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Find video protocols related to scientific articles indexed in Pubmed.
Correlations among ocular surface temperature difference value, the tear meniscus height, Schirmer's test and fluorescein tear film break up time.
Br J Ophthalmol
PUBLISHED: 10-10-2014
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To report the use of a thermographer for measuring ocular surface temperature, and to evaluate the correlation among the obtained temperature difference values (TDVs) and dry eye parameters (tear meniscus height (TMH); Schirmer's test results; fluorescent tear breakup time (FTBUT)).
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Insights into the programmed ketoreduction of partially reducing polyketide synthases: stereo- and substrate-specificity of the ketoreductase domain.
Org. Biomol. Chem.
PUBLISHED: 09-20-2014
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One of the hallmarks of iterative polyketide synthases (PKSs) is the programming mechanism which is essential for the generation of structurally diverse polyketide products. In partially reducing iterative PKSs (PR-PKSs), the programming mechanism is mainly dictated by the ketoreductase (KR) domain. The KR domain contributes to the programming of PR-PKSs through selective reduction of polyketide intermediates. How the KR domain achieves the selective ketoreduction remains to be fully understood. In this study, we found that the KR domain of the (R)-mellein-synthesizing PR-PKS SACE5532 functions as a B-type KR domain to generate (R)-hydroxyl functionalities. Comparative studies of the KR domains of SACE5532 and NcsB suggested that the two KR domains have distinct substrate preferences towards simple N-acetylcysteamine thioester (SNAC) substrates. We further found that the substrate preference of KRSACE5532 can be switched by swapping several motifs with KRNcsB, and that swapping of the same motifs in the full length SACE5532 resulted in a reprogramming of the PKS. Together, the results advance our understanding of the programming of iterative PR-PKSs by providing new support to the hypothesis that the programmed ketoreduction is accomplished by differential recognition of polyketide intermediates.
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Functional electrical stimulation-facilitated proliferation and regeneration of neural precursor cells in the brains of rats with cerebral infarction.
Neural Regen Res
PUBLISHED: 09-11-2014
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Previous studies have shown that proliferation of endogenous neural precursor cells cannot alone compensate for the damage to neurons and axons. From the perspective of neural plasticity, we observed the effects of functional electrical stimulation treatment on endogenous neural precursor cell proliferation and expression of basic fibroblast growth factor and epidermal growth factor in the rat brain on the infarct side. Functional electrical stimulation was performed in rat models of acute middle cerebral artery occlusion. Simultaneously, we set up a placebo stimulation group and a sham-operated group. Immunohistochemical staining showed that, at 7 and 14 days, compared with the placebo group, the numbers of nestin (a neural precursor cell marker)-positive cells in the subgranular zone and subventricular zone were increased in the functional electrical stimulation treatment group. Western blot assays and reverse-transcription PCR showed that total protein levels and gene expression of epidermal growth factor and basic fibroblast growth factor were also upregulated on the infarct side. Prehensile traction test results showed that, at 14 days, prehension function of rats in the functional electrical stimulation group was significantly better than in the placebo group. These results suggest that functional electrical stimulation can promote endogenous neural precursor cell proliferation in the brains of acute cerebral infarction rats, enhance expression of basic fibroblast growth factor and epidermal growth factor, and improve the motor function of rats.
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Establishment of an enzyme-linked immunosorbent assay and application on determination of ginsenoside Re in human saliva.
Planta Med.
PUBLISHED: 09-08-2014
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This work describes an immunochemical approach for the quality control of Panax ginseng and a pharmacological study of ginsenoside Re, a major bioactive constituent in P. ginseng, using an enzyme-linked immunosorbent assay. A hybridoma secreting monoclonal antibody against ginsenoside Re was produced by fusing splenocytes immunized with a ginsenoside Re-bovine serum albumin conjugate with the hypoxanthine-aminopterin-thymidine-sensitive mouse myeloma SP2/0 cell line. The method, at an effective measuring range of 7.8-500 ng?·?mL(-1) of ginsenoside Re, successfully detected ginsenoside Re in Chinese traditional herb prescriptions. The results demonstrate that we generated a novel and reliable assay system for measuring ginsenoside Re in Chinese medicines more efficiently. Futhermore, we determined the ginsenoside Re concentrations in the saliva of six healthy adults after the oral administration of a ginseng capsule to study the pharmacokinetics of ginsenoside Re in human saliva.
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The Notch ?-secretase inhibitor ameliorates kidney fibrosis via inhibition of TGF-?/Smad2/3 signaling pathway activation.
Int. J. Biochem. Cell Biol.
PUBLISHED: 08-20-2014
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Kidney fibrosis is a common feature of chronic kidney disease (CKD). A recent study suggests that abnormal Notch signaling activation contributes to the development of renal fibrosis. However, the molecular mechanism that regulates this process remains unexplored. Unilateral ureteral obstruction (UUO) or sham-operated C57BL6 mice (aged 10 weeks) were randomly assigned to receive dibenzazepine (DBZ, 250?g/100g/d) or vehicle for 7 days. Histologic examinations were performed on the kidneys using Masson's trichrome staining and immunohistochemistry. Real-time PCR and western blot analysis were used for detection of mRNA expression and protein phosphorylation. The expression of Notch 1, 3, and 4, Notch intracellular domain (NICD), and its target genes Hes1 and HeyL were upregulated in UUO mice, while the increase in NICD protein was significantly attenuated by DBZ. After 7 days, the severity of renal fibrosis and expression of fibrotic markers, including collagen 1?1/3?1, fibronectin, and ?-smooth muscle actin, were markedly increased in UUO compared with sham mice. In contrast, administration of DBZ markedly attenuated these effects. Furthermore, DBZ significantly inhibited UUO-induced expression of transforming growth factor (TGF)-?, phosphorylated Smad 2, and Smad 3. Mechanistically, Notch signaling activation in tubular epithelial cells enhanced fibroblast proliferation and activation in a coculture experiment. Our study provides evidence that Notch signaling is implicated in renal fibrogenesis. The Notch inhibitor DBZ can ameliorate this process via inhibition of the TGF-?/Smad2/3 signaling pathway, and might be a novel drug for preventing chronic kidney disease.
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Combined effects of leukocyte telomere length, p53 polymorphism and human papillomavirus infection on esophageal squamous cell carcinoma in a Han Chinese population.
Cancer Epidemiol
PUBLISHED: 08-18-2014
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Telomere shortening has been suggested to be a genetic predictor for various cancers. However, evidences about this point with respect to esophageal squamous cell carcinoma (ESCC) in Han Chinese populations remain limited. Our previous study demonstrated that p53 Arg72Pro polymorphism was associated with the risk of human papillomavirus (HPV)-related ESCC. Telomeres and p53 play important roles in maintaining genomic stability and regulating the cell cycle. HPV impacts both telomere length stabilization and p53 degradation. Given the roles of the three factors, we evaluated leukocyte telomere length, p53 variants and HPV-16 serology to examine the potential associations between them and ESCC risk in a case-control study with 308 patients and 309 cancer-free controls matched by age and sex. Compared with long telomere length, short telomere length was significantly associated with an increased risk of ESCC (adjusted OR 2.01; 95% CI 1.41-2.80). Moreover, this association was enhanced when combined with HPV-16 seropositivity and p53 Arg/Arg or Arg/Pro genotypes. Notably, individuals with short telomere length, Arg/Pro or Arg/Arg genotypes and HPV-16 seropositivity had a 12.08-fold (95% CI 5.49-26.56) increased risk of ESCC compared to those with none of the three investigated risk factors. Taken together, these results indicate that short telomere length in peripheral blood leukocytes is a biomarker for ESCC risk, and has statistically additive effects with p53 variants and HPV seropositivity with regard to the risk of ESCC in a Han Chinese population.
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Regulating drug release from pH- and temperature-responsive electrospun CTS-g-PNIPAAm/poly(ethylene oxide) hydrogel nanofibers.
Biomed Mater
PUBLISHED: 08-18-2014
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Temperature- and pH-responsive polymers have been widely investigated as smart drug release systems. However, dual-sensitive polymers in the form of nanofibers, which is advantageous in achieving rapid transfer of stimulus to the smart polymeric structures for regulating drug release behavior, have rarely been explored. In this study, chitosan-graft-poly(N-isopropylacrylamide) (CTS-g-PNIPAAm) copolymer was synthesized by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxy succinimide (NHS) as grafting agents to graft carboxyl-terminated PNIPAAm (PNIPAAm-COOH) chains onto the CTS biomacromolecules, and then CTS-g-PNIPAAm with or without bovine serum albumin (BSA) was fabricated into nanofibers through electrospinning using poly(ethylene oxide) (PEO, 10 wt%) as a fiber-forming facilitating additive. The BSA laden CTS-g-PNIPAAm/PEO hydrogel nanofibers were tested to determine their drug release profiles by varying pH and temperature. Finally, cytotoxicity of the CTS-g-PNIPAAm/PEO hydrogel nanofibers was evaluated by assaying the L929 cell proliferation using the MTT method. It was found that the synthesized CTS-g-PNIPAAm possessed a temperature-induced phase transition and lower critical solution temperature (LCST) at 32°?C in aqueous solutions. The rate of BSA release could be well modulated by altering the environmental pH and temperature of the hydrogel nanofibers. The CTS-g-PNIPAAm/PEO hydrogel nanofibers supported L929 cell growth, indicative of appropriate cytocompatibility. Our current work could pave the way towards developing multi-stimuli responsive nanofibrous smart materials for potential applications in the fields of drug delivery and tissue engineering.
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Optimization of the condition for adsorption of gallic acid by Aspergillus oryzae mycelia using Box-Behnken design.
Environ Sci Pollut Res Int
PUBLISHED: 08-12-2014
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Fresh biomass of Aspergillus oryzae (A. oryzae) CGMCC5992 can effectively remove gallic acid from aqueous solution. To improve the removal rate of gallic acid, this study first identified the important factors affecting the removal rate of gallic acid with univariate analysis, and then used four-factor and three-level Box-Behnken design (BBD) with the removal rate of gallic acid as response value, to obtain the optimum conditions for the removal of gallic acid as follows: 6.95 h treatment time, pH 3.70, 7.07 g/L mycelium volume, and 120.64 mg/L initial concentration of gallic acid. Under such optimized condition, the removal rate of gallic acid approached 99.21 %. HPLC-MS analysis proved that the gallic acid in aqueous solution was completely removed by A. oryzae, rather than being metabolized into its derivatives. Scanning electron microscopy (SEM) indicated that the biomass morphology and surface structure of A. oryzae changed after the adsorption of gallic acid. Thus, the present study has provided an optimal condition for A. oryzae removal of gallic acid in water.
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Simultaneous measurements of cortisol and cortisone in urine and hair for the assessment of 11?-hydroxysteroid dehydrogenase activity among methadone maintenance treatment patients with LC-ESI-MS/MS.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-10-2014
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The activity of 11?-hydroxysteroid dehydrogenases (11?-HSD) is traditionally assessed using the ratio of cortisol to cortisone in urine or saliva. However, these biomarkers only reflect the local activity of 11?-HSD, and are easily affected by circadian variation of cortisol secretion. The shortcomings might be overcome by hair analysis. The present study aimed to develop an enhanced assay for simultaneous measurements of cortisol and cortisone in both hair and urine samples. The samples were collected from 29 patients under methadone maintenance treatment. The cortisol and cortisone were extracted either by solid phase extraction from a 20-mg milled hair sample after a 14-h incubation in 1ml of methanol, or by twice liquid-liquid extraction from a 20-fold diluted urine sample. The analyses were performed using high performance liquid chromatography tandem mass spectrometry with electrospray ionization in negative mode. Limits of detection and quantification were 0.5 and 1.25pg/mg for hair steroids and 0.2 and 0.5ng/ml for urinary steroids, respectively. The recoveries were more than 97%. The intra- and inter-day coefficients of variation were less than 10%. The ratios of cortisol to cortisone in hair and urine were both less than one, but did not correlate with each other. A possible reason for the lack of correlation was that the ratios in hair and urine might mostly reflect the activity of 11?-HSD type 2 in the eccrine sweat gland and in the kidney, respectively. Additionally, a significant correlation was observed between results obtained using external standard quantification and internal standard quantification.
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A comparative study on the degradation of gallic acid by Aspergillus oryzae and Phanerochaete chrysosporium.
Water Sci. Technol.
PUBLISHED: 07-16-2014
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Recently, as an emerging persistent dissolved organic pollutant (DOP), gallic acid (GA) and its efficient decomposition methods have received global attention. The present work aimed to compare the effect of Aspergillus oryzae 5992 and Phanerochaete chrysosporium 40719 on degradation of different concentrations of GA. The A. oryzae grew well and achieved a GA removal rate up to 99% in media containing 1-4% GA, much higher than P. chrysosporium. The activity of laccase and lignin peroxidase excreted by A. oryzae was higher than that by P. chrysosporium in the presence of GA. Based on the results of high-performance liquid chromatography-electrospray ionization-mass spectrometry, three relevant intermediate metabolites were determined as progallin A, methyl gallate, and pyrogallic acid, implying that A. oryzae could not degrade GA unless the carboxyl in the molecule was protected or removed. In view of the ability of A. oryzae to accommodate a high concentration of GA and achieve a high removal rate, as well as the significantly different enzyme activities involved in GA degradation and the underlying mechanisms between the two fungal strains, A. oryzae is proven to be a superior strain for the degradation of DOP.
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Direct observation and validation of fluorescein tear film break-up patterns by using a dual thermal-fluorescent imaging system.
Biomed Opt Express
PUBLISHED: 07-14-2014
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The fluorescein tear film break-up test is a common tear film stability test for dry eye diagnosis. This test requires applying fluorescein sodium drops to a tear film to observe the tear film break-up. However, this test is limited by using the fluorescein sodium drops, which can induce reflex tearing and reduce the reliability of the diagnosis results. This paper proposes that tear film evaporation accelerates on the fluorescein tear film break-up area (FTBA), resulting in a lower temperature area (LTA) on the tear film. A dual modality system was established to capture the thermal and fluorescent image of fluorescein-stain tear films for 48 participants. Observations showed that the LTA and FTBA were highly correlated in their location (r = 0.82) and size (r = 0.91). This is first study to show that the FTBA and LTA are essentially the same region. This study demonstrated the feasibility of using the noncontact thermograph method to evaluate tear film stability without using a fluorescein sodium drop.
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The effectiveness of functional electrical stimulation based on a normal gait pattern on subjects with early stroke: a randomized controlled trial.
Biomed Res Int
PUBLISHED: 07-10-2014
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To investigate the effectiveness of four-channel FES based on a normal gait pattern on improving functional ability in subjects early after ischemic stroke.
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HPV seropositivity joints with susceptibility loci identified in GWASs at apoptosis associated genes to increase the risk of Esophageal Squamous Cell Carcinoma (ESCC).
BMC Cancer
PUBLISHED: 06-30-2014
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We previously showed that human papillomavirus (HPV) serostatus was not an independent risk factor for esophageal squamous cell carcinoma(ESCC) in nonsmokers and nondrinkers; however, HPV increased the risk in smokers.
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EGR1 decreases the malignancy of human non-small cell lung carcinoma by regulating KRT18 expression.
Sci Rep
PUBLISHED: 06-03-2014
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Early growth response 1 (EGR1) is a multifunctional transcription factor; Positive and negative functions of EGR1 in various tumors rely on the integrated functions of various genes it regulates. In this study, we observed the role of EGR1 in non-small-cell lung carcinoma (NSCLC) and identified genes that influence cell fate and tumor development. Various assays showed that EGR1 arrested cell mobility, inhibited migration, and induced apoptosis. Microarray analysis revealed that 100 genes, including CDKN1C, CDC27 and PRKDC, changed their mRNA expressions with the increase of EGR1 and contributed to intervention of tumor progression. Bioinformatics analysis and promoter analysis indicated that an EGR1 binding site was situated in the promoter of KRT18 (also named CK18) and KRT18 could assist in inhibition of NSCLC development. The expression level of EGR1 and KRT18 in NSCLC clinical cases was investigated by immunohistochemistry, in which the protein expression of KRT18 was found to be significantly associated with EGR1 and lymph node metastasis. The results collectively confirm that EGR1 functions as a tumor suppressor in NSCLC. This study is the first to report KRT18 expression is directly regulated by EGR1, and contributes to decrease malignancy of NSCLC.
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N?Myc downstream?regulated gene 2 suppresses proliferation and induces oncosis of OS?RC?2 human renal cancer cells.
Mol Med Rep
PUBLISHED: 05-30-2014
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V?myc avian myelocytomatosis viral oncogene homolog (Myc) regulates cell proliferation, differentiation and apoptosis in several types of cancer. N?myc downstream?regulated gene 2 (NDRG2) is known to exhibit reduced expression in renal cell carcinoma (RCC) tissues compared with adjacent non?neoplastic tissues and is an independent poor prognostic factor predicting survival in RCC. In the present study, green fluorescent protein (GFP)?NDRG2 and control GFP recombinant adenovirus plasmids were constructed and used to infect human renal cancer (OS?RC?2) cells. NDRG2 expression was measured using western blot analysis and the subcellular localization of NDRG2 was detected using confocal microscopy. The rate of proliferation of the cells was measured using colony formation and MTT assays, and the cell cycle was analyzed using flow cytometry. The results showed that the OS?RC?2 cells expressed little NDRG2 prior to infection with GFP?NDRG2 recombinant adenovirus; however, following infection, NDRG2 was found to be overexpressed, primarily in the mitochondria. The proliferation rate of the OS?RC?2 cells was reduced by NDRG2. Approximately 84.8% of the NDRG2?expressing cells were in S phase compared with 58.7% in the control virus?infected cells (P<0.05). In addition, the upregulation of NDRG2 induced a higher proportion of OS?RC?2 cells to undergo oncosis instead of apoptosis. In conclusion, the results from this study suggest that NDRG2 expressed in mitochondria may arrest renal cancer cells in S phase, decrease cell proliferation and induce oncosis. This indicates that NDRG2 is not only a biomarker, but may also be a therapeutic target for the treatment of RCC.
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[Outcomes of percutaneous coronary intervention for intermediate coronary artery disease guided by intravascular ultrasound or fractional flow reserve].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 05-23-2014
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To evaluate the long-term clinical outcomes of fractional flow reserve (FFR)-guided versus intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) for intermediate coronary lesions.
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Adenovirus-mediated NDRG2 inhibits the proliferation of human renal cell carcinoma cell line OS-RC-2 in vitro.
Cell Biochem. Biophys.
PUBLISHED: 05-20-2014
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The objective of the study is to investigate the inhibitory effects of adenovirus-mediated N-Myc downstream-regulated gene 2 (NDRG2) on the proliferation of human renal cell carcinoma cell line OS-RC-2 in vitro. NDRG2 was harvested by RT-PCR, confirmed by DNA sequencing, and then cloned into the eukaryotic expression vector pIRES2-EGFP, which encodes green fluorescent protein (GFP), to construct pIRES2-EGFP-NDRG2 plasmid. OS-RC-2 cells with NDRG2 negative expression were transfected with pIRES2-EGFP-NDRG2 plasmid. The growth of transfected OS-RC-2 cells was observed under the light and fluorescence microscopes. After colony-forming cell assays, cell proliferation detection, and MTT assays, the growth curves of cells in each group were plotted to investigate the inhibitory effects of adenovirus-mediated NDRG2 on the proliferation of OS-RC-2 cells. Cell cycle was determined by flow cytometry. Confocal laser scanning microscopy was applied to determine the specific location of NDRG2 protein in subcellular level. A eukaryotic expression vector pIRES2-EGFP-NDRG2 was successfully constructed. After NDRG2 transfection, the growth of OS-RC-2 cells was inhibited. Flow cytometry showed that cells were arrested in S phase but the peak of cell apoptosis was not present, and confocal laser scanning microscopy showed that NDRG2 protein was located in mitochondrion. In conclusion, NDRG2 can significantly inhibit the proliferation of OS-RC-2 cells in vitro and its protein is specifically expressed in the mitochondrion.
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Inhibition of TRPM7 channels reduces degranulation and release of cytokines in rat bone marrow-derived mast cells.
Int J Mol Sci
PUBLISHED: 05-18-2014
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mast cells play an important role in airway inflammation in asthma. The transient receptor potential melastatin-like 7 (TRPM7) channel is expressed in primary human lung mast cells and plays a critical role for cell survival. This study aimed to investigate the role of TRPM7 on degranulation and release of cytokines in rat bone marrow-derived mast cells (BMMCs).
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Kinetic measurements of hand motor impairments after mild to moderate stroke using grip control tasks.
J Neuroeng Rehabil
PUBLISHED: 04-30-2014
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The aim of this study is to investigate quantitative outcome measurements of hand motor performance for subjects after mild to moderate stroke using grip control tasks and characterize abnormal flexion synergy of upper extremities after stroke.
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[Expression of stromal cell-derived factor-1 in endometriosis by steroid receptor coactivatorson steroid hormone].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 04-18-2014
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To study the expression patterns of steroid receptor coactivators (SRC) and steroid-induced stromal cell-derived factor-1 (SDF-1) in endometriosis, and to explore the roles of SRC in the steroid-induced SDF-1 expression endometriosis.
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Complement 5a receptor mediates angiotensin II-induced cardiac inflammation and remodeling.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 04-17-2014
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Inflammation contributes to hypertension-induced cardiac damage and fibrotic remodeling. Complement activation produces anaphylatoxins, which are major inflammatory effectors. Here, we investigated the role of complement anaphylatoxins in angiotensin II (Ang II)-induced cardiac remodeling.
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CHIP is a novel tumor suppressor in pancreatic cancer through targeting EGFR.
Oncotarget
PUBLISHED: 04-12-2014
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Carboxyl terminus of heat shock protein 70-interacting protein (CHIP) is an E3 ubiquitin ligase that is involved in protein quality control and mediates several tumor-related proteins in many cancers, but the function of CHIP in pancreatic cancer is not known. Here we show that CHIP interacts and ubiquitinates epidermal growth factor receptor (EGFR) for proteasome-mediated degradation in pancreatic cancer cells, thereby inhibiting the activation of EGFR downstream pathway. CHIP suppressed cell proliferation, anchor-independent growth, invasion and migration, as well as enhanced apoptosis induced by erlotinib in vitro and in vivo. The expression of CHIP was decreased in pancreatic cancer tissues or sera. Low CHIP expression in tumor tissues was correlated with tumor differentiation and shorter overall survival. These observations indicate that CHIP serves as a novel tumor suppressor by down-regulating EGFR pathway in pancreatic cancer cells, decreased expression of CHIP was associated with poor prognosis in pancreatic cancer.
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S100a8/a9 released by CD11b+Gr1+ neutrophils activates cardiac fibroblasts to initiate angiotensin II-Induced cardiac inflammation and injury.
Hypertension
PUBLISHED: 04-07-2014
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Angiotensin II induces cardiovascular injury, in part, by activating inflammatory response; however, the initial factors that trigger the inflammatory cascade remain unclear. Microarray analysis of cardiac tissue exposed to systemic angiotensin II infusion revealed that extracellular heterodimeric proteins S100a8/a9 were highly upregulated. The increase in S100a8/a9 mRNA of CD11b(+)Gr1(+) neutrophils isolated from both the peripheral blood and heart was highest on day 1 of angiotensin II infusion and decreased to baseline at day 7. Immunostaining showed that S100a8/a9 was primarily present in infiltrating CD11b(+)Gr1(+) neutrophils in the heart. The receptor for advanced glycation end products, an S100a8/a9 receptor, was expressed in cardiac fibroblasts (CFs). Microarray analysis and Bio-Plex protein array showed that treatment of CFs with recombinant S100a8/a9 activated multiple chemokine and cytokines released. Luciferase reporter assay indicated S100a8/a9-activated nuclear factor-? B pathway in CFs. Consequently, recombinant S100a8/a9-treated CFs promoted migration of monocytes and CFs, whereas neutralizing S100a9 antibody blocked S100a9 or receptor for advanced glycation end products-suppressed cellular migration. Finally, administration of a neutralizing S100a9 antibody prevented angiotensin II infusion-induced nuclear factor-? B activation, inflammatory cell infiltration, cytokine production, subsequent perivascular and interstitial fibrosis, and hypertrophy in heart. Our findings identify neutrophil-produced S100a8/a9 as an initial proinflammatory factor needed to trigger inflammation and cardiac injury during acute hypertension.
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One-step shell polymerization of inorganic nanoparticles and their applications in SERS/nonlinear optical imaging, drug delivery, and catalysis.
Sci Rep
PUBLISHED: 03-26-2014
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Surface functionalized nanoparticles have found their applications in several fields including biophotonics, nanobiomedicine, biosensing, drug delivery, and catalysis. Quite often, the nanoparticle surfaces must be post-coated with organic or inorganic layers during the synthesis before use. This work reports a generally one-pot synthesis method for the preparation of various inorganic-organic core-shell nanostructures (Au@polymer, Ag@polymer, Cu@polymer, Fe3O4@polymer, and TiO2@polymer), which led to new optical, magnetic, and catalytic applications. This green synthesis involved reacting inorganic precursors and poly(styrene-alt-maleic acid). The polystyrene blocks separated from the external aqueous environment acting as a hydrophobic depot for aromatic drugs and thus illustrated the integration of functional nanoobjects for drug delivery. Among these nanocomposites, the Au@polymer nanoparticles with good biocompatibility exhibited shell-dependent signal enhancement in the surface plasmon resonance shift, nonlinear fluorescence, and surface-enhanced Raman scattering properties. These unique optical properties were used for dual-modality imaging on the delivery of the aromatic photosensitizer for photodynamic therapy to HeLa cells.
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Depression and anxiety in cancer patients in a Tertiary General Hospital in Singapore.
Asian J Psychiatr
PUBLISHED: 03-25-2014
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Past research has indicated that distress, anxiety and depression may occur in cancer patients during the course of their illness and treatment.
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Identifying halophilic proteins based on random forests with preprocessing of the pseudo-amino acid composition.
J. Theor. Biol.
PUBLISHED: 03-21-2014
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Proteins from the "salt-out" halophiles are very different with those from the "salt-in" halophiles and the non-halophiles. We chose an ensemble classifier named random forests to discriminate the three kinds of proteins depending on their primary sequences. When extracting the sequence information with the pseudo-amino acid composition, the overall accuracy of the 10-fold cross-validation was 81.1% with the optimal parameters of random forest selected by the uniform design method. By preprocessing of the raw pseudo-amino acid composition with a supervised resampling method, the overall accuracy increased 11.5% and achieved 92.6%. Random forests outperformed other ensemble algorithms and support vector machine. To validate the preprocessing step, we selected other four feature extracting methods and compared the success rates before and after preprocessing with random forest and k-nearest neighbor. The improvement of the success rates ranged from 10.9% to 15.9%, suggesting the preprocessing of the raw data is effective and should get more extensive application in extracting the features of protein sequences.
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Growth factors have a protective effect on neomycin-induced hair cell loss.
Cell Biol. Int.
PUBLISHED: 03-14-2014
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We have demonstrated that selected growth factors are involved in regulating survival and proliferation of progenitor cells derived from the neonatal rat organ of Corti (OC). The protective and regenerative effects of these defined growth factors on the injured organ of Corti were therefore investigated. The organ of Corti dissected from the Wistar rat pups (P3-P5) was split into apical, middle, and basal parts, explanted and cultured with or without neomycin and growth factors. Insulin-like growth factor-1 (IGF-1), fibroblast growth factor-2 (FGF-2), and epidermal growth factor (EGF) protected the inner hair cells (IHCs) and outer hair cells (OHCs) from neomycin ototoxicity. Using EGF, IGF-1, and FGF-2 alone induced no protective effect on the survival of auditory hair cells. Combining 2 growth factors (EGF?+?IGF-1, EGF?+?FGF-2, or IGF-1?+?FGF-2) gave statistically protective effects. Similarly, combining all three growth factors effectively protected auditory hair cells from the ototoxic insult. None of the growth factors induced regeneration of hair cells in the explants injured with neomycin. Thus various combinations of the three defined factors (IGF-1, FGF-2, and EGF) can protect the auditory hair cells from the neomycin-induced ototoxic damage, but no regeneration was seen. This offers a possible novel approach to the treatment of hearing loss.
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The requirement of CD8+ T cells to initiate and augment acute cardiac inflammatory response to high blood pressure.
J. Immunol.
PUBLISHED: 03-05-2014
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Macrophage infiltration and activation in myocardium are hallmarks of acute cardiac inflammatory response to high blood pressure. However, the underlying mechanisms remain elusive. In this article, we report that CD8(+) T cells are required for cardiac recruitment and activation of macrophages. First, mice with CD8 gene-targeted (CD8 knockout) or CD8(+) T cells depleted by Ab showed significantly reduced cardiac inflammatory response to the elevation of blood pressure after angiotensin II (Ang II) infusion, whereas CD8 knockout mice reconstituted with CD8(+) T cells restored the sensitivity to Ang II. More importantly, CD8(+) T cells were required for macrophage infiltration in myocardium and subsequent activation to express proinflammatory cytokines and chemokines. Furthermore, macrophage activation required direct contact with activated CD8(+) T cells, but with TCR dispensable. TCR-independent activation of macrophages was further confirmed in MHC class I-restricted OVA-specific TCR transgenic mice, which showed a CD8(+) T cell activation and cardiac proinflammatory response to Ang II similar to that of wild-type mice. Finally, only myocardium-infiltrated, but not peripheral, CD8(+) T cells were specifically activated by Ang II, possibly by the cardiac IFN-? that drove IFN-?R(+) CD8(+) T cell infiltration and activation. Thus, this work identified a TCR-independent innate nature of CD8(+) T cells that was critical in initiating the sterile immune response to acute elevation of blood pressure.
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Assessment of baicalin in mouse blood by monoclonal antibody-based icELISA.
Biomed. Chromatogr.
PUBLISHED: 02-27-2014
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An indirect competitive enzyme-linked immunosorbent assay (icELISA) based on monoclonal antibaodies (MAb) was recently developed. This new method displays high sensitivity and accuracy, and is especially suitable for pharmacokinetic studies in small laboratory animals. This study aimed to develop an icELISA procedure for baicalin (BAL) quantitation in blood. We successfully developed the icELISA and applied in pharmacokinetic assays of Gegen Qinlian Decoction in mice. A linear correlation was obtained for BAL concentrations in the range from 34.69 to 2220.00?µg/L. The regression equation was y?=?1.5557?-?0.4028log(C) with a correlation coefficient of 0.9936. Precision and accuracy of the icELISA method were evaluated by the variations between replicates from well to well (intra-assay) and plate to plate (inter-assay). The values obtained for these parameters were within the normal range (<15%). The recovery rates ranged from 98.93 to 126.78%, meeting the requirements for biological samples. Stability studies showed that BAL sample solutions were intact for 1?h, enough time for UV detection. However, long-term storage and especially freeze-thaw procedures were detrimental to BAL. The pharmacokinetic parameters derived from mouse experiments were as follows: area under the curves from time 0 to 48?h, 1876.15?±?1108.14?mg?h/L; mean maximum blood concentrations, 101.09?±?31.53?mg/L; time of maximum concentration, 3.58?±?2.88?h; mean residence time, 79.30?±?61.21?h. Copyright © 2014 John Wiley & Sons, Ltd.
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Temporal features of elevated hair cortisol among earthquake survivors.
Psychophysiology
PUBLISHED: 02-24-2014
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This study aimed to determine the effect on hair cortisol level of a chronic stress response from the Wenchuan earthquake, and to explore the temporal features of elevated hair cortisol. We recruited two cohorts of earthquake survivors: cohort A consisted of 12 male adults and 8 females and cohort B of 20 male adolescents, with 23 and 29 participants as controls, respectively. Their hair samples closest to the scalp were assayed with mass spectrometry to determine cortisol content. Results revealed that hair cortisol content in survivors of cohort A was significantly higher than in the control. For survivors of cohort B, hair cortisol levels increased 6 and 22 weeks after the earthquake and decreased 43 weeks after the outburst. In conclusion, the chronic stress response elicited by the earthquake resulted in elevated hair cortisol. Timing since the earthquake outburst played an important role in the long-term response of the HPA axis to a major acute stressor.
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Electrospun biomimetic fibrous scaffold from shape memory polymer of PDLLA-co-TMC for bone tissue engineering.
ACS Appl Mater Interfaces
PUBLISHED: 02-07-2014
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Multifunctional fibrous scaffolds, which combine the capabilities of biomimicry to the native tissue architecture and shape memory effect (SME), are highly promising for the realization of functional tissue-engineered products with minimally invasive surgical implantation possibility. In this study, fibrous scaffolds of biodegradable poly(d,l-lactide-co-trimethylene carbonate) (denoted as PDLLA-co-TMC, or PLMC) with shape memory properties were fabricated by electrospinning. Morphology, thermal and mechanical properties as well as SME of the resultant fibrous structure were characterized using different techniques. And rat calvarial osteoblasts were cultured on the fibrous PLMC scaffolds to assess their suitability for bone tissue engineering. It is found that by varying the monomer ratio of DLLA:TMC from 5:5 to 9:1, fineness of the resultant PLMC fibers was attenuated from ca. 1500 down to 680 nm. This also allowed for readily modulating the glass transition temperature Tg (i.e., the switching temperature for actuating shape recovery) of the fibrous PLMC to fall between 19.2 and 44.2 °C, a temperature range relevant for biomedical applications in the human body. The PLMC fibers exhibited excellent shape memory properties with shape recovery ratios of Rr > 94% and shape fixity ratios of Rf > 98%, and macroscopically demonstrated a fast shape recovery (?10 s at 39 °C) in the pre-deformed configurations. Biological assay results corroborated that the fibrous PLMC scaffolds were cytocompatible by supporting osteoblast adhesion and proliferation, and functionally promoted biomineralization-relevant alkaline phosphatase expression and mineral deposition. We envision the wide applicability of using the SME-capable biomimetic scaffolds for achieving enhanced efficacy in repairing various bone defects (e.g., as implants for healing bone screw holes or as barrier membranes for guided bone regeneration).
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Development of an enzyme-linked immunosorbent assay based on anti-puerarin monoclonal antibody and its applications.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-26-2014
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An enzyme-linked immunosorbent assay (ELISA) was developed, and its application in immunoaffinity column chromatography was studied using a monoclonal antibody (MAb) against puerarin. Splenocytes isolated from a female BALB/c mouse immunised with a puerarin-bovine serum albumin (BSA) conjugate were fused with SP2/0 myeloma cells. The hybridoma cell line secreting MAb against puerarin (AA9) was acquired by screening and limiting dilution. The antibody generated was highly specific for puerarin with <0.01% cross-reactivity with over 50 structurally related chemicals, except for baicalein (51.8%). Using AA9, we developed an immunoassay for puerarin with a linear detection range of 10ng/ml to 1?g/ml. This assay system was further validated using intra- and inter-assays and recovery experiments. In addition, puerarin levels in both formulated Chinese medicines and biological samples were determined with high sensitivity and efficiency. Finally, we developed and validated protocols for knocking puerarin out of its parent medicine completely. In conclusion, we successfully developed a reliable ELISA and an immunoaffinity column for puerarin detection and knockout, which are useful tools for exploring the role of puerarin in formulated Chinese medicines.
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The association between 5-HTTLPR gene polymorphism and behavioral inhibition in Chinese toddlers.
Dev Psychobiol
PUBLISHED: 01-23-2014
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As one of the fundamental individual characteristics, behavioral inhibition in early childhood has considerable implications for the development of social, cognitive, and psychological adjustment. The purpose of this study was to examine the relation between the 5-HTTLPR polymorphism and behavioral inhibition in Chinese children using a cross-sectional design. A sample of 263 2-year-old children (134 boys and 129 girls of Han ethnicity; ages ranging from 24 to 26 months) in China participated in the study. Behavioral inhibition was assessed through laboratory observations, and genomic DNA was collected with buccal swabs. The results of analysis of covariance (ANCOVA) indicated that the homozygous short 5-HTTLPR allele was associated with lower levels of behavioral inhibition, which was different from most of the findings based on individuals in Western countries. The results suggest that social and cultural factors may be involved in shaping links between the 5-HTTLPR polymorphism and children's specific behaviors. © 2014 Wiley Periodicals, Inc. Dev Psychobiol 56: 1601-1608, 2014.
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Relationship between effort-reward imbalance and hair cortisol concentration in female kindergarten teachers.
J Psychosom Res
PUBLISHED: 01-20-2014
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The present study aims to investigate the relationship between effort-reward imbalance and hair cortisol concentration among teachers to examine whether hair cortisol can be a biomarker of chronic work stress.
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Genetic variants of the LIN28B gene predict severe radiation pneumonitis in patients with non-small cell lung cancer treated with definitive radiation therapy.
Eur. J. Cancer
PUBLISHED: 01-10-2014
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LIN28 is an RNA-binding protein that not only plays key roles in multiple cellular developmental processes and tumourigenesis, but also is involved in tissue inflammatory response. However, no published study has investigated associations between genetic variants in LIN28 and radiation-induced pneumonitis (RP) in patients with non-small cell lung cancer (NSCLC) treated with definitive radiation therapy.
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Identifying the interaction of maternal sensitivity and two serotonin-related gene polymorphisms on infant self-regulation.
Infant Behav Dev
PUBLISHED: 01-03-2014
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During infancy, orienting and gaze aversion serve as major self-regulatory mechanisms and play an important role in the development of deliberate self-regulation and control. The present study examined the interaction of intrinsic factors (MAOA-uVNTR and 5-HTTLPR gene polymorphisms) and extrinsic factors (maternal sensitivity) on early infant self-regulatory behavior. We assessed 5-HTTLPR (ss+sl versus ll) and MAOA-uVNTR (3 and 4 among boys, and 3/3, 3/4, and 4/4 among girls) polymorphisms, determined maternal sensitivity during mother-child free play, and coded infant self-regulatory behavior (i.e., orienting shifts in a temperament test) in 281 six-month-old infants. We found that infants who experienced a lower level of maternal sensitivity and had the short allele of 5-HTTLPR variants and the 3/3 MAOA-uVNTR polymorphism displayed lower self-regulation capacity than did those infants with a higher level of maternal sensitivity. This finding suggested a modulatory role of maternal sensitivity. Moreover, these findings are consistent with the genetic vulnerability hypothesis, which states that beneficial environmental factors serve as a buffer against harmful genetic predispositions during child development.
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Warming reduces tall fescue abundance but stimulates toxic alkaloid concentrations in transition zone pastures of the U.S.
Front Chem
PUBLISHED: 01-01-2014
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Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte also produces alkaloids toxic to insects (e.g., lolines) and mammals (ergots; which can cause "fescue toxicosis" in grazing animals). The negative animal health and economic consequences of fescue toxicosis make understanding the response of the tall fescue symbiosis to climate change critical for the region. We experimentally increased temperature (+3°C) and growing season precipitation (+30% of the long-term mean) from 2009-2013 in a mixed species pasture, that included a tall fescue population that was 40% endophyte-infected. Warming reduced the relative abundance of tall fescue within the plant community, and additional precipitation did not ameliorate this effect. Warming did not alter the incidence of endophyte infection within the tall fescue population; however, warming significantly increased concentrations of ergot alkaloids (by 30-40%) in fall-harvested endophyte-infected individuals. Warming alone did not affect loline alkaloid concentrations, but when combined with additional precipitation, levels increased in fall-harvested material. Although future warming may reduce the dominance of tall fescue in eastern U.S. pastures and have limited effect on the incidence of endophyte infection, persisting endophyte-infected tall fescue will have higher concentrations of toxic alkaloids which may exacerbate fescue toxicosis.
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Transfer of cadmium from soil to vegetable in the Pearl River Delta area, South China.
PLoS ONE
PUBLISHED: 01-01-2014
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The purpose of this study was to investigate the regional Cadmium (Cd) concentration levels in soils and in leaf vegetables across the Pearl River Delta (PRD) area; and reveal the transfer characteristics of Cadmium (Cd) from soils to leaf vegetable species on a regional scale. 170 paired vegetables and corresponding surface soil samples in the study area were collected for calculating the transfer factors of Cadmium (Cd) from soils to vegetables. This investigation revealed that in the study area Cd concentration in soils was lower (mean value 0.158 mg kg(-1)) compared with other countries or regions. The Cd-contaminated areas are mainly located in west areas of the Pearl River Delta. Cd concentrations in all vegetables were lower than the national standard of Safe vegetables (0.2 mg kg(-1)). 88% of vegetable samples met the standard of No-Polluted vegetables (0.05 mg kg(-1)). The Cd concentration in vegetables was mainly influenced by the interactions of total Cd concentration in soils, soil pH and vegetable species. The fit lines of soil-to-plant transfer factors and total Cd concentration in soils for various vegetable species were best described by the exponential equation (y = ax(b)), and these fit lines can be divided into two parts, including the sharply decrease part with a large error range, and the slowly decrease part with a low error range, according to the gradual increasing of total Cd concentrations in soils.
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Uncoupling of glomerular IgA deposition and disease progression in alymphoplasia mice with IgA nephropathy.
PLoS ONE
PUBLISHED: 01-01-2014
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Previous clinical and experimental studies have indicated that cells responsible for IgA nephropathy (IgAN), at least in part, are localized in bone marrow (BM). Indeed, we have demonstrated that murine IgAN can be experimentally reconstituted by bone marrow transplantation (BMT) from IgAN prone mice in not only normal mice, but also in alymphoplasia mice (aly/aly) independent of IgA+ cells homing to mucosa or secondary lymphoid tissues. The objective of the present study was to further assess whether secondary lymph nodes (LN) contribute to the progression of this disease. BM cells from the several lines of IgAN prone mice were transplanted into aly/aly and wild-type mice (B6). Although the transplanted aly/aly showed the same degree of mesangial IgA and IgG deposition and the same serum elevation levels of IgA and IgA-IgG immune-complexes (IC) as B6, even in extent, the progression of glomerular injury was observed only in B6. This uncoupling in aly/aly was associated with a lack of CD4+ T cells and macrophage infiltration, although phlogogenic capacity to nephritogenic IC of renal resident cells was identical between both recipients. It is suggested that secondary LN may be required for the full progression of IgAN after nephritogenic IgA and IgA/IgG IC deposition.
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Atg5 deficiency-mediated mitophagy aggravates cardiac inflammation and injury in response to angiotensin II.
Free Radic. Biol. Med.
PUBLISHED: 01-01-2014
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Hypertension induces end-organ damage through inflammation, and autophagy plays a crucial role in the regulation of cellular homeostasis. In the present study, we aimed to define the role of autophagy in the development of inflammation and cardiac injury induced by angiotensin II (Ang II).
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Hypermethylation of Sp1 binding site suppresses hypothalamic POMC in neonates and may contribute to metabolic disorders in adults: impact of maternal dietary CLA.
Diabetes
PUBLISHED: 12-30-2013
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Epigenetic regulation of neuropeptide genes associated with central appetite control plays an important part in the development of nutritional programming. While POMC is critical in appetite control, the molecular mechanism of methylation-related regulation of POMC remains unclear. Based on the report that the proximal Sp1 binding site in POMC promoter is crucial for the leptin-mediated activation of POMC, the methylation of this site was investigated here in both cultured cells and postnatal mice reared by the dams with dietary supplementation of CLA. The change of milk composition made the offspring undergo the increase of food intake, the suppression of POMC, the attenuation of Sp1-promoter interaction and the hypermethylation of CpG dinucleotides at -100 and -103 within Sp1 binding site of POMC promoter, which may be associated with the decrease of hypothalamic Sp1 and/or plasma S-adenosylhomocystein. In cultured cells the methylation of the -100 CpG dinucleotides of POMC promoter blocked both the formation of Sp1-promoter complex and the leptin-induced activation of POMC. In addition, a catch-up growth and adult metabolic changes like adult hyperglycemia and insulin resistance were observed in these postnatal pups, suggesting that this CLA-mediated hypermethylation may contribute, at least in part, to the metabolic disorders.
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Complete genome sequence of a novel pigeon torque teno virus in china.
Genome Announc
PUBLISHED: 12-21-2013
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Torque teno virus is a nonenveloped single-stranded DNA virus infecting humans and nonprimate species. We report the complete genome sequence of a pigeon torque teno virus isolated from pigeons in Jiangsu Province, China, in 2012. This genome sequence will be useful for viral diagnostics and disease control.
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Associations between single-nucleotide polymorphisms in the PI3K-PTEN-AKT-mTOR pathway and increased risk of brain metastasis in patients with non-small cell lung cancer.
Clin. Cancer Res.
PUBLISHED: 09-27-2013
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Non-small cell lung cancer (NSCLC) metastasizes fairly often to the brain, but identifying which patients will develop brain metastases is problematic. The phosphoinositide 3-kinase (PI3K)-AKT-mTOR signaling pathway is important in the control of cell growth, tumorigenesis, and cell invasion. We hypothesized that genotype variants in this pathway could predict brain metastasis in patients with NSCLC. Methods: We genotyped 16 single-nucleotide polymorphisms (SNP) in five core genes (PIK3CA, PTEN, AKT1, AKT2, and FRAP1) by using DNA from blood samples of 317 patients with NSCLC, and evaluated potential associations with the subsequent development of brain metastasis, the cumulative incidence of which was estimated with Kaplan-Meier analysis. Multivariate Cox regression analysis was used to analyze correlations between genotype variants and the occurrence of brain metastasis.
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Potential role of mannose-binding lectin in intrauterine transmission of hepatitis B virus.
Jpn. J. Infect. Dis.
PUBLISHED: 09-20-2013
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Intrauterine transmission of hepatitis B virus (HBV) is the main cause of the high prevalence of HBV in endemic areas; however, the mechanisms underlying intrauterine transmission of HBV remain unknown. To explore the role of mannose-binding lectin (MBL), a pattern recognition molecule of the innate immune system, in intrauterine transmission of HBV, we determined MBL levels using an enzyme-linked immunosorbent assay (ELISA) in cord serum of 7 intrauterine-infected neonates and 30 non-infected neonates born to HBV-positive mothers, and 30 control neonates born to HBV-negative mothers. We observed significant differences in cord serum MBL levels among the three groups (P < 0.001). Non-infected neonates had significantly higher MBL levels than controls (P < 0.001), and intrauterine-infected neonates had significantly lower serum MBL levels than non-infected neonates (P < 0.001). However, serum MBL levels were not significantly different between intrauterine-infected neonates and controls (P = 0.800). Our results indicate that maternal HBV infection induces an increase in fetal MBL levels and the absence of this increase is possibly associated with intrauterine transmission of HBV, suggesting that MBL plays a role in intrauterine transmission of HBV.
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Aerobic production of succinate from arabinose by metabolically engineered Corynebacterium glutamicum.
Bioresour. Technol.
PUBLISHED: 07-11-2013
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Arabinose is considered as an ideal feedstock for the microbial production of value-added chemicals due to its abundance in hemicellulosic wastes. In this study, the araBAD operon from Escherichia coli was introduced into succinate-producing Corynebacterium glutamicum, which enabled aerobic production of succinate using arabinose as sole carbon source. The engineered strain ZX1 (pXaraBAD, pEacsAgltA) produced 74.4mM succinate with a yield of 0.58mol (molarabinose)(-1), which represented 69.9% of the theoretically maximal yield. Moreover, this strain produced 110.2mM succinate using combined substrates of glucose and arabinose. To date, this is the highest succinate production under aerobic conditions in minimal medium.
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Improved succinate production in Corynebacterium glutamicum by engineering glyoxylate pathway and succinate export system.
Biotechnol. Lett.
PUBLISHED: 06-28-2013
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A dual route for anaerobic succinate production was engineered into Corynebacterium glutamicum. The glyoxylate pathway was reconstructed by overexpressing isocitrate lyase, malate synthase and citrate synthase. The engineered strain produced succinate with a yield of 1.34 mol (mol glucose)(-1). Further overexpression of succinate exporter, SucE, increased succinate yield to 1.43 mol (mol glucose)(-1). Metabolic flux analysis revealed that the glyoxylate pathway was further activated by engineering succinate export system. Using an anaerobic fed-batch fermentation process, the final strain produced 926 mM succinate (= 109 g l(-1)) with an overall volumetric productivity of 9.4 mM h(-1) and an average yield of 1.32 mol (mol glucose)(-1).
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Characteristics of novel hair-based biomarker for the activity assessment of 11?-hydroxysteroid dehydrogenase.
Clin. Chim. Acta
PUBLISHED: 06-24-2013
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The ratio of hair cortisol to cortisone (R(hcc)) would be a potential biomarker to assess long-term activity of 11?-hydroxysteroid dehydrogenase (11?-HSD). Hair cortisol concentration in human varied with positions of hair segments in hair shaft, head locations of hair sampling and treatment methods of hair samples. However, currently unknown is whether these factors influence the determination of R(hcc) value.
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A randomized, open-label study of sirolimus versus cyclosporine in primary de novo renal allograft recipients.
Transplantation
PUBLISHED: 05-22-2013
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Despite a decreased incidence of acute rejection and early renal allograft loss due to calcineurin inhibitors (CNIs) in transplant recipients, nephrotoxicity associated with long-term CNI use remains an important issue. This study evaluated whether a CNI-free regimen, including sirolimus, mycophenolate mofetil, corticosteroids, and anti-interleukin-2 receptor antibody induction, results in improved long-term renal function.
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Protein hypersaline adaptation: insight from amino acids with machine learning algorithms.
Protein J.
PUBLISHED: 04-18-2013
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Traditional bioinformatics methods performed systematic comparison between the halophilic proteins and their non-halophilic homologues, to investigate the features related to hypersaline adaptation. Therefore, proposing some quantitative models to explain the sequence-characteristic relationship of halophilic proteins might shed new light on haloadaptation and help to design new biocatalysts adapt to high salt concentration. Five machine learning algorithm, including three linear and two non-linear methods were used to discriminate halophilic and their non-halophilic counterparts and the prediction accuracy was encouraging. The best prediction reliability for halophilic proteins was achieved by artificial neural network and support vector machine and reached 80 %, for non-halophilic proteins, it was achieved by linear regression and reached 100 %. Besides, the linear models have captured some clues for protein halo-stability. Among them, lower frequency of Ser in halophilic protein has not been report before.
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Association of p53 and MDM2 polymorphisms with risk of human papillomavirus (HPV)-related esophageal squamous cell carcinoma (ESCC).
Cancer Epidemiol
PUBLISHED: 04-15-2013
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Though polymorphisms of the tumor suppressor gene p53 have been extensively investigated in numerous tumors, particularly tumors associated with human papillomavirus (HPV) infection. However, the results remain controversial. Our previous study showed that HPV serostatus is not an independent risk factor for esophageal squamous cell carcinoma (ESCC) in nonsmokers and nondrinkers. Given the roles of p53 and HPV E6 as well as MDM2 oncoproteins in p53 degradation, we validated the association of p53 and MDM2 polymorphisms with ESCC risk stratified by HPV16 sero-status.
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Support vector machine with a Pearson VII function kernel for discriminating halophilic and non-halophilic proteins.
Comput Biol Chem
PUBLISHED: 04-12-2013
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Understanding of proteins adaptive to hypersaline environment and identifying them is a challenging task and would help to design stable proteins. Here, we have systematically analyzed the normalized amino acid compositions of 2121 halophilic and 2400 non-halophilic proteins. The results showed that halophilic protein contained more Asp at the expense of Lys, Ile, Cys and Met, fewer small and hydrophobic residues, and showed a large excess of acidic over basic amino acids. Then, we introduce a support vector machine method to discriminate the halophilic and non-halophilic proteins, by using a novel Pearson VII universal function based kernel. In the three validation check methods, it achieved an overall accuracy of 97.7%, 91.7% and 86.9% and outperformed other machine learning algorithms. We also address the influence of protein size on prediction accuracy and found the worse performance for small size proteins might be some significant residues (Cys and Lys) were missing in the proteins.
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Characterization of the methanogen community in a household anaerobic digester fed with swine manure in China.
Appl. Microbiol. Biotechnol.
PUBLISHED: 04-04-2013
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Household anaerobic digesters have been installed across rural China for biogas production, but information on methanogen community structure in these small biogas units is sparsely available. By creating clone libraries for 16S rRNA and methyl coenzyme M reductase alpha subunit (mcrA) genes, we investigated the methanogenic consortia in a household biogas digester treating swine manure. Operational taxonomic units (OTUs) were defined by comparative sequence analysis, seven OTUs were identified in the 16S rRNA gene library, and ten OTUs were identified in the mcrA gene library. Both libraries were dominated by clones highly related to the type strain Methanocorpusculum labreanum Z, 64.0 % for 16S rRNA gene clones and 64.3 % for mcrA gene clones. Additionally, gas chromatography assays showed that formic acid was 84.54 % of the total volatile fatty acids and methane was 57.20 % of the biogas composition. Our results may help further isolation and characterization of methanogenic starter strains for industrial biogas production.
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Baicalin attenuates acute myocardial infarction of rats via mediating the mitogen-activated protein kinase pathway.
Biol. Pharm. Bull.
PUBLISHED: 03-30-2013
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Baicalin is a bioactive ingredient from the herb and has possessed various pharmacological actions. The present study was performed to evaluate the cardioprotective potential of baicalin against myocardial infarction and explore the potential mechanism. Baicalin was intraperitoneally injected into the rats by the doses of 50, 100 and 200 mg/kg, respectively, once a day for 7 d and, 30 min after the last administration, the left coronary artery was ligated. Infarct size was measured to analyze the myocardial damage. Myocardial specific enzymes, including creatine kinase (CK), the MB isoenzyme of creatine kinase (CK-MB), lactate dehydrogenase (LDH) and cardiac troponin T (cTnT) were determined with the colorimetric method. Evidence for myocardial apoptosis was detected by caspase-3 activity measurement and Western blot analysis. We also examined the protein levels of three major subgroups of mitogen-activated protein kinases (MAPKs), namely, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 by immuoblotting. Our results indicated that baicalin significantly reduced the infarct size and myocardial enzymes (CK, CK-MB, LDH and cTnT). Administration of baicalin also suppressed the activity and protein expression of caspase-3. Moreover, the protein level of phosphorylated ERK (p-ERK) was found to be evidently augmented while the phosphorylated JNK (p-JNK) and phosphorylated p38 (p-p38) were strikingly diminished in infarcted rats with baicalin treatment. These findings suggest that the baicalins cardioprotection associates with mediation of MAPK cascades in acute myocardial infarction of rats.
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Relating the variation of secondary structure of gelatin at fish oil-water interface to adsorption kinetics, dynamic interfacial tension and emulsion stability.
Food Chem
PUBLISHED: 03-21-2013
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The objectives of this study were to quantify the relationship between secondary structure of gelatin and its adsorption at the fish-oil/water interface and to quantify the implication of the adsorption on the dynamic interfacial tension (DST) and emulsion stability. The surface hydrophobicity of the gelatin solutions decreased when the pH increased from 4.0 to 6.0, while opposite tend was observed in the viscosity of the solution. The DST values decreased as the pH increased from 4.0 to 6.0, indicating that higher positive charges (measured trough zeta potential) in the gelatin solution tended to result in higher DST values. The adsorption kinetics of the gelatin solution was examined through the calculated diffusion coefficients (Deff). The addition of acid promoted the random coil and ?-turn structures at the expense of ?-helical structure. The addition of NaOH decreased the ?-turn and increased the ?-helix and random coil. The decrease in the random coil and triple helix structures in the gelatin solution resulted into increased Deff values. The highest diffusion coefficients, the highest emulsion stability and the lowest amount of random coil and triple helix structures were observed at pH=4.8. The lowest amount of random coil and triple helix structures in the interfacial protein layer correlated with the highest stability of the emulsion (highest ESI value). The lower amount of random coil and triple helix structures allowed higher coverage of the oil-water interface by relatively highly ordered secondary structure of gelatin.
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Effect of montmorillonite on morphology, glass transition and crystallinity of the xylitol-plasticized bionanocomposites.
Carbohydr Polym
PUBLISHED: 03-19-2013
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High amylose based nanocomposites plasticized by xylitol were prepared via twin-screw extrusion. The synergistic interaction in the xylitol-plasticized nanocomposite was studied via various characterization methods and the unique behavior of the xylitol-plasticized nanocomposite had been discussed. As revealed in the XRD and TEM results, good intercalated/exfoliated morphology had been achieved in all the nanocomposites. Furthermore, the expansion of nanoclay basal spacing was related to the xylitol/nanoclay ratio. DSC analysis clearly proved the unique crystallization process of xylitol-plasticized samples. Moreover, in the crystallization domain results, two domains sized at approximately 93.7 Å and 346 Å were found. This observation points to a two-level complex effect from two aggregate domains; one, the re-aggregation of certain number of silicate layers into domains which trap some of the amylose polymer chains, and two, the bulk drying process which combines smaller amylose crystalline domains within a larger amorphous high amylose matrix.
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Industrial sector-based volatile organic compound (VOC) source profiles measured in manufacturing facilities in the Pearl River Delta, China.
Sci. Total Environ.
PUBLISHED: 03-12-2013
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Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles.
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Study on dissolution mechanism of cortisol and cortisone from hair matrix with liquid chromatography-tandem mass spectrometry.
Clin. Chim. Acta
PUBLISHED: 02-27-2013
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Hair cortisol has been used as a biomarker of chronic stress. The detected contents of hair cortisol might depend on the incubation duration in solvents for no-milled hair samples with 3-layer structure. However, there was no research on the dissolution mechanism of hair analytes.
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Simultaneous determination of hair cortisol, cortisone and DHEAS with liquid chromatography-electrospray ionization-tandem mass spectrometry in negative mode.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-28-2013
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The present study aimed to develop a novel method for simultaneous assay of cortisol, cortisone and dehydroepiandrosterone sulfate (DHEAS) in human hair. The method was based on liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-MS/MS) in negative mode. Analytes were extracted from 20-mg hair incubated in 1ml of methanol for 5 days. 100?l non-SPE supernatant of the incubation solution was utilized in LC-MS/MS analysis. The liquid chromatography separation was performed on a reversed-phase C18 column with a mobile phase of 80:20 (v:v) methanol and deionized water containing 0.1% formic acid. The use of ESI in negative mode and the use of a small volume of the incubation solution significantly improved assay sensitivity. The linear range was 5-250pg/mg for cortisol and cortisone, and 5-500pg/mg for DHEAS. The limit of detection was 2pg/mg for the three analytes in hair. The coefficients of variation for intra-day and inter-day assay were less than 10%. The method was applied to determine the three analytes mentioned above of hair samples from 103 participants. The results indicated that there was no significant effect of age and education level on the hair cortisol, cortisone and DHEAS levels. The simple treatment procedure developed in the present study may facilitate simultaneous measurement of more steroids in hair.
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Synergistic Effect between Sphingosine-1-Phosphate and Chemotherapy Drugs against Human Brain-metastasized Breast Cancer MDA-MB-361 cells.
J Cancer
PUBLISHED: 01-25-2013
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Sphingosine-1-phosphate (S1P) is an important sphingolipid metabolite regulating key physiological and pathophysiological processes such as cell growth and survival and tumor angiogenesis. Significant research evidence links elevated cellular S1P concentration to cancer cell proliferation, migration and angiogenesis. Physiological levels of S1P are tightly regulated and maintained at the low nanomolar level. In cancer, S1P may exist well beyond the low nanomolar level. Recently, we reported that S1P selectively induces cell apoptosis of the breast cancer MCF7 cell line at concentrations higher than 1 µM and co-administration of 1 µM S1P significantly increased the cytotoxicity of chemotherapy drug docetaxel. In this study, we show that S1P caused minor increases in cell proliferation or apoptosis, in a concentration-dependent manner, yet co-administration of 10 µM S1P exhibited a significant synergistic effect with chemotherapy drugs docetaxel, doxorubicin and cyclophosphamide. S1P increased the cytotoxic potential of each drug by 2-fold, 3-fold, and 10-fold, respectively, against the breast cancer metastatic cell line MDA-MB-361. This synergism may suggest improved anticancer drug therapy by co-administration of exogenous S1P.
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Polymorphisms at the microRNA binding-site of the stem cell marker gene CD133 modify susceptibility to and survival of gastric cancer.
Mol. Carcinog.
PUBLISHED: 01-11-2013
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CD133 is one of the most common stem cell markers, and functional single nucleotide polymorphisms (SNPs) of CD133 may modulate its gene functions and thus cancer risk and patient survival. We hypothesized that potentially functional CD133 SNPs are associated with gastric cancer (GC) risk and survival. To test this hypothesis, we conducted a case-control study of 371 GC patients and 313 cancer-free controls frequency-matched by age, sex, and ethnicity. We genotyped four selected, potentially functional CD133 SNPs (rs2240688A>C, rs7686732C>G, rs10022537T>A, and rs3130C>T) and used logistic regression analysis for associations of these SNPs with GC risk and Cox hazards regression analysis for survival. We found that compared with the miRNA binding site rs2240688 AA genotype, AC?+?CC genotypes were associated with significantly increased GC risk (adjusted OR?=?1.52, 95% CI?=?1.09-2.13); for another miRNA binding site rs3130C>T SNP, the TT genotype was associated with significantly reduced GC risk (adjusted OR?=?0.68, 95% CI?=?0.48-0.97), compared with CC?+?CT genotypes. In all patients, the risk rs3130 TT variant genotype was significantly associated with overall survival (OS) (adjusted Ptrend ?=?0.016 and 0.007 under additive and recessive models, respectively). These findings suggest that these two CD133 miRNA binding site variants, rs2240688 and rs3130, may be potential biomarkers for genetic susceptibility to GC and possible predictors for survival in GC patients but require further validation by larger studies. © 2013 Wiley Periodicals, Inc.
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Quantitative analysis of steroid hormones in human hair using a column-switching LC-APCI-MS/MS assay.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-10-2013
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The analysis of steroid hormones in hair is increasingly used in the field of stress-related research to obtain a retrospective index of integrated long-term hormone secretion. Here, most laboratories have so far relied on immunochemical assays originally developed for salivary analyses. Although these assays are fast and easy to perform, they have a reduced reliability and specificity due to cross-reactivity with other substances and are limited to the detection of one hormone at a time. Here, we report the development of a LC-MS/MS-based method for simultaneous identification of endogenous concentrations of seven steroid hormones (cortisol, cortisone, testosterone, progesterone, corticosterone, dehydroepiandrosterone (DHEA) and androstenedione) in human hair. Hair samples were washed with isopropanol and steroid hormones were extracted from 10mg whole, nonpulverized hair by methanol incubation. A column switching strategy for on-line solid phase extraction (SPE) was applied, followed by analyte detection on an AB Sciex API 5000 QTrap mass spectrometer. Results indicated linearity of the method for all steroids over ranges of 0.09-90pg/mg (0.9-900pg/mg for DHEA) with correlation coefficients ranging between 0.9995 and 0.9999. Intra- and inter-assay coefficients of variation were between 3.7 and 9.1%. The limits of quantification (LOQ) were below (or equal to) 0.1pg/mg for all steroids, except of DHEA for which the LOQ was 0.9pg/mg. An analysis of 30 natural hair samples (15 men/15 women) using this method confirmed that all steroid hormones could be quantified at endogenous levels in each individual. In addition, the use of whole hair samples and on-line SPE resulted in a significant reduction in sample throughput times, increasing the applicability of this method for research questions where a larger number of samples needs to be processed.
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Impact of Three Oral Antidiabetic Drugs on Markers of ?-Cell Function in Patients with Type 2 Diabetes: A Meta-Analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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The effect of metformin, pioglitazone and sitagliptin on ?-cell function in the treatment of type 2 diabetes is controversial. Therefore, we performed a systematic review and meta-analysis to obtain a better understanding in the ?-cell effects of metformin, pioglitazone and sitagliptin.
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Screening E3 substrates using a live phage display library.
PLoS ONE
PUBLISHED: 01-01-2013
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Ubiquitin ligases (E3s) determine specificity of ubiquitination by recognizing target substrates. However, most of their substrates are unknown. Most known substrates have been identified using distinct approaches in different laboratories. We developed a high-throughput strategy using a live phage display library as E3 substrates in in vitro screening. His-ubiquitinated phage, enriched with Ni-beads, could effectively infect E. coli for amplification. Sixteen natural potential substrates and many unnatural potential substrates of E3 MDM2 were identified through 4 independent screenings. Some substrates were identified in different independent experiments. Additionally, 10 of 12 selected candidates were ubiquitinated by MDM2 in vitro, and 3 novel substrates, DDX42, TP53RK and RPL36a were confirmed ex vivo. The whole strategy is rather simple and efficient. Non-degradation substrates can be discovered. This strategy can be extended to any E3s as long as the E3 does not ubiquitinate the empty phage.
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Patterns of linkage disequilibrium of LRRK2 across different races: implications for genetic association studies.
PLoS ONE
PUBLISHED: 01-01-2013
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Genome Wide Association Studies (GWASs) have identified trait-associated polymorphisms via a hypothesis-free approach. However, it is challenging when attempting to reproduce GWAS findings in different populations as it fundamentally relies on the similar patterns of linkage disequilibrium (LD) between the unknown causal variants and the genotyped single nucleotide polymorphisms (SNPs). To address this potential limitation, we examined the regional LD pattern of leucine-rich repeat kinase 2 (LRRK2) gene, which is responsible for both autosomal dominant and sporadic Parkinsons disease (PD), in Caucasians (CEU), Japanese (JPT) and Chinese (CHB) from HapMap and Chinese (CHS), Malays (MAS) and Indians (INS) from the Singapore Genome Variation Project (SGVP) utilizing the traditional heatmaps and targeted analysis of LRRK2 gene via Monte Carlo simulation through varLD scores of these ethnic groups. Both heatmaps and targeted analysis showed that LD pattern of JPT was different from that of INS (P=0.0001); while LD pattern of CEU was different from that in Asian except for INS (all P=0.0001). Our study suggests that there is a higher chance to detect associations between PD and those trait-associated SNPs of LRRK2 gene found in Caucasian studies in INS, while those found in Japanese studies are likely to be better replicated among CHB.
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Identification of serum monocyte chemoattractant protein-1 and prolactin as potential tumor markers in hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2013
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Early diagnosis of hepatocellullar carcinoma (HCC) remains a challenge. The current practice of serum alpha-fetoprotein (AFP) measurement is inadequate. Here we utilized a proteomic approach to identify novel serum biomarkers for distinguishing HCC patients from non-cancer controls. We profiled the serum proteins in a group of 58 resectable HCC patients and 11 non-HCC chronic hepatitis B (HBV) carrier samples from the Singapore General Hospital (SGH) using the RayBio® L-Series 507 Antibody Array and found 113 serum markers that were significantly modulated between HCC and control groups. Selected potential biomarkers from this list were quantified using a multiplex sandwich enzyme-linked immunosorbent assay (ELISA) array in an expanded SGH cohort (126 resectable HCC patients and 115 non-HCC chronic HBV carriers (NC group)), confirming that serum prolactin and monocyte chemoattractant protein-1 (MCP-1) were significantly upregulated in HCC patients. This finding of serum MCP-1 elevation in HCC patients was validated in a separate cohort of serum samples from the Mochtar Riady Institute for Nanotechnology, Indonesia (98 resectable HCC, 101 chronic hepatitis B patients and 100 asymptomatic HBV/HCV carriers) by sandwich ELISA. MCP-1 and prolactin levels were found to correlate with AFP, while MCP-1 also correlated with disease stage. Subsequent receiver operating characteristic (ROC) analysis of AFP, prolactin and MCP-1 in the SGH cohort and comparing their area under the ROC curve (AUC) indicated that neither prolactin nor MCP-1 on their own performed better than AFP. However, the combination of AFP+MCP-1 (AUC, 0.974) had significantly superior discriminative ability than AFP alone (AUC, 0.942; p<0.001). In conclusion, prolactin and MCP-1 are overexpressed in HCC and are conveniently quantifiable in patients sera by ELISA. MCP-1 appears to be a promising complementary biomarker for HCC diagnosis and this MCP-1+AFP model should be further evaluated as potential biomarker on a larger scale in patients at-risk of HCC.
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Engineering of acetate recycling and citrate synthase to improve aerobic succinate production in Corynebacterium glutamicum.
PLoS ONE
PUBLISHED: 01-01-2013
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Corynebacterium glutamicum lacking the succinate dehydrogenase complex can produce succinate aerobically with acetate representing the major byproduct. Efforts to increase succinate production involved deletion of acetate formation pathways and overexpression of anaplerotic pathways, but acetate formation could not be completely eliminated. To address this issue, we constructed a pathway for recycling wasted carbon in succinate-producing C. glutamicum. The acetyl-CoA synthetase from Bacillus subtilis was heterologously introduced into C. glutamicum for the first time. The engineered strain ZX1 (pEacsA) did not secrete acetate and produced succinate with a yield of 0.50 mol (mol glucose)(-1). Moreover, in order to drive more carbon towards succinate biosynthesis, the native citrate synthase encoded by gltA was overexpressed, leading to strain ZX1 (pEacsAgltA), which showed a 22% increase in succinate yield and a 62% decrease in pyruvate yield compared to strain ZX1 (pEacsA). In fed-batch cultivations, strain ZX1 (pEacsAgltA) produced 241 mM succinate with an average volumetric productivity of 3.55 mM h(-1) and an average yield of 0.63 mol (mol glucose) (-1), making it a promising platform for the aerobic production of succinate at large scale.
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Predicting clinical behaviour of breast phyllodes tumours: a nomogram based on histological criteria and surgical margins.
J. Clin. Pathol.
PUBLISHED: 11-02-2011
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To define a predictive model for clinical behaviour of breast phyllodes tumours (PT) using histological parameters and surgical margin status.
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Modification of pineapple peel fibre with succinic anhydride for Cu2+, Cd2+ and Pb2+ removal from aqueous solutions.
Environ Technol
PUBLISHED: 09-02-2011
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Research on chemical modification of pineapple peel fibre with succinic anhydride was carried out to create a novel adsorbent for Cu2+, Cd2+ and Pb2+ removal from aqueous solution. After pretreatment with iso-propyl alcohol and NaOH, pineapple peel fibre was modified via reaction with succinic anhydride for introduction of carboxylic functional groups. The modified pineapple peel fibre was characterized with Fourier transform infrared (FTIR) spectroscopy and evaluated for its adsorptive ability for Cu2+, Cd2+ and Pb2+ from synthetic metal solutions. The FTIR analysis proved the introduction of carboxylic functional groups in the backbone of the modified pineapple peel fibre. The modified pineapple peel fibre showed higher adsorptive capacity for Cu2+, Cd2+ and Pb2+ compared with raw pineapple peel and pineapple peel fibre pretreated with iso-propyl alcohol. The adsorption of Cu2+, Cd2+ and Pb2+ on the modified pineapple peel fibre depended on solution pH value, adsorption time and initial metal concentration. The maximum adsorption capacities of the modified fibre were observed at pH 5.4 for Cu2+ (27.68 +/- 0.83 mg g(-1) or 0.44 mmol g(-1)), at pH 7.5 for Cd2+ (34.18 +/- 1.02 mg g(-1) or 0.30 mmol g(-1)) and at pH 5.6 for Pb2+ (70.29 +/- 2.11 mg g(-1) or 0.34 mmol g(-1)) respectively. The adsorption followed the pseudo-second-order kinetics model and the experimental data coincided well with the Langmuir model.
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Analysis of prognostic factors of comprehensive geriatric assessment and development of a clinical scoring system in elderly Asian patients with cancer.
J. Clin. Oncol.
PUBLISHED: 08-22-2011
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To determine the impact of each comprehensive geriatric assessment (CGA) domain on overall survival (OS) and develop a prognostic scoring system for elderly patients with cancer.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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