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Find video protocols related to scientific articles indexed in Pubmed.
Dipstick proteinuria is an independent predictor of high on treatment platelet reactivity in patients on clopidogrel, but not aspirin, admitted for major adverse cardiovascular events.
Platelets
PUBLISHED: 10-30-2014
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Abstract The effectiveness of aspirin and clopidogrel in patients with chronic kidney disease (CKD) suffering from acute cardiovascular events is unclear. High on treatment platelet reactivity (HTPR) has been associated with worse outcomes. Here, we assessed the association of dipstick proteinuria (DP) and renal function on HTPR and clinical outcomes. Retrospective cohort analysis of 261 consecutive, non-dialysis patients admitted for Major Adverse Cardiovascular Events (MACE) that had VerifyNow P2Y12 and VerifyNow Aspirin assays performed. HTPR was defined as P2Y12 reactivity unit (PRU)?>?208 for clopidogrel and aspirin reaction units (ARU)?>?550 for aspirin. Renal function was classified based on the estimated glomerular filtration rate (eGFR), and dipstick proteinuria was defined as ?30?mg/dl of albumin detected on a spot analysis. All cause mortality, readmissions, and cardiac catheterizations were reviewed over 520 days. In patients on clopidogrel (n?=?106), DP was associated with HTPR, independent of eGFR, diabetes mellitus, smoking or use of proton pump inhibitor (AOR?=?4.76, p?=?0.03). In patients with acute coronary syndromes, HTPR was associated with more cardiac catheterizations (p?=?0.009) and readmissions (p?=?0.032), but no differences in in-stent thrombosis or re-stenosis were noted in this cohort. In patients on aspirin (n?=?155), no associations were seen between DP and HTPR. However, all cause mortality was significantly higher with HTPR in this group (p?=?0.038). In this cohort, DP is an independent predictor of HTPR in patients on clopidogrel, but not aspirin, admitted to the hospital for MACE.
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[A pilot study of the professional autonomy, job satisfaction, and related factors of nurses at a regional hospital].
Hu Li Za Zhi
PUBLISHED: 10-02-2014
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Professional autonomy often causes confusion in nursing staffs that limit their ability to perform to the best of their professional capabilities. Moreover, heavy and busy workloads reduce the energy available for work resulting in lower working efficiency and lower job satisfaction.
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Effect of body-scaled information on reaching in children with hemiplegic cerebral palsy: a pilot study.
Pediatr Phys Ther
PUBLISHED: 09-17-2014
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This study examined body-scaled information that specifies the reach patterns of children with hemiplegic cerebral palsy and children with typical development.
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Modified toy cars for mobility and socialization: case report of a child with cerebral palsy.
Pediatr Phys Ther
PUBLISHED: 09-17-2014
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Children with cerebral palsy have limited opportunities to explore their physical and social environment. The purpose of this study was to determine the feasibility of using a "ride-on toy car" as a readily available, low-cost, fun, and functional option for children with special needs.
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Crestal bone resorption in augmented bone using mineralized freeze-dried bone allograft or pristine bone during submerged implant healing: a prospective study in humans.
Clin Oral Implants Res
PUBLISHED: 09-16-2014
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There is limited evidence on the crestal bone level changes around implants placed in bone augmented by guided bone regeneration (GBR) during submerged healing. The purpose of this study was to prospectively compare radiographic crestal bone changes around implants placed in augmented bone with changes around implants placed in pristine bone.
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Duration of slip-resistant shoe usage and the rate of slipping in limited-service restaurants: results from a prospective and crossover study.
Ergonomics
PUBLISHED: 09-10-2014
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Several studies have indicated that slip-resistant shoes may have a positive effect on reducing the risk of slips and falls, a leading cause of injury at work. Few studies, however, have examined how duration of shoe usage affects their slip-resistance properties. This study examined the association between the duration of slip-resistant shoes usage and the self-reported rate of slipping in limited-service restaurant workers. A total of 475 workers from 36 limited-service restaurants in the USA were recruited to participate in a 12-week prospective study of workplace slipping. Of the 475 participants, 83 reported changing to a new pair of shoes at least once during the 12-week follow-up. The results show that slip-resistant shoes worn for less than six months were moderately more effective than those worn for more than six months. Changing to a new pair of shoes among those wearing slip-resistant shoes at baseline was associated with a 55% reduction in the rate of slipping (RR = 0.45, 95% CI = 0.23-0.89). Further research is needed to develop criteria for the replacement of slip-resistant shoes. Practitioner Summary: The duration of usage impacts the slip-resistance properties of slip-resistant shoes. Slip-resistant shoes worn for less than six months were moderately more effective in reducing slips than slip-resistant shoes worn for more than six months. Shoe use policies should not only encourage or require their use but also include guidance on replacing slip-resistant shoes at regular intervals.
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Characterization and human osteoblastic proliferation- and differentiation-stimulatory effects of phosphatidylcholine liposomes-encapsulated propranolol hydrochloride.
Biomed Mater Eng
PUBLISHED: 09-10-2014
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DMPC and DSPC liposomes were prepared via thin film hydration method followed by sonication. Propranolol solution was incorporated into liposomes at hydration stage. TEM images showed the sizes of DSPC and DMPC were around 88 and 137 nm, respectively. The highest encapsulation ratio of propranolol was approximately 70% using DSPC/CHO/OCT liposomes, which release the drug over 60% in 24 h and reached 100% in 48 h. Both propranolol (10??-10?? M) and DSCP liposomes-encapsulated propranolol showed over 1.5-fold increases in the proliferation of human osteoblastic cells hFOB1.19 while differentiation of the cells was approximately doubled by plain and liposomal propranolol, indicating that the stimulatory effects of liposomal propranolol are similar with those of propranolol on human osteoblastic hFOB1.19 cells. The phosphatidylcholine liposomes-encapsulated propranolol prepared in this study potentially possesses anabolic effects in vivo and is also a promising anti-osteoporotic agent in future.
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Modified ride-on car for mobility and socialization: single-case study of an infant with Down syndrome.
Pediatr Phys Ther
PUBLISHED: 09-06-2014
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Before the onset of walking, children with Down syndrome experience limited mobility yet are never considered candidates for traditional powered mobility devices. The purpose of this single-case study is to quantify the feasibility and family perceptions of including modified ride-on car use as an option for increasing daily mobility, socialization, and fun for a child with Down syndrome.
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Structural perspectives of an engineered ?-1,4-xylanase with enhanced thermostability.
J. Biotechnol.
PUBLISHED: 09-03-2014
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The glycoside hydrolase 10 (GH10) xylanase from Streptomyces sp. 9 (XynAS9) can operate in a broad range of pH and temperature, and thus is a potential candidate for commercial applications. Recently, we engineered XynAS9 via mutating several residues in accordance with the consensus sequences of GH10 thermophilic xylanases in an attempt to improve the enzyme thermostability and thermotolerance. The most promising effects were observed in the double mutant V81P/G82E. In order to investigate the molecular mechanism of the improved thermal profile of XynAS9, complex crystal structures of the wild type (WT) and mutant (MT) enzyme were solved at 1.88-2.05? resolution. The structures reveal a classical GH10 (?/?)8 TIM-barrel fold. In MT XynAS9, E82 forms several interactions to its neighboring residues, which might aid in stabilizing the local structure. Furthermore, the MT structure showed lower B factors for individual residues compared to the WT structure, reflecting the increased MT protein rigidity. Analyses of the XynAS9 structures also delineate the detailed enzyme-substrate interaction network. More importantly, possible explanations for the enhanced thermal profiles of MT XynAS9 are proposed, which may be a useful strategy for enzyme engineering in the future.
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Roles of tryptophan residue and disulfide bond in the variable lid region of oxidized polyvinyl alcohol hydrolase.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-27-2014
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Oxidized polyvinyl alcohol hydrolase (OPH) catalyzes the cleavage of C-C bond in ?-diketone. It belongs to the ?/?-hydrolase family and contains a unique lid region that covers the active site. The lid is the most variable region when pOPH from Pseudomonas sp. VM15C and sOPH from Sphingopyxis sp. 113P3 are compared. The wild-type enzymes and the pOPH mutants W255A, W255Y and W255F were analyzed for lipase activity by using p-nitrophenyl (pNP) esters as the substrates. The wild-type enzymes showed increased Km and decreased kcat/Km with the acyl chain length, and the mutants showed reduced kcat/Km for pNP acetate, indicating the importance of Trp255 in sequestering the active site from solvent. The significantly lower activity for pNP butyrate can be a result of product inhibition, as suggested by the complex crystal structures, in which butyric acid, DMSO or PEG occupied the same substrate-binding cleft. The mutant activity was retained with pNP caprylate and pNP laurate as the substrates, reflecting the amphipathic nature of the cleft. Moreover, the disulfide bond formation of Cys257/267 is important for the activity of pOPH, but it is not essential for sOPH, which has a shorter lid structure.
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Cognition-Modulated Frontal Activity in Prediction and Augmentation of Antidepressant Efficacy: A Randomized Controlled Pilot Study.
Cereb. Cortex
PUBLISHED: 08-27-2014
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Higher rostral anterior cingulate cortex (rACC) activity correlated with frontal theta power (frontal?) is associated with better antidepressant responses. The antidepressant efficacy of repetitive transcranial magnetic stimulation (rTMS) varied widely; however, the effects of TMS might be modulated by manipulating the pretreatment neural states. Therefore, we conducted a pilot study to investigate whether manipulated frontal? before rTMS treatment could predict and augment antidepressant responses. A computerized rACC-engaging cognitive task (RECT) was exploited continuously for 10 min to patients with major depressive disorder. In total, 36 patients were randomized to 3 groups (Group-A: RECT[active] + rTMS[active]; Group-B: RECT[sham] + rTMS[active]; Group-C: RECT[active] + rTMS[sham]). Frontal? and whole-brain glucose uptakes were assessed. We found that the RECT-modulated increases in frontal? correlated well with rACC glucose uptakes. The treatment responders demonstrated a significant increase in frontal? after RECT. Post-RECT frontal? had good sensitivity/specificity in predicting antidepressant responses to rTMS. Group-A had more reduction in total depression scores, had more responders, and was more likely to achieve remission than other groups (Group-A [41.6%] > Group-B [16.6%] > Group-C [0%], P < 0.05). A significant enhancement in the post-1st-rTMS frontal? was observed in Group-A responders but not in Group-B responders, supporting the argument that RECT-modulated rTMS augmented rTMS efficacy. In conclusion, this study suggests that manipulating pre-rTMS neural activity could predict and augment antidepressant effects to rTMS treatment.
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Highly efficient tandem organic light-emitting devices utilizing the connecting structure based on n-doped electron-transport layer/HATCN/hole-transport layer.
Appl Opt
PUBLISHED: 08-05-2014
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In this work, we conducted studies of tandem organic light-emitting devices (OLEDs) based on the connecting structure consisting of n-doped electron-transport layer (n-ETL)/1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN)/hole-transport layer. We investigated effects of different n-ETL materials and different HATCN thicknesses on characteristics of tandem OLEDs. Results show that the tandem OLEDs with n-BPhen and a 20 nm layer of HATCN in the connecting structure exhibited the best performance. With these, highly efficient and bright green phosphorescent two-emitting-unit tandem OLEDs, with drive voltages significantly lower than twice that of the single-unit benchmark device and current efficiencies higher than twice that of the single-unit benchmark device, were demonstrated.
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Evolutionarily conserved coupling of adaptive and excitable networks mediates eukaryotic chemotaxis.
Nat Commun
PUBLISHED: 07-30-2014
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Numerous models explain how cells sense and migrate towards shallow chemoattractant gradients. Studies show that an excitable signal transduction network acts as a pacemaker that controls the cytoskeleton to drive motility. Here we show that this network is required to link stimuli to actin polymerization and chemotactic motility and we distinguish the various models of chemotaxis. First, signalling activity is suppressed towards the low side in a gradient or following removal of uniform chemoattractant. Second, signalling activities display a rapid shut off and a slower adaptation during which responsiveness to subsequent test stimuli decline. Simulations of various models indicate that these properties require coupled adaptive and excitable networks. Adaptation involves a G-protein-independent inhibitor, as stimulation of cells lacking G-protein function suppresses basal activities. The salient features of the coupled networks were observed for different chemoattractants in Dictyostelium and in human neutrophils, suggesting an evolutionarily conserved mechanism for eukaryotic chemotaxis.
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Structural and Functional Analysis of Bacillus subtilis YisP Reveals a Role of Its Product in Biofilm Production.
Chem. Biol.
PUBLISHED: 07-08-2014
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YisP is involved in biofilm formation in Bacillus subtilis and has been predicted to produce C30 isoprenoids. We determined the structure of YisP and observed that it adopts the same fold as squalene and dehydrosqualene synthases. However, the first aspartate-rich motif found in essentially all isoprenoid synthases is aspartate poor in YisP and cannot catalyze head-to-head condensation reactions. We find that YisP acts as a phosphatase, catalyzing formation of farnesol from farnesyl diphosphate, and that it is the first phosphatase to adopt the fold seen in the head-to-head prenyl synthases. Farnesol restores biofilm formation in a ?yisp mutant and modifies lipid membrane structure similarly to the virulence factor staphyloxanthin. This work clarifies the role of YisP in biofilm formation and suggests an intriguing possibility that many of the YisP-like homologs found in other bacteria may also have interesting products and functions.
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Congenital right intermediate bronchial stenosis with carina trifurcation: successful management with slide tracheobronchial plasty.
Ann. Thorac. Surg.
PUBLISHED: 07-06-2014
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Congenital bronchial stenosis is rarely described and is difficult to manage. Here we report two cases of right intermediate bronchial stenosis (stenotic orifice with complete cartilage rings). Both cases were associated with ventricular septal defects, and a "trifurcation" pattern was found in both carinas. Both patients underwent surgical repair of the ventricular septal defects but could not be separated from ventilator support despite successful cardiac operations. Slide tracheobronchial plasty was applied to the right intermediate bronchus and lower trachea. After correction of the bronchial stenosis, both patients could be extubated and live without supplementary ventilation support.
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Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis.
Mol. Plant Pathol.
PUBLISHED: 06-30-2014
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Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway.
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Impact of Renal Insufficiency on Patients with Hepatocellular Carcinoma Undergoing Radiofrequency Ablation.
J. Gastroenterol. Hepatol.
PUBLISHED: 06-18-2014
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Renal insufficiency (RI) is commonly seen in patients with hepatocellular carcinoma (HCC). We aimed to investigate the impact of RI on the long-term survival of HCC patients undergoing radiofrequency ablation (RFA) and to determine the optimal staging strategy for these patients.
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Transcatheter aortic valve implantation: Anesthetic experience of retrograde transfemoral approach with CoreValve ReValving System.
Acta Anaesthesiol Taiwan
PUBLISHED: 06-18-2014
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Valvular aortic stenosis (AS) is a major cardiac valvular disease in geriatric people. Conventional treatment for severe AS is aortic valve replacement through surgery. However, many geriatric patients are considered inoperable due to higher risks for surgery and anesthesia. Transcatheter aortic valve implantation (TAVI), a less invasive procedure, has rapidly developed in recent years as an alternative management option for high-risk AS patients. Herein, we describe our anesthetic experience in the TAVI procedure.
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Plasmonic ITO-free polymer solar cell.
Opt Express
PUBLISHED: 06-13-2014
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The aluminum and sliver multilayered nano-grating structure is fabricated by laser interference lithography and the intervals between nanoslits is filled with modified PEDOT:PSS. The grating structured transparent electrode functions as the anti-reflection layer which not only decreases the reflected light but also increases the absorption of the active layer. The performances of P3HT:PC??BM solar cells are studied experimentally and theoretically in detail. The field intensities of the transverse magnetic (TM) and transverse electrical (TE) waves distributed in the active layer are simulated by rigorous coupled wave analysis (RCWA). The power conversion efficiency of the plasmonic ITO-free polymer solar cell can reach 3.64% which is higher than ITO based polymer solar cell with efficiency of 3.45%.
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Aggressive Therapeutic Strategies Improve the Survival of Hepatocellular Carcinoma Patients with Performance Status 1 or 2: A Propensity Score Analysis.
Ann. Surg. Oncol.
PUBLISHED: 06-11-2014
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Targeted therapy or chemotherapy is suggested as standard treatment for hepatocellular carcinoma (HCC) patients with performance status (PS) 1-2 according to the Barcelona Clinic Liver Cancer (BCLC) system. The underlying rationales have not been fully studied.
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Atoh1-dependent rhombic lip neurons are required for temporal delay between independent respiratory oscillators in embryonic mice.
Elife
PUBLISHED: 05-21-2014
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All motor behaviors require precise temporal coordination of different muscle groups. Breathing, for example, involves the sequential activation of numerous muscles hypothesized to be driven by a primary respiratory oscillator, the preBötzinger Complex, and at least one other as-yet unidentified rhythmogenic population. We tested the roles of Atoh1-, Phox2b-, and Dbx1-derived neurons (three groups that have known roles in respiration) in the generation and coordination of respiratory output. We found that Dbx1-derived neurons are necessary for all respiratory behaviors, whereas independent but coupled respiratory rhythms persist from at least three different motor pools after eliminating or silencing Phox2b- or Atoh1-expressing hindbrain neurons. Without Atoh1 neurons, however, the motor pools become temporally disorganized and coupling between independent respiratory oscillators decreases. We propose Atoh1 neurons tune the sequential activation of independent oscillators essential for the fine control of different muscles during breathing.DOI: http://dx.doi.org/10.7554/eLife.02265.001.
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Unconserved substrate-binding sites direct the stereoselectivity of medium-chain alcohol dehydrogenase.
Chem. Commun. (Camb.)
PUBLISHED: 05-20-2014
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Structure-guided design of substrate-binding pocket inversed the stereoselectivity of an NADH-dependent medium-chain alcohol dehydrogenase (MDR) from Prelog to anti-Prelog. The pocket-forming amino acids, especially the unconserved residues as hotspots, play critical roles in directing MDRs' stereoselectivity.
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Crystal structures of ligand-bound octaprenyl pyrophosphate synthase from Escherichia coli reveal the catalytic and chain-length determining mechanisms.
Proteins
PUBLISHED: 05-12-2014
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Octaprenyl pyrophosphate synthase (OPPs) catalyzes consecutive condensation reactions of one allylic substrate farnesyl pyrophosphate (FPP) and five homoallylic substrate isopentenyl pyrophosphate (IPP) molecules to form a C40 long-chain product OPP, which serves as a side chain of ubiquinone and menaquinone. OPPs belongs to the trans-prenyltransferase class of proteins. The structures of OPPs from Escherichia coli were solved in the apo-form as well as in complexes with IPP and a FPP thio-analog, FsPP, at resolutions of 2.2-2.6 Å, and revealed the detailed interactions between the ligands and enzyme. At the bottom of the active-site tunnel, M123 and M135 act in concert to form a wall which determines the final chain length. These results represent the first ligand-bound crystal structures of a long-chain trans-prenyltransferase and provide new information on the mechanisms of catalysis and product chain elongation. Proteins 2014. © 2014 Wiley Periodicals, Inc.
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Efficacy of prefrontal theta-burst stimulation in refractory depression: a randomized sham-controlled study.
Brain
PUBLISHED: 05-10-2014
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Theta-burst transcranial magnetic stimulation could modulate cortical excitability and has the potential to treat refractory depression. However, there has been a lack of large randomized studies of the antidepressant efficacy of different forms of theta-burst stimulation, such as intermittent and continuous theta-burst stimulation. A randomized sham-controlled study was conducted to investigate antidepressant efficacy of theta-burst stimulation and to compare efficacy among left-prefrontal intermittent theta-burst stimulation, right-prefrontal continuous theta-burst stimulation and a combination of them in patients showing different levels of antidepressant refractoriness. A group of 60 treatment-refractory patients with recurrent major depressive disorder were recruited and randomized to four groups (Group A: continuous theta-burst stimulation; Group B: intermittent theta-burst stimulation; Group C: a combination of continuous and intermittent theta-burst stimulation; and Group D: sham theta-burst stimulation; 15 patients were included in each group). After 2 weeks of theta-burst stimulation treatment, depression improved in all groups. Groups B and C had better antidepressant responses (as reflected by % decreases in depression score) than Groups A and D (P = 0.001, post hoc analysis: B > A, B > D, C > A, and C > D), even after controlling for age and refractoriness scores. The mean antidepressant effect was highest in Group C and followed by that in Group B. Additionally, a significant placebo effect was found in patients with low refractoriness; this disappeared in patients with moderate-to-high refractoriness. A significant correlation existed between refractoriness scores and treatment responses. Treatment refractoriness was a significant factor negatively predicting efficacy of theta-burst stimulation (P = 0.039). This randomized sham-controlled study demonstrated that active theta-burst stimulation is a well-tolerated form of repetitive transcranial magnetic stimulation and has good antidepressant efficacy, particularly in depressed subjects within a certain range of treatment refractoriness.
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Squalene synthase as a target for Chagas disease therapeutics.
PLoS Pathog.
PUBLISHED: 05-01-2014
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Trypanosomatid parasites are the causative agents of many neglected tropical diseases and there is currently considerable interest in targeting endogenous sterol biosynthesis in these organisms as a route to the development of novel anti-infective drugs. Here, we report the first x-ray crystallographic structures of the enzyme squalene synthase (SQS) from a trypanosomatid parasite, Trypanosoma cruzi, the causative agent of Chagas disease. We obtained five structures of T. cruzi SQS and eight structures of human SQS with four classes of inhibitors: the substrate-analog S-thiolo-farnesyl diphosphate, the quinuclidines E5700 and ER119884, several lipophilic bisphosphonates, and the thiocyanate WC-9, with the structures of the two very potent quinuclidines suggesting strategies for selective inhibitor development. We also show that the lipophilic bisphosphonates have low nM activity against T. cruzi and inhibit endogenous sterol biosynthesis and that E5700 acts synergistically with the azole drug, posaconazole. The determination of the structures of trypanosomatid and human SQS enzymes with a diverse set of inhibitors active in cells provides insights into SQS inhibition, of interest in the context of the development of drugs against Chagas disease.
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Surgical resection is better than transarterial chemoembolization for hepatocellular carcinoma beyond Milan criteria independent of performance status.
J. Gastrointest. Surg.
PUBLISHED: 04-14-2014
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Performance status is tightly linked with survival in patients with hepatocellular carcinoma (HCC). We investigated the impact of performance status on HCC patients beyond the Milan criteria receiving surgical resection (SR) or transarterial chemoembolization (TACE).
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Structural insights into enzymatic degradation of oxidized polyvinyl alcohol.
Chembiochem
PUBLISHED: 04-11-2014
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The ever-increasing production and use of polyvinyl alcohol (PVA) threaten our environment. Yet PVA can be assimilated by microbes in two steps: oxidation and cleavage. Here we report novel ?/?-hydrolase structures of oxidized PVA hydrolase (OPH) from two known PVA-degrading organisms, Sphingopyxis sp. 113P3 and Pseudomonas sp. VM15C, including complexes with substrate analogues, acetylacetone and caprylate. The active site is covered by a lid-like ?-ribbon. Unlike other esterase and amidase, OPH is unique in cleaving the C?C bond of ?-diketone, although it has a catalytic triad similar to that of most ?/?-hydrolases. Analysis of the crystal structures suggests a double-oxyanion-hole mechanism, previously only found in thiolase cleaving ?-ketoacyl-CoA. Three mutations in the lid region showed enhanced activity, with potential in industrial applications.
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Design and fabrication of birefringent nano-grating structure for circularly polarized light emission.
Opt Express
PUBLISHED: 04-11-2014
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Three different nano-grating structures are designed as phase retarders that can transform linearly polarized light to circularly polarized emission for the wavelengths of 488 nm, 532 nm and 632.8 nm, respectively. Gold based nano-grating structures with various periods are fabricated by utilizing laser interference lithography. The ellipticity of all circularly polarized emission can reach around 90% such that the structure has great potential in the applications of three-dimensional (3D) display. The effects of the slit width and metal thickness modulations are simulated by rigorous coupled wave analysis (RCWA) method. Besides, the field intensity and phase of the transmitted TM and TE waves are also simulated to understand their polarization characteristics.
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The stimulatory effects of alpha1-adrenergic receptors on TGF-beta1, IGF-1 and hyaluronan production in human skin fibroblasts.
Cell Tissue Res.
PUBLISHED: 04-10-2014
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Skin fibroblasts modulate tissue repair, wound healing and immunological responses. Adrenergic receptors (ARs) mediate important physiological functions, such as endocrine, metabolic and neuronal activity. In this study, the expression ?1A-ARs in human skin fibroblasts is examined and verified. Regulatory effects of ?1-agonist cirazoline on cell migration and the production of transforming growth factor ?1 (TGF-?1), insulin-like growth factor 1 (IGF-1), hyaluronan (HA), fibronectin and procollagen type I carboxy-terminal peptide (PIP) by human skin fibroblasts are assessed and validated. ?1A-AR mRNA and protein were found in human skin fibroblasts WS1. Exposure of cirazoline doubled skin fibroblast migration and the increase in cell migration was attenuated by ?1-antagonist prazosin. TGF-?1 mRNA and production were enhanced after exposure to cirazoline and IGF-1 production was also increased after treatment with cirazoline. Exposure to cirazoline also enhanced HA and PIP production. The increases in TGF-?1, IGF-1, HA and PIP production were partially abolished in fibroblasts transfected with ?1A-AR short interfering RNAs, indicating that ?1A-ARs are involved in the cirazoline-induced increases in TGF-?1, IGF-1, HA and PIP production. Thus, ?1A-ARs are stably expressed and stimulate cell migration and TGF-?1, IGF-1, HA and PIP production in human skin fibroblasts. Moreover, TGF-?1, IGF-1, HA and PIP production and the cell migration of human skin fibroblasts are possibly modulated by natural catecholamines produced by the endocrine system or sympathetic innervation, which could directly or indirectly participate in cytokine secretion, fibroblast migration and matrix production of wound healing in the skin.
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Radiofrequency Ablation is Better Than Surgical Resection in Patients With Hepatocellular Carcinoma Within the Milan Criteria and Preserved Liver Function: A Retrospective Study Using Propensity Score Analyses.
J. Clin. Gastroenterol.
PUBLISHED: 04-10-2014
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Radiofrequency ablation (RFA) and surgical resection (SR) are effective therapies for hepatocellular carcinoma (HCC) within the Milan criteria. We aimed to compare the treatment efficacy according to the liver functional reserve using propensity score analysis.
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Survival advantage of radiofrequency ablation over transarterial chemoembolization for patients with hepatocellular carcinoma and good performance status within the milan criteria.
Ann. Surg. Oncol.
PUBLISHED: 04-04-2014
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Performance status is closely linked with survival in patients with hepatocellular carcinoma (HCC). We evaluated the impact of performance status on patients with small HCC receiving radiofrequency ablation (RFA) versus transarterial chemoembolization (TACE).
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Structure, function and inhibition of ent-kaurene synthase from Bradyrhizobium japonicum.
Sci Rep
PUBLISHED: 04-03-2014
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We report the first X-ray crystal structure of ent-kaur-16-ene synthase from Bradyrhizobium japonicum, together with the results of a site-directed mutagenesis investigation into catalytic activity. The structure is very similar to that of the ? domains of modern plant terpene cyclases, a result that is of interest since it has been proposed that many plant terpene cyclases may have arisen from bacterial diterpene cyclases. The ent-copalyl diphosphate substrate binds to a hydrophobic pocket near a cluster of Asp and Arg residues that are essential for catalysis, with the carbocations formed on ionization being protected by Leu, Tyr and Phe residues. A bisphosphonate inhibitor binds to the same site. In the kaurene synthase from the moss Physcomitrella patens, 16-?-hydroxy-ent-kaurane as well as kaurene are produced since Leu and Tyr in the P. patens kaurene synthase active site are replaced by smaller residues enabling carbocation quenching by water. Overall, the results represent the first structure determination of a bacterial diterpene cyclase, providing insights into catalytic activity, as well as structural comparisons with diverse terpene synthases and cyclases which clearly separate the terpene cyclases from other terpene synthases having highly ?-helical structures.
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Crystallization and preliminary X-ray diffraction analysis of the S-adenosylhomocysteine hydrolase (SAHH) from Thermotoga maritima.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 03-28-2014
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S-Adenosylhomocysteine hydrolase (SAHH) catalyzes the reversible conversion of S-adenosylhomocysteine into adenosine and homocysteine. The SAHH from Thermotoga maritima (TmSAHH) was expressed in Escherichia coli and the recombinant protein was purified and crystallized. TmSAHH crystals belonging to space group C2, with unit-cell parameters a = 106.3, b = 112.0, c = 164.9?Å, ? = 103.5°, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.85?Å resolution. Initial phase determination by molecular replacement clearly indicated that the crystal contains one homotetramer per asymmetric unit. Further refinement of the crystal structure is in progress.
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Structural analysis of a glycoside hydrolase family 11 xylanase from Neocallimastix patriciarum: insights into the molecular basis of a thermophilic enzyme.
J. Biol. Chem.
PUBLISHED: 03-11-2014
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The catalytic domain of XynCDBFV, a glycoside hydrolase family 11 (GH11) xylanase from ruminal fungus Neocallimastix patriciarum previously engineered to exhibit higher specific activity and broader pH adaptability, holds great potential in commercial applications. Here, the crystal structures of XynCDBFV and its complex with substrate were determined to 1.27-1.43 ? resolution. These structures revealed a typical GH11 ?-jelly-roll fold and detailed interaction networks between the enzyme and ligands. Notably, an extended N-terminal region (NTR) consisting of 11 amino acids was identified in the XynCDBFV structure, which is found unique among GH11 xylanases. The NTR is attached to the catalytic core by hydrogen bonds and stacking forces along with a disulfide bond between Cys-4 and Cys-172. Interestingly, the NTR deletion mutant retained 61.5% and 19.5% enzymatic activity at 55 °C and 75 °C, respectively, compared with the wild-type enzyme, whereas the C4A/C172A mutant showed 86.8% and 23.3% activity. These results suggest that NTR plays a role in XynCDBFV thermostability, and the Cys-4/Cys-172 disulfide bond is critical to the NTR-mediated interactions. Furthermore, we also demonstrated that Pichia pastoris produces XynCDBFV with higher catalytic activity at higher temperature than Escherichia coli, in which incorrect NTR folding and inefficient disulfide bond formation might have occurred. In conclusion, these structural and functional analyses of the industrially favored XynCDBFV provide a molecular basis of NTR contribution to its thermostability.
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Preliminary X-ray diffraction analysis of a thermophilic ?-1,3-1,4-glucanase from Clostridium thermocellum.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 02-26-2014
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?-1,3-1,4-Glucanases catalyze the specific hydrolysis of internal ?-1,4-glycosidic bonds adjacent to the 3-O-substituted glucose residues in mixed-linked ?-glucans. The thermophilic glycoside hydrolase CtGlu16A from Clostridium thermocellum exhibits superior thermal profiles, high specific activity and broad pH adaptability. Here, the catalytic domain of CtGlu16A was expressed in Escherichia coli, purified and crystallized in the trigonal space group P3121, with unit-cell parameters a=b=74.5, c=182.9?Å, by the sitting-drop vapour-diffusion method and diffracted to 1.95?Å resolution. The crystal contains two protein molecules in an asymmetric unit. Further structural determination and refinement are in progress.
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Crystallization and preliminary X-ray diffraction analysis of (R)-carbonyl reductase from Candida parapsilosis.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 02-21-2014
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The NADH-dependent (R)-carbonyl reductase from Candida parapsilosis (RCR) catalyzes the asymmetric reduction of 2-hydroxyacetophenone (HAP) to produce (R)-1-phenyl-1,2-ethanediol [(R)-PED], which is used as a versatile building block for the synthesis of pharmaceuticals and fine chemicals. To gain insight into the catalytic mechanism, the structures of complexes of RCR with ligands, including the coenzyme, are important. Here, the recombinant RCR protein was expressed and purified in Escherichia coli and was crystallized in the presence of NAD+. The crystals, which belonged to the orthorhombic space group P2?2?2?, with unit-cell parameters a=85.64, b=106.11, c=145.55?Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.15?Å resolution. Initial model building indicates that RCR forms a homotetramer, consistent with previous reports of medium-chain-type alcohol dehydrogenases.
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Long-term cannabinoid type 2 receptor agonist therapy decreases bacterial translocation in rats with cirrhosis and ascites.
J. Hepatol.
PUBLISHED: 02-15-2014
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Intestinal hyperpermeability, impaired peritoneal macrophages (PMs) phagocytosis, and bacterial translocation (BT), resulting in increased systemic and local infection/inflammation such as spontaneous bacterial peritonitis (SBP) together with increased tumor necrosis factor-? (TNF?) levels, are all implicated in the pathogenesis of cirrhosis-related complications. Manipulation of the cannabinoid receptors (CB1R and CB2R), which are expressed on the gut mucosa and PMs, has been reported to modulate intestinal inflammation and systemic inflammatory cytokine release. Our study aims to explore the effects of chronic CB1R/CB2R agonist/antagonist treatments on relevant abnormalities in cirrhotic ascitic rats.
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Interleukin-1 receptor antagonist correlates with hepatic venous pressure gradient and predicts occurrence of overall complications and bacterial infections in patients with cirrhosis.
Hepatol. Res.
PUBLISHED: 02-11-2014
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The plasma levels of interleukin (IL)-1?, IL-1? and IL-1 receptor antagonist (IL-1Ra) are increased in cirrhotic patients. We aimed to investigate whether these cytokines correlate with hepatic venous pressure gradient (HVPG), the severity of liver cirrhosis and complications of cirrhosis.
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Surgical resection versus transarterial chemoembolization for hepatocellular carcinoma with portal vein tumor thrombosis: a propensity score analysis.
Ann. Surg. Oncol.
PUBLISHED: 02-06-2014
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The long-term survival in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) who received surgical resection (SR) or transarterial chemoembolization (TACE) remains unclear. We compared the efficacy of SR and TACE by using a propensity score analysis.
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Structure and inhibition of tuberculosinol synthase and decaprenyl diphosphate synthase from Mycobacterium tuberculosis.
J. Am. Chem. Soc.
PUBLISHED: 02-05-2014
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We have obtained the structure of the bacterial diterpene synthase, tuberculosinol/iso-tuberculosinol synthase (Rv3378c) from Mycobacterium tuberculosis , a target for anti-infective therapies that block virulence factor formation. This phosphatase adopts the same fold as found in the Z- or cis-prenyltransferases. We also obtained structures containing the tuberculosinyl diphosphate substrate together with one bisphosphonate inhibitor-bound structure. These structures together with the results of site-directed mutagenesis suggest an unusual mechanism of action involving two Tyr residues. Given the similarity in local and global structure between Rv3378c and the M. tuberculosis cis-decaprenyl diphosphate synthase (DPPS; Rv2361c), the possibility exists for the development of inhibitors that target not only virulence but also cell wall biosynthesis, based in part on the structures reported here.
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Benzodiazepine-associated hepatic encephalopathy significantly increased healthcare utilization and medical costs of Chinese cirrhotic patients: 7-year experience.
Dig. Dis. Sci.
PUBLISHED: 01-31-2014
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In cirrhosis, hypersensitivity to benzodiazepines (BZD) and precipitating hepatic encephalopathy (HE) have been reported. The aim of this study was to evaluate the safety, economic impact and modifiable factors that are associated with the excess risk of BZD-associated HE in cirrhotic patients.
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Crystallization and preliminary X-ray diffraction analysis of a novel ?-L-arabinofuranosidase (HypBA1) from Bifidobacterium longum.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 01-25-2014
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The ?-L-arabinofuranosidase (HypBA1) from Bifidobacterium longum JCM 1217 hydrolyzes the ?-1,2-linked arabinofuranose disaccharide to release L-arabinoses. HypBA1 was classified into glycoside hydrolase family 127 (GH127) by the CAZy website (http://www.cazy.org/). The enzyme was expressed in Escherichia coli and the purified recombinant protein was crystallized. Crystals belonging to the primitive hexagonal space group P3x21, with unit-cell parameters a = b = 75.9, c = 254.0Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.78Å resolution. A BLASTP search (http://blast.ncbi.nlm.nih.gov/) of the Protein Data Bank did not reveal any similar crystal structures. Structural determination by using SeMet MAD and MIR methods is in progress.
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Three-dimensional structure of an alkaline xylanase Xyn11A-LC from alkalophilic Bacillus sp. SN5 and improvement of its thermal performance by introducing arginines substitutions.
Biotechnol. Lett.
PUBLISHED: 01-22-2014
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The alkaline xylanase Xyn11A-LC from the alkalophilic Bacillus sp. SN5 was expressed in E. coli, purified and crystallized. The crystal structure was determined at a resolution of 1.49 Å. Xyn11A-LC has the ?-jelly roll structure typical of family 11 xylanases. To improve its thermostability and thermophilicity, a mutant SB3 was constructed by introducing three arginines on the different sides of the protein surface. SB3 increased the optimum temperature by 5 °C. The wild type and SB3 had the half-lives of 22 and 68 min at 65 °C at pH 8.0 (Tris/HCl buffer), respectively. CD spectroscopy revealed that the melting temperature (T m) of the wild type and SB3 were 55.3 and 66.9 °C, respectively. These results showed that the introduction of arginines enhance the thermophilicity and thermostability of Xyn11A-LC.
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Improving the specific activity of ?-mannanase from Aspergillus niger BK01 by structure-based rational design.
Biochim. Biophys. Acta
PUBLISHED: 01-22-2014
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?-Mannanase has found various biotechnological applications because it is capable of degrading mannans into smaller sugar components. A highly potent example is the thermophilic ?-mannanase from Aspergillus niger BK01 (ManBK), which can be efficiently expressed in industrial yeast strains and is thus an attractive candidate for commercial utilizations. In order to understand the molecular mechanism, which helps in strategies to improve the enzyme's performance that would meet industrial demands, 3D-structural information is a great asset. Here, we present the 1.57Å crystal structure of ManBK. The protein adopts a typical (?/?)8 fold that resembles the other GH5 family members. Polysaccharides were subsequently modeled into the substrate binding groove to identify the residues and structural features that may be involved in the catalytic reaction. Based on the structure, rational design was conducted to engineer ManBK in an attempt to enhance its enzymatic activity. Among the 23 mutants that we constructed, the most promising Y216W showed an 18±2.7% increase in specific activity by comparison with the wild type enzyme. The optimal temperature and heat tolerance profiles of Y216W were similar to those of the wild type, manifesting a preserved thermostability. Kinetic studies showed that Y216W has higher kcat values than the wild type enzyme, suggesting a faster turnover rate of catalysis. In this study we applied rational design to ManBK by using its crystal structure as a basis and identified the Y216W mutant that shows great potentials in industrial applications.
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Preliminary X-ray diffraction analysis of thermostable ?-1,4-xylanase from Streptomyces sp. S9.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 01-15-2014
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Xylanase, which catalyzes the random hydrolysis of internal xylosidic linkages, is a critical enzyme participating in xylan decomposition and has been widely applied in industrial utilizations. Xylanase isolated from the extremophilic Streptomyces sp. S9 (XynAS9) possesses broad adaptability to temperature and pH and thus is an attractive candidate in industrial applications. In particular, the major products of XynAS9 are xylose and xylobiose, which enable the subsequent bioconversion to be carried out with higher efficiency. Therefore, the three-dimensional structure of XynAS9 and its catalytic machinery are of great interest. Here, recombinant XynAS9 protein was expressed in Pichia pastoris, purified and crystallized. Crystals belonging to the hexagonal space group P6(5)22, with unit-cell parameters a = b = 80.9, c = 289.3?Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.08?Å resolution. Initial phase determination using molecular replacement indicated that the crystal contains one molecule in an asymmetric unit. Further model building and structural refinement are in progress.
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Robotic mitral valve repair in infective endocarditis.
J Thorac Dis
PUBLISHED: 01-06-2014
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Robotic mitral surgery is the most common robotic cardiac procedures. However, in mitral endocarditis the repair become more challenging especially in minimally approach. We applied robotic surgery in mitral endocarditis repair and reviewed our surgical methods and results.
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Injury Location and Mechanism for Complex Regional Pain Syndrome: A Nationwide Population-Based Case-Control Study in Taiwan.
Pain Pract
PUBLISHED: 01-03-2014
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Few studies have investigated the relationship between injury location, mechanism and their association with complex regional pain syndrome (CRPS). We conducted a nationwide database survey to explore this issue.
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Preventing Slips and Falls through Leisure-Time Physical Activity: Findings from a Study of Limited-Service Restaurants.
PLoS ONE
PUBLISHED: 01-01-2014
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Physical activity has been shown to be beneficial at improving health in some medical conditions and in preventing injury. Epidemiologic studies suggest that physical activity is one factor associated with a decreased risk for slips and falls in the older (?65 years) adult population. While the risk of slips and falls is generally lower in younger than in older adults; little is known of the relative contribution of physical activity in preventing slips and falls in younger adults. We examined whether engagement in leisure-time physical activity (LTPA) was protective of slips and falls among a younger/middle-aged (?50 years old) working population.
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A new Child-Turcotte-Pugh class 0 for patients with hepatocellular carcinoma: determinants, prognostic impact and ability to improve the current staging systems.
PLoS ONE
PUBLISHED: 01-01-2014
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Majority of patients with hepatocellular carcinoma (HCC) belonged to Child-Turcotte-Pugh (CTP) class A. We aimed to identify a new class of patients with very well-preserved liver function and analyze its impact on outcome prediction, tumor staging and treatment allocation.
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Decrypting cryptogenic hepatocellular carcinoma: clinical manifestations, prognostic factors and long-term survival by propensity score model.
PLoS ONE
PUBLISHED: 01-01-2014
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The clinical aspects of cryptogenic hepatocellular carcinoma (HCC), defined as HCC in patients without hepatitis B, C or alcoholism, are not clear. We investigated its clinical presentations, long-term survival and prognostic predictors.
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Risk Stratification and Outcome of Cardiac Surgery for Patients With Body Weight <2,500g in an Asian Center.
Circ. J.
PUBLISHED: 11-21-2013
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Background:?Cardiac surgery performed in patients with low body weight is a challenge for surgeons. Currently, such outcomes are mainly reported from European or North American centers. In this study, we review our cardiac surgery experience with neonates and infants weighing <2,500g. Methods and Results:?We included patients with a body weight <2,500g who received cardiac surgery between January 2008 and December 2012. The survival outcome was compared to that of patients with large body weight, and then the Risk Adjusted Classification for Congenital Heart Surgery (RACHS-1) categorization was used for operative risk stratification. In the 1,245 index operations, 53 patients (4.3%) were <2,500g. The mean body weight was 2,232g (range 1,320-2,500g). The hospital mortality rate was 20.7% (11/53). Most (85%) of the procedures were in RACHS-1 category ?3. The risk ratio was significantly higher in RACHS-1 category 3 (relative risk [RR]:6.2; 95% confidence interval [CI]:1.6-23.9) and 4 (RR:4.6; 95% CI:1.4-15.0), respectively, while it was not significantly different in category 2 (RR:1.02; 95% CI:1.01-1.02) and category 6 (RR:2.9; 95% CI:0.36-13.3). Conclusions:?Cardiac surgery performed on infants with low body weight is generally a complex procedure, but the results are acceptable. The risk was higher than that for patients with higher body weight in RACHS-1 category 3 and 4. Further investigation to improve the outcome of this high-risk group is needed.
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A Double-Blind Randomized Controlled Study to Evaluate the Efficacy of Low-Dose Oral Interferon-Alpha in Preventing Hepatitis C Relapse.
J. Interferon Cytokine Res.
PUBLISHED: 11-15-2013
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Low-dose oral interferon could exert immune-modulating effects in human. We conducted a clinical trial to investigate the efficacy of oral interferon-alpha in preventing hepatitis C relapse. Totally 169 genotype 1b chronic hepatitis C patients having achieved end-of-therapy virological clearance were randomized to receive interferon-alpha lozenge 500?IU/day (n=59), 1,500?IU/day (n=53), or placebo (n=57) for 24 weeks. Overall, no significant differences were found for the relapse rates in the 3 groups (P>0.05). However, in patients with fibroindex 1.4-1.7, relapse occurred in 1/12 (8.3%) 500?IU-group patients versus 9/21 (42.9%) patients of the other groups (P=0.05). In 158 patients receiving at least 4 weeks of oral interferon, significantly higher platelet count was found at the end of trial in the 500?IU group (P=0.003). In thrombocytopenic patients, a significantly expedited recovery of platelet count was found in the 500?IU group (P=0.002). No drug-related severe adverse events were reported. In conclusion, at 500?IU/day, oral interferon exerted a borderline suppression effect of virological relapse in chronic hepatitis C patients with mild liver fibrosis. Additionally, it significantly expedited platelet count recovery after the end of peginterferon therapy.
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Structural and Mutational Studies on the Unusual Substrate Specificity of meso-Diaminopimelate Dehydrogenase from Symbiobacterium thermophilum.
Chembiochem
PUBLISHED: 11-02-2013
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Wild-type meso-diaminopimelate dehydrogenase (DAPDH) is usually specific to the native substrate, meso-2,6-diaminopimelate. Recently, a DAPDH from Symbiobacterium thermophilum (StDAPDH) was found to exhibit expanded substrate specificity. As such, its crystal structures in apo form and in complex with NADP(+) and both NADPH and meso-DAP were investigated to reveal the structural basis of its unique catalytic properties. Structural analysis results show that StDAPDH should prefer an ordered kinetic catalytic mechanism. A second substrate entrance tunnel with Met152 at its bottleneck was found, through which pyruvate/D-alanine might bind and enter the catalytic cavity, providing some structural insights into its high activity toward pyruvate. The side chain of Met152 might interact with Asp92 and Asn253, thus affecting the domain motion and catalysis. These results offer useful information for understanding the unique catalytic properties of StDAPDH and guiding further engineering of this enzyme.
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Newly Emerging Mutations in the Matrix Genes of the Human Influenza A(H1N1)pdm09 and A(H3N2) Viruses Reduce the Detection Sensitivity of Real-Time Reverse Transcription-PCR.
J. Clin. Microbiol.
PUBLISHED: 10-23-2013
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New variants of the influenza A(H1N1)pdm09 and A(H3N2) viruses were detected in Taiwan between 2012 and 2013. Some of these variants were not detected in clinical specimens using a common real-time reverse transcription-PCR (RT-PCR) assay that targeted the conserved regions of the viral matrix (M) genes. An analysis of the M gene sequences of the new variants revealed that several newly emerging mutations were located in the regions where the primers or probes of the real-time RT-PCR assay bind; these included three mutations (G225A, T228C, and G238A) in the A(H1N1)pdm09 virus, as well as one mutation (C163T) in the A(H3N2) virus. These accumulated mismatch mutations, together with the previously identified C154T mutation of the A(H1N1)pdm09 virus and the C153T and G189T mutations of the A(H3N2) virus, result in a reduced detection sensitivity for the real-time RT-PCR assay. To overcome the loss of assay sensitivity due to mismatch mutations, we established a real-time RT-PCR assay using degenerate nucleotide bases in both the primers and probe and successfully increased the sensitivity of the assay to detect circulating variants of the human influenza A viruses. Our observations highlight the importance of the simultaneous use of different gene-targeting real-time RT-PCR assays for the clinical diagnosis of influenza.
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Overexpression of ferredoxin, PETF, enhances tolerance to heat stress in Chlamydomonas reinhardtii.
Int J Mol Sci
PUBLISHED: 08-31-2013
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Reactive oxygen species (ROS) produced by plants in adverse environments can cause damage to organelles and trigger cell death. Removal of excess ROS can be achieved through the ascorbate scavenger pathway to prevent plant cell death. The amount of this scavenger can be regulated by ferredoxin (FDX). Chloroplastic FDXs are electron transfer proteins that perform in distributing photosynthetic reducing power. In this study, we demonstrate that overexpression of the endogenous photosynthetic FDX gene, PETF, in Chlamydomonas reinhardtii could raise the level of reduced ascorbate and diminish H2O2 levels under normal growth conditions. Furthermore, the overexpressing PETF transgenic Chlamydomonas lines produced low levels of H2O2 and exhibited protective effects that were observed through decreased chlorophyll degradation and increased cell survival under heat-stress conditions. The findings of this study suggest that overexpression of PETF can increase the efficiency of ROS scavenging in chloroplasts to confer heat tolerance. The roles of PETF in the downregulation of the ROS level offer a method for potentially improving the tolerance of crops against heat stress.
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Structural and mutagenetic analyses of a 1,3-1,4-?-glucanase from Paecilomyces thermophila.
Biochim. Biophys. Acta
PUBLISHED: 08-11-2013
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The thermostable 1,3-1,4-?-glucanase PtLic16A from the fungus Paecilomyces thermophila catalyzes stringent hydrolysis of barley ?-glucan and lichenan with an outstanding efficiency and has great potential for broad industrial applications. Here, we report the crystal structures of PtLic16A and an inactive mutant E113A in ligand-free form and in complex with the ligands cellobiose, cellotetraose and glucotriose at 1.80Å to 2.25Å resolution. PtLic16A adopts a typical ?-jellyroll fold with a curved surface and the concave face forms an extended ligand binding cleft. These structures suggest that PtLic16A might carry out the hydrolysis via retaining mechanism with E113 and E118 serving as the nucleophile and general acid/base, respectively. Interestingly, in the structure of E113A/1,3-1,4-?-glucotriose complex, the sugar bound to the -1 subsite adopts an intermediate-like (?-anomeric) configuration. By combining all crystal structures solved here, a comprehensive binding mode for a substrate is proposed. These findings not only help understand the 1,3-1,4-?-glucanase catalytic mechanism but also provide a basis for further enzymatic engineering.
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Hepatocellular carcinoma in uremic patients: is there evidence for an increased risk of mortality?
J. Gastroenterol. Hepatol.
PUBLISHED: 07-28-2013
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The clinical aspects of patients with hepatocellular carcinoma (HCC) undergoing maintenance dialysis are largely unknown. We aimed to investigate the long-term survival and prognostic determinants of dialysis patients with HCC.
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Substrate binding to a GH131 ?-glucanase catalytic domain from Podospora anserina.
Biochem. Biophys. Res. Commun.
PUBLISHED: 07-12-2013
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?-Glucanases have been utilized widely in industry to treat various carbohydrate-containing materials. Recently, the Podospora anserina ?-glucanase 131A (PaGluc131A) was identified and classified to a new glycoside hydrolases GH131 family. It shows exo-?-1,3/exo-?-1,6 and endo-?-1,4 glucanase activities with a broad substrate specificity for laminarin, curdlan, pachyman, lichenan, pustulan, and cellulosic derivatives. Here we report the crystal structures of the PaGluc131A catalytic domain with or without ligand (cellotriose) at 1.8Å resolution. The cellotriose was clearly observed to occupy the +1 to +3 subsites in substrate binding cleft. The broadened substrate binding groove may explain the diverse substrate specificity. Based on our crystal structures, the GH131 family enzyme is likely to carry out the hydrolysis through an inverting catalytic mechanism, in which E99 and E139 are supposed to serve as the general base and general acid.
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Preliminary X-ray diffraction analysis of thermostable ?-1,4-mannanase from Aspergillus niger BK01.
Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun.
PUBLISHED: 07-05-2013
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?-1,4-Mannanase (?-mannanase) is a key enzyme in decomposing mannans, which are abundant components of hemicelluloses in the plant cell wall. Therefore, mannan hydrolysis is highly valuable in a wide array of industrial applications. ?-Mannanase isolated from Aspergillus niger BK01 (ManBK) was classified into glycoside hydrolase family GH5. ManBK holds great potential in biotechnological applications owing to its high thermostability. Here, ManBK was expressed and purified in Pichia pastoris and the recombinant protein was crystallized. Crystals belonging to the orthorhombic space group C222?, with unit-cell parameters a=93.58, b=97.05, c=147.84?Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 1.57?Å resolution. Structure determination using molecular-replacement methods is in progress.
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Interaction of motility, directional sensing, and polarity modules recreates the behaviors of chemotaxing cells.
PLoS Comput. Biol.
PUBLISHED: 07-01-2013
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Chemotaxis involves the coordinated action of separable but interrelated processes: motility, gradient sensing, and polarization. We have hypothesized that these are mediated by separate modules that account for these processes individually and that, when combined, recreate most of the behaviors of chemotactic cells. Here, we describe a mathematical model where the modules are implemented in terms of reaction-diffusion equations. Migration and the accompanying changes in cellular morphology are demonstrated in simulations using a mechanical model of the cell cortex implemented in the level set framework. The central module is an excitable network that accounts for random migration. The response to combinations of uniform stimuli and gradients is mediated by a local excitation, global inhibition module that biases the direction in which excitability is directed. A polarization module linked to the excitable network through the cytoskeleton allows unstimulated cells to move persistently and, for cells in gradients, to gradually acquire distinct sensitivity between front and back. Finally, by varying the strengths of various feedback loops in the model we obtain cellular behaviors that mirror those of genetically altered cell lines.
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Internet and telephonic IVR mixed-mode survey for longitudinal studies: choice, retention, and data equivalency.
Ann Epidemiol
PUBLISHED: 06-25-2013
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This study examined data equivalency and loss to follow-up rates from Internet and interactive voice response (IVR) system surveys in a prospective-cohort study.
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Randomized controlled trial of entecavir prophylaxis for rituximab-associated hepatitis B virus reactivation in patients with lymphoma and resolved hepatitis B.
J. Clin. Oncol.
PUBLISHED: 06-17-2013
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The role of antiviral prophylaxis in preventing hepatitis B virus (HBV) reactivation before rituximab-based chemotherapy in patients with lymphoma and resolved hepatitis B is unclear.
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Relationship of abdominal circumference and trunk length with spinal anesthesia level in the term parturient.
J Anesth
PUBLISHED: 06-06-2013
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We hypothesized that body shape metrics influence the anatomy of spinal canal and intraabdominal pressure in three dimensions. We explored the effects of abdominal circumference, trunk length, and their combination on the level of spinal anesthesia in the term parturient in this study.
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Upregulation of phosphorylated HSP27, PRDX2, GRP75, GRP78 and GRP94 in acquired middle ear cholesteatoma growth.
Int J Mol Sci
PUBLISHED: 05-07-2013
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Cholesteatoma is a destructive and expanding growth of keratinizing squamous epithelium in the middle ear or petrous apex. The molecular and cellular processes of the pathogenesis of acquired middle ear cholesteatoma have not been fully understood. In this study, comparative proteomic analysis was conducted to investigate the roles of specific proteins in the pathways regarding keratinocyte proliferation in cholesteatoma. The differential proteins were detected by comparing the two-dimension electrophoresis (2-DE) maps of the epithelial tissues of 12 attic cholesteatomas with those of retroauricular skins. There were 14 upregulated proteins in the epithelial tissues of cholesteatoma in comparison with retroauricular skin. The modulation of five crucial proteins, HSP27, PRDX2, GRP75, GRP78 and GRP94, was further determined by RT-PCR, Western blot and immunohistochemistry. Phosphorylation of HSP27 at Ser-82 was identified by mass spectroscopy. The results of this study suggested that phosphorylated HSP27 is the end expression of two potential signal-transduction pathways, and together with PRDX2, they are very likely involved in the proliferation of keratinocytes in cholesteatoma. Upregulations of GRP75, GRP78 and GRP94 in keratinocytes may be able to counter endoplasmic reticulum stress, to inhibit cell apoptosis, to prevent protein unfolding and to promote cholesteatoma growth.
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Development and validation of safety climate scales for mobile remote workers using utility/electrical workers as exemplar.
Accid Anal Prev
PUBLISHED: 04-22-2013
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The objective of this study was to develop and test the reliability and validity of a new scale designed for measuring safety climate among mobile remote workers, using utility/electrical workers as exemplar. The new scale employs perceived safety priority as the metric of safety climate and a multi-level framework, separating the measurement of organization- and group-level safety climate items into two sub-scales. The question of the emergence of shared perceptions among remote workers was also examined.
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Serum interferon gamma level predicts recurrence in hepatocellular carcinoma patients after curative treatments.
Int. J. Cancer
PUBLISHED: 04-17-2013
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Host immunity may have important role in the prognosis of hepatocellular carcinoma (HCC). The aim of this study was to evaluate the correlation between circulating immune regulators and clinical outcome in patients with HCC. Sixty-three HCC patients were prospectively enrolled. Serum levels of interleukin-10 (IL-10), transforming growth factor-beta (TGF-?), interferon-gamma (IFN-?) and interferon gamma-inducible protein 10 (IP-10) were measured, as well as the prevalence of regulatory T cells (Treg), NK(+) T cells, invariant natural killer T cells (iNKT), programmed cell death-1 (PD-1)(+) CD8(+) T cells, T helper 17 cells (Th17), CD69(+) and CD45RO(+) T cells in peripheral blood mononuclear cells (PBMC). Correlation between these immune regulators and clinical outcome were analyzed. A low serum IFN-? level (<50 pg/mL) was significantly associated tumor stage (BCLC stage B: 61.25% vs. stage A: 25%, p = 0.010) and tumor size (>5 cm: 53.8% vs. <5 cm: 25%, p = 0.047). Recurrence-free survival was evaluated in 48 patients receiving curative treatment of HCC. By multivariate analysis, BCLC stage [hazard ratio (HR) = 32.180, p < 0.001], tumor size (HR = 15.373, p = 0.005), AST (HR = 3.796, p = 0.011) and IFN-? (HR = 0.354, p = 0.018) levels were independent factors associated with recurrence-free survival. In conclusion, serum IFN-? level correlates with tumor stage and tumor size in HCC patients. Patients with lower baseline IFN-? levels have a higher risk of tumor recurrence after curative treatment. IFN-? may reflect host anti-tumor immunity and may be a potential marker of HCC recurrence after curative treatment.
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Promotion of wound healing using adipose-derived stem cells in radiation ulcer of a rat model.
J. Biomed. Sci.
PUBLISHED: 04-15-2013
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Wound healing is a complex biologic process that involves the integration of inflammation, mitosis, angiogenesis, synthesis, and remodeling of the extracellular matrix. However, some wounds fail to heal properly and become chronic. Although some simulated chronic wound models have been established, an efficient approach to treat chronic wounds in animal models has not been determined. The aim of this study was to develop a modified rat model simulating the chronic wounds caused by clinical radiation ulcers and examine the treatment of chronic wounds with adipose-derived stem cells.
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Concomitant slide tracheoplasty and cardiac operation for congenital tracheal stenosis associated with VACTERL.
Ann. Thorac. Surg.
PUBLISHED: 04-08-2013
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The association of congenital tracheal stenosis and tracheoesophageal (TE) fistula is rare. Here, we report 2 patients with tracheobronchial stenosis (complete cartilage ring) involving the lower trachea and right bronchus. Both patients had associated VACTERL (vertebral anomalies, anal atresia, cardiovascular anomalies, TE, renal, and limb defects) congenital cardiac defects and tracheal diverticula after repair of the TE fistula in type C esophageal atresia. The stenotic segment began at the orifice of the TE fistula, which became diverticula after the TE fistula was repaired. Concomitant repair of congenital cardiac defects and a slide tracheoplasty with elimination of the diverticula were performed successfully.
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Total tumor volume is a better marker of tumor burden in hepatocellular carcinoma defined by the Milan criteria.
World J Surg
PUBLISHED: 03-08-2013
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The Milan criteria are used to define small hepatocellular carcinoma (HCC) and to select patients for curative treatments. Total tumor volume (TTV) is an alternative parameter for tumor burden. We aimed to evaluate whether TTV is a feasible prognostic marker in HCC patients with upper boundary TTV of 65.5 cm(3), which is equivalent to a single 5 cm tumor nodule defined by the Milan criteria.
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What is Visualize?

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

How does it work?

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

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

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