JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Relative stability of the FCC and HCP polymorphs with interacting polymers.
Soft Matter
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
Recent work [Mahynski et al., Nat. Commun., 2014, 5, 4472] has demonstrated that the addition of long linear homopolymers thermodynamically biases crystallizing hard-sphere colloids to produce the hexagonal close-packed (HCP) polymorph over the closely related face-centered cubic (FCC) structure when the polymers and colloids are purely repulsive. In this report, we investigate the effects of thermal interactions on each crystal polymorph to explore the possibility of stabilizing the FCC crystal structure over the HCP. We find that the HCP polymorph remains at least as stable as its FCC counterpart across the entire range of interactions we explored, where interactions were quantified by the reduced second virial coefficient, -1.50 < B < 1.01. This metric conveniently characterizes the crossover from entropically to energetically dominated systems at B ? 0. While the HCP relies on its octahedral void arrangement for enhanced stability when B > 0, its tetrahedral voids produce a similar effect when B < 0 (i.e. when energetics dominate). Starting from this, we derive a mean-field expression for the free energy of an infinitely-dilute polymer adsorbed in the crystal phase for nonzero B. Our results reveal that co-solute biasing of a single polymorph can still be observed in experimentally realizable scenarios when the colloids and polymers have attractive interactions, and provide a possible explanation for the experimental finding that pure FCC crystals are elusive in these binary mixtures.
Related JoVE Video
Single-molecule analysis of the self-assembly process facilitated by host-guest interactions.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
The self-assembly process from a 1?:?1 to a 1?:?2 complex, facilitated by para-sulfonatocalix[6]arenes (SC6) as host and methyl viologen (MV(2+)) as guest, was analyzed at the single-molecule level through an ?-hemolysin nanopore. Especially, the assembled complex structures were discriminated in real time in the mixture of SC6 and MV(2+).
Related JoVE Video
Designing sociotechnical systems with cognitive work analysis: putting theory back into practice.
Ergonomics
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
Cognitive work analysis (CWA) is a framework of methods for analysing complex sociotechnical systems. However, the translation from the outputs of CWA to design is not straightforward. Sociotechnical systems theory provides values and principles for the design of sociotechnical systems which may offer a theoretically consistent basis for a design approach for use with CWA. This article explores the extent to which CWA and sociotechnical systems theory offer complementary perspectives and presents an abstraction hierarchy (AH), based on a review of literature, that describes an 'optimal' CWA and sociotechnical systems theory design system. The optimal AH is used to assess the extent to which current CWA-based design practices, uncovered through a survey of CWA practitioners, aligns with sociotechnical systems theory. Recommendations for a design approach that would support the integration of CWA and sociotechnical systems theory design values and principles are also derived.
Related JoVE Video
Neurocognitive functions and behavioral profiles in children with nephropathic cystinosis.
Saudi J Kidney Dis Transpl
PUBLISHED: 11-15-2014
Show Abstract
Hide Abstract
Children with nephropathic cystinosis (NCTN) have evidence of defective intellec-tual functions and behavioral disorders. This prospective study was performed to detect the cognitive dysfunctions in patients with this rare hereditary lysosomal storage disease, define their behavioral phenotypes, and study the findings on magnetic resonance imaging (MRI) of the brain. Thirteen patients with confirmed diagnosis of cystinosis (mean age ± SD 5.9 ± 3.0, range 1.5 - 12 years) were subjected to the Stanford Binet test, Porteus Maze test, Child Behavior Checklist, and MRI brain. Thirteen age- and sex-matched children served as the control subjects (mean age ± SD 5.9 ± 2.9, range 1.7 - 12 years). The intelligence quotient (IQ) was significantly lower in patients with cystinosis (P <0.001), with a significant defect in verbal (language, memory, and compre-hension) and non-verbal abilities (visual perception and visiospatial and motor performance). A discrepancy between both abilities was detected - the non-verbal ability being lower; however, it did not reach statistical significance. Furthermore, analysis revealed the visiospatial ability to be significantly lower compared to the visual perception. In comparison to healthy controls, children with NCTN had evidence of increased incidence of behavioral problems, mainly social (P = 0.023). An MRI of the brain revealed varying degrees of atrophic changes in seven patients. Patients with NCTN need a wider scope of attention and care, encompassing not only the metabolic multisystem derangement, but also the neuropsychological impairment in the context of multidisciplinary management. This approach is crucial in formulating comprehensive plans for social and educational rehabilitation.
Related JoVE Video
A Single-Gene Cause in 29.5% of Cases of Steroid-Resistant Nephrotic Syndrome.
J. Am. Soc. Nephrol.
PUBLISHED: 10-29-2014
Show Abstract
Hide Abstract
Steroid-resistant nephrotic syndrome (SRNS) is the second most frequent cause of ESRD in the first two decades of life. Effective treatment is lacking. First insights into disease mechanisms came from identification of single-gene causes of SRNS. However, the frequency of single-gene causation and its age distribution in large cohorts are unknown. We performed exon sequencing of NPHS2 and WT1 for 1783 unrelated, international families with SRNS. We then examined all patients by microfluidic multiplex PCR and next-generation sequencing for all 27 genes known to cause SRNS if mutated. We detected a single-gene cause in 29.5% (526 of 1783) of families with SRNS that manifested before 25 years of age. The fraction of families in whom a single-gene cause was identified inversely correlated with age of onset. Within clinically relevant age groups, the fraction of families with detection of the single-gene cause was as follows: onset in the first 3 months of life (69.4%), between 4 and 12 months old (49.7%), between 1 and 6 years old (25.3%), between 7 and 12 years old (17.8%), and between 13 and 18 years old (10.8%). For PLCE1, specific mutations correlated with age of onset. Notably, 1% of individuals carried mutations in genes that function within the coenzyme Q10 biosynthesis pathway, suggesting that SRNS may be treatable in these individuals. Our study results should facilitate molecular genetic diagnostics of SRNS, etiologic classification for therapeutic studies, generation of genotype-phenotype correlations, and the identification of individuals in whom a targeted treatment for SRNS may be available.
Related JoVE Video
Spatial pattern analysis for water quality in free-surface constructed wetland.
Water Sci. Technol.
PUBLISHED: 10-18-2014
Show Abstract
Hide Abstract
Free-surface constructed wetlands are known as a low-energy green technique to highly decrease a wide range of pollutants in wastewater and stormwater before discharge into natural water. In this study, two spatial analyses, principal factor analysis and hierarchical cluster analysis (HACA), were employed to interpret the effect of wetland on the water quality variables (WQVs) and to classify the wetland into groups with similar characteristics. Eleven WQVs were collected at the 17 sampling stations twice a month for 13 months. All sampling stations were classified by HACA into three clusters, with high, moderate, and low pollution areas. To improve the water quality, the performance of Cluster-III (micropool) is more significant than Cluster-I and Cluster-II. Implications of this study include potential savings of time and cost for long-term data monitoring purposes in the free-constructed wetland.
Related JoVE Video
Systematic and Open Identification of Researchers and Authors: Focus on Open Researcher and Contributor ID.
J. Korean Med. Sci.
PUBLISHED: 09-30-2014
Show Abstract
Hide Abstract
Unique identifiers of researchers and authors can help all stakeholders of scientific communications improve their workflows. There have been several attempts to establish professional networks of scholars and list their scholarly achievements on digital platforms. Some of these platforms such as Google Scholar, Web of Knowledge and PubMed are searched to pick relevant peer reviewers, assess authors' publication history or choose suitable candidates for research and academic projects. However, each of these hubs has its specific applications, limiting the universal use for permanent tagging of researcher profiles. The Open Researcher and Contributor ID (ORCID) initiative, launched in 2012, is aimed at registering scholarly contributors and averting the persistent ambiguity of recorded author names. The ORCID registry is growing fast and integrating with other ID-generating platforms, thereby increasing the functionality of the integrated systems. ORCID identifiers are increasingly used for selecting peer reviewers and acknowledging various scholarly contributions (e.g., published articles, reviewer comments, conference presentations). The initiative offers unique opportunities for transparent disclosures of author contributions and competing interests and improving ethical standards of research, editing, and publishing.
Related JoVE Video
Using the Event Analysis of Systemic Teamwork (EAST) to explore conflicts between different road user groups when making right hand turns at urban intersections.
Ergonomics
PUBLISHED: 09-10-2014
Show Abstract
Hide Abstract
Collisions between different types of road users at intersections form a substantial component of the road toll. This paper presents an analysis of driver, cyclist, motorcyclist and pedestrian behaviour at intersections that involved the application of an integrated suite of ergonomics methods, the Event Analysis of Systemic Teamwork (EAST) framework, to on-road study data. EAST was used to analyse behaviour at three intersections using data derived from an on-road study of driver, cyclist, motorcyclist and pedestrian behaviour. The analysis shows the differences in behaviour and cognition across the different road user groups and pinpoints instances where this may be creating conflicts between different road users. The role of intersection design in creating these differences in behaviour and resulting conflicts is discussed. It is concluded that currently intersections are not designed in a way that supports behaviour across the four forms of road user studied. Interventions designed to improve intersection safety are discussed. Practitioner Summary: Intersection safety currently represents a key road safety issue worldwide. This paper presents a novel application of a framework of ergonomics methods for studying differences in road user behaviour at intersections. The findings support development of interventions that consider all road users as opposed to one group in isolation.
Related JoVE Video
Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues.
Environ Sci Pollut Res Int
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
Human health is closely linked with soils via plants, grazers, or plant-based products. This study estimated plant-beneficial elements (macronutrients: K, P; secondary macronutrients: Ca, Mg; micronutrients: Mo, Mn, Na, Ni, Se) in both soils and shoots of two forage grass species (Eriophorum angustifolium and Lolium perenne) prevalent in the vicinity of a chemical industry complex (Estarreja, Portugal). Both soils and plants from the chemical industrial areas exhibited differential concentrations of the studied elements. In soils, the role of contamination was evidenced as insignificant in context of its impact on all the tested macro and secondary macronutrients except P, and micronutrients such as Mo and Ni. In forage grass plant shoots, the role of contamination was evidenced as insignificant in relation to its impact on all the tested macro and secondary macronutrients except K. Between the two forage grass plants, high Se-harboring L. perenne cannot be recommended for its use as animal feed.
Related JoVE Video
Juncus maritimus root biochemical assessment for its mercury stabilization potential in Ria de Aveiro coastal lagoon (Portugal).
Environ Sci Pollut Res Int
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
Major endogenous biochemical properties can make plants ideal agents for metal/metalloid-contaminated site cleanup. This study investigates the biochemistry of Juncus maritimus (Lam) roots for its high mercury (Hg) stabilization potential in the sediments of the Ria de Aveiro coastal lagoon (Portugal), which received Hg-rich effluents from a chlor-alkali industry between 1950 and 1994. J. maritimus plants were collected at a reference (R) site and three sites with the highest (L1), moderate (L2), and the lowest (L3) Hg contamination levels. The highest Hg-harboring/stabilizing J. maritimus roots at L1, exhibited significantly elevated damage endpoints (H2O2; lipid peroxidation, LPO; electrolyte leakage, EL; protein oxidation, PO; proline) which were accompanied by differential changes in H2O2-metabolizing defense system components (ascorbate peroxidase, catalase, glutathione peroxidase, glutathione S-transferase), glutathione reductase and the contents of both reduced and oxidized glutathione. Trends in measured endpoints reached maximum levels at L1 followed by L2 and L3. Cross-talks on root-Hg status and the studied biochemical traits revealed (a) high Hg-accrued elevations in oxidative stress as an obvious response; (b) Hg-stabilization potential of J. maritimus roots as a result of a successful mitigation of elevated high Hg-induced H2O2, and its anomalies such as LPO, EL, and PO; and (c) the induction of and a fine synchronization between non-glutathione and glutathione-based systems. Overall, the study unveiled biochemical mechanisms underlying root tolerance to Hg burden-accrued anomalies which, in turn, helped J. maritimus during Hg-stabilization.
Related JoVE Video
Too much is bad-an appraisal of phytotoxicity of elevated plant-beneficial heavy metal ions.
Environ Sci Pollut Res Int
PUBLISHED: 08-26-2014
Show Abstract
Hide Abstract
Heavy metal ions such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) are considered essential/beneficial for optimal plant growth, development, and productivity. However, these ions readily impact functions of many enzymes and proteins, halt metabolism, and exhibit phytotoxicity at supra-optimum supply. Nevertheless, the concentrations of these heavy metal ions are increasing in agricultural soils worldwide via both natural and anthropogenic sources that need immediate attention. Considering recent breakthroughs on Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: (a) overviews the status in soils and their uptake, transport, and significance in plants; (b) critically discusses their elevated level-mediated toxicity to both plant growth/development and cell/genome; (c) briefly cross talks on the significance of potential interactions between previous plant-beneficial heavy metal ions in plants; and (d) highlights so far unexplored aspects in the current context.
Related JoVE Video
Polycaprolactone/starch composite: Fabrication, structure, properties, and applications.
J Biomed Mater Res A
PUBLISHED: 08-18-2014
Show Abstract
Hide Abstract
Interests in the use of biodegradable polymers as biomaterials have grown. Among the different polymeric composites currently available, the blend of starch and polycaprolactone (PCL) has received the most attention since the 1980s. Novamont is the first company that manufactured a PCL/starch (SPCL) composite under the trademark Mater-Bi(®) . The properties of PCL (a synthetic, hydrophobic, flexible, expensive polymer with a low degradation rate) and starch (a natural, hydrophilic, stiff, abundant polymer with a high degradation rate) blends are interesting because of the composite components have completely different structures and characteristics. PCL can adjust humidity sensitivity of starch as a biomaterial; while starch can enhance the low biodegradation rate of PCL. Thus, by appropriate blending, SPCL can overcome important limitations of both PCL and starch components and promote controllable behavior in terms of mechanical properties and degradation which make it suitable for many biomedical applications. This paper reviewed the different fabrication and modification methods of the SPCL composite; different properties such as structural, physical, and chemical as well as degradation behavior; and different applications as biomaterials. This article is protected by copyright. All rights reserved.
Related JoVE Video
Minimising toxicity of cadmium in plants-role of plant growth regulators.
Protoplasma
PUBLISHED: 08-18-2014
Show Abstract
Hide Abstract
A range of man-made activities promote the enrichment of world-wide agricultural soils with a myriad of chemical pollutants including cadmium (Cd). Owing to its significant toxic consequences in plants, Cd has been one of extensively studied metals. However, sustainable strategies for minimising Cd impacts in plants have been little explored. Plant growth regulators (PGRs) are known for their role in the regulation of numerous developmental processes. Among major PGRs, plant hormones (such as auxins, gibberellins, cytokinins, abscisic acid, jasmonic acid, ethylene and salicylic acid), nitric oxide (a gaseous signalling molecule), brassinosteroids (steroidal phytohormones) and polyamines (group of phytohormone-like aliphatic amine natural compounds with aliphatic nitrogen structure) have gained attention by agronomist and physiologist as a sustainable media to induce tolerance in abiotic-stressed plants. Considering recent literature, this paper: (a) overviews Cd status in soil and its toxicity in plants, (b) introduces major PGRs and overviews their signalling in Cd-exposed plants, (c) appraises mechanisms potentially involved in PGR-mediated enhanced plant tolerance to Cd and (d) highlights key aspects so far unexplored in the subject area.
Related JoVE Video
Comparative study between Dermo, Pelite, and Seal-In X5 liners: effect on patient's satisfaction and perceived problems.
ScientificWorldJournal
PUBLISHED: 08-11-2014
Show Abstract
Hide Abstract
This study aimed to compare the effect of satisfaction and perceived problems between Pelite, Dermo with shuttle lock, and Seal-In X5 liners on the transtibial amputees.
Related JoVE Video
Biomechanics principle of elbow joint for transhumeral prostheses: comparison of normal hand, body-powered, myoelectric & air splint prostheses.
Biomed Eng Online
PUBLISHED: 08-03-2014
Show Abstract
Hide Abstract
Understanding of kinematics force applied at the elbow is important in many fields, including biomechanics, biomedical engineering and rehabilitation. This paper provides a comparison of a mathematical model of elbow joint using three different types of prosthetics for transhumeral user, and characterizes the forces required to overcome the passive mechanical of the prosthetics at the residual limb.
Related JoVE Video
Myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs.
Heart Vessels
PUBLISHED: 08-01-2014
Show Abstract
Hide Abstract
The aim of this study was to explore myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs. 24 male pigs (34.6 ± 1.3 kg) were randomly divided into three groups-control group, drug therapy group, and ECMO group. Myocardial infarction model was created in drug therapy group and ECMO group by ligating coronary artery. When cardiogenic shock occurred, drugs were given in drug therapy group and ECMO began to work in ECMO group. The pigs were killed 24 h after cardiogenic shock. Compared with in drug therapy group, left ventricular end-diastolic pressure in ECMO group decreased significantly 6 h after ligation (P < 0.05). At the end of the experiments, LV - dp/dt among three groups was significantly different, drug therapy group < ECMO group < control group. There was no difference in LV + dp/dt between drug therapy group and ECMO group. Compared with drug group, myocardial infarct size of ECMO group did not reduce significantly, but myocardial enzyme and troponin-I decreased significantly. Compared with drug therapy, ECMO improves left ventricular diastolic function, and may improve systolic function. ECMO cannot reduce myocardial infarct size without revascularization, but may have positive effects on ischemic areas by avoiding further injuring.
Related JoVE Video
Clinical utility of chitotriosidase enzyme activity in nephropathic cystinosis.
Orphanet J Rare Dis
PUBLISHED: 07-29-2014
Show Abstract
Hide Abstract
BackgroundNephropathic cystinosis is an inherited autosomal recessive lysosomal storage disorder characterized by the pathological accumulation and crystallization of cystine inside different cell types. WBC cystine determination forms the basis for the diagnosis and therapeutic monitoring with the cystine depleting drug (cysteamine). The chitotriosidase enzyme is a human chitinase, produced by activated macrophages. Its elevation is documented in several lysosomal storage disorders. Although, about 6% of Caucasians have enzyme deficiency due to homozygosity of 24-bp duplication mutation in the chitotriosidase gene, it is currently established as a screening marker and therapeutic monitor for Gaucher¿s disease.MethodsPlasma chitotriosidase activity was measured in 45 cystinotic patients, and compared with 87 healthy controls and 54 renal disease patients with different degrees of renal failure (CKD1-5). Chitotriosidase levels were also correlated with WBC cystine in 32 treated patients. Furthermore, we incubated control human macrophages in-vitro with different concentrations of cystine crystals and monitored the response of tumor necrosis factor-alpha (TNF-¿) and chitotriosidase activity. We also compared plasma chitotriosidase activity in cystinotic knocked-out (n¿=¿10) versus wild-type mice (n¿=¿10).ResultsPlasma chitotriosidase activity in cystinotic patients (0¿3880, median 163 nmol/ml/h) was significantly elevated compared to healthy controls (0¿90, median 18 nmol/ml/h) and to CKD patients (0¿321, median 52 nmol/ml/h), P¿<¿0.001 for both groups. Controls with decreased renal function had mild to moderate chitotriosidase elevations; however, their levels were significantly lower than in cystinotic patients with comparable degree of renal insufficiency. Chitotriosidase activity positively correlated with WBC cystine content for patients on cysteamine therapy (r¿=¿0.8), P¿<¿0.001. In culture, human control macrophages engulfed cystine crystals and released TNF-¿ into culture supernatant in a crystal concentration dependent manner. Chitotriosidase activity was also significantly increased in macrophage supernatant and cell-lysate. Furthermore, chitotriosidase activity was significantly higher in cystinotic knocked-out than in the wild-type mice, P¿=¿0.003.ConclusionsThis study indicates that cystine crystals are potent activators of human macrophages and that chitotriosidase activity is a useful marker for this activation and a promising clinical biomarker and therapeutic monitor for nephropathic cystinosis.
Related JoVE Video
Operative management of displaced acetabular fractures: an institutional experience with a midterm follow-up.
Ortop Traumatol Rehabil
PUBLISHED: 07-25-2014
Show Abstract
Hide Abstract
Operative management is considered to be the treatment of choice in acetabular fractures as this is the unique way of achieving precise anatomical reduction, stable internal fixation, and early mobilization of joint. With this background in mind we undertook a prospective study with an aim to assess the outcome of surgery in displaced acetabular fractures at our general orthopedic centre as a first experience.
Related JoVE Video
Prediction of water quality index in constructed wetlands using support vector machine.
Environ Sci Pollut Res Int
PUBLISHED: 07-08-2014
Show Abstract
Hide Abstract
Poor water quality is a serious problem in the world which threatens human health, ecosystems, and plant/animal life. Prediction of surface water quality is a main concern in water resource and environmental systems. In this research, the support vector machine and two methods of artificial neural networks (ANNs), namely feed forward back propagation (FFBP) and radial basis function (RBF), were used to predict the water quality index (WQI) in a free constructed wetland. Seventeen points of the wetland were monitored twice a month over a period of 14 months, and an extensive dataset was collected for 11 water quality variables. A detailed comparison of the overall performance showed that prediction of the support vector machine (SVM) model with coefficient of correlation (R (2))?=?0.9984 and mean absolute error (MAE)?=?0.0052 was either better or comparable with neural networks. This research highlights that the SVM and FFBP can be successfully employed for the prediction of water quality in a free surface constructed wetland environment. These methods simplify the calculation of the WQI and reduce substantial efforts and time by optimizing the computations.
Related JoVE Video
Technology efficacy in active prosthetic knees for transfemoral amputees: a quantitative evaluation.
ScientificWorldJournal
PUBLISHED: 07-07-2014
Show Abstract
Hide Abstract
Several studies have presented technological ensembles of active knee systems for transfemoral prosthesis. Other studies have examined the amputees' gait performance while wearing a specific active prosthesis. This paper combined both insights, that is, a technical examination of the components used, with an evaluation of how these improved the gait of respective users. This study aims to offer a quantitative understanding of the potential enhancement derived from strategic integration of core elements in developing an effective device. The study systematically discussed the current technology in active transfemoral prosthesis with respect to its functional walking performance amongst above-knee amputee users, to evaluate the system's efficacy in producing close-to-normal user performance. The performances of its actuator, sensory system, and control technique that are incorporated in each reported system were evaluated separately and numerical comparisons were conducted based on the percentage of amputees' gait deviation from normal gait profile points. The results identified particular components that contributed closest to normal gait parameters. However, the conclusion is limitedly extendable due to the small number of studies. Thus, more clinical validation of the active prosthetic knee technology is needed to better understand the extent of contribution of each component to the most functional development.
Related JoVE Video
Design and development of potential tissue engineering scaffolds from structurally different longitudinal parts of a bovine-femur.
Sci Rep
PUBLISHED: 07-02-2014
Show Abstract
Hide Abstract
The complex architecture of the cortical part of the bovine-femur was examined to develop potential tissue engineering (TE) scaffolds. Weight-change and X-ray diffraction (XRD) results show that significant phase transformation and morphology conversion of the bone occur at 500-750°C and 750-900°C, respectively. Another breakthrough finding was achieved by determining a sintering condition for the nucleation of hydroxyapatite crystal from bovine bone via XRD technique. Scanning electron microscopy results of morphological growth suggests that the concentration of polymer fibrils increases (or decreases, in case of apatite crystals) from the distal to proximal end of the femur. Energy-dispersive analysis of X-ray, Fourier transform infrared, micro-computer tomography, and mechanical studies of the actual composition also strongly support our microscopic results and firmly indicate the functionally graded material properties of bovine-femur. Bones sintered at 900 and 1000°C show potential properties for soft and hard TE applications, respectively.
Related JoVE Video
Effect of intra-articular hyaluronic injection on postural stability and risk of fall in patients with bilateral knee osteoarthritis.
ScientificWorldJournal
PUBLISHED: 06-19-2014
Show Abstract
Hide Abstract
Knee osteoarthritis is a common cause of disability which influences the quality of life. It is associated with impaired knee joint proprioception, which affects postural stability. Postural stability is critical for mobility and physical activities. Different types of treatment including nonsurgical and surgical are used for knee osteoarthritis. Hyaluronic acid injection is a nonsurgical popular treatment used worldwide. The aim of this study was to demonstrate the effect of hyaluronic acid injections on postural stability in individuals with bilateral knee osteoarthritis. Fifty patients aged between 50 and 70 years with mild and moderate bilateral knee osteoarthritis participated in our study. They were categorized into treatment (n = 25) and control (n = 25) groups. The treatment group received five weekly hyaluronic acid injections for both knees, whereas the control group did not receive any treatment. Postural stability and fall risk were assessed using the Biodex Stability System and clinical "Timed Up and Go" test. All the participants completed the study. The treatment group showed significant decrease in postural stability and fall risk scores after five hyaluronic acid injections. In contrast, the control group showed significant increase. This study illustrated that five intra-articular hyaluronic acid injections could significantly improve postural stability and fall risk in bilateral knee osteoarthritis patients. This trial is registered with: NCT02063373.
Related JoVE Video
Interface Stress in Socket/Residual Limb with Transtibial Prosthetic Suspension Systems During Locomotion on Slopes and Stairs.
Am J Phys Med Rehabil
PUBLISHED: 06-12-2014
Show Abstract
Hide Abstract
This study aimed to compare the effects of different suspension methods on the interface stress inside the prosthetic sockets of transtibial amputees when negotiating ramps and stairs.
Related JoVE Video
Effect of Geometrical Parameters on the Performance of Longitudinal Functionally Graded Femoral Prostheses.
Artif Organs
PUBLISHED: 05-21-2014
Show Abstract
Hide Abstract
This study aimed to assess the performance of different longitudinal functionally graded femoral prostheses. This study was also designed to develop an appropriate prosthetic geometric design for longitudinal functionally graded materials. Three-dimensional models of the femur and prostheses were developed and analyzed. The elastic modulus of these prostheses in the sagittal plane was adjusted along a gradient direction from the distal end to the proximal end. Furthermore, these prostheses were composed of titanium alloy and hydroxyapatite. Results revealed that strain energy, interface stress, and developed stress in the femoral prosthesis and the bone were influenced by prosthetic geometry and gradient index. In all of the prostheses with different geometries, strain energy increased as gradient index increased. Interface stress and developed stress decreased. The minimum principal stress and the maximum principal stress of the bone slightly increased as gradient index increased. Hence, the combination of the femoral prosthetic geometry and functionally graded materials can be employed to decrease stress shielding. Such a combination can also be utilized to achieve equilibrium in terms of the stress applied on the implanted femur constituents; thus, the lifespan of total hip replacement can be prolonged.
Related JoVE Video
Curcumin prevents diabetic nephropathy against inflammatory response via reversing caveolin-1 Tyr(14) phosphorylation influenced TLR4 activation.
Int. Immunopharmacol.
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
Inflammation is involved in the development and/or progression of diabetic nephropathy (DN). Curcumin has been reported for its anti-inflammation activity in DN. However, the mechanisms involved in the renoprotective effects of curcumin have not been clearly demonstrated. In this study, we hypothesized that curcumin affected high glucose (HG)-induced inflammation profiles in vivo and in vitro and then prevented renal injury in diabetic rats via reversing cav-1 Tyr(14) phosphorylation that influenced TLR4 activation. Streptozotocin (STZ)-induced diabetic rats received vehicle or curcumin for twelve weeks and podocytes were treated with HG in the presence or absence of curcumin in vitro. To further evaluate the effect of cav-1 phosphorylation at Tyr(14) on HG-induced podocyte inflammation response and TLR4 activation, a recombinant plasmid GFP-Cav-1 Y14F with a mutated phosphorylation site of cav-1, was transfected into cultured podocytes. In vivo, curcumin improved histological abnormalities and fibrosis of a diabetic kidney, inhibited renal inflammatory gene expression and reduced cav-1 phosphorylation at Tyr(14) and the expression of TLR4. Pretreatment of podocytes with curcumin reduced HG-stimulated production of proinflammatory cytokines, TLR4 and the phosphorylation of cav-1. But immunohistochemistry in rat kidney showed that the elevation of TLR4 expression is more evident in the renal interstitum than in the glomerulus where podocytes are located, and the possibility that the anti-inflammatory effects of curcumin on other cells in the kidney may be mediated through the same molecular pathways as in podocytes. Our study suggests that curcumin treatment ameliorates DN via inhibition of inflammatory gene expression by reversing caveolin-1 Tyr(14) phosphorylation that influenced TLR4 activation.
Related JoVE Video
Novosphingobium chloroacetimidivorans sp. nov., a chloroacetamide herbicide-degrading bacterium isolated from activated sludge.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 05-09-2014
Show Abstract
Hide Abstract
Strain BUT-14(T), a Gram-reaction-negative, non-spore-forming, ellipse-shaped bacterium, was isolated from activated sludge of a chloroacetamide-herbicides-manufacturing wastewater treatment facility. The strain was able to degrade more than 90% of butachlor, acetochlor and alachlor (100 mg l(-1)) within 5 days of incubation. The taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BUT-14(T) was a member of the genus Novosphingobium and showed the highest sequence similarities to Novosphingobium soli DSM 22821(T) (97.9%), N. naphthalenivorans KACC 15258(T) (97.4%), N. pentaromativorans JCM 12182(T) (97.4%) and N. barchaimii DSM 25411(T) (97.1%) and lower (<97%) sequence similarities to all other species of the genus Novosphingobium. Chemotaxonomic analysis revealed that strain BUT-14(T) possessed Q-10 as the predominant ubiquinone, spermidine as the major polyamine and C(18?:?1)?7c (46.9%), C(17?:?1)?6c (17.9%), summed feature 3, C(14?:?0) 2-OH (4.4%), C(15?:?0) 2-OH (3.1%) and C(16?:?0) (5.51%) as the major fatty acids. The polar lipids included lipid, glycolipid, phosphatidylglycerol, phospholipid, phosphatidylethanolamine, phosphatidylcholine, sphingoglycolipid and phospatidyldimethylethanolamine. Strain BUT-14(T) showed low DNA-DNA relatedness with N. soli DSM 22821(T) (41.5±2.9%), N. naphthalenivorans JCM 12182(T) (49.2±4.2%), N. pentaromativorans KACC 12295(T) (53.2±1.9%) and N. barchaimii DSM 25411 (51.2±4.5%). The DNA G+C content was 66±0.3 mol%. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic data and DNA-DNA hybridization supports the suggestion that strain BUT-14(T) represents a novel species of the genus Novosphingobium, for which the name Novosphingobium chloroacetimidivorans sp. nov. is proposed. The type strain is BUT-14(T) (?=?CCTCC AB 2013086(T)?=?KACC 17147(T)?=?JCM 19923(T)).
Related JoVE Video
Development of an air pneumatic suspension system for transtibial prostheses.
Sensors (Basel)
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
The suspension system and socket fitting of artificial limbs have major roles and vital effects on the comfort, mobility, and satisfaction of amputees. This paper introduces a new pneumatic suspension system that overcomes the drawbacks of current suspension systems in donning and doffing, change in volume during daily activities, and pressure distribution in the socket-stump interface. An air pneumatic suspension system (APSS) for total-contact sockets was designed and developed. Pistoning and pressure distribution in the socket-stump interface were tested for the new APSS. More than 95% of the area between each prosthetic socket and liner was measured using a Tekscan F-Scan pressure measurement which has developed matrix-based pressure sensing systems. The variance in pressure around the stump was 8.76 kPa. APSS exhibits less pressure concentration around the stump, improved pressure distribution, easy donning and doffing, adjustability to remain fitted to the socket during daily activities, and more adaptability to the changes in stump volume. The volume changes were adjusted by utility of air pressure sensor. The vertical displacement point and reliability of suspension were assessed using a photographic method. The optimum pressure in every level of loading weight was 55 kPa, and the maximum displacement was 6 mm when 90 N of weight was loaded.
Related JoVE Video
Transfemoral prosthesis suspension systems: a systematic review of the literature.
Am J Phys Med Rehabil
PUBLISHED: 04-19-2014
Show Abstract
Hide Abstract
The purpose of this study was to find the scientific evidence pertaining to various transfemoral suspension systems to provide selection criteria for clinicians. To this end, databases of PubMed, Web of Science, and ScienceDirect were explored. The following key words, as well as their combinations and synonyms, were used for the search: transfemoral prosthesis, prosthetic suspension, lower limb prosthesis, above-knee prosthesis, prosthetic liner, transfemoral, and prosthetic socket. The study design, research instrument, sampling method, outcome measures, and protocols of articles were reviewed. On the basis of the selection criteria, 16 articles (11 prospective studies and 5 surveys) were reviewed. The main causes of reluctance to prosthesis, aside from energy expenditure, were socket-related problems such as discomfort, perspiration, and skin problems. Osseointegration was a suspension option, yet it is rarely applied because of several drawbacks, such as extended rehabilitation process, risk for fracture, and infection along with excessive cost. In conclusion, no clinical evidence was found as a "standard" system of suspension and socket design for all transfemoral amputees. However, among various suspension systems for transfemoral amputees, the soft insert or double socket was favored by most users in terms of function and comfort.
Related JoVE Video
Comparison of various functionally graded femoral prostheses by finite element analysis.
ScientificWorldJournal
PUBLISHED: 04-17-2014
Show Abstract
Hide Abstract
This study is focused on finite element analysis of a model comprising femur into which a femoral component of a total hip replacement was implanted. The considered prosthesis is fabricated from a functionally graded material (FGM) comprising a layer of a titanium alloy bonded to a layer of hydroxyapatite. The elastic modulus of the FGM was adjusted in the radial, longitudinal, and longitudinal-radial directions by altering the volume fraction gradient exponent. Four cases were studied, involving two different methods of anchoring the prosthesis to the spongy bone and two cases of applied loading. The results revealed that the FG prostheses provoked more SED to the bone. The FG prostheses carried less stress, while more stress was induced to the bone and cement. Meanwhile, less shear interface stress was stimulated to the prosthesis-bone interface in the noncemented FG prostheses. The cement-bone interface carried more stress compared to the prosthesis-cement interface. Stair climbing induced more harmful effects to the implanted femur components compared to the normal walking by causing more stress. Therefore, stress shielding, developed stresses, and interface stresses in the THR components could be adjusted through the controlling stiffness of the FG prosthesis by managing volume fraction gradient exponent.
Related JoVE Video
Rapid detection of monogenic causes of childhood-onset steroid-resistant nephrotic syndrome.
Clin J Am Soc Nephrol
PUBLISHED: 04-17-2014
Show Abstract
Hide Abstract
In steroid-resistant nephrotic syndrome (SRNS), >21 single-gene causes are known. However, mutation analysis of all known SRNS genes is time and cost intensive. This report describes a new high-throughput method of mutation analysis using a PCR-based microfluidic technology that allows rapid simultaneous mutation analysis of 21 single-gene causes of SRNS in a large number of individuals.
Related JoVE Video
Stabilizing colloidal crystals by leveraging void distributions.
Nat Commun
PUBLISHED: 04-09-2014
Show Abstract
Hide Abstract
Colloids often crystallize into polymorphic structures, which are only separated by marginal differences in free energy. Due to this fact, the face-centred cubic and hexagonal close-packed hard-sphere morphologies, for example, usually crystallize simultaneously from a supersaturated solution. The resulting lack of long-range order in these polymorphic structures has been a significant barrier to the widespread application of these crystals in, for instance, photonic bandgap materials. Here, we report a simple method to stabilize one out of two competing polymorphs by exploiting the fact that they have significantly different spatial distributions of voids. We use a variety of polymeric additives whose geometries can be tuned such that their entropy loss, which is related to crystal void symmetries, is different in the two competing polymorphs. This, in turn, controls which polymorph is most thermodynamically stable, providing a generalizable means to stabilize a selected crystal polymorph from a suite of competing structures.
Related JoVE Video
Alleviation of salt-induced photosynthesis and growth inhibition by salicylic acid involves glycinebetaine and ethylene in mungbean (Vigna radiata L.).
Plant Physiol. Biochem.
PUBLISHED: 03-24-2014
Show Abstract
Hide Abstract
The influence of salicylic acid (SA) in alleviation of salt stress in mungbean (Vigna radiata L.) through modulation of glycinebetaine (GB) and ethylene was studied. SA application at 0.5 mM increased methionine (Met) and GB accumulation in plants concomitant with the suppression of ethylene formation by inhibiting 1-aminocyclopropane carboxylic acid synthase (ACS) activity more conspicuously under salt stress than no stress. The increased GB accumulation together with reduced ethylene under salt stress by SA application was associated with increased glutathione (GSH) content and lower oxidative stress. These positive effects on plant metabolism induced by SA application led to improved photosynthesis and growth under salt stress. These results suggest that SA induces GB accumulation through increased Met and suppresses ethylene formation under salt stress and enhances antioxidant system resulting in alleviation of adverse effects of salt stress on photosynthesis and growth. These effects of SA were substantiated by the findings that application of SA-analogue, 2, 6, dichloro-isonicotinic acid (INA) and ethylene biosynthesis inhibitor, aminoethoxyvinylglycine (AVG) resulted in similar effects on Met, GB, ethylene production, photosynthesis and growth under salt stress. Future studies on the interaction between SA, GB and ethylene could be exploited for adaptive responses of plants under salt stress.
Related JoVE Video
Clinical and ultrasonographical characterization of childhood cystic kidney diseases in Egypt.
Ren Fail
PUBLISHED: 03-24-2014
Show Abstract
Hide Abstract
Renal cystic disorders (RCD) constitute an important and leading cause of end-stage renal disease (ESRD) in children. It can be acquired or inherited; isolated or associated with extrarenal manifestations. The precise diagnosis represents a difficult clinical challenge.
Related JoVE Video
Nocardioides soli sp. nov., a carbendazim-degrading bacterium isolated from soil under the long-term application of carbendazim.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 03-20-2014
Show Abstract
Hide Abstract
The taxonomic status of a carbendazim-degrading strain, mbc-2(T), isolated from soil under the long-term application of carbendazim in China was determined by means of a polyphasic study. The cells were Gram-stain-positive, motile and rod-shaped. Strain mbc-2(T) grew optimally at pH 7.0, 30-35 °C and in the presence of 1% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain mbc-2(T) fell within the genus Nocardioides, forming a coherent cluster with the type strain of Nocardioides hankookensis, with which it exhibited 16S rRNA gene sequence similarity values of 97.9%. The chemotaxonomic properties of strain mbc-2(T) were consistent with those of the genus Nocardioides: the cell-wall peptidoglycan type was based on ll-2,6-diaminopimelic acid, the predominant menaquinone was MK-8 (H4) and the major fatty acid was iso-C(16?:?0). The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, unknown phospholipids and an unknown aminolipid. The DNA G+C content was 72 mol%. Strain mbc-2(T) exhibited DNA-DNA relatedness values of 12.5±1.5%, 23.7±2.7% and 26.3±3.2% with respect to Nocardioides hankookensis DS-30(T), Nocardioides aquiterrae GW-9(T) and Nocardioides pyridinolyticus OS4(T). On the basis of the data obtained, strain mbc-2(T) represents a novel species of the genus Nocardioides, for which the name Nocardioides soli sp. nov. is proposed. The type strain is mbc-2(T) (?=?KACC 17152(T)?=?CCTCC AB 2012934(T)).
Related JoVE Video
Flow-induced demixing of polymer-colloid mixtures in microfluidic channels.
J Chem Phys
PUBLISHED: 03-11-2014
Show Abstract
Hide Abstract
We employ extensive computer simulations to study the flow behavior of spherical, nanoscale colloids in a viscoelastic solvent under Poiseuille flow. The systems are confined in a slit-like microfluidic channel, and viscoelasticity is introduced explicitly through the inclusion of polymer chains on the same length scale as the dispersed solute particles. We systematically study the effects of flow strength and polymer concentration, and identify a regime in which the colloids migrate to the centerline of the microchannel, expelling the polymer chains to the sides. This behavior was recently identified in experiments, but a detailed understanding of the underlying physics was lacking. To this end, we provide a detailed analysis of this phenomenon and discuss ways to maximize its effectiveness. The focusing mechanism can be exploited to separate and capture particles at the sub-micrometer scale using simple microfluidic devices, which is a crucial task for many biomedical applications, such as cell counting and genomic mapping.
Related JoVE Video
Fabrication and characterization of DLC coated microdimples on hip prosthesis heads.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 03-10-2014
Show Abstract
Hide Abstract
Diamond like carbon (DLC) is applied as a thin film onto substrates to obtain desired surface properties such as increased hardness and corrosion resistance, and decreased friction and wear rate. Microdimple is an advanced surface modification technique enhancing the tribological performance. In this study, DLC coated microdimples were fabricated on hip prosthesis heads and their mechanical, material and surface properties were characterized. An Electro discharge machining (EDM) oriented microdrilling was utilized to fabricate a defined microdimple array (diameter of 300 µm, depth of 70 µm, and pitch of 900 µm) on stainless steel (SS) hip prosthesis heads. The dimpled surfaces were then coated by hydrogenated amorphous carbon (a-C:H) and tetrahedral amorphous carbon (Ta-C) layers by using a magnetron sputtering technology. A preliminary tribology test was conducted on these fabricated surfaces against a ceramic ball in simulated hip joint conditions. It was found that the fabricated dimples were perpendicular to the spherical surfaces and no cutting-tools wear debris was detected inside the individual dimples. The a-C:H and Ta-C coatings increased the hardness at both the dimple edges and the nondimpled region. The tribology test showed a significant reduction in friction coefficient for coated surfaces regardless of microdimple arrays: the lowest friction coefficient was found for the a-C:H samples (µ = 0.084), followed by Ta-C (µ = 0.119), as compared to the SS surface (µ = 0.248). © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014.
Related JoVE Video
Self-correction in biomedical publications and the scientific impact.
Croat. Med. J.
PUBLISHED: 03-01-2014
Show Abstract
Hide Abstract
To analyze mistakes and misconduct in multidisciplinary and specialized biomedical journals.
Related JoVE Video
Xenophilus arseniciresistens sp. nov., an arsenite-resistant bacterium isolated from soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 02-28-2014
Show Abstract
Hide Abstract
A Gram-reaction-negative, aerobic, motile, rod-shaped, arsenite [As(III)]-resistant bacterium, designated strain YW8(T), was isolated from agricultural soil. 16S rRNA gene sequence analysis showed over 97% sequence similarity to strains of the environmental species Xenophilus azovorans, Xenophilus aerolatus, Simplicispira metamorpha, Variovorax soli, and Xylophilus ampelinus. However, the phylogenetic tree indicated that strain YW8(T) formed a separate clade from Xenophilus azovorans. DNA-DNA hybridization experiments showed that the DNA-DNA relatedness values between strain YW8(T) and its closest phylogenetic neighbours were below 24.2-35.5%, which clearly separated the strain from these closely related species. The major cellular fatty acids of strain YW8(T) were C(16?:?0), C(17?:?0) cyclo, C(18?:?1)?7c, and summed feature 3(C(16?:?1)?6c and/or C(16?:?1)?7c). The genomic DNA G+C content was 69.3 mol%, and the major respiratory quinone was ubiquinone-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unknown phospholipids, an unknown polar lipid and phosphatidylserine. The major polyamines were 2-hydroxyputrescine and putrescine. On the basis of morphological, physiological and biochemical characteristics, phylogenetic position, DNA-DNA hybridization and chemotaxonomic data, strain YW8(T) is considered to represent a novel species of the genus Xenophilus, for which the name Xenophilus arseniciresistens sp. nov. is proposed; the type strain is YW8(T) (?=?CCTCC AB2012103(T)?=?KACC 16853(T)).
Related JoVE Video
Development and performance of a new prosthesis system using ultrasonic sensor for wrist movements: a preliminary study.
Biomed Eng Online
PUBLISHED: 02-27-2014
Show Abstract
Hide Abstract
The design and performance of a new development prosthesis system known as biomechatronics wrist prosthesis is presented in this paper. The prosthesis system was implemented by replacing the Bowden tension cable of body powered prosthesis system using two ultrasonic sensors, two servo motors and microcontroller inside the prosthesis hand for transradial user.
Related JoVE Video
Endothelial cell responses in terms of adhesion, proliferation, and morphology to stiffness of polydimethylsiloxane elastomer substrates.
J Biomed Mater Res A
PUBLISHED: 02-26-2014
Show Abstract
Hide Abstract
Extracellular environments can regulate cell behavior because cells can actively sense their mechanical environments. This study evaluated the adhesion, proliferation and morphology of endothelial cells on polydimethylsiloxane (PDMS)/alumina (Al2 O3 ) composites and pure PDMS. The substrates were prepared from pure PDMS and its composites with 2.5, 5, 7.5, and 10 wt % Al2 O3 at a curing temperature of 50°C for 4 h. The substrates were then characterized by mechanical, structural, and morphological analyses. The cell adhesion, proliferation, and morphology of cultured bovine aortic endothelial (BAEC) cells on substrate materials were evaluated by using resazurin assay and 1,1'-dioctadecyl-1,3,3,3',3'-tetramethylindocarbocyanine perchlorate-acetylated LDL (Dil-Ac-LDL) cell staining, respectively. The composites (PDMS/2.5, 5, 7.5, and 10 wt % Al2 O3 ) exhibited higher stiffness than the pure PDMS substrate. The results also revealed that stiffer substrates promoted endothelial cell adhesion and proliferation and also induced spread morphology in the endothelial cells compared with lesser stiff substrates. Statistical analysis showed that the effect of time on cell proliferation depended on stiffness. Therefore, this study concludes that the addition of different Al2 O3 percentages to PDMS elevated substrate stiffness which in turn increased endothelial cell adhesion and proliferation significantly and induced spindle shape morphology in endothelial cells. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014.
Related JoVE Video
The effects of prosthetic foot type and visual alteration on postural steadiness in below-knee amputees.
Biomed Eng Online
PUBLISHED: 02-26-2014
Show Abstract
Hide Abstract
Achieving independent upright posture has known to be one of the main goals in rehabilitation following lower limb amputation. The purpose of this study was to compare postural steadiness of below knee amputees with visual alterations while wearing three different prosthetic feet.
Related JoVE Video
What the drivers do and do not tell you: using verbal protocol analysis to investigate driver behaviour in emergency situations.
Ergonomics
PUBLISHED: 02-20-2014
Show Abstract
Hide Abstract
Although task analysis of pedestrian detection can provide us with useful insights into how a driver may behave in emergency situations, the cognitive elements of driver decision-making are less well understood. To assist in the design of future Advanced Driver Assistance Systems, such as Autonomous Emergency Brake systems, it is essential that the cognitive elements of the driving task are better understood. This paper uses verbal protocol analysis in an exploratory fashion to uncover the thought processes underlying behavioural outcomes represented by hard data collected using the Southampton University Driving Simulator.
Related JoVE Video
Brain glutathione redox system significance for the control of silica-coated magnetite nanoparticles with or without mercury co-exposures mediated oxidative stress in European eel (Anguilla anguilla L.).
Environ Sci Pollut Res Int
PUBLISHED: 02-19-2014
Show Abstract
Hide Abstract
This in vitro study investigates the impact of silica-coated magnetite particles (Fe3O4@SiO2/SiDTC, hereafter called IONP; 2.5 mg L(-1)) and its interference with co-exposure to persistent contaminant (mercury, Hg; 50 ?g L(-1)) during 0, 2, 4, 8, 16, 24, 48, and 72 h on European eel (Anguilla anguilla) brain and evaluates the significance of the glutathione (GSH) redox system in this context. The extent of damage (membrane lipid peroxidation, measured as thiobarbituric acid reactive substances, TBARS; protein oxidation, measured as reactive carbonyls, RCs) decreased with increasing period of exposure to IONP or IONP + Hg which was accompanied with differential responses of glutathione redox system major components (glutathione reductase, GR; glutathione peroxidase, GPX; total GSH, TGSH). The occurrence of antagonism between IONP and Hg impacts was evident at late hour (72 h), where significantly decreased TBARS and RC levels and GR and glutathione sulfo-transferase (GST) activity imply the positive effect of IONP + Hg concomitant exposure against Hg-accrued negative impacts [vs. early (2 h) hour of exposure]. A period of exposure-dependent IONP alone and IONP + Hg joint exposure-accrued impact was perceptible. Additionally, increased susceptibility of the GSH redox system to increased period of exposure to Hg was depicted, where insufficiency of elevated GR for the maintenance of TGSH required for membrane lipid and cellular protein protection was displayed. Overall, a fine-tuning among brain glutathione redox system components was revealed controlling IONP + Hg interactive impacts successfully.
Related JoVE Video
Intelligent screening systems for cervical cancer.
ScientificWorldJournal
PUBLISHED: 02-11-2014
Show Abstract
Hide Abstract
Advent of medical image digitalization leads to image processing and computer-aided diagnosis systems in numerous clinical applications. These technologies could be used to automatically diagnose patient or serve as second opinion to pathologists. This paper briefly reviews cervical screening techniques, advantages, and disadvantages. The digital data of the screening techniques are used as data for the computer screening system as replaced in the expert analysis. Four stages of the computer system are enhancement, features extraction, feature selection, and classification reviewed in detail. The computer system based on cytology data and electromagnetic spectra data achieved better accuracy than other data.
Related JoVE Video
Ethylene production is associated with alleviation of cadmium-induced oxidative stress by sulfur in mustard types differing in ethylene sensitivity.
Ecotoxicol. Environ. Saf.
PUBLISHED: 02-07-2014
Show Abstract
Hide Abstract
We studied the response of ethylene-sensitive (Pusa Jai Kisan) and ethylene-insensitive (SS2) mustard (Brassica juncea) cultivars to 0, 0.5, 1.0 and 2.0 mM SO?(2-), and the effect of 1.0 mM SO?(2-) was studied in the amelioration of 50 µM cadmium (Cd). The Cd-induced oxidative stress and Cd accumulation were greater in SS2 than Pusa Jai Kisan, but sulfur (S) application alleviated Cd-induced oxidative stress more prominently in Pusa Jai Kisan by increasing S-metabolism and synthesis of reduced glutathione (GSH) and ethylene production; and promoted photosynthesis and plant dry mass under Cd stress. The ethylene-sensitive cultivar responded more to S treatment under Cd stress and showed increased activity of antioxidant system resulting in increased photosynthesis and growth. Cadmium treatment resulted in rapid increase in ethylene formation which adversely influenced photosynthesis and plant dry mass. However, S and ethephon application to Cd-treated plants lowered ethylene formation to optimal range responsible for maximal GSH synthesis and protection against Cd-induced oxidative stress. The similarity of the effectiveness of 1.0 mM SO?(2-) with 200 µL L(-1) ethylene source as ethephon in alleviation of 50 µM Cd further verifies that differential alleviation of Cd toxicity in the two cultivars by S was dependent on ethylene production. The results suggest that ethylene production determines Cd stress alleviation by S via regulatory interaction with antioxidant metabolism. Thus, ethylene production and sensitivity bear a prominent role in alleviation of Cd stress by S and can be used as a criterion for developing Cd tolerant genotypes.
Related JoVE Video
Validating the strategies analysis diagram: assessing the reliability and validity of a formative method.
Appl Ergon
PUBLISHED: 01-23-2014
Show Abstract
Hide Abstract
The Strategies Analysis Diagram (SAD) is a recently developed method to model the range of possible strategies available for activities in complex sociotechnical systems. Previous applications of the new method have shown that it can effectively identify a comprehensive range of strategies available to humans performing activity within a particular system. A recurring criticism of Ergonomics methods is however, that substantive evidence regarding their performance is lacking. For a method to be widely used by other practitioners such evaluations are necessary. This article presents an evaluation of criterion-referenced validity and test-retest reliability of the SAD method when used by novice analysts. The findings show that individual analyst performance was average. However, pooling the individual analyst outputs into a group model increased the reliability and validity of the method. It is concluded that the SAD method's reliability and validity can be assured through the use of a structured process in which analysts first construct an individual model, followed by either another analyst pooling the individual results or a group process pooling individual models into an agreed group model.
Related JoVE Video
Quantitative analysis of human ankle characteristics at different gait phases and speeds for utilizing in ankle-foot prosthetic design.
Biomed Eng Online
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Ankle characteristics vary in terms of gait phase and speed change. This study aimed to quantify the components of ankle characteristics, including quasi-stiffness and work in different gait phases and at various speeds.
Related JoVE Video
Exploring schema-driven differences in situation awareness between road users: an on-road study of driver, cyclist and motorcyclist situation awareness.
Ergonomics
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Collisions between different road users make a substantial contribution to road trauma. Although evidence suggests that different road users interpret the same road situations differently, it is not clear how road users' situation awareness differs, nor is it clear which differences might lead to conflicts. This article presents the findings from an on-road study conducted to examine driver, motorcyclist and cyclist situation awareness in different road environments. The findings suggest that, in addition to minor differences in the structure of different road users' situation awareness (i.e. amount of information and how it is integrated), the actual content of situation awareness in terms of road user schemata, the resulting interaction with the world and the information underpinning situation awareness is markedly different. Further examination indicates that the differences are likely to be compatible along arterial roads, shopping strips and at roundabouts, but that they may create conflicts between different road users at intersections. Interventions designed to support compatible situation awareness and behaviour between different road users are discussed.
Related JoVE Video
Oxidative stress status, antioxidant metabolism and polypeptide patterns in Juncus maritimus shoots exhibiting differential mercury burdens in Ria de Aveiro coastal lagoon (Portugal).
Environ Sci Pollut Res Int
PUBLISHED: 01-20-2014
Show Abstract
Hide Abstract
This study assessed the oxidative stress status, antioxidant metabolism and polypeptide patterns in salt marsh macrophyte Juncus maritimus shoots exhibiting differential mercury burdens in Ria de Aveiro coastal lagoon at reference and the sites with highest, moderate and the lowest mercury contamination. In order to achieve these goals, shoot-mercury burden and the responses of representative oxidative stress indices, and the components of both non-glutathione- and glutathione-based H2O2-metabolizing systems were analyzed and cross-talked with shoot-polypeptide patterns. Compared to the reference site, significant elevations in J. maritimus shoot mercury and the oxidative stress indices such as H2O2, lipid peroxidation, electrolyte leakage and reactive carbonyls were maximum at the site with highest followed by moderate and the lowest mercury contamination. Significantly elevated activity of non-glutathione-based H2O2-metabolizing enzymes such as ascorbate peroxidase and catalase accompanied the studied damage-endpoint responses, whereas the activity of glutathione-based H2O2-scavenging enzymes glutathione peroxidase and glutathione sulfo-transferase was inhibited. Concomitantly, significantly enhanced glutathione reductase activity and the contents of both reduced and oxidized glutathione were perceptible in high mercury-exhibiting shoots. It is inferred that high mercury-accrued elevations in oxidative stress indices were obvious, where non-glutathione-based H2O2-decomposing enzyme system was dominant over the glutathione-based H2O2-scavenging enzyme system. In particular, the glutathione-based H2O2-scavenging system failed to coordinate with elevated glutathione reductase which in turn resulted into increased pool of oxidized glutathione and the ratio of oxidized glutathione-to-reduced glutathione. The substantiation of the studied oxidative stress indices and antioxidant metabolism with approximately 53-kDa polypeptide warrants further studies.
Related JoVE Video
Postural stability characteristics of transtibial amputees wearing different prosthetic foot types when standing on various support surfaces.
ScientificWorldJournal
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
This study aimed to evaluate the effects of prosthetic foot types on the postural stability among transtibial amputees when standing on different support surfaces.
Related JoVE Video
Involvement of ethylene in reversal of salt-inhibited photosynthesis by sulfur in mustard.
Physiol Plant
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
Sulfur (S) assimilation results in the synthesis of cysteine (Cys), a common metabolite for the formation of both reduced glutathione (GSH) and ethylene. Thus, ethylene may have regulatory interaction with GSH in the alleviation of salt stress. The involvement of ethylene in the alleviation of salt stress by S application was studied in mustard (Brassica juncea cv. Pusa Jai Kisan). First, the effects of 0, 0.5, 1.0 and 2.0?mM SO4 (2) (-) were studied on photosynthetic and growth parameters to ascertain the S requirement as sufficient-S and excess-S for the plant. In further experiments, the effects of sufficient-S (1?mM SO4 (2) (-) ) and excess-S (2?mM SO4 (2) (-) ) were studied on the alleviation of salt stress-induced by 100?mM NaCl, and ethylene involvement in the alleviation of salt stress by S. Under non-saline condition, excess-S increased ethylene with less content of Cys and GSH and adversely affected photosynthesis and growth. In contrast, excess-S maximally alleviated salt stress due to high demand for S and optimal ethylene formation, which maximally increased GSH and promoted photosynthesis and growth. The involvement of ethylene in S-mediated alleviation of salt stress was further substantiated by the reversal of the effects of excess-S on photosynthesis by aminoethoxyvinylglycine (AVG), ethylene biosynthesis inhibitor. The studies suggest that plants respond differentially to the S availability under non-saline and salt stress and excess-S was more potential in the alleviation of salt stress. Further, ethylene regulates plants' response and excess S-induced alleviation of salt stress and promotion of photosynthesis.
Related JoVE Video
Transdifferentiation of differentiated ovary into functional testis by long-term treatment of aromatase inhibitor in Nile tilapia.
Endocrinology
PUBLISHED: 01-17-2014
Show Abstract
Hide Abstract
Females with differentiated ovary of a gonochoristic fish, Nile tilapia, were masculinized by long-term treatment with an aromatase inhibitor (Fadrozole) in the present study. The reversed gonads developed into functional testes with fertile sperm. The longer the fish experienced sex differentiation, the longer treatment time was needed for successful sex reversal. Furthermore, Fadrozole-induced sex reversal, designated as secondary sex reversal (SSR), was successfully rescued by supplement of exogenous 17?-estradiol. Gonadal histology, immunohistochemistry, transcriptome, and serum steroid level were analyzed during SSR. The results indicated that spermatogonia were transformed from oogonia or germline stem cell-like cells distributed in germinal epithelium, whereas Leydig and Sertoli cells probably came from the interstitial cells and granulosa cells of the ovarian tissue, respectively. The transdifferentiation of somatic cells, as indicated by the appearance of doublesex- and Mab-3-related transcription factor 1 (pre-Sertoli cells) and cytochrome P450, family 11, subfamily B, polypeptide 2 (pre-Leydig cells)-positive cells in the ovary, provided microniche for the transdifferentiation of germ cells. Decrease of serum 17?-estradiol was detected earlier than increase of serum 11-ketotestosterone, indicating that decrease of estrogen was the cause, whereas increase of androgen was the consequence of SSR. The sex-reversed gonad displayed more similarity in morphology and histology with a testis, whereas the global gene expression profiles remained closer to the female control. Detailed analysis indicated that transdifferentiation was driven by suppression of female pathway genes and activation of male pathway genes. In short, SSR provides a good model for study of sex reversal in teleosts and for understanding of sex determination and differentiation in nonmammalian vertebrates.
Related JoVE Video
Metal/metalloid stress tolerance in plants: role of ascorbate, its redox couple, and associated enzymes.
Protoplasma
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
The enhanced generation of reactive oxygen species (ROS) under metal/metalloid stress is most common in plants, and the elevated ROS must be successfully metabolized in order to maintain plant growth, development, and productivity. Ascorbate (AsA) is a highly abundant metabolite and a water-soluble antioxidant, which besides positively influencing various aspects in plants acts also as an enigmatic component of plant defense armory. As a significant component of the ascorbate-glutathione (AsA-GSH) pathway, it performs multiple vital functions in plants including growth and development by either directly or indirectly metabolizing ROS and its products. Enzymes such as monodehydroascorbate reductase (MDHAR, EC 1.6.5.4) and dehydroascorbate reductase (DHAR, EC 1.8.5.1) maintain the reduced form of AsA pool besides metabolically controlling the ratio of AsA with its oxidized form (dehydroascorbate, DHA). Ascorbate peroxidase (APX, EC 1.11.1.11) utilizes the reduced AsA pool as the specific electron donor during ROS metabolism. Thus, AsA, its redox couple (AsA/DHA), and related enzymes (MDHAR, DHAR, and APX) cumulatively form an AsA redox system to efficiently protect plants particularly against potential anomalies caused by ROS and its products. Here we present a critical assessment of the recent research reports available on metal/metalloid-accrued modulation of reduced AsA pool, AsA/DHA redox couple and AsA-related major enzymes, and the cumulative significance of these antioxidant system components in plant metal/metalloid stress tolerance.
Related JoVE Video
New method for the isolation of endothelial cells from large vessels.
Cytotherapy
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
Numerous protocols for the isolation of bovine aortic endothelial cells have been described in the previous literature. However, these protocols prevent researchers from obtaining the pure population of endothelial cells. Thus, this study aimed to develop a new and economical method for the isolation of pure endothelial cells by introducing a new strategy to the enzymatic digestion method proposed by previous researchers.
Related JoVE Video
Evaluation of new suspension system for limb prosthetics.
Biomed Eng Online
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
Good prosthetic suspension system secures the residual limb inside the prosthetic socket and enables easy donning and doffing. This study aimed to introduce, evaluate and compare a newly designed prosthetic suspension system (HOLO) with the current suspension systems (suction, pin/lock and magnetic systems).
Related JoVE Video
Roseomonas rhizosphaerae sp. nov., a triazophos-degrading bacterium isolated from soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
A novel aerobic, non-spore-forming, non-motile, catalase- and oxidase-positive, Gram-stain-negative, coccoid to short-rod-shaped bacterial strain, designated YW11(T), was isolated from soil under long-term application of triazophos. The strain was able to hydrolyse triazophos. Strain YW11(T) grew at 15-40 °C (optimum at 28 °C), at pH 5.0-8.0 (optimum at pH 7.5) and with 0-5.0?% (w/v) NaCl (optimum at 0.5?%). The major respiratory quinone was ubiquinone 10 (Q-10) and the major cellular fatty acids were C18?:?1?7c, C16?:?0, C18?:?1 2-OH and C18?:?0. The genomic DNA G+C content of strain YW11(T) was 69.6±0.5 mol%. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, an unknown glycolipid and two unknown aminolipids. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain YW11(T) was a member of the genus Roseomonas, and showed the highest sequence similarity to Roseomonas cervicalis KACC 11686(T) (97.9?%) and Roseomonas aestuarii KACC 19645(T) (97.8?%) and then to Roseomonas ludipueritiae KACC 13843(T) (96.9?%). Strain YW11(T) showed low DNA-DNA relatedness with R. cervicalis KACC 11686(T) (32.3±2.9?%), R. aestuarii KACC 16549(T) (28.2±2.6?%) and R. ludipueritiae KACC 13843(T) (30.2±2.6?%). Based on the results of phylogenetic analysis and DNA-DNA hybridization, the whole-cell fatty acid composition as well as biochemical characteristics, strain YW11(T) was clearly distinguished from all recognized species of the genus Roseomonas and should be assigned to a novel species of the genus Roseomonas, for which the name Roseomonas rhizosphaerae sp. nov. is proposed. The type strain is YW11(T) (?=?KACC 17225(T)?=?CCTCC AB2013041(T)).
Related JoVE Video
Halimione portulacoides (L.) physiological/biochemical characterization for its adaptive responses to environmental mercury exposure.
Environ. Res.
PUBLISHED: 01-06-2014
Show Abstract
Hide Abstract
This study investigates largely unexplored physiological/biochemical strategies adopted by salt marsh macrophyte Halimione portulacoides (L.) Aellen for its adaptation/tolerance to environmental mercury (Hg)-exposure in a coastal lagoon prototype. To this end, a battery of damage (hydrogen peroxide, H2O2; thiobarbituric acid reactive substances, TBARS; electrolyte leakage, EL; reactive carbonyls; osmolyte, proline) and defense [ascorbate peroxidase, APX; catalase, CAT; glutathione peroxidase, GPX; glutathione sulfo-transferase, GST; glutathione reductase, GR; reduced and oxidized glutathione (GSH and GSSG, respectively), and GSH/GSSG ratio] biomarkers, and polypeptide patterns were assessed in H. portulacoides roots and leaves at reference (R) and the sites with highest (L1), moderate (L2) and the lowest (L3) Hg-contamination gradients. Corresponding to the Hg-burdens, roots and leaves exhibited a differential modulation of damage- and defense-endpoints and polypeptide-patterns. Roots exhibiting the highest Hg-burden (at L3) failed to maintain a coordination among enzymatic-defense endpoint responses which resulted into increased oxidation of reduced glutathione (GSH) pool, lowest GSH/GSSG (oxidized) ratio and partial H2O2-metabolism. In contrast, the highest Hg-burden exhibiting leaves (at L1) successfully maintained a coordination among enzymatic-defense endpoints responses which resulted into decreased GSH-oxidation, enhanced reduced GSH pool and GSH/GSSG ratio and lower extent of damage. Additionally, increased leaf-carotenoids content with increasing Hg-burden implies its protective function. H. portulacoides leaf-polypeptides did not respond as per its Hg-burden but the roots did. Overall, the physiological/biochemical characterization of below (roots)- and above (leaves)-ground organs (studied in terms of damage and defense endpoints, and polypeptides modulation) revealed the adaptive responses of H. portulacoides to environmental Hg at whole plant level which cumulatively helped this plant to sustain and execute its Hg-remediation potential.
Related JoVE Video
Assessment of cadmium accumulation, toxicity, and tolerance in Brassicaceae and Fabaceae plants--implications for phytoremediation.
Environ Sci Pollut Res Int
PUBLISHED: 01-04-2014
Show Abstract
Hide Abstract
This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg(-1) soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd concentrations can be of great help in elaborating the innovative plant-based remediation technologies for metal/metalloid-contaminated sites.
Related JoVE Video
Internal fixation of shaft humerus fractures by dynamic compression plate or interlocking intramedullary nail: a prospective, randomised study.
Strategies Trauma Limb Reconstr
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
Compare the results of internal fixation of shaft of humerus fractures using dynamic compression plating (DCP) or antegrade interlocking intramedullary nail (IMN). Fifty patients with diaphyseal fracture of the shaft of the humerus and fulfilling the inclusion criterion were randomly assigned to one of the two groups. Twenty-five patients were managed with closed antegrade interlocking intramedullary nail, and 25 underwent open reduction and internal fixation using dynamic compression plating. The mean age of patients with IMN fixation was 37.28 years (SD 12.26) and 37.72 years (SD 12.70) for those who underwent plating. Road traffic accident was the most common mode of injury in both groups. There was a statistically significant difference between the two groups with respect to duration of hospital stay, operative time and blood loss. There was no significant difference between the two groups in terms of union or complications. The functional assessment at the end of 1 year between the two groups did not show any significant difference in outcome. Antegrade interlocking IMN and DCP fixation are comparable when managing diaphyseal shaft of humerus fractures with respect to union rates and complications. Although shoulder related complications are more in the IMN group, however, it is associated with shorter hospital stay, lesser operative time and less blood loss. This makes interlocking IMN an effective option in managing these fractures.
Related JoVE Video
Extracellular matrix integrity affects the mechanical behaviour of in-situ chondrocytes under compression.
J Biomech
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
Cartilage lesions change the microenvironment of cells and may accelerate cartilage degradation through catabolic responses from chondrocytes. In this study, we investigated the effects of structural integrity of the extracellular matrix (ECM) on chondrocytes by comparing the mechanics of cells surrounded by an intact ECM with cells close to a cartilage lesion using experimental and numerical methods. Experimentally, 15% nominal compression was applied to bovine cartilage tissues using a light-transmissible compression system. Target cells in the intact ECM and near lesions were imaged by dual-photon microscopy. Changes in cell morphology (N(cell)=32 for both ECM conditions) were quantified. A two-scale (tissue level and cell level) Finite Element (FE) model was also developed. A 15% nominal compression was applied to a non-linear, biphasic tissue model with the corresponding cell level models studied at different radial locations from the centre of the sample in the transient phase and at steady state. We studied the Green-Lagrange strains in the tissue and cells. Experimental and theoretical results indicated that cells near lesions deform less axially than chondrocytes in the intact ECM at steady state. However, cells near lesions experienced large tensile strains in the principal height direction, which are likely associated with non-uniform tissue radial bulging. Previous experiments showed that tensile strains of high magnitude cause an up-regulation of digestive enzyme gene expressions. Therefore, we propose that cartilage degradation near tissue lesions may be due to the large tensile strains in the principal height direction applied to cells, thus leading to an up-regulation of catabolic factors.
Related JoVE Video
Ethylene reverses photosynthetic inhibition by nickel and zinc in mustard through changes in PS II activity, photosynthetic nitrogen use efficiency, and antioxidant metabolism.
Protoplasma
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
We investigated the influence of exogenously sourced ethylene (200 ?L L(-1) ethephon) in the protection of photosynthesis against 200 mg kg(-1) soil each of nickel (Ni)- and zinc (Zn)-accrued stress in mustard (Brassica juncea L.). Plants grown with Ni or Zn but without ethephon exhibited increased activity of 1-aminocyclopropane carboxylic acid synthase, and ethylene with increased oxidative stress measured as H2O2 content and lipid peroxidation compared with control plants. The oxidative stress in Ni-grown plants was higher than Zn-grown plants. Under metal stress, ethylene protected photosynthetic potential by efficient PS II activity and through increased activity of ribulose-1,5-bisphosphate carboxylase and photosynthetic nitrogen use efficiency (P-NUE). Application of 200 ?L L(-1) ethephon to Ni- or Zn-grown plants significantly alleviated toxicity and reduced the oxidative stress to a greater extent together with the improved net photosynthesis due to induced activity of ascorbate peroxidase and glutathione (GSH) reductase, resulting in increased production of reduced GSH. Ethylene formation resulting from ethephon application alleviated Ni and Zn stress by reducing oxidative stress caused by stress ethylene production and maintained increased GSH pool. The involvement of ethylene in reversal of photosynthetic inhibition by Ni and Zn stress was related to the changes in PS II activity, P-NUE, and antioxidant capacity was confirmed using ethylene action inhibitor, norbornadiene.
Related JoVE Video
Demographics and Genetic Variability of the New World Bollworm (Helicoverpa zea) and the Old World Bollworm (Helicoverpa armigera) in Brazil.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Helicoverpa armigera is one of the primary agricultural pests in the Old World, whereas H. zea is predominant in the New World. However, H. armigera was first documented in Brazil in 2013. Therefore, the geographical distribution, range of hosts, invasion source, and dispersal routes for H. armigera are poorly understood or unknown in Brazil. In this study, we used a phylogeographic analysis of natural H. armigera and H. zea populations to (1) assess the occurrence of both species on different hosts; (2) infer the demographic parameters and genetic structure; (3) determine the potential invasion and dispersal routes for H. armigera within the Brazilian territory; and (4) infer the geographical origin of H. armigera. We analyzed partial sequence data from the cytochrome c oxidase subunit I (COI) gene. We determined that H. armigera individuals were most prevalent on dicotyledonous hosts and that H. zea were most prevalent on maize crops, based on the samples collected between May 2012 and April 2013. The populations of both species showed signs of demographic expansion, and no genetic structure. The high genetic diversity and wide distribution of H. armigera in mid-2012 are consistent with an invasion period prior to the first reports of this species in the literature and/or multiple invasion events within the Brazilian territory. It was not possible to infer the invasion and dispersal routes of H. armigera with this dataset. However, joint analyses using sequences from the Old World indicated the presence of Chinese, Indian, and European lineages within the Brazilian populations of H. armigera. These results suggest that sustainable management plans for the control of H. armigera will be challenging considering the high genetic diversity, polyphagous feeding habits, and great potential mobility of this pest on numerous hosts, which favor the adaptation of this insect to diverse environments and control strategies.
Related JoVE Video
Berberine Improves Kidney Function in Diabetic Mice via AMPK Activation.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. Effective therapies to prevent the development of this disease are required. Berberine (BBR) has several preventive effects on diabetes and its complications. However, the molecular mechanism of BBR on kidney function in diabetes is not well defined. Here, we reported that activation of AMP-activated protein kinase (AMPK) is required for BBR-induced improvement of kidney function in vivo. AMPK phosphorylation and activity, productions of reactive oxygen species (ROS), kidney function including serum blood urea nitrogen (BUN), creatinine clearance (Ccr), and urinary protein excretion, morphology of glomerulus were determined in vitro or in vivo. Exposure of cultured human glomerulus mesangial cells (HGMCs) to BBR time- or dose-dependently activates AMPK by increasing the thr172 phosphorylation and its activities. Inhibition of LKB1 by siRNA or mutant abolished BBR-induced AMPK activation. Incubation of cells with high glucose (HG, 30 mM) markedly induced the oxidative stress of HGMCs, which were abolished by 5-aminoimidazole-4-carboxamide ribonucleoside, AMPK gene overexpression or BBR. Importantly, the effects induced by BBR were bypassed by AMPK siRNA transfection in HG-treated HGMCs. In animal studies, streptozotocin-induced hyperglycemia dramatically promoted glomerulosclerosis and impaired kidney function by increasing serum BUN, urinary protein excretion, and decreasing Ccr, as well as increased oxidative stress. Administration of BBR remarkably improved kidney function in wildtype mice but not in AMPK?2-deficient mice. We conclude that AMPK activation is required for BBR to improve kidney function in diabetic mice.
Related JoVE Video
Diffusion of Lexical Change in Social Media.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Computer-mediated communication is driving fundamental changes in the nature of written language. We investigate these changes by statistical analysis of a dataset comprising 107 million Twitter messages (authored by 2.7 million unique user accounts). Using a latent vector autoregressive model to aggregate across thousands of words, we identify high-level patterns in diffusion of linguistic change over the United States. Our model is robust to unpredictable changes in Twitter's sampling rate, and provides a probabilistic characterization of the relationship of macro-scale linguistic influence to a set of demographic and geographic predictors. The results of this analysis offer support for prior arguments that focus on geographical proximity and population size. However, demographic similarity - especially with regard to race - plays an even more central role, as cities with similar racial demographics are far more likely to share linguistic influence. Rather than moving towards a single unified "netspeak" dialect, language evolution in computer-mediated communication reproduces existing fault lines in spoken American English.
Related JoVE Video
A Poorly Differentiated Malignant Neoplasm Lacking Lung Markers Harbors an EML4-ALK Rearrangement and Responds to Crizotinib.
Case Rep Oncol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Suspected metastatic site lesions that are poorly differentiated present a diagnostic challenge when morphologic and immunohistochemical profiling cannot establish the primary tumor site. Here we present a patient diagnosed with both a malignant neoplasm in the lung and a right upper extremity (RUE) neoplasm of unclear histogenetic origin. Immunohistochemical staining performed on the latter specimen was inconclusive in determining the site of origin. Although the lung biopsy sample was insufficient for molecular testing, hybrid capture-based comprehensive genomic profiling (FoundationOne) identified an EML4-ALK rearrangement in the RUE lesion. Crizotinib treatment resulted in a major response in both the RUE and the lung lesions. This report illustrates the utility of comprehensive genomic profiling employed at the initial presentation of an unknown primary malignant neoplasm, which resulted in the front-line use of targeted therapy and a significant and sustained antitumor response.
Related JoVE Video
Effect of layer thickness and printing orientation on mechanical properties and dimensional accuracy of 3D printed porous samples for bone tissue engineering.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Powder-based inkjet 3D printing method is one of the most attractive solid free form techniques. It involves a sequential layering process through which 3D porous scaffolds can be directly produced from computer-generated models. 3D printed products' quality are controlled by the optimal build parameters. In this study, Calcium Sulfate based powders were used for porous scaffolds fabrication. The printed scaffolds of 0.8 mm pore size, with different layer thickness and printing orientation, were subjected to the depowdering step. The effects of four layer thicknesses and printing orientations, (parallel to X, Y and Z), on the physical and mechanical properties of printed scaffolds were investigated. It was observed that the compressive strength, toughness and Young's modulus of samples with 0.1125 and 0.125 mm layer thickness were more than others. Furthermore, the results of SEM and ?CT analyses showed that samples with 0.1125 mm layer thickness printed in X direction have more dimensional accuracy and significantly close to CAD software based designs with predefined pore size, porosity and pore interconnectivity.
Related JoVE Video
Durable Response to Crizotinib in a MET-Amplified, KRAS-Mutated Carcinoma of Unknown Primary.
Case Rep Oncol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Carcinoma of unknown primary (CUP) accounts for 3-5% of all adult solid tumors. An extensive search for the anatomic site of origin is often undertaken in an attempt to tailor systemic treatment, but the latter often has limited efficacy - especially in the setting of an initial treatment failure. Molecularly targeted therapy is an emerging approach that may offer greater efficacy and less toxicity but is most likely to be effective when pairing a tumor harboring a sensitizing genomic alteration with an agent directed at the altered gene product. We report a patient with a CUP harboring a MET amplification with a complete metabolic response to crizotinib despite also harboring a KRAS mutation.
Related JoVE Video
Nature and pattern of cricket injuries: the Asian Cricket Council Under-19, Elite Cup, 2013.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Cricket has over the years gained much popularity in Asia, thus the number of cricket players has also grown in tandem. However, cricket players are not as fortunate as other athletes as they do not always have a standard cricket infrastructure to practice; therefore, the injury prevalence is expected to be high. Unfortunately, very few studies have been conducted to investigate the nature and pattern of cricket injuries prevalent to cricketers in this region. Therefore, a prospective cohort injury surveillance study was conducted during the Asian Cricket Council (ACC) Under-19 Elite Cup held in June 2013 in order to gather more data on the type of injuries sustained by cricket players. Overall, 31 injuries occurred to 28 players throughout the tournament, of which 7 injuries happened during practice sessions. The overall injury incidence rate (IIR) was 292.0 per 10,000 player hours (95% CI 176.9-407.1) and 10.4 per 10,000 balls faced and 2.6 per 1000 overs bowled delivered during batting and bowling, respectively. Injuries to the lower limb (IIR: 146; 95% CI 1.8-98.2) were the most frequent, followed by injuries to the upper limb (97.3;95% CI 30.2-164.5) and to the trunk and back (IIR: 36.5;95% CI 0.0-77.7). Sprain/strains (IIR 109.5;95% CI 38.4-180.7) to muscle/tendon and joint/ligament were the most commonly reported nature of injury. This is the first study investigating injury incidence among the players of the ACC. It provides an overview of injuries sustained by elite players' under-19 years of age from 10 Asian countries. The overall IIR is similar to earlier studies conducted in well-established cricket playing nations.
Related JoVE Video
Gait biomechanics of individuals with transtibial amputation: effect of suspension system.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Prosthetic suspension system is an important component of lower limb prostheses. Suspension efficiency can be best evaluated during one of the vital activities of daily living, i.e. walking. A new magnetic prosthetic suspension system has been developed, but its effects on gait biomechanics have not been studied. This study aimed to explore the effect of suspension type on kinetic and kinematic gait parameters during level walking with the new suspension system as well as two other commonly used systems (the Seal-In and pin/lock). Thirteen persons with transtibial amputation participated in this study. A Vicon motion system (six cameras, two force platforms) was utilized to obtain gait kinetic and kinematic variables, as well as pistoning within the prosthetic socket. The gait deviation index was also calculated based on the kinematic data. The findings indicated significant difference in the pistoning values among the three suspension systems. The Seal-In system resulted in the least pistoning compared with the other two systems. Several kinetic and kinematic variables were also affected by the suspension type. The ground reaction force data showed that lower load was applied to the limb joints with the magnetic suspension system compared with the pin/lock suspension. The gait deviation index showed significant deviation from the normal with all the systems, but the systems did not differ significantly. Main significant effects of the suspension type were seen in the GRF (vertical and fore-aft), knee and ankle angles. The new magnetic suspension system showed comparable effects in the remaining kinetic and kinematic gait parameters to the other studied systems. This study may have implications on the selection of suspension systems for transtibial prostheses. Trial registration: Iranian Registry of Clinical Trials IRCT2013061813706N1.
Related JoVE Video

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.