients with cardiac amyloidosis for ICD therapy.
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Activation of beta 1 but not beta 3 integrin increases cell traction forces.
FEBS Lett.
PUBLISHED: 01-03-2013
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Cell-generated traction forces induce integrin activation, leading to focal adhesion growth and cell spreading. It remains unknown, however, whether integrin activation feeds back to impact the generation of cytoskeletal tension. Here, we used elastomeric micropost arrays to measure cellular traction forces in wildtype and integrin-null cells. We report that activation of ?1 but not ?3 integrin, by either increasing density of immobilized fibronectin or treating with manganese, elicited fibroblast spreading and cytoskeletal tension. Furthermore, this force generation required Rho kinase and myosin activity. These findings suggest that integrin activation and cell traction forces comprise a bi-directional signaling unit of cell adhesion.
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Analysis of the Asian seabass transcriptome based on expressed sequence tags.
DNA Res.
PUBLISHED: 11-15-2011
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Analysis of transcriptomes is of great importance in genomic studies. Asian seabass is an important fish species. A number of genomic tools in it were developed, while large expressed sequence tag (EST) data are lacking. We sequenced ESTs from nine normalized cDNA libraries and obtained 11 431 high-quality ESTs. We retrieved 8524 ESTs from dbEST database and analyzed all 19 975 ESTs using bioinformatics tools. After clustering, we obtained 8837 unique sequences (2838 contigs and 5999 singletons). The average contig length was 574 bp. Annotation of these unique sequences revealed that 48.9% of them showed significant homology to RNA sequences in GenBank. Functional classification of the unique ESTs identified a broad range of genes involved in different functions. We identified 6114 putative single-nucleotide polymorphisms and 634 microsatellites in ESTs. We discovered different temporal and spatial expression patterns of some immune-related genes in the Asian seabass after challenging with a pathogen Vibrio harveyi. The unique EST sequences are being used in developing a cDNA microarray to examine global gene expression and will also facilitate future whole-genome sequence assembly and annotation of Asian seabass and comparative genomics.
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Prediction of hospital acute myocardial infarction and heart failure 30-day mortality rates using publicly reported performance measures.
J Healthc Qual
PUBLISHED: 09-26-2011
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To identify an approach to summarizing publicly reported hospital performance data for acute myocardial infarction (AMI) or heart failure (HF) that best predicts current year hospital mortality rates.
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Integration of BMP, Wnt, and notch signaling pathways in osteoblast differentiation.
J. Cell. Biochem.
PUBLISHED: 07-28-2011
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Bone marrow-derived mesenchymal stem cells (MSCs) are multipotent progenitors that can commit to osteoblast, chondrocyte, adipocyte, and several other lineages. The proper utilization of stem cells for clinical applications requires an integrated understanding of multiple signal inputs that control maintenance of stemness, proliferation, commitment, and differentiation. Various signaling pathways have been implicated in the regulation of MSC differentiation; however, complexities of pathway interactions, as well as seemingly contradictory results in the literature, create an often confusing and disjointed knowledge base. Several recent publications explore the integration of signaling pathways such as BMP, Wnt, Notch, Hedgehog, and Fibroblast Growth Factors in MSC osteoblast differentiation. The transcription factor Cbfa1/Runx2 has been implicated in these pathways as a potential focal point for signaling integration. This review will outline the current understanding of these pathways and indicate where both spatiotemporal effects during differentiation and comparable experimental conditions need to be considered in order to clarify the outcome(s) of differing regulatory levels of these signaling pathways.
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Cytologic findings of a clear cell parathyroid lesion.
Diagn. Cytopathol.
PUBLISHED: 06-20-2011
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On fine-needle aspiration (FNA) biopsy, clear cell parathyroid lesions can be misdiagnosed as thyroid neoplasms, salivary gland neoplasms, paraganglioma, or even metastatic renal cell carcinoma. We report the clinicopathological, cytologic, and histologic findings of a clear cell parathyroid tumor in a 64-year-old HIV-positive patient. A computed tomography (CT) scan with contrast showed a heterogeneous and enhancing mass at the inferolateral aspect of the left thyroid lobe. FNA showed a cellular smear with many single and loosely clustered tumor cells with finely granular and vacuolated light-purple cytoplasm and central nuclei. Occasional microfollicular structures were noted. No colloid was seen. This FNA was misdiagnosed as a follicular neoplasm of the thyroid. Sections of the excised mass showed large polyhedral cells with well-defined cell membranes and clear cytoplasm with a small amount of eosinophilic granular material. These clear cells were positive for pancytokeratin and PTH immunohistochemical stains. These results favored a diagnosis of parathyroid Water Clear Cell Adenoma. This brief report highlights the cytologic findings of clear cell parathyroid lesions and their potential diagnostic pitfalls.
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?2 Integrin-Dependent Suppression of Pancreatic Adenocarcinoma Cell Invasion Involves Ectodomain Regulation of Kallikrein-Related Peptidase-5.
J Oncol
PUBLISHED: 05-25-2011
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Previous reports demonstrate that the ?2-integrin (?2) mediates pancreatic ductal adenocarcinoma (PDAC) cell interactions with collagens. We found that while well-differentiated cells use ?2 exclusively to adhere and migrate on collagenI, poorly differentiated PDAC cells demonstrate reduced reliance on, or complete loss of, ?2. Since well-differentiated PDAC lines exhibit reduced in vitro invasion and ?2-blockade suppressed invasion of well-differentiated lines exclusively, we hypothesized that ?2 may suppress the malignant phenotype in PDAC. Accordingly, ectopic expression of ?2 retarded in vitro invasion and maintenance on collagenI exacerbated this effect. Affymetrix profiling revealed that kallikrein-related peptidase-5 (KLK5) was specifically upregulated by ?2, and reduced ?2 and KLK5 expression was observed in poorly differentiated PDAC cells in situ. Accordingly, well-differentiated PDAC lines express KLK5, and KLK5 blockade increased the invasion of KLK5-positive lines. The ?2-cytoplasmic domain was dispensable for these effects, demonstrating that the ?2-ectodomain and KLK5 coordinately regulate a less invasive phenotype in PDAC.
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Preventing venous thromboembolism following orthopedic surgery in the United States: impact of special populations on clinical outcomes.
Clin. Appl. Thromb. Hemost.
PUBLISHED: 05-17-2011
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Clinical trials of anticoagulants often exclude special populations. We assessed the proportion of special populations in real-world orthopedic surgery and the incidence of venous thromboembolism (VTE)-related outcomes. Data on patients with hip (n = 11 483) or knee replacement (n = 19 390) were extracted from IMS PharMetrics Patient-Centric Database. There was high prevalence of patients aged ?75 years (20.3%), CYP3A4-inhibitor use (21.5%), and chronic warfarin use (9.5%). Venous thromboembolism events were increased with each increasing year of age (hip: odds ratio [OR] 1.02, 95% confidence interval [CI] = 1.01-1.03; knee: OR 1.01, 95%CI = 1.00-1.02) and chronic warfarin use (hip: OR 1.56, 95%CI = 1.13-2.17; knee: OR 1.33, 95%CI = 1.03-1.72); in hip patients with renal insufficiency (OR1.61, 95%CI=1.11-2.36); and in knee patients with atrial fibrillation (OR 1.41, 95%CI = 1.06-1.88). Major bleeding was higher in hip patients with hepatic impairment (OR 21.99, 95%CI = 2.04-236.62), each increasing year of age (OR 1.08, 95%CI = 1.01-1.15), and chronic warfarin use (OR 7.11, 95%CI = 1.16-43.46). Special populations are prevalent in real-world orthopedic surgery, which may impact VTE-related outcomes.
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A first generation microsatellite- and SNP-based linkage map of Jatropha.
PLoS ONE
PUBLISHED: 05-11-2011
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Jatropha curcas is a potential plant species for biodiesel production. However, its seed yield is too low for profitable production of biodiesel. To improve the productivity, genetic improvement through breeding is essential. A linkage map is an important component in molecular breeding. We established a first-generation linkage map using a mapping panel containing two backcross populations with 93 progeny. We mapped 506 markers (216 microsatellites and 290 SNPs from ESTs) onto 11 linkage groups. The total length of the map was 1440.9 cM with an average marker space of 2.8 cM. Blasting of 222 Jatropha ESTs containing polymorphic SSR or SNP markers against EST-databases revealed that 91.0%, 86.5% and 79.2% of Jatropha ESTs were homologous to counterparts in castor bean, poplar and Arabidopsis respectively. Mapping 192 orthologous markers to the assembled whole genome sequence of Arabidopsis thaliana identified 38 syntenic blocks and revealed that small linkage blocks were well conserved, but often shuffled. The first generation linkage map and the data of comparative mapping could lay a solid foundation for QTL mapping of agronomic traits, marker-assisted breeding and cloning genes responsible for phenotypic variation.
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Selection of music for inducing relaxation and alleviating pain: literature review.
Holist Nurs Pract
PUBLISHED: 04-22-2011
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The use of music as an intervention involves choices. What kind of music should be used? Who should choose the music? Thirty-one articles were reviewed. To maximize effects, the primary music selection should be based on research and then a variety of selections be presented to individuals for choice on the basis of personal preferences.
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Reliability of Her2/neu, estrogen receptor, and progesterone receptor testing by immunohistochemistry on cell block of FNA and serous effusions from patients with primary and metastatic breast carcinoma.
Diagn. Cytopathol.
PUBLISHED: 04-14-2011
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The prognostic and predictive value of Her2/neu and the hormone receptors in patient with primary or metastatic breast cancer is essential for a favorable outcome of treatment. We have been experiencing increasing requests to test cytologic specimens for these markers in patients with metastatic breast carcinoma. A recent study threw some doubts on the validity of such testing using cell blocks. In this study we compared our immunohistochemical Her2/neu, ER and PR testing performed on 42 formalin-fixed, paraffin-embedded cell blocks from 27 fine needle aspirations (FNA) and 15 serous effusions of 42 patients with metastatic (n = 38) and primary (n = 4) breast carcinoma to the test results obtained on tissue sections. In seven cases the Her2/neu immunohistochemistry (IHC) results on cell blocks were also compared with Her2/neu fluorescence in situ hybridization (FISH) on tissue or cell block. The study revealed 100% correlation for positive and negative Her2/neu results. For ER testing the results showed 85.7% sensitivity, 100% specificity, 100% positive predictive value (PPV), and 85.7% negative predictive value (NPV). For PR testing the results showed 80% sensitivity, 100% specificity, 100% PPV, and 88.8% NPV respectively. In conclusion, IHC for Her2/neu, ER and PR performed on formalin-fixed, paraffin-embedded cell blocks prepared from fresh FNA and serous fluid is reliable in predicting the expression of these markers when correlated with IHC and FISH performed on the corresponding tumor tissue.
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Cell of origin in AML: susceptibility to MN1-induced transformation is regulated by the MEIS1/AbdB-like HOX protein complex.
Cancer Cell
PUBLISHED: 04-03-2011
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Pathways defining susceptibility of normal cells to oncogenic transformation may be valuable therapeutic targets. We characterized the cell of origin and its critical pathways in MN1-induced leukemias. Common myeloid (CMP) but not granulocyte-macrophage progenitors (GMP) could be transformed by MN1. Complementation studies of CMP-signature genes in GMPs demonstrated that MN1-leukemogenicity required the MEIS1/AbdB-like HOX-protein complex. ChIP-sequencing identified common target genes of MN1 and MEIS1 and demonstrated identical binding sites for a large proportion of their chromatin targets. Transcriptional repression of MEIS1 targets in established MN1 leukemias demonstrated antileukemic activity. As MN1 relies on but cannot activate expression of MEIS1/AbdB-like HOX proteins, transcriptional activity of these genes determines cellular susceptibility to MN1-induced transformation and may represent a promising therapeutic target.
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A high-resolution linkage map for comparative genome analysis and QTL fine mapping in Asian seabass, Lates calcarifer.
BMC Genomics
PUBLISHED: 04-02-2011
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High density linkage maps are essential for comparative analysis of synteny, fine mapping of quantitative trait loci (QTL), searching for candidate genes and facilitating genome sequence assembly. However, in most foodfish species, marker density is still low. We previously reported a first generation linkage map with 240 DNA markers and its application to preliminarily map QTL for growth traits in Asian seabass (Lates calcarifer). Here, we report a high-resolution linkage map with 790 microsatellites and SNPs, comparative analysis of synteny, fine-mapping of QTL and the identification of potential candidate genes for growth traits.
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Giant room temperature electric-field-assisted magnetoresistance in La0.7Sr0.3MnO3/n-Si nanotip heterojunctions.
Nanotechnology
PUBLISHED: 02-14-2011
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An on-chip approach for fabricating ferromagnetic/semiconductor-nanotip heterojunctions is demonstrated. The high-density array of Si nanotips (SiNTs) is employed as a template for depositing La(0.7)Sr(0.3)MnO(3) (LSMO) rods with a pulsed-laser deposition method. Compared with the planar LSMO/Si thin film, the heterojunction shows a large enhancement of room temperature magnetoresistance (MR) ratio up to 20% under 0.5 T and a bias current of 20 µA. The MR ratio is found to be tunable, which increases with increasing external bias and the aspect ratios of the nanotips. Electric-field-induced metallization, in conjunction with nanotip geometry, is proposed to be the origin for the giant MR ratio.
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Single-center experience with implantable cardioverter-defibrillators in adults with complex congenital heart disease.
Am. J. Cardiol.
PUBLISHED: 02-04-2011
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Adults with congenital heart disease are at risk of lethal ventricular arrhythmias and are candidates for implantable cardiac defibrillator (ICD) therapy, yet implant risks, long-term outcomes, and rates of appropriate and inappropriate ICD therapies are not well characterized. We reviewed clinical, implantation, and follow-up data on all transvenous ICDs in adults with congenital heart disease at the Mayo Clinic from 1991 through 2008. Seventy-three adults with congenital heart disease received 85 ICDs. Implantation diagnoses included tetralogy of Fallot (44%) and congenitally corrected transposition of the great arteries (17%). Implantation indication was occurrence of sustained ventricular arrhythmias (secondary prevention) in 36% and prophylactic (primary prevention) in the remainder. There were no major implant-related complications. During follow-up (2.2 ± 2.8 years, range 0 to 15) 11 patients died and 4 patients received heart or heart/lung transplants. An appropriate shock for a ventricular arrhythmia was observed in 19% of patients and an inappropriate shock was observed in 15% of patients. Likelihood of an appropriate shock was associated with increased subpulmonic ventricular pressure. In conclusion, implantation of transvenous ICDs in adults with congenital heart disease is associated with a low risk of implant complications. In this high-risk adult population the rate of inappropriate ICD shocks is low, whereas the likelihood of appropriate therapy for potentially lethal ventricular arrhythmias is high. These data suggest overall benefit of ICD therapy in adults with congenital heart disease.
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C/EBP? mediates growth hormone-regulated expression of multiple target genes.
Mol. Endocrinol.
PUBLISHED: 02-03-2011
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Regulation of c-Fos transcription by GH is mediated by CCAAT/enhancer binding protein ? (C/EBP?). This study examines the role of C/EBP? in mediating GH activation of other early response genes, including Cyr61, Btg2, Socs3, Zfp36, and Socs1. C/EBP? depletion using short hairpin RNA impaired responsiveness of these genes to GH, as seen for c-Fos. Rescue with wild-type C/EBP? led to GH-dependent recruitment of the coactivator p300 to the c-Fos promoter. In contrast, rescue with C/EBP? mutated at the ERK phosphorylation site at T188 failed to induce GH-dependent recruitment of p300, indicating that ERK-mediated phosphorylation of C/EBP? at T188 is required for GH-induced recruitment of p300 to c-Fos. GH also induced the occupancy of phosphorylated C/EBP? and p300 on Cyr61, Btg2, and Socs3 at predicted C/EBP-cAMP response element-binding protein motifs in their promoters. Consistent with a role for ERKs in GH-induced expression of these genes, treatment with U0126 to block ERK phosphorylation inhibited their GH-induced expression. In contrast, GH-dependent expression of Zfp36 and Socs1 was not inhibited by U0126. Thus, induction of multiple early response genes by GH in 3T3-F442A cells is mediated by C/EBP?. A subset of these genes is regulated similarly to c-Fos, through a mechanism involving GH-stimulated ERK 1/2 activation, phosphorylation of C/EBP?, and recruitment of p300. Overall, these studies suggest that C/EBP?, like the signal transducer and activator of transcription proteins, regulates multiple genes in response to GH.
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Surgical management of endobronchial inflammatory myofibroblastic tumors.
Ann. Thorac. Surg.
PUBLISHED: 01-25-2011
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Endobronchial myofibroblastic tumors are neoplasms composed of clonal populations of smooth muscle cells and a variable lymphocytic inflammatory component. They represent a challenge with respect to diagnosis, classification, and surgical resection due to their infrequent occurrence.
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Effect of identification and intervention age on language development for Mandarin-speaking deaf children with high family involvement.
Int. J. Pediatr. Otorhinolaryngol.
PUBLISHED: 01-14-2011
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The purpose of this study is to assess the language ability between early-intervention and later-intervention Mandarin-speaking deaf children, who have normal cognition and high family involvement.
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Interaction between small GTPase Rab7 and PI3KC3 links autophagy and endocytosis: A new Rab7 effector protein sheds light on membrane trafficking pathways.
Small GTPases
PUBLISHED: 01-06-2011
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Endocytosis and autophagy are both membrane trafficking pathways vital for cell survival. Endocytosis, the primary means by which cells internalize material such as cell-surface receptors and their protein ligands, is essential for proper cell growth and communication. Autophagy is a catabolic process that degrades cargo ranging from organelles to protein aggregates to bacteria, and it is important for maintaining cellular homeostasis. Defects in both endosome and autophagosome maturation lead to an array of human diseases, including cancer; however, the molecular mechanisms underlying endosome and autophagosome maturation are not well characterized. In the case of endocytosis, small GTPases, key players in membrane organization, are required for endosome maturation. Specifically, activation of the small GTPase Rab7 is required for the initiation of the early-to-late endosome transition, although how this is regulated is largely unknown. Now recent findings from our laboratory show that Rubicon, a component of the PI3KC3 complex, inhibits endosome maturation by preventing activation of Rab7. Not only do our results clarify the molecular link between PI3KC3 and Rab7 function in endosome maturation, they lead us to propose new models for PI3KC3 involvement in membrane trafficking, particularly at the convergence between the endosome and autophagosome pathways.
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Renal function and mortality following cardiac resynchronization therapy.
Eur. Heart J.
PUBLISHED: 11-10-2010
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Cardiac resynchronization therapy (CRT) improves outcomes in heart failure, yet selection of patients likely to have survival benefit is problematic. Chronic kidney disease (CKD) is an important determinant of mortality in patients with congestive heart failure therefore we sought to determine the impact of CKD on mortality benefit after CRT.
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Determinants of multidrug-resistant tuberculosis clusters, California, USA, 2004-2007.
Emerging Infect. Dis.
PUBLISHED: 08-26-2010
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Laboratory and epidemiologic evidence suggests that pathogen-specific factors may affect multidrug-resistant (MDR) tuberculosis (TB) transmission and pathogenesis. To identify demographic and clinical characteristics of MDR TB case clustering and to estimate the effect of specific isoniazid resistance-conferring mutations and strain lineage on genotypic clustering, we conducted a population-based cohort study of all MDR TB cases reported in California from January 1, 2004, through December 31, 2007. Of 8,899 incident culture-positive cases for which drug susceptibility information was available, 141 (2%) were MDR. Of 123 (87%) strains with genotype data, 25 (20%) were aggregated in 8 clusters; 113 (92%) of all MDR TB cases and 21 (84%) of clustered MDR TB cases occurred among foreign-born patients. In multivariate analysis, the katG S315T mutation (odds ratio 11.2, 95% confidence interval 2.2-Yen; p = 0.004), but not strain lineage, was independently associated with case clustering.
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Rapid drug susceptibility testing with a molecular beacon assay is associated with earlier diagnosis and treatment of multidrug-resistant tuberculosis in California.
J. Clin. Microbiol.
PUBLISHED: 08-11-2010
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To assess the clinical impact of a molecular beacon (MB) assay that detects multidrug-resistant tuberculosis (MDR TB), we retrospectively reviewed records of 127 MDR TB patients with and without MB testing between 2004 and 2007. Use of the MB assay reduced the time to detection and treatment of MDR TB.
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Dyssynchrony indices to predict response to cardiac resynchronization therapy: a comprehensive prospective single-center study.
Circ Heart Fail
PUBLISHED: 07-20-2010
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Whether mechanical dyssynchrony indices predict reverse remodeling (RR) or clinical response to cardiac resynchronization therapy (CRT) remains controversial. This prospective study evaluated whether echocardiographic dyssynchrony indices predict RR or clinical response after CRT.
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A tryptophan-rich peptide acts as a transcription activation domain.
BMC Mol. Biol.
PUBLISHED: 07-17-2010
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Eukaryotic transcription activators normally consist of a sequence-specific DNA-binding domain (DBD) and a transcription activation domain (AD). While many sequence patterns and motifs have been defined for DBDs, ADs do not share easily recognizable motifs or structures.
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Impact of changes in clinical practice guidelines on assessment of quality of care.
Med Care
PUBLISHED: 07-09-2010
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Measures for pay-for-performance and public reporting programs may be based on clinical practice guidelines. The impact of guideline changes over time-and whether evolving clinical evidence can render measures based on prior guidelines misleading-is not known.
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A first generation BAC-based physical map of the Asian seabass (Lates calcarifer).
PLoS ONE
PUBLISHED: 04-20-2010
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The Asian seabass (Lates calcarifer) is an important marine foodfish species in Southeast Asia and Australia. Genetic improvement of this species has been achieved to some extent through selective breeding programs since 1990s. Several genomic tools such as DNA markers, a linkage map, cDNA and BAC libraries have been developed to assist selective breeding. A physical map is still lacking, although it is essential for positional cloning of genes located in quantitative trait loci (QTL) and assembly of whole genome sequences.
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Inside-out regulation of L1 conformation, integrin binding, proteolysis, and concomitant cell migration.
Mol. Biol. Cell
PUBLISHED: 03-24-2010
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Previous reports on the expression of the cell adhesion molecule L1 in pancreatic ductal adenocarcinoma (PDAC) cells range from absent to high. Our data demonstrate that L1 is expressed in poorly differentiated PDAC cells in situ and that threonine-1172 (T1172) in the L1 cytoplasmic domain exhibits steady-state saturated phosphorylation in PDAC cells in vitro and in situ. In vitro studies support roles for casein kinase II and PKC in this modification, consistent with our prior studies using recombinant proteins. Importantly, T1172 phosphorylation drives, or is associated with, a change in the extracellular structure of L1, consistent with a potential role in regulating the shift between the closed conformation and the open, multimerized conformation of L1. We further demonstrate that these distinct conformations exhibit differential binding to integrins alphavbeta3 and alphavbeta5 and that T1172 regulates cell migration in a matrix-specific manner and is required for a disintegrin and metalloproteinase-mediated shedding of the L1 ectodomain that has been shown to regulate cell migration. These data define a specific role for T1172 of L1 in regulating aspects of pancreatic adenocarcinoma cell phenotype and suggest the need for further studies to elucidate the specific ramifications of L1 expression and T1172 phosphorylation in the pathobiology of pancreatic cancer.
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The use of immunohistochemistry to distinguish reactive mesothelial cells from malignant mesothelioma in cytologic effusions.
Cancer Cytopathol
PUBLISHED: 03-09-2010
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The distinction of benign from malignant mesothelial proliferations in cytologic specimens can be problematic. In this study, the authors investigated the utility of immunohistochemical (IHC) markers in making this distinction.
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Multipotent mesenchymal progenitor cells are present in endarterectomized tissues from patients with chronic thromboembolic pulmonary hypertension.
Am. J. Physiol., Cell Physiol.
PUBLISHED: 02-24-2010
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Factors contributing to the development of a fibrotic vascular scar and pulmonary vascular remodeling leading to chronic thromboembolic pulmonary hypertension (CTEPH) are still unknown. This study investigates the potential contribution of multipotent progenitor cells and myofibroblasts to the development and progression of CTEPH. Histological examination of endarterectomized tissues from patients with CTEPH identified significant neointimal formation. Morphological heterogeneity was observed in cells isolated from these tissues, including a network-like growth pattern and the formation of colony-forming unit-fibroblast-like colonies (CFU-F). Cells typically coexpressed intermediate filaments vimentin and smooth muscle alpha-actin. Cells were characterized by immunofluorescence and quantitated by fluorescent-activated cell sorting (FACS) for the presence of cell surface markers typical of mesenchymal progenitor cells; cells were >99% CD44(+) CD73(+), CD90(+), CD166(+); >80% CD29(+); 45-99% CD105(+); CD34(-) and CD45(-). Cells were capable of adipogenic and osteogenic differentiation, determined by Oil Red O and Alizarin Red staining, respectively. Additionally, a population of Stro-1(+) cells, a marker of bone marrow-derived stromal cells (4.2%), was sorted by FACS and also capable of adipogenic and osteogenic differentiation. In conclusion, this study is the first to identify a myofibroblast cell phenotype to be predominant within endarterectomized tissues, contributing extensively to the vascular lesion/clot. This cell may arise from transdifferentiation of adventitial fibroblasts or differentiation of mesenchymal progenitor cells. The unique microenvironment created by the stabilized clot is likely a factor in stimulating such cellular changes. These findings will be critical in establishing future studies in the development of novel and much needed therapeutic approaches for pulmonary hypertension.
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Interactions between sleep disordered breathing and atrial fibrillation in patients with hypertrophic cardiomyopathy.
Am. J. Cardiol.
PUBLISHED: 01-13-2010
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The aim of this study was to investigate whether patients with hypertrophic cardiomyopathy (HC) and sleep disordered breathing (SDB) have a higher prevalence of atrial fibrillation (AF) compared to patients with HC without SDB. HC is associated with a high prevalence of AF that contributes to increased morbidity and mortality. SDB is strongly associated with a higher incidence, prevalence, and recurrence of AF in patients without HC. Whether this association also applies to patients with HC is not known. Overnight oximetry was prospectively performed on 91 consecutive patients with echocardiographically confirmed HC. The presence or absence of AF in this population was correlated with the oximetric findings. SDB was associated with a higher prevalence of AF (40% vs 11%, p = 0.005). In addition, SDB was accompanied by significantly increased left atrial volume index (58 +/- 19 vs 42 +/- 13 ml/m(2), p = 0.0002). Increasing severity of SDB was correlated with higher AF prevalence and with increase in left atrial volume index. These associations remained significant even after accounting for potential confounders in a multivariate analysis. In conclusion, these findings suggest that the presence and severity of SDB may influence left atrial volume index and the prevalence of AF in patients with HC. SDB may therefore be an important and potentially modifiable cause of morbidity and mortality in this population.
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Patient decision aids for prostate cancer treatment: a systematic review of the literature.
CA Cancer J Clin
PUBLISHED: 10-19-2009
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Treatment decision-making can be difficult and complex for patients with low-risk prostate cancer. To the authors knowledge, there is no consensus regarding an optimal treatment strategy and the choice of therapy involves tradeoffs between differing harms and benefits that are sensitive to patient values. In such situations, patients are often asked to participate actively in the decision-making process, and high-quality decisions require a well-informed patient whose values and preferences have been taken into consideration. Prior studies have indicated that patients have poor knowledge and unrealistic expectations regarding treatment, and physician judgments concerning patient preferences are often inaccurate. Decision aids (DAs) have been developed to help inform patients with low-risk prostate cancer about treatment options and assist in the decision-making process; however, little is currently known regarding the effects of such programs in this population. Thirteen studies of DAs for patients with prostate cancer were reviewed and it was found that the use of DAs can improve knowledge, encourage more active patient involvement in decision-making, and decrease levels of anxiety and distress. The effect of DAs on treatment choice was less clear, although fewer patients chose surgery compared with historical controls, particularly in Europe. Further studies are needed to determine how best to implement DAs into practice, and whether they improve the consistency between patient preferences and treatment choice.
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Use of stress testing prior to percutaneous coronary intervention in patients with stable coronary artery disease.
Expert Rev Cardiovasc Ther
PUBLISHED: 09-22-2009
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The majority of percutaneous coronary interventions (PCIs) are carried out in nonurgent situations, primarily in patients with stable coronary artery disease. Recent trials have concluded that for patients with stable coronary artery disease, treatment with optimal medical therapy versus optimal medical therapy plus PCI yields equivalent outcomes in terms of morbidity and future risk of myocardial infarction. Since PCI is a procedure with risk, it is important to identify patients for whom the benefit of the procedure outweighs the harms. PCI may be beneficial in certain subgroups, such as patients with moderate-to-severe ischemia on noninvasive testing. Although current guidelines require documentation of ischemia prior to elective PCI and this strategy is cost effective, pre-PCI stress testing appears to be underutilized, potentially leading to PCI being performed in patients who may not derive benefit from the procedure.
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Multicenter evaluation of Bactec MGIT 960 system for second-line drug susceptibility testing of Mycobacterium tuberculosis complex.
J. Clin. Microbiol.
PUBLISHED: 09-09-2009
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The Bactec MGIT 960 system for testing susceptibility to second-line drugs was evaluated with 117 clinical strains in a multicenter study. The four drugs studied were levofloxacin, amikacin, capreomycin, and ethionamide. The critical concentration established for levofloxacin and amikacin was 1.5 microg/ml, that established for capreomycin was 3.0 microg/ml, and that established for ethionamide was 5.0 microg/ml. The overall level of agreement between the agar proportion method and the MGIT 960 system was 96.4%, and the levels of agreement for the individuals drugs were 99.1% for levofloxacin, 100% for amikacin, 97.4% for capreomycin, and 88.9% for ethionamide. The rate of reproducibility of the drug susceptibility testing results between the participating laboratories was 99.5%.
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Long-term stability of endocardial left ventricular pacing leads placed via the coronary sinus.
Pacing Clin Electrophysiol
PUBLISHED: 09-02-2009
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Left ventricular endocardial pacing leads placed via the coronary sinus (CS) are increasingly implanted to achieve cardiac resynchronization therapy (CRT); however, the long-term stability of these leads is unknown. We sought to determine the implant success and long-term stability of CS leads in our single center experience.
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Modeling the functional heterogeneity of leukemia stem cells: role of STAT5 in leukemia stem cell self-renewal.
Blood
PUBLISHED: 08-10-2009
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Although the cancer stem cell (CSC) concept implies that CSCs are rare, recent reports suggest that CSCs may be frequent in some cancers. We hypothesized that the proportion of leukemia stem cells would vary as a function of the number of dysregulated pathways. Constitutive expression of MN1 served as a 1-oncogene model, and coexpression of MN1 and a HOX gene served as a 2-oncogene model. Leukemia-initiating cell (LIC) number and in vitro expansion potential of LICs were functionally assessed by limiting dilution analyses. LIC expansion potential was 132-fold increased in the 2- compared with the 1-oncogene model, although phenotypically, both leukemias were similar. The 2-oncogene model was characterized by granulocyte-macrophage colony-stimulating factor (GM-CSF) hypersensitivity and activated STAT/ERK signaling. GM-CSF hypersensitivity of the 2-oncogene model (MN1/HOXA9) was lost in Stat5b(-/-) cells, and the LIC expansion potential was reduced by 86- and 28-fold in Stat5b(-/-) and Stat1(-/-) cells, respectively. Interestingly, in 201 acute myeloid leukemia (AML) patients, coexpression of MN1 and HOXA9 was restricted to patients with the poorest prognosis and was associated with highly active STAT signaling. Our data demonstrate the functional heterogeneity of LICs and show that STAT signaling is critical for leukemia stem cell self-renewal in MN1- and HOXA9-expressing leukemias.
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Lipoprotein processing is essential for resistance of Mycobacterium tuberculosis to malachite green.
Antimicrob. Agents Chemother.
PUBLISHED: 07-13-2009
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Malachite green, a synthetic antimicrobial dye, has been used for over 50 years in mycobacterial culture medium to inhibit the growth of contaminants. The molecular basis of mycobacterial resistance to malachite green is unknown, although the presence of malachite green-reducing enzymes in the cell envelope has been suggested. The objective of this study was to investigate the role of lipoproteins in resistance of Mycobacterium tuberculosis to malachite green. The replication of an M. tuberculosis lipoprotein signal peptidase II (lspA) mutant (DeltalspA::lspAmut) on Middlebrook agar with and without 1 mg/liter malachite green was investigated. The lspA mutant was also compared with wild-type M. tuberculosis in the decolorization rate of malachite green and sensitivity to sodium dodecyl sulfate (SDS) detergent and first-line antituberculosis drugs. The lspA mutant has a 10(4)-fold reduction in CFU-forming efficiency on Middlebrook agar with malachite green. Malachite green is decolorized faster in the presence of the lspA mutant than wild-type bacteria. The lspA mutant is hypersensitive to SDS detergent and shows increased sensitivity to first-line antituberculosis drugs. In summary, lipoprotein processing by LspA is essential for resistance of M. tuberculosis to malachite green. A cell wall permeability defect is likely responsible for the hypersensitivity of lspA mutant to malachite green.
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Discovery of a potent and orally active hedgehog pathway antagonist (IPI-926).
J. Med. Chem.
PUBLISHED: 06-16-2009
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Recent evidence suggests that blocking aberrant hedgehog pathway signaling may be a promising therapeutic strategy for the treatment of several types of cancer. Cyclopamine, a plant Veratrum alkaloid, is a natural product antagonist of the hedgehog pathway. In a previous report, a seven-membered D-ring semisynthetic analogue of cyclopamine, IPI-269609 (2), was shown to have greater acid stability and better aqueous solubility compared to cyclopamine. Further modifications of the A-ring system generated three series of analogues with improved potency and/or solubility. Lead compounds from each series were characterized in vitro and evaluated in vivo for biological activity and pharmacokinetic properties. These studies led to the discovery of IPI-926 (compound 28), a novel semisynthetic cyclopamine analogue with substantially improved pharmaceutical properties and potency and a favorable pharmacokinetic profile relative to cyclopamine and compound 2. As a result, complete tumor regression was observed in a Hh-dependent medulloblastoma allograft model after daily oral administration of 40 mg/kg of compound 28.
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An FGF-responsive astrocyte precursor isolated from the neonatal forebrain.
Glia
PUBLISHED: 05-14-2009
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Gliogenesis in the mammalian CNS continues after birth, with astrocytes being generated well into the first two postnatal weeks. In this study, we have isolated an A2B5(+) astrocyte precursor (APC) from the postnatal rat forebrain, which is capable of differentiating into mature astrocytes in serum-free medium without further trophic support. Exposure to basic fibroblast growth factor (bFGF) selectively induces the APCs to proliferate, forming clusters of vimentin(+) cells, which, within 2 weeks, differentiate into GFAP(+) astrocytes. While bFGF functions as a potent mitogen, neither is it necessary to induce or maintain astrocyte differentiation, nor is it capable of maintaining the precursors in an immature, proliferative state. APCs exit the cell cycle and differentiate, even in the continued presence of fibroblast growth factor alone or in combination with other mitogenic factors such as platelet-derived growth factor. Under the culture conditions used, it was not possible to cause the astrocytes to re-enter cell cycle. After transplantation into the neonatal forebrain, APCs differentiated exclusively into astrocytes, regardless of brain region. Initially distributed widely within the forebrain, the precursors are most greatly concentrated within the subventricular zone (SVZ) and subcortical white matter, where they are maintained throughout postnatal development. APCs can be isolated from the SVZ and white matter of animals as late as 4 weeks after birth.
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