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Find video protocols related to scientific articles indexed in Pubmed.
Newcastle disease virus vaccine encapsulated in biodegradable nanoparticles for mucosal delivery of a human vaccine.
Hum Vaccin Immunother
PUBLISHED: 09-30-2014
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An overwhelming number of medicines on the market are oral medicine with the disadvantage of lower bioavailability universally. Newcastle disease (ND) has become a serious disease that threatens the poultry industries in many countries, and there are no treatments available for ND. The biodegradable materials could be surface modified and protect antigen or DNA from damage. Furthermore, nanoparticles are also a potential drug delivery with proper size. However, Newcastle disease virus (NDV) vaccines encapsulated in nanoparticles were widely used due to their proved a high safety and induced quicker and better mucosal and humoral immune responses. Here we review the results of mucosal immune delivery system for ND. Due to the safety, low toxicity, and better immunogenicity of the mucosal immune delivery system, our studies provide a clearly view that used the biodegradable materials to research and develop the human vaccines to save more patients' lives. These promising results provide a foundation for testing the approach in humans.
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Transcriptional regulation of the human TNFSF11 gene in t cells via a cell type-selective set of distal enhancers.
J. Cell. Biochem.
PUBLISHED: 09-01-2014
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In addition to osteoblast lineage cells, the TNF-like factor Receptor Activator of NF-?B ligand (RANKL) is expressed in both B and T cells and may play a role in bone resorption. Rankl expression in mouse T cells is mediated through multiple distal elements marked by increased transcription factor occupancy, histone tail acetylation and RNA polymerase II recruitment. Little is known, however, of the regulation of human RANKL in T cells. Accordingly, we examined the consequence of T cell receptor (TCR) activation on expression of this factor in both Jurkat cells and in primary human T cells. We then explored the mechanism of this regulation by scanning over 400 kb of DNA surrounding the RANKL locus for regulatory enhancers using ChIP-chip analysis. Histone H3/H4 acetylation enrichment identified putative regulatory regions located between -170 and -220 kb upstream of the human RANKL TSS that we designated the human T cell control region (hTCCR). This region showed high sequence conservation with the mouse TCCR. Inhibition of MEK1/2 by U0126 resulted in decreased RANKL expression suggesting that stimulation through MEK1/2 was a prerequisite. ChIP-chip analysis also revealed that c-FOS was recruited to the hTCCR as well. Importantly, both the human RLD5a/b enhancer and segments of the hTCCR mediated robust inducible reporter activity following TCR activation. Finally, SNPs implicated in diseases characterized by dysregulated BMD co-localized to the hTCCR region. We conclude that the hTCCR region contains a cell-selective set of enhancers that plays an integral role in the transcriptional regulation of the TNFSF11 gene in human T cells. J. Cell. Biochem. © 2014 Wiley Periodicals, Inc.
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Image quality and required radiation dose for coronary computed tomography angiography using an automatic tube potential selection technique.
Int J Cardiovasc Imaging
PUBLISHED: 08-29-2014
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To investigate the image quality and the minimum required radiation dose for automatic tube potential selection (ATPS) in dual-source computed tomography (DSCT) coronary computed tomography angiography (CCTA). Three hundred twenty-five consecutive patients (153 men and 172 women) undergoing CCTA were assigned to either the ATPS group (n = 172) or the control group (n = 153); the control group underwent imaging at a constant current of 120 kV. All patients were scanned in either prospectively ECG-triggered high-pitch helical mode or sequential mode. The subjective image quality score, attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), volume CT dose index (CTDIvol), and effective dose (ED) were compared between the two groups with the Student t test or Mann-Whitney U test. The subjective image quality score was not significantly different between the two groups. Imaging noise and attenuation were both significantly higher in the ATPS group than in the control group (imaging noise: 25.6 ± 7.6 versus 15.8 ± 4.0 HU, P < 0.001; attenuation: 559.6 ± 142.0 versus 412.5 ± 64.3 HU, P < 0.001). SNR and CNR were significantly lower in the ATPS group than in the control group (SNR: 23.21 ± 7.40 versus 27.71 ± 8.25, P < 0.001; CNR: 27.81 ± 8.44 versus 33.94 ± 9.69, P < 0.001). ED was significantly lower in the ATPS group than in the control group (ED: 1.25 ± 1.24 versus 2.19 ± 1.77 mSv, P < 0.001). For both groups, ED was significantly lower in the high-pitch mode than in the sequential mode. The use of ATPS for CCTA significantly reduced the radiation dose while maintaining image quality.
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Influence of tube voltage on digitized image qualityof patients exposed to occupational dust: phantoms and clinical studies.
Chin. Med. J.
PUBLISHED: 08-19-2014
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High-voltage analog X-ray examination is a main tool for pneumoconiosis, which is challenged by digital radiography (DR). The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically. We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.
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High-level expression and characterization of bioactive human truncated variant of hepatocyte growth factor in Escherichia coli.
World J. Microbiol. Biotechnol.
PUBLISHED: 08-14-2014
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Hepatocyte growth factor (HGF) is an effective anti-fibrotic factor because of its bioactivity in inhibiting fibrosis-related proteins in the development of hepatic fibrosis. However, high-level production of bioactive mature form HGF is difficult because of its complex structure. Here, we report a non-fusion protein expression system to obtain truncated variant of N-terminal hairpin and first kringle domains of HGF (tvNK1) in Escherichia coli to determine its anti-fibrotic effects on hepatic stellate cells (HSCs). Under the selected conditions of cultivation and isopropyl-?-D-1-thiogalactopyranoside induction, the expression level of tvNK1 accounted for approximately 65 % of the total cellular protein and 50 % of fusion protein in the supernatant of whole cell lysates. The recombinant protein could be purified in one step with Ni(2+)-affinity chromatograph. Finally, about 65 mg recombinant tvNK1 was obtained from 1 l fermentation culture with no <95 % purity. In vitro, the final purified tvNK1 was shown to inhibit the proliferation of HSCs and decrease the mRNA and protein expression levels of fibrosis-related COL1A1 and ?-smooth muscle actin genes.
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Greenhouse gas emissions from cotton field under different irrigation methods and fertilization regimes in arid northwestern China.
ScientificWorldJournal
PUBLISHED: 07-16-2014
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Drip irrigation is broadly extended in order to save water in the arid cotton production region of China. Biochar is thought to be a useful soil amendment to reduce greenhouse gas (GHG) emissions. Here, a field study was conducted to compare the emissions of nitrous oxide (N2O) and methane (CH4) under different irrigation methods (drip irrigation (D) and furrow irrigation (F)) and fertilization regimes (conventional fertilization (C) and conventional fertilization + biochar (B)) during the cotton growth season. The accumulated N2O emissions were significantly lower with FB, DC, and DB than with FC by 28.8%, 36.1%, and 37.6%, while accumulated CH4 uptake was 264.5%, 226.7%, and 154.2% higher with DC, DB, and FC than that with FB, respectively. Irrigation methods showed a significant effect on total global warming potential (GWP) and yield-scaled GWP (P < 0.01). DC and DB showed higher cotton yield, water use efficiency (WUE), and lower yield-scaled GWP, as compared with FC and FB. This suggests that in northwestern China mulched-drip irrigation should be a better approach to increase cotton yield with depressed GHG. In addition, biochar addition increased CH4 emissions while it decreased N2O emissions.
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[Sequence analyses of HIRA gene 3'UTR region and related microRNA].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 06-14-2014
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To explore the HIRA gene sequences of 3'UTR region and elucidate the role of 3'UTR region of HIRA gene in the pathogenesis of tetralogy of Fallot (TOF).
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Thermal diffusion desorption for the comprehensive analysis of organic compounds.
Anal. Chem.
PUBLISHED: 06-10-2014
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Comprehensive analysis of organic compounds is crucial yet challenging considering that information on elements, fragments, and molecules is unavailable simultaneously by current analytical techniques. Additionally, many compounds are insoluble or only dissolve in toxic solvents. A solvent- and matrix-free strategy has been developed which allows the organic compound analyzed in its original form. It utilizes thermal diffusion desorption with the solid analyte irradiated with high energy laser. It is capable of providing explicit elemental, fragmental, and molecular information simultaneously for a variety of organic compounds. Thermal diffusion desorption has many advantages compared to the electrospray and MALDI techniques. The protons that form the protonated molecular ions originate from the analyte itself. All the elements and fragments are also derived from the analyte itself, which provides abundant information and expedites the identification of organic compounds.
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A source of the single-stranded DNA substrate for activation-induced deaminase during somatic hypermutation.
Nat Commun
PUBLISHED: 05-16-2014
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During somatic hypermutation (SHM), activation-induced deaminase (AID) mutates deoxycytidine on single-stranded DNA (ssDNA) generated by the transcription machinery, but the detailed mechanism remains unclear. Here we report a higher abundance of RNA polymerase II (Pol II) at the immunoglobulin heavy-chain variable (Igh-V) region compared with the constant region and partially transcribed Igh RNAs, suggesting a slower Pol II progression at Igh-V that could result in some early/premature transcription termination after prolonged pausing/stalling of Pol II. Knocking down RNA-exosome complexes, which could decrease premature transcription termination, leads to decreased SHM. Knocking down Spt5, which can augment premature transcription termination, leads to increase in both, SHM and the abundance of ssDNA substrates. Collectively, our data support the model that, following the reduction of Pol II progression (pausing or stalling) at the Igh-V, additional steps such as premature transcription termination are involved in providing ssDNA substrates for AID during SHM.
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Experimental study on Qizhu formula for modulating survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells.
Mol Clin Oncol
PUBLISHED: 02-06-2014
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The aim of this study was to investigate the mechanism of action of Qizhu formula, a Chinese medicinal empirical formula, in modulating the action of survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells. Western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) were applied to detect the effect of varying concentrations of Qizhu formula in the modulation of the expression of survivin in MGC-803 human gastric adenocarcinoma cells. The western blot analysis results demonstrated that Qizhu formula exerted no significant effects on the protein expression of the ?-actin housekeeping gene, whereas it exerted a significant inhibitory effect on the protein expression of the apoptosis-related survivin gene at concentrations of 250 ?g/ml and, particularly, 500 ?g/ml. RT-PCR was used to detect the effect of Qizhu formula on survivin mRNA in MGC-803 human gastric adenocarcinoma cells. The ratio of survivin/?-actin in the 0.1% dimethylsulfoxide and the 125, 250 and 500 ?g/ml groups of Qizhu formula was 0.4543, 0.4025, 0.2415 and 0.2235, respectively. Therefore, Qizhu formula exerted a distinct inhibitory effect on the mRNA expression of survivin in MGC-803 cells in a dose-dependent manner. In conclusion, Qizhu formula may modulate the apoptosis of MGC-803 human gastric adenocarcinoma cells, which is associated with the downregulation of survivin mRNA and protein expression.
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Inhibition of transient receptor potential melastatin 7 (TRPM7) channel induces RA FLSs apoptosis through endoplasmic reticulum (ER) stress.
Clin. Rheumatol.
PUBLISHED: 01-23-2014
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Transient receptor potential melastatin 7 (TRPM7) is involved in both normal physiological processes and pathology of various diseases. The purpose of this study was to explore the function and underlying mechanisms of TRPM7 channels in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLSs) apoptosis induced by thapsigargin in vitro. In this study, using a combination of Western blotting, RT-PCR, and nuclear morphology analysis, we investigated the influence and potential function of TRPM7 channels on the apoptosis induced by thapsigargin in RA FLSs. Chemical inhibitors (Gd(3+) and 2-APB) and specific siRNA for TRPM7 were used to study the role of TRPM7 in RA FLSs apoptosis. The expression of TRPM7 was significantly potentiated in RA FLSs. Co-incubation of RA FLSs with Gd(3+), 2-APB, or TRPM7-siRNA increased cell apoptosis. Furthermore, we found that suppression of TRPM7 channels also increased the expression CHOP and calpain and decreased the expression caspase-3. We conclude that suppression of TRPM7 channels may increase RA FLSs apoptosis in vitro, and this is associated with endoplasmic reticulum (ER) stress. Therefore, inhibition of TRPM7 could activate ER stress and induce RA FLSs apoptosis.
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An in situ immobilized pipette tip solid phase microextraction method based on molecularly imprinted polymer monolith for the selective determination of difenoconazole in tap water and grape juice.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-22-2014
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A pipette tip-based molecularly imprinted polymer monolith microextraction (PT-MIPMME) method was developed for the selective extraction of difenoconazole in tap water and grape juice. In this method, molecularly imprinted polymer (MIP) monolith used as the sorbent was synthesized at the tip of a micropipette. This in situ polymerization reaction used difenoconazole as the template and methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and the mixture of toluene-dodecanol as the porogenic solvent. The pipette tip containing MIP monolith was matched to a syringe for performing the polymer monolith microextraction (PMME). Several parameters affecting the proposed PT-MIPMME method were investigated, including the flow rate, sample volume, pH and salt concentration of sample, the type and volume of eluent. Under the optimal conditions, the PT-MIPMME method showed a low limit of detection of 0.5?gL(-1). The recoveries were in the range of 87.6-95.4% with relative standard deviations less than 4.9%. The results showed that difenoconazole was selectively enriched from tap water and grape juice samples.
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Protective Effects of Social Support Content and Support Source on Depression and Its Prevalence 6?Months after Wenchuan Earthquake.
Stress Health
PUBLISHED: 01-12-2014
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A magnitude 8.0 earthquake struck China's southwestern Sichuan province on 12 May 2008. The reported rates of depression symptoms across studies were not consistent, and its protective factors were unknown. This study collected data from Wenchuan earthquake survivors to estimate the prevalence of depression and explore the protective effects of social support and support source on depression. A randomized sampling cross-sectional survey based on community was conducted in January 2009, in Mianzhu and Anxian counties, and 633 survivors were entered into the study. The Chinese edition of the Center for Epidemiologic Studies Depression Scale and the Social Support Rating Scale were used to investigate depression and social support. The prevalence of probable depression in adults 6?months after the Wenchuan earthquake was 22.9% (145/633). Total social support, subjective support, support use and support from family members, neighbours and organizations negatively predicted depression. According to the results, depression was common 6?months after this major disaster. Total social support, subjective support, support use and support from family members, neighbours and organizations were all protective factors for depression after a major disaster. Copyright © 2014 John Wiley & Sons, Ltd.
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Post-traumatic stress disorder among adult survivors of the Wenchuan earthquake in China: a repeated cross-sectional study.
J Anxiety Disord
PUBLISHED: 01-07-2014
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The objective of the study was to examine trends in the prevalence of Posttraumatic Stress Disorder (PTSD) in Wenchuan, China, over the four-year period following its 2008 earthquake, and to explore the risk factors related to current PTSD. Chi-square analysis and multivariate logistic regression analysis were used to assess PTSD morbidity and identify associated risk factors. The results indicated that the prevalence of PTSD was 58.2% at two months, 22.10% at 8 months, 19.8% at 14 months, 19.0% at 26 months, and 8.0% at about 44 months after the earthquake. Female gender, being married, low education, non-drinking, and poor self-perceived health status were significantly associated with PTSD during the early period following the earthquake. Depression was significantly associated with survivors' PTSD throughout the study period.
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Impact of Emphysema Heterogeneity on Pulmonary Function.
PLoS ONE
PUBLISHED: 01-01-2014
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To investigate the association between emphysema heterogeneity in spatial distribution, pulmonary function and disease severity.
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A High-Density Genetic Map Identifies a Novel Major QTL for Boron Efficiency in Oilseed Rape (Brassica napus L.).
PLoS ONE
PUBLISHED: 01-01-2014
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Low boron (B) seriously limits the growth of oilseed rape (Brassica napus L.), a high B demand species that is sensitive to low B conditions. Significant genotypic variations in response to B deficiency have been observed among B. napus cultivars. To reveal the genetic basis for B efficiency in B. napus, quantitative trait loci (QTLs) for the plant growth traits, B uptake traits and the B efficiency coefficient (BEC) were analyzed using a doubled haploid (DH) population derived from a cross between a B-efficient parent, Qingyou 10, and a B-inefficient parent, Westar 10. A high-density genetic map was constructed based on single nucleotide polymorphisms (SNPs) assayed using Brassica 60 K Infinium BeadChip Array, simple sequence repeats (SSRs) and amplified fragment length polymorphisms (AFLPs). The linkage map covered a total length of 2139.5 cM, with 19 linkage groups (LGs) and an average distance of 1.6 cM between adjacent markers. Based on hydroponic evaluation of six B efficiency traits measured in three separate repeated trials, a total of 52 QTLs were identified, accounting for 6.14-46.27% of the phenotypic variation. A major QTL for BEC, qBEC-A3a, was co-located on A3 with other QTLs for plant growth and B uptake traits under low B stress. Using a subset of substitution lines, qBEC-A3a was validated and narrowed down to the interval between CNU384 and BnGMS436. The results of this study provide a novel major locus located on A3 for B efficiency in B. napus that will be suitable for fine mapping and marker-assisted selection breeding for B efficiency in B. napus.
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Chitosan-coated poly(lactic-co-glycolic) acid nanoparticles as an efficient delivery system for Newcastle disease virus DNA vaccine.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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We determined the efficacy and safety of chitosan (CS)-coated poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) as a delivery system for a vaccine to protect chickens against Newcastle disease virus (NDV). The newly constructed vaccine contained DNA (the F gene) of NDV. The Newcastle disease virus (NDV) F gene deoxyribonucleic acid (DNA) plasmid (pFDNA)-CS/PLGA-NPs were spherical (diameter =699.1 ± 5.21 nm [mean ± standard deviation]) and smooth, with an encapsulation efficiency of 98.1% and a Zeta potential of +6.35 mV. An in vitro release assay indicated that CS controlled the burst release of plasmid DNA, such that up to 67.4% of the entire quantity of plasmid DNA was steadily released from the pFDNA-CS/PLGA-NPs. An in vitro expression assay indicated that the expression of nanoparticles (NPs) was maintained in the NPs. In an immunization test with specific pathogen-free chickens, the pFDNA-CS/PLGA-NPs induced stronger cellular, humoral, and mucosal immune responses than the plasmid DNA vaccine alone. The pFDNA-CS/PLGA-NPs did not harm 293T cells in an in vitro assay and did not harm chickens in an in vivo assay. Overall, the results indicated that CS-coated PLGA NPs can serve as an efficient and safe mucosal immune delivery system for NDV DNA vaccine.
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Natural variation and genetic analysis of the tiller angle gene MsTAC1 in Miscanthus sinensis.
Planta
PUBLISHED: 01-01-2014
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Biomass yield is an important target trait in Miscanthus breeding for desirable energy crops. Tiller angle is a key trait of plant architecture because it determines planting density and further influences biomass yield through affecting photosynthesis efficiency. TAC1, a major gene involved in tiller and leaf angle control in rice and maize, respectively, has been extensively studied. Nucleotide variation at this gene, MsTAC1, was investigated in 33 Miscanthus sinensis accessions collected from different areas in China, and one genotype of Miscanthus × giganteus. A total of 136 loci, including 129 single base substitutions and seven InDels, occurred within the MsTAC1 gene of 1,874 bp. The genetic diversity at MsTAC1 is characterized by high nucleotide diversity (? value) and high heterozygosity. Clustering analysis indicated that the phylogenetic tree of the 33 M. sinensis accessions was correlated with their geographical sites of origin. The neutrality test revealed no strong selection pressure on coding and non-coding region variations of the MsTAC1 gene in the accessions. Phenotype evaluations were conducted for tiller angle and five other traits in the Miscanthus panels in the first two growth years of 2009 and 2010. Analysis of variance showed significant phenotypic variations in the examined traits. Association analysis using 246 markers detected 88 loci associated with all the test traits in either 1 or 2 years, and 11 of the 88 were year reproducible and thus reliable. These associations indicate that the variation of MsTAC1 affects the phenotypic value of the tiller angle, tiller number and biomass yield, suggesting that allelic variation in MsTAC1 affects multiple traits and demonstrates its significance in Miscanthus breeding programs.
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Meta-analysis of interactions between arbuscular mycorrhizal fungi and biotic stressors of plants.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Naturally, simultaneous interactions occurred among plants, herbivores, and soil biota, that is, arbuscular mycorrhizal fungi (AMF), nematodes, and fungal pathogens. These multiple interactions play fundamental roles in driving process, structure, and functioning of ecosystems. In this study, we conducted a meta-analysis with 144 papers to investigate the interactions between AMF and plant biotic stressors and their effects on plant growth performance. We found that AMF enhanced plant tolerance to herbivores, nematodes, and fungal pathogens. We also found reciprocal inhibition between AMF and nematodes as well as fungal pathogens, but unidirectional inhibition for AMF on herbivores. Negative effects of AMF on biotic stressors of plants depended on herbivore feeding sites and actioning modes of fungal pathogens. More performance was reduced in root-feeding than in shoot-feeding herbivores and in rotting- than in wilt-fungal pathogens. However, no difference was found for AMF negative effects between migratory and sedentary nematodes. In return, nematodes and fungal pathogens generated more reduction of root colonization in Non-Glomeraceae than in Glomeraceae. Our results suggested that AMF positive effects on plants might be indirectly mediated by competitive inhibition with biotic stressors of plants. These positive and negative interactions make potential contributions to maintaining ecosystem stability and functioning.
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Analgesic effect of acupuncture at hegu (LI 4) on transvaginal oocyte retrieval with ultrasonography.
J Tradit Chin Med
PUBLISHED: 09-13-2013
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To observe the analgesic effect of acupuncture at Hegu (LI 4) in vitro fertilization-embryo transfer (IVF-ET) transvaginal oocyte retrieval using ultrasonography and explore its mechanism.
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Alleviating the pain of unresectable hepatic tumors by percutaneous cryoablation: experience in 73 patients.
Cryobiology
PUBLISHED: 08-30-2013
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Pain caused by liver tumors can be alleviated by cryoablation, but little is known about the analgesic effects and duration of pain alleviation. We retrospectively reviewed the changes in the severity of pain before and after percutaneous cryoablation of hepatic tumors. Each patient enrolled in this study had a single hepatic tumor; patients with large tumors (major diameter, P5 cm) underwent transarterial chemoembolization (TACE) first and then cryoablation. Severe abdominal pain that was not controlled with long-lasting oral analgesics was treated with opioid injections. In all 73 study patients, severe abdominal pain was gradually eased 5 days after cryosurgery, completely disappeared after 15 days and did not recur for more than 8 weeks. There were no differences in analgesic effects between patients with hepatocellular carcinomas and those with liver metastasis (P > 0.05). The patients were divided into four groups depending on their pain outcomes: (i) immediate relief (n = 6), severe abdominalgia was no longer present after cryosurgery; (ii) delayed relief (n = 11), severe abdominalgia disappeared gradually within 15 days after the cryosurgery; (iii) always pain-free (n = 39), severe abdominalgia was not present before or after treatment; and (iv) new pain (n = 17), abdominalgia developed after treatment and disappeared within 15 days. In summary, percutaneous cryoablation of hepatic tumors caused short-term pain in some patients, but this pain disappeared within 15 days. Moreover, the pain-relieving effect of this treatment was sustained for at least 8 weeks, without severe side effects.
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Trapping volumetric measurement by multidetector CT in chronic obstructive pulmonary disease: effect of CT threshold.
Med Phys
PUBLISHED: 08-10-2013
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The purpose of this study was to evaluate the effect of various computed tomography (CT) thresholds on trapping volumetric measurements by multidetector CT in chronic obstructive pulmonary disease (COPD).
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Pathways to psychiatric care in urban north China: a general hospital based study.
Int J Ment Health Syst
PUBLISHED: 07-27-2013
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Pathway studies highlight the help-seeking behaviors of patients with physical and mental illnesses. A number of studies in this field have been completed in various parts of the world. The purpose of this study is to explore the characteristics of the help-seeking pathways of patients with mental illness from urban north China at Mental Health Professional (MHP).
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Rosiglitazone alleviates injury in rats with adenine?induced chronic kidney disease.
Mol Med Rep
PUBLISHED: 05-29-2013
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Rosiglitazone (ROG) has been shown to exert beneficial effects on glycemic control and renal protection. Circulatory fibroblast growth factor?23 (FGF?23) is a novel independent risk factor for chronic kidney disease (CKD) progression. The current study focused on how ROG impacts on injury of the kidney, and whether FGF?23 is involved in the process. A total of 24 male Sprague Dawley rats, weighing 250?280 g, were divided into four groups (n=6 per group): i) Normal; ii) ROG controls, treated with ROG (10 mg/kg/day); iii) CKD models, treated with adenine (200 mg/kg/day); and iv) ROG treatment, treated with ROG (10 mg/kg/day) and adenine (200 mg/kg/day). The rats were sacrificed after four weeks, and serum, urine and kidney tissues were collected. The data revealed that the serum levels of inorganic phosphate (Pi), intact parathyroid hormone (iPTH) and FGF?23 were significantly higher in the CKD models compared with those in the normal group (P<0.01), while ROG significantly reduced the serum levels of Pi, iPTH and FGF?23 (P<0.01). The ratio of protein/creatine (Cr) in the urine and the serum levels of Cr, blood urea nitrogen and uric acid were significantly increased in the CKD models compared with the normal group (P<0.01), however, ROG significantly reduced these parameters (P<0.05). Furthermore, ROG significantly alleviated the tubule interstitial damage index of the CKD models in comparison with that of the controls. These results indicated that ROG mitigates the lesions of chronic kidney disease induced by adenine, and that the system of Pi?PTH?FGF?23 may contribute to this process. The possible mechanisms underlying this process require confirmation in future studies.
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Pathways to psychiatric care of patients from rural regions: A general-hospital-based study.
Int J Soc Psychiatry
PUBLISHED: 05-23-2013
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BACKGROUND: Pathway studies highlight the help-seeking behaviours of patients with physical and mental illness. A number of these studies have been completed in other countries, but there have been few reports from China. Therefore, this study was planned to explore the characteristics of the help-seeking pathways of patients with mental illness from rural regions of China through the mental health professionals and treatment at the General Hospital of the Peoples Liberation Army (PLAGH). METHODS: The pathway diagrams were documented for 203 subjects with various mental disorders using the translated version of the World Health Organization (WHO) pathway encounter form. The patterns of help-seeking and durations were analysed, and the ?(2) test and Mann-Whitney U test were employed as needed. RESULTS: On average, each patient consulted 3.6 caregivers. The vast majority of patients first visited local secondary general hospitals (SGHs) (35.5%, ?(2) = 41.93, p < .0001) or local tertiary general hospitals (TGHs) (32%, ?(2) = 36.21, p < .0001); however, 75.4% of them had not received professional diagnosis and treatment. The patients who first contacted the psychiatric service, finally reached the PLAGH, because of poor treatment or the high cost of medical care. CONCLUSION: The subjects first seek the help of various sources before attending PLAGH due to a lack of awareness of the treatment services and the fear of the stigma associated with mental disorders. The primary care, even the local general hospital, did not act as a gatekeeper to psychiatric services.
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Therapeutic outcomes of combining cryotherapy, chemotherapy and DC-CIK immunotherapy in the treatment of metastatic non-small cell lung cancer.
Cryobiology
PUBLISHED: 05-21-2013
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Currently there are no effective therapies for the treatment of metastatic non-small cell lung cancer (NSCLC). Here, we conducted a retrospective study of 161 patients to evaluate the therapeutic effects of combining cryosurgery, chemotherapy and dendritic cell-activated cytokine-induced killer cells (DC-CIK) immunotherapy. The overall survival (OS) after diagnosis of metastatic NSCLC to patient death was assessed during a 5-years follow-up period. OS of patients who received comprehensive cryotherapy was (median OS, 20 months; n = 86) significantly longer than that of patients who did not received cryotherapy (median OS, 10 months; n = 75; P < 0.0001). Five treatment combinations were selected: chemotherapy (n = 44); chemo-immunotherapy (n = 31); cryo-chemotherapy (n = 32); cryo-immunotherapy (n = 21); and cryo-chemo-immunotherapy (n = 33). A combination of cryotherapy with either chemotherapy or immunotherapy lead to significantly longer OS (18 months and 17 months, respectively) compared to chemotherapy and chemo-immunotherapy (8.5 months and 12 months, respectively; P < 0.001); however, the median OS of patients who underwent cryo-chemo-immunotherapy was significantly longer (27 months) compared to the other treatment programs (P < 0.001). In conclusion, a combination of cryotherapy, chemotherapy and DC-CIK immunotherapy proved the best treatment option for metastatic NSCLC in this group of patients.
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Filter properties of chirped fiber Bragg grating Fabry-Perot cavity: a potential wavelength stabilizer of diode laser.
Appl Opt
PUBLISHED: 05-15-2013
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We investigate filter properties of chirped fiber Bragg grating (CFBG) (Fabry-Perot) F-P cavity through analyzing the coupled wave equation from one-dimensional Helmholtz equation. We derive an approximate formula of the reflectivity of a CFBG F-P cavity, simulate the central wavelength detuning, and calculate the central wavelength shift with the increase of ambient temperature. In the experiments, we measured the spectra of a diode laser with an FBG/CFBG F-P cavity at 0°C-110°C. The experimental results show that the CFBG F-P cavity can help a diode laser to obtain a less central wavelength shift and a narrower 3 dB reflection bandwidth, compared with the FBG F-P cavity at 0°C-110°C. The research results indicate that the CFBG F-P cavity is a potential wavelength stabilizer of uncooled diode laser.
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Development of a simple combining apparatus to perform a magnetic stirring-assisted dispersive liquid-liquid microextraction and its application for the analysis of carbamate and organophosphorus pesticides in tea drinks.
Anal. Chim. Acta
PUBLISHED: 05-06-2013
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This study introduced a simple combining apparatus for performing a magnetic stirring-assisted dispersive liquid-liquid microextraction (MSA-DLLME) for the detection of trace carbamate and organophosphorus pesticides in tea drinks coupled with high performance liquid chromatography. The simple combining apparatus was made up of a sample vial and a cut plastic dropper. The bulb end of the cut plastic dropper was inserted into the neck of the sample vial and the open tip end of the plastic dropper was then cut to an appropriate length. The combining apparatus made was then used to perform the MSA-DLLME. In this experiment, 1-octanol was injected into the tea drink sample solution and the extraction process accelerated by magnetic agitation. The sample solution turned clear and separated into two layers after leaving it alone for several minutes. The cut plastic dropper was gently put down into the sample vial, and then the liquid level of the sample solution elevated up to the tip of the plastic dropper for the collection of low-density extractant. Finally, the collected extractant was drawn out by a microsyringe and injected into the high performance liquid chromatography-diode-array detector for analysis. A series of extraction parameters were investigated and optimized. Under the most favorable conditions, high enrichment factors were obtained for carbofuran, carbaryl and isocarbophos (between 130 and 185). The limits of detection (S/N=3) were in the range of 0.13-0.61 ?g L(-1), and the relative standard deviation varied below 7.8% (n=5). Additionally, good recoveries were obtained between 79.4% and 114.4% in the three tea drinks. The simple combining apparatus utilized in this MSA-DLLME method was shown to be economical, fast, and convenient for the collection of low density extractant.
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Longitudinal study of rural health workforce in five counties in China: research design and baseline description.
Hum Resour Health
PUBLISHED: 04-19-2013
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The village doctors have served rural residents for many decades in China, and their role in rural health system has been highly praised in the world; unfortunately, less attention has been paid to the health workforce during the ambitious healthcare reform in recent years. Therefore, we conducted a longitudinal study to explore the current situation and track the future evolution of the rural healthcare workforce.
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Role of three-body recombination for charge reduction in MALDI process.
Analyst
PUBLISHED: 03-30-2013
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Ions in Matrix-Assisted Laser Desorption/Ionization (MALDI) are predominantly singly charged for small analyte molecules. With the estimated high number density and low temperature of electrons, the three-body recombination mechanism is attractive and should be considered as an important cause for the charge reduction in the plume. Theoretical calculations indicate that the rate coefficient of the three-body recombination is about 50 times higher than that of the two-body recombination if the analyte molecule has insufficient degrees of freedom. Experimental results show that, for small analyte molecules, the ratio of AH2(2+)/AH(+) is close to the theoretical 5% value from the three-body recombination modeling and this ratio declines with the increasing electron and matrix molecule number density caused by greater laser irradiance. The ratio of [A + 2](+)/[A + 1](+) is higher than the theoretical isotopic value, and the excess [A + 2](+) could exclusively result from the three-body recombination collisions. Further evidence demonstrates that [A + 2](+)/[A + 1](+) increases with electron number density, which is in correspondence with the model. All of these theoretical and experimental results indicate that three-body recombination is an essential charge reduction mechanism for small molecules in the MALDI plume.
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Depression and its risk factors among pregnant women in 2008 Sichuan earthquake area and non-earthquake struck area in China.
J Affect Disord
PUBLISHED: 03-14-2013
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On May 12, 2008, a powerful 8.0 magnitude earthquake struck Chinas Sichuan province. While some studies have assessed the mental and physical wellbeing of disaster victims, few have examined the long-term impact of natural disasters on pregnant womens mental health. As such, this study aims to assess whether the Sichuan earthquake continues to negatively affect womens mental health, 4 years since its occurrence. In addition, predictive and protective risk factors of depressive symptoms among pregnant women were also identified.
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Cooling rate optimization for zebrafish sperm cryopreservation using a cryomicroscope coupled with SYBR14/PI dual staining.
Cryobiology
PUBLISHED: 02-18-2013
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The Zebrafish has gained increased popularity as an aquatic model species in various research fields, and its widespread use has led to numerous mutant strains and transgenic lines. This creates the need to store these important genetic materials as frozen gametes. Sperm cryopreservation in zebrafish has been shown to yield very low post-thaw survival and many protocols suffer from great variability and poor reproducibility. The present study was intended to develop a freezing protocol that can be reliably used to cryopreserve zebrafish sperm with high post-thaw survival. In particular, our study focused on cooling protocol optimization with the aid of cryomicroscopy. Specifically, sperm suspended in 8% DMSO or 4% MeOH were first incubated with live/dead fluorescent dyes (SYBR14/PI) and then cooled at various rates from 4°C to different intermediate stopping temperatures such as -10, -20, -30 and -80°C before rewarming to 35°C at the rate of 100°C/min. %PI-positive (dead) cells were monitored throughout the cooling process and this screening yielded an optimal rate of 25°C/min for this initial phase of freezing. We then tested the optimal cooling rate for the second phase of freezing from various intermediate stopping temperatures to -80°C before plunging into liquid nitrogen. Our finding yielded an optimal intermediate stopping temperature of -30°C and an optimal rate of 5°C/min for this second phase of freezing. When we further applied this two-step cooling protocol to the conventional controlled-rate freezer, the average post-thaw motility measured by CASA was 46.8 ± 6.40% across 11 males, indicating high post-thaw survival and consistent results among different individuals. Our study indicates that cryomiscroscopy is a powerful tool to devise the optimal cooling conditions for species with sperm that are very sensitive to cryodamage.
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Cytotoxic and radical scavenging nor-dammarane triterpenoids from Viburnum mongolicum.
Molecules
PUBLISHED: 01-05-2013
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The ethanol extract of the whole plants of Viburnum mongolicum afforded six new nor-dammarane triterpenoids: 3?,12?-dihydroxy-25,26,27-trinordammara-22-en -24,20-olide (1), 3?,12?-dihydroxy-24?-methoxy-25,26,27-trinordammara-20,24-epoxy (2), 3?-O-acetyl-12?-hydroxy-23,24,25,26,27-hexanordammarane-20-one (3), 12?-O- acetyl-15?-hydroxy-17?-methoxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanrane (4), 12?-O-acetyl-15?,17?-dihydroxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanrane (5), and 12?,15?-dihydroxy-3-oxo-17-en-20,21,22-23,24,25,26,27-octanordammanrane (6), together with two known nor-dammarane triterpenoids, 12?-hydroxy-3-oxo-24?-methoxy- 25,26,27-trinordammara-20,24-epoxy (7) and 3?,12?-dihydroxy-23,24,25,26,27- hexanordammarane-20-one (8). The structures of the isolated compounds were established based on 1D and 2D (¹H-¹H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for cytotoxic potential against seven tumor cell lines and radical scavenging activities. Compounds 4-6 exhibited significant cytotoxic activities against all tested tumor cell lines and radical scavenging activities against ABTS·+ radicals comparable with the standard drug Trolox.
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2, 6-dichlorobenzonitrile Causes Multiple Effects on Pollen Tube Growth beyond Altering Cellulose Synthesis in Pinus bungeana Zucc.
PLoS ONE
PUBLISHED: 01-01-2013
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Cellulose is an important component of cell wall, yet its location and function in pollen tubes remain speculative. In this paper, we studied the role of cellulose synthesis in pollen tube elongation in Pinus bungeana Zucc. by using the specific inhibitor, 2, 6-dichlorobenzonitrile (DCB). In the presence of DCB, the growth rate and morphology of pollen tubes were distinctly changed. The organization of cytoskeleton and vesicle trafficking were also disturbed. Ultrastructure of pollen tubes treated with DCB was characterized by the loose tube wall and damaged organelles. DCB treatment induced distinct changes in tube wall components. Fluorescence labeling results showed that callose, and acidic pectin accumulated in the tip regions, whereas there was less cellulose when treated with DCB. These results were confirmed by FTIR microspectroscopic analysis. In summary, our findings showed that inhibition of cellulose synthesis by DCB affected the organization of cytoskeleton and vesicle trafficking in pollen tubes, and induced changes in the tube wall chemical composition in a dose-dependent manner. These results confirm that cellulose is involved in the establishment of growth direction of pollen tubes, and plays important role in the cell wall construction during pollen tube development despite its lower quantity.
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Small and dim target detection via lateral inhibition filtering and Artificial Bee colony based selective visual attention.
PLoS ONE
PUBLISHED: 01-01-2013
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This paper proposed a novel bionic selective visual attention mechanism to quickly select regions that contain salient objects to reduce calculations. Firstly, lateral inhibition filtering, inspired by the limulus ommateum, is applied to filter low-frequency noises. After the filtering operation, we use Artificial Bee Colony (ABC) algorithm based selective visual attention mechanism to obtain the interested object to carry through the following recognition operation. In order to eliminate the camera motion influence, this paper adopted ABC algorithm, a new optimization method inspired by swarm intelligence, to calculate the motion salience map to integrate with conventional visual attention. To prove the feasibility and effectiveness of our method, several experiments were conducted. First the filtering results of lateral inhibition filter were shown to illustrate its noise reducing effect, then we applied the ABC algorithm to obtain the motion features of the image sequence. The ABC algorithm is proved to be more robust and effective through the comparison between ABC algorithm and popular Particle Swarm Optimization (PSO) algorithm. Except for the above results, we also compared the classic visual attention mechanism and our ABC algorithm based visual attention mechanism, and the experimental results of which further verified the effectiveness of our method.
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Probing and tracking organelles in living plant cells.
Protoplasma
PUBLISHED: 10-18-2011
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Intracellular organelle movements and positioning play pivotal roles in enabling plants to proliferate life efficiently and to survive diverse environmental stresses. The elaborate dissection of organelle dynamics and their underlying mechanisms (e.g., the role of the cytoskeleton in organelle movements) largely depends on the advancement and efficiency of organelle tracking systems. Here, we provide an overview of some recently developed tools for labeling and tracking organelle dynamics in living plant cells.
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Single-molecule analysis of PIP2;1 dynamics and partitioning reveals multiple modes of Arabidopsis plasma membrane aquaporin regulation.
Plant Cell
PUBLISHED: 10-18-2011
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PIP2;1 is an integral membrane protein that facilitates water transport across plasma membranes. To address the dynamics of Arabidopsis thaliana PIP2;1 at the single-molecule level as well as their role in PIP2;1 regulation, we tracked green fluorescent protein-PIP2;1 molecules by variable-angle evanescent wave microscopy and fluorescence correlation spectroscopy (FCS). Single-particle tracking analysis revealed that PIP2;1 presented four diffusion modes with large dispersion of diffusion coefficients, suggesting that partitioning and dynamics of PIP2;1 are heterogeneous and, more importantly, that PIP2;1 can move into or out of membrane microdomains. In response to salt stress, the diffusion coefficients and percentage of restricted diffusion increased, implying that PIP2;1 internalization was enhanced. This was further supported by the decrease in PIP2;1 density on plasma membranes by FCS. We additionally demonstrated that PIP2;1 internalization involves a combination of two pathways: a tyrphostin A23-sensitive clathrin-dependent pathway and a methyl-?-cyclodextrin-sensitive, membrane raft-associated pathway. The latter was efficiently stimulated under NaCl conditions. Taken together, our findings demonstrate that PIP2;1 molecules are heterogeneously distributed on the plasma membrane and that clathrin and membrane raft pathways cooperate to mediate the subcellular trafficking of PIP2;1, suggesting that the dynamic partitioning and recycling pathways might be involved in the multiple modes of regulating water permeability.
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The plasticity of regulatory T cell function.
J. Immunol.
PUBLISHED: 10-17-2011
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Regulatory T cells (T(regs)) can suppress a wide variety of cell types, in diverse organ sites and inflammatory conditions. Whereas T(regs) possess multiple suppressive mechanisms, the number required for maximal function is unclear. Furthermore, whether any interrelationship or cross-regulatory mechanisms exist to orchestrate and control their utilization is unknown. In this study, we assessed the functional capacity of T(regs) lacking the ability to secrete both IL-10 and IL-35, which individually are required for maximal T(reg) activity. Surprisingly, IL-10/IL-35 double-deficient T(regs) were fully functional in vitro and in vivo. Loss of IL-10 and IL-35 was compensated for by a concurrent increase in cathepsin E (Ctse) expression, enhanced TRAIL (Tnfsf10) expression, and soluble TRAIL release, rendering IL-10/IL-35 double-deficient T(regs) functionally dependent on TRAIL in vitro and in vivo. Lastly, whereas C57BL/6 T(regs) are normally IL-10/IL-35 dependent, BALB/c T(regs), which express high levels of cathepsin E and enhanced TRAIL expression, are partially TRAIL dependent by default. These data reveal that cross-regulatory pathways exist that control the utilization of suppressive mechanisms, thereby providing T(reg) functional plasticity.
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Whispering-gallery acoustic sensing: characterization of mesoscopic films and scanning probe microscopy applications.
Rev Sci Instrum
PUBLISHED: 10-07-2011
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Full understanding of the physics underlying the striking changes in viscoelasticity, relaxation time, and phase transitions that mesoscopic fluid-like films undergo at solid-liquid interfaces, or under confinement between two sliding solid boundaries, constitutes one of the major challenges in condensed matter physics. Their role in the imaging process of solid substrates by scanning probe microscopy (SPM) is also currently controversial. Aiming at improving the reliability and versatility of instrumentation dedicated to characterize mesoscopic films, a noninvasive whispering-gallery acoustic sensing (WGAS) technique is introduced; its application as feedback control in SPM is also demonstrated. To illustrate its working principle and potential merits, WGAS has been integrated into a SPM that uses a sharp tip attached to an electrically driven 32-kHz piezoelectric tuning fork (TF), the latter also tighten to the operating microscopes frame. Such TF-based SPMs typically monitor the TFs state of motion by electrical means, hence subjected to the effects caused by the inherent capacitance of the device (i.e., electrical resonance differing from the probes mechanical resonance). Instead, the novelty of WGAS resides in exploiting the already existent microscopes frame as an acoustic cavity (its few centimeter-sized perimeter closely matching the operating acoustic wavelength) where standing-waves (generated by the nanometer-sized oscillations of the TFs tines) are sensitively detected by an acoustic transducer (the latter judiciously placed around the microscopes frame perimeter for attaining maximum detection). This way, WGAS is able to remote monitoring, via acoustic means, the nanometer-sized amplitude motion of the TFs tines. (This remote-detection method resembles the ability to hear faint, but still clear, levels of sound at the galleries of a cathedral, despite the extraordinary distance location of the sound source.) In applications aiming at characterizing the dynamics of fluid-like mesoscopic films trapped under shear between the TF probe and the solid substrate, WGAS capitalizes on the well-known fact that the TFs motion is sensitively affected by the shear-forces (the substrate and its adsorbed mesocopic film playing a role) exert on its tip, which occurs when the latter is placed in close proximity to a solid substrate. Thus, WGAS uses a TF as an efficient transducer sandwiched between (i) the probe (that interact with the substrate and mesoscopic film), and (ii) the acoustic cavity (where an assessment of the probe mechanical motion is obtained). In short, WGAS has capability for monitoring probe-sample shear-force interactions via remote acoustic sensing means. In another application, WGAS can also be used as feedback control of the probes vertical position in SPM. In effect, it is observed that when the microscopes probe stylus approaches a sample, a monotonic change of the WGAS acoustic signal occurs in the last ~20 nm before the probe touches the solid samples surface, which allows implementing an automated-control of the probe-sample distance for safely scanning the tip across the sample surface. This principle is demonstrated by imaging the topographic features of a standard sample. Finally, it is worth to highlight that this alignment-free acoustic-based method offers a very direct assessment of the probes mechanical motion state (the mechanical and the WGAS acoustic frequency responses coincide), which makes the WGAS a convenient metrology tool for studying surface interactions, including interfacial friction at the nanometer scale.
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Isolation of high-quality RNA from Reaumuria soongorica, a desert plant rich in secondary metabolites.
Mol. Biotechnol.
PUBLISHED: 09-03-2011
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RNA isolation is a prerequisite for the study of the molecular mechanisms of stress tolerance in the desert plant Reaumuria soongorica, an extreme xeric semi-shrub. However, R. soongorica that contains high levels of secondary metabolites that co-precipitate with RNA, making RNA isolation difficult. Here the authors propose a new protocol suitable for isolating high-quality RNA from the leaves of R. soongorica. Based on a CTAB method described by Liu et al., the protocol has been improved as follows: the samples were ground with PVPP to effectively inhibit the oxidation of phenolics, contaminating DNA was removed with DNase I, and NaAc was used along with ethanol for precipitation to enhance the RNA yield and shorten the precipitation time. Gel electrophoresis and spectrophotometric analysis indicated that this isolation method provides RNA with no DNA contamination. Moreover, the yield (183.79 ± 40.36 ?g/g) and quality were superior to those using the method of Liu et al., which yields RNA with significant DNA contamination at 126.30 ± 29.43 ?g/g. Gene amplification showed that the RNA obtained using this protocol is suitable for use in downstream molecular procedures. This method was found to work equally well for isolating RNA from other desert plants. Thus, it is likely to be widely applicable.
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Arbitrary phasing technique for two-dimensional coherent laser array based on an active segmented mirror.
Appl Opt
PUBLISHED: 05-27-2011
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We introduce a novel (to the best of our knowledge) phasing technique for a coherent laser array. We have accomplished arbitrary phasing in the interval 0-?. A seven-channel laser array experiment is built for verification. A custom-made beam arraying structure is designed to arrange beamlets into a two-dimensional hexagonal array. In the phase-locking loop, the wavefront sensing is performed interferometrically. An active segmented mirror is used for phasing, and the control signals are generated by the proportional control algorithm. In experiment, all the beamlets have been properly phased, and the experiment of inertia-free beam steering has been accomplished.
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Adsorption of phenolic compounds from aqueous solution using salicylic acid type adsorbent.
J. Hazard. Mater.
PUBLISHED: 03-13-2011
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In this study, 5-aminosalicylic acid (5-ASA) was successfully grafted onto the poly(glycidyl methacrylate) (PGMA) macromolecular chains of PGMA/SiO(2) to obtain adsorbent ASA-PGMA/SiO(2). The adsorption properties of ASA-PGMA/SiO(2) for phenolic compounds were studied through batch and column methods. The experimental results showed that ASA-PGMA/SiO(2) possesses strong adsorption ability for phenolic compounds, and its adsorption capacity for phenol, 4-chlorophenol, and p-nitrophenol reaches 1.0, 1.1, and 1.32 mmolg(-1), respectively. In addition, pH has a great influence on the adsorption capacity. The adsorption isotherm data obeyed the Langmuir model well than Freundlich model. The desorption of phenolic compounds from the ASA-PGMA/SiO(2) adsorbent was most effectively achieved in a 0.1 molL(-1) sodium hydroxide solution. Consecutive adsorption-desorption experiments showed that the ASA-PGMA/SiO(2) adsorbent could be reused almost without any loss in the adsorption capacity.
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The impact of the catastrophic earthquake in Chinas Sichuan province on the mental health of pregnant women.
J Affect Disord
PUBLISHED: 03-10-2011
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On May 12, 2008, a magnitude 8.0 earthquake struck Chinas southwestern Sichuan province. Recent studies have identified mental health problems among the survivors, but little is known about the impact of the Sichuan earthquake on the mental health of pregnant women in the area. The main objective was to assess the impact of the Sichuan earthquake on the mental health of pregnant women in earthquake stricken areas.
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Efficient removal of heavy metal ions from aqueous solution using salicylic acid type chelate adsorbent.
J. Hazard. Mater.
PUBLISHED: 02-05-2011
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In this study, 5-aminosalicylic acid was successfully grafted onto the poly(glycidyl methacrylate) (PGMA) macromolecular chains of PGMA/SiO(2) to obtain a novel adsorbent designated as ASA-PGMA/SiO(2). The adsorption properties of ASA-PGMA/SiO(2) for heavy metal ions were studied through batch and column methods. The experimental results showed that ASA-PGMA/SiO(2) possesses strong chelating adsorption ability for heavy metal ions, and its adsorption capacity for Cu(2+), Cd(2+), Zn(2+), and Pb(2+) reaches 0.42, 0.40, 0.35, and 0.31 mmol g(-1), respectively. In addition, pH has a great influence on the adsorption capacity in the studied pH range. The adsorption isotherm data greatly obey the Langmuir and Freundlich model. The desorption of metal ions from ASA-PGMA/SiO(2) is effective using 0.1 mol l(-1) of hydrochloric acid solution as eluent. Consecutive adsorption-desorption experiments showed that ASA-PGMA/SiO(2) could be reused almost without any loss in the adsorption capacity.
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The chromosome number, karyotype and genome size of the desert plant diploid Reaumuria soongorica (Pall.) Maxim.
Plant Cell Rep.
PUBLISHED: 01-19-2011
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Extreme drought and salt resistant plant Reaumuria soongorica is of great potential for revealing genetic bases unique to naturally stress-tolerant plants. A preliminary genome survey, including chromosome number, karyotype, chromosomal localization of 45S rDNA loci and genome size was conducted with R. soongorica collected from Lanzhou, China. Chromosome counting showed that R. soongorica is diploid with chromosome number of 22. Karyotypical analysis illustrated that the chromosomes size ranges from 3.38 to 5.51 ?m, and the chromosomal formula is 2n = 2x = 22 = 4 m + 14sm + 4st. Fluorescence in situ hybridization revealed that four pairs of 45SrDNA signals were detected at the end of R. soongorica chromosomes. The flow cytometry analysis indicated that the mean C value of R. soongorica is 0.806 pg with predicted genome size of about 778 Mb. The results indicate that the extreme drought and salt resistance of R. soongorica was not attributed to a big and complicate genome and also offer some clues in resolving the problems of taxonomy and evolution in Tamaricaceae.
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Generation of dark hollow beam via coherent combination based on adaptive optics.
Opt Express
PUBLISHED: 09-18-2010
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A novel method for generating a dark hollow beam (DHB) is proposed and studied both theoretically and experimentally. A coherent combination technique for laser arrays is implemented based on adaptive optics (AO). A beam arraying structure and an active segmented mirror are designed and described. Piston errors are extracted by a zero-order interference detection system with the help of a custom-made photo-detectors array. An algorithm called the extremum approach is adopted to calculate feedback control signals. A dynamic piston error is imported by LiNbO3 to test the capability of the AO servo. In a closed loop the stable and clear DHB is obtained. The experimental results confirm the feasibility of the concept.
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Mice lacking the matrix metalloproteinase-9 gene reduce renal interstitial fibrosis in obstructive nephropathy.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 09-15-2010
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Matrix metalloproteinase-9 (MMP-9) is one of the major components of the matrix proteolytic network, and its role in the pathogenesis of renal interstitial fibrosis remains largely unknown. Here, we demonstrate that ablation of MMP-9 attenuated renal interstitial fibrotic lesions in obstructive nephropathy. Mice lacking MMP-9 were less likely to develop morphological injury, which was characterized by a reduced disruption of tubular basement membrane (TBM) and expression of fibronectin as well as deposition of total tissue collagen in the kidneys after sustained ureteral obstruction compared with their wild-type counterparts. Deficiency of MMP-9 blocked tubular epithelial-to-myofibroblast transition (EMT) but did not alter the induction of transforming growth factor (TGF)-?1 axis expression in the obstructed kidneys. In vitro, TBM, which was digested by MMP-9 instead of MMP-9 itself, induces EMT and enhances migration of transformed cells. Thus increased MMP-9 is detrimental in renal interstitial fibrogenesis through a cascade of events that leads to TBM destruction and in turn to promotion of EMT. Our findings establish a crucial and definite importance of MMP-9 in the pathogenesis of renal interstitial fibrosis at the whole-animal level.
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Selective inhibition of PDGFR by imatinib elicits the sustained activation of ERK and downstream receptor signaling in malignant glioma cells.
Int. J. Oncol.
PUBLISHED: 08-25-2010
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Clinical studies using the tyrosine kinase inhibitor, imatinib mesylate (Gleevec®), in glioblastoma, have shown no major inhibition of tumor growth or extension of survival for patients, unlike those in chronic myeloid leukemia (CML) and gastrointestinal stromal tumors. The molecular mechanisms of action of imatinib in glioblastoma cells are still not well understood. In this study, we investigated the effects of imatinib on the platelet derived growth factor receptor (PDGFR) downstream signaling pathways as well as on other cellular functions in human glioblastoma cells. NIH3T3 fibroblast and K562 CML cells were used for comparison. Western blot analysis demonstrated that imatinib was more effective in inhibiting the activated rather than the quiescent forms of the target proteins. Furthermore, the imatinib treatment induced the sustained activation of extracellular signal-regulated kinase (ERK 1/2) signaling as well as components of other downstream signaling pathways, such as PI3K/Akt, STAT3 and p38MAPK. Prior stimulation of the malignant cells with exogenous PDGF-BB partially abrogated this activation. Further analysis indicated that the activation of ERK induced by the imatinib treatment was related to the S-phase re-entry of the cell cycle in one of the three glioma cells. Imatinib significantly inhibited cell migration but not cell growth. The combination treatment of imatinib with a MEK or PI3K inhibitor resulted in significant growth inhibition but did not inhibit cell migration beyond the inhibition achieved with the imatinib treatment alone. The treatment of glioma cells with small interfering RNA inhibiting PDGFRB, however, evoked enhanced Akt signaling. These results indicate that the imatinib treatment of malignant glioma does not result in significant inhibitory effects and should be used with caution.
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Uric acid increases fibronectin synthesis through upregulation of lysyl oxidase expression in rat renal tubular epithelial cells.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 05-19-2010
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Urate is produced as the major end product of purine metabolism. In the last decade, the incidence of hyperuricemia increased markedly, and similar trends in the epidemiology of metabolic syndrome have been observed. Hyperuricemia is associated with renal disease, and recent studies have reported that mild hyperuricemia results in hypertension, intrarenal vascular disease, and renal injury. This has led to the hypothesis that uric acid may contribute to renal fibrosis and progressive renal disease. Our purpose was to investigate the relationship between uric acid and renal tubular injury. We applied the method of intraperitoneal injection of uric acid to generate the hyperuricemic mouse model. Compared with the saline injection group, the expression of lysyl oxidase (LOX) and fibronectin in kidneys was increased significantly in hyperuricemic groups. In vitro, uric acid significantly induced NRK-52E cells to express the ECM marker fibronectin, as well as LOX, which plays a pivotal role in ECM maturation, in a time- and dose-dependent manner. Upregulation of the urate transporter URAT1, which is located in the apical membrane of proximal tubules, sensitized the uric acid-induced fibronectin and LOX induction, while both knocking down URAT1 expression in tubular epithelial cells by RNA interference and inhibiting URAT1 function pharmacologically attenuated LOX and fibronectin expression. Furthermore, knockdown of LOX expression by a small interfering RNA strategy led to a decrease in fibronectin abundance induced by uric acid treatment. In addition, evidence of a uric acid-induced activation of the NF-kappaB signaling cascade was observed. Our findings highlight a need for carefully reevaluating our previous view on the pathological roles of hyperuricemia in the kidney and nephropathy induced by uric acid in clinical practice.
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Autoreactive natural killer T cells: promoting immune protection and immune tolerance through varied interactions with myeloid antigen-presenting cells.
Immunology
PUBLISHED: 05-11-2010
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Natural killer T (NKT) cells are innate T lymphocytes that are restricted by CD1d antigen-presenting molecules and recognize lipids and glycolipids as antigens. NKT cells have attracted attention for their potent immunoregulatory effects. Like other types of regulatory lymphocytes, a high proportion of NKT cells appear to be autoreactive to self antigens. Thus, as myeloid antigen-presenting cells (APCs) such as monocytes, dendritic cells (DCs) and myeloid-derived suppressor cells (MDSCs) constitutively express CD1d, NKT cells are able to interact with these APCs not only during times of immune activation but also in immunologically quiescent periods. The interactions of NKT cells with myeloid APCs can have either pro-inflammatory or tolerizing outcomes, and a central question is how the ensuing response is determined. Here we bring together published results from a variety of model systems to highlight three critical factors that influence the outcome of the NKT-APC interaction: (i) the strength of the antigenic signal delivered to the NKT cell, as determined by antigen abundance and/or T-cell receptor (TCR) affinity; (ii) the presence or absence of cytokines that costimulate NKT cells [e.g. interleukin (IL)-12, IL-18 and interferon (IFN)-alpha]; (iii) APC intrinsic factors such as differentiation state (e.g. monocyte versus DC) and Toll-like receptor (TLR) stimulation. Together with recent findings that demonstrate new links between NKT cell activation and endogenous lipid metabolism, these results outline a picture in which the functions of NKT cells are closely attuned to the existing biological context. Thus, NKT cells may actively promote tolerance until a critical level of danger signals arises, at which point they switch to activating pro-inflammatory immune responses.
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Molecular cloning, in vitro expression and bioactivity of rabbit transforming growth factor-beta receptor type II (rTGF-?RII).
Vet. Immunol. Immunopathol.
PUBLISHED: 03-30-2010
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Transforming growth factor-beta receptor II (TGF-?RII) is an attractive target for anti-scarring therapy in wound healing because it attenuates excessive TGF-? which has pleiotropic effects on the immune system. In the present study, the cDNA of rabbit TGF-?RII (rTGF-?RII) was amplified from rabbit peripheral blood by RT-PCR. The open reading frame of rTGF-?RII encodes a protein consisting of 567 amino acids, which contains a predicted transmembrane domain and a Serine/Threonine protein kinase domain similar to other identified mammalian TGF-?RIIs. The amino acid sequences of the biologically active, soluble rTGF-?RII and mouse, rat, human and chicken counterparts are 81%, 81%, 89% and 61%, respectively, identical. Recombinant soluble rTGF-?RII (rsTGF-?RII) fused with His tag was efficiently expressed in Escherichia coli BL21 (DE3) expression host strain. This fusion proteins molecular weight of ? 19 kDa was identified by SDS-PAGE and Western blotting. In vitro, purified rsTGF-?RII was able to inhibit the proliferation of keloid rabbit fibroblasts and decrease the level of collagen. These findings indicate that rTGF-?RII plays an important role in inhibiting the proliferation of keloid rabbit fibroblasts and provides the basis for investigations on the role of TGF-?RII in this important domestic species.
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The use of cryomicroscopy in guppy sperm freezing.
Cryobiology
PUBLISHED: 01-21-2010
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The present study employed cryomicroscopy to derive an optimal sperm freezing protocol for guppy (Poecilia reticulata) sperm. Evaluation criteria during the freezing-thawing process were assessed for nucleation temperature (Tn), temperature when more than 50% of sperm display bending mid-piece (Tb), temperature when more than 80% of sperm stop moving (Tm), thawing temperature (Tt), and post-thaw motility. We compared four different cryoprotectants: 5% N-dimethyl formamide (DMF), 6% methanol (MEOH), 10% dimethyl sulfoxide (DMSO), and 14% glycerol, as well as glycerol at different concentrations of 7-50%; cooling and rewarming rates ranged from 5 to 100°C/min. The protocol that yielded the highest post-thaw motility was samples suspended in 14% glycerol, cooled at 25°C/min, and thawed at 100°C/min, which was in complete agreement with our previous findings derived from a controlled-rate freezer. In addition, Tb and Tm were found to be negatively correlated with post-thaw motility, suggesting their possible role in predicting freezing success. The present study for the first time demonstrated the usefulness of cryomicroscopy in deriving an optimal sperm freezing protocol for aquatic species.
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Presynaptic external calcium signaling involves the calcium-sensing receptor in neocortical nerve terminals.
PLoS ONE
PUBLISHED: 01-05-2010
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Nerve terminal invasion by an axonal spike activates voltage-gated channels, triggering calcium entry, vesicle fusion, and release of neurotransmitter. Ion channels activated at the terminal shape the presynaptic spike and so regulate the magnitude and duration of calcium entry. Consequently characterization of the functional properties of ion channels at nerve terminals is crucial to understand the regulation of transmitter release. Direct recordings from small neocortical nerve terminals have revealed that external [Ca(2+)] ([Ca(2+)](o)) indirectly regulates a non-selective cation channel (NSCC) in neocortical nerve terminals via an unknown [Ca(2+)](o) sensor. Here, we identify the first component in a presynaptic calcium signaling pathway.
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[Adenovirus mediated IL-24 gene expression suppresses gastric cancer cell growth in vitro].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 12-02-2009
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To study the inhibitory effect of a recombinant adenoviral vector carrying human IL-24 gene on SGC-7901 human gastric cancer cell. We infected the SGC-7901 gastric cancer cells with Ad blank adenovirus at various multiplicity of infection (MOIs) to find the optimal infective dose. The SGC-7901 tumor cells were infected with Ad-IL-24 at the optimal MOI in the following experiments. Adenovirus-mediated IL-24 transcription expression in SGC-7901 cells was examined by RT-PCR. The growth-suppressing effect of Ad-IL-24 on SGC-7901 tumor cells was assessed by MTT assay. Apoptosis and cell cycle of SGC-7901 tumor cells infected with Ad-IL-24 was evaluated by flow cytometer (FCM), respectively. The karyomorphology of apoptotic SGC-7901 tumor cells was examined using Hoechst33258 staining under fluorescence microscopy. The expression of apoptosis-related genes was future determined by semi-quantification RT-PCR; We demonstrated that the MOI of 100 was the optimal infective dose in the study on adenovirus-mediated IL-24 gene transfer into SGC-7901 gastric cancer cell; IL-24 gene mediated by adenovirus could successfully transcribe in SGC-7901 tumor cells; Ad-IL-24 could significantly inhibit SGC-7901 tumor cell growth and induce apoptosis, it also can up-regulate the express of bax, caspase-3 and p53 whilst down-regulate the bcl-2 expression. Thus, adenovirus-mediated IL-24 expression had marked anti-tumor effect in suppressing SGC-7901 human gastric cancer cell growth and inducing apoptosis, which may be closely associated with its up-regulation of bax/bcl-2, caspase-3 and p53.
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[Interleukin 24 inhibits growth and induces apoptosis of osteosarcoma cells MG-63 in vitro and in vivo].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 12-02-2009
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To study the inhibitory effect and anti-cancer mechanisms of interleukin 24 (IL-24) on human osteosarcoma cell MG-63, we delivered IL-24 into MG-63 cells in vitro and in vivo by adenovirus. The expression level of IL-24 was detected by RT-PCR and fluorescence microscope; the growth inhibition, apoptosis rate and apoptosis body were measured by MTT, Flow cytometry and Hoechst staining respectively. Furthermore, we analyzed the expression of bcl-2, bax, caspase3 genes by RT-PCR after overexpression of IL-24. For in vivo study, we first established the MG-63 tumor model by grafting MG-63 cells in athymic nude mice; and then injected Ad-IL-24 into the tumors. Two weeks after injection, we sacrificed the mice, removed the tumors, weighed and calculated the ratios of tumor-suppression. We also detected the expressions of Bcl-2, Bax, Caspase-3 and CD34 with immumohistochemistry. Our in vitro results indicated that Ad-IL-24 was transcribed and translated in MG-63 osteosarcoma cells. More interestingly, IL-24 inhibited the growth of MG-63 cells and induced apoptosis by up-regulation of bax, caspase-3 and down-regulation of bcl-2. The in vivo data showed that IL-24 suppressed the tumor growth conspicuously through down-regulating the expression of bcl-2, and up-regulating the expression of bax, caspase-3. This study would provide evidence for the gene therapy of IL-24 on osteosarcoma.
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Controllable growth and magnetic properties of nickel nanoclusters electrodeposited on the ZnO nanorod template.
Nanotechnology
PUBLISHED: 11-06-2009
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The ZnO nanorods were used as a template to fabricate nickel nanoclusters by electrodeposition. The ZnO nanorod arrays act as a nano-semiconductor electrode for depositing metallic and magnetic nickel nanoclusters. The growth sites of Ni nanoclusters could be controlled by adjusting the applied potential. Under -1.15 V the Ni nanoclusters could be grown on the tips of ZnO nanorods. On increasing the potential to be more negative the ZnO nanorods were covered by Ni nanoclusters. The magnetic properties of the electrodeposited Ni nanoclusters also evolved with the applied potentials.
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Preparation and luminescence properties of lanthanide (Eu3+, Sm3+) complexes and their hectorite-based composites.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 10-31-2009
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The complexes of europium and samarium with phthalates ligands were synthesized and characterized. The luminescence behaviors of the lanthanide complexes as well as their hectorite-based composites were investigated by fluorescence spectra. The results indicated that the lanthanide complexes showed slightly lower intensities in hectorite matrix than that of corresponding pure complexes. The lanthanide ion relative fluorescence intensity (LRFI) was enhanced when the lanthanide complexes were doped into hectorite.
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[Construction of adenovirus vector expressing IL-24 and E1A and its inhibition of SMMC-7721].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 10-20-2009
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We constructed the recombinant adenovirus vector expressing IL-24 and E1A (Ad-IL-24-E1A) and investigated the inhibition of Ad-IL-24-E1A on SMMC-7721 hepatocellular carcinoma in vitro. We amplified IL-24 gene by PCR using pAdTrack-IL-24 as template. The IL-24 gene was cloned into pAdTrack-IRES at the Bgl II and Sal I site to form pAdTrack-IL-24-IRES. E1A digested from pAdTrack-E1A was cloned into the pAdTrack-IL-24-IRES at the Xho I and EcoR V site to form the pAdTrack-IL-24-IRES-E1A. We co-transformed both pAdTrack-IL-24-IRES-E1A and pAdeasy-1 digested by Pme I and packaged to obtain Ad-IL-24-E1A. Ad-IL-24-E1A at 50 MOI infected SMMC-7721 cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay determined cell proliferation. Flow cytometry detected Cell apoptosis. The apoptotic rate of SMMC-7721 cells was 52% 48 h after infection with Ad-IL-24-E1A. The result showed that the growth of SMMC-7721 cells was significantly inhibited by Ad-IL-24-E1A at the MOI of 50.
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The speed of mitochondrial movement is regulated by the cytoskeleton and myosin in Picea wilsonii pollen tubes.
Planta
PUBLISHED: 09-08-2009
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Strategic control of mitochondrial movements and cellular distribution is essential for correct cell function and survival. However, despite being a vital process, mitochondrial movement in plant cells is a poorly documented phenomenon. To investigate the roles of actin filaments and microtubules on mitochondrial movements, Picea wilsonii pollen tubes were treated with two microtubule-disrupting drugs, two actin-disrupting drugs and a myosin inhibitor. Following these treatments, mitochondrial movements were characterized by multiangle evanescent wave microscopy and laser-scanning confocal microscopy. The results showed that individual mitochondria underwent three classes of linear movement: high-speed movement (instantaneous velocities >5.0 microm/s), low-speed movement (instantaneous velocities <5.0 microm/s) and variable-speed movement (instantaneous velocities ranging from 0.16 to 10.35 microm/s). 10 nM latrunculin B induced fragmentation of actin filaments and completely inhibited mitochondrial vectorial movement. Jasplakinolide treatment induced a 28% reduction in chondriome motility, and dramatically inhibition of high-speed and variable-speed movements. Treatment with 2,3-butanedione 2-monoxime caused a 61% reduction of chondriome motility, and the complete inhibition of high-speed and low-speed movements. In contrast to actin-disrupting drugs, microtubule-disrupting drugs caused mild effects on mitochondrial movement. Taxol increased the speed of mitochondrial movement in cortical cytoplasm. Oryzalin induced curved mitochondrial trajectories with similar velocities as in the control pollen tubes. These results suggest that mitochondrial movement at low speeds in pollen tubes is driven by myosin, while high-speed and variable-speed movements are powered both by actin filament dynamics and myosin. In addition, microtubule dynamics has profound effects on mitochondrial velocity, trajectory and positioning via its role in directing the arrangement of actin filaments.
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Optimal neurocontroller synthesis for impulse-driven systems.
Neural Netw
PUBLISHED: 08-12-2009
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This paper presents a new controller design technique for systems driven with impulse inputs. Necessary conditions for optimal impulse control are derived. A neural network structure to solve the resulting equations for optimal control is presented. Solution concepts are illustrated with example problems that exhibit increasing levels of difficulty. Two linear problems, one scalar and one vector and a benchmark nonlinear problem, the Van Der Pol oscillator, are used as case studies. Numerical results show the efficacy of the new solution process for impulse driven systems. Since the theoretical development and the design technique are free from restrictive assumptions, this technique is applicable to many problems in engineering and science.
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Multiple conformation transitions of triple helical lentinan in DMSO/water by microcalorimetry.
J Phys Chem B
PUBLISHED: 07-17-2009
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The hydrogen bonding interactions of the triple helical lentinan, beta-(1-->3)-D-glucan from Lentinus edodes, in the mixtures of dimethyl sulfoxide (DMSO) and water were investigated by light scattering, viscometry, and ultrasensitive differential scanning calorimetry (US-DSC). The results revealed that two conformation transitions occurred in the lentinan solution with an increase of temperature. A reversible transition from triple helix I to triple helix II, namely, from a high degree of immobilization of the backbone to a more freely rotating one, occurred in the temperature range from 8 to 45 degrees C. The other was an irreversible conformation transition from triple helix to single strand flexible chain at 90-140 degrees C, depending on the DMSO concentration. The side chain of the triple helix I lentinan combined with water clusters through hydrogen bonds to form an associating water layer in the first region, leading to a high degree of immobilization of the backbone. However, the side chain could rotate in triple helix II at slightly elevated temperature, as a result of the breaking of the associating structure with relatively lower energy. The second transition resulted from the destruction of the intra- and intermolecular hydrogen bonds in lentinan, which sustain the triple helical structure. Furthermore, the transition in the high temperature region showed high cooperation, suggesting that the intra- and intermolecular hydrogen bonds with the relatively high energy were destructed simultaneously. Therefore, the diversity of the hydrogen bonds created the multiple conformational transitions of the triple helical polysaccharide in the aqueous solution.
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Renaturation of triple helical polysaccharide lentinan in water-diluted dimethylsulfoxide solution.
Carbohydr. Res.
PUBLISHED: 06-16-2009
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Triple helical lentinan, a beta-(1-->3)-D-glucan from Lentinus edodes, was denatured in dimethylsulfoxide (DMSO) into single random coils. The randomly coiled lentinan/DMSO solutions were diluted with pure water to w(H) (the weight fraction of water in the mixed solvent) of 95%, and their intrinsic viscosity [eta], weight-average molecular weight M(w), radius of gyration R(g), and hydrodynamic radius R(h) were investigated at 25 degrees C after over 5-day storage. The [eta] and M(w) values, especially the conformation parameter rho (identical with R(g)/R(h)), of the renatured lentinan were close to those of the originally extracted one, suggesting that random lentinan chains in DMSO were reassembled into triple helical structures. Moreover, the renatured lentinan in 95% water/5% DMSO solution exhibited a unique behavior of triple helical glucans that shear modulus G decreased sharply at temperature from 8.4 degrees C to 13.3 degrees C with increasing temperature, which was ascribed to the intramolecular conformation transition from ordered triple helical I to disordered triple helical II. The AFM images gave was suggested intuitively evidence that the renatured lentinan mainly existed as rod-like chains, supporting that formation of triple helical structure. The optimal lentinan concentration for triple helical configuration formation was estimated to be over 0.04%. The time dependence of R(h) and UV absorption of the water-diluted lentinan/DMSO solution with an indicator of azo dye of Congo red suggested that renaturation of triple helix was a very rapid process. Moreover, the blue-shift of UV-vis absorption spectra suggested that the dye molecules of Congo red were assembled into supramolecular structure in the hydrophobic cavity of the renatured triple helical lentinan. All the results showed that the triple helical structure formed once the randomly coiled lentinan/DMSO was diluted to the final water content of 95%.
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A novel peptide binding to the cytoplasmic domain of class A scavenger receptor reduces lipid uptake in THP-1 macrophages.
Biochim. Biophys. Acta
PUBLISHED: 03-13-2009
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Class A scavenger receptor (SR-A) contributes primarily to lipid accumulation in cells. The cytoplasmic domain of SR-A (CSR-A) is responsible for internalization of the receptor-ligand complex into cells. In the present study we tried to reduce cellular uptake of acetylated low density lipoprotein (AcLDL) by inducing the interaction between the CSR-A and a novel peptide H11, which was screened from a phage-displayed peptide library. When H11 was fused with a cross membrane peptide TAT, the fusion peptide could enter cell efficiently. The peptide H11 inhibited the binding and uptake of DiI-AcLDL and attenuated lipid accumulation in the differentiated human acute monocytic leukemia cell line (THP-1) macrophages. Furthermore, the interaction of peptide H11 with the CSR-A inhibited the expression of SR-A protein as well as the phosphorylation of c-jun N-terminal kinase 2 (JNK2) in cells, which mediates cellular lipid accumulation-related signaling pathways. These results suggest that the CSR-A can be a potential target to prevent lipid accumulation in cells. The peptide H11 may be useful in regulating SR-A functions in macrophages.
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Physicochemical properties and antitumor activities for sulfated derivatives of lentinan.
Carbohydr. Res.
PUBLISHED: 03-06-2009
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Five fractions of lentinan, a beta-(1-->3)-D-glucan bearing beta-(1-->6)-d-glucopyranosyl branches, were treated with chlorosulfonic acid for 90 min at 60 degrees C in pyridine medium to synthesize water-soluble sulfated derivatives having the substitution degree of 1.44-1.76. The (13)C NMR spectra of the sulfated beta-glucans indicated that the C-6 position was preferentially substituted by the sulfate groups. The values of the weight-average molecular weight (M(w)), radius of gyration (s(2)(z)(1/2)), and intrinsic viscosity ([eta]) of the sulfated lentinan fractions were determined by size-exclusion chromatography with multi-angle laser light scattering (SEC-MALLS) and viscometry in 0.15 M aq NaCl at 25 degrees C, respectively. The dependence of [eta] on M(w) for the sulfated lentinan was found to be [eta]=8.93 x 10(-3)M(w)(0.73+/-0.02) (mL/g) in 0.15 M aq NaCl (for M(w) ranging from 14.6 x 10(4) to 50.4 x 10(4)). On the basis of the Yamakawa-Fujii-Yoshizaki (YFY) theory, the conformational parameters of the sulfated lentinan were calculated as 950 nm(-1) for the molar mass per unit contour length (M(L)), 4.8 nm for the persistence length (q), and 13.9 for the characteristic ratio (C(infinity)), indicating relatively extended single flexible chains in solution. The sulfated glucan fractions exhibited in vitro antiproliferative activities against sarcoma 180 (S-180) cells, and their inhibition ratios were lower than that of the triple-helix lentinan, but higher than that for the one with single random-coil lentinan chains.
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Adsorptive removal of Pb(II) by activated carbon prepared from Spartina alterniflora: equilibrium, kinetics and thermodynamics.
Bioresour. Technol.
PUBLISHED: 02-08-2009
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Low-cost activated carbon was prepared from Spartina alterniflora by phosphoric acid activation for the removal of Pb(II) from dilute aqueous solution. The effect of experimental parameters such as pH, initial concentration, contact time and temperature on the adsorption was studied. The obtained data were fitted with the Langmuir and Freundlich equations to describe the equilibrium isotherms. The kinetic data were fitted with the Lagergren-first-order, pseudo-second-order and Elovich models. It was found that pH played a major role in the adsorption process. The maximum adsorption capacity for Pb(II) on S. alterniflora activated carbon (SAAC) calculated from Langmuir isotherm was more than 99 mg g(-1). The optimum pH range for the removal of Pb(II) was 4.8-5.6. The Freundlich isotherm model was found to best describe the experimental data. The kinetic rates were best fitted to the pseudo-second-order model. Thermodynamic study showed the adsorption was a spontaneous exothermic process.
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Actin turnover is required for myosin-dependent mitochondrial movements in Arabidopsis root hairs.
PLoS ONE
PUBLISHED: 02-04-2009
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Previous studies have shown that plant mitochondrial movements are myosin-based along actin filaments, which undergo continuous turnover by the exchange of actin subunits from existing filaments. Although earlier studies revealed that actin filament dynamics are essential for many functions of the actin cytoskeleton, there are little data connecting actin dynamics and mitochondrial movements.
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Recognition of lyso-phospholipids by human natural killer T lymphocytes.
PLoS Biol.
PUBLISHED: 01-22-2009
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Natural killer T (NKT) cells are a subset of T lymphocytes with potent immunoregulatory properties. Recognition of self-antigens presented by CD1d molecules is an important route of NKT cell activation; however, the molecular identity of specific autoantigens that stimulate human NKT cells remains unclear. Here, we have analyzed human NKT cell recognition of CD1d cellular ligands. The most clearly antigenic species was lyso-phosphatidylcholine (LPC). Diacylated phosphatidylcholine and lyso-phosphoglycerols differing in the chemistry of the head group stimulated only weak responses from human NKT cells. However, lyso-sphingomyelin, which shares the phosphocholine head group of LPC, also activated NKT cells. Antigen-presenting cells pulsed with LPC were capable of stimulating increased cytokine responses by NKT cell clones and by freshly isolated peripheral blood lymphocytes. These results demonstrate that human NKT cells recognize cholinated lyso-phospholipids as antigens presented by CD1d. Since these lyso-phospholipids serve as lipid messengers in normal physiological processes and are present at elevated levels during inflammatory responses, these findings point to a novel link between NKT cells and cellular signaling pathways that are associated with human disease pathophysiology.
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Tunable superstructure fiber Bragg grating with chirp-distribution modulation based on the effect of external stress.
Opt Lett
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We report an external stress modulation method for producing a superstructure fiber Bragg grating (FBG) with approximate cascaded resonant cavities composed of different index chirp distributions. The 15 mm uncoated apodized uniform-period FBG is pressed by the vertical stress from the upper 11 pieces of the pattern plate controlled by a piezoelectric ceramic actuator. The piece length is 1 mm, and the interval of the adjacent pieces is 0.4 mm. The reflectivity of the modulated FBG gradually shows six obvious multichannel 75%-85% reflection peaks with the increase of the vertical stress of each pattern-plate piece from 0 to 30 N. The channel spacing is steady at about 10 GHz for a C-band wavelength division multiplexing system.
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The relationship between Internet addiction and depression among migrant children and left-behind children in China.
Cyberpsychol Behav Soc Netw
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With greater Internet availability, the pathological use of the Internet has become an emerging mental health issue among adolescents in China. The objective of this study was to examine the associations between Internet addiction and depression in migrant children (MC) and left-behind children (LBC). The present study was conducted using a cross-sectional design with 3,254 participants (8-17-years old), which included 1143 LBC, 574 MC, and 1287 nonleft-behind rural children (RC) from 12 schools. Youngs 8-item Internet Addiction Scale was used to assess Internet dependency. The Childrens Depression Inventory-Short Form was used to measure child depression. The results showed that the prevalence of depression was 10.9 percent among RC, 19.7 percent among MC, and 14.3 percent among LBC. The prevalence of Internet addiction was 3.7 percent among RC, and was 6.4 percent among MC and 3.2 percent among LBC. Depression was effected by the interaction between types of children and Internet addiction. LBC with Internet addiction (odds ratio [OR], 2.780; 95 percent confidence interval [CI], 1.237-6.248), MC with Internet addiction (OR, 2.922; 95 percent CI, 1.116-7.652), and MC with no Internet addiction (OR, 2.735; 95 percent CI, 1.974-3.789) had higher risks of depression than that for RC with no-Internet addiction. The results indicated that Internet addiction might be associated with an increased risk of depression in LBC, and migration was an important risk factor for child depression.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.