JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Enhanced electrochemiluminescence sensor for detecting dopamine based on gold nanoflower@graphitic carbon nitride polymer nanosheet-polyaniline hybrids.
Analyst
PUBLISHED: 10-31-2014
Show Abstract
Hide Abstract
In this work, an enhanced electrochemiluminescence (ECL) sensor based on gold nanoflower@graphitic carbon nitride polymer nanosheet-polyaniline hybrids (AuNF@g-C3N4-PANI) was prepared for the detection of dapamine (DA). First, the bulk g-C3N4 was prepared through polymerizing melamine under 600 °C. And then the g-C3N4 nanosheet was obtained by ultrasonication-assisted liquid exfoliation of bulk g-C3N4. Finally, polyaniline (PANI) and gold nanoflowers (AuNFs) were successively formed on the g-C3N4 nanosheet through an in situ synthesis method. The resulting AuNF@g-C3N4-PANI hybrids were modified onto the surface of glassy carbon electrode to achieve a sensor (AuNF@g-C3N4-PANI/GCE) for detecting dopamine. Under the optimal conditions, the ECL signal increased linearly with the concentration of dopamine. The linear range of 5.0 × 10(-9) to 1.6 × 10(-6) M was obtained, while the detection limit was 1.7 × 10(-9) M. The prepared sensor exhibited a low detection limit and high sensitivity for the determination of dopamine. The combination of g-C3N4 nanosheet, PANI and AuNF would provide a new opportunity for the ECL sensor.
Related JoVE Video
Genetic variations in the one-carbon metabolism pathway genes and susceptibility to hepatocellular carcinoma risk: a case-control study.
Tumour Biol.
PUBLISHED: 09-24-2014
Show Abstract
Hide Abstract
Hepatocellular carcinoma (HCC) is the sixth common cancer and the third common cause of cancer mortality worldwide. However, the exact molecular mechanism of HCC remains uncertain. Many enzymes are involved in one-carbon metabolism (OCM), and single nucleotide polymorphisms (SNPs) in the corresponding genes may play a role in liver carcinogenesis. In this study, we enrolled 1500 HCC patients and 1500 cancer-free controls, which were frequency-matched by age, gender, and HBV infection status. Then eight SNPs from seven OCM genes (MTHFR, MTR, MTRR, FTHFD, GART, SHMT, and CBS) were evaluated. Results showed that six SNPs (MTHFR rs1801133, MTRR rs2287780, MTRR rs10380, FTHFD rs1127717, GART rs8971, and SHMT rs1979277) were significantly associated with HCC risk in Chinese population, with P values range from 2.26?×?10(-4) to 0.035). The most significant association was detected for GART rs8971. Compared with individuals with the TT genotype, the age- and sex-adjusted odds ratio (OR) for developing HCC was 1.44 (95 % confidence interval (CI): 1.03-2.02) among those with the CC genotype and 1.30 (95 % CI: 1.10-1.53) for those with CT genotype. Under the log-additive model, each additional copy of minor allele C was associated with a 1.28-fold increased risk of HCC (OR?=?1.28, 95 % CI: 1.12-1.45). These findings indicated that genetic variants in OCM genes might contribute to HCC susceptibility.
Related JoVE Video
Sterigmatocystin-induced oxidative DNA damage in human liver-derived cell line through lysosomal damage.
Toxicol In Vitro
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Sterigmatocystin (STC) is a carcinogenic and mutagenic mycotoxin produced by fungi of many Aspergillus species. As a precursor of the aflatoxins, STC is a risk factor of liver cancer. The objective of this study is to investigate STC-induced DNA damage and underlying mechanisms. The single cell gel electrophoresis (SCGE) assay was applied to assess DNA damage induced by STC. To clarify the underlying mechanisms, we measured the intracellular generation of reactive oxygen species (ROS) using dichlorofluorescein diacetate as a fluorochrome. The level of oxidative DNA damage was evaluated by immunocytochemical analysis of 8-hydroxydeoxyguanosine (8-OHdG) and the acridine orange (AO) was used to measure the changes of lysosomal membrane stability. A significant dose-dependent increase of DNA strand breaks was found after treatment with STC (3 and 6?M) respectively for 1h. Increases in ROS level and the expression of 8-OHdG were also observed. A statistically significant increase in AO fluorescence intensity was observed in cells treated with STC (1.5, 3 and 6?M) for 1h. The DNA strand breaks induced by STC were almost prevented in cells pretreated with NH4Cl (10mM) and NAC (10mM) for 1h. Our results thus indicated that STC exerts genotoxic effects on HepG2 cells, most likely through oxidative stress and lysosomal leakage.
Related JoVE Video
Involvement of RhoA/ROCK in insulin secretion of pancreatic ?-cells in 3D culture.
Cell Tissue Res.
PUBLISHED: 08-17-2014
Show Abstract
Hide Abstract
Cell-cell contacts and interactions between pancreatic ?-cells and/or other cell populations within islets are essential for cell survival, insulin secretion, and functional synchronization. Three-dimensional (3D) culture systems supply the ideal microenvironment for islet-like cluster formation and functional maintenance. However, the underlying mechanisms remain unclear. In this study, mouse insulinoma 6 (MIN6) cells were cultured in a rotating 3D culture system to form islet-like aggregates. Glucose-stimulated insulin secretion (GSIS) and the RhoA/ROCK pathway were investigated. In the 3D-cultured MIN6 cells, more endocrine-specific genes were up-regulated, and GSIS was increased to a greater extent than in cells grown in monolayers. RhoA/ROCK inactivation led to F-actin remodeling in the MIN6 cell aggregates and greater insulin exocytosis. The gap junction protein, connexin 36 (Cx36), was up-regulated in MIN6 cell aggregates and RhoA/ROCK-inactivated monolayer cells. GSIS dramatically decreased when Cx36 was knocked down by short interfering RNA and could not be reversed by RhoA/ROCK inactivation. Thus, the RhoA/ROCK signaling pathway is involved in insulin release through the up-regulation of Cx36 expression in 3D-cultured MIN6 cells.
Related JoVE Video
Human G3P[4] rotavirus obtained in Japan, 2013, possibly emerged through a human-equine rotavirus reassortment event.
Virus Genes
PUBLISHED: 07-29-2014
Show Abstract
Hide Abstract
Two novel G3P[4] rotavirus strains were detected from children with acute diarrhea in Sendai, Japan, identified as a G3-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2 genotype constellation by whole-genome sequence analysis. The VP7 gene of the two strains displayed the highest nucleotide sequence identity (91 %) and showed a close genetic relationship (99 % bootstrap value) to an equine rotavirus reported in India. The other gene segments were related to human group A rotaviruses. This report suggests a possible reassortment event between human and equine rotaviruses.
Related JoVE Video
The prevalence of increased serum IgE and Aspergillus sensitization in patients with COPD and their association with symptoms and lung function.
Respir. Res.
PUBLISHED: 07-18-2014
Show Abstract
Hide Abstract
Allergy and Aspergillus hypersensitivity (AH) were shown to be associated with severe symptoms or worse lung function in COPD patients. The prevalence of elevated total IgE (T-IgE) and its association with clinical symptoms and lung function in COPD have not been studied. The prevalence of AH and its correlation with clinical characteristics in a COPD cohort of larger sample size is also lacking.
Related JoVE Video
Expectation in Life Review: A Term of Spiritual Needs Easily Understood by Chinese Hospice Patients.
Am J Hosp Palliat Care
PUBLISHED: 06-26-2014
Show Abstract
Hide Abstract
Terms such as spirituality and spiritual needs are abstract and difficult to understand. Realization of spirituality of hospice patients was premise in addressing expression of their spiritual needs. This study investigated expectations expressed during life review and tried to prove that the expectation was intelligible term for spiritual needs in Chinese hospice from May 2011 to June 2013. Among the 107 recruited patients, families were the most frequent emotion-expressing recipients, and 133 expectations related to patients' spiritual needs were identified. The emotion-expressing recipients and the patient's expectations were not affected by demographic characteristics. The expectations in life review with hospice patients and their families had the features of spiritual essence. The identified expectation contents could be used to address spiritual needs in hospice care in Chinese.
Related JoVE Video
Graphene-multiwall carbon nanotube-gold nanocluster composites modified electrode for the simultaneous determination of ascorbic acid, dopamine, and uric acid.
Appl. Biochem. Biotechnol.
PUBLISHED: 05-13-2014
Show Abstract
Hide Abstract
In this paper, graphene-multiwall carbon nanotube-gold nanocluster (GP-MWCNT-AuNC) composites were synthesized and used as modifier to fabricate a sensor for simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The electrochemical behavior of the sensor was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The combination of GP, MWCNTs, and AuNCs endowed the electrode with a large surface area, good catalytic activity, and high selectivity and sensitivity. The linear response range for simultaneous detection of AA, DA, and UA at the sensor were 120-1,701, 2-213, and 0.7-88.3 ?M, correspondingly, and the detection limits were 40, 0.67, and 0.23 ?M (S/N=3), respectively. The proposed method offers a promise for simple, rapid, selective, and cost-effective analysis of small biomolecules.
Related JoVE Video
[Candidemia combined with bacterial bloodstream infection: analysis of clinical features and associated risk factors].
Zhonghua Jie He He Hu Xi Za Zhi
PUBLISHED: 05-07-2014
Show Abstract
Hide Abstract
To investigate the clinical characteristics of and risk factors for candidemia combined with bacterial bloodstream infection(BSI) by retrospective analysis of cases.
Related JoVE Video
Bioinspired materials: from low to high dimensional structure.
Adv. Mater. Weinheim
PUBLISHED: 04-15-2014
Show Abstract
Hide Abstract
The surprising properties of biomaterials are the results of billions of years of evolution. Generally, biomaterials are assembled under mild conditions with very limited supply of constituents available for living organism, and their amazing properties largely result from the sophisticated hierarchical structures. Following the biomimetic principles to prepare manmade materials has drawn great research interests in materials science and engineering. In this review, we summarize the recent progress in fabricating bioinspired materials with the emphasis on mimicking the structure from one to three dimensions. Selected examples are described with a focus on the relationship between the structural characters and the corresponding functions. For one-dimensional materials, spider fibers, polar bear hair, multichannel plant roots and so on have been involved. Natural structure color and color shifting surfaces, and the antifouling, antireflective coatings of biomaterials are chosen as the typical examples of the two-dimensional biomimicking. The outstanding protection performance, and the stimuli responsive and self-healing functions of biomaterials based on the sophisticated hierarchical bulk structures are the emphases of the three-dimensional mimicking. Finally, a summary and outlook are given.
Related JoVE Video
Association between miR-27a genetic variants and susceptibility to colorectal cancer.
Diagn Pathol
PUBLISHED: 03-25-2014
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) are short, non-coding RNAs that negatively regulate target genes. A single nucleotide polymorphism (SNP) in a miRNA sequence may alter miRNA expression and/or maturation, which was proposed to associate with the development and progression of cancer. The rs895819 polymorphism, located in the terminal loop of pre-miR-27a, has been reported to have relevance to several cancers. In this study, we investigated the possibility of association between polymorphism in rs895819 and susceptibility to colorectal cancer (CRC).
Related JoVE Video
Bisphenol A induces oxidative stress-associated DNA damage in INS-1 cells.
Mutat Res Genet Toxicol Environ Mutagen
PUBLISHED: 02-13-2014
Show Abstract
Hide Abstract
Bisphenol A (BPA), an endocrine disruptor, is widely used to manufacture polycarbonate plastic and epoxy resins. Many studies have demonstrated that BPA can play a role in reproductive toxicity and affect the normal metabolic function. Recent research has shown that BPA can influence the function of pancreatic islets. In this study, our aim is to assess the DNA damage induced by BPA and to clarify the mechanism, by use of rat insulinoma INS-1 cells. INS-1 cells were exposed to different doses of BPA (0, 25, 50, 100?M). We conducted the single-cell gel electrophoresis (SCGE) assay to measure DNA damage, and studied proteins such as p53 and p-Chk2 (T68) by Western blotting, in order to verify the (geno)toxicity of BPA. Moreover, we examined intracellular reactive oxygen species (ROS) and glutathione (GSH) to discuss the possible mechanism of DNA damage. The results show that BPA caused an increased in DNA strand-breaks along with greater DNA migration from the nucleus into the comet tail. The expression of DNA damage-associated proteins (p53 and p-Chk2 (T68)) was significantly increased. The exposure to various doses of BPA caused a significant increase in intracellular ROS and a significant reduction in the level of GSH. N-Acetyl cysteine, an inhibitor of intracellular ROS formation, can significantly reduce the generation of intracellular reactive oxygen.
Related JoVE Video
Dietary trimethylamine N-oxide exacerbates impaired glucose tolerance in mice fed a high fat diet.
J. Biosci. Bioeng.
PUBLISHED: 01-19-2014
Show Abstract
Hide Abstract
Trimethylamine N-oxide (TMAO) is an oxidation product of trimethylamine (TMA) and is present in many aquatic foods. Here, we investigated the effects of TMAO on glucose tolerance in high fat diet (HFD)-fed mice. Male C57BL/6 mice were randomly assigned to the control, high fat (HF), and TMAO groups. The HF group was fed a diet containing 25% fat, and the TMAO group was fed the HFD plus 0.2% TMAO for 4 weeks. After 3 weeks of feeding, oral glucose tolerance tests were performed. Dietary TMAO increased fasting insulin levels and homeostasis model assessment-estimated insulin resistance (HOMA-IR) and exacerbated the impaired glucose tolerance in HFD-fed mice. These effects were associated with the expression of genes related to the insulin signal pathway, glycogen synthesis, gluconeogenesis and glucose transport in liver. mRNA levels of the pro-inflammatory cytokine MCP-1 increased significantly and of the anti-inflammatory cytokine IL-10 greatly decreased in adipose tissue. Our results suggest that dietary TMAO exacerbates impaired glucose tolerance, obstructs the hepatic insulin signaling pathway, and causes adipose tissue inflammation in mice fed a high fat diet.
Related JoVE Video
Overoxidized polyimidazole/graphene oxide copolymer modified electrode for the simultaneous determination of ascorbic acid, dopamine, uric acid, guanine and adenine.
Biosens Bioelectron
PUBLISHED: 01-12-2014
Show Abstract
Hide Abstract
In the present work, a novel strategy based on overoxidized polyimidazole (PImox) and graphene oxide (GO) copolymer modified electrode was proposed for the simultaneous determination of ascorbic acid (AA), dopamine (DA), uric acid (UA), guanine (G) and adenine (A). The copolymer was characterized by the scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). Due to the synergistic effects between PImox and GO, the proposed electrode exhibited excellent electrochemical catalytic activities and high selectivity and sensitivity toward the oxidation of AA, DA, UA, G and A. The peak separations between AA and DA, AA and UA, UA and G, and G and A were 140 mV, 200 mV, 380 mV and 300 mV, respectively. The linear response ranges for AA, DA, UA, G and A were 75-2275 ?M, 12-278 ?M, 3.6-249.6 ?M, 3.3-103.3 ?M and 9.6-215 ?M, respectively, and corresponding detection limits were 18 ?M, 0.63 ?M, 0.59 ?M, 0.48 ?M and 1.28 ?M.
Related JoVE Video
Prevalence of the polycystic ovary syndrome in female residents of Chengdu, China.
Gynecol. Obstet. Invest.
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women. The data on this syndrome in a Chinese community are limited.
Related JoVE Video
Preparation of 2,4-dichlorophenoxyacetic acid imprinted organic-inorganic hybrid monolithic column and application to selective solid-phase microextraction.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-05-2014
Show Abstract
Hide Abstract
An organic-inorganic hybrid molecular imprinting monolith (HMIM) has been prepared, characterized and applied for the determination of 2,4-dichlorophenoxyacetic acid (2,4-D) in rice with high-performance liquid chromatography-photodiodes array detector (HPLC-PAD). By optimizing the polymerization conditions, such as the volume ratio of the inorganic alcoholysate and organic part, the 2,4-D-HMIM was synthesized in a micro pipette tip using acrylamide as the functional monomer, ethylene dimethacrylate as the cross-linker and methanol as the porogenic solvent. The morphology of the monolith was studied by scanning electronmicroscopy and Fourier transform infrared spectra. The imprinted factor of the monolith for 2,4-D reached 3.29. A simple, rapid and sensitive method for the determination of 2,4-D in rice using the HMIM microextraction combined with high-performance liquid chromatography-photodiodes array detector was developed. Some parameters affecting the sample pretreatment were investigated, including the type and volume of eluent, the ?ow rate and volume of sample solution. The assay exhibited a linear dynamic range of 167-4167?g/kg with the correlation coefficient above 0.9972. The detection limit (at S/N=3) was 50?g/kg. The proposed method was successfully applied for the selective determination of 2,4-D in rice.
Related JoVE Video
Subtotal splenectomy for splenomegaly in cirrhotic patients.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
In recent years, the spleen has become to be recognized as the "control center" of the immune-metabolic-endocrine network. However, It is controversial that splenomegaly due to portal hypertension is treated by subtotal splenectomy. The aim of this study was to evaluate the distribution of fibrous tissue, morphology of cells as well as splenic size, hemodynamics, hematological and immunological indexes in the residual spleen after subtotal splenectomy. This information may help finding the basis for the operation of subtotal splenectomy.
Related JoVE Video
Ultra Preconcentration of Polycyclic Aromatic Hydrocarbons in Smoked Bacon by a Combination of SPE and DLLME.
J Chromatogr Sci
PUBLISHED: 08-04-2013
Show Abstract
Hide Abstract
A sample pretreatment method, solid-phase extraction combined with dispersive liquid-liquid microextraction (SPE-DLLME), was established for the sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in smoked bacon samples. In the SPE-DLLME process, three PAHs including naphthalene (Naph), phenanthrene (Phen) and pyrene (Pyr) were extracted from samples and transferred into C18 SPE cartridge. The target analytes were subsequently eluted with 1.2 ml of acetonitrile-dichloromethane (5:1, v/v) mixture solution. The eluent was injected directly into the 5.0 ml ultrapure water in the subsequent DLLME procedure. The sedimented phase was concentrated under a gentle nitrogen flow to 120.0 µl. Finally, the analytes in the extraction solvent were determined by high-performance liquid chromatography with a ultra-violet detector. Some important extraction parameters affecting the performance, such as the sample solution flow rate, breakthrough volume, salt addition as well as the type and volume of the elution solvent were optimized. The developed method provided an ultra enrichment factors for PAHs ranged from 3478 to 3824. The method was applied for the selective extraction and sensitive determination of PAHs in smoked bacon samples. The limits of detection (S/N = 3) were 0.05, 0.01, 0.02 ?g kg(-1) for Naph, Phen, Pyr, respectively.
Related JoVE Video
[Correlation analysis between serum free testosterone and total testosterone in Chengdu females].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 07-18-2013
Show Abstract
Hide Abstract
This paper is aimed to analyze the correlation between serum free testosterone (FT) and total testosterone (TT) to acquire a cutoff about using total testosterone to diagnose hyperandrogenism in Chengdu females. We investigated 1854 women by cluster sampling method, detected their serum FT levels and TT levels, scored relative items, analyzed the correlation and made the ROC curve to get a cutoff of TT levels. Serum FT had a linear correlation with serum TT (r = 0.597, r2 = 0.356, P < 0.001). The cutoff value was 0.635 ng/mL. The specificity and sensitivity were 76.3% and 77.24%, respectively. No correlation found between serum FT and Ferriman-Gallway Score (P = 0.392). Positive correlations were seen between serum FT and Plewig-Kligman Score (r = 0.137, P < 0.001), serum TT and Ferriman-Gallway Score (r = 0.069, P = 0.003) and serum TT and Plewig-Kligman Score (r = 0.092, P < 0.001). There is a linear correlation between serum FT and TT. We can diagnose hyperandrogenism according to the serum TT cutoff value (0.635 ng/mL). Its clinical symptoms are not paralleled with the biochemical test results.
Related JoVE Video
Clinical value of radiofrequency ultrasonic local estimators in classifying breast lesions.
J Ultrasound Med
PUBLISHED: 06-19-2013
Show Abstract
Hide Abstract
We sought to summarize the features of radiofrequency ultrasonic local estimator (RULES) images of benign and malignant masses and to explore the diagnostic value of RULES scores to identify breast lumps.
Related JoVE Video
Imbalance between subpopulations of regulatory T cells in COPD.
Thorax
PUBLISHED: 06-07-2013
Show Abstract
Hide Abstract
Recent evidence indicates that human regulatory T cells (Tregs) are composed of three distinct subpopulations: CD25(++) CD45RA(+) resting Tregs (rTregs), CD25(+++) CD45RA(-) activated Tregs (aTregs), which are suppressive, and CD25(++) CD45RA(-) cytokine-secreting (Fr III) cells with pro-inflammatory capacity.
Related JoVE Video
Eicosapentaenoic acid-enriched phospholipid ameliorates insulin resistance and lipid metabolism in diet-induced-obese mice.
Lipids Health Dis
PUBLISHED: 05-08-2013
Show Abstract
Hide Abstract
Over the past two decades, a striking increase in the number of people with metabolic syndrome (MS) has taken place worldwide. With the elevated risk of not only diabetes but also cardiovascular morbidity and mortality, there is urgent need for strategies to prevent this emerging global epidemic. The present study was undertaken to investigate the effects of dietary eicosapentaenoic acid-enriched phospholipid (EPA-PL) on metabolic disorders.
Related JoVE Video
Low percolation threshold carbon-black/ nitrile-butadiene-rubber composites and their electromagnetic shielding effects.
J Nanosci Nanotechnol
PUBLISHED: 05-08-2013
Show Abstract
Hide Abstract
Nitrile-butadiene-rubber composites, filled with super conducting carbon black, are successfully prepared with low percolation threshold, high conductivity and electromagnetic shielding effectiveness. Percolation theory is used to represent the systems conductivity, and the corresponding result is close to the experimental value. The fitting curve also gives the weight fraction threshold and conductivity exponent of the conducting polymer. The percolation threshold of the composite is 9.2 phr, which is much smaller than previous homologous findings and lower than the value of short carbon fiber counterparts reported. The volume resistivity becomes 3.17 omega x cm for the 20 phr sample and decreases to 0.66 omega x cm for the 40 phr sample. At 1.8 GHz for 40 phr sample, the shielding effectiveness is -43 dB.
Related JoVE Video
Immobilizing Cr3+ with SO3H-functionalized solid polymeric ionic liquids as efficient and reusable catalysts for selective transformation of carbohydrates into 5-hydroxymethylfurfural.
Bioresour. Technol.
PUBLISHED: 05-04-2013
Show Abstract
Hide Abstract
A series of functional polymeric ionic liquids (FPILs) were prepared by coupling of SO3H-functionalized polymeric ionic liquids with different counterpart anions containing or excluding CrCl3·6H2O, and characterized by SEM, FT-IR, XRD, NH3-TPD, TG, melting point, ICP-AES, and TEM. The catalytic activity of the prepared solid FPILs was investigated for the conversion of biomass including fructose, glucose and cellulose into 5-hydroxymethylfurfural (HMF) with the presence of DMSO-mediated solvents, successively producing moderate to excellent yields of HMF under atmospheric pressure. The FPILs catalysts developed in this study present improved performance on fructose-to-HMF conversion over other solid catalysts, such as functional ionic liquids supported by silica, metal oxides and strong acid ion exchange resin catalysts, and can be very easily recycled at least five times without significant loss of activity. In addition, a kinetic analysis was carried out to illustrate the formation of HMF.
Related JoVE Video
Effects of instrument settings on radiofrequency ultrasound local estimator images: a preliminary study in a gallbladder model.
Mol Med Rep
PUBLISHED: 04-18-2013
Show Abstract
Hide Abstract
The aim of the present study was to evaluate the changes in radiofrequency ultrasound local estimator (RULES) images with different instrument settings. An Esaote Technos MPX Color Doppler Ultrasound Machine and RULES were used to capture images of a gallbladder model. The percentages of various colored areas (color filling rates) within the area of interest were calculated using different instrument gains, transducer frequencies and scan depths. Blue was predominant in the lumen of the model gallbladder, while red and green were primarily located near the inner edge of the lumen. When the depth was set at 62 mm and the gain at 105, the total color filling rates did not vary with different transducer frequencies. The blue color filling rate was greatest with a transducer frequency of 8.0 MHz, and the red and green color filling rates were greatest with a frequency of 12.5 MHz. Color variety was greatest when the transducer frequency was 12.5 MHz. When the transducer frequency was 12.5 MHz and the depth was 62 mm, the blue color filling rate was greatest with gains of 105 and 110, the red color filling rate was greatest with gains of 95 and 100 and the green color filling rate was greatest when the gain was 100. The total color filling rate was greatest at gains of 100 and 105. In conclusion, images obtained using RULES may be affected by the instrument gain and, to a certain extent, by transducer frequency.
Related JoVE Video
Preparation, characterization and application of organic-inorganic hybrid caffeine imprinted monolith.
J Chromatogr A
PUBLISHED: 04-09-2013
Show Abstract
Hide Abstract
The present work aims to synthesize an organic-inorganic hybrid caffeine imprinted monolith using one-step method. The synthesis conditions such as the type of inorganic precursor and porogenic solvent, the molar ratios of the monomer and cross-linker, the volume ratio of the inorganic alcoholysate and organic part were optimized. The morphology of the monolith was studied by scanning electron microscopy and Fourier transform infrared spectra. The imprinted factor of the monolith for caffeine reached 3.02. A simple, rapid and sensitive method for the determination of caffeine in childrens milk using the organic-inorganic hybrid caffeine imprinted polymer monolith microextraction combined with high-performance liquid chromatography-photodiodes array detector was developed. Several parameters affecting the sample pretreatment were investigated, including the type, flow rate and volume of eluent, the flow rate and volume of sample solution. The assay exhibited a linear dynamic range of 8-500?gL(-1) with the correlation coefficient above 0.9987. Lower limits of detection (LOD, at S/N=3) and quantification (LOQ, at S/N=10) in childrens milk samples were 2.7 and 8?gL(-1). Recoveries of caffeine from spiked childrens milk ranged from 85 to 104% with relative standard deviations of less than 8.9%.
Related JoVE Video
Polycyclic hybrid isoprenoids from a reed rhizosphere soil derived Streptomyces sp. CHQ-64.
J. Nat. Prod.
PUBLISHED: 04-02-2013
Show Abstract
Hide Abstract
Two new hybrid isoprenoids, named indotertine B (2) and drimentine H (3), along with the known analogue drimentine C (4), were isolated from the reed rhizosphere soil derived actinomycete Streptomyces sp. CHQ-64. The structures of these compounds, including absolute configurations, were elucidated by extensive NMR, MS, and CD analyses. Indotertine B (2) exists as a pair of rotamers about the N-C(O) bond with a 2:1 ratio and displays activities against HCT-8 and A549 tumor cell lines with IC50 values of 6.96 and 4.88 ?M, respectively.
Related JoVE Video
Sparse constrained reconstruction for accelerating parallel imaging based on variable splitting method.
Comput Math Methods Med
PUBLISHED: 02-28-2013
Show Abstract
Hide Abstract
Parallel imaging is a rapid magnetic resonance imaging technique. For the ill-conditioned problem, noise and aliasing artifacts are amplified during the reconstruction process and are serious especially for high accelerating imaging. In this paper, a sparse constrained reconstruction problem is proposed for parallel imaging, and an effective solution based on the variable splitting method is contrived. First-order and second-order norm optimization problems are first split, and then they are transferred to unconstrained minimization problem by the augmented Lagrangian method. At last, first-order norm and second-order norm optimization problems are alternatively resolved by different methods. With a discrepancy principle as the stopping criterion, analysis of simulated and actual parallel magnetic resonance image reconstruction is presented and discussed. Compared with the routine parallel imaging reconstruction methods, the results show that the noise and aliasing artifacts in the reconstructed image are evidently reduced at large acceleration factors.
Related JoVE Video
Effect of instrument settings on liquid-containing lesion images characterized by radiofrequency ultrasound local estimators.
Z Med Phys
PUBLISHED: 02-01-2013
Show Abstract
Hide Abstract
The purpose of this study was to investigate the effects of ultrasonic instrument gain, transducer frequency, and depth on the color variety and color filling of radiofrequency ultrasonic local estimators (RULES) images which indicated specific physical representation of liquid-containing lesions in order to find the optimal settings for the clinical application of RULES in liquid-containing lesions. Changing the ultrasonic instrument gain, transducer frequency, and depth affected the color filling and color variety of 21 pathologically-confirmed liquid-containing lesion images analyzed by RULES. Blue colored fill dominated the RULES images to represent the liquid-containing lesions. A frequency of 12.5MHz led to red and green colors along the inner edges of the liquid-containing lesions. Changing the gain resulted in significantly different blue colored filling that was highest when the gain was 90 to 100. Changing the frequency also significantly changed the blue color filling, with the highest filling occurring at 12.5MHz. Changing the depth did not affect the blue color filling. The liquid components of the lesions may be identified by their characteristic manifestations in RULES, where color variety is affected by transducer frequency and blue color filling which represent liquid-containing lesions in RULES images is affected by frequency and gain.
Related JoVE Video
A case report of a patient in whom antibodies against the 2009 pandemic influenza A/H1N1 virus have been present since June 1999.
Hum Vaccin Immunother
PUBLISHED: 01-16-2013
Show Abstract
Hide Abstract
A 69-y-old man with a history of hepatitis C since May 1985 and his 6 healthy immediate relatives were examined for hemagglutination inhibition antibodies against 2009 pandemic influenza A/H1N1 virus. This patient had a hemagglutination inhibition antibody titer of 640 against 2009 pandemic influenza A/H1N1 virus in a serum sample collected on July 4, 1999, and the antibody titers fluctuated between 40 and 320 in serum samples collected after 1999. The fluctuations in hemagglutination inhibition antibody titers against pandemic 2009 influenza A/H1N1 virus were not consistent with his history of seasonal influenza, and our results suggest a relationship to his vaccination with seasonal trivalent inactivated influenza vaccine. This patient as well as three relatives showed cross-reactive antibody titers of 10 or more against 2009 pandemic A/H1N1 influenza virus in serum samples taken after June 1999. From these results we conclude that the cross-reactivity to pandemic 2009 A/H1N1 influenza virus emerged after June 1999.
Related JoVE Video
Research status and prospect of stem cells in the treatment of diabetes mellitus.
Sci China Life Sci
PUBLISHED: 01-10-2013
Show Abstract
Hide Abstract
Beta cell mass and function are decreased to varying degrees in diabetes. Islet cell replacement or regenerative therapy may offer great therapeutic promise to people with diabetes. In addition to primary pancreatic ? cells, recent studies on regeneration of functional insulin producing cells (IPCs) revealed that several alternative cell sources, including embryonic stem cells, induced pluripotent stem cells and adult stem cells, can generate IPCs by differentiation, reprogramming, and trans-differentiation. In this review, we discuss stem cells as a potential alternative cell source for the treatment of diabetes.
Related JoVE Video
Study on the factors associated with postpartum visits in rural China.
PLoS ONE
PUBLISHED: 01-08-2013
Show Abstract
Hide Abstract
Postpartum visits (PPVs) have been advocated as a way to improve health outcomes for mothers and their infants, but the rate of PPVs is still low in rural China. This study aims to investigate the utilization of PPVs and to explore the factors associated with PPVs in rural China. Parity is the most concerned factor in this study.
Related JoVE Video
A preliminary analysis of the effect of the new rural cooperative medical scheme on inpatient care at a county hospital.
BMC Health Serv Res
PUBLISHED: 01-04-2013
Show Abstract
Hide Abstract
China in 2009 committed to reach universal health coverage by promoting three forms of health insurance; NCMS for the rural population, UEBMI for formally employed urban residents and URBMI for other urban residents. NCMS has expanded to near universal coverage in rural China since launching in 2003. The objective of this study aimed to assess the effect of NCMS on inpatient care utilization from 2003 to 2012 at Longyou county hospital, Zhejiang province.
Related JoVE Video
Inhibition of fibroblast differentiation of muscle-derived stem cells in cell implantation treatment of stress urinary incontinence.
Cell Reprogram
PUBLISHED: 06-30-2011
Show Abstract
Hide Abstract
The aim of this study was to investigate the effects of transforming growth factor-?1 (TGF-?1) stimulation and the blocking of the TGF-?1/Smad3 signaling pathway by vector-mediated Smad3 shRNA on muscle-derived stem cells (MDSCs) in cell implantation treatment of stress urinary incontinence (SUI) of the rat. MDSCs were infected with the GC-shSmad3 lentivirus vector. Five days after infection, the cells were treated with TGF-?1. The expression levels of desmin (a marker of muscle differentiation) and vimentin (a marker of fibroblast differentiation) were tested by real-time PCR and Western blot. GC-shSmad3 lentivirus-infected MDSCs were injected into the bladder neck and proximal urethra of SUI rats. Urodynamic test was used to measure leak point pressure (LPP) at 2 weeks and 4 weeks after MDSC transplantation. Upregulated expression of vimentin and downregulated expression of desmin were found in MDSCs after culture with TGF-?1 in vitro. GC-shSmad3 lentivirus infection inhibited fibroblast differentiation of MDSCs but allowed muscle differentiation with desmin expression. In vivo experiments showed that GC-shSmad3 lentivirus infection could improve MDSC-mediated repairing of urethra sphincter function. In conclusion, blocking Smad3 expression inhibits the fibroblast differentiation of MDSCs induced by TGF-?1 in vitro and improves the repairing of urethral sphincter function by inhibiting the fibroblast differentiation of MDSCs in a rat model of SUI in vivo.
Related JoVE Video
[Studies on chemical constituents from leaves of Uraria lacei].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-28-2011
Show Abstract
Hide Abstract
To study the chemical constituents from leaves of Uraria lacei.
Related JoVE Video
Molecular cloning and expression analysis of porcine ghrelin o-acyltransferase.
Biochem. Genet.
PUBLISHED: 04-06-2011
Show Abstract
Hide Abstract
The peptide hormone ghrelin is secreted in the stomach, with unique N-octanoylation at serine 3, which is a requirement for its functionality. These functions include growth hormone release, appetite stimulation, gastrointestinal motility, glucose regulation, and cell proliferation. The enzyme responsible for ghrelin acylation was recently identified as ghrelin O-acyltransferase (GOAT). In this study, porcine GOAT was cloned and characterized. A full-length cDNA of GOAT of 2013 bp was obtained, which included a 70-bp 5 UTR, a 635-bp 3 UTR, and a 1308-bp open reading frame encoding a protein of 415 amino acids. The GOAT and ghrelin mRNAs are co-expressed in stomach, pancreas, and duodenum at high levels. GOAT was also detected in liver, lung, brain, testis, spleen, kidney, heart, muscle, lipid, and ovary. Our results provide an important basis for further research on GOAT function and the relationship between ghrelin and GOAT.
Related JoVE Video
Cloning and expression analysis of piRNA-like RNAs: adult testis-specific small RNAs in chicken.
Mol. Cell. Biochem.
PUBLISHED: 03-26-2011
Show Abstract
Hide Abstract
Many small RNAs have been cloned from animal gonads, for example, endogenous small interfering RNAs (endo-siRNAs) were found in oocytes and piwi-interacting RNAs (piRNAs) were found in testis. Gallus gallus (chicken) is an important model organism, but few small RNAs have been identified from its gonads. In this study, we isolated and cloned 156 small RNAs from adult chicken testes. Since there is a reasonably even distribution from 22 to 33 nt, these small RNAs are slightly longer than miRNAs and endo-siRNAs. Genome mapping indicated that these small RNAs were derived from intergenic regions, exons, introns, and repetitive elements including chicken repeat 1, long terminal repeats, and simple repeats. Since they are similar with piRNAs, we named them piRNA-like RNAs (pil-RNAs). Northern blotting of 16 selected sequences showed that nine are specifically expressed in the adult testis. The vast majority of these pil-RNAs are poorly conserved between species, suggesting that they are unique to the adult chicken testis. Further analysis of the cloned pil-RNAs will improve our understanding of the function of small RNAs in animal gonad development.
Related JoVE Video
6-gingerol prevents patulin-induced genotoxicity in HepG2 cells.
Phytother Res
PUBLISHED: 01-12-2011
Show Abstract
Hide Abstract
Patulin (PAT) is a mycotoxin produced by several Penicillium, Aspergillus and Byssochlamys species. Since PAT is a potent genotoxic compound, and PAT contamination is common in fruits and fruit products, the search for newer, better agents for protection against genotoxicity of PAT is required. In this study, the chemoprotective effect of 6-gingerol against PAT-induced genotoxicity in HepG2 cells was investigated. The comet assay and micronucleus test (MNT) were used to monitor genotoxic effects. To further elucidate the underlying mechanisms, the intracellular generation of reactive oxygen species (ROS) and level of reduced glutathione (GSH) were tested. In addition, the level of oxidative DNA damage was evaluated by immunocytochemical analysis of 8-hydroxydeoxyguanosine (8-OHdG). The results showed that 6-gingerol significantly reduced the DNA strand breaks and micronuclei formation caused by PAT. Moreover, 6-gingerol effectively suppressed PAT-induced intracellular ROS formation and 8-OHdG level. The GSH depletion induced by PAT in HepG2 cells was also attenuated by 6-gingerol pretreatment. These findings suggest that 6-gingerol has a strong protective ability against the genotoxicity caused by PAT, and the antioxidant activity of 6-gingerol may play an important part in attenuating the genotoxicity of PAT.
Related JoVE Video
N-(2,3-Dimeth-oxy-benzyl-idene)naphthalen-1-amine.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 01-04-2011
Show Abstract
Hide Abstract
The title compound, C(19)H(17)NO(2), represents a trans isomer with respect to the C=N bond. The dihedral angle between the planes of the naphthyl ring system and the benzene ring is 71.70?(3)°. In the crystal, weak C-H?O hydrogen bonding is present.
Related JoVE Video
[On the relationship between serum total adiponectin and insulin resistance in polycystic ovary syndrome].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 07-24-2010
Show Abstract
Hide Abstract
It is the intent of this investigation to gain an insight into the relationship of serum total adiponectin with polycystic ovary syndrome (PCOS) and insulin resistance. Fifty-eight PCOS patients were enrolled (29 with high serum insulin level and 29 without), at the same time, 29 non-PCOS women with normal weight were included as control. The influencing factors of total adiponectin, PCOS and insulin resistance were analyzed. The serum total adiponectin of PCOS patients and all participants were found to be negatively related to waist hip ratio (r = -0.39, r = -0.36) and InHOMA-IR (r = -0.53, r = -0.45), respectively. Adiponectin was not a protective factor of PCOS (P > 0.1), but it was that of PCOS-insulin resistance (OR = 0.81; 95% CI: 0.67-0.97; P = 0.02). LH/FSH (OR = 1.51; 95% CI: 1.16-1.96; P = 0.01) and InHOMA-IR (OR = 1.26; 95% CI: 1.10-1.44; P = 0.01) were risk factors of PCOS, and waist hip ratio was that of PCOS-insulin resistance (OR = 8.57; 95% CI, 2.14-34.30, P = 0.01). Adiponectin might influence fasting insulin and InHOMA-IR (B = -0.22, P = 0.001; B = -0.02, P = 0.002). These data signify that adiponectin is not directly related with PCOS, but it is related with PCOS-HL Adiponectin might participate in the pathophysiologic mechanism of PCOS by influencing insulin sensitivity.
Related JoVE Video
Removal of Neutral Red from aqueous solution by adsorption on spent cottonseed hull substrate.
J. Hazard. Mater.
PUBLISHED: 05-29-2010
Show Abstract
Hide Abstract
Cottonseed hull, a low-cost widely available agricultural waste in China, after used as substrate for the white rot fungus Pleurotus ostreatus cultivation, was tested for the removal of Neutral Red (NR), a cationic dye, from aqueous solution. A batch adsorption study was carried out with varied solution pH, adsorbent dosage, reaction time and initial NR concentration. The results show that the kinetics of dye removal by the spent cottonseed hull substrate (SCHS) is prompt in the first 5 min and the adsorption equilibrium can be attained after 240 min. The biosorption kinetics and equilibrium follow typical pseudo-second-order and Langmuir adsorption models. Thermodynamic parameters of ?G°, ?H° and ?S° show that the adsorption is a spontaneous and endothermic process. Fourier transform infrared (FTIR) spectroscopy was used for the characterization of possible dye-biosorbent interaction. This study provides a facile method to produce low-cost biosorbent for the purification of dye contaminated water.
Related JoVE Video
[The encoding and reconstruction of parallel MRI].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 05-21-2010
Show Abstract
Hide Abstract
The advent of parallel MRI over recent years has prompted a variety of techniques for performing parallel imaging. The main distinguishing feature among these is the specific way of solving the problem of image reconstruction from undersampled multiple-coil data. The clearest distinction in this respect is that between k-space method and image-domain method. The present paper reviews the basic reconstruction approaches, aiming to emphasize the common principles along with actual differences. To this end the treatment starts with an elaboration of the encoding mechanisms and sampling strategies that define the reconstruction task. Based on these considerations, the distinction between k-space and image-domain approaches is given. At the close of this paper are presented discussioins concerning noise propagation and control in parallel imaging and an outlook upon key issues to be addressed in the future.
Related JoVE Video
The interaction between Ag+ and bovine serum albumin: a spectroscopic investigation.
Sci. Total Environ.
PUBLISHED: 04-16-2010
Show Abstract
Hide Abstract
By using spectroscopic methods, we probed the interaction of Ag(+) with bovine serum albumin (BSA) in an aqueous environment. Fluorescence of BSA quenched by Ag(+) is a dynamic quenching process. Two binding modes-a strong one at low concentration of Ag(+) and a weak one at high concentration were found. The association constant (K(A)) and the number of binding sites (n) were 4.88×10(3)M(-1) and 1.17 for strong binding, and 17.6M(-1) and 0.547 for weak binding at 293K. The results of thermodynamic parameters ?H(?), ?G(?) and ?S(?) for instinct binding modes at different temperatures indicated that the hydrogen bonding and van der Waals interaction play a major role for low Ag(+)/BSA ratio while electrostatic association for high Ag(+)/BSA ratio. Data of UV-Vis and Circular dichroism (CD) suggested that with the increasing amount of Ag(+), the secondary structure undergoes a decrease in ?-helix and an increase in ? content and the backbone of BSA experiences a micro-environmental alteration. Furthermore, the distance r between donor (Trp-212) and acceptor (Ag(+)) was evaluated to be 10nm according to nonradiative energy transfer theory.
Related JoVE Video
Production of recombinant human lysozyme in the milk of transgenic pigs.
Transgenic Res.
PUBLISHED: 03-15-2010
Show Abstract
Hide Abstract
In the swine industry pathogenic infections have a significant negative impact on neonatal survival. Piglets fed with human lysozyme, a natural antibiotic, might be more resistant to gastrointestinal infections. Here we describe the generation of transgenic swine expressing recombinant human lysozyme by somatic cell nuclear transfer. Three cloned female pigs were born, one of which expressed rhLZ at 0.32 ± 0.01 ?g/ml in milk, 50-fold higher than that of the pig native lysozyme. Both the transgenic gilts and their progeny appear healthy. Introducing human lysozyme into pigs milk has a potential to benefit the piglets by enhancing immune function and defending against pathogenic bacteria, thereby increasing the new born survival rate. This advance could be of great value to commercial swine producers.
Related JoVE Video
Angiotensin II induces C-reactive protein expression through ERK1/2 and JNK signaling in human aortic endothelial cells.
Atherosclerosis
PUBLISHED: 03-14-2010
Show Abstract
Hide Abstract
Atherosclerosis is an inflammatory disease in the vessel. As an inflammatory cytokine, C-reactive protein (CRP) participates in atherogenesis. Although angiotensin II (AngII) is known to evoke inflammatory response in vascular endothelial cells (VECs), there is no direct evidence to demonstrate the proinflammatory effect of AngII on VECs through CRP. The present study focused on effect of AngII on CRP expression and the signal pathway in human aortic endothelial cells (HAECs).
Related JoVE Video
Towards the development of a portable sensor based on a molecularly imprinted membrane for the rapid determination of salbutamol in pig urine.
Anal. Chim. Acta
PUBLISHED: 02-02-2010
Show Abstract
Hide Abstract
A new type of conductometric probe based on a molecularly imprinted membrane (MIM) for the detection of salbutamol has been designed and fabricated. The probe consists of two parallel screen-printed electrodes (SPE). One of the SPEs was coated with a molecularly imprinted membrane using salbutamol as the template, and the other was modified with a non-molecularly imprinted membrane (N-MIM). Measurements of salbutamol were conducted after the conductometric probe had been connected to a commercial portable conductometer. Multi-sample or successive detections could be easily accomplished by replacing the one-off SPE coated with the salbutamol molecularly imprinted membrane with a new one. The conductometric response of the sensor to the concentration of salbutamol displayed a linear correlation over a range from 50 to 280 nM, with a detection limit of 13.5 nM. The recoveries reached 92.1-98.3% based on pig urine samples. In addition, the sensor based on this new type of probe demonstrated high sensitivity and selectivity for salbutamol.
Related JoVE Video
Role of sp-d exchange interactions in room-temperature photoluminescence and ferromagnetism of CuCo Co-doped ZnO nanorods.
J Nanosci Nanotechnol
PUBLISHED: 11-14-2009
Show Abstract
Hide Abstract
CuCo co-doped ZnO nanorods have been synthesized via a soft chemistry route without using any surfactant, seed and catalyst. Structural analyses reveal that the samples of nominal compositions Cu0.01Co0.02Zn0.97O and Cu0.02Co0.01Zn0.97O have single hexagonal wurtzite structure without forming any extra secondary phase. Photoluminescence (PL) measurements show that the Cu co-doping in Co doped ZnO nanorods strongly influences the optical band structure and gives significant red shifts in the PL spectra. Furthermore, magnetic measurements of CuCo co-doped ZnO nanorods exhibit obvious room temperature ferromagnetism at low concentrations of Cu (< 1%) co-doping, while at higher concentrations of Cu co-doping, magnetization drops off sharply. An experimental relationship has been found to explain the redshift of E(g) edge in PL and the origin of observed ferromagnetism as function of Cu co-dopant concentration due to the spin exchange interactions between the sp band and localized spins of d electrons of dopants, which is useful for future semiconductor based spintronic devices.
Related JoVE Video
Knockdown of the prion gene expression by RNA interference in bovine fibroblast cells.
Mol. Biol. Rep.
PUBLISHED: 09-20-2009
Show Abstract
Hide Abstract
PRNP is the gene encoding prion protein whose misfolded and ?-sheet-rich isoform is the infectious agent of transmissible spongiform encephalopathy (TSE). TSE, also called prion diseases, cause fatal neurodegenerative and transmissible disorders in human and animals. Among these diseases, bovine spongiform encephalopathy (BSE) has tremendous impact on economy and human health in the world. In the present study, we hypothesize suppression of the PRNP gene expression could raise resistance to BSE in cattle by using vector-based small interfering RNA (siRNA) expression systems. Therefore, the objective was to screen effective DNA-encoding short hairpin RNAs (shRNAs) which could knockdown the PRNP gene expression in bovine fibroblast cells. Human U6 promoter was employed to drive shRNA transcription from the DNA vector, and seven shRNAs, that designed to target coding region and 3 untranslated region of the PRNP gene, were selected. Four out of seven shRNAs tested were found to be effective in inhibiting the PRNP gene expression, and the most significant suppression level was as much as 62.9% evidenced by real-time RT-PCR. Furthermore, the protein abundance was obviously reduced compared to the control. Overall, the present study demonstrated that vector-based siRNA expression systems is an efficient approach to knockdown the PRNP gene expression in bovine fibroblast cells and thereby provide donor cells for somatic cell nuclear cloning to produce cattle that is resistant to prion related diseases.
Related JoVE Video
Selecting tolerant grass seedlings and analyzing the possibility for using aged refuse as sward soil.
Ecotoxicol. Environ. Saf.
PUBLISHED: 09-15-2009
Show Abstract
Hide Abstract
In order to test the possibility for recycling use of aged refuse as sward soil, the study determined the responses of Lolium perenne L. (perennial ryegrass), Festuca arundinacea (tall fescue), and Poa annua (annual bluegrass) to its leaching. The growth of three seedlings was significantly inhibited after treatment, especially for longer treatment duration and higher concentration leaching; however, with the better growth and chlorophyll content for shorter time and lower concentration, tall fescue was more tolerant to the stress. Afterwards, several physiological responses of tall fescue were determined. For shorter treatment duration, antioxidant enzyme activities remained unchanged, and no obvious oxidative damage was observed. Prolonging exposure time, lipid peroxidation and protein oxidation occurred after treatment of higher concentration leaching, accompanying by changes of antioxidant status. It implicates that it is possible for using aged refuse as sward soil, and the critical point focused on selecting tolerant grass and controlling exposure condition.
Related JoVE Video
Efficient production of transgenic chickens based on piggyBac.
Transgenic Res.
Show Abstract
Hide Abstract
Transgenic techniques in chickens have been developed much more slowly than in mammals due to chickens unique reproduction mechanism. Retroviral methods have been the most successful. piggyBac (PB) is a transposon that has a 13 bp perfect terminal invert repeat sequence. PB can be inserted into TTAA sites and can also be precisely excised in mammals. Therefore, we have selected PB as a candidate to establish a new method to produce transgenic chickens. We constructed three donor vectors (ZGl-neo, ZGm-neo and ZGs-neo) expressing a GFP marker-gene and a neomycin resistant gene based on PB. We co-transfected each donor vector with a helper vector (CAG-PBase). We found that ZGl-neo was the most efficient PB vector. This vector could insert into TTAA sites in DF-1 cells. PB vectors were microinjected into sub-germinal cavity of newly laid eggs, and electroporation was then performed with a 20-V pulse for 5 cycles of 50 ms on and 100 ms off. GFP was expressed in different tissues of the embryos, including the gonads. Twenty-two chickens hatched after microinjection with compounds ZGl-neo and CAG-PBase (3:1). When we screened the blood DNA, 73 % (16/22) of the individuals were positive. Thirteen of the chickens grew to adulthood, 11 of which were males. 40 % (4/10) of the individuals were semen positive, and their copy numbers ranged from 0.05 to 0.21 (0.11, 0.21, 0.05, 0.06). No G1 offspring containing the integrated transposon were produced. We conclude that the PB transposon system is a novel useful tool for the efficient production of transgenic chickens.
Related JoVE Video
Surfactant-induced defects and photoluminescence of Co doped SnO2 nanorods.
J Nanosci Nanotechnol
Show Abstract
Hide Abstract
The microstructure and defect evolution of Co-doped SnO2 nanostructures have been mediated by the surfactant via a hydrothermal method. The microstructure is characterized by X-ray diffraction and Raman spectra in detail. It is found that the density of structural defects considerably increases with the increase of the surfactant amount used in the preparation process. Meanwhile, the orange emission enhances dramatically. The growth process and defect evolution have been investigated by the following time-dependent experiments. Due to the existence of hollow scrolls in the growth, the mesocrystal lamellar attachment and the rolling process are proposed for the possible growth mechanism. In the synthetic process, surfactant cations, which are incorporated into the network of the self-assembled structure, strongly interact with tin hydroxyl anions. After removing the surfactants by calcination, the vacancies create in the corresponding locations, which promote the orange emission. Our finding opens a new way to control SnO2 defects and strength the optical emission.
Related JoVE Video
Calcium regulates the cell-to-cell water flow pathway in maize roots during variable water conditions.
Plant Physiol. Biochem.
Show Abstract
Hide Abstract
Soil water shortages can decrease root hydraulic conductivity and affect Ca uptake and movement through the plant. In this study, the effects of extra Ca(2+) applied in nutrient solution on the hydraulic properties of the whole roots (Lp(r)) and cortical cells (Lp(cell)) of maize (Zea mays L.) subjected to variable water conditions were investigated. Under well-watered conditions, extra Ca(2+) significantly increased the root Ca content, total root length, and lateral root number; however, it reduced the root cortical cell volume, Lp(r), and Lp(cell). Hg(2+) inhibition experiments suggested that extra Ca(2+) could reduce the contribution of the cell-to-cell water flow pathway. Osmotic stress (10% PEG6000) significantly decreased the cortical cell volume, Lp(r), and Lp(cell) in the control plants, but smaller decreases were observed in the extra Ca(2+) plants. The Hg(2+) treatment reduced the Lp(r) larger in the extra Ca(2+) plants (74.6%) than in the control plants (53.2%), suggesting a higher contribution of the cell-to-cell pathway. The larger Hg(2+) inhibition of the Lp(cell) in the extra Ca(2+) roots (67.2%) when compared to the controls (56.4%) indicated that extra Ca(2+) can mitigate the inhibition of aquaporin expression and/or activity levels via osmotic stress. After 2 d of rehydration, the extra Ca(2+) helped the Lp(r) and Lp(cell) to recover almost completely, but these properties only partially recovered in the control plants. In conclusion, extra Ca(2+) may adjust the contribution of cell-to-cell pathway by regulating the expression and/or activity levels of AQPs according to water availability; this regulation may weaken negative effects and optimize water use.
Related JoVE Video
Directional and path-finding motion of polymer hydrogels driven by liquid mixing.
Langmuir
Show Abstract
Hide Abstract
The spreading of a miscible liquid with a low surface tension on a water surface generates the directional motion of submerged polymer hydrogels, which could be attributed to convective flows resulting from the gradient of surface tension along the surface (Marangoni effect). The direction and velocity of this motion can be well controlled by altering the driving conditions. Furthermore, a spherical hydrogel can smartly find the path to walk through a microfluidic maze when liquid mixing occurs near the maze exit. This convenient chemical driving approach to transporting submerged objects in a desired way may be useful in microfluidics, micromechanics, and other applications.
Related JoVE Video
The protective effects of hydroxytyrosol against ortho-phenylphenol-induced DNA damage in HepG2 cells.
Toxicol. Mech. Methods
Show Abstract
Hide Abstract
Ortho-phenylphenol (OPP) has been found to cause carcinomas in the urinary tract of rats. Since OPP is a potent genotoxic compound, and used as fungicides and antibacterial agents in fruits and fruit products, search for newer, better agents for protection against toxicity of OPP is required. In this study, the chemoprotective effect of hydroxytyrosol (HT) against OPP-induced DNA damage in HepG2 cells was investigated. Comet assay was used to detect the DNA damage induced by OPP. To elucidate the possible mechanisms, we tested lysosomal membrane stability, mitochondrial membrane potential, intracellular generation of reactive oxygen species (ROS), and reduced glutathione (GSH). Results showed that HT significantly reduced the DNA strand breaks caused by OPP. Moreover, HT effectively suppressed OPP-induced ROS formation, and increased the GSH level. Lysosomal membrane and mitochondrial membrane were also protected when cells were pretreated with HT. These results suggested that the disruption of lysosomal membrane integrity and the oxidative stress, leading to DNA fragmentation, may be the mechanism of DNA damage induced by OPP. The antioxidant activity of HT may play an important part in attenuating the DNA damage of OPP.
Related JoVE Video
6-Gingerol induces apoptosis through lysosomal-mitochondrial axis in human hepatoma G2 cells.
Phytother Res
Show Abstract
Hide Abstract
6-Gingerol, a major phenolic compound derived from ginger, has been known to possess anticarcinogenic activities. However, the mechanisms are not well understood. In our previous study, it was demonstrated that lysosome and mitochondria may be the primary targets for 6-gingerol in HepG2 cells. Therefore, the aim was to evaluate lysosome-mitochondria cross-signaling in 6-gingerol-induced apoptosis. Apoptosis was detected by Hoechst 33342 and TUNEL assay after 24?h treatment, and the destabilization of lysosome and mitochondria were early upstream initiating events. This study showed that cathepsin D played a crucial role in the process of apoptosis. The release of cathepsin D to the cytosol appeared to be an early event that preceded the release of cytochrome c from mitochondria. Moreover, inhibition of cathepsin D activity resulted in suppressed release of cytochrome c. To further determine the involvement of oxidative stress in 6-gingerol-induced apoptosis, the intracellular generation of reactive oxygen species (ROS) and reduced glutathione (GSH) were examined. Taken together, these results suggest that cathepsin D may be a positive mediator of 6-gingerol induced apoptosis in HepG2 cells, acting upstream of cytochrome c release, and the apoptosis may be associated with oxidative stress.
Related JoVE Video
Gold nanoparticles with asymmetric polymerase chain reaction for colorimetric detection of DNA sequence.
Anal. Chem.
Show Abstract
Hide Abstract
We developed a novel strategy for rapid colorimetric analysis of a specific DNA sequence by combining gold nanoparticles (AuNPs) with an asymmetric polymerase chain reaction (As-PCR). In the presence of the correct DNA template, the bound oligonucleotides on the surface of AuNPs selectively hybridized to form complementary sequences of single-stranded DNA (ssDNA) target generated from As-PCR. DNA hybridization resulted in self-assembly and aggregation of AuNPs, and a concomitant color change from ruby red to blue-purple occurred. This approach is simpler than previous methods, as it requires a simple mixture of the asymmetric PCR product with gold colloid conjugates. Thus, it is a convenient colorimetric method for specific nucleic acid sequence analysis with high specificity and sensitivity. Most importantly, the marked color change occurs at a picogram detection level after standing for several minutes at room temperature. Linear amplification minimizes the potential risk of PCR product cross-contamination. The efficiency to detect Bacillus anthracis in clinical samples clearly indicates the practical applicability of this approach.
Related JoVE Video
Correlation between promoter methylation of p14(ARF), TMS1/ASC, and DAPK, and p53 mutation with prognosis in cholangiocarcinoma.
World J Surg Oncol
Show Abstract
Hide Abstract
To study the methylation status of genes that play a role in the p53-Bax mitochondrial apoptosis pathway and its clinical significance in cholangiocarcinoma.
Related JoVE Video

What is Visualize?

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

How does it work?

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

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

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