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Find video protocols related to scientific articles indexed in Pubmed.
Piezoelectric coupling in a field-effect transistor with a nanohybrid channel of ZnO nanorods grown vertically on graphene.
Nanoscale
PUBLISHED: 11-06-2014
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Piezoelectric coupling phenomena in a graphene field-effect transistor (GFET) with a nano-hybrid channel of chemical-vapor-deposited Gr (CVD Gr) and vertically aligned ZnO nanorods (NRs) under mechanical pressurization were investigated. Transfer characteristics of the hybrid channel GFET clearly indicated that the piezoelectric effect of ZnO NRs under static or dynamic pressure modulated the channel conductivity (?) and caused a positive shift of 0.25% per kPa in the Dirac point. However, the GFET without ZnO NRs showed no change in either ? or the Dirac point. Analysis of the Dirac point shifts indicated transfer of electrons from the CVD Gr to ZnO NRs due to modulation of their interfacial barrier height under pressure. High responsiveness of the hybrid channel device with fast response and recovery times was evident in the time-dependent behavior at a small gate bias. In addition, the hybrid channel FET could be gated by mechanical pressurization only. Therefore, a piezoelectric-coupled hybrid channel GFET can be used as a pressure-sensing device with low power consumption and a fast response time. Hybridization of piezoelectric 1D nanomaterials with a 2D semiconducting channel in FETs enables a new design for future nanodevices.
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Risk Assessment of Volatile Organic Compounds Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) in Consumer Products.
J. Toxicol. Environ. Health Part A
PUBLISHED: 10-25-2014
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Exposure and risk assessment was performed by evaluating levels of volatile organic compounds (VOC) benzene, toluene, ethylbenzene, and xylene (BTEX) in 207 consumer products. The products were categorized into 30 different items, consisting of products of different brands. Samples were analyzed for BTEX by headspace-gas chromatography/mass spectrometry (headspace-GC/MS) with limit of detection (LOD) of 1 ppm. BTEX were detected in 59 consumer products from 18 item types. Benzene was detected in whiteout (ranging from not detected [ND] to 3170 ppm), glue (1486 ppm), oil-based ballpoint pens (47 ppm), and permanent (marking) pens (2 ppm). Toluene was detected in a leather cleaning product (6071 ppm), glue (5078 ppm), whiteout (1130 ppm), self-adhesive wallpaper (15-1012 ppm), shoe polish (806 ppm), permanent pen (609 ppm), wig adhesive (372 ppm), tapes (2-360 ppm), oil-based ballpoint pen (201 ppm), duplex wallpaper (12-52 ppm), shoes (27 ppm), and air freshener (13 ppm). High levels of ethylbenzene were detected in permanent pen (ND-345,065 ppm), shoe polish (ND-277,928 ppm), leather cleaner (42,223 ppm), whiteout (ND-2,770 ppm), and glue (ND-792 ppm). Xylene was detected in permanent pen (ND-285,132 ppm), shoe polish (ND-87,298 ppm), leather cleaner (12,266 ppm), glue (ND-3,124 ppm), and whiteout (ND-1,400 ppm). Exposure assessment showed that the exposure to ethylbenzene from permanent pens ranged from 0 to 3.11 mg/kg/d (men) and 0 to 3.75 mg/kg/d (women), while for xylene, the exposure ranges were 0-2.57 mg/kg/d and 0-3.1 mg/kg/d in men and women, respectively. The exposure of women to benzene from whiteout ranged from 0 to 0.00059 mg/kg/d. Hazard index (HI), defined as a ratio of exposure to reference dose (RfD), for ethylbenzene was 31.1 (3.11 mg/kg/d/0.1 mg/kg/d) and for xylene (2.57 mg/kg/d/0.2 mg/kg/d) was 12.85, exceeding 1 for both compounds. Cancer risk for benzene was calculated to be 3.2 × 10(-5) based on (0.00059 mg/kg/d × 0.055 mg/kg-d(-1), cancer potency factor), assuming that 100% of detected levels in some products such as permanent pens and whiteouts were exposed in a worst-case scenario. These data suggest that exposure to VOC via some consumer products exceeded the safe limits and needs to be reduced.
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The No-Observed-Adverse-Effect Level (NOAEL) of Baby Aloe Powder (BAP) for Nutraceutical Application Based Upon Toxicological Evaluation.
J. Toxicol. Environ. Health Part A
PUBLISHED: 10-25-2014
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Aloe has been used in versatile herbal medications and nutraceuticals throughout history. Aloe is widely considered to be generally safe for humans and used globally. The effectiveness and pharmacological properties of aloe are dependent upon when the plant is collected. However, little is known about the toxicology of whole-body aloe collected within less than 1 yr. Based upon widespread exposure to aloe, it is important to determine a daily intake level of this chemical to ensure its safety for humans. To determine the no-observed-adverse-effect level (NOAEL) of baby aloe powder (BAP) for clinical application, Sprague-Dawley (SD) rats were treated orally for 4 wk with 4 different concentrations: 0, 0.125, 0.5, and 2 g/kg body weight (bw). In this study, no significant or dose-dependent toxicological effects of BAP were observed in biochemical or hematological parameters, urinalysis, clinical signs, body weight, and food and water consumption. There were changes in some biomarkers in certain treated groups compared to controls; however, all values were within their reference ranges and not dose-dependent. Based on these results, the NOAEL of BAP was estimated to be greater than 2 g/kg bw in male and 2 g/kg bw in female SD rats. Collectively, these data suggest that BAP used in this study did not produce any marked subacute toxic effects up to a maximum concentration of 2 g/kg bw, and thus use in nutraceuticals and in pharmaceutical and cosmetic applications at a concentration of >2 g/kg is warranted.
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Intermittent Hypoxia-Induced Glucose Intolerance is Abolished by Alpha-Adrenergic Blockade or Adrenal Medullectomy.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 10-16-2014
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Background: Obstructive sleep apnea (OSA) causes intermittent hypoxia (IH) during sleep, and is associated with dysregulation of glucose metabolism. We developed a novel model of clinically realistic IH in mice to test the hypothesis that IH causes hyperglycemia, glucose intolerance, and insulin resistance via activation of the sympathetic nervous system (SNS). Methods: Mice were exposed to acute hypoxia of graded severity (21%, 14%, 10%, 7% O2) or to IH of graded frequency (oxygen desaturation index, ODI of 0, 15, 30, or 60, SpO2 nadir 80%) for 30 minutes to measure levels of glucose fatty acids, glycerol, insulin, and lactate. Glucose tolerance tests and insulin tolerance tests were then performed under each hypoxia condition. Next, we examined these outcomes in mice that were administered phentolamine (? adrenergic blockade), propranolol (? adrenergic blockade) or that underwent adrenal medullectomy before IH exposure. In all experiments, mice were maintained in a thermoneutral environment. Results: Sustained and intermittent hypoxia induced hyperglycemia, glucose intolerance, and insulin resistance in a dose dependent fashion. Only severe hypoxia (7% O2) increased lactate, and only frequent IH (ODI-60) increased plasma fatty acids. Phentolamine or adrenal medullectomy both prevented IH-induced hyperglycemia and glucose intolerance. IH inhibited glucose-stimulated insulin secretion, and phentolamine prevented the inhibition. Propranolol had no effect on glucose metabolism but abolished IH-induced lipolysis. IH-induced insulin resistance was not affected by any intervention. Conclusions: Acutely hypoxia causes hyperglycemia, glucose intolerance, and insulin resistance in a dose-dependent manner. During IH, circulating catecholamines act upon ?-adrenoreceptors to cause hyperglycemia and glucose intolerance.
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Ultra-Low-Dose Chest CT in Patients with Neutropenic Fever and Hematologic Malignancy: Image Quality and Its Diagnostic Performance.
Cancer Res Treat
PUBLISHED: 10-14-2014
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The aim of this study was to evaluate the image quality of ultra-low-dose computed tomography (ULDCT) and its diagnostic performance in making a specific diagnosis of pneumonia in febrile neutropenic patients with hematological malignancy.
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Epigenetic approaches to regeneration of bone and cartilage from stem cells.
Expert Opin Biol Ther
PUBLISHED: 10-07-2014
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Introduction: Embryonic stem cells (ESCs) or adult stem cells, especially mesenchymal stem cells (MSCs), have been intensively studied for skeletal tissue regeneration including bone and cartilage. Epigenetic mechanisms play essential roles in stem cell maintenance and differentiation. However, little is known about the epigenetic regulation of osteogenesis and chondrogenesis of stem cells. Areas covered: In this review, features of ESCs and adult stem cells, epigenetics and chromatin structure, as well as epigenetic mechanisms, such as chromatin remodeling, DNA methylation and histone modifications, polycomb group (PcG) proteins and microRNAs are described. Epigenetic researches of stem cell are introduced. Expert opinion: Epigenetic alterations of stem cell during the in vitro differentiation can be controlled for clinical applications. MSCs are effective resources for skeletal tissue regeneration in both undifferentiated and differentiated states. Understanding epigenetic signatures of MSC is crucial to maintain the stemness. In addition, investigation of epigenetic changes in the differentiation of MSCs is very important to develop methods or chemicals to promote efficient differentiation of MSCs. Inhibition of PcG protein enhancer of zeste (Ezh2) a chromatin modifier, could be a promising candidate to improve MSC differentiation by decreasing Ezh2-mediated H3K27me3.
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Carbon-, binder-, and precious metal-free cathodes for non-aqueous lithium-oxygen batteries: nanoflake-decorated nanoneedle oxide arrays.
ACS Appl Mater Interfaces
PUBLISHED: 10-03-2014
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Rechargeable lithium-oxygen (Li-O2) batteries have higher theoretical energy densities than today's lithium-ion batteries and are consequently considered to be an attractive energy storage technology to enable long-range electric vehicles. The main constituents comprising a cathode of a lithium-oxygen (Li-O2) battery, such as carbon and binders, suffer from irreversible decomposition, leading to significant performance degradation. Here, carbon- and binder-free cathodes based on nonprecious metal oxides are designed and fabricated for Li-O2 batteries. A novel structure of the oxide-only cathode having a high porosity and a large surface area is proposed that consists of numerous one-dimensional nanoneedle arrays decorated with thin nanoflakes. These oxide-only cathodes with the tailored architecture show high specific capacities and remarkably reduced charge potentials (in comparison with a carbon-only cathode) as well as excellent cyclability (250 cycles).
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Locally advanced rectal cancer: post-chemoradiotherapy ADC histogram analysis for predicting a complete response.
Acta Radiol
PUBLISHED: 10-02-2014
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The value of diffusion-weighted imaging (DWI) for reliable differentiation between pathologic complete response (pCR) and residual tumor is still unclear. Recently, a few studies reported that histogram analysis can be helpful to monitor the therapeutic response in various cancer research.
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A study of the effects of physical dermabrasion combined with chemical peeling in porcine skin.
J Cosmet Laser Ther
PUBLISHED: 09-27-2014
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Background: Many comparative studies of chemical peeling and dermabrasion have been reported. However, rare basic scientific data about the immediate effects after combined treatment with chemical peeling and dermabrasion have been confirmed. Objectives: The aim of this study is to evaluate the effect of the application of physical abrasion in combination with chemical peels. Materials and methods: Three pigs were treated with physical abrasion using a water jet device in combination with an ?-hydroxy acid solution, and the skin samples of the control received chemical peeling solution alone. The levels of growth factors and neuropeptides were measured with a multiplex immunoassay. Result: Skin treated with physical dermabrasion combined with chemical peeling showed prominent detachment and swelling of the stratum corneum (SC), and fluid collection in the hair follicles. The mean cell count of CD34 positive fibroblasts and mast cells, levels of epidermal growth factor, fibroblast growth factor-2, vascular endothelial growth factor, and neurotensin, were significantly increased in the tissue treated with physical abrasion combined with a chemical peeling agent, compared to the skin in the control. Conclusion: We concluded that physical dermabrasion combined with chemical peeling can be more effective than chemical peeling alone, for the approach through transfollicular routes.
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Aged Black Garlic Exerts Anti-Inflammatory Effects by Decreasing NO and Proinflammatory Cytokine Production with Less Cytoxicity in LPS-Stimulated RAW 264.7 Macrophages and LPS-Induced Septicemia Mice.
J Med Food
PUBLISHED: 09-19-2014
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Abstract In this study, the anti-inflammatory and antisepticemic activities of a water extract of aged black garlic (AGE), which is not pungent, were compared with those of raw garlic extract (RGE). The methyl thiazolyl tetrazolium (MTT) assay showed that AGE was not toxic up to 1000 ?g/mL and was at least four times less cytotoxic than RGE. AGE significantly suppressed the production of nitric oxide (NO), tumor-necrosis factor-? (TNF-?), and prostaglandin (PG)-E2 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Furthermore, the inhibitory effect of AGE on LPS-induced inflammation was confirmed by downregulation of inducible NO synthase and TNF-? mRNA expression, as well as cyclooxygenase-2 protein expression. The anti-inflammatory activities of AGE were similar to those of RGE at nontoxic concentrations up to 250 ?g/mL. Signal transduction pathway studies further indicated that both garlic extracts inhibited activation of mitogen-activated protein kinase and nuclear factor-?B induced by LPS stimulation. Treatment with both AGE and RGE in an in vivo experiment of LPS-induced endotoxemia significantly reduced the level of TNF-? and interleukin-6 in serum and completely protected against LPS-induced lethal shock in C57BL/6 mice. The results suggest that AGE is a more promising nutraceutical or medicinal agent to prevent or cure inflammation-related diseases for safety aspects compared with RGE.
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Inter- and intra-individual comparative study of two gadolinium-based agents: A pilot study.
Abdom Imaging
PUBLISHED: 09-17-2014
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The aim of the study was to evaluate the acute adverse events rate and enhancement properties of gadoterate meglumine (Dotarem(®)) and gadobenate dimeglumine (MultiHance(®)) in a small-scale controlled double-blinded study, using inter- and intra-individual comparisons.
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Radical prostatectomy versus external beam radiotherapy for localized prostate cancer : Comparison of treatment outcomes.
Strahlenther Onkol
PUBLISHED: 09-14-2014
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We retrospectively compared the treatment outcomes of localized prostate cancer between radical prostatectomy (RP) and external beam radiotherapy (EBRT).
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The effect of adrenal medullectomy on metabolic responses to chronic intermittent hypoxia.
Respir Physiol Neurobiol
PUBLISHED: 08-29-2014
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Obstructive sleep apnea causes intermittent hypoxia (IH) and is associated with insulin resistance and type 2 diabetes. IH increases plasma catecholamine levels, which may increase insulin resistance and suppress insulin secretion. The objective of this study was to determine if adrenal medullectomy (MED) prevents metabolic dysfunction in IH. MED or sham surgery was performed in 60 male C57BL/6J mice, which were then exposed to IH or control conditions (intermittent air) for 6 weeks. IH increased plasma epinephrine and norepinephrine levels, increased fasting blood glucose and lowered basal and glucose-stimulated insulin secretion. MED decreased baseline epinephrine and prevented the IH induced increase in epinephrine, whereas the norepinephrine response remained intact. MED improved glucose tolerance in mice exposed to IH, attenuated the impairment in basal and glucose-stimulated insulin secretion, but did not prevent IH-induced fasting hyperglycemia or insulin resistance. We conclude that the epinephrine release from the adrenal medulla during IH suppresses insulin secretion causing hyperglycemia.
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Nanostructural change of human melanocytes stimulated with ?-melanocyte stimulating hormone observed by atomic force microscopy.
Scanning
PUBLISHED: 08-29-2014
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It is well known that ?-melanocyte stimulating hormone (?-MSH) induces melanization, but structural changes of melanocytes after ?-MSH exposure are not well known. This study investigated the serial morphologic changes of human cultured melanocytes after stimulation with ?-MSH using atomic force microscopy (AFM). Cultured human melanocytes were treated with ?-MSH for 7 days. Contact mode AFM images were obtained using a NANOstation II and fixed melanocytes were scanned in PBS solution at a resolution of 512?×?512 pixels, at a scan speed of 0.4?line/s. The surface roughness and pore-like structures of the melanocytes were measured from topographic images using the Scanning Probe Imaging Processor. The surface roughness of cell body did not change significantly over time. All three roughness parameters (Sa, Sq, Sz) inside the pore-like structures on the dendrites increased significantly. The number of pore-like structures increased and the length and the breadth of pore-like structures also increased gradually. Pore-like structures changed statistically significantly in response to ?-MSH stimulation. Further study will be needed to clarify whether the nature of pore-like structures is related to movement of melanosomes. SCANNING 9999:XX-XX, 2014. © 2014 Wiley Periodicals, Inc.
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UV-B radiation-induced oxidative stress and p38 signaling pathway involvement in the benthic copepod Tigriopus japonicus.
Comp. Biochem. Physiol. C Toxicol. Pharmacol.
PUBLISHED: 08-23-2014
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Ultraviolet B (UV-B) radiation presents an environmental hazard to aquatic organisms. To understand the molecular responses of the intertidal copepod Tigriopus japonicus to UV-B radiation, we measured the acute toxicity response to 96h of UV-B radiation, and we also assessed the intracellular reactive oxygen species (ROS) levels, glutathione (GSH) content, and antioxidant enzyme (GST, GR, GPx, and SOD) activities after 24h of exposure to UV-B with LD50 and half LD50 values. Also, expression patterns of p53 and hsp gene families with phosphorylation of p38 MAPK were investigated in UV-B-exposed copepods. We found that the ROS level, GSH content, and antioxidant enzyme activity levels were increased with the transcriptional upregulation of antioxidant-related genes, indicating that UV-B induces oxidative stress by generating ROS and stimulating antioxidant enzymatic activity as a defense mechanism. Additionally, we found that p53 expression was significantly increased after UV-B irradiation due to increases in the phosphorylation of the stress-responsive p38 MAPK, indicating that UV-B may be responsible for inducing DNA damage in T. japonicus. Of the hsp family genes, transcriptional levels of hsp20, hsp20.7, hsp70, and hsp90 were elevated in response to a low dose of UV-B radiation (9kJm(-2)), suggesting that these hsp genes may be involved in cellular protection against UV-B radiation. In this paper, we performed a pathway-oriented mechanistic analysis in response to UV-B radiation, and this analysis provides a better understanding of the effects of UV-B in the intertidal benthic copepod T. japonicus.
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Randomized, controlled trial of qigong for treatment of prehypertension and mild essential hypertension.
Altern Ther Health Med
PUBLISHED: 08-21-2014
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Hypertension treatments include sodium restriction, pharmacological management, and lifestyle modifications. Although many cases of hypertension can be controlled by medication, individuals may experience side effects or incur out-of-pocket expenses, and some may not comply with the treatment regimen. Although some previous studies have shown a favorable effect for qigong on hypertension, well-designed, rigorous trials evaluating the effect of qigong on hypertension are scarce.
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Quantification of 4-methylimidazole in carbonated beverages by ultra-performance liquid chromatography-tandem mass spectrometry.
Arch. Pharm. Res.
PUBLISHED: 08-11-2014
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2- and 4-methylimidazoles (2-MI and 4-MI) are undesired byproducts produced during the manufacture of caramel color used to darken food products such as carbonated beverages. The Office of Environmental Health Hazard Assessment in California listed 4-MI as carcinogen in January 2011 with a proposed no significant risk level at 29 ?g per person per day. Thus, a quantitative analytical measurement for 2-MI and 4-MI is desired for reliable risk assessments for exposure. An ultra-performance liquid chromatography (UPLC) coupled tandem mass spectrometric (MS/MS) method was developed for the quantification of 4-MI in beverage samples. Chromatographic separation of 2-MI and 4-MI were achieved by using a PFP reversed-phase column and a stepwise gradient of methanol and distilled water containing 0.1 % formic acid. Identification and quantification of 2-MI and 4-MI were performed using electrospray ionization-tandem mass monitoring the precursor to product ion transitions for 2-MI at m/z 83.1 ? 42.2 and 4-MI at m/z 83.1 ? 56.1 with melamine at m/z 127.1 ? 85.1 as the internal standard. The performance of the method was evaluated against validation parameters such as specificity, carryover, linearity and calibration, correlation of determination (r(2)), detection limit, precision, accuracy, and recovery. Calibration curves at 10-400 ng/mL were constructed by plotting concentration versus peak-area ratio (analyte/internal standard) and fitting the data with a weighted 1/x. The accuracy of the assay ranged from 93.58 to 110.53 % for all analytes. Intra-assay precision for 2-MI and 4-MI were below 7.28 (relative standard deviation/RSD %) at QC samples. Here we present a new and improved method using UPLC-MS/MS to significantly simplify sample preparation and decrease chromatographic run time. This method allows accurate and reproducible quantification of 4-MI in carbonated beverages as low as sub ng/mL (ppb) levels.
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Carotid body denervation prevents fasting hyperglycemia during chronic intermittent hypoxia.
J. Appl. Physiol.
PUBLISHED: 08-07-2014
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Obstructive sleep apnea causes chronic intermittent hypoxia (IH) and is associated with impaired glucose metabolism, but mechanisms are unknown. Carotid bodies orchestrate physiological responses to hypoxemia by activating the sympathetic nervous system. Therefore, we hypothesized that carotid body denervation would abolish glucose intolerance and insulin resistance induced by chronic IH. Male C57BL/6J mice underwent carotid sinus nerve dissection (CSND) or sham surgery and then were exposed to IH or intermittent air (IA) for 4 or 6 wk. Hypoxia was administered by decreasing a fraction of inspired oxygen from 20.9% to 6.5% once per minute, during the 12-h light phase (9 a.m.-9 p.m.). As expected, denervated mice exhibited blunted hypoxic ventilatory responses. In sham-operated mice, IH increased fasting blood glucose, baseline hepatic glucose output (HGO), and expression of a rate-liming hepatic enzyme of gluconeogenesis phosphoenolpyruvate carboxykinase (PEPCK), whereas the whole body glucose flux during hyperinsulinemic euglycemic clamp was not changed. IH did not affect glucose tolerance after adjustment for fasting hyperglycemia in the intraperitoneal glucose tolerance test. CSND prevented IH-induced fasting hyperglycemia and increases in baseline HGO and liver PEPCK expression. CSND trended to augment the insulin-stimulated glucose flux and enhanced liver Akt phosphorylation at both hypoxic and normoxic conditions. IH increased serum epinephrine levels and liver sympathetic innervation, and both increases were abolished by CSND. We conclude that chronic IH induces fasting hyperglycemia increasing baseline HGO via the CSN sympathetic output from carotid body chemoreceptors, but does not significantly impair whole body insulin sensitivity.
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An integrated view of gamma radiation effects on marine fauna: from molecules to ecosystems.
Environ Sci Pollut Res Int
PUBLISHED: 08-04-2014
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Accidental release of nuclides into the ocean is causing health risks to marine organisms and humans. All life forms are susceptible to gamma radiation with a high variation, depending on various physical factors such as dose, mode, and time of exposure and various biological factors such as species, vitality, age, and gender. Differences in sensitivity of gamma radiation are also associated with different efficiencies of mechanisms related to protection and repair systems. Gamma radiation may also affect various other integration levels: from gene, protein, cells and organs, population, and communities, disturbing the energy flow of food webs that will ultimately affect the structure and functioning of ecosystems. Depending on exposure levels, gamma radiation induces damages on growth and reproduction in various organisms such as zooplankton, benthos, and fish in aquatic ecosystems. In this paper, harmful effects of gamma-irradiated aquatic organisms are described and the potential of marine copepods in assessing the risk of gamma radiation is discussed with respect to physiological adverse effects that even affect the ecosystem level.
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Treatment factors affecting breast cancer-related lymphedema after systemic chemotherapy and radiotherapy in stage II/III breast cancer patients.
Breast Cancer Res. Treat.
PUBLISHED: 08-04-2014
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We evaluated whether the sequence or regimen of systemic chemotherapy could be a risk factor for breast cancer-related lymphedema (LE). We retrospectively analyzed 848 patients with stage II/III breast cancer who underwent curative surgery with adequate systemic therapy from 2004 to 2009. Adjuvant chemotherapy (ACT) was performed in 552 patients (65.1 %) and neoadjuvant chemotherapy (NAC) in 296 (34.9 %). We evaluated the incidence of LE based on clinicopathological factors and treatments. At a median follow-up of 5.1 years, 358 patients (42.2 %) had experienced LE and 243 (28.7 %) had retained (persistent LE) [120/552 (21.7 %) with ACT vs. 123/296 (41.6 %) with NAC; P < 0.001]. The incidence of LE in patients with taxane was greater than in those without taxane [233/704 (33.1 %) vs. 10/144 (6.9 %); P < 0.001]. Multivariate analysis showed that NAC [hazard ratio (HR), 1.63 in LE event; P < 0.001; HR, 1.39 in persistent LE; P = 0.02] and RT including supraclavicular area (SCRT) (HR 1.55; P = 0.02; HR 1.93; P = 0.006), number of dissected axillary lymph nodes (N-ALNs) >10 (HR, 1.37; P = 0.01; HR, 1.71; P = 0.001), advanced stage (HR, 1.31; P = 0.03; HR, 1.60; P = 0.002), and taxane (HR, 1.69; P = 0.03; HR, 2.07; P = 0.04) were independent risk factors for the LE occurrence. In addition to advanced stage, N-ALNs and SCRT, NAC, and taxane were shown to increase the risk of LE, which could help clinicians identify patients at risk for LE.
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Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.
Neuropeptides
PUBLISHED: 08-01-2014
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Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA.
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Production of 5,8-dihydroxy-9(Z)-octadecenoic acid from oleic acid by whole recombinant cells of Aspergillus nidulans expressing diol synthase.
Biotechnol. Lett.
PUBLISHED: 07-07-2014
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The optimal conditions for the production of 5,8-dihydroxy-9(Z)-octadecenoic acid (5,8-diHOME) from oleic acid by whole recombinant Escherichia coli cells expressing diol synthase from Aspergillus nidulans were 40 °C, pH 7.5, 10 % (v/v) dimethyl sulfoxide, 35 g cells l(-1), and 12 g oleic acid l(-1) at 250 rpm in a 250 ml baffled flask. Under these conditions, whole recombinant cells produced 5.2 g 5,8-diHOME l(-1) together with 1 g l(-1) of the intermediate 8-hydroperoxy-9(Z)-octadecenoic acid (8-HPOME) after 60 min. This corresponded to a conversion yield of 43 % (w/w), a volumetric productivity of 5.2 g l(-1 )h(-1), and a specific productivity of 148 mg g cells(-1 )h(-1). This is the first report of the biotechnological production of 5,8-diHOME from oleic acid.
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An ice-templated, pH-tunable self-assembly route to hierarchically porous graphene nanoscroll networks.
Nanoscale
PUBLISHED: 07-07-2014
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Porous graphene nanostructures are of great interest for applications in catalysis and energy storage. However, the fabrication of three-dimensional (3D) macroporous graphene nanostructures with controlled morphology, porosity and surface area still presents significant challenges. Here we introduce an ice-templated self-assembly approach for the integration of two-dimensional graphene nanosheets into hierarchically porous graphene nanoscroll networks, where the morphology of porous structures can be easily controlled by varying the pH conditions during the ice-templated self-assembly process. We show that freeze-casting of reduced graphene oxide (rGO) solution results in the formation of 3D porous graphene microfoam below pH 8 and hierarchically porous graphene nanoscroll networks at pH 10. In addition, we demonstrate that graphene nanoscroll networks show promising electrocatalytic activity for the oxygen reduction reaction (ORR).
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Functional characterization of P-glycoprotein in the intertidal copepod Tigriopus japonicus and its potential role in remediating metal pollution.
Aquat. Toxicol.
PUBLISHED: 06-27-2014
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The intertidal copepod Tigriopus japonicus has been widely used in aquatic toxicity testing for diverse environmental pollutants including metals. Despite relatively well-characterized in vivo physiological modulations in response to aquatic pollutants, the molecular mechanisms due to toxicity and detoxification are still unclear. To better understand the mechanisms of metal transport and further detoxification, T. japonicus P-glycoprotein (TJ-P-gp) with conserved motifs/domains was cloned and measured for protein activity against the transcript and protein expression profiles in response to metal exposure. Specifically, we characterized the preliminary efflux activity and membrane topology of TJ-P-gp protein that supports a transport function for chemicals. To uncover whether the efflux activity of TJ-P-gp protein would be modulated by metal treatment, copepods were exposed to three metals (Cd, Cu, and Zn), and were observed for both dose- and time-dependency on the efflux activity of TJ-P-gp protein with or without 10?M of P-gp-specific inhibitors verapamil and zosuquidar (LY335979) for 24h over a wide range of metal concentrations. In particular, treatment with zosuquidar induced metal accumulation in the inner body of T. japonicus. In addition, three metals significantly induced the transporting activity of TJ-P-gp in a concentration-dependent manner in both transcript and protein levels within 24h. Together these data indicate that T. japonicus has a conserved P-gp-mediated metal defense system through the induction of transcriptional up-regulation of TJ-P-gp gene and TJ-P-gp protein activity. This finding provides further understanding of the molecular defense mechanisms involved in P-glycoprotein-mediated metal detoxification in copepods.
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Modulated expression and enzymatic activity of the monogonont rotifer Brachionus koreanus Cu/Zn- and Mn-superoxide dismutase (SOD) in response to environmental biocides.
Chemosphere
PUBLISHED: 06-26-2014
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Superoxide dismutases (SODs) are important antioxidant enzymes whose expression levels are often used as biomarkers for oxidative stress. To investigate the biomarker potential of the monogonont rotifer Brachionus koreanus SOD genes, the full-length Cu/Zn-SOD (Bk-Cu/Zn-SOD) and Mn-SOD (Bk-Mn-SOD) genes were cloned from genomic DNA and characterized. All amino acid residues involved in the formation of tertiary structure and metal binding in Bk-Cu/Zn-SOD and Bk-Mn-SOD were highly conserved across species. Phylogenetic analysis revealed that Bk-Mn-SOD, in particular, was closely clustered with mitochondrial Mn-SOD. Transcript analysis after exposure to six different biocides (alachlor, chlorpyrifos, dimethoate, endosulfan, lindane, and molinate) revealed that the transcriptional level of Bk-Cu/Zn-SOD was significantly increased in a dose-dependent manner. In contrast, the level of Bk-Mn-SOD transcript was significantly increased compared with control cells in response to chlorpyrifos, endosulfan, and molinate at their no observed effect concentrations (NOECs). However, exposure to alachlor, chlorpyrifos, and molinate significantly reduced the enzymatic activity of total SOD protein, while a decreased pattern was observed in all biocide treatments. Taken together, these results indicate that exposure to waterborne environmental biocides induces the transcription of Bk-Cu/Zn-SOD and Bk-Mn-SOD, but inhibits the enzymatic activity of Bk-SODs. These results contribute to our understanding of the modes of action of oxidative stress-mediating biocides on rotifer.
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Central emboli rather than saddle emboli predict adverse outcomes in patients with acute pulmonary embolism.
Thromb. Res.
PUBLISHED: 06-19-2014
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In patients with acute pulmonary embolism (PE), the prognostic implications of saddle or central emboli, as observed on computed tomography (CT), remain to be established. The aim of the present study was to assess whether the presence of saddle and central emboli could be used to predict clinical outcomes in patients with PE.
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Influence of boost radiotherapy in patients with ductal carcinoma in situ breast cancer: a multicenter, retrospective study in Korea (KROG 11-04).
Breast Cancer Res. Treat.
PUBLISHED: 05-30-2014
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To estimate the effect of boost radiotherapy on local recurrence-free survival (LRFS) in patients with ductal carcinoma in situ (DCIS) breast cancer. We included patients from nine institutions who met the following criteria: having Tis, age 18 years or older, having breast conserving surgery (BCS) and radiotherapy within 12 weeks after surgery. From 1995 through 2006, 728 patients were analyzed retrospectively by the Korean Radiation Oncology Group. All patients received whole-breast radiation therapy (WBRT) after BCS. 232 patients (31.9 %) also received boost radiation therapy (RT) (median 10 Gy). After median follow-up of 82 months, 5-year LRFS was 98.4 % and 10-year LRFS was 95.8 % for all patients. There was no statistically significant difference of LRFS between the boost and no-boost groups. Nineteen (2.6 %) patients had ipsilateral breast recurrences, including 12 of invasive recurrence and 7 DCIS. The presence of the HER2 receptor was associated with more invasive recurrences. Nine (1.2 %) patients developed contralateral breast cancer, including six invasive breast cancer and three DCIS. In the multivariate analysis, only the margin status was a significant prognostic factor for LRFS. Boost RT was not associated with further improvement of local control in DCIS after BCS and WBRT. HER2 receptor-positive patients may need further treatment with the anti-HER2 agents.
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Grb2-associated binder-1 is required for neuregulin-1-induced peripheral nerve myelination.
J. Neurosci.
PUBLISHED: 05-30-2014
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Grb2-associated binders (Gabs) are scaffolding proteins implicated in cell signaling via receptor tyrosine kinases including neuregulin-1(NRG1)-ErbB receptor signaling, which is essential for peripheral nerve myelination. Here, we show that the conditional removal of Gab1 from Schwann cells resulted in hypomyelination and abnormal development of Remak bundles. In contrast, hypomyelination was not observed in conventional Gab2 knock-out mice. Tyrosine phosphorylation of Gab1, but not Gab2, in sciatic nerves was upregulated during the myelination period and was found to be suppressed in NRG1-type III(+/-) mice, which display a hypomyelinated phenotype similar to that observed in Gab1 knock-out mice. Gab1 knock-out and NRG1-type III(+/-) mice both exhibited reduced extracellular signal-regulated kinase activity in myelinating nerves. In addition, Krox20, a transcription factor that is critical for myelination, has been identified as a target of the NRG1-Gab1 pathway during the myelination process. Our findings suggest that Gab1 is an essential component of NRG1-type III signaling during peripheral nerve development.
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Characterization of ?-xylosidase from Thermoanaerobacterium thermosaccharolyticum and its application to the production of ginsenosides Rg1 and Rh 1 from notoginsenosides R 1 and R 2.
Biotechnol. Lett.
PUBLISHED: 05-19-2014
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?-Xylosidase from Thermoanaerobacterium thermosaccharolyticum was purified by His-trap affinity chromatography giving a specific activity of 5.15 U mg(-1). From gel-filtration chromatography, the purified enzyme was a tetramer with a total molecular mass of 245 kDa. Maximal enzyme activity using o-nitrophenyl(NP)-?-D-xylopyranoside was at pH 6.5 and 60 °C, with a half-life of 50 h. The enzyme had highest activity for oNP-?-D-xylopyranoside among aryl-glycosides, and was only active for notoginsenosides R1 and R2 amongst various ginsenosides. ?-Xylosidase completely converted 2 g notoginsenosides R1 and R2 l(-1) to 1.69 g ginsenoside Rg1 l(-1) and 1.63 g ginsenoside Rh1 l(-1) in 4 and 18 h, respectively, with molar conversion yields of 100 % and specific productivities of 0.21 and 0.05 g g-enzyme(-1) h(-1), respectively. To our knowledge, this is the first report on the enzymatic production of ginsenosides Rg1 and Rh1 from notoginsenosides R1 and R2.
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Clinical relevance of bronchial anthracofibrosis in patients with chronic obstructive pulmonary disease exacerbation.
Tuberc Respir Dis (Seoul)
PUBLISHED: 04-27-2014
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Bronchial anthracofibrosis (BAF), which is associated with exposure to biomass smoke in inefficiently ventilated indoor areas, can take the form of obstructive lung disease. Patients with BAF can mimic or present with an exacerbation of chronic obstructive pulmonary disease (COPD). The purpose of the current study was to investigate the prevalence of BAF in Korean patients with COPD exacerbation as well as to examine the clinical features of these patients in order to determine its clinical relevance.
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Synthesis of functional ZnO nanowall networks using simple solution etching.
J Nanosci Nanotechnol
PUBLISHED: 04-25-2014
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We report the synthesis of high quality single crystalline ZnO nanowall networks (NNs) using ammonia solution etching of a ZnO nanowire-nanowall heterojunction (NNH) structure. Synchrotron X-ray diffraction revealed that the full-width-at-half-maximum of the ZnO (0002) peak in the ZnO NN sample was much narrower than that of the ZnO NNH sample. Temperature-dependent photoluminescence (PL) measurements revealed more intense and narrower bound exciton peak emission in the NN sample compared to that in the NNH sample. Moreover, the clear observation of free exciton emission in the PL spectrum of the NN sample, even at temperatures as low as 30 K, suggested incorporation of a small number of impurities into the NN sample. In addition, I-V characteristics confirm the higher conductivity of the ZnO NNs as compared to those of the NNH structures, indicating that the NN sample had a superior crystalline property than NNH sample.
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Mitogen Activated Protein Kinase Family Proteins and c-jun Signaling in Injury-induced Schwann Cell Plasticity.
Exp Neurobiol
PUBLISHED: 04-23-2014
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Schwann cells (SCs) in the peripheral nerves myelinate axons during postnatal development to allow saltatory conduction of nerve impulses. Well-organized structures of myelin sheathes are maintained throughout life unless nerves are insulted. After peripheral nerve injury, unidentified signals from injured nerves drive SC dedifferentiation into an immature state. Dedifferentiated SCs participate in axonal regeneration by producing neurotrophic factors and removing degenerating nerve debris. In this review, we focus on the role of mitogen activated protein kinase family proteins (MAP kinases) in SC dedifferentiation. In addition, we will highlight neuregulin 1 and the transcription factor c-jun as upstream and downstream signals for MAP kinases in SC responses to nerve injury.
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A quasi-solid-state rechargeable lithium-oxygen battery based on a gel polymer electrolyte with an ionic liquid.
Chem. Commun. (Camb.)
PUBLISHED: 04-10-2014
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A quasi-solid-state lithium-oxygen battery constructed using a gel polymer electrolyte with an ionic liquid is proposed. The battery architecture incorporates a design feature that can be easily scaled up in size for use in large systems. The feasibility study demonstrates that the battery operates successfully for repeated discharge-charge cycles.
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Temporal changes in TBT pollution in water, sediment, and oyster from Jinhae Bay after the total ban in South Korea.
Mar. Pollut. Bull.
PUBLISHED: 04-08-2014
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Temporal change in tributyltin (TBT) levels in Jinhae Bay, which has various TBT sources, was investigated in water, sediments, and oysters from 2003 to 2013 after its total ban in South Korea. The seawater TBT levels decreased over 500-fold from 1995/97 to 2008/09. The oyster TBT levels were about fourfold lower in 2012/13 than in 1995/97. However, the sediment TBT levels did not significantly change, even 10 years after the partial TBT ban on small ships and 7 years after the total TBT ban on all oceangoing vessels in Korea. The total ban of TBT use effectively reduced water and oyster TBT levels in Jinhae Bay, but TBT levels in water, oysters, and sediment remained above the global environmental quality standards established to protect marine organisms.
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Comparison of sodium content of workplace and homemade meals through chemical analysis and salinity measurements.
Nutr Res Pract
PUBLISHED: 04-02-2014
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Most Koreans consume nearly 70-80% of the total sodium through their dishes. The use of a salinometer to measure salinity is recommended to help individuals control their sodium intake. The purpose of this study was to compare sodium content through chemical analysis and salinity measurement in foods served by industry foodservice operations and homemade meals.
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Dose- and time-dependent expression of aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) in PCB-, B[a]P-, and TBT-exposed intertidal copepod Tigriopus japonicus.
Chemosphere
PUBLISHED: 03-26-2014
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The aryl hydrocarbon receptor (AhR) and aryl hydrocarbon nuclear translocator (ARNT) genes from the copepod Tigriopus japonicus (Tj) were cloned to examine their potential functions in the invertebrate putative AhR-CYP signaling pathway. The amino acid sequences encoded by the Tj-AhR and Tj-ARNT genes showed high similarity to homologs of Daphnia and Drosophila, ranging from 68% and 70% similarity for the AhR genes to 56% for the ARNT genes. To determine whether Tj-AhR and Tj-ARNT are modulated by environmental pollutants, transcriptional expression of Tj-AhR and Tj-ARNT was analyzed in response to exposure to five concentrations of polychlorinated biphenyl (PCB 126) (control, 10, 50, 100, 500?gL(-1)), benzo[a]pyrene (B[a]P) (control, 5, 10, 50, 100?gL(-1)), and tributyltin (TBT) (control, 1, 5, 10, 20?gL(-1)) 24h after exposure. A time-course experiment (0, 3, 6, 12, 24h) was performed to analyze mRNA expression patterns after exposure to PCB, B[a]P, and TBT. T. japonicus exhibited dose-dependent and time-dependent upregulation of Tj-AhR and Tj-ARNT in response to pollutant exposure, and the degree of expression was dependent on the pollutant, suggesting that pollutants such as PCB, B[a]P, and TBT modulate expression of Tj-AhR and Tj-ARNT genes in the putative AhR-CYP signaling pathway.
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Effect of desipramine and citalopram treatment on forced swimming test-induced changes in cocaine- and amphetamine-regulated transcript (CART) immunoreactivity in mice.
Neurochem. Res.
PUBLISHED: 03-22-2014
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Recent study demonstrates antidepressant-like effect of cocaine- and amphetamine-regulated transcript (CART) in the forced swimming test (FST), but less is known about whether antidepressant treatments alter levels of CART immunoreactivity (CART-IR) in the FST. To explore this possibility, we assessed the treatment effects of desipramine and citalopram, which inhibit the reuptake of norepinephrine and serotonin into the presynaptic terminals, respectively, on changes in levels of CART-IR before and after the test swim in mouse brain. Levels of CART-IR in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), and hypothalamic paraventricular nucleus (PVN) were significantly increased before the test swim by desipramine and citalopram treatments. This increase in CART-IR in the AcbSh, dBNST, and PVN before the test swim remained elevated by desipramine treatment after the test swim, but this increase in these brain areas returned to near control levels after test swim by citalopram treatment. Citalopram, but not desipramine, treatment increased levels of CART-IR in the central nucleus of the amygdala (CeA) and the locus ceruleus (LC) before the test swim, and this increase was returned to control levels after the test swim in the CeA, but not in the LC. These results suggest common and distinct regulation of CART by desipramine and citalopram treatments in the FST and raise the possibility that CART in the AcbSh, dBNST, and CeA may be involved in antidepressant-like effect in the FST.
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Subcentimeter lung nodules stable for 2 years at LDCT: long-term follow-up using volumetry.
Respirology
PUBLISHED: 03-20-2014
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Subcentimeter nodules without change in size during long-term follow-up period (for minimum 2 years) are assumed as benign lesions. However, the 2-year stability rule has not been fully verified so far and is still questionable. Thus, we aimed to retrospectively investigate long-term follow-up results for 2-year stable subcentimeter nodules at screening low-dose computed tomography (LDCT).
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Effect of acute and chronic electroconvulsive shock on 5-hydroxytrypamine 6 receptor immunoreactivity in rat hippocampus.
Exp Neurobiol
PUBLISHED: 03-18-2014
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Electroconvulsive shock (ECS) induces not only an antidepressant effect but also adverse effects such as amnesia. One potential mechanism underlying both the antidepressant and amnesia effect of ECS may involve the regulation of serotonin (5-hydroxytryptamine) 6 (5-HT6) receptor, but less is known about the effects of acute ECS on the changes in 5-HT6 receptor expression in the hippocampus. In addition, as regulation of 5-HT receptor expression is influenced by the number of ECS treatment and by interval between ECS treatment and sacrifice, it is probable that magnitude and time-dependent changes in 5-HT6 receptor expression could be influenced by repeated ECS exposure. To explore this possibility, we observed and compared the changes of 5-HT6 receptor immunoreactivity (5-HT6 IR) in rat hippocampus at 1, 8, 24, or 72 h after the treatment with either a single ECS (acute ECS) or daily ECS for 10 days (chronic ECS). We found that acute ECS increased 5-HT6 IR in the CA1, CA3, and granule cell layer of hippocampus, reaching peak levels at 8 h and returning to basal levels 72 h later. The magnitude and time-dependent changes in 5-HT6 IR observed after acute ECS were not affected by chronic ECS. These results demonstrate that both acute and chronic ECS transiently increase the 5-HT6 IR in rat hippocampus, and suggest that the magnitude and time-dependent changes in 5-HT6 IR in the hippocampus appear not to be influenced by repeated ECS treatment.
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Hydrophobic sponge structure-based triboelectric nanogenerator.
Adv. Mater. Weinheim
PUBLISHED: 03-16-2014
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Hydrophobic sponge structure-based triboelectric nanogenerators using an inverse opal structured film for sustainable energy harvesting over a wide range of humid atmosphere have been successfully demonstrated. The output voltage and current density reach a record value of 130 V and 0.10 mA cm(-2) , respectively, giving over 10-fold power enhancement, compared with the flat film-based triboelectric nanogenerator.
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Effects of UV radiation on hatching, lipid peroxidation, and fatty acid composition in the copepod Paracyclopina nana.
Comp. Biochem. Physiol. C Toxicol. Pharmacol.
PUBLISHED: 03-12-2014
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To evaluate the effects of UV radiation on the reproductive physiology and macromolecules in marine zooplankton, several doses of UV radiation were used to treat the copepod Paracyclopina nana, and we analyzed in vivo endpoints of their life cycle such as mortality and reproductive parameters with in vitro biochemical biomarkers such as reactive oxygen species (ROS), the modulated enzyme activity of glutathione S-transferase (GST) and superoxide dismutase (SOD), and the production of a byproduct of peroxidation (e.g. malonedialdehyde, MDA). After UV radiation, the survival rate of P. nana was significantly reduced. Also, egg sac damage and a reduction in the hatching rate of offspring were observed in UV-irradiated ovigerous females. According to the assessed biochemical parameters, we found dose-dependent increases in ROS levels and high levels of the lipid peroxidation decomposition product by 2 kJ m(-2), implying that P. nana was under off-balanced status by oxidative stress-mediated cellular damage. Antioxidant enzyme activities of GST and SOD increased over different doses of UV radiation. To measure UV-induced lipid peroxidation, we found a slight reduction in the composition of essential fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These findings indicate that UV radiation can induce oxidative stress-triggered lipid peroxidation with modulation of antioxidant enzyme activity, leading to a significant effect on mortality and reproductive physiology (e.g. fecundity). These results demonstrate the involvement of UV radiation on essential fatty acids and its susceptibility to UV radiation in the copepod P. nana compared to other species.
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Characterization of a F280N variant of L-arabinose isomerase from Geobacillus thermodenitrificans identified as a D-galactose isomerase.
Appl. Microbiol. Biotechnol.
PUBLISHED: 03-04-2014
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The double-site variant (C450S-N475K) L-arabinose isomerase (L-AI) from Geobacillus thermodenitrificans catalyzes the isomerization of D-galactose to D-tagatose, a functional sweetener. Using a substrate-docking homology model, the residues near to D-galactose O6 were identified as Met186, Phe280, and Ile371. Several variants obtained by site-directed mutagenesis of these three residues were analyzed, and a triple-site (F280N) variant enzyme exhibited the highest activity for D-galactose isomerization. The k cat/K m of the triple-site variant enzyme for D-galactose was 2.1-fold higher than for L-arabinose, whereas the k cat/K m of the double-site variant enzyme for L-arabinose was 43.9-fold higher than for D-galactose. These results suggest that the triple-site variant enzyme is a D-galactose isomerase. The conversion rate of D-galactose to D-tagatose by the triple-site variant enzyme was approximately 3-fold higher than that of the double-site variant enzyme for 30 min. However, the conversion yields of L-arabinose to L-ribulose by the triple-site and double-site variant enzymes were 10.6 and 16.0 % after 20 min, respectively. The triple-site variant enzyme exhibited increased specific activity, turnover number, catalytic efficiency, and conversion rate for D-galactose isomerization compared to the double-site variant enzyme. Therefore, the amino acid at position 280 determines the substrate specificity for D-galactose and L-arabinose, and the triple-site variant enzyme has the potential to produce D-tagatose on an industrial scale.
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Spatial variability in chromophoric dissolved organic matter for an artificial coastal lake (Shiwha) and the upstream catchments at two different seasons.
Environ Sci Pollut Res Int
PUBLISHED: 02-25-2014
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Selected water quality parameters and spectroscopic characteristics of dissolved organic matter (DOM) were examined during two different seasons for an artificial coastal lake (Shiwha Lake in South Korea), which are affected by seawater exchange due to the operation of a tidal power plant and external organic loadings from the upstream catchments. The coastal lake exhibited much lower concentrations of organic matter and nutrients than the upstream sources. The spectroscopic properties of the lake DOM were easily distinguished from those of the catchment sources as revealed by a lower absorption coefficient, lower degree of humification, and higher spectral slopes. The observed DOM properties suggest that the lake DOM may be dominated by smaller molecular size and less condensed structures. For the lake and the upper streams, higher absorption coefficients and fluorescence peak intensities but lower spectral slopes and humification index were found for the premonsoon versus the monsoon season. However, such seasonal differences were less pronounced for the industrial channels in the upper catchments. Three distinctive fluorophore groups including microbial humic-like, tryptophan-like, and terrestrial humic-like fluorescence were decomposed from the fluorescence excitation-emission matrix (EEM) of the DOM samples by parallel factor analysis (PARAFAC) modeling. The microbial humic-like component was the most abundant for the industrial channels, suggesting that the component may be associated with anthropogenic organic pollution. The terrestrial humic-like component was predominant for the upper streams, and its relative abundance was higher for the rainy season. Our principal component analysis (PCA) results demonstrated that exchange of seawater and seasonally variable input of allochthonous DOM plays important roles in determining the characteristics of DOM in the lake.
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Crude oil exposure results in oxidative stress-mediated dysfunctional development and reproduction in the copepod Tigriopus japonicus and modulates expression of cytochrome P450 (CYP) genes.
Aquat. Toxicol.
PUBLISHED: 02-20-2014
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In this study, we investigated the effects of the water-accommodated fraction (WAF) of crude oil on the development and reproduction of the intertidal copepod Tigriopus japonicus through life-cycle experiments. Furthermore, we investigated the mechanisms underlying the toxic effects of WAF on this benthic organism by studying expression patterns of cytochrome P450 (CYP) genes. Development of T. japonicus was delayed and molting was interrupted in response to WAF exposure. Hatching rate was also significantly reduced in response to WAF exposure. Activities of antioxidant enzymes such as glutathione S-transferase (GST), glutathione reductase (GR), and catalase (CAT) were increased by WAF exposure in a concentration-dependent manner. These results indicated that WAF exposure resulted in oxidative stress, which in turn was associated with dysfunctional development and reproduction. To evaluate the involvement of cytochrome P450 (CYP) genes, we cloned the entire repertoire of CYP genes in T. japonicus (n=52) and found that the CYP genes belonged to five different clans (i.e., Clans 2, 3, 4, mitochondrial, and 20). We then examined expression patterns of these 52 CYP genes in response to WAF exposure. Three TJ-CYP genes (CYP3024A2, CYP3024A3, and CYP3027C2) belonging to CYP clan 3 were significantly induced by WAF exposure in a time- and concentration-dependent manner. We identified aryl hydrocarbon responsive elements (AhRE), xenobiotic responsive elements (XREs), and metal response elements (MRE) in the promoter regions of these three CYP genes, suggesting that these genes are involved in detoxification of toxicants. Overall, our results indicate that WAF can trigger oxidative stress and thus induce dysfunctional development and reproduction in the copepod T. japonicus. Furthermore, we identified three TJ-CYP genes that represent potential biomarkers of oil pollution.
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Cigarette smoke-induced interleukin-1 alpha may be involved in the pathogenesis of adult acne.
Ann Dermatol
PUBLISHED: 02-17-2014
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Lipid peroxide (LPO) in comedones, which are produced as a result of sebum oxidation, might potentially induce interleukin-1? (IL-1?) and exacerbate comedogenesis and inflammatory changes in comedones.
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Characterization and source identification of organic matter in view of land uses and heavy rainfall in the Lake Shihwa, Korea.
Mar. Pollut. Bull.
PUBLISHED: 02-06-2014
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The characteristics and sources of organic matter in water of the Lake Shihwa, which receives inputs from rural, urban, and industrial areas, were evaluated by examining the biodegradable organic carbon concentration, fluorescence spectra, and carbon and nitrogen isotope ratios, especially during rainy season and dry season. The organic matter transported from rural areas was of refractory nature, while that of industrial origin decomposed rapidly. As compared to the dry season, the organic matter in the rainy season was characterized by a reduced labile fraction. During the dry season, the autochthonous organic matter dominated in the lake, however, the contributions of allochthonous organic sources by industrial and rural areas significantly increased at rainy season. This investigation revealed that the transport of organic matter of anthropogenic origin to the Lake Shihwa was mainly influenced by heavy rainfall. Moreover, each anthropogenic source could differently influence the occurrence of organic matter in water of the Lake Shihwa.
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Algal photosynthetic responses to toxic metals and herbicides assessed by chlorophyll a fluorescence.
Ecotoxicol. Environ. Saf.
PUBLISHED: 01-28-2014
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Chlorophyll a fluorescence is established as a rapid, non-intrusive technique to monitor photosynthetic performance of plants and algae, as well as to analyze their protective responses. Apart from its utility in determining the physiological status of photosynthesizers in the natural environment, chlorophyll a fluorescence-based methods are applied in ecophysiological and toxicological studies to examine the effect of environmental changes and pollutants on plants and algae (microalgae and seaweeds). Pollutants or environmental changes cause alteration of the photosynthetic capacity which could be evaluated by fluorescence kinetics. Hence, evaluating key fluorescence parameters and assessing photosynthetic performances would provide an insight regarding the probable causes of changes in photosynthetic performances. This technique quintessentially provides non-invasive determination of changes in the photosynthetic apparatus prior to the appearance of visible damage. It is reliable, economically feasible, time-saving, highly sensitive, versatile, accurate, non-invasive and portable; thereby comprising an excellent alternative for detecting pollution. The present review demonstrates the applicability of chlorophyll a fluorescence in determining photochemical responses of algae exposed to environmental toxicants (such as toxic metals and herbicides).
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Ferroelectric coupling effect on the energy-band structure of hybrid heterojunctions with self-organized P(VDF-TrFE) nanomatrices.
Adv. Mater. Weinheim
PUBLISHED: 01-25-2014
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Ferroelectric coupling effects on the energy-band structure of hybrid heterojunctions are investigated using hybrid photovoltaic devices with poly(3-hexylthiophene-2,5-diyl) (P3HT)/ZnO and poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)). The self-organized P(VDF-TrFE):P3HT photoactive layer forms a novel architecture consisting of P3HT domains in a P(VDF-TrFE) matrix. The energy-band structure at the interface of the p-n heterojunction is tuned by artificial control of the ferroelectric polarization of the P(VDF-TrFE) material, consequently modulating the photovoltaic performance of the hybrid photovoltaic devices.
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Production of 5,8-dihydroxy-9,12(Z,Z)-octadecadienoic acid from linoleic acid by whole recombinant Escherichia coli cells expressing diol synthase from Aspergillus nidulans.
Appl. Microbiol. Biotechnol.
PUBLISHED: 01-24-2014
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Diol synthase from Aspergillus nidulans was cloned and expressed in Escherichia coli. Recombinant E. coli cells expressing diol synthase from A. nidulans converted linoleic acid to a product that was identified as 5,8-dihydroxy-9,12(Z,Z)-octadecadienoic acid by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The recombinant cells and the purified enzyme showed the highest activity for linoleic acid among the fatty acids tested. The optimal reaction conditions for the production of 5,8-dihydroxy-9,12(Z,Z)-octadecadienoic acid from linoleic acid using whole recombinant E. coli cells expressing diol synthase were pH 7.5, 35°C, 250 rpm, 5 g l(-1) linoleic acid, 23 g l(-1) cells, and 20% (v/v) dimethyl sulfoxide in a 250-ml baffled flask. Under these optimized conditions, whole recombinant cells expressing diol synthase produced 4.98 g l(-1) 5,8-dihydroxy-9,12(Z,Z)-octadecadienoic acid for 150 min without detectable byproducts, with a conversion yield of 99% (w/w) and a productivity of 2.5 g l(-1) h(-1). This is the first report on the biotechnological production of dihydroxy fatty acid using whole recombinant cells expressing diol synthase.
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Neuroprotective action of deer bone extract against glutamate or A?????-induced oxidative stress in mouse hippocampal cells.
J Med Food
PUBLISHED: 01-24-2014
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Water extracts of deer bone, called nokgol in Korean, and deer antlers have been traditionally used as anti-aging medicines. Deer antler extract is known to possess various activities, including anti-aging or anti-amnesic activity. However, there are no reports about the neuroprotective effect of deer bone extract (DBE). The objective of this study was to examine the neuroprotective effect of DBE on glutamate-induced cell death of mouse hippocampal cells (HT-22 cells) and to elucidate the mode of neuroprotective action of DBE. In this study, HT-22 cells was pretreated with DBE before stimulation with glutamate, and then, the effects of DBE on cell viability, oxidative stress markers, and MAP kinases were determined. Separately, the effect of DBE on H?O? or amyloid beta peptide (1-42) (A?????)-induced cytotoxicity of HT-22 cells was evaluated. DBE protected HT-22 cells from glutamate-induced cell death and prevented the increase in lactate dehydrogenase leakage in HT-22 cells. DBE also prevented glutamate-induced oxidative stress, as indicated by increased reactive oxygen species and lipid peroxidation as well as by decreases in glutathione (GSH) levels and GSH peroxidase activity. In addition, DBE inhibited glutamate-induced activation of c-Jun N-terminal kinases (JNK), p38, and extracellular signal-regulated kinase, indicators of oxidative stress-induced cell death. Furthermore, DBE also protected against H?O? and A?????-induced cytotoxicity. These results suggest that DBE may be a useful functional agent for the prevention against neurodegenerative disorders involving oxidative stress.
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Spectroscopic characterization of dissolved organic matter isolates from sediments and the association with phenanthrene binding affinity.
Chemosphere
PUBLISHED: 01-22-2014
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In this study, selected spectroscopic characteristics of sediment organic matter (SOM) were compared and discussed with respect to their different isolation methods, the source discrimination capabilities, and the association with the extent of phenanthrene binding. A total of 16 sediments were collected from three categorized locations including a costal lake, industrial areas, and upper streams, each of which is likely influenced by the organic sources of algal production, industrial effluent, and terrestrial input, respectively. The spectroscopic properties related to aromatic structures and terrestrial humic acids were more pronounced for alkaline extractable organic matter (AEOM) isolates than for the SOM isolates based on water soluble extracts and pore water. The three categorized sampling locations were the most differentiated in the AEOM isolates, suggesting AEOM may be the most representative SOM isolates in terms of describing the chemical properties and the organic sources of SOM. Parallel factor analysis (PARAFAC) based on fluorescence excitation-emission matrix (EEM) showed that a combination of three fluorescent groups could represent all the fluorescence features of SOM. The three categorized sampling locations were well discriminated by the percent distributions of humic-like fluorescent groups of the AEOM isolates. The relative distribution of terrestrial humic-like fluorophores was well correlated with the extent of phenanthrene binding (r=0.571; p<0.05), suggesting that the presence of humic acids in SOM may contribute to the enhancement of binding with hydrophobic organic contaminants in sediments. Principal component analysis (PCA) further demonstrated that the extent of SOM's binding affinity might be affected by the degree of biogeochemical transformation in SOM.
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Highly selective hydrolysis for the outer glucose at the C-20 position in ginsenosides by ?-glucosidase from Thermus thermophilus and its application to the production of ginsenoside F2 from gypenoside XVII.
Biotechnol. Lett.
PUBLISHED: 01-14-2014
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?-Glucosidase from Thermus thermophilus has specific hydrolytic activity for the outer glucose at the C-20 position in protopanaxadiol-type ginsenosides without hydrolysis of the inner glucose. The hydrolytic activity of the enzyme for gypenoside XVII was optimal at pH 6.5 and 90 °C, with a half-life of 1 h with 3 g enzyme l(-1) and 4 g gypenoside XVII l(-1). Under the optimized conditions, the enzyme converted the substrate gypenoside XVII to ginsenoside F2 with a molar yield of 100 % and a productivity of 4 g l(-1) h(-1). The conversion yield and productivity of ginsenoside F2 are the highest reported thus far among enzymatic transformations.
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Association of polymorphisms and haplotypes in the insulin-like growth factor 1 receptor (IGF1R) gene with the risk of breast cancer in Korean women.
PLoS ONE
PUBLISHED: 01-01-2014
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The insulin-like growth factor (IGF) signaling pathway plays an important role in cancer biology. The IGF 1 receptor (IGF1R) overexpression has been associated with a number of hematological neoplasias and solid tumors including breast cancer. However, molecular mechanism involving IGF1R in carcinogenic developments is clearly not known. We investigated the genetic variations across the IGF1R polymorphism and the risk of breast cancer risk in Korean women. A total of 1418 individuals comprising 1026 breast cancer cases and 392 age-matched controls of Korean were included for the analysis. Genomic DNA was extracted from whole blood and single nucleotide polymorphisms (SNPs) were analyzed on the GoldenGate Assay system by Illumina's Custom Genetic Analysis service. SNPs were selected for linkage disequilibrium (LD) analysis by Haploview. We genotyped total 51 SNPs in the IGF1R gene and examined for association with breast cancer. All the SNPs investigated were in Hardy-Weinberg equilibrium. These SNPs tested were significantly associated with breast cancer risk, after correction for multiple comparisons by adjusting for age at diagnosis, BMI, age at menarche, and age at first parturition. Among 51 IGF1R SNPs, five intron located SNPs (rs8032477, rs7175052, rs12439557, rs11635251 and rs12916884) with homozygous genotype (variant genotype) were associated with decreased risk of breast cancer. Fisher's combined p-value for the five SNPs was 0.00032. Three intron located SNPs with heterozygous genotypes also had decreased risk of breast cancer. Seven of the 51 IGF1R SNPs were in LD and in one haplotype block, and were likely to be associated with breast cancer risk. Overall, this case-control study demonstrates statistically significant associations between breast cancer risk and polymorphisms in IGF1R gene.
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Scarring of lupus miliaris disseminatus faciei: treatment with a combination of trichloroacetic acid and carbon dioxide laser.
Dermatol Ther
PUBLISHED: 11-27-2013
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We present a case of a 35-year-old man having a 12-month history of multiple reddish-brown papules on the chin, forehead, cheeks, and eyelids. Histopathologic findings revealed epithelioid cell granulomas with central necrosis consistent with a diagnosis of lupus miliaris disseminatus faciei. After 9 months of combined treatment with ethambutol, rifampin, and pyrazinamide, most lesions gradually resolved but remained as severe disfiguring scars. After 10 sessions of treatments with 100% trichloroacetic acid and CO2 laser, the lupus miliaris disseminatus faciei scars have been much improved and the patient has never experienced a recurrence of disease during subsequent years of follow-up.
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Rejuvenation effects of hyaluronic acid injection on nasojugal groove: Prospective randomized split face clinical controlled study.
J Cosmet Laser Ther
PUBLISHED: 11-19-2013
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Background: Pronounced nasojugal groove (tear trough deformity) is one of the landmarks of aging. Hyaluronic acid filler can be used for attenuating the nasojugal sulcus but irregular lumpness and overcorrection are common adverse reactions. Objectives: We evaluated the effect of Restylane Vital(®) with its specialized injector on volume correction and skin tone of nasojugal groove. Subjects and method: Ten Korean women were enrolled in this study. Subjects were randomized to be injected a stabilized hyaluronic acid-based gel of nonanimal origin (NAHSA injector, Restylane Vital(®), Q-med) on one side of nasojugal groove, with the other side paired as control. The treatment was performed in one session. Outcome assessments included standardized photography, mexameter, and spectrometer for skin tone, global evaluation by blinded investigators, and patients self-assessment. An assessment was made before treatment, immediately after treatment, and 1, 3, and 6 months after the treatment. Results: All patients reported a high degree of satisfaction. Duration of overall effect varied among the patients. Correction of the nasojugal groove with a Restylane Vital(®) injector causes minimal tissue trauma and allows exact placement of hyaluronic acid. Restylane Vital(®) injector offers more predictable results and a lower incidence of adverse effects than more commonly used techniques. Conclusions: Hyaluronic acid filler intradermal injection with special injector is a safe and effective method for correction of nasojugal groove.
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Hydrolysis of Flavanone Glycosides by ?-Glucosidase from Pyrococcus furiosus and Its Application to the Production of Flavanone Aglycones from Citrus Extracts.
J. Agric. Food Chem.
PUBLISHED: 11-14-2013
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The hydrolytic activity of the recombinant ?-glucosidase from Pyrococcus furiosus for the flavanone glycoside hesperidin was optimal at pH 5.5 and 95 °C in the presence of 0.5% (v/v) dimethyl sulfoxide (DMSO) and 0.1% (w/v) Tween 40 with a half-life of 88 h, a Km of 1.6 mM, and a kcat of 68.4 1/s. The specific activity of the enzyme for flavonoid glycosides followed the order hesperidin > neohesperidin > naringin > narirutin > poncirin > diosmin > neoponcirin > rutin. The specific activity for flavanone was higher than that for flavone or flavonol. DMSO at 10% (v/v) was used to increase the solubility of flavanone glycosides as substrates. The enzyme completely converted flavanone glycosides (1 g/L) to flavanone aglycones and disaccharides via one-step reaction. The major flavanone in grapefruit peel, grapefruit pulp, or orange peel extract was naringin (47.5 mg/g), naringin (16.6 mg/g), or hesperidin (18.2 mg/g), respectively. ?-Glucosidase from P. furiosus completely converted naringin and narirutin in 100% (w/v) grapefruit peel extract to 22.5 g/L naringenin after 12 h, with a productivity of 1.88 g L(-1) h(-1); naringin and narirutin in 100% (w/v) grapefruit pulp extract to 8.1 g/L naringenin after 9 h, with a productivity of 0.90 g L(-1) h(-1); and hesperidin in 100% (w/v) orange peel extract to 9.0 g/L hesperetin after 9 h, with a productivity of 1.00 g L(-1) h(-1). The conversion yields, concentrations, and productivities of flavanone aglycones in this study are the highest among those obtained from citrus extracts. Thus, this enzyme may be useful for the industrial hydrolysis of flavanone glycosides in citrus extracts.
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Characterization of a novel recombinant ?-glucosidase from Sphingopyxis alaskensis that specifically hydrolyzes the outer glucose at the C-3 position in protopanaxadiol-type ginsenosides.
J. Biotechnol.
PUBLISHED: 10-12-2013
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A recombinant ?-glucosidase from Sphingopyxis alaskensis with a specific activity of 233.3Umg(-1) was purified by His-trap chromatography. The native enzyme was a 206kDa tetramer. The maximum enzyme activity was observed at pH 5.5 and 50°C. However, above 40°C, the enzyme stability significantly decreased. The enzyme hydrolyzed only the outer glucose at the C-3 position in protopanaxadiol-type ginsenosides without further hydrolysis. Because of the narrow substrate specificity, the enzyme completely converted ginsenosides Rb1, Rb2, Rc, and Rd as substrates to gypenoside XVII, compound O, compound Mc1, and F2, respectively, and it converted ginsenoside Rg3 to Rh2 with a molar conversion yield of 89%. These results suggest that the recombinant ?-glucosidase from S. alaskensis is a potential producer of the rare ginsenosides gypenoside XVII, compound O, compound Mc1, F2, and Rh2. Among ginsenoside substrates, Rb1 was used for the high-level production of the rare ginsenoside gypenoside XVII. The optimum reaction conditions were pH 5.5, 40°C, 0.5mgml(-1) (116.7Uml(-1)) enzyme, and 8.0gl(-1) ginsenoside Rb1. Under these conditions, 6.8gl(-1) gypenoside XVII was produced by the enzyme after 1h with a molar conversion yield of 100% and a productivity of 6.8gl(-1)h(-1).
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Noninvasive assessment of hepatic fibrosis using gadoxetate-disodium-enhanced 3T MRI.
Ann Hepatol
PUBLISHED: 10-12-2013
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Gadoxetate-disodium is a liver-specific MR contrast agent absorbed by hepatocytes via organic anion transporting polypeptide 1B3 and is excreted into the biliary system by multidrug resistance-associated protein 2. It has been suggested that relative parenchymal enhancement on hepatocyte phase image is associated with hepatic function. However, it is not clear whether gadoxetate-disodium-enhanced MRI can be used as a noninvasive fibrosis marker. Thus, the purpose of our study was to evaluate the diagnostic performance of gadoxetate-disodium-enhanced MRI in predicting the hepatic fibrosis stage.
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Doped lanthanum nickelates with a layered perovskite structure as bifunctional cathode catalysts for rechargeable metal-air batteries.
ACS Appl Mater Interfaces
PUBLISHED: 09-23-2013
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Rechargeable metal-air batteries have attracted a great interest in recent years because of their high energy density. The critical challenges facing these technologies include the sluggish kinetics of the oxygen reduction-evolution reactions on a cathode (air electrode). Here, we report doped lanthanum nickelates (La2NiO4) with a layered perovskite structure that serve as efficient bifunctional electrocatalysts for oxygen reduction and evolution in an aqueous alkaline electrolyte. Rechargeable lithium-air and zinc-air batteries assembled with these catalysts exhibit remarkably reduced discharge-charge voltage gaps (improved round-trip efficiency) as well as high stability during cycling.
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Prognostic implications of computed tomographic right ventricular dilation in patients with acute pulmonary embolism.
Thromb. Res.
PUBLISHED: 09-17-2013
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Whether right ventricular (RV) dilation on computerized tomography (RVD-CT) is a useful predictor for clinical outcomes of acute pulmonary embolism (PE) remains debatable. Furthermore, data regarding the best combination of prognostic markers for predicting the adverse outcome of PE are limited.
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The effects of platelet-rich clot releasate on the expression of MMP-1 and type I collagen in human adult dermal fibroblasts: PRP is a stronger MMP-1 stimulator.
Mol. Biol. Rep.
PUBLISHED: 09-14-2013
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Platelet-rich plasma is widely used in acute and chronic ulcers due to its capacity to enhance the wound healing process. Fibroblasts are believed to be the most important cells in the production and remodeling of the extracellular matrix (ECM). Matrix metalloproteinase (MMP)-1 is the proteolytic enzyme of collagen I, and has a key role in collagen remodeling during wound healing. Whether or not platelet-rich clot releasate (PRCR) is able to effectively modulate the ECM, and the effect of PRCR on the expression of type I collagen and MMP-1 in human dermal fibroblasts was evaluated. Specifically, human adult dermal fibroblasts were incubated in PRCR-containing solutions for 24 and 48 h, after which the levels of collagen and MMP-1 were quantified by reverse transcription PCR at the transcriptional level, and ELISA and immunoblot analyses at the post-transcriptional level. PRCR markedly up-regulated the expression of MMP-1 and type I collagen in fibroblasts incubated in 20 % PRCR solutions for 48 h. These findings suggest that increased MMP-1 expression after PRCR treatment enable remodeling the ECM.
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Auricular acupuncture for prehypertension and stage 1 hypertension: study protocol for a pilot multicentre randomised controlled trial.
Trials
PUBLISHED: 09-04-2013
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Hypertension, a worldwide public health problem, is a major risk factor for cardiovascular and kidney disease, and the medical and economic burden of hypertension is increasing. Auricular acupuncture has been used to treat various diseases, including hypertension. Several studies have shown that auricular acupuncture treatment decreases blood pressure in patients with hypertension; however, the scientific evidence is still insufficient. Therefore, we aimed to perform a randomised controlled clinical trial in patients with prehypertension and stage 1 hypertension to evaluate the effect and safety of auricular acupuncture.
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Comparison of Sentinel Lymph Node Biopsy Guided by the Multimodal Method of Indocyanine Green Fluorescence, Radioisotope, and Blue Dye Versus the Radioisotope Method in Breast Cancer: A Randomized Controlled Trial.
Ann. Surg. Oncol.
PUBLISHED: 08-12-2013
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This study aimed to evaluate the identification rate and surgery time of sentinel lymph node biopsy (SLNB) by a multimodal method (MMM) using a mixture of indocyanine green (ICG), radioisotope (RI), and blue dye (BD) compared with the RI alone.
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Characterization of microthermal zones induced by fractional radiofrequency using reflectance confocal microscopy: a preliminary study.
Lasers Surg Med
PUBLISHED: 08-10-2013
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The microthermal zone (MTZ) produced by fractional device have been mostly evaluated through histopathologic analysis. Study of ablative type MTZ created by fractional device and skin thermal interaction using in vivo reflectance confocal microscopy (RCM) has been rarely reported.
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Enhancement of light extraction efficiency of GaN-based light-emitting diodes by ZnO nanorods with different sizes.
J Nanosci Nanotechnol
PUBLISHED: 07-18-2013
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The improvement of the optical output power of GaN-based light emitting diodes (LEDs) was achieved by employing nano-sized flat-top hexagonal ZnO rods. ZnO nanorods (NRs) with the average diameters of 250, 350, and 580 nm were grown on p-GaN top surfaces by a simple wet-chemical method at relatively low temperature (90 degrees C) to investigate the effect of the diameter of ZnO NRs on the light extraction efficiency. Consequently, the enhancement by the factor of as high as 2.63 in the light output intensity at 20 mA for the LED with 350 nm ZnO NRs was demonstrated without the increase in the operation voltage compared to the reference LED.
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Phase 2 Trial of Accelerated, Hypofractionated Whole-Breast Irradiation of 39 Gy in 13 Fractions Followed by a Tumor Bed Boost Sequentially Delivering 9 Gy in 3 Fractions in Early-Stage Breast Cancer.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 07-12-2013
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To report a phase 2 trial of accelerated, hypofractionated whole-breast irradiation (AH-WBI) delivered as a daily dose of 3 Gy to the whole breast followed by a tumor bed boost.
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Production of aglycone protopanaxatriol from ginseng root extract using Dictyoglomus turgidum ?-glycosidase that specifically hydrolyzes the xylose at the C-6 position and the glucose in protopanaxatriol-type ginsenosides.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-11-2013
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The hydrolytic activity of a recombinant ?-glycosidase from Dictyoglomus turgidum that specifically hydrolyzed the xylose at the C-6 position and the glucose in protopanaxatriol (PPT)-type ginsenosides followed the order Rf > Rg1 > Re > R1 > Rh1 > R2. The production of aglycone protopanaxatriol (APPT) from ginsenoside Rf was optimal at pH 6.0, 80 °C, 1 mg ml(-1) Rf, and 10.6 U ml(-1) enzyme. Under these conditions, D. turgidum ?-glycosidase converted ginsenoside R1 to APPT with a molar conversion yield of 75.6 % and a productivity of 15 mg l(-1) h(-1) after 24 h by the transformation pathway of R1 ? R2 ? Rh1 ? APPT, whereas the complete conversion of ginsenosides Rf and Rg1 to APPT was achieved with a productivity of 1,515 mg l(-1) h(-1) after 6.6 h by the pathways of Rf ? Rh1 ? APPT and Rg1 ? Rh1 ? APPT, respectively. In addition, D. turgidum ?-glycosidase produced 0.54 mg ml(-1) APPT from 2.29 mg ml(-1) PPT-type ginsenosides of Panax ginseng root extract after 24 h, with a molar conversion yield of 43.2 % and a productivity of 23 mg l(-1) h(-1), and 0.62 mg ml(-1) APPT from 1.35 mg ml(-1) PPT-type ginsenosides of Panax notoginseng root extract after 20 h, with a molar conversion yield of 81.2 % and a productivity of 31 mg l(-1) h(-1). This is the first report on the APPT production from ginseng root extract. Moreover, the concentrations, yields, and productivities of APPT achieved in the present study are the highest reported to date.
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Primary irritation index and safety zone of cosmetics: Retrospective analysis of skin patch tests in 7,440 Korean women during 12 years.
Int J Cosmet Sci
PUBLISHED: 07-11-2013
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Cosmetics are products used over long periods by the public, and their safety is very important. Several types of human tests are used widely for the evaluation of cosmetics including single patch tests, in-use tests, human repeated insult patch test (HRIPT). However, no clear and well defined published objective and standardized criteria for primary skin irritation in regard to the large variety of cosmetic products.
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The Role of Postmastectomy Radiation Therapy After Neoadjuvant Chemotherapy in Clinical Stage II-III Breast Cancer Patients With pN0: A Multicenter, Retrospective Study (KROG 12-05).
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 07-01-2013
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The purpose of this study was to investigate the role of postmastectomy radiation therapy (PMRT) after neoadjuvant chemotherapy (NAC) in clinical stage II-III breast cancer patients with pN0.
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